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v6.13.7
    1// SPDX-License-Identifier: GPL-2.0-or-later
    2/*
    3 *      NET3    Protocol independent device support routines.
 
 
 
 
 
    4 *
    5 *	Derived from the non IP parts of dev.c 1.0.19
    6 *              Authors:	Ross Biro
    7 *				Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
    8 *				Mark Evans, <evansmp@uhura.aston.ac.uk>
    9 *
   10 *	Additional Authors:
   11 *		Florian la Roche <rzsfl@rz.uni-sb.de>
   12 *		Alan Cox <gw4pts@gw4pts.ampr.org>
   13 *		David Hinds <dahinds@users.sourceforge.net>
   14 *		Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
   15 *		Adam Sulmicki <adam@cfar.umd.edu>
   16 *              Pekka Riikonen <priikone@poesidon.pspt.fi>
   17 *
   18 *	Changes:
   19 *              D.J. Barrow     :       Fixed bug where dev->refcnt gets set
   20 *                                      to 2 if register_netdev gets called
   21 *                                      before net_dev_init & also removed a
   22 *                                      few lines of code in the process.
   23 *		Alan Cox	:	device private ioctl copies fields back.
   24 *		Alan Cox	:	Transmit queue code does relevant
   25 *					stunts to keep the queue safe.
   26 *		Alan Cox	:	Fixed double lock.
   27 *		Alan Cox	:	Fixed promisc NULL pointer trap
   28 *		????????	:	Support the full private ioctl range
   29 *		Alan Cox	:	Moved ioctl permission check into
   30 *					drivers
   31 *		Tim Kordas	:	SIOCADDMULTI/SIOCDELMULTI
   32 *		Alan Cox	:	100 backlog just doesn't cut it when
   33 *					you start doing multicast video 8)
   34 *		Alan Cox	:	Rewrote net_bh and list manager.
   35 *              Alan Cox        :       Fix ETH_P_ALL echoback lengths.
   36 *		Alan Cox	:	Took out transmit every packet pass
   37 *					Saved a few bytes in the ioctl handler
   38 *		Alan Cox	:	Network driver sets packet type before
   39 *					calling netif_rx. Saves a function
   40 *					call a packet.
   41 *		Alan Cox	:	Hashed net_bh()
   42 *		Richard Kooijman:	Timestamp fixes.
   43 *		Alan Cox	:	Wrong field in SIOCGIFDSTADDR
   44 *		Alan Cox	:	Device lock protection.
   45 *              Alan Cox        :       Fixed nasty side effect of device close
   46 *					changes.
   47 *		Rudi Cilibrasi	:	Pass the right thing to
   48 *					set_mac_address()
   49 *		Dave Miller	:	32bit quantity for the device lock to
   50 *					make it work out on a Sparc.
   51 *		Bjorn Ekwall	:	Added KERNELD hack.
   52 *		Alan Cox	:	Cleaned up the backlog initialise.
   53 *		Craig Metz	:	SIOCGIFCONF fix if space for under
   54 *					1 device.
   55 *	    Thomas Bogendoerfer :	Return ENODEV for dev_open, if there
   56 *					is no device open function.
   57 *		Andi Kleen	:	Fix error reporting for SIOCGIFCONF
   58 *	    Michael Chastain	:	Fix signed/unsigned for SIOCGIFCONF
   59 *		Cyrus Durgin	:	Cleaned for KMOD
   60 *		Adam Sulmicki   :	Bug Fix : Network Device Unload
   61 *					A network device unload needs to purge
   62 *					the backlog queue.
   63 *	Paul Rusty Russell	:	SIOCSIFNAME
   64 *              Pekka Riikonen  :	Netdev boot-time settings code
   65 *              Andrew Morton   :       Make unregister_netdevice wait
   66 *                                      indefinitely on dev->refcnt
   67 *              J Hadi Salim    :       - Backlog queue sampling
   68 *				        - netif_rx() feedback
   69 */
   70
   71#include <linux/uaccess.h>
   72#include <linux/bitmap.h>
 
   73#include <linux/capability.h>
   74#include <linux/cpu.h>
   75#include <linux/types.h>
   76#include <linux/kernel.h>
   77#include <linux/hash.h>
   78#include <linux/slab.h>
   79#include <linux/sched.h>
   80#include <linux/sched/isolation.h>
   81#include <linux/sched/mm.h>
   82#include <linux/smpboot.h>
   83#include <linux/mutex.h>
   84#include <linux/rwsem.h>
   85#include <linux/string.h>
   86#include <linux/mm.h>
   87#include <linux/socket.h>
   88#include <linux/sockios.h>
   89#include <linux/errno.h>
   90#include <linux/interrupt.h>
   91#include <linux/if_ether.h>
   92#include <linux/netdevice.h>
   93#include <linux/etherdevice.h>
   94#include <linux/ethtool.h>
 
   95#include <linux/skbuff.h>
   96#include <linux/kthread.h>
   97#include <linux/bpf.h>
   98#include <linux/bpf_trace.h>
   99#include <net/net_namespace.h>
  100#include <net/sock.h>
  101#include <net/busy_poll.h>
  102#include <linux/rtnetlink.h>
 
 
  103#include <linux/stat.h>
  104#include <net/dsa.h>
  105#include <net/dst.h>
  106#include <net/dst_metadata.h>
  107#include <net/gro.h>
  108#include <net/pkt_sched.h>
  109#include <net/pkt_cls.h>
  110#include <net/checksum.h>
  111#include <net/xfrm.h>
  112#include <net/tcx.h>
  113#include <linux/highmem.h>
  114#include <linux/init.h>
 
  115#include <linux/module.h>
  116#include <linux/netpoll.h>
  117#include <linux/rcupdate.h>
  118#include <linux/delay.h>
 
  119#include <net/iw_handler.h>
  120#include <asm/current.h>
  121#include <linux/audit.h>
  122#include <linux/dmaengine.h>
  123#include <linux/err.h>
  124#include <linux/ctype.h>
  125#include <linux/if_arp.h>
  126#include <linux/if_vlan.h>
  127#include <linux/ip.h>
  128#include <net/ip.h>
  129#include <net/mpls.h>
  130#include <linux/ipv6.h>
  131#include <linux/in.h>
  132#include <linux/jhash.h>
  133#include <linux/random.h>
  134#include <trace/events/napi.h>
  135#include <trace/events/net.h>
  136#include <trace/events/skb.h>
  137#include <trace/events/qdisc.h>
  138#include <trace/events/xdp.h>
  139#include <linux/inetdevice.h>
  140#include <linux/cpu_rmap.h>
  141#include <linux/static_key.h>
  142#include <linux/hashtable.h>
  143#include <linux/vmalloc.h>
  144#include <linux/if_macvlan.h>
  145#include <linux/errqueue.h>
  146#include <linux/hrtimer.h>
  147#include <linux/netfilter_netdev.h>
  148#include <linux/crash_dump.h>
  149#include <linux/sctp.h>
  150#include <net/udp_tunnel.h>
  151#include <linux/net_namespace.h>
  152#include <linux/indirect_call_wrapper.h>
  153#include <net/devlink.h>
  154#include <linux/pm_runtime.h>
  155#include <linux/prandom.h>
  156#include <linux/once_lite.h>
  157#include <net/netdev_rx_queue.h>
  158#include <net/page_pool/types.h>
  159#include <net/page_pool/helpers.h>
  160#include <net/rps.h>
  161#include <linux/phy_link_topology.h>
  162
  163#include "dev.h"
  164#include "devmem.h"
  165#include "net-sysfs.h"
  166
  167static DEFINE_SPINLOCK(ptype_lock);
  168struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
  169
  170static int netif_rx_internal(struct sk_buff *skb);
  171static int call_netdevice_notifiers_extack(unsigned long val,
  172					   struct net_device *dev,
  173					   struct netlink_ext_ack *extack);
  174
  175static DEFINE_MUTEX(ifalias_mutex);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  176
  177/* protects napi_hash addition/deletion and napi_gen_id */
  178static DEFINE_SPINLOCK(napi_hash_lock);
  179
  180static unsigned int napi_gen_id = NR_CPUS;
  181static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8);
 
  182
  183static DECLARE_RWSEM(devnet_rename_sem);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  184
  185static inline void dev_base_seq_inc(struct net *net)
  186{
  187	unsigned int val = net->dev_base_seq + 1;
  188
  189	WRITE_ONCE(net->dev_base_seq, val ?: 1);
  190}
  191
  192static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
  193{
  194	unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ));
  195
  196	return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
  197}
  198
  199static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
  200{
  201	return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
  202}
  203
  204#ifndef CONFIG_PREEMPT_RT
  205
  206static DEFINE_STATIC_KEY_FALSE(use_backlog_threads_key);
  207
  208static int __init setup_backlog_napi_threads(char *arg)
  209{
  210	static_branch_enable(&use_backlog_threads_key);
  211	return 0;
  212}
  213early_param("thread_backlog_napi", setup_backlog_napi_threads);
  214
  215static bool use_backlog_threads(void)
  216{
  217	return static_branch_unlikely(&use_backlog_threads_key);
  218}
  219
  220#else
  221
  222static bool use_backlog_threads(void)
  223{
  224	return true;
  225}
  226
  227#endif
  228
  229static inline void backlog_lock_irq_save(struct softnet_data *sd,
  230					 unsigned long *flags)
  231{
  232	if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads())
  233		spin_lock_irqsave(&sd->input_pkt_queue.lock, *flags);
  234	else
  235		local_irq_save(*flags);
  236}
  237
  238static inline void backlog_lock_irq_disable(struct softnet_data *sd)
  239{
  240	if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads())
  241		spin_lock_irq(&sd->input_pkt_queue.lock);
  242	else
  243		local_irq_disable();
  244}
  245
  246static inline void backlog_unlock_irq_restore(struct softnet_data *sd,
  247					      unsigned long *flags)
  248{
  249	if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads())
  250		spin_unlock_irqrestore(&sd->input_pkt_queue.lock, *flags);
  251	else
  252		local_irq_restore(*flags);
  253}
  254
  255static inline void backlog_unlock_irq_enable(struct softnet_data *sd)
  256{
  257	if (IS_ENABLED(CONFIG_RPS) || use_backlog_threads())
  258		spin_unlock_irq(&sd->input_pkt_queue.lock);
  259	else
  260		local_irq_enable();
  261}
  262
  263static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev,
  264						       const char *name)
  265{
  266	struct netdev_name_node *name_node;
  267
  268	name_node = kmalloc(sizeof(*name_node), GFP_KERNEL);
  269	if (!name_node)
  270		return NULL;
  271	INIT_HLIST_NODE(&name_node->hlist);
  272	name_node->dev = dev;
  273	name_node->name = name;
  274	return name_node;
  275}
  276
  277static struct netdev_name_node *
  278netdev_name_node_head_alloc(struct net_device *dev)
  279{
  280	struct netdev_name_node *name_node;
  281
  282	name_node = netdev_name_node_alloc(dev, dev->name);
  283	if (!name_node)
  284		return NULL;
  285	INIT_LIST_HEAD(&name_node->list);
  286	return name_node;
  287}
  288
  289static void netdev_name_node_free(struct netdev_name_node *name_node)
  290{
  291	kfree(name_node);
  292}
  293
  294static void netdev_name_node_add(struct net *net,
  295				 struct netdev_name_node *name_node)
  296{
  297	hlist_add_head_rcu(&name_node->hlist,
  298			   dev_name_hash(net, name_node->name));
  299}
  300
  301static void netdev_name_node_del(struct netdev_name_node *name_node)
  302{
  303	hlist_del_rcu(&name_node->hlist);
  304}
  305
  306static struct netdev_name_node *netdev_name_node_lookup(struct net *net,
  307							const char *name)
  308{
  309	struct hlist_head *head = dev_name_hash(net, name);
  310	struct netdev_name_node *name_node;
  311
  312	hlist_for_each_entry(name_node, head, hlist)
  313		if (!strcmp(name_node->name, name))
  314			return name_node;
  315	return NULL;
  316}
  317
  318static struct netdev_name_node *netdev_name_node_lookup_rcu(struct net *net,
  319							    const char *name)
  320{
  321	struct hlist_head *head = dev_name_hash(net, name);
  322	struct netdev_name_node *name_node;
  323
  324	hlist_for_each_entry_rcu(name_node, head, hlist)
  325		if (!strcmp(name_node->name, name))
  326			return name_node;
  327	return NULL;
  328}
  329
  330bool netdev_name_in_use(struct net *net, const char *name)
  331{
  332	return netdev_name_node_lookup(net, name);
  333}
  334EXPORT_SYMBOL(netdev_name_in_use);
  335
  336int netdev_name_node_alt_create(struct net_device *dev, const char *name)
  337{
  338	struct netdev_name_node *name_node;
  339	struct net *net = dev_net(dev);
  340
  341	name_node = netdev_name_node_lookup(net, name);
  342	if (name_node)
  343		return -EEXIST;
  344	name_node = netdev_name_node_alloc(dev, name);
  345	if (!name_node)
  346		return -ENOMEM;
  347	netdev_name_node_add(net, name_node);
  348	/* The node that holds dev->name acts as a head of per-device list. */
  349	list_add_tail_rcu(&name_node->list, &dev->name_node->list);
  350
  351	return 0;
  352}
  353
  354static void netdev_name_node_alt_free(struct rcu_head *head)
  355{
  356	struct netdev_name_node *name_node =
  357		container_of(head, struct netdev_name_node, rcu);
  358
  359	kfree(name_node->name);
  360	netdev_name_node_free(name_node);
  361}
  362
  363static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node)
  364{
  365	netdev_name_node_del(name_node);
  366	list_del(&name_node->list);
  367	call_rcu(&name_node->rcu, netdev_name_node_alt_free);
  368}
  369
  370int netdev_name_node_alt_destroy(struct net_device *dev, const char *name)
  371{
  372	struct netdev_name_node *name_node;
  373	struct net *net = dev_net(dev);
  374
  375	name_node = netdev_name_node_lookup(net, name);
  376	if (!name_node)
  377		return -ENOENT;
  378	/* lookup might have found our primary name or a name belonging
  379	 * to another device.
  380	 */
  381	if (name_node == dev->name_node || name_node->dev != dev)
  382		return -EINVAL;
  383
  384	__netdev_name_node_alt_destroy(name_node);
  385	return 0;
  386}
  387
  388static void netdev_name_node_alt_flush(struct net_device *dev)
  389{
  390	struct netdev_name_node *name_node, *tmp;
  391
  392	list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list) {
  393		list_del(&name_node->list);
  394		netdev_name_node_alt_free(&name_node->rcu);
  395	}
  396}
  397
  398/* Device list insertion */
  399static void list_netdevice(struct net_device *dev)
  400{
  401	struct netdev_name_node *name_node;
  402	struct net *net = dev_net(dev);
  403
  404	ASSERT_RTNL();
  405
 
  406	list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
  407	netdev_name_node_add(net, dev->name_node);
  408	hlist_add_head_rcu(&dev->index_hlist,
  409			   dev_index_hash(net, dev->ifindex));
  410
  411	netdev_for_each_altname(dev, name_node)
  412		netdev_name_node_add(net, name_node);
  413
  414	/* We reserved the ifindex, this can't fail */
  415	WARN_ON(xa_store(&net->dev_by_index, dev->ifindex, dev, GFP_KERNEL));
  416
  417	dev_base_seq_inc(net);
 
 
  418}
  419
  420/* Device list removal
  421 * caller must respect a RCU grace period before freeing/reusing dev
  422 */
  423static void unlist_netdevice(struct net_device *dev)
  424{
  425	struct netdev_name_node *name_node;
  426	struct net *net = dev_net(dev);
  427
  428	ASSERT_RTNL();
  429
  430	xa_erase(&net->dev_by_index, dev->ifindex);
  431
  432	netdev_for_each_altname(dev, name_node)
  433		netdev_name_node_del(name_node);
  434
  435	/* Unlink dev from the device chain */
 
  436	list_del_rcu(&dev->dev_list);
  437	netdev_name_node_del(dev->name_node);
  438	hlist_del_rcu(&dev->index_hlist);
 
  439
  440	dev_base_seq_inc(dev_net(dev));
  441}
  442
  443/*
  444 *	Our notifier list
  445 */
  446
  447static RAW_NOTIFIER_HEAD(netdev_chain);
  448
  449/*
  450 *	Device drivers call our routines to queue packets here. We empty the
  451 *	queue in the local softnet handler.
  452 */
  453
  454DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data) = {
  455	.process_queue_bh_lock = INIT_LOCAL_LOCK(process_queue_bh_lock),
  456};
  457EXPORT_PER_CPU_SYMBOL(softnet_data);
  458
  459/* Page_pool has a lockless array/stack to alloc/recycle pages.
  460 * PP consumers must pay attention to run APIs in the appropriate context
  461 * (e.g. NAPI context).
  462 */
  463static DEFINE_PER_CPU(struct page_pool *, system_page_pool);
  464
  465#ifdef CONFIG_LOCKDEP
  466/*
  467 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
  468 * according to dev->type
  469 */
  470static const unsigned short netdev_lock_type[] = {
  471	 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
  472	 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
  473	 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
  474	 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
  475	 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
  476	 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
  477	 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
  478	 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
  479	 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
  480	 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
  481	 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
  482	 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
  483	 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
  484	 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
  485	 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
  486
  487static const char *const netdev_lock_name[] = {
  488	"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
  489	"_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
  490	"_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
  491	"_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
  492	"_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
  493	"_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
  494	"_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
  495	"_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
  496	"_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
  497	"_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
  498	"_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
  499	"_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
  500	"_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
  501	"_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
  502	"_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
 
 
  503
  504static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
  505static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
  506
  507static inline unsigned short netdev_lock_pos(unsigned short dev_type)
  508{
  509	int i;
  510
  511	for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
  512		if (netdev_lock_type[i] == dev_type)
  513			return i;
  514	/* the last key is used by default */
  515	return ARRAY_SIZE(netdev_lock_type) - 1;
  516}
  517
  518static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
  519						 unsigned short dev_type)
  520{
  521	int i;
  522
  523	i = netdev_lock_pos(dev_type);
  524	lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
  525				   netdev_lock_name[i]);
  526}
  527
  528static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
  529{
  530	int i;
  531
  532	i = netdev_lock_pos(dev->type);
  533	lockdep_set_class_and_name(&dev->addr_list_lock,
  534				   &netdev_addr_lock_key[i],
  535				   netdev_lock_name[i]);
  536}
  537#else
  538static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
  539						 unsigned short dev_type)
  540{
  541}
  542
  543static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
  544{
  545}
  546#endif
  547
  548/*******************************************************************************
  549 *
  550 *		Protocol management and registration routines
  551 *
  552 *******************************************************************************/
  553
 
 
 
  554
  555/*
  556 *	Add a protocol ID to the list. Now that the input handler is
  557 *	smarter we can dispense with all the messy stuff that used to be
  558 *	here.
  559 *
  560 *	BEWARE!!! Protocol handlers, mangling input packets,
  561 *	MUST BE last in hash buckets and checking protocol handlers
  562 *	MUST start from promiscuous ptype_all chain in net_bh.
  563 *	It is true now, do not change it.
  564 *	Explanation follows: if protocol handler, mangling packet, will
  565 *	be the first on list, it is not able to sense, that packet
  566 *	is cloned and should be copied-on-write, so that it will
  567 *	change it and subsequent readers will get broken packet.
  568 *							--ANK (980803)
  569 */
  570
  571static inline struct list_head *ptype_head(const struct packet_type *pt)
  572{
  573	if (pt->type == htons(ETH_P_ALL))
  574		return pt->dev ? &pt->dev->ptype_all : &net_hotdata.ptype_all;
  575	else
  576		return pt->dev ? &pt->dev->ptype_specific :
  577				 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
  578}
  579
  580/**
  581 *	dev_add_pack - add packet handler
  582 *	@pt: packet type declaration
  583 *
  584 *	Add a protocol handler to the networking stack. The passed &packet_type
  585 *	is linked into kernel lists and may not be freed until it has been
  586 *	removed from the kernel lists.
  587 *
  588 *	This call does not sleep therefore it can not
  589 *	guarantee all CPU's that are in middle of receiving packets
  590 *	will see the new packet type (until the next received packet).
  591 */
  592
  593void dev_add_pack(struct packet_type *pt)
  594{
  595	struct list_head *head = ptype_head(pt);
  596
  597	spin_lock(&ptype_lock);
  598	list_add_rcu(&pt->list, head);
  599	spin_unlock(&ptype_lock);
  600}
  601EXPORT_SYMBOL(dev_add_pack);
  602
  603/**
  604 *	__dev_remove_pack	 - remove packet handler
  605 *	@pt: packet type declaration
  606 *
  607 *	Remove a protocol handler that was previously added to the kernel
  608 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
  609 *	from the kernel lists and can be freed or reused once this function
  610 *	returns.
  611 *
  612 *      The packet type might still be in use by receivers
  613 *	and must not be freed until after all the CPU's have gone
  614 *	through a quiescent state.
  615 */
  616void __dev_remove_pack(struct packet_type *pt)
  617{
  618	struct list_head *head = ptype_head(pt);
  619	struct packet_type *pt1;
  620
  621	spin_lock(&ptype_lock);
  622
  623	list_for_each_entry(pt1, head, list) {
  624		if (pt == pt1) {
  625			list_del_rcu(&pt->list);
  626			goto out;
  627		}
  628	}
  629
  630	pr_warn("dev_remove_pack: %p not found\n", pt);
  631out:
  632	spin_unlock(&ptype_lock);
  633}
  634EXPORT_SYMBOL(__dev_remove_pack);
  635
  636/**
  637 *	dev_remove_pack	 - remove packet handler
  638 *	@pt: packet type declaration
  639 *
  640 *	Remove a protocol handler that was previously added to the kernel
  641 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
  642 *	from the kernel lists and can be freed or reused once this function
  643 *	returns.
  644 *
  645 *	This call sleeps to guarantee that no CPU is looking at the packet
  646 *	type after return.
  647 */
  648void dev_remove_pack(struct packet_type *pt)
  649{
  650	__dev_remove_pack(pt);
  651
  652	synchronize_net();
  653}
  654EXPORT_SYMBOL(dev_remove_pack);
  655
 
  656
  657/*******************************************************************************
  658 *
  659 *			    Device Interface Subroutines
  660 *
  661 *******************************************************************************/
 
  662
  663/**
  664 *	dev_get_iflink	- get 'iflink' value of a interface
  665 *	@dev: targeted interface
 
  666 *
  667 *	Indicates the ifindex the interface is linked to.
  668 *	Physical interfaces have the same 'ifindex' and 'iflink' values.
 
  669 */
  670
  671int dev_get_iflink(const struct net_device *dev)
  672{
  673	if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink)
  674		return dev->netdev_ops->ndo_get_iflink(dev);
 
 
 
 
 
 
 
 
 
 
  675
  676	return READ_ONCE(dev->ifindex);
  677}
  678EXPORT_SYMBOL(dev_get_iflink);
  679
  680/**
  681 *	dev_fill_metadata_dst - Retrieve tunnel egress information.
  682 *	@dev: targeted interface
  683 *	@skb: The packet.
  684 *
  685 *	For better visibility of tunnel traffic OVS needs to retrieve
  686 *	egress tunnel information for a packet. Following API allows
  687 *	user to get this info.
 
  688 */
  689int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
  690{
  691	struct ip_tunnel_info *info;
  692
  693	if (!dev->netdev_ops  || !dev->netdev_ops->ndo_fill_metadata_dst)
  694		return -EINVAL;
  695
  696	info = skb_tunnel_info_unclone(skb);
  697	if (!info)
  698		return -ENOMEM;
  699	if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX)))
  700		return -EINVAL;
  701
  702	return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb);
 
 
 
 
 
 
 
 
 
 
  703}
  704EXPORT_SYMBOL_GPL(dev_fill_metadata_dst);
  705
  706static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack)
  707{
  708	int k = stack->num_paths++;
  709
  710	if (WARN_ON_ONCE(k >= NET_DEVICE_PATH_STACK_MAX))
  711		return NULL;
  712
  713	return &stack->path[k];
  714}
  715
  716int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr,
  717			  struct net_device_path_stack *stack)
 
 
 
 
 
 
 
 
 
  718{
  719	const struct net_device *last_dev;
  720	struct net_device_path_ctx ctx = {
  721		.dev	= dev,
  722	};
  723	struct net_device_path *path;
  724	int ret = 0;
  725
  726	memcpy(ctx.daddr, daddr, sizeof(ctx.daddr));
  727	stack->num_paths = 0;
  728	while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) {
  729		last_dev = ctx.dev;
  730		path = dev_fwd_path(stack);
  731		if (!path)
  732			return -1;
  733
  734		memset(path, 0, sizeof(struct net_device_path));
  735		ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path);
  736		if (ret < 0)
  737			return -1;
  738
  739		if (WARN_ON_ONCE(last_dev == ctx.dev))
  740			return -1;
  741	}
  742
  743	if (!ctx.dev)
  744		return ret;
  745
  746	path = dev_fwd_path(stack);
  747	if (!path)
  748		return -1;
  749	path->type = DEV_PATH_ETHERNET;
  750	path->dev = ctx.dev;
 
  751
  752	return ret;
 
 
 
  753}
  754EXPORT_SYMBOL_GPL(dev_fill_forward_path);
  755
  756/* must be called under rcu_read_lock(), as we dont take a reference */
  757static struct napi_struct *napi_by_id(unsigned int napi_id)
 
 
  758{
  759	unsigned int hash = napi_id % HASH_SIZE(napi_hash);
  760	struct napi_struct *napi;
 
 
 
 
  761
  762	hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
  763		if (napi->napi_id == napi_id)
  764			return napi;
 
 
 
 
 
 
 
  765
  766	return NULL;
 
  767}
  768
  769/* must be called under rcu_read_lock(), as we dont take a reference */
  770struct napi_struct *netdev_napi_by_id(struct net *net, unsigned int napi_id)
  771{
  772	struct napi_struct *napi;
  773
  774	napi = napi_by_id(napi_id);
  775	if (!napi)
  776		return NULL;
  777
  778	if (WARN_ON_ONCE(!napi->dev))
  779		return NULL;
  780	if (!net_eq(net, dev_net(napi->dev)))
  781		return NULL;
  782
  783	return napi;
  784}
  785
  786/**
  787 *	__dev_get_by_name	- find a device by its name
  788 *	@net: the applicable net namespace
  789 *	@name: name to find
  790 *
  791 *	Find an interface by name. Must be called under RTNL semaphore.
  792 *	If the name is found a pointer to the device is returned.
  793 *	If the name is not found then %NULL is returned. The
  794 *	reference counters are not incremented so the caller must be
  795 *	careful with locks.
  796 */
  797
  798struct net_device *__dev_get_by_name(struct net *net, const char *name)
  799{
  800	struct netdev_name_node *node_name;
 
 
 
 
 
 
  801
  802	node_name = netdev_name_node_lookup(net, name);
  803	return node_name ? node_name->dev : NULL;
  804}
  805EXPORT_SYMBOL(__dev_get_by_name);
  806
  807/**
  808 * dev_get_by_name_rcu	- find a device by its name
  809 * @net: the applicable net namespace
  810 * @name: name to find
  811 *
  812 * Find an interface by name.
  813 * If the name is found a pointer to the device is returned.
  814 * If the name is not found then %NULL is returned.
  815 * The reference counters are not incremented so the caller must be
  816 * careful with locks. The caller must hold RCU lock.
  817 */
  818
  819struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
  820{
  821	struct netdev_name_node *node_name;
  822
  823	node_name = netdev_name_node_lookup_rcu(net, name);
  824	return node_name ? node_name->dev : NULL;
  825}
  826EXPORT_SYMBOL(dev_get_by_name_rcu);
  827
  828/* Deprecated for new users, call netdev_get_by_name() instead */
  829struct net_device *dev_get_by_name(struct net *net, const char *name)
  830{
  831	struct net_device *dev;
 
  832
  833	rcu_read_lock();
  834	dev = dev_get_by_name_rcu(net, name);
  835	dev_hold(dev);
  836	rcu_read_unlock();
  837	return dev;
  838}
  839EXPORT_SYMBOL(dev_get_by_name);
  840
  841/**
  842 *	netdev_get_by_name() - find a device by its name
  843 *	@net: the applicable net namespace
  844 *	@name: name to find
  845 *	@tracker: tracking object for the acquired reference
  846 *	@gfp: allocation flags for the tracker
  847 *
  848 *	Find an interface by name. This can be called from any
  849 *	context and does its own locking. The returned handle has
  850 *	the usage count incremented and the caller must use netdev_put() to
  851 *	release it when it is no longer needed. %NULL is returned if no
  852 *	matching device is found.
  853 */
  854struct net_device *netdev_get_by_name(struct net *net, const char *name,
  855				      netdevice_tracker *tracker, gfp_t gfp)
  856{
  857	struct net_device *dev;
  858
  859	dev = dev_get_by_name(net, name);
 
  860	if (dev)
  861		netdev_tracker_alloc(dev, tracker, gfp);
 
  862	return dev;
  863}
  864EXPORT_SYMBOL(netdev_get_by_name);
  865
  866/**
  867 *	__dev_get_by_index - find a device by its ifindex
  868 *	@net: the applicable net namespace
  869 *	@ifindex: index of device
  870 *
  871 *	Search for an interface by index. Returns %NULL if the device
  872 *	is not found or a pointer to the device. The device has not
  873 *	had its reference counter increased so the caller must be careful
  874 *	about locking. The caller must hold the RTNL semaphore.
 
  875 */
  876
  877struct net_device *__dev_get_by_index(struct net *net, int ifindex)
  878{
 
  879	struct net_device *dev;
  880	struct hlist_head *head = dev_index_hash(net, ifindex);
  881
  882	hlist_for_each_entry(dev, head, index_hlist)
  883		if (dev->ifindex == ifindex)
  884			return dev;
  885
  886	return NULL;
  887}
  888EXPORT_SYMBOL(__dev_get_by_index);
  889
  890/**
  891 *	dev_get_by_index_rcu - find a device by its ifindex
  892 *	@net: the applicable net namespace
  893 *	@ifindex: index of device
  894 *
  895 *	Search for an interface by index. Returns %NULL if the device
  896 *	is not found or a pointer to the device. The device has not
  897 *	had its reference counter increased so the caller must be careful
  898 *	about locking. The caller must hold RCU lock.
  899 */
  900
  901struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
  902{
 
  903	struct net_device *dev;
  904	struct hlist_head *head = dev_index_hash(net, ifindex);
  905
  906	hlist_for_each_entry_rcu(dev, head, index_hlist)
  907		if (dev->ifindex == ifindex)
  908			return dev;
  909
  910	return NULL;
  911}
  912EXPORT_SYMBOL(dev_get_by_index_rcu);
  913
  914/* Deprecated for new users, call netdev_get_by_index() instead */
  915struct net_device *dev_get_by_index(struct net *net, int ifindex)
  916{
  917	struct net_device *dev;
  918
  919	rcu_read_lock();
  920	dev = dev_get_by_index_rcu(net, ifindex);
  921	dev_hold(dev);
  922	rcu_read_unlock();
  923	return dev;
  924}
  925EXPORT_SYMBOL(dev_get_by_index);
  926
  927/**
  928 *	netdev_get_by_index() - find a device by its ifindex
  929 *	@net: the applicable net namespace
  930 *	@ifindex: index of device
  931 *	@tracker: tracking object for the acquired reference
  932 *	@gfp: allocation flags for the tracker
  933 *
  934 *	Search for an interface by index. Returns NULL if the device
  935 *	is not found or a pointer to the device. The device returned has
  936 *	had a reference added and the pointer is safe until the user calls
  937 *	netdev_put() to indicate they have finished with it.
  938 */
  939struct net_device *netdev_get_by_index(struct net *net, int ifindex,
  940				       netdevice_tracker *tracker, gfp_t gfp)
  941{
  942	struct net_device *dev;
  943
  944	dev = dev_get_by_index(net, ifindex);
  945	if (dev)
  946		netdev_tracker_alloc(dev, tracker, gfp);
  947	return dev;
  948}
  949EXPORT_SYMBOL(netdev_get_by_index);
  950
  951/**
  952 *	dev_get_by_napi_id - find a device by napi_id
  953 *	@napi_id: ID of the NAPI struct
  954 *
  955 *	Search for an interface by NAPI ID. Returns %NULL if the device
  956 *	is not found or a pointer to the device. The device has not had
  957 *	its reference counter increased so the caller must be careful
  958 *	about locking. The caller must hold RCU lock.
  959 */
  960
  961struct net_device *dev_get_by_napi_id(unsigned int napi_id)
  962{
  963	struct napi_struct *napi;
  964
  965	WARN_ON_ONCE(!rcu_read_lock_held());
  966
  967	if (napi_id < MIN_NAPI_ID)
  968		return NULL;
  969
  970	napi = napi_by_id(napi_id);
  971
  972	return napi ? napi->dev : NULL;
  973}
  974EXPORT_SYMBOL(dev_get_by_napi_id);
  975
  976static DEFINE_SEQLOCK(netdev_rename_lock);
  977
  978void netdev_copy_name(struct net_device *dev, char *name)
  979{
  980	unsigned int seq;
  981
  982	do {
  983		seq = read_seqbegin(&netdev_rename_lock);
  984		strscpy(name, dev->name, IFNAMSIZ);
  985	} while (read_seqretry(&netdev_rename_lock, seq));
  986}
  987
  988/**
  989 *	netdev_get_name - get a netdevice name, knowing its ifindex.
  990 *	@net: network namespace
  991 *	@name: a pointer to the buffer where the name will be stored.
  992 *	@ifindex: the ifindex of the interface to get the name from.
  993 */
  994int netdev_get_name(struct net *net, char *name, int ifindex)
  995{
  996	struct net_device *dev;
  997	int ret;
  998
  999	rcu_read_lock();
 1000
 1001	dev = dev_get_by_index_rcu(net, ifindex);
 1002	if (!dev) {
 1003		ret = -ENODEV;
 1004		goto out;
 1005	}
 1006
 1007	netdev_copy_name(dev, name);
 1008
 1009	ret = 0;
 1010out:
 1011	rcu_read_unlock();
 1012	return ret;
 1013}
 1014
 1015static bool dev_addr_cmp(struct net_device *dev, unsigned short type,
 1016			 const char *ha)
 1017{
 1018	return dev->type == type && !memcmp(dev->dev_addr, ha, dev->addr_len);
 1019}
 
 1020
 1021/**
 1022 *	dev_getbyhwaddr_rcu - find a device by its hardware address
 1023 *	@net: the applicable net namespace
 1024 *	@type: media type of device
 1025 *	@ha: hardware address
 1026 *
 1027 *	Search for an interface by MAC address. Returns NULL if the device
 1028 *	is not found or a pointer to the device.
 1029 *	The caller must hold RCU.
 1030 *	The returned device has not had its ref count increased
 1031 *	and the caller must therefore be careful about locking
 1032 *
 1033 */
 1034
 1035struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
 1036				       const char *ha)
 1037{
 1038	struct net_device *dev;
 1039
 1040	for_each_netdev_rcu(net, dev)
 1041		if (dev_addr_cmp(dev, type, ha))
 
 1042			return dev;
 1043
 1044	return NULL;
 1045}
 1046EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
 1047
 1048/**
 1049 * dev_getbyhwaddr() - find a device by its hardware address
 1050 * @net: the applicable net namespace
 1051 * @type: media type of device
 1052 * @ha: hardware address
 1053 *
 1054 * Similar to dev_getbyhwaddr_rcu(), but the owner needs to hold
 1055 * rtnl_lock.
 1056 *
 1057 * Context: rtnl_lock() must be held.
 1058 * Return: pointer to the net_device, or NULL if not found
 1059 */
 1060struct net_device *dev_getbyhwaddr(struct net *net, unsigned short type,
 1061				   const char *ha)
 1062{
 1063	struct net_device *dev;
 1064
 1065	ASSERT_RTNL();
 1066	for_each_netdev(net, dev)
 1067		if (dev_addr_cmp(dev, type, ha))
 1068			return dev;
 1069
 1070	return NULL;
 1071}
 1072EXPORT_SYMBOL(dev_getbyhwaddr);
 1073
 1074struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
 1075{
 1076	struct net_device *dev, *ret = NULL;
 1077
 1078	rcu_read_lock();
 1079	for_each_netdev_rcu(net, dev)
 1080		if (dev->type == type) {
 1081			dev_hold(dev);
 1082			ret = dev;
 1083			break;
 1084		}
 1085	rcu_read_unlock();
 1086	return ret;
 1087}
 1088EXPORT_SYMBOL(dev_getfirstbyhwtype);
 1089
 1090/**
 1091 *	__dev_get_by_flags - find any device with given flags
 1092 *	@net: the applicable net namespace
 1093 *	@if_flags: IFF_* values
 1094 *	@mask: bitmask of bits in if_flags to check
 1095 *
 1096 *	Search for any interface with the given flags. Returns NULL if a device
 1097 *	is not found or a pointer to the device. Must be called inside
 1098 *	rtnl_lock(), and result refcount is unchanged.
 1099 */
 1100
 1101struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags,
 1102				      unsigned short mask)
 1103{
 1104	struct net_device *dev, *ret;
 1105
 1106	ASSERT_RTNL();
 1107
 1108	ret = NULL;
 1109	for_each_netdev(net, dev) {
 1110		if (((dev->flags ^ if_flags) & mask) == 0) {
 1111			ret = dev;
 1112			break;
 1113		}
 1114	}
 1115	return ret;
 1116}
 1117EXPORT_SYMBOL(__dev_get_by_flags);
 1118
 1119/**
 1120 *	dev_valid_name - check if name is okay for network device
 1121 *	@name: name string
 1122 *
 1123 *	Network device names need to be valid file names to
 1124 *	allow sysfs to work.  We also disallow any kind of
 1125 *	whitespace.
 1126 */
 1127bool dev_valid_name(const char *name)
 1128{
 1129	if (*name == '\0')
 1130		return false;
 1131	if (strnlen(name, IFNAMSIZ) == IFNAMSIZ)
 1132		return false;
 1133	if (!strcmp(name, ".") || !strcmp(name, ".."))
 1134		return false;
 1135
 1136	while (*name) {
 1137		if (*name == '/' || *name == ':' || isspace(*name))
 1138			return false;
 1139		name++;
 1140	}
 1141	return true;
 1142}
 1143EXPORT_SYMBOL(dev_valid_name);
 1144
 1145/**
 1146 *	__dev_alloc_name - allocate a name for a device
 1147 *	@net: network namespace to allocate the device name in
 1148 *	@name: name format string
 1149 *	@res: result name string
 1150 *
 1151 *	Passed a format string - eg "lt%d" it will try and find a suitable
 1152 *	id. It scans list of devices to build up a free map, then chooses
 1153 *	the first empty slot. The caller must hold the dev_base or rtnl lock
 1154 *	while allocating the name and adding the device in order to avoid
 1155 *	duplicates.
 1156 *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
 1157 *	Returns the number of the unit assigned or a negative errno code.
 1158 */
 1159
 1160static int __dev_alloc_name(struct net *net, const char *name, char *res)
 1161{
 1162	int i = 0;
 1163	const char *p;
 1164	const int max_netdevices = 8*PAGE_SIZE;
 1165	unsigned long *inuse;
 1166	struct net_device *d;
 1167	char buf[IFNAMSIZ];
 1168
 1169	/* Verify the string as this thing may have come from the user.
 1170	 * There must be one "%d" and no other "%" characters.
 1171	 */
 1172	p = strchr(name, '%');
 1173	if (!p || p[1] != 'd' || strchr(p + 2, '%'))
 1174		return -EINVAL;
 1175
 1176	/* Use one page as a bit array of possible slots */
 1177	inuse = bitmap_zalloc(max_netdevices, GFP_ATOMIC);
 1178	if (!inuse)
 1179		return -ENOMEM;
 
 
 
 
 
 1180
 1181	for_each_netdev(net, d) {
 1182		struct netdev_name_node *name_node;
 
 
 1183
 1184		netdev_for_each_altname(d, name_node) {
 1185			if (!sscanf(name_node->name, name, &i))
 1186				continue;
 1187			if (i < 0 || i >= max_netdevices)
 1188				continue;
 1189
 1190			/* avoid cases where sscanf is not exact inverse of printf */
 1191			snprintf(buf, IFNAMSIZ, name, i);
 1192			if (!strncmp(buf, name_node->name, IFNAMSIZ))
 1193				__set_bit(i, inuse);
 1194		}
 1195		if (!sscanf(d->name, name, &i))
 1196			continue;
 1197		if (i < 0 || i >= max_netdevices)
 1198			continue;
 1199
 1200		/* avoid cases where sscanf is not exact inverse of printf */
 1201		snprintf(buf, IFNAMSIZ, name, i);
 1202		if (!strncmp(buf, d->name, IFNAMSIZ))
 1203			__set_bit(i, inuse);
 1204	}
 1205
 1206	i = find_first_zero_bit(inuse, max_netdevices);
 1207	bitmap_free(inuse);
 1208	if (i == max_netdevices)
 1209		return -ENFILE;
 1210
 1211	/* 'res' and 'name' could overlap, use 'buf' as an intermediate buffer */
 1212	strscpy(buf, name, IFNAMSIZ);
 1213	snprintf(res, IFNAMSIZ, buf, i);
 1214	return i;
 1215}
 1216
 1217/* Returns negative errno or allocated unit id (see __dev_alloc_name()) */
 1218static int dev_prep_valid_name(struct net *net, struct net_device *dev,
 1219			       const char *want_name, char *out_name,
 1220			       int dup_errno)
 1221{
 1222	if (!dev_valid_name(want_name))
 1223		return -EINVAL;
 1224
 1225	if (strchr(want_name, '%'))
 1226		return __dev_alloc_name(net, want_name, out_name);
 1227
 1228	if (netdev_name_in_use(net, want_name))
 1229		return -dup_errno;
 1230	if (out_name != want_name)
 1231		strscpy(out_name, want_name, IFNAMSIZ);
 1232	return 0;
 1233}
 1234
 1235/**
 1236 *	dev_alloc_name - allocate a name for a device
 1237 *	@dev: device
 1238 *	@name: name format string
 1239 *
 1240 *	Passed a format string - eg "lt%d" it will try and find a suitable
 1241 *	id. It scans list of devices to build up a free map, then chooses
 1242 *	the first empty slot. The caller must hold the dev_base or rtnl lock
 1243 *	while allocating the name and adding the device in order to avoid
 1244 *	duplicates.
 1245 *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
 1246 *	Returns the number of the unit assigned or a negative errno code.
 1247 */
 1248
 1249int dev_alloc_name(struct net_device *dev, const char *name)
 1250{
 1251	return dev_prep_valid_name(dev_net(dev), dev, name, dev->name, ENFILE);
 
 
 
 
 
 
 
 
 
 1252}
 1253EXPORT_SYMBOL(dev_alloc_name);
 1254
 1255static int dev_get_valid_name(struct net *net, struct net_device *dev,
 1256			      const char *name)
 1257{
 1258	int ret;
 
 
 
 1259
 1260	ret = dev_prep_valid_name(net, dev, name, dev->name, EEXIST);
 1261	return ret < 0 ? ret : 0;
 
 
 
 
 
 
 
 
 
 1262}
 1263
 1264/**
 1265 *	dev_change_name - change name of a device
 1266 *	@dev: device
 1267 *	@newname: name (or format string) must be at least IFNAMSIZ
 1268 *
 1269 *	Change name of a device, can pass format strings "eth%d".
 1270 *	for wildcarding.
 1271 */
 1272int dev_change_name(struct net_device *dev, const char *newname)
 1273{
 1274	unsigned char old_assign_type;
 1275	char oldname[IFNAMSIZ];
 1276	int err = 0;
 1277	int ret;
 1278	struct net *net;
 1279
 1280	ASSERT_RTNL();
 1281	BUG_ON(!dev_net(dev));
 1282
 1283	net = dev_net(dev);
 
 
 1284
 1285	down_write(&devnet_rename_sem);
 1286
 1287	if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
 1288		up_write(&devnet_rename_sem);
 1289		return 0;
 1290	}
 1291
 1292	memcpy(oldname, dev->name, IFNAMSIZ);
 1293
 1294	write_seqlock_bh(&netdev_rename_lock);
 1295	err = dev_get_valid_name(net, dev, newname);
 1296	write_sequnlock_bh(&netdev_rename_lock);
 1297
 1298	if (err < 0) {
 1299		up_write(&devnet_rename_sem);
 1300		return err;
 1301	}
 1302
 1303	if (oldname[0] && !strchr(oldname, '%'))
 1304		netdev_info(dev, "renamed from %s%s\n", oldname,
 1305			    dev->flags & IFF_UP ? " (while UP)" : "");
 1306
 1307	old_assign_type = dev->name_assign_type;
 1308	WRITE_ONCE(dev->name_assign_type, NET_NAME_RENAMED);
 1309
 1310rollback:
 1311	ret = device_rename(&dev->dev, dev->name);
 1312	if (ret) {
 1313		write_seqlock_bh(&netdev_rename_lock);
 1314		memcpy(dev->name, oldname, IFNAMSIZ);
 1315		write_sequnlock_bh(&netdev_rename_lock);
 1316		WRITE_ONCE(dev->name_assign_type, old_assign_type);
 1317		up_write(&devnet_rename_sem);
 1318		return ret;
 1319	}
 1320
 1321	up_write(&devnet_rename_sem);
 1322
 1323	netdev_adjacent_rename_links(dev, oldname);
 1324
 1325	netdev_name_node_del(dev->name_node);
 1326
 1327	synchronize_net();
 1328
 1329	netdev_name_node_add(net, dev->name_node);
 1330
 1331	ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
 1332	ret = notifier_to_errno(ret);
 1333
 1334	if (ret) {
 1335		/* err >= 0 after dev_alloc_name() or stores the first errno */
 1336		if (err >= 0) {
 1337			err = ret;
 1338			down_write(&devnet_rename_sem);
 1339			write_seqlock_bh(&netdev_rename_lock);
 1340			memcpy(dev->name, oldname, IFNAMSIZ);
 1341			write_sequnlock_bh(&netdev_rename_lock);
 1342			memcpy(oldname, newname, IFNAMSIZ);
 1343			WRITE_ONCE(dev->name_assign_type, old_assign_type);
 1344			old_assign_type = NET_NAME_RENAMED;
 1345			goto rollback;
 1346		} else {
 1347			netdev_err(dev, "name change rollback failed: %d\n",
 1348				   ret);
 
 1349		}
 1350	}
 1351
 1352	return err;
 1353}
 1354
 1355/**
 1356 *	dev_set_alias - change ifalias of a device
 1357 *	@dev: device
 1358 *	@alias: name up to IFALIASZ
 1359 *	@len: limit of bytes to copy from info
 1360 *
 1361 *	Set ifalias for a device,
 1362 */
 1363int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
 1364{
 1365	struct dev_ifalias *new_alias = NULL;
 1366
 1367	if (len >= IFALIASZ)
 1368		return -EINVAL;
 1369
 1370	if (len) {
 1371		new_alias = kmalloc(sizeof(*new_alias) + len + 1, GFP_KERNEL);
 1372		if (!new_alias)
 1373			return -ENOMEM;
 1374
 1375		memcpy(new_alias->ifalias, alias, len);
 1376		new_alias->ifalias[len] = 0;
 1377	}
 1378
 1379	mutex_lock(&ifalias_mutex);
 1380	new_alias = rcu_replace_pointer(dev->ifalias, new_alias,
 1381					mutex_is_locked(&ifalias_mutex));
 1382	mutex_unlock(&ifalias_mutex);
 1383
 1384	if (new_alias)
 1385		kfree_rcu(new_alias, rcuhead);
 1386
 
 1387	return len;
 1388}
 1389EXPORT_SYMBOL(dev_set_alias);
 1390
 1391/**
 1392 *	dev_get_alias - get ifalias of a device
 1393 *	@dev: device
 1394 *	@name: buffer to store name of ifalias
 1395 *	@len: size of buffer
 1396 *
 1397 *	get ifalias for a device.  Caller must make sure dev cannot go
 1398 *	away,  e.g. rcu read lock or own a reference count to device.
 1399 */
 1400int dev_get_alias(const struct net_device *dev, char *name, size_t len)
 1401{
 1402	const struct dev_ifalias *alias;
 1403	int ret = 0;
 1404
 1405	rcu_read_lock();
 1406	alias = rcu_dereference(dev->ifalias);
 1407	if (alias)
 1408		ret = snprintf(name, len, "%s", alias->ifalias);
 1409	rcu_read_unlock();
 1410
 1411	return ret;
 1412}
 1413
 1414/**
 1415 *	netdev_features_change - device changes features
 1416 *	@dev: device to cause notification
 1417 *
 1418 *	Called to indicate a device has changed features.
 1419 */
 1420void netdev_features_change(struct net_device *dev)
 1421{
 1422	call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
 1423}
 1424EXPORT_SYMBOL(netdev_features_change);
 1425
 1426/**
 1427 *	netdev_state_change - device changes state
 1428 *	@dev: device to cause notification
 1429 *
 1430 *	Called to indicate a device has changed state. This function calls
 1431 *	the notifier chains for netdev_chain and sends a NEWLINK message
 1432 *	to the routing socket.
 1433 */
 1434void netdev_state_change(struct net_device *dev)
 1435{
 1436	if (dev->flags & IFF_UP) {
 1437		struct netdev_notifier_change_info change_info = {
 1438			.info.dev = dev,
 1439		};
 1440
 1441		call_netdevice_notifiers_info(NETDEV_CHANGE,
 1442					      &change_info.info);
 1443		rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL, 0, NULL);
 1444	}
 1445}
 1446EXPORT_SYMBOL(netdev_state_change);
 1447
 1448/**
 1449 * __netdev_notify_peers - notify network peers about existence of @dev,
 1450 * to be called when rtnl lock is already held.
 1451 * @dev: network device
 1452 *
 1453 * Generate traffic such that interested network peers are aware of
 1454 * @dev, such as by generating a gratuitous ARP. This may be used when
 1455 * a device wants to inform the rest of the network about some sort of
 1456 * reconfiguration such as a failover event or virtual machine
 1457 * migration.
 1458 */
 1459void __netdev_notify_peers(struct net_device *dev)
 1460{
 1461	ASSERT_RTNL();
 1462	call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
 1463	call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev);
 1464}
 1465EXPORT_SYMBOL(__netdev_notify_peers);
 1466
 1467/**
 1468 * netdev_notify_peers - notify network peers about existence of @dev
 1469 * @dev: network device
 
 1470 *
 1471 * Generate traffic such that interested network peers are aware of
 1472 * @dev, such as by generating a gratuitous ARP. This may be used when
 1473 * a device wants to inform the rest of the network about some sort of
 1474 * reconfiguration such as a failover event or virtual machine
 1475 * migration.
 1476 */
 1477void netdev_notify_peers(struct net_device *dev)
 1478{
 1479	rtnl_lock();
 1480	__netdev_notify_peers(dev);
 1481	rtnl_unlock();
 1482}
 1483EXPORT_SYMBOL(netdev_notify_peers);
 1484
 1485static int napi_threaded_poll(void *data);
 1486
 1487static int napi_kthread_create(struct napi_struct *n)
 1488{
 1489	int err = 0;
 
 1490
 1491	/* Create and wake up the kthread once to put it in
 1492	 * TASK_INTERRUPTIBLE mode to avoid the blocked task
 1493	 * warning and work with loadavg.
 1494	 */
 1495	n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d",
 1496				n->dev->name, n->napi_id);
 1497	if (IS_ERR(n->thread)) {
 1498		err = PTR_ERR(n->thread);
 1499		pr_err("kthread_run failed with err %d\n", err);
 1500		n->thread = NULL;
 1501	}
 1502
 1503	return err;
 
 
 
 
 
 
 
 
 1504}
 
 1505
 1506static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack)
 1507{
 1508	const struct net_device_ops *ops = dev->netdev_ops;
 1509	int ret;
 1510
 1511	ASSERT_RTNL();
 1512	dev_addr_check(dev);
 1513
 1514	if (!netif_device_present(dev)) {
 1515		/* may be detached because parent is runtime-suspended */
 1516		if (dev->dev.parent)
 1517			pm_runtime_resume(dev->dev.parent);
 1518		if (!netif_device_present(dev))
 1519			return -ENODEV;
 1520	}
 1521
 1522	/* Block netpoll from trying to do any rx path servicing.
 1523	 * If we don't do this there is a chance ndo_poll_controller
 1524	 * or ndo_poll may be running while we open the device
 1525	 */
 1526	netpoll_poll_disable(dev);
 1527
 1528	ret = call_netdevice_notifiers_extack(NETDEV_PRE_UP, dev, extack);
 1529	ret = notifier_to_errno(ret);
 1530	if (ret)
 1531		return ret;
 1532
 1533	set_bit(__LINK_STATE_START, &dev->state);
 1534
 1535	if (ops->ndo_validate_addr)
 1536		ret = ops->ndo_validate_addr(dev);
 1537
 1538	if (!ret && ops->ndo_open)
 1539		ret = ops->ndo_open(dev);
 1540
 1541	netpoll_poll_enable(dev);
 1542
 1543	if (ret)
 1544		clear_bit(__LINK_STATE_START, &dev->state);
 1545	else {
 1546		dev->flags |= IFF_UP;
 
 1547		dev_set_rx_mode(dev);
 1548		dev_activate(dev);
 1549		add_device_randomness(dev->dev_addr, dev->addr_len);
 1550	}
 1551
 1552	return ret;
 1553}
 1554
 1555/**
 1556 *	dev_open	- prepare an interface for use.
 1557 *	@dev: device to open
 1558 *	@extack: netlink extended ack
 1559 *
 1560 *	Takes a device from down to up state. The device's private open
 1561 *	function is invoked and then the multicast lists are loaded. Finally
 1562 *	the device is moved into the up state and a %NETDEV_UP message is
 1563 *	sent to the netdev notifier chain.
 1564 *
 1565 *	Calling this function on an active interface is a nop. On a failure
 1566 *	a negative errno code is returned.
 1567 */
 1568int dev_open(struct net_device *dev, struct netlink_ext_ack *extack)
 1569{
 1570	int ret;
 1571
 1572	if (dev->flags & IFF_UP)
 1573		return 0;
 1574
 1575	ret = __dev_open(dev, extack);
 1576	if (ret < 0)
 1577		return ret;
 1578
 1579	rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL);
 1580	call_netdevice_notifiers(NETDEV_UP, dev);
 1581
 1582	return ret;
 1583}
 1584EXPORT_SYMBOL(dev_open);
 1585
 1586static void __dev_close_many(struct list_head *head)
 1587{
 1588	struct net_device *dev;
 1589
 1590	ASSERT_RTNL();
 1591	might_sleep();
 1592
 1593	list_for_each_entry(dev, head, close_list) {
 1594		/* Temporarily disable netpoll until the interface is down */
 1595		netpoll_poll_disable(dev);
 1596
 1597		call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
 1598
 1599		clear_bit(__LINK_STATE_START, &dev->state);
 1600
 1601		/* Synchronize to scheduled poll. We cannot touch poll list, it
 1602		 * can be even on different cpu. So just clear netif_running().
 1603		 *
 1604		 * dev->stop() will invoke napi_disable() on all of it's
 1605		 * napi_struct instances on this device.
 1606		 */
 1607		smp_mb__after_atomic(); /* Commit netif_running(). */
 1608	}
 1609
 1610	dev_deactivate_many(head);
 1611
 1612	list_for_each_entry(dev, head, close_list) {
 1613		const struct net_device_ops *ops = dev->netdev_ops;
 1614
 1615		/*
 1616		 *	Call the device specific close. This cannot fail.
 1617		 *	Only if device is UP
 1618		 *
 1619		 *	We allow it to be called even after a DETACH hot-plug
 1620		 *	event.
 1621		 */
 1622		if (ops->ndo_stop)
 1623			ops->ndo_stop(dev);
 1624
 1625		dev->flags &= ~IFF_UP;
 1626		netpoll_poll_enable(dev);
 1627	}
 
 
 1628}
 1629
 1630static void __dev_close(struct net_device *dev)
 1631{
 
 1632	LIST_HEAD(single);
 1633
 1634	list_add(&dev->close_list, &single);
 1635	__dev_close_many(&single);
 1636	list_del(&single);
 
 1637}
 1638
 1639void dev_close_many(struct list_head *head, bool unlink)
 1640{
 1641	struct net_device *dev, *tmp;
 
 1642
 1643	/* Remove the devices that don't need to be closed */
 1644	list_for_each_entry_safe(dev, tmp, head, close_list)
 1645		if (!(dev->flags & IFF_UP))
 1646			list_del_init(&dev->close_list);
 1647
 1648	__dev_close_many(head);
 1649
 1650	list_for_each_entry_safe(dev, tmp, head, close_list) {
 1651		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL);
 1652		call_netdevice_notifiers(NETDEV_DOWN, dev);
 1653		if (unlink)
 1654			list_del_init(&dev->close_list);
 1655	}
 
 
 
 
 1656}
 1657EXPORT_SYMBOL(dev_close_many);
 1658
 1659/**
 1660 *	dev_close - shutdown an interface.
 1661 *	@dev: device to shutdown
 1662 *
 1663 *	This function moves an active device into down state. A
 1664 *	%NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
 1665 *	is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
 1666 *	chain.
 1667 */
 1668void dev_close(struct net_device *dev)
 1669{
 1670	if (dev->flags & IFF_UP) {
 1671		LIST_HEAD(single);
 1672
 1673		list_add(&dev->close_list, &single);
 1674		dev_close_many(&single, true);
 1675		list_del(&single);
 1676	}
 
 1677}
 1678EXPORT_SYMBOL(dev_close);
 1679
 1680
 1681/**
 1682 *	dev_disable_lro - disable Large Receive Offload on a device
 1683 *	@dev: device
 1684 *
 1685 *	Disable Large Receive Offload (LRO) on a net device.  Must be
 1686 *	called under RTNL.  This is needed if received packets may be
 1687 *	forwarded to another interface.
 1688 */
 1689void dev_disable_lro(struct net_device *dev)
 1690{
 1691	struct net_device *lower_dev;
 1692	struct list_head *iter;
 1693
 1694	dev->wanted_features &= ~NETIF_F_LRO;
 1695	netdev_update_features(dev);
 
 
 
 
 1696
 
 
 
 
 
 
 
 
 
 1697	if (unlikely(dev->features & NETIF_F_LRO))
 1698		netdev_WARN(dev, "failed to disable LRO!\n");
 1699
 1700	netdev_for_each_lower_dev(dev, lower_dev, iter)
 1701		dev_disable_lro(lower_dev);
 1702}
 1703EXPORT_SYMBOL(dev_disable_lro);
 1704
 1705/**
 1706 *	dev_disable_gro_hw - disable HW Generic Receive Offload on a device
 1707 *	@dev: device
 1708 *
 1709 *	Disable HW Generic Receive Offload (GRO_HW) on a net device.  Must be
 1710 *	called under RTNL.  This is needed if Generic XDP is installed on
 1711 *	the device.
 1712 */
 1713static void dev_disable_gro_hw(struct net_device *dev)
 1714{
 1715	dev->wanted_features &= ~NETIF_F_GRO_HW;
 1716	netdev_update_features(dev);
 1717
 1718	if (unlikely(dev->features & NETIF_F_GRO_HW))
 1719		netdev_WARN(dev, "failed to disable GRO_HW!\n");
 1720}
 1721
 1722const char *netdev_cmd_to_name(enum netdev_cmd cmd)
 1723{
 1724#define N(val) 						\
 1725	case NETDEV_##val:				\
 1726		return "NETDEV_" __stringify(val);
 1727	switch (cmd) {
 1728	N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER)
 1729	N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE)
 1730	N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE)
 1731	N(POST_INIT) N(PRE_UNINIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN)
 1732	N(CHANGEUPPER) N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA)
 1733	N(BONDING_INFO) N(PRECHANGEUPPER) N(CHANGELOWERSTATE)
 1734	N(UDP_TUNNEL_PUSH_INFO) N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN)
 1735	N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO)
 1736	N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO)
 1737	N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE)
 1738	N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA)
 1739	N(XDP_FEAT_CHANGE)
 1740	}
 1741#undef N
 1742	return "UNKNOWN_NETDEV_EVENT";
 1743}
 1744EXPORT_SYMBOL_GPL(netdev_cmd_to_name);
 1745
 1746static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
 1747				   struct net_device *dev)
 1748{
 1749	struct netdev_notifier_info info = {
 1750		.dev = dev,
 1751	};
 1752
 1753	return nb->notifier_call(nb, val, &info);
 1754}
 1755
 1756static int call_netdevice_register_notifiers(struct notifier_block *nb,
 1757					     struct net_device *dev)
 1758{
 1759	int err;
 1760
 1761	err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
 1762	err = notifier_to_errno(err);
 1763	if (err)
 1764		return err;
 1765
 1766	if (!(dev->flags & IFF_UP))
 1767		return 0;
 1768
 1769	call_netdevice_notifier(nb, NETDEV_UP, dev);
 1770	return 0;
 1771}
 1772
 1773static void call_netdevice_unregister_notifiers(struct notifier_block *nb,
 1774						struct net_device *dev)
 1775{
 1776	if (dev->flags & IFF_UP) {
 1777		call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
 1778					dev);
 1779		call_netdevice_notifier(nb, NETDEV_DOWN, dev);
 1780	}
 1781	call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
 1782}
 1783
 1784static int call_netdevice_register_net_notifiers(struct notifier_block *nb,
 1785						 struct net *net)
 1786{
 1787	struct net_device *dev;
 1788	int err;
 1789
 1790	for_each_netdev(net, dev) {
 1791		err = call_netdevice_register_notifiers(nb, dev);
 1792		if (err)
 1793			goto rollback;
 1794	}
 1795	return 0;
 1796
 1797rollback:
 1798	for_each_netdev_continue_reverse(net, dev)
 1799		call_netdevice_unregister_notifiers(nb, dev);
 1800	return err;
 1801}
 1802
 1803static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb,
 1804						    struct net *net)
 1805{
 1806	struct net_device *dev;
 1807
 1808	for_each_netdev(net, dev)
 1809		call_netdevice_unregister_notifiers(nb, dev);
 1810}
 1811
 1812static int dev_boot_phase = 1;
 1813
 1814/**
 1815 * register_netdevice_notifier - register a network notifier block
 1816 * @nb: notifier
 1817 *
 1818 * Register a notifier to be called when network device events occur.
 1819 * The notifier passed is linked into the kernel structures and must
 1820 * not be reused until it has been unregistered. A negative errno code
 1821 * is returned on a failure.
 1822 *
 1823 * When registered all registration and up events are replayed
 1824 * to the new notifier to allow device to have a race free
 1825 * view of the network device list.
 1826 */
 1827
 1828int register_netdevice_notifier(struct notifier_block *nb)
 1829{
 
 
 1830	struct net *net;
 1831	int err;
 1832
 1833	/* Close race with setup_net() and cleanup_net() */
 1834	down_write(&pernet_ops_rwsem);
 1835	rtnl_lock();
 1836	err = raw_notifier_chain_register(&netdev_chain, nb);
 1837	if (err)
 1838		goto unlock;
 1839	if (dev_boot_phase)
 1840		goto unlock;
 1841	for_each_net(net) {
 1842		err = call_netdevice_register_net_notifiers(nb, net);
 1843		if (err)
 1844			goto rollback;
 
 
 
 
 
 
 
 
 1845	}
 1846
 1847unlock:
 1848	rtnl_unlock();
 1849	up_write(&pernet_ops_rwsem);
 1850	return err;
 1851
 1852rollback:
 1853	for_each_net_continue_reverse(net)
 1854		call_netdevice_unregister_net_notifiers(nb, net);
 
 
 
 
 
 
 
 
 
 
 
 
 1855
 1856	raw_notifier_chain_unregister(&netdev_chain, nb);
 1857	goto unlock;
 1858}
 1859EXPORT_SYMBOL(register_netdevice_notifier);
 1860
 1861/**
 1862 * unregister_netdevice_notifier - unregister a network notifier block
 1863 * @nb: notifier
 1864 *
 1865 * Unregister a notifier previously registered by
 1866 * register_netdevice_notifier(). The notifier is unlinked into the
 1867 * kernel structures and may then be reused. A negative errno code
 1868 * is returned on a failure.
 1869 *
 1870 * After unregistering unregister and down device events are synthesized
 1871 * for all devices on the device list to the removed notifier to remove
 1872 * the need for special case cleanup code.
 1873 */
 1874
 1875int unregister_netdevice_notifier(struct notifier_block *nb)
 1876{
 1877	struct net *net;
 1878	int err;
 1879
 1880	/* Close race with setup_net() and cleanup_net() */
 1881	down_write(&pernet_ops_rwsem);
 1882	rtnl_lock();
 1883	err = raw_notifier_chain_unregister(&netdev_chain, nb);
 1884	if (err)
 1885		goto unlock;
 1886
 1887	for_each_net(net)
 1888		call_netdevice_unregister_net_notifiers(nb, net);
 1889
 1890unlock:
 1891	rtnl_unlock();
 1892	up_write(&pernet_ops_rwsem);
 1893	return err;
 1894}
 1895EXPORT_SYMBOL(unregister_netdevice_notifier);
 1896
 1897static int __register_netdevice_notifier_net(struct net *net,
 1898					     struct notifier_block *nb,
 1899					     bool ignore_call_fail)
 1900{
 1901	int err;
 1902
 1903	err = raw_notifier_chain_register(&net->netdev_chain, nb);
 1904	if (err)
 1905		return err;
 1906	if (dev_boot_phase)
 1907		return 0;
 1908
 1909	err = call_netdevice_register_net_notifiers(nb, net);
 1910	if (err && !ignore_call_fail)
 1911		goto chain_unregister;
 1912
 1913	return 0;
 1914
 1915chain_unregister:
 1916	raw_notifier_chain_unregister(&net->netdev_chain, nb);
 1917	return err;
 1918}
 1919
 1920static int __unregister_netdevice_notifier_net(struct net *net,
 1921					       struct notifier_block *nb)
 1922{
 1923	int err;
 1924
 1925	err = raw_notifier_chain_unregister(&net->netdev_chain, nb);
 1926	if (err)
 1927		return err;
 1928
 1929	call_netdevice_unregister_net_notifiers(nb, net);
 1930	return 0;
 1931}
 1932
 1933/**
 1934 * register_netdevice_notifier_net - register a per-netns network notifier block
 1935 * @net: network namespace
 1936 * @nb: notifier
 1937 *
 1938 * Register a notifier to be called when network device events occur.
 1939 * The notifier passed is linked into the kernel structures and must
 1940 * not be reused until it has been unregistered. A negative errno code
 1941 * is returned on a failure.
 1942 *
 1943 * When registered all registration and up events are replayed
 1944 * to the new notifier to allow device to have a race free
 1945 * view of the network device list.
 1946 */
 1947
 1948int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb)
 1949{
 1950	int err;
 1951
 1952	rtnl_lock();
 1953	err = __register_netdevice_notifier_net(net, nb, false);
 1954	rtnl_unlock();
 1955	return err;
 1956}
 1957EXPORT_SYMBOL(register_netdevice_notifier_net);
 1958
 1959/**
 1960 * unregister_netdevice_notifier_net - unregister a per-netns
 1961 *                                     network notifier block
 1962 * @net: network namespace
 1963 * @nb: notifier
 1964 *
 1965 * Unregister a notifier previously registered by
 1966 * register_netdevice_notifier_net(). The notifier is unlinked from the
 1967 * kernel structures and may then be reused. A negative errno code
 1968 * is returned on a failure.
 1969 *
 1970 * After unregistering unregister and down device events are synthesized
 1971 * for all devices on the device list to the removed notifier to remove
 1972 * the need for special case cleanup code.
 1973 */
 1974
 1975int unregister_netdevice_notifier_net(struct net *net,
 1976				      struct notifier_block *nb)
 1977{
 1978	int err;
 1979
 1980	rtnl_lock();
 1981	err = __unregister_netdevice_notifier_net(net, nb);
 1982	rtnl_unlock();
 1983	return err;
 1984}
 1985EXPORT_SYMBOL(unregister_netdevice_notifier_net);
 1986
 1987static void __move_netdevice_notifier_net(struct net *src_net,
 1988					  struct net *dst_net,
 1989					  struct notifier_block *nb)
 1990{
 1991	__unregister_netdevice_notifier_net(src_net, nb);
 1992	__register_netdevice_notifier_net(dst_net, nb, true);
 1993}
 1994
 1995int register_netdevice_notifier_dev_net(struct net_device *dev,
 1996					struct notifier_block *nb,
 1997					struct netdev_net_notifier *nn)
 1998{
 1999	int err;
 2000
 2001	rtnl_lock();
 2002	err = __register_netdevice_notifier_net(dev_net(dev), nb, false);
 2003	if (!err) {
 2004		nn->nb = nb;
 2005		list_add(&nn->list, &dev->net_notifier_list);
 2006	}
 2007	rtnl_unlock();
 2008	return err;
 2009}
 2010EXPORT_SYMBOL(register_netdevice_notifier_dev_net);
 2011
 2012int unregister_netdevice_notifier_dev_net(struct net_device *dev,
 2013					  struct notifier_block *nb,
 2014					  struct netdev_net_notifier *nn)
 2015{
 2016	int err;
 2017
 2018	rtnl_lock();
 2019	list_del(&nn->list);
 2020	err = __unregister_netdevice_notifier_net(dev_net(dev), nb);
 2021	rtnl_unlock();
 2022	return err;
 2023}
 2024EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net);
 2025
 2026static void move_netdevice_notifiers_dev_net(struct net_device *dev,
 2027					     struct net *net)
 2028{
 2029	struct netdev_net_notifier *nn;
 2030
 2031	list_for_each_entry(nn, &dev->net_notifier_list, list)
 2032		__move_netdevice_notifier_net(dev_net(dev), net, nn->nb);
 2033}
 2034
 2035/**
 2036 *	call_netdevice_notifiers_info - call all network notifier blocks
 2037 *	@val: value passed unmodified to notifier function
 2038 *	@info: notifier information data
 2039 *
 2040 *	Call all network notifier blocks.  Parameters and return value
 2041 *	are as for raw_notifier_call_chain().
 2042 */
 2043
 2044int call_netdevice_notifiers_info(unsigned long val,
 2045				  struct netdev_notifier_info *info)
 2046{
 2047	struct net *net = dev_net(info->dev);
 2048	int ret;
 2049
 2050	ASSERT_RTNL();
 2051
 2052	/* Run per-netns notifier block chain first, then run the global one.
 2053	 * Hopefully, one day, the global one is going to be removed after
 2054	 * all notifier block registrators get converted to be per-netns.
 2055	 */
 2056	ret = raw_notifier_call_chain(&net->netdev_chain, val, info);
 2057	if (ret & NOTIFY_STOP_MASK)
 2058		return ret;
 2059	return raw_notifier_call_chain(&netdev_chain, val, info);
 2060}
 2061
 2062/**
 2063 *	call_netdevice_notifiers_info_robust - call per-netns notifier blocks
 2064 *	                                       for and rollback on error
 2065 *	@val_up: value passed unmodified to notifier function
 2066 *	@val_down: value passed unmodified to the notifier function when
 2067 *	           recovering from an error on @val_up
 2068 *	@info: notifier information data
 2069 *
 2070 *	Call all per-netns network notifier blocks, but not notifier blocks on
 2071 *	the global notifier chain. Parameters and return value are as for
 2072 *	raw_notifier_call_chain_robust().
 2073 */
 2074
 2075static int
 2076call_netdevice_notifiers_info_robust(unsigned long val_up,
 2077				     unsigned long val_down,
 2078				     struct netdev_notifier_info *info)
 2079{
 2080	struct net *net = dev_net(info->dev);
 2081
 2082	ASSERT_RTNL();
 2083
 2084	return raw_notifier_call_chain_robust(&net->netdev_chain,
 2085					      val_up, val_down, info);
 2086}
 2087
 2088static int call_netdevice_notifiers_extack(unsigned long val,
 2089					   struct net_device *dev,
 2090					   struct netlink_ext_ack *extack)
 2091{
 2092	struct netdev_notifier_info info = {
 2093		.dev = dev,
 2094		.extack = extack,
 2095	};
 2096
 2097	return call_netdevice_notifiers_info(val, &info);
 2098}
 2099
 2100/**
 2101 *	call_netdevice_notifiers - call all network notifier blocks
 2102 *      @val: value passed unmodified to notifier function
 2103 *      @dev: net_device pointer passed unmodified to notifier function
 2104 *
 2105 *	Call all network notifier blocks.  Parameters and return value
 2106 *	are as for raw_notifier_call_chain().
 2107 */
 2108
 2109int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
 2110{
 2111	return call_netdevice_notifiers_extack(val, dev, NULL);
 
 2112}
 2113EXPORT_SYMBOL(call_netdevice_notifiers);
 2114
 2115/**
 2116 *	call_netdevice_notifiers_mtu - call all network notifier blocks
 2117 *	@val: value passed unmodified to notifier function
 2118 *	@dev: net_device pointer passed unmodified to notifier function
 2119 *	@arg: additional u32 argument passed to the notifier function
 2120 *
 2121 *	Call all network notifier blocks.  Parameters and return value
 2122 *	are as for raw_notifier_call_chain().
 2123 */
 2124static int call_netdevice_notifiers_mtu(unsigned long val,
 2125					struct net_device *dev, u32 arg)
 2126{
 2127	struct netdev_notifier_info_ext info = {
 2128		.info.dev = dev,
 2129		.ext.mtu = arg,
 2130	};
 2131
 2132	BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0);
 2133
 2134	return call_netdevice_notifiers_info(val, &info.info);
 2135}
 2136
 2137#ifdef CONFIG_NET_INGRESS
 2138static DEFINE_STATIC_KEY_FALSE(ingress_needed_key);
 2139
 2140void net_inc_ingress_queue(void)
 2141{
 2142	static_branch_inc(&ingress_needed_key);
 2143}
 2144EXPORT_SYMBOL_GPL(net_inc_ingress_queue);
 2145
 2146void net_dec_ingress_queue(void)
 2147{
 2148	static_branch_dec(&ingress_needed_key);
 2149}
 2150EXPORT_SYMBOL_GPL(net_dec_ingress_queue);
 2151#endif
 2152
 2153#ifdef CONFIG_NET_EGRESS
 2154static DEFINE_STATIC_KEY_FALSE(egress_needed_key);
 2155
 2156void net_inc_egress_queue(void)
 2157{
 2158	static_branch_inc(&egress_needed_key);
 2159}
 2160EXPORT_SYMBOL_GPL(net_inc_egress_queue);
 2161
 2162void net_dec_egress_queue(void)
 2163{
 2164	static_branch_dec(&egress_needed_key);
 2165}
 2166EXPORT_SYMBOL_GPL(net_dec_egress_queue);
 2167#endif
 2168
 2169#ifdef CONFIG_NET_CLS_ACT
 2170DEFINE_STATIC_KEY_FALSE(tcf_sw_enabled_key);
 2171EXPORT_SYMBOL(tcf_sw_enabled_key);
 2172#endif
 2173
 2174DEFINE_STATIC_KEY_FALSE(netstamp_needed_key);
 2175EXPORT_SYMBOL(netstamp_needed_key);
 2176#ifdef CONFIG_JUMP_LABEL
 2177static atomic_t netstamp_needed_deferred;
 2178static atomic_t netstamp_wanted;
 2179static void netstamp_clear(struct work_struct *work)
 2180{
 2181	int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
 2182	int wanted;
 2183
 2184	wanted = atomic_add_return(deferred, &netstamp_wanted);
 2185	if (wanted > 0)
 2186		static_branch_enable(&netstamp_needed_key);
 2187	else
 2188		static_branch_disable(&netstamp_needed_key);
 2189}
 2190static DECLARE_WORK(netstamp_work, netstamp_clear);
 2191#endif
 2192
 2193void net_enable_timestamp(void)
 2194{
 2195#ifdef CONFIG_JUMP_LABEL
 2196	int wanted = atomic_read(&netstamp_wanted);
 2197
 2198	while (wanted > 0) {
 2199		if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted + 1))
 2200			return;
 2201	}
 2202	atomic_inc(&netstamp_needed_deferred);
 2203	schedule_work(&netstamp_work);
 2204#else
 2205	static_branch_inc(&netstamp_needed_key);
 2206#endif
 2207}
 2208EXPORT_SYMBOL(net_enable_timestamp);
 2209
 2210void net_disable_timestamp(void)
 2211{
 2212#ifdef CONFIG_JUMP_LABEL
 2213	int wanted = atomic_read(&netstamp_wanted);
 2214
 2215	while (wanted > 1) {
 2216		if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted - 1))
 2217			return;
 2218	}
 2219	atomic_dec(&netstamp_needed_deferred);
 2220	schedule_work(&netstamp_work);
 2221#else
 2222	static_branch_dec(&netstamp_needed_key);
 2223#endif
 2224}
 2225EXPORT_SYMBOL(net_disable_timestamp);
 2226
 2227static inline void net_timestamp_set(struct sk_buff *skb)
 2228{
 2229	skb->tstamp = 0;
 2230	skb->tstamp_type = SKB_CLOCK_REALTIME;
 2231	if (static_branch_unlikely(&netstamp_needed_key))
 2232		skb->tstamp = ktime_get_real();
 2233}
 2234
 2235#define net_timestamp_check(COND, SKB)				\
 2236	if (static_branch_unlikely(&netstamp_needed_key)) {	\
 2237		if ((COND) && !(SKB)->tstamp)			\
 2238			(SKB)->tstamp = ktime_get_real();	\
 2239	}							\
 2240
 2241bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb)
 2242{
 2243	return __is_skb_forwardable(dev, skb, true);
 
 2244}
 2245EXPORT_SYMBOL_GPL(is_skb_forwardable);
 2246
 2247static int __dev_forward_skb2(struct net_device *dev, struct sk_buff *skb,
 2248			      bool check_mtu)
 2249{
 2250	int ret = ____dev_forward_skb(dev, skb, check_mtu);
 2251
 2252	if (likely(!ret)) {
 2253		skb->protocol = eth_type_trans(skb, dev);
 2254		skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
 2255	}
 2256
 2257	return ret;
 2258}
 
 2259
 2260int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
 2261{
 2262	return __dev_forward_skb2(dev, skb, true);
 
 
 
 
 2263}
 2264EXPORT_SYMBOL_GPL(__dev_forward_skb);
 2265
 2266/**
 2267 * dev_forward_skb - loopback an skb to another netif
 2268 *
 2269 * @dev: destination network device
 2270 * @skb: buffer to forward
 2271 *
 2272 * return values:
 2273 *	NET_RX_SUCCESS	(no congestion)
 2274 *	NET_RX_DROP     (packet was dropped, but freed)
 2275 *
 2276 * dev_forward_skb can be used for injecting an skb from the
 2277 * start_xmit function of one device into the receive queue
 2278 * of another device.
 2279 *
 2280 * The receiving device may be in another namespace, so
 2281 * we have to clear all information in the skb that could
 2282 * impact namespace isolation.
 2283 */
 2284int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
 2285{
 2286	return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
 2287}
 2288EXPORT_SYMBOL_GPL(dev_forward_skb);
 
 
 
 
 2289
 2290int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb)
 2291{
 2292	return __dev_forward_skb2(dev, skb, false) ?: netif_rx_internal(skb);
 
 
 
 
 
 
 
 
 
 
 2293}
 
 2294
 2295static inline int deliver_skb(struct sk_buff *skb,
 2296			      struct packet_type *pt_prev,
 2297			      struct net_device *orig_dev)
 2298{
 2299	if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC)))
 2300		return -ENOMEM;
 2301	refcount_inc(&skb->users);
 2302	return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
 2303}
 2304
 2305static inline void deliver_ptype_list_skb(struct sk_buff *skb,
 2306					  struct packet_type **pt,
 2307					  struct net_device *orig_dev,
 2308					  __be16 type,
 2309					  struct list_head *ptype_list)
 2310{
 2311	struct packet_type *ptype, *pt_prev = *pt;
 2312
 2313	list_for_each_entry_rcu(ptype, ptype_list, list) {
 2314		if (ptype->type != type)
 2315			continue;
 2316		if (pt_prev)
 2317			deliver_skb(skb, pt_prev, orig_dev);
 2318		pt_prev = ptype;
 2319	}
 2320	*pt = pt_prev;
 2321}
 2322
 2323static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
 2324{
 2325	if (!ptype->af_packet_priv || !skb->sk)
 2326		return false;
 2327
 2328	if (ptype->id_match)
 2329		return ptype->id_match(ptype, skb->sk);
 2330	else if ((struct sock *)ptype->af_packet_priv == skb->sk)
 2331		return true;
 2332
 2333	return false;
 2334}
 2335
 2336/**
 2337 * dev_nit_active - return true if any network interface taps are in use
 2338 *
 2339 * @dev: network device to check for the presence of taps
 2340 */
 2341bool dev_nit_active(struct net_device *dev)
 2342{
 2343	return !list_empty(&net_hotdata.ptype_all) ||
 2344	       !list_empty(&dev->ptype_all);
 2345}
 2346EXPORT_SYMBOL_GPL(dev_nit_active);
 2347
 2348/*
 2349 *	Support routine. Sends outgoing frames to any network
 2350 *	taps currently in use.
 2351 */
 2352
 2353void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
 2354{
 2355	struct list_head *ptype_list = &net_hotdata.ptype_all;
 2356	struct packet_type *ptype, *pt_prev = NULL;
 2357	struct sk_buff *skb2 = NULL;
 
 2358
 2359	rcu_read_lock();
 2360again:
 2361	list_for_each_entry_rcu(ptype, ptype_list, list) {
 2362		if (READ_ONCE(ptype->ignore_outgoing))
 2363			continue;
 2364
 2365		/* Never send packets back to the socket
 2366		 * they originated from - MvS (miquels@drinkel.ow.org)
 2367		 */
 2368		if (skb_loop_sk(ptype, skb))
 2369			continue;
 
 
 
 
 
 
 2370
 2371		if (pt_prev) {
 2372			deliver_skb(skb2, pt_prev, skb->dev);
 2373			pt_prev = ptype;
 2374			continue;
 2375		}
 2376
 2377		/* need to clone skb, done only once */
 2378		skb2 = skb_clone(skb, GFP_ATOMIC);
 2379		if (!skb2)
 2380			goto out_unlock;
 2381
 2382		net_timestamp_set(skb2);
 2383
 2384		/* skb->nh should be correctly
 2385		 * set by sender, so that the second statement is
 2386		 * just protection against buggy protocols.
 2387		 */
 2388		skb_reset_mac_header(skb2);
 2389
 2390		if (skb_network_header(skb2) < skb2->data ||
 2391		    skb_network_header(skb2) > skb_tail_pointer(skb2)) {
 2392			net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
 2393					     ntohs(skb2->protocol),
 2394					     dev->name);
 2395			skb_reset_network_header(skb2);
 2396		}
 2397
 2398		skb2->transport_header = skb2->network_header;
 2399		skb2->pkt_type = PACKET_OUTGOING;
 2400		pt_prev = ptype;
 2401	}
 
 
 
 
 
 2402
 2403	if (ptype_list == &net_hotdata.ptype_all) {
 2404		ptype_list = &dev->ptype_all;
 2405		goto again;
 2406	}
 2407out_unlock:
 2408	if (pt_prev) {
 2409		if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC))
 2410			pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
 2411		else
 2412			kfree_skb(skb2);
 2413	}
 
 
 2414	rcu_read_unlock();
 2415}
 2416EXPORT_SYMBOL_GPL(dev_queue_xmit_nit);
 2417
 2418/**
 2419 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
 2420 * @dev: Network device
 2421 * @txq: number of queues available
 2422 *
 2423 * If real_num_tx_queues is changed the tc mappings may no longer be
 2424 * valid. To resolve this verify the tc mapping remains valid and if
 2425 * not NULL the mapping. With no priorities mapping to this
 2426 * offset/count pair it will no longer be used. In the worst case TC0
 2427 * is invalid nothing can be done so disable priority mappings. If is
 2428 * expected that drivers will fix this mapping if they can before
 2429 * calling netif_set_real_num_tx_queues.
 2430 */
 2431static void netif_setup_tc(struct net_device *dev, unsigned int txq)
 2432{
 2433	int i;
 2434	struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
 2435
 2436	/* If TC0 is invalidated disable TC mapping */
 2437	if (tc->offset + tc->count > txq) {
 2438		netdev_warn(dev, "Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
 
 
 2439		dev->num_tc = 0;
 2440		return;
 2441	}
 2442
 2443	/* Invalidated prio to tc mappings set to TC0 */
 2444	for (i = 1; i < TC_BITMASK + 1; i++) {
 2445		int q = netdev_get_prio_tc_map(dev, i);
 2446
 2447		tc = &dev->tc_to_txq[q];
 2448		if (tc->offset + tc->count > txq) {
 2449			netdev_warn(dev, "Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
 2450				    i, q);
 
 
 
 2451			netdev_set_prio_tc_map(dev, i, 0);
 2452		}
 2453	}
 2454}
 2455
 2456int netdev_txq_to_tc(struct net_device *dev, unsigned int txq)
 2457{
 2458	if (dev->num_tc) {
 2459		struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
 2460		int i;
 2461
 2462		/* walk through the TCs and see if it falls into any of them */
 2463		for (i = 0; i < TC_MAX_QUEUE; i++, tc++) {
 2464			if ((txq - tc->offset) < tc->count)
 2465				return i;
 2466		}
 2467
 2468		/* didn't find it, just return -1 to indicate no match */
 2469		return -1;
 2470	}
 2471
 2472	return 0;
 2473}
 2474EXPORT_SYMBOL(netdev_txq_to_tc);
 2475
 2476#ifdef CONFIG_XPS
 2477static struct static_key xps_needed __read_mostly;
 2478static struct static_key xps_rxqs_needed __read_mostly;
 2479static DEFINE_MUTEX(xps_map_mutex);
 2480#define xmap_dereference(P)		\
 2481	rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
 2482
 2483static bool remove_xps_queue(struct xps_dev_maps *dev_maps,
 2484			     struct xps_dev_maps *old_maps, int tci, u16 index)
 2485{
 2486	struct xps_map *map = NULL;
 2487	int pos;
 2488
 2489	map = xmap_dereference(dev_maps->attr_map[tci]);
 2490	if (!map)
 2491		return false;
 2492
 2493	for (pos = map->len; pos--;) {
 2494		if (map->queues[pos] != index)
 2495			continue;
 2496
 2497		if (map->len > 1) {
 2498			map->queues[pos] = map->queues[--map->len];
 2499			break;
 2500		}
 2501
 2502		if (old_maps)
 2503			RCU_INIT_POINTER(old_maps->attr_map[tci], NULL);
 2504		RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL);
 2505		kfree_rcu(map, rcu);
 2506		return false;
 2507	}
 2508
 2509	return true;
 2510}
 2511
 2512static bool remove_xps_queue_cpu(struct net_device *dev,
 2513				 struct xps_dev_maps *dev_maps,
 2514				 int cpu, u16 offset, u16 count)
 2515{
 2516	int num_tc = dev_maps->num_tc;
 2517	bool active = false;
 2518	int tci;
 2519
 2520	for (tci = cpu * num_tc; num_tc--; tci++) {
 2521		int i, j;
 2522
 2523		for (i = count, j = offset; i--; j++) {
 2524			if (!remove_xps_queue(dev_maps, NULL, tci, j))
 2525				break;
 2526		}
 2527
 2528		active |= i < 0;
 2529	}
 2530
 2531	return active;
 2532}
 2533
 2534static void reset_xps_maps(struct net_device *dev,
 2535			   struct xps_dev_maps *dev_maps,
 2536			   enum xps_map_type type)
 2537{
 2538	static_key_slow_dec_cpuslocked(&xps_needed);
 2539	if (type == XPS_RXQS)
 2540		static_key_slow_dec_cpuslocked(&xps_rxqs_needed);
 2541
 2542	RCU_INIT_POINTER(dev->xps_maps[type], NULL);
 2543
 2544	kfree_rcu(dev_maps, rcu);
 2545}
 2546
 2547static void clean_xps_maps(struct net_device *dev, enum xps_map_type type,
 2548			   u16 offset, u16 count)
 2549{
 2550	struct xps_dev_maps *dev_maps;
 2551	bool active = false;
 2552	int i, j;
 2553
 2554	dev_maps = xmap_dereference(dev->xps_maps[type]);
 2555	if (!dev_maps)
 2556		return;
 2557
 2558	for (j = 0; j < dev_maps->nr_ids; j++)
 2559		active |= remove_xps_queue_cpu(dev, dev_maps, j, offset, count);
 2560	if (!active)
 2561		reset_xps_maps(dev, dev_maps, type);
 2562
 2563	if (type == XPS_CPUS) {
 2564		for (i = offset + (count - 1); count--; i--)
 2565			netdev_queue_numa_node_write(
 2566				netdev_get_tx_queue(dev, i), NUMA_NO_NODE);
 2567	}
 2568}
 2569
 2570static void netif_reset_xps_queues(struct net_device *dev, u16 offset,
 2571				   u16 count)
 2572{
 2573	if (!static_key_false(&xps_needed))
 2574		return;
 2575
 2576	cpus_read_lock();
 2577	mutex_lock(&xps_map_mutex);
 2578
 2579	if (static_key_false(&xps_rxqs_needed))
 2580		clean_xps_maps(dev, XPS_RXQS, offset, count);
 2581
 2582	clean_xps_maps(dev, XPS_CPUS, offset, count);
 2583
 2584	mutex_unlock(&xps_map_mutex);
 2585	cpus_read_unlock();
 2586}
 2587
 2588static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
 2589{
 2590	netif_reset_xps_queues(dev, index, dev->num_tx_queues - index);
 2591}
 2592
 2593static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index,
 2594				      u16 index, bool is_rxqs_map)
 2595{
 2596	struct xps_map *new_map;
 2597	int alloc_len = XPS_MIN_MAP_ALLOC;
 2598	int i, pos;
 2599
 2600	for (pos = 0; map && pos < map->len; pos++) {
 2601		if (map->queues[pos] != index)
 2602			continue;
 2603		return map;
 2604	}
 2605
 2606	/* Need to add tx-queue to this CPU's/rx-queue's existing map */
 2607	if (map) {
 2608		if (pos < map->alloc_len)
 2609			return map;
 2610
 2611		alloc_len = map->alloc_len * 2;
 2612	}
 2613
 2614	/* Need to allocate new map to store tx-queue on this CPU's/rx-queue's
 2615	 *  map
 2616	 */
 2617	if (is_rxqs_map)
 2618		new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL);
 2619	else
 2620		new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
 2621				       cpu_to_node(attr_index));
 2622	if (!new_map)
 2623		return NULL;
 2624
 2625	for (i = 0; i < pos; i++)
 2626		new_map->queues[i] = map->queues[i];
 2627	new_map->alloc_len = alloc_len;
 2628	new_map->len = pos;
 2629
 2630	return new_map;
 2631}
 2632
 2633/* Copy xps maps at a given index */
 2634static void xps_copy_dev_maps(struct xps_dev_maps *dev_maps,
 2635			      struct xps_dev_maps *new_dev_maps, int index,
 2636			      int tc, bool skip_tc)
 2637{
 2638	int i, tci = index * dev_maps->num_tc;
 2639	struct xps_map *map;
 2640
 2641	/* copy maps belonging to foreign traffic classes */
 2642	for (i = 0; i < dev_maps->num_tc; i++, tci++) {
 2643		if (i == tc && skip_tc)
 2644			continue;
 2645
 2646		/* fill in the new device map from the old device map */
 2647		map = xmap_dereference(dev_maps->attr_map[tci]);
 2648		RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);
 2649	}
 2650}
 2651
 2652/* Must be called under cpus_read_lock */
 2653int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask,
 2654			  u16 index, enum xps_map_type type)
 2655{
 2656	struct xps_dev_maps *dev_maps, *new_dev_maps = NULL, *old_dev_maps = NULL;
 2657	const unsigned long *online_mask = NULL;
 2658	bool active = false, copy = false;
 2659	int i, j, tci, numa_node_id = -2;
 2660	int maps_sz, num_tc = 1, tc = 0;
 2661	struct xps_map *map, *new_map;
 2662	unsigned int nr_ids;
 2663
 2664	WARN_ON_ONCE(index >= dev->num_tx_queues);
 2665
 2666	if (dev->num_tc) {
 2667		/* Do not allow XPS on subordinate device directly */
 2668		num_tc = dev->num_tc;
 2669		if (num_tc < 0)
 2670			return -EINVAL;
 2671
 2672		/* If queue belongs to subordinate dev use its map */
 2673		dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev;
 2674
 2675		tc = netdev_txq_to_tc(dev, index);
 2676		if (tc < 0)
 2677			return -EINVAL;
 2678	}
 2679
 2680	mutex_lock(&xps_map_mutex);
 2681
 2682	dev_maps = xmap_dereference(dev->xps_maps[type]);
 2683	if (type == XPS_RXQS) {
 2684		maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues);
 2685		nr_ids = dev->num_rx_queues;
 2686	} else {
 2687		maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc);
 2688		if (num_possible_cpus() > 1)
 2689			online_mask = cpumask_bits(cpu_online_mask);
 2690		nr_ids = nr_cpu_ids;
 2691	}
 2692
 2693	if (maps_sz < L1_CACHE_BYTES)
 2694		maps_sz = L1_CACHE_BYTES;
 2695
 2696	/* The old dev_maps could be larger or smaller than the one we're
 2697	 * setting up now, as dev->num_tc or nr_ids could have been updated in
 2698	 * between. We could try to be smart, but let's be safe instead and only
 2699	 * copy foreign traffic classes if the two map sizes match.
 2700	 */
 2701	if (dev_maps &&
 2702	    dev_maps->num_tc == num_tc && dev_maps->nr_ids == nr_ids)
 2703		copy = true;
 2704
 2705	/* allocate memory for queue storage */
 2706	for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids),
 2707	     j < nr_ids;) {
 2708		if (!new_dev_maps) {
 2709			new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
 2710			if (!new_dev_maps) {
 2711				mutex_unlock(&xps_map_mutex);
 2712				return -ENOMEM;
 2713			}
 2714
 2715			new_dev_maps->nr_ids = nr_ids;
 2716			new_dev_maps->num_tc = num_tc;
 2717		}
 2718
 2719		tci = j * num_tc + tc;
 2720		map = copy ? xmap_dereference(dev_maps->attr_map[tci]) : NULL;
 2721
 2722		map = expand_xps_map(map, j, index, type == XPS_RXQS);
 2723		if (!map)
 2724			goto error;
 2725
 2726		RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);
 2727	}
 2728
 2729	if (!new_dev_maps)
 2730		goto out_no_new_maps;
 2731
 2732	if (!dev_maps) {
 2733		/* Increment static keys at most once per type */
 2734		static_key_slow_inc_cpuslocked(&xps_needed);
 2735		if (type == XPS_RXQS)
 2736			static_key_slow_inc_cpuslocked(&xps_rxqs_needed);
 2737	}
 2738
 2739	for (j = 0; j < nr_ids; j++) {
 2740		bool skip_tc = false;
 2741
 2742		tci = j * num_tc + tc;
 2743		if (netif_attr_test_mask(j, mask, nr_ids) &&
 2744		    netif_attr_test_online(j, online_mask, nr_ids)) {
 2745			/* add tx-queue to CPU/rx-queue maps */
 2746			int pos = 0;
 2747
 2748			skip_tc = true;
 2749
 2750			map = xmap_dereference(new_dev_maps->attr_map[tci]);
 2751			while ((pos < map->len) && (map->queues[pos] != index))
 2752				pos++;
 2753
 2754			if (pos == map->len)
 2755				map->queues[map->len++] = index;
 2756#ifdef CONFIG_NUMA
 2757			if (type == XPS_CPUS) {
 2758				if (numa_node_id == -2)
 2759					numa_node_id = cpu_to_node(j);
 2760				else if (numa_node_id != cpu_to_node(j))
 2761					numa_node_id = -1;
 2762			}
 2763#endif
 2764		}
 2765
 2766		if (copy)
 2767			xps_copy_dev_maps(dev_maps, new_dev_maps, j, tc,
 2768					  skip_tc);
 2769	}
 2770
 2771	rcu_assign_pointer(dev->xps_maps[type], new_dev_maps);
 2772
 2773	/* Cleanup old maps */
 2774	if (!dev_maps)
 2775		goto out_no_old_maps;
 2776
 2777	for (j = 0; j < dev_maps->nr_ids; j++) {
 2778		for (i = num_tc, tci = j * dev_maps->num_tc; i--; tci++) {
 2779			map = xmap_dereference(dev_maps->attr_map[tci]);
 2780			if (!map)
 2781				continue;
 2782
 2783			if (copy) {
 2784				new_map = xmap_dereference(new_dev_maps->attr_map[tci]);
 2785				if (map == new_map)
 2786					continue;
 2787			}
 2788
 2789			RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL);
 2790			kfree_rcu(map, rcu);
 2791		}
 2792	}
 2793
 2794	old_dev_maps = dev_maps;
 2795
 2796out_no_old_maps:
 2797	dev_maps = new_dev_maps;
 2798	active = true;
 2799
 2800out_no_new_maps:
 2801	if (type == XPS_CPUS)
 2802		/* update Tx queue numa node */
 2803		netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
 2804					     (numa_node_id >= 0) ?
 2805					     numa_node_id : NUMA_NO_NODE);
 2806
 2807	if (!dev_maps)
 2808		goto out_no_maps;
 2809
 2810	/* removes tx-queue from unused CPUs/rx-queues */
 2811	for (j = 0; j < dev_maps->nr_ids; j++) {
 2812		tci = j * dev_maps->num_tc;
 2813
 2814		for (i = 0; i < dev_maps->num_tc; i++, tci++) {
 2815			if (i == tc &&
 2816			    netif_attr_test_mask(j, mask, dev_maps->nr_ids) &&
 2817			    netif_attr_test_online(j, online_mask, dev_maps->nr_ids))
 2818				continue;
 2819
 2820			active |= remove_xps_queue(dev_maps,
 2821						   copy ? old_dev_maps : NULL,
 2822						   tci, index);
 2823		}
 2824	}
 2825
 2826	if (old_dev_maps)
 2827		kfree_rcu(old_dev_maps, rcu);
 2828
 2829	/* free map if not active */
 2830	if (!active)
 2831		reset_xps_maps(dev, dev_maps, type);
 2832
 2833out_no_maps:
 2834	mutex_unlock(&xps_map_mutex);
 2835
 2836	return 0;
 2837error:
 2838	/* remove any maps that we added */
 2839	for (j = 0; j < nr_ids; j++) {
 2840		for (i = num_tc, tci = j * num_tc; i--; tci++) {
 2841			new_map = xmap_dereference(new_dev_maps->attr_map[tci]);
 2842			map = copy ?
 2843			      xmap_dereference(dev_maps->attr_map[tci]) :
 2844			      NULL;
 2845			if (new_map && new_map != map)
 2846				kfree(new_map);
 2847		}
 2848	}
 2849
 2850	mutex_unlock(&xps_map_mutex);
 2851
 2852	kfree(new_dev_maps);
 2853	return -ENOMEM;
 2854}
 2855EXPORT_SYMBOL_GPL(__netif_set_xps_queue);
 2856
 2857int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
 2858			u16 index)
 2859{
 2860	int ret;
 2861
 2862	cpus_read_lock();
 2863	ret =  __netif_set_xps_queue(dev, cpumask_bits(mask), index, XPS_CPUS);
 2864	cpus_read_unlock();
 2865
 2866	return ret;
 2867}
 2868EXPORT_SYMBOL(netif_set_xps_queue);
 2869
 2870#endif
 2871static void netdev_unbind_all_sb_channels(struct net_device *dev)
 2872{
 2873	struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues];
 2874
 2875	/* Unbind any subordinate channels */
 2876	while (txq-- != &dev->_tx[0]) {
 2877		if (txq->sb_dev)
 2878			netdev_unbind_sb_channel(dev, txq->sb_dev);
 2879	}
 2880}
 2881
 2882void netdev_reset_tc(struct net_device *dev)
 2883{
 2884#ifdef CONFIG_XPS
 2885	netif_reset_xps_queues_gt(dev, 0);
 2886#endif
 2887	netdev_unbind_all_sb_channels(dev);
 2888
 2889	/* Reset TC configuration of device */
 2890	dev->num_tc = 0;
 2891	memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq));
 2892	memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map));
 2893}
 2894EXPORT_SYMBOL(netdev_reset_tc);
 2895
 2896int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset)
 2897{
 2898	if (tc >= dev->num_tc)
 2899		return -EINVAL;
 2900
 2901#ifdef CONFIG_XPS
 2902	netif_reset_xps_queues(dev, offset, count);
 2903#endif
 2904	dev->tc_to_txq[tc].count = count;
 2905	dev->tc_to_txq[tc].offset = offset;
 2906	return 0;
 2907}
 2908EXPORT_SYMBOL(netdev_set_tc_queue);
 2909
 2910int netdev_set_num_tc(struct net_device *dev, u8 num_tc)
 2911{
 2912	if (num_tc > TC_MAX_QUEUE)
 2913		return -EINVAL;
 2914
 2915#ifdef CONFIG_XPS
 2916	netif_reset_xps_queues_gt(dev, 0);
 2917#endif
 2918	netdev_unbind_all_sb_channels(dev);
 2919
 2920	dev->num_tc = num_tc;
 2921	return 0;
 2922}
 2923EXPORT_SYMBOL(netdev_set_num_tc);
 2924
 2925void netdev_unbind_sb_channel(struct net_device *dev,
 2926			      struct net_device *sb_dev)
 2927{
 2928	struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues];
 2929
 2930#ifdef CONFIG_XPS
 2931	netif_reset_xps_queues_gt(sb_dev, 0);
 2932#endif
 2933	memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq));
 2934	memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map));
 2935
 2936	while (txq-- != &dev->_tx[0]) {
 2937		if (txq->sb_dev == sb_dev)
 2938			txq->sb_dev = NULL;
 2939	}
 2940}
 2941EXPORT_SYMBOL(netdev_unbind_sb_channel);
 2942
 2943int netdev_bind_sb_channel_queue(struct net_device *dev,
 2944				 struct net_device *sb_dev,
 2945				 u8 tc, u16 count, u16 offset)
 2946{
 2947	/* Make certain the sb_dev and dev are already configured */
 2948	if (sb_dev->num_tc >= 0 || tc >= dev->num_tc)
 2949		return -EINVAL;
 2950
 2951	/* We cannot hand out queues we don't have */
 2952	if ((offset + count) > dev->real_num_tx_queues)
 2953		return -EINVAL;
 2954
 2955	/* Record the mapping */
 2956	sb_dev->tc_to_txq[tc].count = count;
 2957	sb_dev->tc_to_txq[tc].offset = offset;
 2958
 2959	/* Provide a way for Tx queue to find the tc_to_txq map or
 2960	 * XPS map for itself.
 2961	 */
 2962	while (count--)
 2963		netdev_get_tx_queue(dev, count + offset)->sb_dev = sb_dev;
 2964
 2965	return 0;
 2966}
 2967EXPORT_SYMBOL(netdev_bind_sb_channel_queue);
 2968
 2969int netdev_set_sb_channel(struct net_device *dev, u16 channel)
 2970{
 2971	/* Do not use a multiqueue device to represent a subordinate channel */
 2972	if (netif_is_multiqueue(dev))
 2973		return -ENODEV;
 2974
 2975	/* We allow channels 1 - 32767 to be used for subordinate channels.
 2976	 * Channel 0 is meant to be "native" mode and used only to represent
 2977	 * the main root device. We allow writing 0 to reset the device back
 2978	 * to normal mode after being used as a subordinate channel.
 2979	 */
 2980	if (channel > S16_MAX)
 2981		return -EINVAL;
 2982
 2983	dev->num_tc = -channel;
 2984
 2985	return 0;
 2986}
 2987EXPORT_SYMBOL(netdev_set_sb_channel);
 2988
 2989/*
 2990 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
 2991 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed.
 2992 */
 2993int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
 2994{
 2995	bool disabling;
 2996	int rc;
 2997
 2998	disabling = txq < dev->real_num_tx_queues;
 2999
 3000	if (txq < 1 || txq > dev->num_tx_queues)
 3001		return -EINVAL;
 3002
 3003	if (dev->reg_state == NETREG_REGISTERED ||
 3004	    dev->reg_state == NETREG_UNREGISTERING) {
 3005		ASSERT_RTNL();
 3006
 3007		rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
 3008						  txq);
 3009		if (rc)
 3010			return rc;
 3011
 3012		if (dev->num_tc)
 3013			netif_setup_tc(dev, txq);
 3014
 3015		net_shaper_set_real_num_tx_queues(dev, txq);
 3016
 3017		dev_qdisc_change_real_num_tx(dev, txq);
 3018
 3019		dev->real_num_tx_queues = txq;
 3020
 3021		if (disabling) {
 3022			synchronize_net();
 3023			qdisc_reset_all_tx_gt(dev, txq);
 3024#ifdef CONFIG_XPS
 3025			netif_reset_xps_queues_gt(dev, txq);
 3026#endif
 3027		}
 3028	} else {
 3029		dev->real_num_tx_queues = txq;
 3030	}
 3031
 
 3032	return 0;
 3033}
 3034EXPORT_SYMBOL(netif_set_real_num_tx_queues);
 3035
 3036#ifdef CONFIG_SYSFS
 3037/**
 3038 *	netif_set_real_num_rx_queues - set actual number of RX queues used
 3039 *	@dev: Network device
 3040 *	@rxq: Actual number of RX queues
 3041 *
 3042 *	This must be called either with the rtnl_lock held or before
 3043 *	registration of the net device.  Returns 0 on success, or a
 3044 *	negative error code.  If called before registration, it always
 3045 *	succeeds.
 3046 */
 3047int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
 3048{
 3049	int rc;
 3050
 3051	if (rxq < 1 || rxq > dev->num_rx_queues)
 3052		return -EINVAL;
 3053
 3054	if (dev->reg_state == NETREG_REGISTERED) {
 3055		ASSERT_RTNL();
 3056
 3057		rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
 3058						  rxq);
 3059		if (rc)
 3060			return rc;
 3061	}
 3062
 3063	dev->real_num_rx_queues = rxq;
 3064	return 0;
 3065}
 3066EXPORT_SYMBOL(netif_set_real_num_rx_queues);
 3067#endif
 3068
 3069/**
 3070 *	netif_set_real_num_queues - set actual number of RX and TX queues used
 3071 *	@dev: Network device
 3072 *	@txq: Actual number of TX queues
 3073 *	@rxq: Actual number of RX queues
 3074 *
 3075 *	Set the real number of both TX and RX queues.
 3076 *	Does nothing if the number of queues is already correct.
 3077 */
 3078int netif_set_real_num_queues(struct net_device *dev,
 3079			      unsigned int txq, unsigned int rxq)
 3080{
 3081	unsigned int old_rxq = dev->real_num_rx_queues;
 3082	int err;
 3083
 3084	if (txq < 1 || txq > dev->num_tx_queues ||
 3085	    rxq < 1 || rxq > dev->num_rx_queues)
 3086		return -EINVAL;
 3087
 3088	/* Start from increases, so the error path only does decreases -
 3089	 * decreases can't fail.
 3090	 */
 3091	if (rxq > dev->real_num_rx_queues) {
 3092		err = netif_set_real_num_rx_queues(dev, rxq);
 3093		if (err)
 3094			return err;
 3095	}
 3096	if (txq > dev->real_num_tx_queues) {
 3097		err = netif_set_real_num_tx_queues(dev, txq);
 3098		if (err)
 3099			goto undo_rx;
 3100	}
 3101	if (rxq < dev->real_num_rx_queues)
 3102		WARN_ON(netif_set_real_num_rx_queues(dev, rxq));
 3103	if (txq < dev->real_num_tx_queues)
 3104		WARN_ON(netif_set_real_num_tx_queues(dev, txq));
 3105
 3106	return 0;
 3107undo_rx:
 3108	WARN_ON(netif_set_real_num_rx_queues(dev, old_rxq));
 3109	return err;
 3110}
 3111EXPORT_SYMBOL(netif_set_real_num_queues);
 3112
 3113/**
 3114 * netif_set_tso_max_size() - set the max size of TSO frames supported
 3115 * @dev:	netdev to update
 3116 * @size:	max skb->len of a TSO frame
 3117 *
 3118 * Set the limit on the size of TSO super-frames the device can handle.
 3119 * Unless explicitly set the stack will assume the value of
 3120 * %GSO_LEGACY_MAX_SIZE.
 3121 */
 3122void netif_set_tso_max_size(struct net_device *dev, unsigned int size)
 3123{
 3124	dev->tso_max_size = min(GSO_MAX_SIZE, size);
 3125	if (size < READ_ONCE(dev->gso_max_size))
 3126		netif_set_gso_max_size(dev, size);
 3127	if (size < READ_ONCE(dev->gso_ipv4_max_size))
 3128		netif_set_gso_ipv4_max_size(dev, size);
 3129}
 3130EXPORT_SYMBOL(netif_set_tso_max_size);
 3131
 3132/**
 3133 * netif_set_tso_max_segs() - set the max number of segs supported for TSO
 3134 * @dev:	netdev to update
 3135 * @segs:	max number of TCP segments
 3136 *
 3137 * Set the limit on the number of TCP segments the device can generate from
 3138 * a single TSO super-frame.
 3139 * Unless explicitly set the stack will assume the value of %GSO_MAX_SEGS.
 3140 */
 3141void netif_set_tso_max_segs(struct net_device *dev, unsigned int segs)
 3142{
 3143	dev->tso_max_segs = segs;
 3144	if (segs < READ_ONCE(dev->gso_max_segs))
 3145		netif_set_gso_max_segs(dev, segs);
 3146}
 3147EXPORT_SYMBOL(netif_set_tso_max_segs);
 3148
 3149/**
 3150 * netif_inherit_tso_max() - copy all TSO limits from a lower device to an upper
 3151 * @to:		netdev to update
 3152 * @from:	netdev from which to copy the limits
 3153 */
 3154void netif_inherit_tso_max(struct net_device *to, const struct net_device *from)
 3155{
 3156	netif_set_tso_max_size(to, from->tso_max_size);
 3157	netif_set_tso_max_segs(to, from->tso_max_segs);
 3158}
 3159EXPORT_SYMBOL(netif_inherit_tso_max);
 3160
 3161/**
 3162 * netif_get_num_default_rss_queues - default number of RSS queues
 3163 *
 3164 * Default value is the number of physical cores if there are only 1 or 2, or
 3165 * divided by 2 if there are more.
 3166 */
 3167int netif_get_num_default_rss_queues(void)
 3168{
 3169	cpumask_var_t cpus;
 3170	int cpu, count = 0;
 3171
 3172	if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL)))
 3173		return 1;
 3174
 3175	cpumask_copy(cpus, cpu_online_mask);
 3176	for_each_cpu(cpu, cpus) {
 3177		++count;
 3178		cpumask_andnot(cpus, cpus, topology_sibling_cpumask(cpu));
 3179	}
 3180	free_cpumask_var(cpus);
 3181
 3182	return count > 2 ? DIV_ROUND_UP(count, 2) : count;
 3183}
 3184EXPORT_SYMBOL(netif_get_num_default_rss_queues);
 3185
 3186static void __netif_reschedule(struct Qdisc *q)
 3187{
 3188	struct softnet_data *sd;
 3189	unsigned long flags;
 3190
 3191	local_irq_save(flags);
 3192	sd = this_cpu_ptr(&softnet_data);
 3193	q->next_sched = NULL;
 3194	*sd->output_queue_tailp = q;
 3195	sd->output_queue_tailp = &q->next_sched;
 3196	raise_softirq_irqoff(NET_TX_SOFTIRQ);
 3197	local_irq_restore(flags);
 3198}
 3199
 3200void __netif_schedule(struct Qdisc *q)
 3201{
 3202	if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
 3203		__netif_reschedule(q);
 3204}
 3205EXPORT_SYMBOL(__netif_schedule);
 3206
 3207struct dev_kfree_skb_cb {
 3208	enum skb_drop_reason reason;
 3209};
 3210
 3211static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
 3212{
 3213	return (struct dev_kfree_skb_cb *)skb->cb;
 3214}
 3215
 3216void netif_schedule_queue(struct netdev_queue *txq)
 3217{
 3218	rcu_read_lock();
 3219	if (!netif_xmit_stopped(txq)) {
 3220		struct Qdisc *q = rcu_dereference(txq->qdisc);
 3221
 3222		__netif_schedule(q);
 3223	}
 3224	rcu_read_unlock();
 3225}
 3226EXPORT_SYMBOL(netif_schedule_queue);
 3227
 3228void netif_tx_wake_queue(struct netdev_queue *dev_queue)
 3229{
 3230	if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) {
 3231		struct Qdisc *q;
 3232
 3233		rcu_read_lock();
 3234		q = rcu_dereference(dev_queue->qdisc);
 3235		__netif_schedule(q);
 3236		rcu_read_unlock();
 3237	}
 3238}
 3239EXPORT_SYMBOL(netif_tx_wake_queue);
 3240
 3241void dev_kfree_skb_irq_reason(struct sk_buff *skb, enum skb_drop_reason reason)
 3242{
 3243	unsigned long flags;
 3244
 3245	if (unlikely(!skb))
 3246		return;
 3247
 3248	if (likely(refcount_read(&skb->users) == 1)) {
 3249		smp_rmb();
 3250		refcount_set(&skb->users, 0);
 3251	} else if (likely(!refcount_dec_and_test(&skb->users))) {
 3252		return;
 3253	}
 3254	get_kfree_skb_cb(skb)->reason = reason;
 3255	local_irq_save(flags);
 3256	skb->next = __this_cpu_read(softnet_data.completion_queue);
 3257	__this_cpu_write(softnet_data.completion_queue, skb);
 3258	raise_softirq_irqoff(NET_TX_SOFTIRQ);
 3259	local_irq_restore(flags);
 3260}
 3261EXPORT_SYMBOL(dev_kfree_skb_irq_reason);
 3262
 3263void dev_kfree_skb_any_reason(struct sk_buff *skb, enum skb_drop_reason reason)
 3264{
 3265	if (in_hardirq() || irqs_disabled())
 3266		dev_kfree_skb_irq_reason(skb, reason);
 3267	else
 3268		kfree_skb_reason(skb, reason);
 3269}
 3270EXPORT_SYMBOL(dev_kfree_skb_any_reason);
 3271
 3272
 3273/**
 3274 * netif_device_detach - mark device as removed
 3275 * @dev: network device
 3276 *
 3277 * Mark device as removed from system and therefore no longer available.
 3278 */
 3279void netif_device_detach(struct net_device *dev)
 3280{
 3281	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
 3282	    netif_running(dev)) {
 3283		netif_tx_stop_all_queues(dev);
 3284	}
 3285}
 3286EXPORT_SYMBOL(netif_device_detach);
 3287
 3288/**
 3289 * netif_device_attach - mark device as attached
 3290 * @dev: network device
 3291 *
 3292 * Mark device as attached from system and restart if needed.
 3293 */
 3294void netif_device_attach(struct net_device *dev)
 3295{
 3296	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
 3297	    netif_running(dev)) {
 3298		netif_tx_wake_all_queues(dev);
 3299		__netdev_watchdog_up(dev);
 3300	}
 3301}
 3302EXPORT_SYMBOL(netif_device_attach);
 3303
 3304/*
 3305 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
 3306 * to be used as a distribution range.
 3307 */
 3308static u16 skb_tx_hash(const struct net_device *dev,
 3309		       const struct net_device *sb_dev,
 3310		       struct sk_buff *skb)
 3311{
 3312	u32 hash;
 3313	u16 qoffset = 0;
 3314	u16 qcount = dev->real_num_tx_queues;
 3315
 3316	if (dev->num_tc) {
 3317		u8 tc = netdev_get_prio_tc_map(dev, skb->priority);
 3318
 3319		qoffset = sb_dev->tc_to_txq[tc].offset;
 3320		qcount = sb_dev->tc_to_txq[tc].count;
 3321		if (unlikely(!qcount)) {
 3322			net_warn_ratelimited("%s: invalid qcount, qoffset %u for tc %u\n",
 3323					     sb_dev->name, qoffset, tc);
 3324			qoffset = 0;
 3325			qcount = dev->real_num_tx_queues;
 3326		}
 3327	}
 3328
 3329	if (skb_rx_queue_recorded(skb)) {
 3330		DEBUG_NET_WARN_ON_ONCE(qcount == 0);
 3331		hash = skb_get_rx_queue(skb);
 3332		if (hash >= qoffset)
 3333			hash -= qoffset;
 3334		while (unlikely(hash >= qcount))
 3335			hash -= qcount;
 3336		return hash + qoffset;
 3337	}
 3338
 3339	return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset;
 3340}
 3341
 3342void skb_warn_bad_offload(const struct sk_buff *skb)
 3343{
 3344	static const netdev_features_t null_features;
 3345	struct net_device *dev = skb->dev;
 3346	const char *name = "";
 3347
 3348	if (!net_ratelimit())
 3349		return;
 3350
 3351	if (dev) {
 3352		if (dev->dev.parent)
 3353			name = dev_driver_string(dev->dev.parent);
 3354		else
 3355			name = netdev_name(dev);
 3356	}
 3357	skb_dump(KERN_WARNING, skb, false);
 3358	WARN(1, "%s: caps=(%pNF, %pNF)\n",
 3359	     name, dev ? &dev->features : &null_features,
 3360	     skb->sk ? &skb->sk->sk_route_caps : &null_features);
 3361}
 
 
 3362
 3363/*
 3364 * Invalidate hardware checksum when packet is to be mangled, and
 3365 * complete checksum manually on outgoing path.
 3366 */
 3367int skb_checksum_help(struct sk_buff *skb)
 3368{
 3369	__wsum csum;
 3370	int ret = 0, offset;
 3371
 3372	if (skb->ip_summed == CHECKSUM_COMPLETE)
 3373		goto out_set_summed;
 3374
 3375	if (unlikely(skb_is_gso(skb))) {
 3376		skb_warn_bad_offload(skb);
 3377		return -EINVAL;
 3378	}
 3379
 3380	if (!skb_frags_readable(skb)) {
 3381		return -EFAULT;
 3382	}
 3383
 3384	/* Before computing a checksum, we should make sure no frag could
 3385	 * be modified by an external entity : checksum could be wrong.
 3386	 */
 3387	if (skb_has_shared_frag(skb)) {
 3388		ret = __skb_linearize(skb);
 3389		if (ret)
 3390			goto out;
 3391	}
 3392
 3393	offset = skb_checksum_start_offset(skb);
 3394	ret = -EINVAL;
 3395	if (unlikely(offset >= skb_headlen(skb))) {
 3396		DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false);
 3397		WARN_ONCE(true, "offset (%d) >= skb_headlen() (%u)\n",
 3398			  offset, skb_headlen(skb));
 3399		goto out;
 3400	}
 3401	csum = skb_checksum(skb, offset, skb->len - offset, 0);
 3402
 3403	offset += skb->csum_offset;
 3404	if (unlikely(offset + sizeof(__sum16) > skb_headlen(skb))) {
 3405		DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false);
 3406		WARN_ONCE(true, "offset+2 (%zu) > skb_headlen() (%u)\n",
 3407			  offset + sizeof(__sum16), skb_headlen(skb));
 3408		goto out;
 
 
 3409	}
 3410	ret = skb_ensure_writable(skb, offset + sizeof(__sum16));
 3411	if (ret)
 3412		goto out;
 3413
 3414	*(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0;
 3415out_set_summed:
 3416	skb->ip_summed = CHECKSUM_NONE;
 3417out:
 3418	return ret;
 3419}
 3420EXPORT_SYMBOL(skb_checksum_help);
 3421
 3422int skb_crc32c_csum_help(struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
 3423{
 3424	__le32 crc32c_csum;
 3425	int ret = 0, offset, start;
 
 
 
 3426
 3427	if (skb->ip_summed != CHECKSUM_PARTIAL)
 3428		goto out;
 3429
 3430	if (unlikely(skb_is_gso(skb)))
 3431		goto out;
 3432
 3433	/* Before computing a checksum, we should make sure no frag could
 3434	 * be modified by an external entity : checksum could be wrong.
 3435	 */
 3436	if (unlikely(skb_has_shared_frag(skb))) {
 3437		ret = __skb_linearize(skb);
 3438		if (ret)
 3439			goto out;
 3440	}
 3441	start = skb_checksum_start_offset(skb);
 3442	offset = start + offsetof(struct sctphdr, checksum);
 3443	if (WARN_ON_ONCE(offset >= skb_headlen(skb))) {
 3444		ret = -EINVAL;
 3445		goto out;
 3446	}
 3447
 3448	ret = skb_ensure_writable(skb, offset + sizeof(__le32));
 3449	if (ret)
 3450		goto out;
 3451
 3452	crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start,
 3453						  skb->len - start, ~(__u32)0,
 3454						  crc32c_csum_stub));
 3455	*(__le32 *)(skb->data + offset) = crc32c_csum;
 3456	skb_reset_csum_not_inet(skb);
 3457out:
 3458	return ret;
 3459}
 3460EXPORT_SYMBOL(skb_crc32c_csum_help);
 3461
 3462__be16 skb_network_protocol(struct sk_buff *skb, int *depth)
 3463{
 3464	__be16 type = skb->protocol;
 3465
 3466	/* Tunnel gso handlers can set protocol to ethernet. */
 3467	if (type == htons(ETH_P_TEB)) {
 3468		struct ethhdr *eth;
 3469
 3470		if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
 3471			return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 3472
 3473		eth = (struct ethhdr *)skb->data;
 3474		type = eth->h_proto;
 
 
 
 
 
 
 
 
 
 
 
 
 
 3475	}
 
 3476
 3477	return vlan_get_protocol_and_depth(skb, type, depth);
 3478}
 3479
 
 
 
 3480
 3481/* Take action when hardware reception checksum errors are detected. */
 3482#ifdef CONFIG_BUG
 3483static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb)
 3484{
 3485	netdev_err(dev, "hw csum failure\n");
 3486	skb_dump(KERN_ERR, skb, true);
 3487	dump_stack();
 3488}
 3489
 3490void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb)
 3491{
 3492	DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb);
 
 
 
 
 3493}
 3494EXPORT_SYMBOL(netdev_rx_csum_fault);
 3495#endif
 3496
 3497/* XXX: check that highmem exists at all on the given machine. */
 
 
 
 
 3498static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
 3499{
 3500#ifdef CONFIG_HIGHMEM
 3501	int i;
 3502
 3503	if (!(dev->features & NETIF_F_HIGHDMA)) {
 3504		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 3505			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
 3506			struct page *page = skb_frag_page(frag);
 
 3507
 3508			if (page && PageHighMem(page))
 
 
 
 
 
 
 
 3509				return 1;
 3510		}
 3511	}
 3512#endif
 3513	return 0;
 3514}
 3515
 3516/* If MPLS offload request, verify we are testing hardware MPLS features
 3517 * instead of standard features for the netdev.
 3518 */
 3519#if IS_ENABLED(CONFIG_NET_MPLS_GSO)
 3520static netdev_features_t net_mpls_features(struct sk_buff *skb,
 3521					   netdev_features_t features,
 3522					   __be16 type)
 3523{
 3524	if (eth_p_mpls(type))
 3525		features &= skb->dev->mpls_features;
 3526
 3527	return features;
 3528}
 3529#else
 3530static netdev_features_t net_mpls_features(struct sk_buff *skb,
 3531					   netdev_features_t features,
 3532					   __be16 type)
 3533{
 3534	return features;
 3535}
 3536#endif
 3537
 3538static netdev_features_t harmonize_features(struct sk_buff *skb,
 3539	netdev_features_t features)
 3540{
 3541	__be16 type;
 3542
 3543	type = skb_network_protocol(skb, NULL);
 3544	features = net_mpls_features(skb, features, type);
 3545
 3546	if (skb->ip_summed != CHECKSUM_NONE &&
 3547	    !can_checksum_protocol(features, type)) {
 3548		features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
 3549	}
 3550	if (illegal_highdma(skb->dev, skb))
 3551		features &= ~NETIF_F_SG;
 3552
 3553	return features;
 
 
 3554}
 3555
 3556netdev_features_t passthru_features_check(struct sk_buff *skb,
 3557					  struct net_device *dev,
 3558					  netdev_features_t features)
 3559{
 3560	return features;
 3561}
 3562EXPORT_SYMBOL(passthru_features_check);
 3563
 3564static netdev_features_t dflt_features_check(struct sk_buff *skb,
 3565					     struct net_device *dev,
 3566					     netdev_features_t features)
 3567{
 3568	return vlan_features_check(skb, features);
 3569}
 3570
 3571static netdev_features_t gso_features_check(const struct sk_buff *skb,
 3572					    struct net_device *dev,
 3573					    netdev_features_t features)
 3574{
 3575	u16 gso_segs = skb_shinfo(skb)->gso_segs;
 3576
 3577	if (gso_segs > READ_ONCE(dev->gso_max_segs))
 3578		return features & ~NETIF_F_GSO_MASK;
 
 3579
 3580	if (unlikely(skb->len >= netif_get_gso_max_size(dev, skb)))
 3581		return features & ~NETIF_F_GSO_MASK;
 3582
 3583	if (!skb_shinfo(skb)->gso_type) {
 3584		skb_warn_bad_offload(skb);
 3585		return features & ~NETIF_F_GSO_MASK;
 3586	}
 3587
 3588	/* Support for GSO partial features requires software
 3589	 * intervention before we can actually process the packets
 3590	 * so we need to strip support for any partial features now
 3591	 * and we can pull them back in after we have partially
 3592	 * segmented the frame.
 3593	 */
 3594	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL))
 3595		features &= ~dev->gso_partial_features;
 3596
 3597	/* Make sure to clear the IPv4 ID mangling feature if the
 3598	 * IPv4 header has the potential to be fragmented.
 3599	 */
 3600	if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) {
 3601		struct iphdr *iph = skb->encapsulation ?
 3602				    inner_ip_hdr(skb) : ip_hdr(skb);
 
 
 3603
 3604		if (!(iph->frag_off & htons(IP_DF)))
 3605			features &= ~NETIF_F_TSO_MANGLEID;
 
 
 
 
 
 3606	}
 3607
 3608	return features;
 3609}
 3610
 3611netdev_features_t netif_skb_features(struct sk_buff *skb)
 3612{
 3613	struct net_device *dev = skb->dev;
 3614	netdev_features_t features = dev->features;
 3615
 3616	if (skb_is_gso(skb))
 3617		features = gso_features_check(skb, dev, features);
 3618
 3619	/* If encapsulation offload request, verify we are testing
 3620	 * hardware encapsulation features instead of standard
 3621	 * features for the netdev
 3622	 */
 3623	if (skb->encapsulation)
 3624		features &= dev->hw_enc_features;
 3625
 3626	if (skb_vlan_tagged(skb))
 3627		features = netdev_intersect_features(features,
 3628						     dev->vlan_features |
 3629						     NETIF_F_HW_VLAN_CTAG_TX |
 3630						     NETIF_F_HW_VLAN_STAG_TX);
 3631
 3632	if (dev->netdev_ops->ndo_features_check)
 3633		features &= dev->netdev_ops->ndo_features_check(skb, dev,
 3634								features);
 3635	else
 3636		features &= dflt_features_check(skb, dev, features);
 3637
 3638	return harmonize_features(skb, features);
 3639}
 3640EXPORT_SYMBOL(netif_skb_features);
 3641
 3642static int xmit_one(struct sk_buff *skb, struct net_device *dev,
 3643		    struct netdev_queue *txq, bool more)
 3644{
 3645	unsigned int len;
 3646	int rc;
 3647
 3648	if (dev_nit_active(dev))
 3649		dev_queue_xmit_nit(skb, dev);
 3650
 3651	len = skb->len;
 3652	trace_net_dev_start_xmit(skb, dev);
 3653	rc = netdev_start_xmit(skb, dev, txq, more);
 3654	trace_net_dev_xmit(skb, rc, dev, len);
 3655
 3656	return rc;
 3657}
 3658
 3659struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
 3660				    struct netdev_queue *txq, int *ret)
 3661{
 3662	struct sk_buff *skb = first;
 3663	int rc = NETDEV_TX_OK;
 3664
 3665	while (skb) {
 3666		struct sk_buff *next = skb->next;
 
 
 
 
 3667
 3668		skb_mark_not_on_list(skb);
 3669		rc = xmit_one(skb, dev, txq, next != NULL);
 3670		if (unlikely(!dev_xmit_complete(rc))) {
 3671			skb->next = next;
 3672			goto out;
 3673		}
 3674
 3675		skb = next;
 3676		if (netif_tx_queue_stopped(txq) && skb) {
 3677			rc = NETDEV_TX_BUSY;
 3678			break;
 3679		}
 
 3680	}
 3681
 3682out:
 3683	*ret = rc;
 3684	return skb;
 3685}
 
 3686
 3687static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
 3688					  netdev_features_t features)
 3689{
 3690	if (skb_vlan_tag_present(skb) &&
 3691	    !vlan_hw_offload_capable(features, skb->vlan_proto))
 3692		skb = __vlan_hwaccel_push_inside(skb);
 3693	return skb;
 
 
 
 
 
 
 
 
 3694}
 3695
 3696int skb_csum_hwoffload_help(struct sk_buff *skb,
 3697			    const netdev_features_t features)
 3698{
 3699	if (unlikely(skb_csum_is_sctp(skb)))
 3700		return !!(features & NETIF_F_SCTP_CRC) ? 0 :
 3701			skb_crc32c_csum_help(skb);
 3702
 3703	if (features & NETIF_F_HW_CSUM)
 3704		return 0;
 3705
 3706	if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) {
 3707		if (vlan_get_protocol(skb) == htons(ETH_P_IPV6) &&
 3708		    skb_network_header_len(skb) != sizeof(struct ipv6hdr) &&
 3709		    !ipv6_has_hopopt_jumbo(skb))
 3710			goto sw_checksum;
 3711
 3712		switch (skb->csum_offset) {
 3713		case offsetof(struct tcphdr, check):
 3714		case offsetof(struct udphdr, check):
 3715			return 0;
 3716		}
 3717	}
 3718
 3719sw_checksum:
 3720	return skb_checksum_help(skb);
 3721}
 3722EXPORT_SYMBOL(skb_csum_hwoffload_help);
 3723
 3724static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again)
 3725{
 3726	netdev_features_t features;
 3727
 3728	features = netif_skb_features(skb);
 3729	skb = validate_xmit_vlan(skb, features);
 3730	if (unlikely(!skb))
 3731		goto out_null;
 3732
 3733	skb = sk_validate_xmit_skb(skb, dev);
 3734	if (unlikely(!skb))
 3735		goto out_null;
 3736
 3737	if (netif_needs_gso(skb, features)) {
 3738		struct sk_buff *segs;
 
 
 
 3739
 3740		segs = skb_gso_segment(skb, features);
 3741		if (IS_ERR(segs)) {
 3742			goto out_kfree_skb;
 3743		} else if (segs) {
 3744			consume_skb(skb);
 3745			skb = segs;
 3746		}
 3747	} else {
 3748		if (skb_needs_linearize(skb, features) &&
 3749		    __skb_linearize(skb))
 3750			goto out_kfree_skb;
 3751
 3752		/* If packet is not checksummed and device does not
 3753		 * support checksumming for this protocol, complete
 3754		 * checksumming here.
 3755		 */
 3756		if (skb->ip_summed == CHECKSUM_PARTIAL) {
 3757			if (skb->encapsulation)
 3758				skb_set_inner_transport_header(skb,
 3759							       skb_checksum_start_offset(skb));
 3760			else
 3761				skb_set_transport_header(skb,
 3762							 skb_checksum_start_offset(skb));
 3763			if (skb_csum_hwoffload_help(skb, features))
 3764				goto out_kfree_skb;
 
 
 
 
 
 
 
 
 
 
 
 
 3765		}
 
 
 
 
 
 
 
 3766	}
 3767
 3768	skb = validate_xmit_xfrm(skb, features, again);
 
 
 
 
 
 3769
 3770	return skb;
 
 
 
 
 
 3771
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 3772out_kfree_skb:
 3773	kfree_skb(skb);
 3774out_null:
 3775	dev_core_stats_tx_dropped_inc(dev);
 3776	return NULL;
 3777}
 3778
 3779struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again)
 
 
 
 
 
 
 
 3780{
 3781	struct sk_buff *next, *head = NULL, *tail;
 
 
 3782
 3783	for (; skb != NULL; skb = next) {
 3784		next = skb->next;
 3785		skb_mark_not_on_list(skb);
 
 
 
 
 
 
 
 
 
 3786
 3787		/* in case skb won't be segmented, point to itself */
 3788		skb->prev = skb;
 
 
 
 3789
 3790		skb = validate_xmit_skb(skb, dev, again);
 3791		if (!skb)
 3792			continue;
 3793
 3794		if (!head)
 3795			head = skb;
 3796		else
 3797			tail->next = skb;
 3798		/* If skb was segmented, skb->prev points to
 3799		 * the last segment. If not, it still contains skb.
 3800		 */
 3801		tail = skb->prev;
 
 3802	}
 3803	return head;
 3804}
 3805EXPORT_SYMBOL_GPL(validate_xmit_skb_list);
 3806
 3807static void qdisc_pkt_len_init(struct sk_buff *skb)
 3808{
 3809	const struct skb_shared_info *shinfo = skb_shinfo(skb);
 3810
 3811	qdisc_skb_cb(skb)->pkt_len = skb->len;
 3812
 3813	/* To get more precise estimation of bytes sent on wire,
 3814	 * we add to pkt_len the headers size of all segments
 3815	 */
 3816	if (shinfo->gso_size && skb_transport_header_was_set(skb)) {
 3817		u16 gso_segs = shinfo->gso_segs;
 3818		unsigned int hdr_len;
 3819
 3820		/* mac layer + network layer */
 3821		hdr_len = skb_transport_offset(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 3822
 3823		/* + transport layer */
 3824		if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) {
 3825			const struct tcphdr *th;
 3826			struct tcphdr _tcphdr;
 
 3827
 3828			th = skb_header_pointer(skb, hdr_len,
 3829						sizeof(_tcphdr), &_tcphdr);
 3830			if (likely(th))
 3831				hdr_len += __tcp_hdrlen(th);
 3832		} else if (shinfo->gso_type & SKB_GSO_UDP_L4) {
 3833			struct udphdr _udphdr;
 3834
 3835			if (skb_header_pointer(skb, hdr_len,
 3836					       sizeof(_udphdr), &_udphdr))
 3837				hdr_len += sizeof(struct udphdr);
 3838		}
 
 
 
 
 3839
 3840		if (unlikely(shinfo->gso_type & SKB_GSO_DODGY)) {
 3841			int payload = skb->len - hdr_len;
 
 
 
 
 
 
 
 
 
 3842
 3843			/* Malicious packet. */
 3844			if (payload <= 0)
 3845				return;
 3846			gso_segs = DIV_ROUND_UP(payload, shinfo->gso_size);
 3847		}
 3848		qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
 3849	}
 3850}
 3851
 3852static int dev_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *q,
 3853			     struct sk_buff **to_free,
 3854			     struct netdev_queue *txq)
 3855{
 3856	int rc;
 3857
 3858	rc = q->enqueue(skb, q, to_free) & NET_XMIT_MASK;
 3859	if (rc == NET_XMIT_SUCCESS)
 3860		trace_qdisc_enqueue(q, txq, skb);
 3861	return rc;
 3862}
 3863
 3864static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
 3865				 struct net_device *dev,
 3866				 struct netdev_queue *txq)
 3867{
 3868	spinlock_t *root_lock = qdisc_lock(q);
 3869	struct sk_buff *to_free = NULL;
 3870	bool contended;
 3871	int rc;
 3872
 
 3873	qdisc_calculate_pkt_len(skb, q);
 3874
 3875	tcf_set_drop_reason(skb, SKB_DROP_REASON_QDISC_DROP);
 3876
 3877	if (q->flags & TCQ_F_NOLOCK) {
 3878		if (q->flags & TCQ_F_CAN_BYPASS && nolock_qdisc_is_empty(q) &&
 3879		    qdisc_run_begin(q)) {
 3880			/* Retest nolock_qdisc_is_empty() within the protection
 3881			 * of q->seqlock to protect from racing with requeuing.
 3882			 */
 3883			if (unlikely(!nolock_qdisc_is_empty(q))) {
 3884				rc = dev_qdisc_enqueue(skb, q, &to_free, txq);
 3885				__qdisc_run(q);
 3886				qdisc_run_end(q);
 3887
 3888				goto no_lock_out;
 3889			}
 3890
 3891			qdisc_bstats_cpu_update(q, skb);
 3892			if (sch_direct_xmit(skb, q, dev, txq, NULL, true) &&
 3893			    !nolock_qdisc_is_empty(q))
 3894				__qdisc_run(q);
 3895
 3896			qdisc_run_end(q);
 3897			return NET_XMIT_SUCCESS;
 3898		}
 3899
 3900		rc = dev_qdisc_enqueue(skb, q, &to_free, txq);
 3901		qdisc_run(q);
 3902
 3903no_lock_out:
 3904		if (unlikely(to_free))
 3905			kfree_skb_list_reason(to_free,
 3906					      tcf_get_drop_reason(to_free));
 3907		return rc;
 3908	}
 3909
 3910	if (unlikely(READ_ONCE(q->owner) == smp_processor_id())) {
 3911		kfree_skb_reason(skb, SKB_DROP_REASON_TC_RECLASSIFY_LOOP);
 3912		return NET_XMIT_DROP;
 3913	}
 3914	/*
 3915	 * Heuristic to force contended enqueues to serialize on a
 3916	 * separate lock before trying to get qdisc main lock.
 3917	 * This permits qdisc->running owner to get the lock more
 3918	 * often and dequeue packets faster.
 3919	 * On PREEMPT_RT it is possible to preempt the qdisc owner during xmit
 3920	 * and then other tasks will only enqueue packets. The packets will be
 3921	 * sent after the qdisc owner is scheduled again. To prevent this
 3922	 * scenario the task always serialize on the lock.
 3923	 */
 3924	contended = qdisc_is_running(q) || IS_ENABLED(CONFIG_PREEMPT_RT);
 3925	if (unlikely(contended))
 3926		spin_lock(&q->busylock);
 3927
 3928	spin_lock(root_lock);
 3929	if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
 3930		__qdisc_drop(skb, &to_free);
 3931		rc = NET_XMIT_DROP;
 3932	} else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
 3933		   qdisc_run_begin(q)) {
 3934		/*
 3935		 * This is a work-conserving queue; there are no old skbs
 3936		 * waiting to be sent out; and the qdisc is not running -
 3937		 * xmit the skb directly.
 3938		 */
 
 
 3939
 3940		qdisc_bstats_update(q, skb);
 3941
 3942		if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) {
 3943			if (unlikely(contended)) {
 3944				spin_unlock(&q->busylock);
 3945				contended = false;
 3946			}
 3947			__qdisc_run(q);
 3948		}
 
 3949
 3950		qdisc_run_end(q);
 3951		rc = NET_XMIT_SUCCESS;
 3952	} else {
 3953		WRITE_ONCE(q->owner, smp_processor_id());
 3954		rc = dev_qdisc_enqueue(skb, q, &to_free, txq);
 3955		WRITE_ONCE(q->owner, -1);
 3956		if (qdisc_run_begin(q)) {
 3957			if (unlikely(contended)) {
 3958				spin_unlock(&q->busylock);
 3959				contended = false;
 3960			}
 3961			__qdisc_run(q);
 3962			qdisc_run_end(q);
 3963		}
 3964	}
 3965	spin_unlock(root_lock);
 3966	if (unlikely(to_free))
 3967		kfree_skb_list_reason(to_free,
 3968				      tcf_get_drop_reason(to_free));
 3969	if (unlikely(contended))
 3970		spin_unlock(&q->busylock);
 3971	return rc;
 3972}
 3973
 3974#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
 3975static void skb_update_prio(struct sk_buff *skb)
 3976{
 3977	const struct netprio_map *map;
 3978	const struct sock *sk;
 3979	unsigned int prioidx;
 3980
 3981	if (skb->priority)
 3982		return;
 3983	map = rcu_dereference_bh(skb->dev->priomap);
 3984	if (!map)
 3985		return;
 3986	sk = skb_to_full_sk(skb);
 3987	if (!sk)
 3988		return;
 3989
 3990	prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data);
 3991
 3992	if (prioidx < map->priomap_len)
 3993		skb->priority = map->priomap[prioidx];
 3994}
 3995#else
 3996#define skb_update_prio(skb)
 3997#endif
 3998
 3999/**
 4000 *	dev_loopback_xmit - loop back @skb
 4001 *	@net: network namespace this loopback is happening in
 4002 *	@sk:  sk needed to be a netfilter okfn
 4003 *	@skb: buffer to transmit
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 4004 */
 4005int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
 4006{
 4007	skb_reset_mac_header(skb);
 4008	__skb_pull(skb, skb_network_offset(skb));
 4009	skb->pkt_type = PACKET_LOOPBACK;
 4010	if (skb->ip_summed == CHECKSUM_NONE)
 4011		skb->ip_summed = CHECKSUM_UNNECESSARY;
 4012	DEBUG_NET_WARN_ON_ONCE(!skb_dst(skb));
 4013	skb_dst_force(skb);
 4014	netif_rx(skb);
 4015	return 0;
 4016}
 4017EXPORT_SYMBOL(dev_loopback_xmit);
 4018
 4019#ifdef CONFIG_NET_EGRESS
 4020static struct netdev_queue *
 4021netdev_tx_queue_mapping(struct net_device *dev, struct sk_buff *skb)
 4022{
 4023	int qm = skb_get_queue_mapping(skb);
 4024
 4025	return netdev_get_tx_queue(dev, netdev_cap_txqueue(dev, qm));
 4026}
 4027
 4028#ifndef CONFIG_PREEMPT_RT
 4029static bool netdev_xmit_txqueue_skipped(void)
 4030{
 4031	return __this_cpu_read(softnet_data.xmit.skip_txqueue);
 4032}
 4033
 4034void netdev_xmit_skip_txqueue(bool skip)
 4035{
 4036	__this_cpu_write(softnet_data.xmit.skip_txqueue, skip);
 4037}
 4038EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue);
 4039
 4040#else
 4041static bool netdev_xmit_txqueue_skipped(void)
 4042{
 4043	return current->net_xmit.skip_txqueue;
 4044}
 4045
 4046void netdev_xmit_skip_txqueue(bool skip)
 4047{
 4048	current->net_xmit.skip_txqueue = skip;
 4049}
 4050EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue);
 4051#endif
 4052#endif /* CONFIG_NET_EGRESS */
 4053
 4054#ifdef CONFIG_NET_XGRESS
 4055static int tc_run(struct tcx_entry *entry, struct sk_buff *skb,
 4056		  enum skb_drop_reason *drop_reason)
 4057{
 4058	int ret = TC_ACT_UNSPEC;
 4059#ifdef CONFIG_NET_CLS_ACT
 4060	struct mini_Qdisc *miniq = rcu_dereference_bh(entry->miniq);
 4061	struct tcf_result res;
 4062
 4063	if (!miniq)
 4064		return ret;
 4065
 4066	/* Global bypass */
 4067	if (!static_branch_likely(&tcf_sw_enabled_key))
 4068		return ret;
 4069
 4070	/* Block-wise bypass */
 4071	if (tcf_block_bypass_sw(miniq->block))
 4072		return ret;
 4073
 4074	tc_skb_cb(skb)->mru = 0;
 4075	tc_skb_cb(skb)->post_ct = false;
 4076	tcf_set_drop_reason(skb, *drop_reason);
 4077
 4078	mini_qdisc_bstats_cpu_update(miniq, skb);
 4079	ret = tcf_classify(skb, miniq->block, miniq->filter_list, &res, false);
 4080	/* Only tcf related quirks below. */
 4081	switch (ret) {
 4082	case TC_ACT_SHOT:
 4083		*drop_reason = tcf_get_drop_reason(skb);
 4084		mini_qdisc_qstats_cpu_drop(miniq);
 4085		break;
 4086	case TC_ACT_OK:
 4087	case TC_ACT_RECLASSIFY:
 4088		skb->tc_index = TC_H_MIN(res.classid);
 4089		break;
 4090	}
 4091#endif /* CONFIG_NET_CLS_ACT */
 4092	return ret;
 4093}
 4094
 4095static DEFINE_STATIC_KEY_FALSE(tcx_needed_key);
 4096
 4097void tcx_inc(void)
 4098{
 4099	static_branch_inc(&tcx_needed_key);
 4100}
 4101
 4102void tcx_dec(void)
 4103{
 4104	static_branch_dec(&tcx_needed_key);
 4105}
 4106
 4107static __always_inline enum tcx_action_base
 4108tcx_run(const struct bpf_mprog_entry *entry, struct sk_buff *skb,
 4109	const bool needs_mac)
 4110{
 4111	const struct bpf_mprog_fp *fp;
 4112	const struct bpf_prog *prog;
 4113	int ret = TCX_NEXT;
 4114
 4115	if (needs_mac)
 4116		__skb_push(skb, skb->mac_len);
 4117	bpf_mprog_foreach_prog(entry, fp, prog) {
 4118		bpf_compute_data_pointers(skb);
 4119		ret = bpf_prog_run(prog, skb);
 4120		if (ret != TCX_NEXT)
 4121			break;
 4122	}
 4123	if (needs_mac)
 4124		__skb_pull(skb, skb->mac_len);
 4125	return tcx_action_code(skb, ret);
 4126}
 4127
 4128static __always_inline struct sk_buff *
 4129sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
 4130		   struct net_device *orig_dev, bool *another)
 4131{
 4132	struct bpf_mprog_entry *entry = rcu_dereference_bh(skb->dev->tcx_ingress);
 4133	enum skb_drop_reason drop_reason = SKB_DROP_REASON_TC_INGRESS;
 4134	struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx;
 4135	int sch_ret;
 4136
 4137	if (!entry)
 4138		return skb;
 4139
 4140	bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx);
 4141	if (*pt_prev) {
 4142		*ret = deliver_skb(skb, *pt_prev, orig_dev);
 4143		*pt_prev = NULL;
 4144	}
 4145
 4146	qdisc_skb_cb(skb)->pkt_len = skb->len;
 4147	tcx_set_ingress(skb, true);
 4148
 4149	if (static_branch_unlikely(&tcx_needed_key)) {
 4150		sch_ret = tcx_run(entry, skb, true);
 4151		if (sch_ret != TC_ACT_UNSPEC)
 4152			goto ingress_verdict;
 4153	}
 4154	sch_ret = tc_run(tcx_entry(entry), skb, &drop_reason);
 4155ingress_verdict:
 4156	switch (sch_ret) {
 4157	case TC_ACT_REDIRECT:
 4158		/* skb_mac_header check was done by BPF, so we can safely
 4159		 * push the L2 header back before redirecting to another
 4160		 * netdev.
 4161		 */
 4162		__skb_push(skb, skb->mac_len);
 4163		if (skb_do_redirect(skb) == -EAGAIN) {
 4164			__skb_pull(skb, skb->mac_len);
 4165			*another = true;
 4166			break;
 4167		}
 4168		*ret = NET_RX_SUCCESS;
 4169		bpf_net_ctx_clear(bpf_net_ctx);
 4170		return NULL;
 4171	case TC_ACT_SHOT:
 4172		kfree_skb_reason(skb, drop_reason);
 4173		*ret = NET_RX_DROP;
 4174		bpf_net_ctx_clear(bpf_net_ctx);
 4175		return NULL;
 4176	/* used by tc_run */
 4177	case TC_ACT_STOLEN:
 4178	case TC_ACT_QUEUED:
 4179	case TC_ACT_TRAP:
 4180		consume_skb(skb);
 4181		fallthrough;
 4182	case TC_ACT_CONSUMED:
 4183		*ret = NET_RX_SUCCESS;
 4184		bpf_net_ctx_clear(bpf_net_ctx);
 4185		return NULL;
 4186	}
 4187	bpf_net_ctx_clear(bpf_net_ctx);
 4188
 4189	return skb;
 4190}
 4191
 4192static __always_inline struct sk_buff *
 4193sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
 4194{
 4195	struct bpf_mprog_entry *entry = rcu_dereference_bh(dev->tcx_egress);
 4196	enum skb_drop_reason drop_reason = SKB_DROP_REASON_TC_EGRESS;
 4197	struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx;
 4198	int sch_ret;
 4199
 4200	if (!entry)
 4201		return skb;
 4202
 4203	bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx);
 4204
 4205	/* qdisc_skb_cb(skb)->pkt_len & tcx_set_ingress() was
 4206	 * already set by the caller.
 4207	 */
 4208	if (static_branch_unlikely(&tcx_needed_key)) {
 4209		sch_ret = tcx_run(entry, skb, false);
 4210		if (sch_ret != TC_ACT_UNSPEC)
 4211			goto egress_verdict;
 4212	}
 4213	sch_ret = tc_run(tcx_entry(entry), skb, &drop_reason);
 4214egress_verdict:
 4215	switch (sch_ret) {
 4216	case TC_ACT_REDIRECT:
 4217		/* No need to push/pop skb's mac_header here on egress! */
 4218		skb_do_redirect(skb);
 4219		*ret = NET_XMIT_SUCCESS;
 4220		bpf_net_ctx_clear(bpf_net_ctx);
 4221		return NULL;
 4222	case TC_ACT_SHOT:
 4223		kfree_skb_reason(skb, drop_reason);
 4224		*ret = NET_XMIT_DROP;
 4225		bpf_net_ctx_clear(bpf_net_ctx);
 4226		return NULL;
 4227	/* used by tc_run */
 4228	case TC_ACT_STOLEN:
 4229	case TC_ACT_QUEUED:
 4230	case TC_ACT_TRAP:
 4231		consume_skb(skb);
 4232		fallthrough;
 4233	case TC_ACT_CONSUMED:
 4234		*ret = NET_XMIT_SUCCESS;
 4235		bpf_net_ctx_clear(bpf_net_ctx);
 4236		return NULL;
 4237	}
 4238	bpf_net_ctx_clear(bpf_net_ctx);
 4239
 4240	return skb;
 4241}
 4242#else
 4243static __always_inline struct sk_buff *
 4244sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
 4245		   struct net_device *orig_dev, bool *another)
 4246{
 4247	return skb;
 4248}
 4249
 4250static __always_inline struct sk_buff *
 4251sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
 4252{
 4253	return skb;
 4254}
 4255#endif /* CONFIG_NET_XGRESS */
 4256
 4257#ifdef CONFIG_XPS
 4258static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb,
 4259			       struct xps_dev_maps *dev_maps, unsigned int tci)
 4260{
 4261	int tc = netdev_get_prio_tc_map(dev, skb->priority);
 4262	struct xps_map *map;
 4263	int queue_index = -1;
 4264
 4265	if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids)
 4266		return queue_index;
 4267
 4268	tci *= dev_maps->num_tc;
 4269	tci += tc;
 4270
 4271	map = rcu_dereference(dev_maps->attr_map[tci]);
 4272	if (map) {
 4273		if (map->len == 1)
 4274			queue_index = map->queues[0];
 4275		else
 4276			queue_index = map->queues[reciprocal_scale(
 4277						skb_get_hash(skb), map->len)];
 4278		if (unlikely(queue_index >= dev->real_num_tx_queues))
 4279			queue_index = -1;
 4280	}
 4281	return queue_index;
 4282}
 4283#endif
 4284
 4285static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev,
 4286			 struct sk_buff *skb)
 4287{
 4288#ifdef CONFIG_XPS
 4289	struct xps_dev_maps *dev_maps;
 4290	struct sock *sk = skb->sk;
 4291	int queue_index = -1;
 4292
 4293	if (!static_key_false(&xps_needed))
 4294		return -1;
 4295
 4296	rcu_read_lock();
 4297	if (!static_key_false(&xps_rxqs_needed))
 4298		goto get_cpus_map;
 4299
 4300	dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_RXQS]);
 4301	if (dev_maps) {
 4302		int tci = sk_rx_queue_get(sk);
 4303
 4304		if (tci >= 0)
 4305			queue_index = __get_xps_queue_idx(dev, skb, dev_maps,
 4306							  tci);
 4307	}
 4308
 4309get_cpus_map:
 4310	if (queue_index < 0) {
 4311		dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_CPUS]);
 4312		if (dev_maps) {
 4313			unsigned int tci = skb->sender_cpu - 1;
 4314
 4315			queue_index = __get_xps_queue_idx(dev, skb, dev_maps,
 4316							  tci);
 4317		}
 4318	}
 4319	rcu_read_unlock();
 4320
 4321	return queue_index;
 4322#else
 4323	return -1;
 4324#endif
 4325}
 4326
 4327u16 dev_pick_tx_zero(struct net_device *dev, struct sk_buff *skb,
 4328		     struct net_device *sb_dev)
 4329{
 4330	return 0;
 4331}
 4332EXPORT_SYMBOL(dev_pick_tx_zero);
 4333
 4334u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb,
 4335		     struct net_device *sb_dev)
 4336{
 4337	struct sock *sk = skb->sk;
 4338	int queue_index = sk_tx_queue_get(sk);
 4339
 4340	sb_dev = sb_dev ? : dev;
 4341
 4342	if (queue_index < 0 || skb->ooo_okay ||
 4343	    queue_index >= dev->real_num_tx_queues) {
 4344		int new_index = get_xps_queue(dev, sb_dev, skb);
 4345
 4346		if (new_index < 0)
 4347			new_index = skb_tx_hash(dev, sb_dev, skb);
 4348
 4349		if (queue_index != new_index && sk &&
 4350		    sk_fullsock(sk) &&
 4351		    rcu_access_pointer(sk->sk_dst_cache))
 4352			sk_tx_queue_set(sk, new_index);
 4353
 4354		queue_index = new_index;
 4355	}
 4356
 4357	return queue_index;
 4358}
 4359EXPORT_SYMBOL(netdev_pick_tx);
 4360
 4361struct netdev_queue *netdev_core_pick_tx(struct net_device *dev,
 4362					 struct sk_buff *skb,
 4363					 struct net_device *sb_dev)
 4364{
 4365	int queue_index = 0;
 4366
 4367#ifdef CONFIG_XPS
 4368	u32 sender_cpu = skb->sender_cpu - 1;
 4369
 4370	if (sender_cpu >= (u32)NR_CPUS)
 4371		skb->sender_cpu = raw_smp_processor_id() + 1;
 4372#endif
 4373
 4374	if (dev->real_num_tx_queues != 1) {
 4375		const struct net_device_ops *ops = dev->netdev_ops;
 4376
 4377		if (ops->ndo_select_queue)
 4378			queue_index = ops->ndo_select_queue(dev, skb, sb_dev);
 4379		else
 4380			queue_index = netdev_pick_tx(dev, skb, sb_dev);
 4381
 4382		queue_index = netdev_cap_txqueue(dev, queue_index);
 4383	}
 4384
 4385	skb_set_queue_mapping(skb, queue_index);
 4386	return netdev_get_tx_queue(dev, queue_index);
 4387}
 4388
 4389/**
 4390 * __dev_queue_xmit() - transmit a buffer
 4391 * @skb:	buffer to transmit
 4392 * @sb_dev:	suboordinate device used for L2 forwarding offload
 4393 *
 4394 * Queue a buffer for transmission to a network device. The caller must
 4395 * have set the device and priority and built the buffer before calling
 4396 * this function. The function can be called from an interrupt.
 4397 *
 4398 * When calling this method, interrupts MUST be enabled. This is because
 4399 * the BH enable code must have IRQs enabled so that it will not deadlock.
 4400 *
 4401 * Regardless of the return value, the skb is consumed, so it is currently
 4402 * difficult to retry a send to this method. (You can bump the ref count
 4403 * before sending to hold a reference for retry if you are careful.)
 4404 *
 4405 * Return:
 4406 * * 0				- buffer successfully transmitted
 4407 * * positive qdisc return code	- NET_XMIT_DROP etc.
 4408 * * negative errno		- other errors
 4409 */
 4410int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev)
 4411{
 4412	struct net_device *dev = skb->dev;
 4413	struct netdev_queue *txq = NULL;
 4414	struct Qdisc *q;
 4415	int rc = -ENOMEM;
 4416	bool again = false;
 4417
 4418	skb_reset_mac_header(skb);
 4419	skb_assert_len(skb);
 4420
 4421	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
 4422		__skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED);
 4423
 4424	/* Disable soft irqs for various locks below. Also
 4425	 * stops preemption for RCU.
 4426	 */
 4427	rcu_read_lock_bh();
 4428
 4429	skb_update_prio(skb);
 4430
 4431	qdisc_pkt_len_init(skb);
 4432	tcx_set_ingress(skb, false);
 4433#ifdef CONFIG_NET_EGRESS
 4434	if (static_branch_unlikely(&egress_needed_key)) {
 4435		if (nf_hook_egress_active()) {
 4436			skb = nf_hook_egress(skb, &rc, dev);
 4437			if (!skb)
 4438				goto out;
 4439		}
 4440
 4441		netdev_xmit_skip_txqueue(false);
 4442
 4443		nf_skip_egress(skb, true);
 4444		skb = sch_handle_egress(skb, &rc, dev);
 4445		if (!skb)
 4446			goto out;
 4447		nf_skip_egress(skb, false);
 4448
 4449		if (netdev_xmit_txqueue_skipped())
 4450			txq = netdev_tx_queue_mapping(dev, skb);
 4451	}
 4452#endif
 4453	/* If device/qdisc don't need skb->dst, release it right now while
 4454	 * its hot in this cpu cache.
 4455	 */
 4456	if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
 4457		skb_dst_drop(skb);
 4458	else
 4459		skb_dst_force(skb);
 4460
 4461	if (!txq)
 4462		txq = netdev_core_pick_tx(dev, skb, sb_dev);
 4463
 4464	q = rcu_dereference_bh(txq->qdisc);
 4465
 
 
 
 4466	trace_net_dev_queue(skb);
 4467	if (q->enqueue) {
 4468		rc = __dev_xmit_skb(skb, q, dev, txq);
 4469		goto out;
 4470	}
 4471
 4472	/* The device has no queue. Common case for software devices:
 4473	 * loopback, all the sorts of tunnels...
 4474
 4475	 * Really, it is unlikely that netif_tx_lock protection is necessary
 4476	 * here.  (f.e. loopback and IP tunnels are clean ignoring statistics
 4477	 * counters.)
 4478	 * However, it is possible, that they rely on protection
 4479	 * made by us here.
 4480
 4481	 * Check this and shot the lock. It is not prone from deadlocks.
 4482	 *Either shot noqueue qdisc, it is even simpler 8)
 4483	 */
 4484	if (dev->flags & IFF_UP) {
 4485		int cpu = smp_processor_id(); /* ok because BHs are off */
 4486
 4487		/* Other cpus might concurrently change txq->xmit_lock_owner
 4488		 * to -1 or to their cpu id, but not to our id.
 4489		 */
 4490		if (READ_ONCE(txq->xmit_lock_owner) != cpu) {
 4491			if (dev_xmit_recursion())
 4492				goto recursion_alert;
 4493
 4494			skb = validate_xmit_skb(skb, dev, &again);
 4495			if (!skb)
 4496				goto out;
 4497
 4498			HARD_TX_LOCK(dev, txq, cpu);
 4499
 4500			if (!netif_xmit_stopped(txq)) {
 4501				dev_xmit_recursion_inc();
 4502				skb = dev_hard_start_xmit(skb, dev, txq, &rc);
 4503				dev_xmit_recursion_dec();
 4504				if (dev_xmit_complete(rc)) {
 4505					HARD_TX_UNLOCK(dev, txq);
 4506					goto out;
 4507				}
 4508			}
 4509			HARD_TX_UNLOCK(dev, txq);
 4510			net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
 4511					     dev->name);
 
 4512		} else {
 4513			/* Recursion is detected! It is possible,
 4514			 * unfortunately
 4515			 */
 4516recursion_alert:
 4517			net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
 4518					     dev->name);
 
 4519		}
 4520	}
 4521
 4522	rc = -ENETDOWN;
 4523	rcu_read_unlock_bh();
 4524
 4525	dev_core_stats_tx_dropped_inc(dev);
 4526	kfree_skb_list(skb);
 4527	return rc;
 4528out:
 4529	rcu_read_unlock_bh();
 4530	return rc;
 4531}
 4532EXPORT_SYMBOL(__dev_queue_xmit);
 4533
 4534int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id)
 4535{
 4536	struct net_device *dev = skb->dev;
 4537	struct sk_buff *orig_skb = skb;
 4538	struct netdev_queue *txq;
 4539	int ret = NETDEV_TX_BUSY;
 4540	bool again = false;
 4541
 4542	if (unlikely(!netif_running(dev) ||
 4543		     !netif_carrier_ok(dev)))
 4544		goto drop;
 4545
 4546	skb = validate_xmit_skb_list(skb, dev, &again);
 4547	if (skb != orig_skb)
 4548		goto drop;
 4549
 4550	skb_set_queue_mapping(skb, queue_id);
 4551	txq = skb_get_tx_queue(dev, skb);
 4552
 4553	local_bh_disable();
 4554
 4555	dev_xmit_recursion_inc();
 4556	HARD_TX_LOCK(dev, txq, smp_processor_id());
 4557	if (!netif_xmit_frozen_or_drv_stopped(txq))
 4558		ret = netdev_start_xmit(skb, dev, txq, false);
 4559	HARD_TX_UNLOCK(dev, txq);
 4560	dev_xmit_recursion_dec();
 4561
 4562	local_bh_enable();
 4563	return ret;
 4564drop:
 4565	dev_core_stats_tx_dropped_inc(dev);
 4566	kfree_skb_list(skb);
 4567	return NET_XMIT_DROP;
 4568}
 4569EXPORT_SYMBOL(__dev_direct_xmit);
 4570
 4571/*************************************************************************
 4572 *			Receiver routines
 4573 *************************************************************************/
 4574static DEFINE_PER_CPU(struct task_struct *, backlog_napi);
 4575
 4576int weight_p __read_mostly = 64;           /* old backlog weight */
 4577int dev_weight_rx_bias __read_mostly = 1;  /* bias for backlog weight */
 4578int dev_weight_tx_bias __read_mostly = 1;  /* bias for output_queue quota */
 4579
 4580/* Called with irq disabled */
 4581static inline void ____napi_schedule(struct softnet_data *sd,
 4582				     struct napi_struct *napi)
 4583{
 4584	struct task_struct *thread;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 4585
 4586	lockdep_assert_irqs_disabled();
 4587
 4588	if (test_bit(NAPI_STATE_THREADED, &napi->state)) {
 4589		/* Paired with smp_mb__before_atomic() in
 4590		 * napi_enable()/dev_set_threaded().
 4591		 * Use READ_ONCE() to guarantee a complete
 4592		 * read on napi->thread. Only call
 4593		 * wake_up_process() when it's not NULL.
 4594		 */
 4595		thread = READ_ONCE(napi->thread);
 4596		if (thread) {
 4597			if (use_backlog_threads() && thread == raw_cpu_read(backlog_napi))
 4598				goto use_local_napi;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 4599
 4600			set_bit(NAPI_STATE_SCHED_THREADED, &napi->state);
 4601			wake_up_process(thread);
 4602			return;
 
 
 
 
 
 4603		}
 4604	}
 4605
 4606use_local_napi:
 4607	list_add_tail(&napi->poll_list, &sd->poll_list);
 4608	WRITE_ONCE(napi->list_owner, smp_processor_id());
 4609	/* If not called from net_rx_action()
 4610	 * we have to raise NET_RX_SOFTIRQ.
 4611	 */
 4612	if (!sd->in_net_rx_action)
 4613		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
 
 
 4614}
 
 4615
 4616#ifdef CONFIG_RPS
 4617
 4618struct static_key_false rps_needed __read_mostly;
 4619EXPORT_SYMBOL(rps_needed);
 4620struct static_key_false rfs_needed __read_mostly;
 4621EXPORT_SYMBOL(rfs_needed);
 4622
 4623static struct rps_dev_flow *
 4624set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
 4625	    struct rps_dev_flow *rflow, u16 next_cpu)
 4626{
 4627	if (next_cpu < nr_cpu_ids) {
 4628		u32 head;
 
 
 4629#ifdef CONFIG_RFS_ACCEL
 4630		struct netdev_rx_queue *rxqueue;
 4631		struct rps_dev_flow_table *flow_table;
 4632		struct rps_dev_flow *old_rflow;
 4633		u16 rxq_index;
 4634		u32 flow_id;
 
 4635		int rc;
 4636
 4637		/* Should we steer this flow to a different hardware queue? */
 4638		if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
 4639		    !(dev->features & NETIF_F_NTUPLE))
 4640			goto out;
 4641		rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
 4642		if (rxq_index == skb_get_rx_queue(skb))
 4643			goto out;
 4644
 4645		rxqueue = dev->_rx + rxq_index;
 4646		flow_table = rcu_dereference(rxqueue->rps_flow_table);
 4647		if (!flow_table)
 4648			goto out;
 4649		flow_id = skb_get_hash(skb) & flow_table->mask;
 4650		rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
 4651							rxq_index, flow_id);
 4652		if (rc < 0)
 4653			goto out;
 4654		old_rflow = rflow;
 4655		rflow = &flow_table->flows[flow_id];
 4656		WRITE_ONCE(rflow->filter, rc);
 4657		if (old_rflow->filter == rc)
 4658			WRITE_ONCE(old_rflow->filter, RPS_NO_FILTER);
 
 4659	out:
 4660#endif
 4661		head = READ_ONCE(per_cpu(softnet_data, next_cpu).input_queue_head);
 4662		rps_input_queue_tail_save(&rflow->last_qtail, head);
 4663	}
 4664
 4665	WRITE_ONCE(rflow->cpu, next_cpu);
 4666	return rflow;
 4667}
 4668
 4669/*
 4670 * get_rps_cpu is called from netif_receive_skb and returns the target
 4671 * CPU from the RPS map of the receiving queue for a given skb.
 4672 * rcu_read_lock must be held on entry.
 4673 */
 4674static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
 4675		       struct rps_dev_flow **rflowp)
 4676{
 4677	const struct rps_sock_flow_table *sock_flow_table;
 4678	struct netdev_rx_queue *rxqueue = dev->_rx;
 4679	struct rps_dev_flow_table *flow_table;
 4680	struct rps_map *map;
 
 
 4681	int cpu = -1;
 4682	u32 tcpu;
 4683	u32 hash;
 4684
 4685	if (skb_rx_queue_recorded(skb)) {
 4686		u16 index = skb_get_rx_queue(skb);
 4687
 4688		if (unlikely(index >= dev->real_num_rx_queues)) {
 4689			WARN_ONCE(dev->real_num_rx_queues > 1,
 4690				  "%s received packet on queue %u, but number "
 4691				  "of RX queues is %u\n",
 4692				  dev->name, index, dev->real_num_rx_queues);
 4693			goto done;
 4694		}
 4695		rxqueue += index;
 4696	}
 4697
 4698	/* Avoid computing hash if RFS/RPS is not active for this rxqueue */
 4699
 4700	flow_table = rcu_dereference(rxqueue->rps_flow_table);
 4701	map = rcu_dereference(rxqueue->rps_map);
 4702	if (!flow_table && !map)
 
 
 
 
 
 
 
 
 4703		goto done;
 
 4704
 4705	skb_reset_network_header(skb);
 4706	hash = skb_get_hash(skb);
 4707	if (!hash)
 4708		goto done;
 4709
 4710	sock_flow_table = rcu_dereference(net_hotdata.rps_sock_flow_table);
 
 4711	if (flow_table && sock_flow_table) {
 
 4712		struct rps_dev_flow *rflow;
 4713		u32 next_cpu;
 4714		u32 ident;
 4715
 4716		/* First check into global flow table if there is a match.
 4717		 * This READ_ONCE() pairs with WRITE_ONCE() from rps_record_sock_flow().
 4718		 */
 4719		ident = READ_ONCE(sock_flow_table->ents[hash & sock_flow_table->mask]);
 4720		if ((ident ^ hash) & ~net_hotdata.rps_cpu_mask)
 4721			goto try_rps;
 4722
 4723		next_cpu = ident & net_hotdata.rps_cpu_mask;
 4724
 4725		/* OK, now we know there is a match,
 4726		 * we can look at the local (per receive queue) flow table
 4727		 */
 4728		rflow = &flow_table->flows[hash & flow_table->mask];
 4729		tcpu = rflow->cpu;
 4730
 
 
 
 4731		/*
 4732		 * If the desired CPU (where last recvmsg was done) is
 4733		 * different from current CPU (one in the rx-queue flow
 4734		 * table entry), switch if one of the following holds:
 4735		 *   - Current CPU is unset (>= nr_cpu_ids).
 4736		 *   - Current CPU is offline.
 4737		 *   - The current CPU's queue tail has advanced beyond the
 4738		 *     last packet that was enqueued using this table entry.
 4739		 *     This guarantees that all previous packets for the flow
 4740		 *     have been dequeued, thus preserving in order delivery.
 4741		 */
 4742		if (unlikely(tcpu != next_cpu) &&
 4743		    (tcpu >= nr_cpu_ids || !cpu_online(tcpu) ||
 4744		     ((int)(READ_ONCE(per_cpu(softnet_data, tcpu).input_queue_head) -
 4745		      rflow->last_qtail)) >= 0)) {
 4746			tcpu = next_cpu;
 4747			rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
 4748		}
 4749
 4750		if (tcpu < nr_cpu_ids && cpu_online(tcpu)) {
 4751			*rflowp = rflow;
 4752			cpu = tcpu;
 4753			goto done;
 4754		}
 4755	}
 4756
 4757try_rps:
 4758
 4759	if (map) {
 4760		tcpu = map->cpus[reciprocal_scale(hash, map->len)];
 
 4761		if (cpu_online(tcpu)) {
 4762			cpu = tcpu;
 4763			goto done;
 4764		}
 4765	}
 4766
 4767done:
 4768	return cpu;
 4769}
 4770
 4771#ifdef CONFIG_RFS_ACCEL
 4772
 4773/**
 4774 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
 4775 * @dev: Device on which the filter was set
 4776 * @rxq_index: RX queue index
 4777 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
 4778 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
 4779 *
 4780 * Drivers that implement ndo_rx_flow_steer() should periodically call
 4781 * this function for each installed filter and remove the filters for
 4782 * which it returns %true.
 4783 */
 4784bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
 4785			 u32 flow_id, u16 filter_id)
 4786{
 4787	struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
 4788	struct rps_dev_flow_table *flow_table;
 4789	struct rps_dev_flow *rflow;
 4790	bool expire = true;
 4791	unsigned int cpu;
 4792
 4793	rcu_read_lock();
 4794	flow_table = rcu_dereference(rxqueue->rps_flow_table);
 4795	if (flow_table && flow_id <= flow_table->mask) {
 4796		rflow = &flow_table->flows[flow_id];
 4797		cpu = READ_ONCE(rflow->cpu);
 4798		if (READ_ONCE(rflow->filter) == filter_id && cpu < nr_cpu_ids &&
 4799		    ((int)(READ_ONCE(per_cpu(softnet_data, cpu).input_queue_head) -
 4800			   READ_ONCE(rflow->last_qtail)) <
 4801		     (int)(10 * flow_table->mask)))
 4802			expire = false;
 4803	}
 4804	rcu_read_unlock();
 4805	return expire;
 4806}
 4807EXPORT_SYMBOL(rps_may_expire_flow);
 4808
 4809#endif /* CONFIG_RFS_ACCEL */
 4810
 4811/* Called from hardirq (IPI) context */
 4812static void rps_trigger_softirq(void *data)
 4813{
 4814	struct softnet_data *sd = data;
 4815
 4816	____napi_schedule(sd, &sd->backlog);
 4817	sd->received_rps++;
 4818}
 4819
 4820#endif /* CONFIG_RPS */
 4821
 4822/* Called from hardirq (IPI) context */
 4823static void trigger_rx_softirq(void *data)
 4824{
 4825	struct softnet_data *sd = data;
 4826
 4827	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
 4828	smp_store_release(&sd->defer_ipi_scheduled, 0);
 4829}
 4830
 4831/*
 4832 * After we queued a packet into sd->input_pkt_queue,
 4833 * we need to make sure this queue is serviced soon.
 4834 *
 4835 * - If this is another cpu queue, link it to our rps_ipi_list,
 4836 *   and make sure we will process rps_ipi_list from net_rx_action().
 4837 *
 4838 * - If this is our own queue, NAPI schedule our backlog.
 4839 *   Note that this also raises NET_RX_SOFTIRQ.
 4840 */
 4841static void napi_schedule_rps(struct softnet_data *sd)
 4842{
 4843	struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
 4844
 4845#ifdef CONFIG_RPS
 4846	if (sd != mysd) {
 4847		if (use_backlog_threads()) {
 4848			__napi_schedule_irqoff(&sd->backlog);
 4849			return;
 4850		}
 4851
 
 4852		sd->rps_ipi_next = mysd->rps_ipi_list;
 4853		mysd->rps_ipi_list = sd;
 4854
 4855		/* If not called from net_rx_action() or napi_threaded_poll()
 4856		 * we have to raise NET_RX_SOFTIRQ.
 4857		 */
 4858		if (!mysd->in_net_rx_action && !mysd->in_napi_threaded_poll)
 4859			__raise_softirq_irqoff(NET_RX_SOFTIRQ);
 4860		return;
 4861	}
 4862#endif /* CONFIG_RPS */
 4863	__napi_schedule_irqoff(&mysd->backlog);
 4864}
 4865
 4866void kick_defer_list_purge(struct softnet_data *sd, unsigned int cpu)
 4867{
 4868	unsigned long flags;
 4869
 4870	if (use_backlog_threads()) {
 4871		backlog_lock_irq_save(sd, &flags);
 4872
 4873		if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state))
 4874			__napi_schedule_irqoff(&sd->backlog);
 4875
 4876		backlog_unlock_irq_restore(sd, &flags);
 4877
 4878	} else if (!cmpxchg(&sd->defer_ipi_scheduled, 0, 1)) {
 4879		smp_call_function_single_async(cpu, &sd->defer_csd);
 4880	}
 4881}
 4882
 4883#ifdef CONFIG_NET_FLOW_LIMIT
 4884int netdev_flow_limit_table_len __read_mostly = (1 << 12);
 4885#endif
 4886
 4887static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
 4888{
 4889#ifdef CONFIG_NET_FLOW_LIMIT
 4890	struct sd_flow_limit *fl;
 4891	struct softnet_data *sd;
 4892	unsigned int old_flow, new_flow;
 4893
 4894	if (qlen < (READ_ONCE(net_hotdata.max_backlog) >> 1))
 4895		return false;
 4896
 4897	sd = this_cpu_ptr(&softnet_data);
 4898
 4899	rcu_read_lock();
 4900	fl = rcu_dereference(sd->flow_limit);
 4901	if (fl) {
 4902		new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
 4903		old_flow = fl->history[fl->history_head];
 4904		fl->history[fl->history_head] = new_flow;
 4905
 4906		fl->history_head++;
 4907		fl->history_head &= FLOW_LIMIT_HISTORY - 1;
 4908
 4909		if (likely(fl->buckets[old_flow]))
 4910			fl->buckets[old_flow]--;
 4911
 4912		if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
 4913			fl->count++;
 4914			rcu_read_unlock();
 4915			return true;
 4916		}
 4917	}
 4918	rcu_read_unlock();
 4919#endif
 4920	return false;
 4921}
 4922
 4923/*
 4924 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
 4925 * queue (may be a remote CPU queue).
 4926 */
 4927static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
 4928			      unsigned int *qtail)
 4929{
 4930	enum skb_drop_reason reason;
 4931	struct softnet_data *sd;
 4932	unsigned long flags;
 4933	unsigned int qlen;
 4934	int max_backlog;
 4935	u32 tail;
 4936
 4937	reason = SKB_DROP_REASON_DEV_READY;
 4938	if (!netif_running(skb->dev))
 4939		goto bad_dev;
 4940
 4941	reason = SKB_DROP_REASON_CPU_BACKLOG;
 4942	sd = &per_cpu(softnet_data, cpu);
 4943
 4944	qlen = skb_queue_len_lockless(&sd->input_pkt_queue);
 4945	max_backlog = READ_ONCE(net_hotdata.max_backlog);
 4946	if (unlikely(qlen > max_backlog))
 4947		goto cpu_backlog_drop;
 4948	backlog_lock_irq_save(sd, &flags);
 4949	qlen = skb_queue_len(&sd->input_pkt_queue);
 4950	if (qlen <= max_backlog && !skb_flow_limit(skb, qlen)) {
 4951		if (!qlen) {
 4952			/* Schedule NAPI for backlog device. We can use
 4953			 * non atomic operation as we own the queue lock.
 4954			 */
 4955			if (!__test_and_set_bit(NAPI_STATE_SCHED,
 4956						&sd->backlog.state))
 4957				napi_schedule_rps(sd);
 4958		}
 4959		__skb_queue_tail(&sd->input_pkt_queue, skb);
 4960		tail = rps_input_queue_tail_incr(sd);
 4961		backlog_unlock_irq_restore(sd, &flags);
 4962
 4963		/* save the tail outside of the critical section */
 4964		rps_input_queue_tail_save(qtail, tail);
 4965		return NET_RX_SUCCESS;
 4966	}
 4967
 4968	backlog_unlock_irq_restore(sd, &flags);
 4969
 4970cpu_backlog_drop:
 4971	atomic_inc(&sd->dropped);
 4972bad_dev:
 4973	dev_core_stats_rx_dropped_inc(skb->dev);
 4974	kfree_skb_reason(skb, reason);
 4975	return NET_RX_DROP;
 4976}
 4977
 4978static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb)
 4979{
 4980	struct net_device *dev = skb->dev;
 4981	struct netdev_rx_queue *rxqueue;
 4982
 4983	rxqueue = dev->_rx;
 4984
 4985	if (skb_rx_queue_recorded(skb)) {
 4986		u16 index = skb_get_rx_queue(skb);
 4987
 4988		if (unlikely(index >= dev->real_num_rx_queues)) {
 4989			WARN_ONCE(dev->real_num_rx_queues > 1,
 4990				  "%s received packet on queue %u, but number "
 4991				  "of RX queues is %u\n",
 4992				  dev->name, index, dev->real_num_rx_queues);
 4993
 4994			return rxqueue; /* Return first rxqueue */
 
 
 
 
 
 
 
 
 4995		}
 4996		rxqueue += index;
 4997	}
 4998	return rxqueue;
 4999}
 5000
 5001u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp,
 5002			     struct bpf_prog *xdp_prog)
 5003{
 5004	void *orig_data, *orig_data_end, *hard_start;
 5005	struct netdev_rx_queue *rxqueue;
 5006	bool orig_bcast, orig_host;
 5007	u32 mac_len, frame_sz;
 5008	__be16 orig_eth_type;
 5009	struct ethhdr *eth;
 5010	u32 metalen, act;
 5011	int off;
 5012
 5013	/* The XDP program wants to see the packet starting at the MAC
 5014	 * header.
 5015	 */
 5016	mac_len = skb->data - skb_mac_header(skb);
 5017	hard_start = skb->data - skb_headroom(skb);
 5018
 5019	/* SKB "head" area always have tailroom for skb_shared_info */
 5020	frame_sz = (void *)skb_end_pointer(skb) - hard_start;
 5021	frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
 5022
 5023	rxqueue = netif_get_rxqueue(skb);
 5024	xdp_init_buff(xdp, frame_sz, &rxqueue->xdp_rxq);
 5025	xdp_prepare_buff(xdp, hard_start, skb_headroom(skb) - mac_len,
 5026			 skb_headlen(skb) + mac_len, true);
 5027	if (skb_is_nonlinear(skb)) {
 5028		skb_shinfo(skb)->xdp_frags_size = skb->data_len;
 5029		xdp_buff_set_frags_flag(xdp);
 5030	} else {
 5031		xdp_buff_clear_frags_flag(xdp);
 5032	}
 5033
 5034	orig_data_end = xdp->data_end;
 5035	orig_data = xdp->data;
 5036	eth = (struct ethhdr *)xdp->data;
 5037	orig_host = ether_addr_equal_64bits(eth->h_dest, skb->dev->dev_addr);
 5038	orig_bcast = is_multicast_ether_addr_64bits(eth->h_dest);
 5039	orig_eth_type = eth->h_proto;
 5040
 5041	act = bpf_prog_run_xdp(xdp_prog, xdp);
 5042
 5043	/* check if bpf_xdp_adjust_head was used */
 5044	off = xdp->data - orig_data;
 5045	if (off) {
 5046		if (off > 0)
 5047			__skb_pull(skb, off);
 5048		else if (off < 0)
 5049			__skb_push(skb, -off);
 5050
 5051		skb->mac_header += off;
 5052		skb_reset_network_header(skb);
 5053	}
 5054
 5055	/* check if bpf_xdp_adjust_tail was used */
 5056	off = xdp->data_end - orig_data_end;
 5057	if (off != 0) {
 5058		skb_set_tail_pointer(skb, xdp->data_end - xdp->data);
 5059		skb->len += off; /* positive on grow, negative on shrink */
 5060	}
 5061
 5062	/* XDP frag metadata (e.g. nr_frags) are updated in eBPF helpers
 5063	 * (e.g. bpf_xdp_adjust_tail), we need to update data_len here.
 5064	 */
 5065	if (xdp_buff_has_frags(xdp))
 5066		skb->data_len = skb_shinfo(skb)->xdp_frags_size;
 5067	else
 5068		skb->data_len = 0;
 5069
 5070	/* check if XDP changed eth hdr such SKB needs update */
 5071	eth = (struct ethhdr *)xdp->data;
 5072	if ((orig_eth_type != eth->h_proto) ||
 5073	    (orig_host != ether_addr_equal_64bits(eth->h_dest,
 5074						  skb->dev->dev_addr)) ||
 5075	    (orig_bcast != is_multicast_ether_addr_64bits(eth->h_dest))) {
 5076		__skb_push(skb, ETH_HLEN);
 5077		skb->pkt_type = PACKET_HOST;
 5078		skb->protocol = eth_type_trans(skb, skb->dev);
 5079	}
 5080
 5081	/* Redirect/Tx gives L2 packet, code that will reuse skb must __skb_pull
 5082	 * before calling us again on redirect path. We do not call do_redirect
 5083	 * as we leave that up to the caller.
 5084	 *
 5085	 * Caller is responsible for managing lifetime of skb (i.e. calling
 5086	 * kfree_skb in response to actions it cannot handle/XDP_DROP).
 5087	 */
 5088	switch (act) {
 5089	case XDP_REDIRECT:
 5090	case XDP_TX:
 5091		__skb_push(skb, mac_len);
 5092		break;
 5093	case XDP_PASS:
 5094		metalen = xdp->data - xdp->data_meta;
 5095		if (metalen)
 5096			skb_metadata_set(skb, metalen);
 5097		break;
 5098	}
 5099
 5100	return act;
 5101}
 5102
 5103static int
 5104netif_skb_check_for_xdp(struct sk_buff **pskb, struct bpf_prog *prog)
 5105{
 5106	struct sk_buff *skb = *pskb;
 5107	int err, hroom, troom;
 5108
 5109	if (!skb_cow_data_for_xdp(this_cpu_read(system_page_pool), pskb, prog))
 5110		return 0;
 5111
 5112	/* In case we have to go down the path and also linearize,
 5113	 * then lets do the pskb_expand_head() work just once here.
 5114	 */
 5115	hroom = XDP_PACKET_HEADROOM - skb_headroom(skb);
 5116	troom = skb->tail + skb->data_len - skb->end;
 5117	err = pskb_expand_head(skb,
 5118			       hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0,
 5119			       troom > 0 ? troom + 128 : 0, GFP_ATOMIC);
 5120	if (err)
 5121		return err;
 5122
 5123	return skb_linearize(skb);
 5124}
 5125
 5126static u32 netif_receive_generic_xdp(struct sk_buff **pskb,
 5127				     struct xdp_buff *xdp,
 5128				     struct bpf_prog *xdp_prog)
 5129{
 5130	struct sk_buff *skb = *pskb;
 5131	u32 mac_len, act = XDP_DROP;
 5132
 5133	/* Reinjected packets coming from act_mirred or similar should
 5134	 * not get XDP generic processing.
 5135	 */
 5136	if (skb_is_redirected(skb))
 5137		return XDP_PASS;
 5138
 5139	/* XDP packets must have sufficient headroom of XDP_PACKET_HEADROOM
 5140	 * bytes. This is the guarantee that also native XDP provides,
 5141	 * thus we need to do it here as well.
 5142	 */
 5143	mac_len = skb->data - skb_mac_header(skb);
 5144	__skb_push(skb, mac_len);
 5145
 5146	if (skb_cloned(skb) || skb_is_nonlinear(skb) ||
 5147	    skb_headroom(skb) < XDP_PACKET_HEADROOM) {
 5148		if (netif_skb_check_for_xdp(pskb, xdp_prog))
 5149			goto do_drop;
 5150	}
 5151
 5152	__skb_pull(*pskb, mac_len);
 
 5153
 5154	act = bpf_prog_run_generic_xdp(*pskb, xdp, xdp_prog);
 5155	switch (act) {
 5156	case XDP_REDIRECT:
 5157	case XDP_TX:
 5158	case XDP_PASS:
 5159		break;
 5160	default:
 5161		bpf_warn_invalid_xdp_action((*pskb)->dev, xdp_prog, act);
 5162		fallthrough;
 5163	case XDP_ABORTED:
 5164		trace_xdp_exception((*pskb)->dev, xdp_prog, act);
 5165		fallthrough;
 5166	case XDP_DROP:
 5167	do_drop:
 5168		kfree_skb(*pskb);
 5169		break;
 5170	}
 5171
 5172	return act;
 
 
 5173}
 5174
 5175/* When doing generic XDP we have to bypass the qdisc layer and the
 5176 * network taps in order to match in-driver-XDP behavior. This also means
 5177 * that XDP packets are able to starve other packets going through a qdisc,
 5178 * and DDOS attacks will be more effective. In-driver-XDP use dedicated TX
 5179 * queues, so they do not have this starvation issue.
 
 
 
 
 
 
 
 
 5180 */
 5181void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog)
 5182{
 5183	struct net_device *dev = skb->dev;
 5184	struct netdev_queue *txq;
 5185	bool free_skb = true;
 5186	int cpu, rc;
 5187
 5188	txq = netdev_core_pick_tx(dev, skb, NULL);
 5189	cpu = smp_processor_id();
 5190	HARD_TX_LOCK(dev, txq, cpu);
 5191	if (!netif_xmit_frozen_or_drv_stopped(txq)) {
 5192		rc = netdev_start_xmit(skb, dev, txq, 0);
 5193		if (dev_xmit_complete(rc))
 5194			free_skb = false;
 5195	}
 5196	HARD_TX_UNLOCK(dev, txq);
 5197	if (free_skb) {
 5198		trace_xdp_exception(dev, xdp_prog, XDP_TX);
 5199		dev_core_stats_tx_dropped_inc(dev);
 5200		kfree_skb(skb);
 5201	}
 5202}
 5203
 5204static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key);
 5205
 5206int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff **pskb)
 5207{
 5208	struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx;
 5209
 5210	if (xdp_prog) {
 5211		struct xdp_buff xdp;
 5212		u32 act;
 5213		int err;
 5214
 5215		bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx);
 5216		act = netif_receive_generic_xdp(pskb, &xdp, xdp_prog);
 5217		if (act != XDP_PASS) {
 5218			switch (act) {
 5219			case XDP_REDIRECT:
 5220				err = xdp_do_generic_redirect((*pskb)->dev, *pskb,
 5221							      &xdp, xdp_prog);
 5222				if (err)
 5223					goto out_redir;
 5224				break;
 5225			case XDP_TX:
 5226				generic_xdp_tx(*pskb, xdp_prog);
 5227				break;
 5228			}
 5229			bpf_net_ctx_clear(bpf_net_ctx);
 5230			return XDP_DROP;
 5231		}
 5232		bpf_net_ctx_clear(bpf_net_ctx);
 5233	}
 5234	return XDP_PASS;
 5235out_redir:
 5236	bpf_net_ctx_clear(bpf_net_ctx);
 5237	kfree_skb_reason(*pskb, SKB_DROP_REASON_XDP);
 5238	return XDP_DROP;
 5239}
 5240EXPORT_SYMBOL_GPL(do_xdp_generic);
 5241
 5242static int netif_rx_internal(struct sk_buff *skb)
 5243{
 5244	int ret;
 5245
 5246	net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), skb);
 
 
 5247
 5248	trace_netif_rx(skb);
 
 5249
 
 5250#ifdef CONFIG_RPS
 5251	if (static_branch_unlikely(&rps_needed)) {
 5252		struct rps_dev_flow voidflow, *rflow = &voidflow;
 5253		int cpu;
 5254
 
 5255		rcu_read_lock();
 5256
 5257		cpu = get_rps_cpu(skb->dev, skb, &rflow);
 5258		if (cpu < 0)
 5259			cpu = smp_processor_id();
 5260
 5261		ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
 5262
 5263		rcu_read_unlock();
 5264	} else
 5265#endif
 
 5266	{
 5267		unsigned int qtail;
 5268
 5269		ret = enqueue_to_backlog(skb, smp_processor_id(), &qtail);
 5270	}
 
 5271	return ret;
 5272}
 
 5273
 5274/**
 5275 *	__netif_rx	-	Slightly optimized version of netif_rx
 5276 *	@skb: buffer to post
 5277 *
 5278 *	This behaves as netif_rx except that it does not disable bottom halves.
 5279 *	As a result this function may only be invoked from the interrupt context
 5280 *	(either hard or soft interrupt).
 5281 */
 5282int __netif_rx(struct sk_buff *skb)
 5283{
 5284	int ret;
 5285
 5286	lockdep_assert_once(hardirq_count() | softirq_count());
 5287
 5288	trace_netif_rx_entry(skb);
 5289	ret = netif_rx_internal(skb);
 5290	trace_netif_rx_exit(ret);
 5291	return ret;
 5292}
 5293EXPORT_SYMBOL(__netif_rx);
 5294
 5295/**
 5296 *	netif_rx	-	post buffer to the network code
 5297 *	@skb: buffer to post
 5298 *
 5299 *	This function receives a packet from a device driver and queues it for
 5300 *	the upper (protocol) levels to process via the backlog NAPI device. It
 5301 *	always succeeds. The buffer may be dropped during processing for
 5302 *	congestion control or by the protocol layers.
 5303 *	The network buffer is passed via the backlog NAPI device. Modern NIC
 5304 *	driver should use NAPI and GRO.
 5305 *	This function can used from interrupt and from process context. The
 5306 *	caller from process context must not disable interrupts before invoking
 5307 *	this function.
 5308 *
 5309 *	return values:
 5310 *	NET_RX_SUCCESS	(no congestion)
 5311 *	NET_RX_DROP     (packet was dropped)
 5312 *
 5313 */
 5314int netif_rx(struct sk_buff *skb)
 5315{
 5316	bool need_bh_off = !(hardirq_count() | softirq_count());
 5317	int ret;
 5318
 5319	if (need_bh_off)
 5320		local_bh_disable();
 5321	trace_netif_rx_entry(skb);
 5322	ret = netif_rx_internal(skb);
 5323	trace_netif_rx_exit(ret);
 5324	if (need_bh_off)
 5325		local_bh_enable();
 5326	return ret;
 5327}
 5328EXPORT_SYMBOL(netif_rx);
 5329
 5330static __latent_entropy void net_tx_action(void)
 5331{
 5332	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
 5333
 5334	if (sd->completion_queue) {
 5335		struct sk_buff *clist;
 5336
 5337		local_irq_disable();
 5338		clist = sd->completion_queue;
 5339		sd->completion_queue = NULL;
 5340		local_irq_enable();
 5341
 5342		while (clist) {
 5343			struct sk_buff *skb = clist;
 5344
 5345			clist = clist->next;
 5346
 5347			WARN_ON(refcount_read(&skb->users));
 5348			if (likely(get_kfree_skb_cb(skb)->reason == SKB_CONSUMED))
 5349				trace_consume_skb(skb, net_tx_action);
 5350			else
 5351				trace_kfree_skb(skb, net_tx_action,
 5352						get_kfree_skb_cb(skb)->reason, NULL);
 5353
 5354			if (skb->fclone != SKB_FCLONE_UNAVAILABLE)
 5355				__kfree_skb(skb);
 5356			else
 5357				__napi_kfree_skb(skb,
 5358						 get_kfree_skb_cb(skb)->reason);
 5359		}
 5360	}
 5361
 5362	if (sd->output_queue) {
 5363		struct Qdisc *head;
 5364
 5365		local_irq_disable();
 5366		head = sd->output_queue;
 5367		sd->output_queue = NULL;
 5368		sd->output_queue_tailp = &sd->output_queue;
 5369		local_irq_enable();
 5370
 5371		rcu_read_lock();
 5372
 5373		while (head) {
 5374			struct Qdisc *q = head;
 5375			spinlock_t *root_lock = NULL;
 5376
 5377			head = head->next_sched;
 5378
 5379			/* We need to make sure head->next_sched is read
 5380			 * before clearing __QDISC_STATE_SCHED
 5381			 */
 5382			smp_mb__before_atomic();
 5383
 5384			if (!(q->flags & TCQ_F_NOLOCK)) {
 5385				root_lock = qdisc_lock(q);
 5386				spin_lock(root_lock);
 5387			} else if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED,
 5388						     &q->state))) {
 5389				/* There is a synchronize_net() between
 5390				 * STATE_DEACTIVATED flag being set and
 5391				 * qdisc_reset()/some_qdisc_is_busy() in
 5392				 * dev_deactivate(), so we can safely bail out
 5393				 * early here to avoid data race between
 5394				 * qdisc_deactivate() and some_qdisc_is_busy()
 5395				 * for lockless qdisc.
 5396				 */
 5397				clear_bit(__QDISC_STATE_SCHED, &q->state);
 5398				continue;
 5399			}
 5400
 5401			clear_bit(__QDISC_STATE_SCHED, &q->state);
 5402			qdisc_run(q);
 5403			if (root_lock)
 5404				spin_unlock(root_lock);
 
 
 
 
 
 
 
 
 
 
 5405		}
 5406
 5407		rcu_read_unlock();
 5408	}
 5409
 5410	xfrm_dev_backlog(sd);
 5411}
 5412
 5413#if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE)
 
 5414/* This hook is defined here for ATM LANE */
 5415int (*br_fdb_test_addr_hook)(struct net_device *dev,
 5416			     unsigned char *addr) __read_mostly;
 5417EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
 5418#endif
 5419
 5420/**
 5421 *	netdev_is_rx_handler_busy - check if receive handler is registered
 5422 *	@dev: device to check
 5423 *
 5424 *	Check if a receive handler is already registered for a given device.
 5425 *	Return true if there one.
 
 5426 *
 5427 *	The caller must hold the rtnl_mutex.
 5428 */
 5429bool netdev_is_rx_handler_busy(struct net_device *dev)
 5430{
 5431	ASSERT_RTNL();
 5432	return dev && rtnl_dereference(dev->rx_handler);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 5433}
 5434EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy);
 5435
 5436/**
 5437 *	netdev_rx_handler_register - register receive handler
 5438 *	@dev: device to register a handler for
 5439 *	@rx_handler: receive handler to register
 5440 *	@rx_handler_data: data pointer that is used by rx handler
 5441 *
 5442 *	Register a receive handler for a device. This handler will then be
 5443 *	called from __netif_receive_skb. A negative errno code is returned
 5444 *	on a failure.
 5445 *
 5446 *	The caller must hold the rtnl_mutex.
 5447 *
 5448 *	For a general description of rx_handler, see enum rx_handler_result.
 5449 */
 5450int netdev_rx_handler_register(struct net_device *dev,
 5451			       rx_handler_func_t *rx_handler,
 5452			       void *rx_handler_data)
 5453{
 5454	if (netdev_is_rx_handler_busy(dev))
 5455		return -EBUSY;
 5456
 5457	if (dev->priv_flags & IFF_NO_RX_HANDLER)
 5458		return -EINVAL;
 5459
 5460	/* Note: rx_handler_data must be set before rx_handler */
 5461	rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
 5462	rcu_assign_pointer(dev->rx_handler, rx_handler);
 5463
 5464	return 0;
 5465}
 5466EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
 5467
 5468/**
 5469 *	netdev_rx_handler_unregister - unregister receive handler
 5470 *	@dev: device to unregister a handler from
 5471 *
 5472 *	Unregister a receive handler from a device.
 5473 *
 5474 *	The caller must hold the rtnl_mutex.
 5475 */
 5476void netdev_rx_handler_unregister(struct net_device *dev)
 5477{
 5478
 5479	ASSERT_RTNL();
 5480	RCU_INIT_POINTER(dev->rx_handler, NULL);
 5481	/* a reader seeing a non NULL rx_handler in a rcu_read_lock()
 5482	 * section has a guarantee to see a non NULL rx_handler_data
 5483	 * as well.
 5484	 */
 5485	synchronize_net();
 5486	RCU_INIT_POINTER(dev->rx_handler_data, NULL);
 5487}
 5488EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
 5489
 5490/*
 5491 * Limit the use of PFMEMALLOC reserves to those protocols that implement
 5492 * the special handling of PFMEMALLOC skbs.
 5493 */
 5494static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
 5495{
 5496	switch (skb->protocol) {
 5497	case htons(ETH_P_ARP):
 5498	case htons(ETH_P_IP):
 5499	case htons(ETH_P_IPV6):
 5500	case htons(ETH_P_8021Q):
 5501	case htons(ETH_P_8021AD):
 5502		return true;
 5503	default:
 5504		return false;
 5505	}
 5506}
 5507
 5508static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev,
 5509			     int *ret, struct net_device *orig_dev)
 5510{
 5511	if (nf_hook_ingress_active(skb)) {
 5512		int ingress_retval;
 5513
 5514		if (*pt_prev) {
 5515			*ret = deliver_skb(skb, *pt_prev, orig_dev);
 5516			*pt_prev = NULL;
 5517		}
 5518
 5519		rcu_read_lock();
 5520		ingress_retval = nf_hook_ingress(skb);
 5521		rcu_read_unlock();
 5522		return ingress_retval;
 5523	}
 5524	return 0;
 5525}
 5526
 5527static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc,
 5528				    struct packet_type **ppt_prev)
 5529{
 5530	struct packet_type *ptype, *pt_prev;
 5531	rx_handler_func_t *rx_handler;
 5532	struct sk_buff *skb = *pskb;
 5533	struct net_device *orig_dev;
 
 5534	bool deliver_exact = false;
 5535	int ret = NET_RX_DROP;
 5536	__be16 type;
 5537
 5538	net_timestamp_check(!READ_ONCE(net_hotdata.tstamp_prequeue), skb);
 
 5539
 5540	trace_netif_receive_skb(skb);
 5541
 
 
 
 
 
 
 5542	orig_dev = skb->dev;
 5543
 5544	skb_reset_network_header(skb);
 5545	if (!skb_transport_header_was_set(skb))
 5546		skb_reset_transport_header(skb);
 5547	skb_reset_mac_len(skb);
 5548
 5549	pt_prev = NULL;
 5550
 
 
 5551another_round:
 5552	skb->skb_iif = skb->dev->ifindex;
 5553
 5554	__this_cpu_inc(softnet_data.processed);
 5555
 5556	if (static_branch_unlikely(&generic_xdp_needed_key)) {
 5557		int ret2;
 5558
 5559		migrate_disable();
 5560		ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog),
 5561				      &skb);
 5562		migrate_enable();
 5563
 5564		if (ret2 != XDP_PASS) {
 5565			ret = NET_RX_DROP;
 5566			goto out;
 5567		}
 5568	}
 5569
 5570	if (eth_type_vlan(skb->protocol)) {
 5571		skb = skb_vlan_untag(skb);
 5572		if (unlikely(!skb))
 5573			goto out;
 5574	}
 5575
 5576	if (skb_skip_tc_classify(skb))
 5577		goto skip_classify;
 5578
 5579	if (pfmemalloc)
 5580		goto skip_taps;
 5581
 5582	list_for_each_entry_rcu(ptype, &net_hotdata.ptype_all, list) {
 5583		if (pt_prev)
 5584			ret = deliver_skb(skb, pt_prev, orig_dev);
 5585		pt_prev = ptype;
 5586	}
 5587
 5588	list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) {
 5589		if (pt_prev)
 5590			ret = deliver_skb(skb, pt_prev, orig_dev);
 5591		pt_prev = ptype;
 5592	}
 5593
 5594skip_taps:
 5595#ifdef CONFIG_NET_INGRESS
 5596	if (static_branch_unlikely(&ingress_needed_key)) {
 5597		bool another = false;
 5598
 5599		nf_skip_egress(skb, true);
 5600		skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev,
 5601					 &another);
 5602		if (another)
 5603			goto another_round;
 5604		if (!skb)
 5605			goto out;
 5606
 5607		nf_skip_egress(skb, false);
 5608		if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0)
 5609			goto out;
 5610	}
 5611#endif
 5612	skb_reset_redirect(skb);
 5613skip_classify:
 5614	if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
 5615		goto drop;
 5616
 5617	if (skb_vlan_tag_present(skb)) {
 5618		if (pt_prev) {
 5619			ret = deliver_skb(skb, pt_prev, orig_dev);
 5620			pt_prev = NULL;
 
 5621		}
 5622		if (vlan_do_receive(&skb))
 5623			goto another_round;
 5624		else if (unlikely(!skb))
 5625			goto out;
 5626	}
 5627
 
 
 
 
 
 
 
 5628	rx_handler = rcu_dereference(skb->dev->rx_handler);
 5629	if (rx_handler) {
 5630		if (pt_prev) {
 5631			ret = deliver_skb(skb, pt_prev, orig_dev);
 5632			pt_prev = NULL;
 5633		}
 5634		switch (rx_handler(&skb)) {
 5635		case RX_HANDLER_CONSUMED:
 5636			ret = NET_RX_SUCCESS;
 5637			goto out;
 5638		case RX_HANDLER_ANOTHER:
 5639			goto another_round;
 5640		case RX_HANDLER_EXACT:
 5641			deliver_exact = true;
 5642			break;
 5643		case RX_HANDLER_PASS:
 5644			break;
 5645		default:
 5646			BUG();
 5647		}
 5648	}
 5649
 5650	if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) {
 5651check_vlan_id:
 5652		if (skb_vlan_tag_get_id(skb)) {
 5653			/* Vlan id is non 0 and vlan_do_receive() above couldn't
 5654			 * find vlan device.
 5655			 */
 5656			skb->pkt_type = PACKET_OTHERHOST;
 5657		} else if (eth_type_vlan(skb->protocol)) {
 5658			/* Outer header is 802.1P with vlan 0, inner header is
 5659			 * 802.1Q or 802.1AD and vlan_do_receive() above could
 5660			 * not find vlan dev for vlan id 0.
 5661			 */
 5662			__vlan_hwaccel_clear_tag(skb);
 5663			skb = skb_vlan_untag(skb);
 5664			if (unlikely(!skb))
 5665				goto out;
 5666			if (vlan_do_receive(&skb))
 5667				/* After stripping off 802.1P header with vlan 0
 5668				 * vlan dev is found for inner header.
 5669				 */
 5670				goto another_round;
 5671			else if (unlikely(!skb))
 5672				goto out;
 5673			else
 5674				/* We have stripped outer 802.1P vlan 0 header.
 5675				 * But could not find vlan dev.
 5676				 * check again for vlan id to set OTHERHOST.
 5677				 */
 5678				goto check_vlan_id;
 5679		}
 5680		/* Note: we might in the future use prio bits
 5681		 * and set skb->priority like in vlan_do_receive()
 5682		 * For the time being, just ignore Priority Code Point
 5683		 */
 5684		__vlan_hwaccel_clear_tag(skb);
 5685	}
 5686
 5687	type = skb->protocol;
 5688
 5689	/* deliver only exact match when indicated */
 5690	if (likely(!deliver_exact)) {
 5691		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
 5692				       &ptype_base[ntohs(type) &
 5693						   PTYPE_HASH_MASK]);
 5694	}
 5695
 5696	deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
 5697			       &orig_dev->ptype_specific);
 5698
 5699	if (unlikely(skb->dev != orig_dev)) {
 5700		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
 5701				       &skb->dev->ptype_specific);
 
 
 
 
 5702	}
 5703
 5704	if (pt_prev) {
 5705		if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC)))
 5706			goto drop;
 5707		*ppt_prev = pt_prev;
 5708	} else {
 5709drop:
 5710		if (!deliver_exact)
 5711			dev_core_stats_rx_dropped_inc(skb->dev);
 5712		else
 5713			dev_core_stats_rx_nohandler_inc(skb->dev);
 5714		kfree_skb_reason(skb, SKB_DROP_REASON_UNHANDLED_PROTO);
 5715		/* Jamal, now you will not able to escape explaining
 5716		 * me how you were going to use this. :-)
 5717		 */
 5718		ret = NET_RX_DROP;
 5719	}
 5720
 5721out:
 5722	/* The invariant here is that if *ppt_prev is not NULL
 5723	 * then skb should also be non-NULL.
 5724	 *
 5725	 * Apparently *ppt_prev assignment above holds this invariant due to
 5726	 * skb dereferencing near it.
 5727	 */
 5728	*pskb = skb;
 5729	return ret;
 5730}
 5731
 5732static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc)
 5733{
 5734	struct net_device *orig_dev = skb->dev;
 5735	struct packet_type *pt_prev = NULL;
 5736	int ret;
 5737
 5738	ret = __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev);
 5739	if (pt_prev)
 5740		ret = INDIRECT_CALL_INET(pt_prev->func, ipv6_rcv, ip_rcv, skb,
 5741					 skb->dev, pt_prev, orig_dev);
 5742	return ret;
 5743}
 5744
 5745/**
 5746 *	netif_receive_skb_core - special purpose version of netif_receive_skb
 5747 *	@skb: buffer to process
 5748 *
 5749 *	More direct receive version of netif_receive_skb().  It should
 5750 *	only be used by callers that have a need to skip RPS and Generic XDP.
 5751 *	Caller must also take care of handling if ``(page_is_)pfmemalloc``.
 5752 *
 5753 *	This function may only be called from softirq context and interrupts
 5754 *	should be enabled.
 5755 *
 5756 *	Return values (usually ignored):
 5757 *	NET_RX_SUCCESS: no congestion
 5758 *	NET_RX_DROP: packet was dropped
 5759 */
 5760int netif_receive_skb_core(struct sk_buff *skb)
 5761{
 5762	int ret;
 
 5763
 5764	rcu_read_lock();
 5765	ret = __netif_receive_skb_one_core(skb, false);
 5766	rcu_read_unlock();
 5767
 5768	return ret;
 5769}
 5770EXPORT_SYMBOL(netif_receive_skb_core);
 
 5771
 5772static inline void __netif_receive_skb_list_ptype(struct list_head *head,
 5773						  struct packet_type *pt_prev,
 5774						  struct net_device *orig_dev)
 5775{
 5776	struct sk_buff *skb, *next;
 5777
 5778	if (!pt_prev)
 5779		return;
 5780	if (list_empty(head))
 5781		return;
 5782	if (pt_prev->list_func != NULL)
 5783		INDIRECT_CALL_INET(pt_prev->list_func, ipv6_list_rcv,
 5784				   ip_list_rcv, head, pt_prev, orig_dev);
 5785	else
 5786		list_for_each_entry_safe(skb, next, head, list) {
 5787			skb_list_del_init(skb);
 5788			pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
 5789		}
 
 
 
 
 
 
 5790}
 
 5791
 5792static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc)
 5793{
 5794	/* Fast-path assumptions:
 5795	 * - There is no RX handler.
 5796	 * - Only one packet_type matches.
 5797	 * If either of these fails, we will end up doing some per-packet
 5798	 * processing in-line, then handling the 'last ptype' for the whole
 5799	 * sublist.  This can't cause out-of-order delivery to any single ptype,
 5800	 * because the 'last ptype' must be constant across the sublist, and all
 5801	 * other ptypes are handled per-packet.
 5802	 */
 5803	/* Current (common) ptype of sublist */
 5804	struct packet_type *pt_curr = NULL;
 5805	/* Current (common) orig_dev of sublist */
 5806	struct net_device *od_curr = NULL;
 5807	struct sk_buff *skb, *next;
 5808	LIST_HEAD(sublist);
 5809
 5810	list_for_each_entry_safe(skb, next, head, list) {
 5811		struct net_device *orig_dev = skb->dev;
 5812		struct packet_type *pt_prev = NULL;
 5813
 5814		skb_list_del_init(skb);
 5815		__netif_receive_skb_core(&skb, pfmemalloc, &pt_prev);
 5816		if (!pt_prev)
 5817			continue;
 5818		if (pt_curr != pt_prev || od_curr != orig_dev) {
 5819			/* dispatch old sublist */
 5820			__netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr);
 5821			/* start new sublist */
 5822			INIT_LIST_HEAD(&sublist);
 5823			pt_curr = pt_prev;
 5824			od_curr = orig_dev;
 5825		}
 5826		list_add_tail(&skb->list, &sublist);
 5827	}
 
 5828
 5829	/* dispatch final sublist */
 5830	__netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr);
 
 
 
 
 
 5831}
 5832
 5833static int __netif_receive_skb(struct sk_buff *skb)
 5834{
 5835	int ret;
 
 
 
 5836
 5837	if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
 5838		unsigned int noreclaim_flag;
 
 
 5839
 5840		/*
 5841		 * PFMEMALLOC skbs are special, they should
 5842		 * - be delivered to SOCK_MEMALLOC sockets only
 5843		 * - stay away from userspace
 5844		 * - have bounded memory usage
 5845		 *
 5846		 * Use PF_MEMALLOC as this saves us from propagating the allocation
 5847		 * context down to all allocation sites.
 5848		 */
 5849		noreclaim_flag = memalloc_noreclaim_save();
 5850		ret = __netif_receive_skb_one_core(skb, true);
 5851		memalloc_noreclaim_restore(noreclaim_flag);
 5852	} else
 5853		ret = __netif_receive_skb_one_core(skb, false);
 5854
 5855	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 5856}
 5857
 5858static void __netif_receive_skb_list(struct list_head *head)
 5859{
 5860	unsigned long noreclaim_flag = 0;
 5861	struct sk_buff *skb, *next;
 5862	bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */
 5863
 5864	list_for_each_entry_safe(skb, next, head, list) {
 5865		if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) {
 5866			struct list_head sublist;
 5867
 5868			/* Handle the previous sublist */
 5869			list_cut_before(&sublist, head, &skb->list);
 5870			if (!list_empty(&sublist))
 5871				__netif_receive_skb_list_core(&sublist, pfmemalloc);
 5872			pfmemalloc = !pfmemalloc;
 5873			/* See comments in __netif_receive_skb */
 5874			if (pfmemalloc)
 5875				noreclaim_flag = memalloc_noreclaim_save();
 5876			else
 5877				memalloc_noreclaim_restore(noreclaim_flag);
 5878		}
 5879	}
 5880	/* Handle the remaining sublist */
 5881	if (!list_empty(head))
 5882		__netif_receive_skb_list_core(head, pfmemalloc);
 5883	/* Restore pflags */
 5884	if (pfmemalloc)
 5885		memalloc_noreclaim_restore(noreclaim_flag);
 5886}
 
 5887
 5888static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp)
 5889{
 5890	struct bpf_prog *old = rtnl_dereference(dev->xdp_prog);
 5891	struct bpf_prog *new = xdp->prog;
 5892	int ret = 0;
 
 
 
 
 5893
 5894	switch (xdp->command) {
 5895	case XDP_SETUP_PROG:
 5896		rcu_assign_pointer(dev->xdp_prog, new);
 5897		if (old)
 5898			bpf_prog_put(old);
 5899
 5900		if (old && !new) {
 5901			static_branch_dec(&generic_xdp_needed_key);
 5902		} else if (new && !old) {
 5903			static_branch_inc(&generic_xdp_needed_key);
 5904			dev_disable_lro(dev);
 5905			dev_disable_gro_hw(dev);
 5906		}
 5907		break;
 5908
 5909	default:
 5910		ret = -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 5911		break;
 5912	}
 
 5913
 5914	return ret;
 5915}
 5916
 5917static int netif_receive_skb_internal(struct sk_buff *skb)
 5918{
 5919	int ret;
 5920
 5921	net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue), skb);
 
 5922
 5923	if (skb_defer_rx_timestamp(skb))
 5924		return NET_RX_SUCCESS;
 
 
 
 5925
 5926	rcu_read_lock();
 5927#ifdef CONFIG_RPS
 5928	if (static_branch_unlikely(&rps_needed)) {
 5929		struct rps_dev_flow voidflow, *rflow = &voidflow;
 5930		int cpu = get_rps_cpu(skb->dev, skb, &rflow);
 5931
 5932		if (cpu >= 0) {
 5933			ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
 5934			rcu_read_unlock();
 5935			return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 5936		}
 5937	}
 5938#endif
 5939	ret = __netif_receive_skb(skb);
 5940	rcu_read_unlock();
 5941	return ret;
 
 
 
 
 5942}
 
 5943
 5944void netif_receive_skb_list_internal(struct list_head *head)
 
 5945{
 5946	struct sk_buff *skb, *next;
 5947	LIST_HEAD(sublist);
 5948
 5949	list_for_each_entry_safe(skb, next, head, list) {
 5950		net_timestamp_check(READ_ONCE(net_hotdata.tstamp_prequeue),
 5951				    skb);
 5952		skb_list_del_init(skb);
 5953		if (!skb_defer_rx_timestamp(skb))
 5954			list_add_tail(&skb->list, &sublist);
 5955	}
 5956	list_splice_init(&sublist, head);
 5957
 5958	rcu_read_lock();
 5959#ifdef CONFIG_RPS
 5960	if (static_branch_unlikely(&rps_needed)) {
 5961		list_for_each_entry_safe(skb, next, head, list) {
 5962			struct rps_dev_flow voidflow, *rflow = &voidflow;
 5963			int cpu = get_rps_cpu(skb->dev, skb, &rflow);
 5964
 5965			if (cpu >= 0) {
 5966				/* Will be handled, remove from list */
 5967				skb_list_del_init(skb);
 5968				enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
 5969			}
 5970		}
 5971	}
 5972#endif
 5973	__netif_receive_skb_list(head);
 5974	rcu_read_unlock();
 5975}
 5976
 5977/**
 5978 *	netif_receive_skb - process receive buffer from network
 5979 *	@skb: buffer to process
 5980 *
 5981 *	netif_receive_skb() is the main receive data processing function.
 5982 *	It always succeeds. The buffer may be dropped during processing
 5983 *	for congestion control or by the protocol layers.
 5984 *
 5985 *	This function may only be called from softirq context and interrupts
 5986 *	should be enabled.
 5987 *
 5988 *	Return values (usually ignored):
 5989 *	NET_RX_SUCCESS: no congestion
 5990 *	NET_RX_DROP: packet was dropped
 5991 */
 5992int netif_receive_skb(struct sk_buff *skb)
 5993{
 5994	int ret;
 
 
 
 
 5995
 5996	trace_netif_receive_skb_entry(skb);
 
 
 
 5997
 5998	ret = netif_receive_skb_internal(skb);
 5999	trace_netif_receive_skb_exit(ret);
 
 
 6000
 6001	return ret;
 6002}
 6003EXPORT_SYMBOL(netif_receive_skb);
 6004
 6005/**
 6006 *	netif_receive_skb_list - process many receive buffers from network
 6007 *	@head: list of skbs to process.
 6008 *
 6009 *	Since return value of netif_receive_skb() is normally ignored, and
 6010 *	wouldn't be meaningful for a list, this function returns void.
 6011 *
 6012 *	This function may only be called from softirq context and interrupts
 6013 *	should be enabled.
 6014 */
 6015void netif_receive_skb_list(struct list_head *head)
 6016{
 6017	struct sk_buff *skb;
 
 
 6018
 6019	if (list_empty(head))
 6020		return;
 6021	if (trace_netif_receive_skb_list_entry_enabled()) {
 6022		list_for_each_entry(skb, head, list)
 6023			trace_netif_receive_skb_list_entry(skb);
 
 6024	}
 6025	netif_receive_skb_list_internal(head);
 6026	trace_netif_receive_skb_list_exit(0);
 6027}
 6028EXPORT_SYMBOL(netif_receive_skb_list);
 
 
 
 
 6029
 6030static DEFINE_PER_CPU(struct work_struct, flush_works);
 
 
 6031
 6032/* Network device is going away, flush any packets still pending */
 6033static void flush_backlog(struct work_struct *work)
 6034{
 6035	struct sk_buff *skb, *tmp;
 6036	struct softnet_data *sd;
 
 
 
 6037
 6038	local_bh_disable();
 6039	sd = this_cpu_ptr(&softnet_data);
 6040
 6041	backlog_lock_irq_disable(sd);
 6042	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
 6043		if (skb->dev->reg_state == NETREG_UNREGISTERING) {
 6044			__skb_unlink(skb, &sd->input_pkt_queue);
 6045			dev_kfree_skb_irq(skb);
 6046			rps_input_queue_head_incr(sd);
 6047		}
 6048	}
 6049	backlog_unlock_irq_enable(sd);
 6050
 6051	local_lock_nested_bh(&softnet_data.process_queue_bh_lock);
 6052	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
 6053		if (skb->dev->reg_state == NETREG_UNREGISTERING) {
 6054			__skb_unlink(skb, &sd->process_queue);
 6055			kfree_skb(skb);
 6056			rps_input_queue_head_incr(sd);
 6057		}
 6058	}
 6059	local_unlock_nested_bh(&softnet_data.process_queue_bh_lock);
 6060	local_bh_enable();
 6061}
 
 6062
 6063static bool flush_required(int cpu)
 
 6064{
 6065#if IS_ENABLED(CONFIG_RPS)
 6066	struct softnet_data *sd = &per_cpu(softnet_data, cpu);
 6067	bool do_flush;
 
 6068
 6069	backlog_lock_irq_disable(sd);
 
 
 
 
 6070
 6071	/* as insertion into process_queue happens with the rps lock held,
 6072	 * process_queue access may race only with dequeue
 6073	 */
 6074	do_flush = !skb_queue_empty(&sd->input_pkt_queue) ||
 6075		   !skb_queue_empty_lockless(&sd->process_queue);
 6076	backlog_unlock_irq_enable(sd);
 6077
 6078	return do_flush;
 6079#endif
 6080	/* without RPS we can't safely check input_pkt_queue: during a
 6081	 * concurrent remote skb_queue_splice() we can detect as empty both
 6082	 * input_pkt_queue and process_queue even if the latter could end-up
 6083	 * containing a lot of packets.
 6084	 */
 6085	return true;
 6086}
 
 6087
 6088static void flush_all_backlogs(void)
 6089{
 6090	static cpumask_t flush_cpus;
 6091	unsigned int cpu;
 
 
 6092
 6093	/* since we are under rtnl lock protection we can use static data
 6094	 * for the cpumask and avoid allocating on stack the possibly
 6095	 * large mask
 6096	 */
 6097	ASSERT_RTNL();
 6098
 6099	cpus_read_lock();
 
 6100
 6101	cpumask_clear(&flush_cpus);
 6102	for_each_online_cpu(cpu) {
 6103		if (flush_required(cpu)) {
 6104			queue_work_on(cpu, system_highpri_wq,
 6105				      per_cpu_ptr(&flush_works, cpu));
 6106			cpumask_set_cpu(cpu, &flush_cpus);
 
 
 
 6107		}
 6108	}
 6109
 6110	/* we can have in flight packet[s] on the cpus we are not flushing,
 6111	 * synchronize_net() in unregister_netdevice_many() will take care of
 6112	 * them
 
 
 6113	 */
 6114	for_each_cpu(cpu, &flush_cpus)
 6115		flush_work(per_cpu_ptr(&flush_works, cpu));
 6116
 6117	cpus_read_unlock();
 
 6118}
 
 6119
 6120static void net_rps_send_ipi(struct softnet_data *remsd)
 6121{
 6122#ifdef CONFIG_RPS
 6123	while (remsd) {
 6124		struct softnet_data *next = remsd->rps_ipi_next;
 6125
 6126		if (cpu_online(remsd->cpu))
 6127			smp_call_function_single_async(remsd->cpu, &remsd->csd);
 6128		remsd = next;
 6129	}
 6130#endif
 6131}
 
 6132
 6133/*
 6134 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
 6135 * Note: called with local irq disabled, but exits with local irq enabled.
 6136 */
 6137static void net_rps_action_and_irq_enable(struct softnet_data *sd)
 6138{
 6139#ifdef CONFIG_RPS
 6140	struct softnet_data *remsd = sd->rps_ipi_list;
 6141
 6142	if (!use_backlog_threads() && remsd) {
 6143		sd->rps_ipi_list = NULL;
 6144
 6145		local_irq_enable();
 6146
 6147		/* Send pending IPI's to kick RPS processing on remote cpus. */
 6148		net_rps_send_ipi(remsd);
 
 
 
 
 
 
 
 6149	} else
 6150#endif
 6151		local_irq_enable();
 6152}
 6153
 6154static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
 6155{
 6156#ifdef CONFIG_RPS
 6157	return !use_backlog_threads() && sd->rps_ipi_list;
 6158#else
 6159	return false;
 6160#endif
 6161}
 6162
 6163static int process_backlog(struct napi_struct *napi, int quota)
 6164{
 6165	struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
 6166	bool again = true;
 6167	int work = 0;
 
 6168
 
 6169	/* Check if we have pending ipi, its better to send them now,
 6170	 * not waiting net_rx_action() end.
 6171	 */
 6172	if (sd_has_rps_ipi_waiting(sd)) {
 6173		local_irq_disable();
 6174		net_rps_action_and_irq_enable(sd);
 6175	}
 6176
 6177	napi->weight = READ_ONCE(net_hotdata.dev_rx_weight);
 6178	while (again) {
 
 6179		struct sk_buff *skb;
 
 6180
 6181		local_lock_nested_bh(&softnet_data.process_queue_bh_lock);
 6182		while ((skb = __skb_dequeue(&sd->process_queue))) {
 6183			local_unlock_nested_bh(&softnet_data.process_queue_bh_lock);
 6184			rcu_read_lock();
 6185			__netif_receive_skb(skb);
 6186			rcu_read_unlock();
 
 6187			if (++work >= quota) {
 6188				rps_input_queue_head_add(sd, work);
 6189				return work;
 6190			}
 6191
 6192			local_lock_nested_bh(&softnet_data.process_queue_bh_lock);
 6193		}
 6194		local_unlock_nested_bh(&softnet_data.process_queue_bh_lock);
 6195
 6196		backlog_lock_irq_disable(sd);
 6197		if (skb_queue_empty(&sd->input_pkt_queue)) {
 
 
 
 
 
 6198			/*
 6199			 * Inline a custom version of __napi_complete().
 6200			 * only current cpu owns and manipulates this napi,
 6201			 * and NAPI_STATE_SCHED is the only possible flag set
 6202			 * on backlog.
 6203			 * We can use a plain write instead of clear_bit(),
 6204			 * and we dont need an smp_mb() memory barrier.
 6205			 */
 6206			napi->state &= NAPIF_STATE_THREADED;
 6207			again = false;
 6208		} else {
 6209			local_lock_nested_bh(&softnet_data.process_queue_bh_lock);
 6210			skb_queue_splice_tail_init(&sd->input_pkt_queue,
 6211						   &sd->process_queue);
 6212			local_unlock_nested_bh(&softnet_data.process_queue_bh_lock);
 6213		}
 6214		backlog_unlock_irq_enable(sd);
 6215	}
 
 6216
 6217	if (work)
 6218		rps_input_queue_head_add(sd, work);
 6219	return work;
 6220}
 6221
 6222/**
 6223 * __napi_schedule - schedule for receive
 6224 * @n: entry to schedule
 6225 *
 6226 * The entry's receive function will be scheduled to run.
 6227 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
 6228 */
 6229void __napi_schedule(struct napi_struct *n)
 6230{
 6231	unsigned long flags;
 6232
 6233	local_irq_save(flags);
 6234	____napi_schedule(this_cpu_ptr(&softnet_data), n);
 6235	local_irq_restore(flags);
 6236}
 6237EXPORT_SYMBOL(__napi_schedule);
 6238
 6239/**
 6240 *	napi_schedule_prep - check if napi can be scheduled
 6241 *	@n: napi context
 6242 *
 6243 * Test if NAPI routine is already running, and if not mark
 6244 * it as running.  This is used as a condition variable to
 6245 * insure only one NAPI poll instance runs.  We also make
 6246 * sure there is no pending NAPI disable.
 6247 */
 6248bool napi_schedule_prep(struct napi_struct *n)
 6249{
 6250	unsigned long new, val = READ_ONCE(n->state);
 6251
 6252	do {
 6253		if (unlikely(val & NAPIF_STATE_DISABLE))
 6254			return false;
 6255		new = val | NAPIF_STATE_SCHED;
 6256
 6257		/* Sets STATE_MISSED bit if STATE_SCHED was already set
 6258		 * This was suggested by Alexander Duyck, as compiler
 6259		 * emits better code than :
 6260		 * if (val & NAPIF_STATE_SCHED)
 6261		 *     new |= NAPIF_STATE_MISSED;
 6262		 */
 6263		new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED *
 6264						   NAPIF_STATE_MISSED;
 6265	} while (!try_cmpxchg(&n->state, &val, new));
 6266
 6267	return !(val & NAPIF_STATE_SCHED);
 6268}
 6269EXPORT_SYMBOL(napi_schedule_prep);
 6270
 6271/**
 6272 * __napi_schedule_irqoff - schedule for receive
 6273 * @n: entry to schedule
 6274 *
 6275 * Variant of __napi_schedule() assuming hard irqs are masked.
 6276 *
 6277 * On PREEMPT_RT enabled kernels this maps to __napi_schedule()
 6278 * because the interrupt disabled assumption might not be true
 6279 * due to force-threaded interrupts and spinlock substitution.
 6280 */
 6281void __napi_schedule_irqoff(struct napi_struct *n)
 6282{
 6283	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
 6284		____napi_schedule(this_cpu_ptr(&softnet_data), n);
 6285	else
 6286		__napi_schedule(n);
 6287}
 6288EXPORT_SYMBOL(__napi_schedule_irqoff);
 6289
 6290bool napi_complete_done(struct napi_struct *n, int work_done)
 6291{
 6292	unsigned long flags, val, new, timeout = 0;
 6293	bool ret = true;
 6294
 6295	/*
 6296	 * 1) Don't let napi dequeue from the cpu poll list
 6297	 *    just in case its running on a different cpu.
 6298	 * 2) If we are busy polling, do nothing here, we have
 6299	 *    the guarantee we will be called later.
 6300	 */
 6301	if (unlikely(n->state & (NAPIF_STATE_NPSVC |
 6302				 NAPIF_STATE_IN_BUSY_POLL)))
 6303		return false;
 6304
 6305	if (work_done) {
 6306		if (n->gro_bitmask)
 6307			timeout = napi_get_gro_flush_timeout(n);
 6308		n->defer_hard_irqs_count = napi_get_defer_hard_irqs(n);
 6309	}
 6310	if (n->defer_hard_irqs_count > 0) {
 6311		n->defer_hard_irqs_count--;
 6312		timeout = napi_get_gro_flush_timeout(n);
 6313		if (timeout)
 6314			ret = false;
 6315	}
 6316	if (n->gro_bitmask) {
 6317		/* When the NAPI instance uses a timeout and keeps postponing
 6318		 * it, we need to bound somehow the time packets are kept in
 6319		 * the GRO layer
 6320		 */
 6321		napi_gro_flush(n, !!timeout);
 6322	}
 6323
 6324	gro_normal_list(n);
 6325
 6326	if (unlikely(!list_empty(&n->poll_list))) {
 6327		/* If n->poll_list is not empty, we need to mask irqs */
 6328		local_irq_save(flags);
 6329		list_del_init(&n->poll_list);
 6330		local_irq_restore(flags);
 6331	}
 6332	WRITE_ONCE(n->list_owner, -1);
 6333
 6334	val = READ_ONCE(n->state);
 6335	do {
 6336		WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED));
 6337
 6338		new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED |
 6339			      NAPIF_STATE_SCHED_THREADED |
 6340			      NAPIF_STATE_PREFER_BUSY_POLL);
 6341
 6342		/* If STATE_MISSED was set, leave STATE_SCHED set,
 6343		 * because we will call napi->poll() one more time.
 6344		 * This C code was suggested by Alexander Duyck to help gcc.
 6345		 */
 6346		new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED *
 6347						    NAPIF_STATE_SCHED;
 6348	} while (!try_cmpxchg(&n->state, &val, new));
 6349
 6350	if (unlikely(val & NAPIF_STATE_MISSED)) {
 6351		__napi_schedule(n);
 6352		return false;
 6353	}
 6354
 6355	if (timeout)
 6356		hrtimer_start(&n->timer, ns_to_ktime(timeout),
 6357			      HRTIMER_MODE_REL_PINNED);
 6358	return ret;
 6359}
 6360EXPORT_SYMBOL(napi_complete_done);
 6361
 6362static void skb_defer_free_flush(struct softnet_data *sd)
 6363{
 6364	struct sk_buff *skb, *next;
 6365
 6366	/* Paired with WRITE_ONCE() in skb_attempt_defer_free() */
 6367	if (!READ_ONCE(sd->defer_list))
 6368		return;
 6369
 6370	spin_lock(&sd->defer_lock);
 6371	skb = sd->defer_list;
 6372	sd->defer_list = NULL;
 6373	sd->defer_count = 0;
 6374	spin_unlock(&sd->defer_lock);
 6375
 6376	while (skb != NULL) {
 6377		next = skb->next;
 6378		napi_consume_skb(skb, 1);
 6379		skb = next;
 6380	}
 6381}
 6382
 6383#if defined(CONFIG_NET_RX_BUSY_POLL)
 6384
 6385static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule)
 6386{
 6387	if (!skip_schedule) {
 6388		gro_normal_list(napi);
 6389		__napi_schedule(napi);
 6390		return;
 6391	}
 6392
 6393	if (napi->gro_bitmask) {
 6394		/* flush too old packets
 6395		 * If HZ < 1000, flush all packets.
 6396		 */
 6397		napi_gro_flush(napi, HZ >= 1000);
 6398	}
 6399
 6400	gro_normal_list(napi);
 6401	clear_bit(NAPI_STATE_SCHED, &napi->state);
 6402}
 6403
 6404enum {
 6405	NAPI_F_PREFER_BUSY_POLL	= 1,
 6406	NAPI_F_END_ON_RESCHED	= 2,
 6407};
 6408
 6409static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock,
 6410			   unsigned flags, u16 budget)
 6411{
 6412	struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx;
 6413	bool skip_schedule = false;
 6414	unsigned long timeout;
 6415	int rc;
 6416
 6417	/* Busy polling means there is a high chance device driver hard irq
 6418	 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was
 6419	 * set in napi_schedule_prep().
 6420	 * Since we are about to call napi->poll() once more, we can safely
 6421	 * clear NAPI_STATE_MISSED.
 6422	 *
 6423	 * Note: x86 could use a single "lock and ..." instruction
 6424	 * to perform these two clear_bit()
 6425	 */
 6426	clear_bit(NAPI_STATE_MISSED, &napi->state);
 6427	clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state);
 6428
 6429	local_bh_disable();
 6430	bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx);
 6431
 6432	if (flags & NAPI_F_PREFER_BUSY_POLL) {
 6433		napi->defer_hard_irqs_count = napi_get_defer_hard_irqs(napi);
 6434		timeout = napi_get_gro_flush_timeout(napi);
 6435		if (napi->defer_hard_irqs_count && timeout) {
 6436			hrtimer_start(&napi->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINNED);
 6437			skip_schedule = true;
 6438		}
 6439	}
 6440
 6441	/* All we really want here is to re-enable device interrupts.
 6442	 * Ideally, a new ndo_busy_poll_stop() could avoid another round.
 6443	 */
 6444	rc = napi->poll(napi, budget);
 6445	/* We can't gro_normal_list() here, because napi->poll() might have
 6446	 * rearmed the napi (napi_complete_done()) in which case it could
 6447	 * already be running on another CPU.
 6448	 */
 6449	trace_napi_poll(napi, rc, budget);
 6450	netpoll_poll_unlock(have_poll_lock);
 6451	if (rc == budget)
 6452		__busy_poll_stop(napi, skip_schedule);
 6453	bpf_net_ctx_clear(bpf_net_ctx);
 6454	local_bh_enable();
 6455}
 6456
 6457static void __napi_busy_loop(unsigned int napi_id,
 6458		      bool (*loop_end)(void *, unsigned long),
 6459		      void *loop_end_arg, unsigned flags, u16 budget)
 6460{
 6461	unsigned long start_time = loop_end ? busy_loop_current_time() : 0;
 6462	int (*napi_poll)(struct napi_struct *napi, int budget);
 6463	struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx;
 6464	void *have_poll_lock = NULL;
 6465	struct napi_struct *napi;
 6466
 6467	WARN_ON_ONCE(!rcu_read_lock_held());
 6468
 6469restart:
 6470	napi_poll = NULL;
 6471
 6472	napi = napi_by_id(napi_id);
 6473	if (!napi)
 6474		return;
 6475
 6476	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
 6477		preempt_disable();
 6478	for (;;) {
 6479		int work = 0;
 6480
 6481		local_bh_disable();
 6482		bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx);
 6483		if (!napi_poll) {
 6484			unsigned long val = READ_ONCE(napi->state);
 6485
 6486			/* If multiple threads are competing for this napi,
 6487			 * we avoid dirtying napi->state as much as we can.
 6488			 */
 6489			if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED |
 6490				   NAPIF_STATE_IN_BUSY_POLL)) {
 6491				if (flags & NAPI_F_PREFER_BUSY_POLL)
 6492					set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state);
 6493				goto count;
 6494			}
 6495			if (cmpxchg(&napi->state, val,
 6496				    val | NAPIF_STATE_IN_BUSY_POLL |
 6497					  NAPIF_STATE_SCHED) != val) {
 6498				if (flags & NAPI_F_PREFER_BUSY_POLL)
 6499					set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state);
 6500				goto count;
 6501			}
 6502			have_poll_lock = netpoll_poll_lock(napi);
 6503			napi_poll = napi->poll;
 6504		}
 6505		work = napi_poll(napi, budget);
 6506		trace_napi_poll(napi, work, budget);
 6507		gro_normal_list(napi);
 6508count:
 6509		if (work > 0)
 6510			__NET_ADD_STATS(dev_net(napi->dev),
 6511					LINUX_MIB_BUSYPOLLRXPACKETS, work);
 6512		skb_defer_free_flush(this_cpu_ptr(&softnet_data));
 6513		bpf_net_ctx_clear(bpf_net_ctx);
 6514		local_bh_enable();
 6515
 6516		if (!loop_end || loop_end(loop_end_arg, start_time))
 6517			break;
 6518
 6519		if (unlikely(need_resched())) {
 6520			if (flags & NAPI_F_END_ON_RESCHED)
 6521				break;
 6522			if (napi_poll)
 6523				busy_poll_stop(napi, have_poll_lock, flags, budget);
 6524			if (!IS_ENABLED(CONFIG_PREEMPT_RT))
 6525				preempt_enable();
 6526			rcu_read_unlock();
 6527			cond_resched();
 6528			rcu_read_lock();
 6529			if (loop_end(loop_end_arg, start_time))
 6530				return;
 6531			goto restart;
 6532		}
 6533		cpu_relax();
 6534	}
 6535	if (napi_poll)
 6536		busy_poll_stop(napi, have_poll_lock, flags, budget);
 6537	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
 6538		preempt_enable();
 6539}
 6540
 6541void napi_busy_loop_rcu(unsigned int napi_id,
 6542			bool (*loop_end)(void *, unsigned long),
 6543			void *loop_end_arg, bool prefer_busy_poll, u16 budget)
 6544{
 6545	unsigned flags = NAPI_F_END_ON_RESCHED;
 6546
 6547	if (prefer_busy_poll)
 6548		flags |= NAPI_F_PREFER_BUSY_POLL;
 6549
 6550	__napi_busy_loop(napi_id, loop_end, loop_end_arg, flags, budget);
 6551}
 6552
 6553void napi_busy_loop(unsigned int napi_id,
 6554		    bool (*loop_end)(void *, unsigned long),
 6555		    void *loop_end_arg, bool prefer_busy_poll, u16 budget)
 6556{
 6557	unsigned flags = prefer_busy_poll ? NAPI_F_PREFER_BUSY_POLL : 0;
 6558
 6559	rcu_read_lock();
 6560	__napi_busy_loop(napi_id, loop_end, loop_end_arg, flags, budget);
 6561	rcu_read_unlock();
 6562}
 6563EXPORT_SYMBOL(napi_busy_loop);
 6564
 6565void napi_suspend_irqs(unsigned int napi_id)
 6566{
 6567	struct napi_struct *napi;
 6568
 6569	rcu_read_lock();
 6570	napi = napi_by_id(napi_id);
 6571	if (napi) {
 6572		unsigned long timeout = napi_get_irq_suspend_timeout(napi);
 6573
 6574		if (timeout)
 6575			hrtimer_start(&napi->timer, ns_to_ktime(timeout),
 6576				      HRTIMER_MODE_REL_PINNED);
 6577	}
 6578	rcu_read_unlock();
 6579}
 6580
 6581void napi_resume_irqs(unsigned int napi_id)
 6582{
 6583	struct napi_struct *napi;
 6584
 6585	rcu_read_lock();
 6586	napi = napi_by_id(napi_id);
 6587	if (napi) {
 6588		/* If irq_suspend_timeout is set to 0 between the call to
 6589		 * napi_suspend_irqs and now, the original value still
 6590		 * determines the safety timeout as intended and napi_watchdog
 6591		 * will resume irq processing.
 6592		 */
 6593		if (napi_get_irq_suspend_timeout(napi)) {
 6594			local_bh_disable();
 6595			napi_schedule(napi);
 6596			local_bh_enable();
 6597		}
 6598	}
 6599	rcu_read_unlock();
 6600}
 6601
 6602#endif /* CONFIG_NET_RX_BUSY_POLL */
 6603
 6604static void __napi_hash_add_with_id(struct napi_struct *napi,
 6605				    unsigned int napi_id)
 6606{
 6607	WRITE_ONCE(napi->napi_id, napi_id);
 6608	hlist_add_head_rcu(&napi->napi_hash_node,
 6609			   &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
 6610}
 6611
 6612static void napi_hash_add_with_id(struct napi_struct *napi,
 6613				  unsigned int napi_id)
 6614{
 6615	unsigned long flags;
 
 6616
 6617	spin_lock_irqsave(&napi_hash_lock, flags);
 6618	WARN_ON_ONCE(napi_by_id(napi_id));
 6619	__napi_hash_add_with_id(napi, napi_id);
 6620	spin_unlock_irqrestore(&napi_hash_lock, flags);
 6621}
 
 6622
 6623static void napi_hash_add(struct napi_struct *napi)
 6624{
 6625	unsigned long flags;
 6626
 6627	if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state))
 6628		return;
 6629
 6630	spin_lock_irqsave(&napi_hash_lock, flags);
 6631
 6632	/* 0..NR_CPUS range is reserved for sender_cpu use */
 6633	do {
 6634		if (unlikely(++napi_gen_id < MIN_NAPI_ID))
 6635			napi_gen_id = MIN_NAPI_ID;
 6636	} while (napi_by_id(napi_gen_id));
 6637
 6638	__napi_hash_add_with_id(napi, napi_gen_id);
 6639
 6640	spin_unlock_irqrestore(&napi_hash_lock, flags);
 6641}
 6642
 6643/* Warning : caller is responsible to make sure rcu grace period
 6644 * is respected before freeing memory containing @napi
 6645 */
 6646static void napi_hash_del(struct napi_struct *napi)
 6647{
 6648	unsigned long flags;
 6649
 6650	spin_lock_irqsave(&napi_hash_lock, flags);
 6651
 6652	hlist_del_init_rcu(&napi->napi_hash_node);
 6653
 6654	spin_unlock_irqrestore(&napi_hash_lock, flags);
 6655}
 6656
 6657static enum hrtimer_restart napi_watchdog(struct hrtimer *timer)
 6658{
 6659	struct napi_struct *napi;
 6660
 6661	napi = container_of(timer, struct napi_struct, timer);
 6662
 6663	/* Note : we use a relaxed variant of napi_schedule_prep() not setting
 6664	 * NAPI_STATE_MISSED, since we do not react to a device IRQ.
 6665	 */
 6666	if (!napi_disable_pending(napi) &&
 6667	    !test_and_set_bit(NAPI_STATE_SCHED, &napi->state)) {
 6668		clear_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state);
 6669		__napi_schedule_irqoff(napi);
 6670	}
 6671
 6672	return HRTIMER_NORESTART;
 6673}
 6674
 6675static void init_gro_hash(struct napi_struct *napi)
 6676{
 6677	int i;
 6678
 6679	for (i = 0; i < GRO_HASH_BUCKETS; i++) {
 6680		INIT_LIST_HEAD(&napi->gro_hash[i].list);
 6681		napi->gro_hash[i].count = 0;
 6682	}
 6683	napi->gro_bitmask = 0;
 6684}
 6685
 6686int dev_set_threaded(struct net_device *dev, bool threaded)
 6687{
 6688	struct napi_struct *napi;
 6689	int err = 0;
 6690
 6691	if (dev->threaded == threaded)
 6692		return 0;
 6693
 6694	if (threaded) {
 6695		list_for_each_entry(napi, &dev->napi_list, dev_list) {
 6696			if (!napi->thread) {
 6697				err = napi_kthread_create(napi);
 6698				if (err) {
 6699					threaded = false;
 6700					break;
 6701				}
 6702			}
 6703		}
 6704	}
 6705
 6706	WRITE_ONCE(dev->threaded, threaded);
 6707
 6708	/* Make sure kthread is created before THREADED bit
 6709	 * is set.
 6710	 */
 6711	smp_mb__before_atomic();
 6712
 6713	/* Setting/unsetting threaded mode on a napi might not immediately
 6714	 * take effect, if the current napi instance is actively being
 6715	 * polled. In this case, the switch between threaded mode and
 6716	 * softirq mode will happen in the next round of napi_schedule().
 6717	 * This should not cause hiccups/stalls to the live traffic.
 6718	 */
 6719	list_for_each_entry(napi, &dev->napi_list, dev_list)
 6720		assign_bit(NAPI_STATE_THREADED, &napi->state, threaded);
 6721
 6722	return err;
 6723}
 6724EXPORT_SYMBOL(dev_set_threaded);
 6725
 6726/**
 6727 * netif_queue_set_napi - Associate queue with the napi
 6728 * @dev: device to which NAPI and queue belong
 6729 * @queue_index: Index of queue
 6730 * @type: queue type as RX or TX
 6731 * @napi: NAPI context, pass NULL to clear previously set NAPI
 6732 *
 6733 * Set queue with its corresponding napi context. This should be done after
 6734 * registering the NAPI handler for the queue-vector and the queues have been
 6735 * mapped to the corresponding interrupt vector.
 6736 */
 6737void netif_queue_set_napi(struct net_device *dev, unsigned int queue_index,
 6738			  enum netdev_queue_type type, struct napi_struct *napi)
 6739{
 6740	struct netdev_rx_queue *rxq;
 6741	struct netdev_queue *txq;
 6742
 6743	if (WARN_ON_ONCE(napi && !napi->dev))
 6744		return;
 6745	if (dev->reg_state >= NETREG_REGISTERED)
 6746		ASSERT_RTNL();
 6747
 6748	switch (type) {
 6749	case NETDEV_QUEUE_TYPE_RX:
 6750		rxq = __netif_get_rx_queue(dev, queue_index);
 6751		rxq->napi = napi;
 6752		return;
 6753	case NETDEV_QUEUE_TYPE_TX:
 6754		txq = netdev_get_tx_queue(dev, queue_index);
 6755		txq->napi = napi;
 6756		return;
 6757	default:
 6758		return;
 6759	}
 6760}
 6761EXPORT_SYMBOL(netif_queue_set_napi);
 6762
 6763static void napi_restore_config(struct napi_struct *n)
 6764{
 6765	n->defer_hard_irqs = n->config->defer_hard_irqs;
 6766	n->gro_flush_timeout = n->config->gro_flush_timeout;
 6767	n->irq_suspend_timeout = n->config->irq_suspend_timeout;
 6768	/* a NAPI ID might be stored in the config, if so use it. if not, use
 6769	 * napi_hash_add to generate one for us. It will be saved to the config
 6770	 * in napi_disable.
 6771	 */
 6772	if (n->config->napi_id)
 6773		napi_hash_add_with_id(n, n->config->napi_id);
 6774	else
 6775		napi_hash_add(n);
 6776}
 6777
 6778static void napi_save_config(struct napi_struct *n)
 6779{
 6780	n->config->defer_hard_irqs = n->defer_hard_irqs;
 6781	n->config->gro_flush_timeout = n->gro_flush_timeout;
 6782	n->config->irq_suspend_timeout = n->irq_suspend_timeout;
 6783	n->config->napi_id = n->napi_id;
 6784	napi_hash_del(n);
 6785}
 
 6786
 6787void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi,
 6788			   int (*poll)(struct napi_struct *, int), int weight)
 6789{
 6790	if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state)))
 6791		return;
 6792
 6793	INIT_LIST_HEAD(&napi->poll_list);
 6794	INIT_HLIST_NODE(&napi->napi_hash_node);
 6795	hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
 6796	napi->timer.function = napi_watchdog;
 6797	init_gro_hash(napi);
 6798	napi->skb = NULL;
 6799	INIT_LIST_HEAD(&napi->rx_list);
 6800	napi->rx_count = 0;
 6801	napi->poll = poll;
 6802	if (weight > NAPI_POLL_WEIGHT)
 6803		netdev_err_once(dev, "%s() called with weight %d\n", __func__,
 6804				weight);
 6805	napi->weight = weight;
 
 6806	napi->dev = dev;
 6807#ifdef CONFIG_NETPOLL
 
 6808	napi->poll_owner = -1;
 6809#endif
 6810	napi->list_owner = -1;
 6811	set_bit(NAPI_STATE_SCHED, &napi->state);
 6812	set_bit(NAPI_STATE_NPSVC, &napi->state);
 6813	list_add_rcu(&napi->dev_list, &dev->napi_list);
 6814
 6815	/* default settings from sysfs are applied to all NAPIs. any per-NAPI
 6816	 * configuration will be loaded in napi_enable
 6817	 */
 6818	napi_set_defer_hard_irqs(napi, READ_ONCE(dev->napi_defer_hard_irqs));
 6819	napi_set_gro_flush_timeout(napi, READ_ONCE(dev->gro_flush_timeout));
 6820
 6821	napi_get_frags_check(napi);
 6822	/* Create kthread for this napi if dev->threaded is set.
 6823	 * Clear dev->threaded if kthread creation failed so that
 6824	 * threaded mode will not be enabled in napi_enable().
 6825	 */
 6826	if (dev->threaded && napi_kthread_create(napi))
 6827		dev->threaded = false;
 6828	netif_napi_set_irq(napi, -1);
 6829}
 6830EXPORT_SYMBOL(netif_napi_add_weight);
 6831
 6832void napi_disable(struct napi_struct *n)
 6833{
 6834	unsigned long val, new;
 6835
 6836	might_sleep();
 6837	set_bit(NAPI_STATE_DISABLE, &n->state);
 6838
 6839	val = READ_ONCE(n->state);
 6840	do {
 6841		while (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) {
 6842			usleep_range(20, 200);
 6843			val = READ_ONCE(n->state);
 6844		}
 6845
 6846		new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC;
 6847		new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL);
 6848	} while (!try_cmpxchg(&n->state, &val, new));
 6849
 6850	hrtimer_cancel(&n->timer);
 6851
 6852	if (n->config)
 6853		napi_save_config(n);
 6854	else
 6855		napi_hash_del(n);
 6856
 6857	clear_bit(NAPI_STATE_DISABLE, &n->state);
 6858}
 6859EXPORT_SYMBOL(napi_disable);
 6860
 6861/**
 6862 *	napi_enable - enable NAPI scheduling
 6863 *	@n: NAPI context
 6864 *
 6865 * Resume NAPI from being scheduled on this context.
 6866 * Must be paired with napi_disable.
 6867 */
 6868void napi_enable(struct napi_struct *n)
 6869{
 6870	unsigned long new, val = READ_ONCE(n->state);
 6871
 6872	if (n->config)
 6873		napi_restore_config(n);
 6874	else
 6875		napi_hash_add(n);
 6876
 6877	do {
 6878		BUG_ON(!test_bit(NAPI_STATE_SCHED, &val));
 6879
 6880		new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC);
 6881		if (n->dev->threaded && n->thread)
 6882			new |= NAPIF_STATE_THREADED;
 6883	} while (!try_cmpxchg(&n->state, &val, new));
 6884}
 6885EXPORT_SYMBOL(napi_enable);
 6886
 6887static void flush_gro_hash(struct napi_struct *napi)
 6888{
 6889	int i;
 6890
 6891	for (i = 0; i < GRO_HASH_BUCKETS; i++) {
 6892		struct sk_buff *skb, *n;
 6893
 6894		list_for_each_entry_safe(skb, n, &napi->gro_hash[i].list, list)
 6895			kfree_skb(skb);
 6896		napi->gro_hash[i].count = 0;
 6897	}
 6898}
 6899
 6900/* Must be called in process context */
 6901void __netif_napi_del(struct napi_struct *napi)
 6902{
 6903	if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state))
 6904		return;
 6905
 6906	if (napi->config) {
 6907		napi->index = -1;
 6908		napi->config = NULL;
 6909	}
 6910
 6911	list_del_rcu(&napi->dev_list);
 6912	napi_free_frags(napi);
 6913
 6914	flush_gro_hash(napi);
 6915	napi->gro_bitmask = 0;
 6916
 6917	if (napi->thread) {
 6918		kthread_stop(napi->thread);
 6919		napi->thread = NULL;
 6920	}
 6921}
 6922EXPORT_SYMBOL(__netif_napi_del);
 6923
 6924static int __napi_poll(struct napi_struct *n, bool *repoll)
 6925{
 6926	int work, weight;
 6927
 6928	weight = n->weight;
 6929
 6930	/* This NAPI_STATE_SCHED test is for avoiding a race
 6931	 * with netpoll's poll_napi().  Only the entity which
 6932	 * obtains the lock and sees NAPI_STATE_SCHED set will
 6933	 * actually make the ->poll() call.  Therefore we avoid
 6934	 * accidentally calling ->poll() when NAPI is not scheduled.
 6935	 */
 6936	work = 0;
 6937	if (napi_is_scheduled(n)) {
 6938		work = n->poll(n, weight);
 6939		trace_napi_poll(n, work, weight);
 6940
 6941		xdp_do_check_flushed(n);
 6942	}
 6943
 6944	if (unlikely(work > weight))
 6945		netdev_err_once(n->dev, "NAPI poll function %pS returned %d, exceeding its budget of %d.\n",
 6946				n->poll, work, weight);
 6947
 6948	if (likely(work < weight))
 6949		return work;
 6950
 6951	/* Drivers must not modify the NAPI state if they
 6952	 * consume the entire weight.  In such cases this code
 6953	 * still "owns" the NAPI instance and therefore can
 6954	 * move the instance around on the list at-will.
 6955	 */
 6956	if (unlikely(napi_disable_pending(n))) {
 6957		napi_complete(n);
 6958		return work;
 6959	}
 6960
 6961	/* The NAPI context has more processing work, but busy-polling
 6962	 * is preferred. Exit early.
 6963	 */
 6964	if (napi_prefer_busy_poll(n)) {
 6965		if (napi_complete_done(n, work)) {
 6966			/* If timeout is not set, we need to make sure
 6967			 * that the NAPI is re-scheduled.
 6968			 */
 6969			napi_schedule(n);
 6970		}
 6971		return work;
 6972	}
 6973
 6974	if (n->gro_bitmask) {
 6975		/* flush too old packets
 6976		 * If HZ < 1000, flush all packets.
 6977		 */
 6978		napi_gro_flush(n, HZ >= 1000);
 6979	}
 6980
 6981	gro_normal_list(n);
 6982
 6983	/* Some drivers may have called napi_schedule
 6984	 * prior to exhausting their budget.
 6985	 */
 6986	if (unlikely(!list_empty(&n->poll_list))) {
 6987		pr_warn_once("%s: Budget exhausted after napi rescheduled\n",
 6988			     n->dev ? n->dev->name : "backlog");
 6989		return work;
 6990	}
 6991
 6992	*repoll = true;
 6993
 6994	return work;
 6995}
 
 6996
 6997static int napi_poll(struct napi_struct *n, struct list_head *repoll)
 6998{
 6999	bool do_repoll = false;
 
 
 7000	void *have;
 7001	int work;
 7002
 7003	list_del_init(&n->poll_list);
 7004
 7005	have = netpoll_poll_lock(n);
 7006
 7007	work = __napi_poll(n, &do_repoll);
 7008
 7009	if (do_repoll)
 7010		list_add_tail(&n->poll_list, repoll);
 7011
 7012	netpoll_poll_unlock(have);
 7013
 7014	return work;
 7015}
 7016
 7017static int napi_thread_wait(struct napi_struct *napi)
 7018{
 7019	set_current_state(TASK_INTERRUPTIBLE);
 7020
 7021	while (!kthread_should_stop()) {
 7022		/* Testing SCHED_THREADED bit here to make sure the current
 7023		 * kthread owns this napi and could poll on this napi.
 7024		 * Testing SCHED bit is not enough because SCHED bit might be
 7025		 * set by some other busy poll thread or by napi_disable().
 7026		 */
 7027		if (test_bit(NAPI_STATE_SCHED_THREADED, &napi->state)) {
 7028			WARN_ON(!list_empty(&napi->poll_list));
 7029			__set_current_state(TASK_RUNNING);
 7030			return 0;
 7031		}
 7032
 7033		schedule();
 7034		set_current_state(TASK_INTERRUPTIBLE);
 7035	}
 7036	__set_current_state(TASK_RUNNING);
 7037
 7038	return -1;
 7039}
 7040
 7041static void napi_threaded_poll_loop(struct napi_struct *napi)
 7042{
 7043	struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx;
 7044	struct softnet_data *sd;
 7045	unsigned long last_qs = jiffies;
 7046
 7047	for (;;) {
 7048		bool repoll = false;
 7049		void *have;
 7050
 7051		local_bh_disable();
 7052		bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx);
 7053
 7054		sd = this_cpu_ptr(&softnet_data);
 7055		sd->in_napi_threaded_poll = true;
 7056
 7057		have = netpoll_poll_lock(napi);
 7058		__napi_poll(napi, &repoll);
 7059		netpoll_poll_unlock(have);
 7060
 7061		sd->in_napi_threaded_poll = false;
 7062		barrier();
 7063
 7064		if (sd_has_rps_ipi_waiting(sd)) {
 7065			local_irq_disable();
 7066			net_rps_action_and_irq_enable(sd);
 7067		}
 7068		skb_defer_free_flush(sd);
 7069		bpf_net_ctx_clear(bpf_net_ctx);
 7070		local_bh_enable();
 7071
 7072		if (!repoll)
 7073			break;
 7074
 7075		rcu_softirq_qs_periodic(last_qs);
 7076		cond_resched();
 7077	}
 7078}
 7079
 7080static int napi_threaded_poll(void *data)
 7081{
 7082	struct napi_struct *napi = data;
 7083
 7084	while (!napi_thread_wait(napi))
 7085		napi_threaded_poll_loop(napi);
 7086
 7087	return 0;
 7088}
 7089
 7090static __latent_entropy void net_rx_action(void)
 7091{
 7092	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
 7093	unsigned long time_limit = jiffies +
 7094		usecs_to_jiffies(READ_ONCE(net_hotdata.netdev_budget_usecs));
 7095	struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx;
 7096	int budget = READ_ONCE(net_hotdata.netdev_budget);
 7097	LIST_HEAD(list);
 7098	LIST_HEAD(repoll);
 7099
 7100	bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx);
 7101start:
 7102	sd->in_net_rx_action = true;
 7103	local_irq_disable();
 7104	list_splice_init(&sd->poll_list, &list);
 7105	local_irq_enable();
 7106
 7107	for (;;) {
 7108		struct napi_struct *n;
 
 7109
 7110		skb_defer_free_flush(sd);
 7111
 7112		if (list_empty(&list)) {
 7113			if (list_empty(&repoll)) {
 7114				sd->in_net_rx_action = false;
 7115				barrier();
 7116				/* We need to check if ____napi_schedule()
 7117				 * had refilled poll_list while
 7118				 * sd->in_net_rx_action was true.
 7119				 */
 7120				if (!list_empty(&sd->poll_list))
 7121					goto start;
 7122				if (!sd_has_rps_ipi_waiting(sd))
 7123					goto end;
 7124			}
 7125			break;
 7126		}
 7127
 7128		n = list_first_entry(&list, struct napi_struct, poll_list);
 7129		budget -= napi_poll(n, &repoll);
 7130
 7131		/* If softirq window is exhausted then punt.
 7132		 * Allow this to run for 2 jiffies since which will allow
 7133		 * an average latency of 1.5/HZ.
 7134		 */
 7135		if (unlikely(budget <= 0 ||
 7136			     time_after_eq(jiffies, time_limit))) {
 7137			sd->time_squeeze++;
 7138			break;
 7139		}
 7140	}
 7141
 7142	local_irq_disable();
 7143
 7144	list_splice_tail_init(&sd->poll_list, &list);
 7145	list_splice_tail(&repoll, &list);
 7146	list_splice(&list, &sd->poll_list);
 7147	if (!list_empty(&sd->poll_list))
 7148		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
 7149	else
 7150		sd->in_net_rx_action = false;
 7151
 7152	net_rps_action_and_irq_enable(sd);
 7153end:
 7154	bpf_net_ctx_clear(bpf_net_ctx);
 7155}
 
 
 7156
 7157struct netdev_adjacent {
 7158	struct net_device *dev;
 7159	netdevice_tracker dev_tracker;
 7160
 7161	/* upper master flag, there can only be one master device per list */
 7162	bool master;
 7163
 7164	/* lookup ignore flag */
 7165	bool ignore;
 
 
 
 
 
 
 
 
 
 7166
 7167	/* counter for the number of times this device was added to us */
 7168	u16 ref_nr;
 7169
 7170	/* private field for the users */
 7171	void *private;
 7172
 7173	struct list_head list;
 7174	struct rcu_head rcu;
 7175};
 7176
 7177static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev,
 7178						 struct list_head *adj_list)
 7179{
 7180	struct netdev_adjacent *adj;
 
 
 
 
 
 
 
 
 
 7181
 7182	list_for_each_entry(adj, adj_list, list) {
 7183		if (adj->dev == adj_dev)
 7184			return adj;
 7185	}
 7186	return NULL;
 7187}
 7188
 7189static int ____netdev_has_upper_dev(struct net_device *upper_dev,
 7190				    struct netdev_nested_priv *priv)
 7191{
 7192	struct net_device *dev = (struct net_device *)priv->data;
 7193
 7194	return upper_dev == dev;
 7195}
 7196
 7197/**
 7198 * netdev_has_upper_dev - Check if device is linked to an upper device
 7199 * @dev: device
 7200 * @upper_dev: upper device to check
 7201 *
 7202 * Find out if a device is linked to specified upper device and return true
 7203 * in case it is. Note that this checks only immediate upper device,
 7204 * not through a complete stack of devices. The caller must hold the RTNL lock.
 7205 */
 7206bool netdev_has_upper_dev(struct net_device *dev,
 7207			  struct net_device *upper_dev)
 7208{
 7209	struct netdev_nested_priv priv = {
 7210		.data = (void *)upper_dev,
 7211	};
 7212
 7213	ASSERT_RTNL();
 7214
 7215	return netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev,
 7216					     &priv);
 7217}
 7218EXPORT_SYMBOL(netdev_has_upper_dev);
 7219
 7220/**
 7221 * netdev_has_upper_dev_all_rcu - Check if device is linked to an upper device
 7222 * @dev: device
 7223 * @upper_dev: upper device to check
 7224 *
 7225 * Find out if a device is linked to specified upper device and return true
 7226 * in case it is. Note that this checks the entire upper device chain.
 7227 * The caller must hold rcu lock.
 7228 */
 7229
 7230bool netdev_has_upper_dev_all_rcu(struct net_device *dev,
 7231				  struct net_device *upper_dev)
 7232{
 7233	struct netdev_nested_priv priv = {
 7234		.data = (void *)upper_dev,
 7235	};
 7236
 7237	return !!netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev,
 7238					       &priv);
 
 
 7239}
 7240EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu);
 7241
 7242/**
 7243 * netdev_has_any_upper_dev - Check if device is linked to some device
 7244 * @dev: device
 7245 *
 7246 * Find out if a device is linked to an upper device and return true in case
 7247 * it is. The caller must hold the RTNL lock.
 7248 */
 7249bool netdev_has_any_upper_dev(struct net_device *dev)
 7250{
 7251	ASSERT_RTNL();
 7252
 7253	return !list_empty(&dev->adj_list.upper);
 7254}
 7255EXPORT_SYMBOL(netdev_has_any_upper_dev);
 7256
 7257/**
 7258 * netdev_master_upper_dev_get - Get master upper device
 7259 * @dev: device
 
 7260 *
 7261 * Find a master upper device and return pointer to it or NULL in case
 7262 * it's not there. The caller must hold the RTNL lock.
 
 7263 */
 7264struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
 7265{
 7266	struct netdev_adjacent *upper;
 7267
 7268	ASSERT_RTNL();
 7269
 7270	if (list_empty(&dev->adj_list.upper))
 7271		return NULL;
 7272
 7273	upper = list_first_entry(&dev->adj_list.upper,
 7274				 struct netdev_adjacent, list);
 7275	if (likely(upper->master))
 7276		return upper->dev;
 7277	return NULL;
 7278}
 7279EXPORT_SYMBOL(netdev_master_upper_dev_get);
 7280
 7281static struct net_device *__netdev_master_upper_dev_get(struct net_device *dev)
 7282{
 7283	struct netdev_adjacent *upper;
 7284
 7285	ASSERT_RTNL();
 7286
 7287	if (list_empty(&dev->adj_list.upper))
 7288		return NULL;
 7289
 7290	upper = list_first_entry(&dev->adj_list.upper,
 7291				 struct netdev_adjacent, list);
 7292	if (likely(upper->master) && !upper->ignore)
 7293		return upper->dev;
 7294	return NULL;
 7295}
 7296
 7297/**
 7298 * netdev_has_any_lower_dev - Check if device is linked to some device
 7299 * @dev: device
 7300 *
 7301 * Find out if a device is linked to a lower device and return true in case
 7302 * it is. The caller must hold the RTNL lock.
 7303 */
 7304static bool netdev_has_any_lower_dev(struct net_device *dev)
 7305{
 7306	ASSERT_RTNL();
 7307
 7308	return !list_empty(&dev->adj_list.lower);
 7309}
 7310
 7311void *netdev_adjacent_get_private(struct list_head *adj_list)
 7312{
 7313	struct netdev_adjacent *adj;
 7314
 7315	adj = list_entry(adj_list, struct netdev_adjacent, list);
 7316
 7317	return adj->private;
 7318}
 7319EXPORT_SYMBOL(netdev_adjacent_get_private);
 7320
 7321/**
 7322 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list
 7323 * @dev: device
 7324 * @iter: list_head ** of the current position
 7325 *
 7326 * Gets the next device from the dev's upper list, starting from iter
 7327 * position. The caller must hold RCU read lock.
 7328 */
 7329struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
 7330						 struct list_head **iter)
 7331{
 7332	struct netdev_adjacent *upper;
 7333
 7334	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
 7335
 7336	upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
 7337
 7338	if (&upper->list == &dev->adj_list.upper)
 7339		return NULL;
 7340
 7341	*iter = &upper->list;
 7342
 7343	return upper->dev;
 7344}
 7345EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
 7346
 7347static struct net_device *__netdev_next_upper_dev(struct net_device *dev,
 7348						  struct list_head **iter,
 7349						  bool *ignore)
 7350{
 7351	struct netdev_adjacent *upper;
 7352
 7353	upper = list_entry((*iter)->next, struct netdev_adjacent, list);
 7354
 7355	if (&upper->list == &dev->adj_list.upper)
 7356		return NULL;
 7357
 7358	*iter = &upper->list;
 7359	*ignore = upper->ignore;
 7360
 7361	return upper->dev;
 7362}
 7363
 7364static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev,
 7365						    struct list_head **iter)
 7366{
 7367	struct netdev_adjacent *upper;
 7368
 7369	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
 7370
 7371	upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
 7372
 7373	if (&upper->list == &dev->adj_list.upper)
 7374		return NULL;
 7375
 7376	*iter = &upper->list;
 7377
 7378	return upper->dev;
 7379}
 7380
 7381static int __netdev_walk_all_upper_dev(struct net_device *dev,
 7382				       int (*fn)(struct net_device *dev,
 7383					 struct netdev_nested_priv *priv),
 7384				       struct netdev_nested_priv *priv)
 7385{
 7386	struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
 7387	struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
 7388	int ret, cur = 0;
 7389	bool ignore;
 7390
 7391	now = dev;
 7392	iter = &dev->adj_list.upper;
 7393
 7394	while (1) {
 7395		if (now != dev) {
 7396			ret = fn(now, priv);
 7397			if (ret)
 7398				return ret;
 7399		}
 7400
 7401		next = NULL;
 7402		while (1) {
 7403			udev = __netdev_next_upper_dev(now, &iter, &ignore);
 7404			if (!udev)
 7405				break;
 7406			if (ignore)
 7407				continue;
 7408
 7409			next = udev;
 7410			niter = &udev->adj_list.upper;
 7411			dev_stack[cur] = now;
 7412			iter_stack[cur++] = iter;
 7413			break;
 7414		}
 7415
 7416		if (!next) {
 7417			if (!cur)
 7418				return 0;
 7419			next = dev_stack[--cur];
 7420			niter = iter_stack[cur];
 7421		}
 7422
 7423		now = next;
 7424		iter = niter;
 
 
 
 7425	}
 7426
 7427	return 0;
 7428}
 7429
 7430int netdev_walk_all_upper_dev_rcu(struct net_device *dev,
 7431				  int (*fn)(struct net_device *dev,
 7432					    struct netdev_nested_priv *priv),
 7433				  struct netdev_nested_priv *priv)
 7434{
 7435	struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
 7436	struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
 7437	int ret, cur = 0;
 7438
 7439	now = dev;
 7440	iter = &dev->adj_list.upper;
 7441
 7442	while (1) {
 7443		if (now != dev) {
 7444			ret = fn(now, priv);
 7445			if (ret)
 7446				return ret;
 7447		}
 7448
 7449		next = NULL;
 7450		while (1) {
 7451			udev = netdev_next_upper_dev_rcu(now, &iter);
 7452			if (!udev)
 7453				break;
 7454
 7455			next = udev;
 7456			niter = &udev->adj_list.upper;
 7457			dev_stack[cur] = now;
 7458			iter_stack[cur++] = iter;
 7459			break;
 7460		}
 7461
 7462		if (!next) {
 7463			if (!cur)
 7464				return 0;
 7465			next = dev_stack[--cur];
 7466			niter = iter_stack[cur];
 7467		}
 7468
 7469		now = next;
 7470		iter = niter;
 7471	}
 7472
 
 
 7473	return 0;
 7474}
 7475EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu);
 7476
 7477static bool __netdev_has_upper_dev(struct net_device *dev,
 7478				   struct net_device *upper_dev)
 7479{
 7480	struct netdev_nested_priv priv = {
 7481		.flags = 0,
 7482		.data = (void *)upper_dev,
 7483	};
 7484
 7485	ASSERT_RTNL();
 7486
 7487	return __netdev_walk_all_upper_dev(dev, ____netdev_has_upper_dev,
 7488					   &priv);
 7489}
 7490
 7491/**
 7492 * netdev_lower_get_next_private - Get the next ->private from the
 7493 *				   lower neighbour list
 7494 * @dev: device
 7495 * @iter: list_head ** of the current position
 7496 *
 7497 * Gets the next netdev_adjacent->private from the dev's lower neighbour
 7498 * list, starting from iter position. The caller must hold either hold the
 7499 * RTNL lock or its own locking that guarantees that the neighbour lower
 7500 * list will remain unchanged.
 7501 */
 7502void *netdev_lower_get_next_private(struct net_device *dev,
 7503				    struct list_head **iter)
 7504{
 7505	struct netdev_adjacent *lower;
 7506
 7507	lower = list_entry(*iter, struct netdev_adjacent, list);
 7508
 7509	if (&lower->list == &dev->adj_list.lower)
 7510		return NULL;
 7511
 7512	*iter = lower->list.next;
 7513
 7514	return lower->private;
 7515}
 7516EXPORT_SYMBOL(netdev_lower_get_next_private);
 7517
 7518/**
 7519 * netdev_lower_get_next_private_rcu - Get the next ->private from the
 7520 *				       lower neighbour list, RCU
 7521 *				       variant
 7522 * @dev: device
 7523 * @iter: list_head ** of the current position
 7524 *
 7525 * Gets the next netdev_adjacent->private from the dev's lower neighbour
 7526 * list, starting from iter position. The caller must hold RCU read lock.
 7527 */
 7528void *netdev_lower_get_next_private_rcu(struct net_device *dev,
 7529					struct list_head **iter)
 7530{
 7531	struct netdev_adjacent *lower;
 7532
 7533	WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
 7534
 7535	lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
 7536
 7537	if (&lower->list == &dev->adj_list.lower)
 7538		return NULL;
 7539
 7540	*iter = &lower->list;
 7541
 7542	return lower->private;
 7543}
 7544EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
 7545
 7546/**
 7547 * netdev_lower_get_next - Get the next device from the lower neighbour
 7548 *                         list
 7549 * @dev: device
 7550 * @iter: list_head ** of the current position
 7551 *
 7552 * Gets the next netdev_adjacent from the dev's lower neighbour
 7553 * list, starting from iter position. The caller must hold RTNL lock or
 7554 * its own locking that guarantees that the neighbour lower
 7555 * list will remain unchanged.
 7556 */
 7557void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
 7558{
 7559	struct netdev_adjacent *lower;
 7560
 7561	lower = list_entry(*iter, struct netdev_adjacent, list);
 7562
 7563	if (&lower->list == &dev->adj_list.lower)
 7564		return NULL;
 7565
 7566	*iter = lower->list.next;
 7567
 7568	return lower->dev;
 7569}
 7570EXPORT_SYMBOL(netdev_lower_get_next);
 7571
 7572static struct net_device *netdev_next_lower_dev(struct net_device *dev,
 7573						struct list_head **iter)
 7574{
 7575	struct netdev_adjacent *lower;
 7576
 7577	lower = list_entry((*iter)->next, struct netdev_adjacent, list);
 7578
 7579	if (&lower->list == &dev->adj_list.lower)
 7580		return NULL;
 7581
 7582	*iter = &lower->list;
 7583
 7584	return lower->dev;
 7585}
 7586
 7587static struct net_device *__netdev_next_lower_dev(struct net_device *dev,
 7588						  struct list_head **iter,
 7589						  bool *ignore)
 7590{
 7591	struct netdev_adjacent *lower;
 7592
 7593	lower = list_entry((*iter)->next, struct netdev_adjacent, list);
 7594
 7595	if (&lower->list == &dev->adj_list.lower)
 7596		return NULL;
 7597
 7598	*iter = &lower->list;
 7599	*ignore = lower->ignore;
 7600
 7601	return lower->dev;
 7602}
 7603
 7604int netdev_walk_all_lower_dev(struct net_device *dev,
 7605			      int (*fn)(struct net_device *dev,
 7606					struct netdev_nested_priv *priv),
 7607			      struct netdev_nested_priv *priv)
 7608{
 7609	struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
 7610	struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
 7611	int ret, cur = 0;
 7612
 7613	now = dev;
 7614	iter = &dev->adj_list.lower;
 
 7615
 7616	while (1) {
 7617		if (now != dev) {
 7618			ret = fn(now, priv);
 7619			if (ret)
 7620				return ret;
 7621		}
 7622
 7623		next = NULL;
 7624		while (1) {
 7625			ldev = netdev_next_lower_dev(now, &iter);
 7626			if (!ldev)
 7627				break;
 7628
 7629			next = ldev;
 7630			niter = &ldev->adj_list.lower;
 7631			dev_stack[cur] = now;
 7632			iter_stack[cur++] = iter;
 7633			break;
 7634		}
 7635
 7636		if (!next) {
 7637			if (!cur)
 7638				return 0;
 7639			next = dev_stack[--cur];
 7640			niter = iter_stack[cur];
 
 
 
 
 
 
 
 
 
 7641		}
 7642
 7643		now = next;
 7644		iter = niter;
 7645	}
 7646
 7647	return 0;
 7648}
 7649EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev);
 7650
 7651static int __netdev_walk_all_lower_dev(struct net_device *dev,
 7652				       int (*fn)(struct net_device *dev,
 7653					 struct netdev_nested_priv *priv),
 7654				       struct netdev_nested_priv *priv)
 7655{
 7656	struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
 7657	struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
 7658	int ret, cur = 0;
 7659	bool ignore;
 7660
 7661	now = dev;
 7662	iter = &dev->adj_list.lower;
 7663
 7664	while (1) {
 7665		if (now != dev) {
 7666			ret = fn(now, priv);
 7667			if (ret)
 7668				return ret;
 7669		}
 7670
 7671		next = NULL;
 7672		while (1) {
 7673			ldev = __netdev_next_lower_dev(now, &iter, &ignore);
 7674			if (!ldev)
 7675				break;
 7676			if (ignore)
 7677				continue;
 7678
 7679			next = ldev;
 7680			niter = &ldev->adj_list.lower;
 7681			dev_stack[cur] = now;
 7682			iter_stack[cur++] = iter;
 7683			break;
 7684		}
 7685
 7686		if (!next) {
 7687			if (!cur)
 7688				return 0;
 7689			next = dev_stack[--cur];
 7690			niter = iter_stack[cur];
 7691		}
 7692
 7693		now = next;
 7694		iter = niter;
 7695	}
 7696
 7697	return 0;
 
 
 
 7698}
 7699
 7700struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev,
 7701					     struct list_head **iter)
 
 
 
 
 
 7702{
 7703	struct netdev_adjacent *lower;
 7704
 7705	lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
 7706	if (&lower->list == &dev->adj_list.lower)
 7707		return NULL;
 7708
 7709	*iter = &lower->list;
 7710
 7711	return lower->dev;
 7712}
 7713EXPORT_SYMBOL(netdev_next_lower_dev_rcu);
 7714
 7715static u8 __netdev_upper_depth(struct net_device *dev)
 7716{
 7717	struct net_device *udev;
 7718	struct list_head *iter;
 7719	u8 max_depth = 0;
 7720	bool ignore;
 7721
 7722	for (iter = &dev->adj_list.upper,
 7723	     udev = __netdev_next_upper_dev(dev, &iter, &ignore);
 7724	     udev;
 7725	     udev = __netdev_next_upper_dev(dev, &iter, &ignore)) {
 7726		if (ignore)
 7727			continue;
 7728		if (max_depth < udev->upper_level)
 7729			max_depth = udev->upper_level;
 7730	}
 7731
 7732	return max_depth;
 7733}
 7734
 7735static u8 __netdev_lower_depth(struct net_device *dev)
 7736{
 7737	struct net_device *ldev;
 7738	struct list_head *iter;
 7739	u8 max_depth = 0;
 7740	bool ignore;
 7741
 7742	for (iter = &dev->adj_list.lower,
 7743	     ldev = __netdev_next_lower_dev(dev, &iter, &ignore);
 7744	     ldev;
 7745	     ldev = __netdev_next_lower_dev(dev, &iter, &ignore)) {
 7746		if (ignore)
 7747			continue;
 7748		if (max_depth < ldev->lower_level)
 7749			max_depth = ldev->lower_level;
 7750	}
 7751
 7752	return max_depth;
 7753}
 7754
 7755static int __netdev_update_upper_level(struct net_device *dev,
 7756				       struct netdev_nested_priv *__unused)
 7757{
 7758	dev->upper_level = __netdev_upper_depth(dev) + 1;
 7759	return 0;
 7760}
 7761
 7762#ifdef CONFIG_LOCKDEP
 7763static LIST_HEAD(net_unlink_list);
 7764
 7765static void net_unlink_todo(struct net_device *dev)
 7766{
 7767	if (list_empty(&dev->unlink_list))
 7768		list_add_tail(&dev->unlink_list, &net_unlink_list);
 7769}
 7770#endif
 7771
 7772static int __netdev_update_lower_level(struct net_device *dev,
 7773				       struct netdev_nested_priv *priv)
 7774{
 7775	dev->lower_level = __netdev_lower_depth(dev) + 1;
 7776
 7777#ifdef CONFIG_LOCKDEP
 7778	if (!priv)
 7779		return 0;
 7780
 7781	if (priv->flags & NESTED_SYNC_IMM)
 7782		dev->nested_level = dev->lower_level - 1;
 7783	if (priv->flags & NESTED_SYNC_TODO)
 7784		net_unlink_todo(dev);
 7785#endif
 7786	return 0;
 7787}
 7788
 7789int netdev_walk_all_lower_dev_rcu(struct net_device *dev,
 7790				  int (*fn)(struct net_device *dev,
 7791					    struct netdev_nested_priv *priv),
 7792				  struct netdev_nested_priv *priv)
 7793{
 7794	struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
 7795	struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
 7796	int ret, cur = 0;
 7797
 7798	now = dev;
 7799	iter = &dev->adj_list.lower;
 7800
 7801	while (1) {
 7802		if (now != dev) {
 7803			ret = fn(now, priv);
 7804			if (ret)
 7805				return ret;
 7806		}
 7807
 7808		next = NULL;
 7809		while (1) {
 7810			ldev = netdev_next_lower_dev_rcu(now, &iter);
 7811			if (!ldev)
 7812				break;
 7813
 7814			next = ldev;
 7815			niter = &ldev->adj_list.lower;
 7816			dev_stack[cur] = now;
 7817			iter_stack[cur++] = iter;
 7818			break;
 7819		}
 7820
 7821		if (!next) {
 7822			if (!cur)
 7823				return 0;
 7824			next = dev_stack[--cur];
 7825			niter = iter_stack[cur];
 7826		}
 7827
 7828		now = next;
 7829		iter = niter;
 7830	}
 7831
 7832	return 0;
 7833}
 7834EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu);
 7835
 7836/**
 7837 * netdev_lower_get_first_private_rcu - Get the first ->private from the
 7838 *				       lower neighbour list, RCU
 7839 *				       variant
 7840 * @dev: device
 7841 *
 7842 * Gets the first netdev_adjacent->private from the dev's lower neighbour
 7843 * list. The caller must hold RCU read lock.
 7844 */
 7845void *netdev_lower_get_first_private_rcu(struct net_device *dev)
 7846{
 7847	struct netdev_adjacent *lower;
 7848
 7849	lower = list_first_or_null_rcu(&dev->adj_list.lower,
 7850			struct netdev_adjacent, list);
 7851	if (lower)
 7852		return lower->private;
 7853	return NULL;
 
 
 7854}
 7855EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
 7856
 7857/**
 7858 * netdev_master_upper_dev_get_rcu - Get master upper device
 7859 * @dev: device
 7860 *
 7861 * Find a master upper device and return pointer to it or NULL in case
 7862 * it's not there. The caller must hold the RCU read lock.
 7863 */
 7864struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
 7865{
 7866	struct netdev_adjacent *upper;
 7867
 7868	upper = list_first_or_null_rcu(&dev->adj_list.upper,
 7869				       struct netdev_adjacent, list);
 7870	if (upper && likely(upper->master))
 7871		return upper->dev;
 7872	return NULL;
 
 
 7873}
 7874EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
 7875
 7876static int netdev_adjacent_sysfs_add(struct net_device *dev,
 7877			      struct net_device *adj_dev,
 7878			      struct list_head *dev_list)
 7879{
 7880	char linkname[IFNAMSIZ+7];
 7881
 7882	sprintf(linkname, dev_list == &dev->adj_list.upper ?
 7883		"upper_%s" : "lower_%s", adj_dev->name);
 7884	return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
 7885				 linkname);
 7886}
 7887static void netdev_adjacent_sysfs_del(struct net_device *dev,
 7888			       char *name,
 7889			       struct list_head *dev_list)
 7890{
 7891	char linkname[IFNAMSIZ+7];
 7892
 7893	sprintf(linkname, dev_list == &dev->adj_list.upper ?
 7894		"upper_%s" : "lower_%s", name);
 7895	sysfs_remove_link(&(dev->dev.kobj), linkname);
 7896}
 7897
 7898static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev,
 7899						 struct net_device *adj_dev,
 7900						 struct list_head *dev_list)
 7901{
 7902	return (dev_list == &dev->adj_list.upper ||
 7903		dev_list == &dev->adj_list.lower) &&
 7904		net_eq(dev_net(dev), dev_net(adj_dev));
 7905}
 7906
 7907static int __netdev_adjacent_dev_insert(struct net_device *dev,
 7908					struct net_device *adj_dev,
 7909					struct list_head *dev_list,
 7910					void *private, bool master)
 7911{
 7912	struct netdev_adjacent *adj;
 7913	int ret;
 7914
 7915	adj = __netdev_find_adj(adj_dev, dev_list);
 7916
 7917	if (adj) {
 7918		adj->ref_nr += 1;
 7919		pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n",
 7920			 dev->name, adj_dev->name, adj->ref_nr);
 7921
 7922		return 0;
 7923	}
 7924
 7925	adj = kmalloc(sizeof(*adj), GFP_KERNEL);
 7926	if (!adj)
 7927		return -ENOMEM;
 7928
 7929	adj->dev = adj_dev;
 7930	adj->master = master;
 7931	adj->ref_nr = 1;
 7932	adj->private = private;
 7933	adj->ignore = false;
 7934	netdev_hold(adj_dev, &adj->dev_tracker, GFP_KERNEL);
 7935
 7936	pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n",
 7937		 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name);
 7938
 7939	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
 7940		ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
 7941		if (ret)
 7942			goto free_adj;
 7943	}
 7944
 7945	/* Ensure that master link is always the first item in list. */
 7946	if (master) {
 7947		ret = sysfs_create_link(&(dev->dev.kobj),
 7948					&(adj_dev->dev.kobj), "master");
 7949		if (ret)
 7950			goto remove_symlinks;
 7951
 7952		list_add_rcu(&adj->list, dev_list);
 7953	} else {
 7954		list_add_tail_rcu(&adj->list, dev_list);
 7955	}
 7956
 7957	return 0;
 7958
 7959remove_symlinks:
 7960	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
 7961		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
 7962free_adj:
 7963	netdev_put(adj_dev, &adj->dev_tracker);
 7964	kfree(adj);
 7965
 7966	return ret;
 7967}
 7968
 7969static void __netdev_adjacent_dev_remove(struct net_device *dev,
 7970					 struct net_device *adj_dev,
 7971					 u16 ref_nr,
 7972					 struct list_head *dev_list)
 7973{
 7974	struct netdev_adjacent *adj;
 7975
 7976	pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n",
 7977		 dev->name, adj_dev->name, ref_nr);
 7978
 7979	adj = __netdev_find_adj(adj_dev, dev_list);
 7980
 7981	if (!adj) {
 7982		pr_err("Adjacency does not exist for device %s from %s\n",
 7983		       dev->name, adj_dev->name);
 7984		WARN_ON(1);
 7985		return;
 7986	}
 7987
 7988	if (adj->ref_nr > ref_nr) {
 7989		pr_debug("adjacency: %s to %s ref_nr - %d = %d\n",
 7990			 dev->name, adj_dev->name, ref_nr,
 7991			 adj->ref_nr - ref_nr);
 7992		adj->ref_nr -= ref_nr;
 7993		return;
 7994	}
 7995
 7996	if (adj->master)
 7997		sysfs_remove_link(&(dev->dev.kobj), "master");
 7998
 7999	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
 8000		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
 8001
 8002	list_del_rcu(&adj->list);
 8003	pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n",
 8004		 adj_dev->name, dev->name, adj_dev->name);
 8005	netdev_put(adj_dev, &adj->dev_tracker);
 8006	kfree_rcu(adj, rcu);
 8007}
 8008
 8009static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
 8010					    struct net_device *upper_dev,
 8011					    struct list_head *up_list,
 8012					    struct list_head *down_list,
 8013					    void *private, bool master)
 8014{
 8015	int ret;
 8016
 8017	ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list,
 8018					   private, master);
 8019	if (ret)
 8020		return ret;
 8021
 8022	ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list,
 8023					   private, false);
 8024	if (ret) {
 8025		__netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list);
 8026		return ret;
 8027	}
 8028
 8029	return 0;
 8030}
 8031
 8032static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
 8033					       struct net_device *upper_dev,
 8034					       u16 ref_nr,
 8035					       struct list_head *up_list,
 8036					       struct list_head *down_list)
 8037{
 8038	__netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list);
 8039	__netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list);
 8040}
 8041
 8042static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
 8043						struct net_device *upper_dev,
 8044						void *private, bool master)
 8045{
 8046	return __netdev_adjacent_dev_link_lists(dev, upper_dev,
 8047						&dev->adj_list.upper,
 8048						&upper_dev->adj_list.lower,
 8049						private, master);
 8050}
 8051
 8052static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
 8053						   struct net_device *upper_dev)
 8054{
 8055	__netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1,
 8056					   &dev->adj_list.upper,
 8057					   &upper_dev->adj_list.lower);
 8058}
 8059
 8060static int __netdev_upper_dev_link(struct net_device *dev,
 8061				   struct net_device *upper_dev, bool master,
 8062				   void *upper_priv, void *upper_info,
 8063				   struct netdev_nested_priv *priv,
 8064				   struct netlink_ext_ack *extack)
 8065{
 8066	struct netdev_notifier_changeupper_info changeupper_info = {
 8067		.info = {
 8068			.dev = dev,
 8069			.extack = extack,
 8070		},
 8071		.upper_dev = upper_dev,
 8072		.master = master,
 8073		.linking = true,
 8074		.upper_info = upper_info,
 8075	};
 8076	struct net_device *master_dev;
 8077	int ret = 0;
 8078
 8079	ASSERT_RTNL();
 8080
 8081	if (dev == upper_dev)
 8082		return -EBUSY;
 8083
 8084	/* To prevent loops, check if dev is not upper device to upper_dev. */
 8085	if (__netdev_has_upper_dev(upper_dev, dev))
 8086		return -EBUSY;
 8087
 8088	if ((dev->lower_level + upper_dev->upper_level) > MAX_NEST_DEV)
 8089		return -EMLINK;
 8090
 8091	if (!master) {
 8092		if (__netdev_has_upper_dev(dev, upper_dev))
 8093			return -EEXIST;
 8094	} else {
 8095		master_dev = __netdev_master_upper_dev_get(dev);
 8096		if (master_dev)
 8097			return master_dev == upper_dev ? -EEXIST : -EBUSY;
 8098	}
 8099
 8100	ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER,
 8101					    &changeupper_info.info);
 8102	ret = notifier_to_errno(ret);
 8103	if (ret)
 8104		return ret;
 8105
 8106	ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv,
 8107						   master);
 8108	if (ret)
 8109		return ret;
 8110
 8111	ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER,
 8112					    &changeupper_info.info);
 8113	ret = notifier_to_errno(ret);
 8114	if (ret)
 8115		goto rollback;
 8116
 8117	__netdev_update_upper_level(dev, NULL);
 8118	__netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL);
 8119
 8120	__netdev_update_lower_level(upper_dev, priv);
 8121	__netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level,
 8122				    priv);
 8123
 
 
 
 
 8124	return 0;
 8125
 8126rollback:
 8127	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
 8128
 8129	return ret;
 8130}
 8131
 8132/**
 8133 * netdev_upper_dev_link - Add a link to the upper device
 8134 * @dev: device
 8135 * @upper_dev: new upper device
 8136 * @extack: netlink extended ack
 8137 *
 8138 * Adds a link to device which is upper to this one. The caller must hold
 8139 * the RTNL lock. On a failure a negative errno code is returned.
 8140 * On success the reference counts are adjusted and the function
 8141 * returns zero.
 8142 */
 8143int netdev_upper_dev_link(struct net_device *dev,
 8144			  struct net_device *upper_dev,
 8145			  struct netlink_ext_ack *extack)
 8146{
 8147	struct netdev_nested_priv priv = {
 8148		.flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO,
 8149		.data = NULL,
 8150	};
 8151
 8152	return __netdev_upper_dev_link(dev, upper_dev, false,
 8153				       NULL, NULL, &priv, extack);
 8154}
 8155EXPORT_SYMBOL(netdev_upper_dev_link);
 8156
 8157/**
 8158 * netdev_master_upper_dev_link - Add a master link to the upper device
 8159 * @dev: device
 8160 * @upper_dev: new upper device
 8161 * @upper_priv: upper device private
 8162 * @upper_info: upper info to be passed down via notifier
 8163 * @extack: netlink extended ack
 8164 *
 8165 * Adds a link to device which is upper to this one. In this case, only
 8166 * one master upper device can be linked, although other non-master devices
 8167 * might be linked as well. The caller must hold the RTNL lock.
 8168 * On a failure a negative errno code is returned. On success the reference
 8169 * counts are adjusted and the function returns zero.
 8170 */
 8171int netdev_master_upper_dev_link(struct net_device *dev,
 8172				 struct net_device *upper_dev,
 8173				 void *upper_priv, void *upper_info,
 8174				 struct netlink_ext_ack *extack)
 8175{
 8176	struct netdev_nested_priv priv = {
 8177		.flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO,
 8178		.data = NULL,
 8179	};
 8180
 8181	return __netdev_upper_dev_link(dev, upper_dev, true,
 8182				       upper_priv, upper_info, &priv, extack);
 8183}
 8184EXPORT_SYMBOL(netdev_master_upper_dev_link);
 8185
 8186static void __netdev_upper_dev_unlink(struct net_device *dev,
 8187				      struct net_device *upper_dev,
 8188				      struct netdev_nested_priv *priv)
 8189{
 8190	struct netdev_notifier_changeupper_info changeupper_info = {
 8191		.info = {
 8192			.dev = dev,
 8193		},
 8194		.upper_dev = upper_dev,
 8195		.linking = false,
 8196	};
 8197
 8198	ASSERT_RTNL();
 8199
 8200	changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev;
 8201
 8202	call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER,
 8203				      &changeupper_info.info);
 8204
 8205	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
 8206
 8207	call_netdevice_notifiers_info(NETDEV_CHANGEUPPER,
 8208				      &changeupper_info.info);
 8209
 8210	__netdev_update_upper_level(dev, NULL);
 8211	__netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL);
 8212
 8213	__netdev_update_lower_level(upper_dev, priv);
 8214	__netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level,
 8215				    priv);
 8216}
 8217
 8218/**
 8219 * netdev_upper_dev_unlink - Removes a link to upper device
 8220 * @dev: device
 8221 * @upper_dev: new upper device
 8222 *
 8223 * Removes a link to device which is upper to this one. The caller must hold
 8224 * the RTNL lock.
 8225 */
 8226void netdev_upper_dev_unlink(struct net_device *dev,
 8227			     struct net_device *upper_dev)
 8228{
 8229	struct netdev_nested_priv priv = {
 8230		.flags = NESTED_SYNC_TODO,
 8231		.data = NULL,
 8232	};
 8233
 8234	__netdev_upper_dev_unlink(dev, upper_dev, &priv);
 8235}
 8236EXPORT_SYMBOL(netdev_upper_dev_unlink);
 8237
 8238static void __netdev_adjacent_dev_set(struct net_device *upper_dev,
 8239				      struct net_device *lower_dev,
 8240				      bool val)
 8241{
 8242	struct netdev_adjacent *adj;
 8243
 8244	adj = __netdev_find_adj(lower_dev, &upper_dev->adj_list.lower);
 8245	if (adj)
 8246		adj->ignore = val;
 8247
 8248	adj = __netdev_find_adj(upper_dev, &lower_dev->adj_list.upper);
 8249	if (adj)
 8250		adj->ignore = val;
 8251}
 
 
 8252
 8253static void netdev_adjacent_dev_disable(struct net_device *upper_dev,
 8254					struct net_device *lower_dev)
 8255{
 8256	__netdev_adjacent_dev_set(upper_dev, lower_dev, true);
 8257}
 8258
 8259static void netdev_adjacent_dev_enable(struct net_device *upper_dev,
 8260				       struct net_device *lower_dev)
 8261{
 8262	__netdev_adjacent_dev_set(upper_dev, lower_dev, false);
 8263}
 
 
 8264
 8265int netdev_adjacent_change_prepare(struct net_device *old_dev,
 8266				   struct net_device *new_dev,
 8267				   struct net_device *dev,
 8268				   struct netlink_ext_ack *extack)
 8269{
 8270	struct netdev_nested_priv priv = {
 8271		.flags = 0,
 8272		.data = NULL,
 8273	};
 8274	int err;
 8275
 8276	if (!new_dev)
 8277		return 0;
 8278
 8279	if (old_dev && new_dev != old_dev)
 8280		netdev_adjacent_dev_disable(dev, old_dev);
 8281	err = __netdev_upper_dev_link(new_dev, dev, false, NULL, NULL, &priv,
 8282				      extack);
 8283	if (err) {
 8284		if (old_dev && new_dev != old_dev)
 8285			netdev_adjacent_dev_enable(dev, old_dev);
 8286		return err;
 8287	}
 8288
 8289	return 0;
 8290}
 8291EXPORT_SYMBOL(netdev_adjacent_change_prepare);
 8292
 8293void netdev_adjacent_change_commit(struct net_device *old_dev,
 8294				   struct net_device *new_dev,
 8295				   struct net_device *dev)
 8296{
 8297	struct netdev_nested_priv priv = {
 8298		.flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO,
 8299		.data = NULL,
 8300	};
 8301
 8302	if (!new_dev || !old_dev)
 8303		return;
 8304
 8305	if (new_dev == old_dev)
 8306		return;
 8307
 8308	netdev_adjacent_dev_enable(dev, old_dev);
 8309	__netdev_upper_dev_unlink(old_dev, dev, &priv);
 8310}
 8311EXPORT_SYMBOL(netdev_adjacent_change_commit);
 8312
 8313void netdev_adjacent_change_abort(struct net_device *old_dev,
 8314				  struct net_device *new_dev,
 8315				  struct net_device *dev)
 8316{
 8317	struct netdev_nested_priv priv = {
 8318		.flags = 0,
 8319		.data = NULL,
 8320	};
 8321
 8322	if (!new_dev)
 8323		return;
 8324
 8325	if (old_dev && new_dev != old_dev)
 8326		netdev_adjacent_dev_enable(dev, old_dev);
 8327
 8328	__netdev_upper_dev_unlink(new_dev, dev, &priv);
 8329}
 8330EXPORT_SYMBOL(netdev_adjacent_change_abort);
 8331
 8332/**
 8333 * netdev_bonding_info_change - Dispatch event about slave change
 8334 * @dev: device
 8335 * @bonding_info: info to dispatch
 8336 *
 8337 * Send NETDEV_BONDING_INFO to netdev notifiers with info.
 8338 * The caller must hold the RTNL lock.
 8339 */
 8340void netdev_bonding_info_change(struct net_device *dev,
 8341				struct netdev_bonding_info *bonding_info)
 8342{
 8343	struct netdev_notifier_bonding_info info = {
 8344		.info.dev = dev,
 8345	};
 8346
 8347	memcpy(&info.bonding_info, bonding_info,
 8348	       sizeof(struct netdev_bonding_info));
 8349	call_netdevice_notifiers_info(NETDEV_BONDING_INFO,
 8350				      &info.info);
 8351}
 8352EXPORT_SYMBOL(netdev_bonding_info_change);
 8353
 8354static int netdev_offload_xstats_enable_l3(struct net_device *dev,
 8355					   struct netlink_ext_ack *extack)
 8356{
 8357	struct netdev_notifier_offload_xstats_info info = {
 8358		.info.dev = dev,
 8359		.info.extack = extack,
 8360		.type = NETDEV_OFFLOAD_XSTATS_TYPE_L3,
 8361	};
 8362	int err;
 8363	int rc;
 8364
 8365	dev->offload_xstats_l3 = kzalloc(sizeof(*dev->offload_xstats_l3),
 8366					 GFP_KERNEL);
 8367	if (!dev->offload_xstats_l3)
 8368		return -ENOMEM;
 8369
 8370	rc = call_netdevice_notifiers_info_robust(NETDEV_OFFLOAD_XSTATS_ENABLE,
 8371						  NETDEV_OFFLOAD_XSTATS_DISABLE,
 8372						  &info.info);
 8373	err = notifier_to_errno(rc);
 8374	if (err)
 8375		goto free_stats;
 8376
 8377	return 0;
 8378
 8379free_stats:
 8380	kfree(dev->offload_xstats_l3);
 8381	dev->offload_xstats_l3 = NULL;
 8382	return err;
 8383}
 8384
 8385int netdev_offload_xstats_enable(struct net_device *dev,
 8386				 enum netdev_offload_xstats_type type,
 8387				 struct netlink_ext_ack *extack)
 8388{
 8389	ASSERT_RTNL();
 8390
 8391	if (netdev_offload_xstats_enabled(dev, type))
 8392		return -EALREADY;
 
 
 
 
 
 
 
 
 
 
 
 
 
 8393
 8394	switch (type) {
 8395	case NETDEV_OFFLOAD_XSTATS_TYPE_L3:
 8396		return netdev_offload_xstats_enable_l3(dev, extack);
 
 8397	}
 8398
 8399	WARN_ON(1);
 8400	return -EINVAL;
 8401}
 8402EXPORT_SYMBOL(netdev_offload_xstats_enable);
 8403
 8404static void netdev_offload_xstats_disable_l3(struct net_device *dev)
 
 8405{
 8406	struct netdev_notifier_offload_xstats_info info = {
 8407		.info.dev = dev,
 8408		.type = NETDEV_OFFLOAD_XSTATS_TYPE_L3,
 8409	};
 8410
 8411	call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_DISABLE,
 8412				      &info.info);
 8413	kfree(dev->offload_xstats_l3);
 8414	dev->offload_xstats_l3 = NULL;
 8415}
 8416
 8417int netdev_offload_xstats_disable(struct net_device *dev,
 8418				  enum netdev_offload_xstats_type type)
 8419{
 8420	ASSERT_RTNL();
 8421
 8422	if (!netdev_offload_xstats_enabled(dev, type))
 8423		return -EALREADY;
 
 
 
 
 
 8424
 8425	switch (type) {
 8426	case NETDEV_OFFLOAD_XSTATS_TYPE_L3:
 8427		netdev_offload_xstats_disable_l3(dev);
 8428		return 0;
 8429	}
 8430
 8431	WARN_ON(1);
 8432	return -EINVAL;
 8433}
 8434EXPORT_SYMBOL(netdev_offload_xstats_disable);
 8435
 8436static void netdev_offload_xstats_disable_all(struct net_device *dev)
 8437{
 8438	netdev_offload_xstats_disable(dev, NETDEV_OFFLOAD_XSTATS_TYPE_L3);
 8439}
 8440
 8441static struct rtnl_hw_stats64 *
 8442netdev_offload_xstats_get_ptr(const struct net_device *dev,
 8443			      enum netdev_offload_xstats_type type)
 8444{
 8445	switch (type) {
 8446	case NETDEV_OFFLOAD_XSTATS_TYPE_L3:
 8447		return dev->offload_xstats_l3;
 8448	}
 8449
 8450	WARN_ON(1);
 8451	return NULL;
 8452}
 8453
 8454bool netdev_offload_xstats_enabled(const struct net_device *dev,
 8455				   enum netdev_offload_xstats_type type)
 8456{
 8457	ASSERT_RTNL();
 8458
 8459	return netdev_offload_xstats_get_ptr(dev, type);
 8460}
 8461EXPORT_SYMBOL(netdev_offload_xstats_enabled);
 8462
 8463struct netdev_notifier_offload_xstats_ru {
 8464	bool used;
 8465};
 8466
 8467struct netdev_notifier_offload_xstats_rd {
 8468	struct rtnl_hw_stats64 stats;
 8469	bool used;
 
 
 
 8470};
 8471
 8472static void netdev_hw_stats64_add(struct rtnl_hw_stats64 *dest,
 8473				  const struct rtnl_hw_stats64 *src)
 8474{
 8475	dest->rx_packets	  += src->rx_packets;
 8476	dest->tx_packets	  += src->tx_packets;
 8477	dest->rx_bytes		  += src->rx_bytes;
 8478	dest->tx_bytes		  += src->tx_bytes;
 8479	dest->rx_errors		  += src->rx_errors;
 8480	dest->tx_errors		  += src->tx_errors;
 8481	dest->rx_dropped	  += src->rx_dropped;
 8482	dest->tx_dropped	  += src->tx_dropped;
 8483	dest->multicast		  += src->multicast;
 8484}
 8485
 8486static int netdev_offload_xstats_get_used(struct net_device *dev,
 8487					  enum netdev_offload_xstats_type type,
 8488					  bool *p_used,
 8489					  struct netlink_ext_ack *extack)
 8490{
 8491	struct netdev_notifier_offload_xstats_ru report_used = {};
 8492	struct netdev_notifier_offload_xstats_info info = {
 8493		.info.dev = dev,
 8494		.info.extack = extack,
 8495		.type = type,
 8496		.report_used = &report_used,
 8497	};
 8498	int rc;
 8499
 8500	WARN_ON(!netdev_offload_xstats_enabled(dev, type));
 8501	rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_USED,
 8502					   &info.info);
 8503	*p_used = report_used.used;
 8504	return notifier_to_errno(rc);
 8505}
 8506
 8507static int netdev_offload_xstats_get_stats(struct net_device *dev,
 8508					   enum netdev_offload_xstats_type type,
 8509					   struct rtnl_hw_stats64 *p_stats,
 8510					   bool *p_used,
 8511					   struct netlink_ext_ack *extack)
 8512{
 8513	struct netdev_notifier_offload_xstats_rd report_delta = {};
 8514	struct netdev_notifier_offload_xstats_info info = {
 8515		.info.dev = dev,
 8516		.info.extack = extack,
 8517		.type = type,
 8518		.report_delta = &report_delta,
 8519	};
 8520	struct rtnl_hw_stats64 *stats;
 8521	int rc;
 8522
 8523	stats = netdev_offload_xstats_get_ptr(dev, type);
 8524	if (WARN_ON(!stats))
 8525		return -EINVAL;
 8526
 8527	rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_DELTA,
 8528					   &info.info);
 8529
 8530	/* Cache whatever we got, even if there was an error, otherwise the
 8531	 * successful stats retrievals would get lost.
 8532	 */
 8533	netdev_hw_stats64_add(stats, &report_delta.stats);
 8534
 8535	if (p_stats)
 8536		*p_stats = *stats;
 8537	*p_used = report_delta.used;
 8538
 8539	return notifier_to_errno(rc);
 8540}
 8541
 8542int netdev_offload_xstats_get(struct net_device *dev,
 8543			      enum netdev_offload_xstats_type type,
 8544			      struct rtnl_hw_stats64 *p_stats, bool *p_used,
 8545			      struct netlink_ext_ack *extack)
 8546{
 8547	ASSERT_RTNL();
 8548
 8549	if (p_stats)
 8550		return netdev_offload_xstats_get_stats(dev, type, p_stats,
 8551						       p_used, extack);
 8552	else
 8553		return netdev_offload_xstats_get_used(dev, type, p_used,
 8554						      extack);
 8555}
 8556EXPORT_SYMBOL(netdev_offload_xstats_get);
 8557
 8558void
 8559netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *report_delta,
 8560				   const struct rtnl_hw_stats64 *stats)
 8561{
 8562	report_delta->used = true;
 8563	netdev_hw_stats64_add(&report_delta->stats, stats);
 8564}
 8565EXPORT_SYMBOL(netdev_offload_xstats_report_delta);
 8566
 8567void
 8568netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *report_used)
 8569{
 8570	report_used->used = true;
 
 
 
 
 
 
 
 
 8571}
 8572EXPORT_SYMBOL(netdev_offload_xstats_report_used);
 8573
 8574void netdev_offload_xstats_push_delta(struct net_device *dev,
 8575				      enum netdev_offload_xstats_type type,
 8576				      const struct rtnl_hw_stats64 *p_stats)
 8577{
 8578	struct rtnl_hw_stats64 *stats;
 8579
 8580	ASSERT_RTNL();
 8581
 8582	stats = netdev_offload_xstats_get_ptr(dev, type);
 8583	if (WARN_ON(!stats))
 8584		return;
 8585
 8586	netdev_hw_stats64_add(stats, p_stats);
 
 
 8587}
 8588EXPORT_SYMBOL(netdev_offload_xstats_push_delta);
 8589
 8590/**
 8591 * netdev_get_xmit_slave - Get the xmit slave of master device
 8592 * @dev: device
 8593 * @skb: The packet
 8594 * @all_slaves: assume all the slaves are active
 8595 *
 8596 * The reference counters are not incremented so the caller must be
 8597 * careful with locks. The caller must hold RCU lock.
 8598 * %NULL is returned if no slave is found.
 8599 */
 8600
 8601struct net_device *netdev_get_xmit_slave(struct net_device *dev,
 8602					 struct sk_buff *skb,
 8603					 bool all_slaves)
 8604{
 8605	const struct net_device_ops *ops = dev->netdev_ops;
 8606
 8607	if (!ops->ndo_get_xmit_slave)
 8608		return NULL;
 8609	return ops->ndo_get_xmit_slave(dev, skb, all_slaves);
 8610}
 8611EXPORT_SYMBOL(netdev_get_xmit_slave);
 8612
 8613static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev,
 8614						  struct sock *sk)
 8615{
 8616	const struct net_device_ops *ops = dev->netdev_ops;
 8617
 8618	if (!ops->ndo_sk_get_lower_dev)
 8619		return NULL;
 8620	return ops->ndo_sk_get_lower_dev(dev, sk);
 8621}
 8622
 8623/**
 8624 * netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket
 8625 * @dev: device
 8626 * @sk: the socket
 8627 *
 8628 * %NULL is returned if no lower device is found.
 
 
 
 8629 */
 8630
 8631struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev,
 8632					    struct sock *sk)
 8633{
 8634	struct net_device *lower;
 8635
 8636	lower = netdev_sk_get_lower_dev(dev, sk);
 8637	while (lower) {
 8638		dev = lower;
 8639		lower = netdev_sk_get_lower_dev(dev, sk);
 8640	}
 8641
 8642	return dev;
 8643}
 8644EXPORT_SYMBOL(netdev_sk_get_lowest_dev);
 8645
 8646static void netdev_adjacent_add_links(struct net_device *dev)
 8647{
 8648	struct netdev_adjacent *iter;
 8649
 8650	struct net *net = dev_net(dev);
 8651
 8652	list_for_each_entry(iter, &dev->adj_list.upper, list) {
 8653		if (!net_eq(net, dev_net(iter->dev)))
 8654			continue;
 8655		netdev_adjacent_sysfs_add(iter->dev, dev,
 8656					  &iter->dev->adj_list.lower);
 8657		netdev_adjacent_sysfs_add(dev, iter->dev,
 8658					  &dev->adj_list.upper);
 8659	}
 8660
 8661	list_for_each_entry(iter, &dev->adj_list.lower, list) {
 8662		if (!net_eq(net, dev_net(iter->dev)))
 8663			continue;
 8664		netdev_adjacent_sysfs_add(iter->dev, dev,
 8665					  &iter->dev->adj_list.upper);
 8666		netdev_adjacent_sysfs_add(dev, iter->dev,
 8667					  &dev->adj_list.lower);
 8668	}
 8669}
 8670
 8671static void netdev_adjacent_del_links(struct net_device *dev)
 8672{
 8673	struct netdev_adjacent *iter;
 8674
 8675	struct net *net = dev_net(dev);
 8676
 8677	list_for_each_entry(iter, &dev->adj_list.upper, list) {
 8678		if (!net_eq(net, dev_net(iter->dev)))
 8679			continue;
 8680		netdev_adjacent_sysfs_del(iter->dev, dev->name,
 8681					  &iter->dev->adj_list.lower);
 8682		netdev_adjacent_sysfs_del(dev, iter->dev->name,
 8683					  &dev->adj_list.upper);
 8684	}
 8685
 8686	list_for_each_entry(iter, &dev->adj_list.lower, list) {
 8687		if (!net_eq(net, dev_net(iter->dev)))
 8688			continue;
 8689		netdev_adjacent_sysfs_del(iter->dev, dev->name,
 8690					  &iter->dev->adj_list.upper);
 8691		netdev_adjacent_sysfs_del(dev, iter->dev->name,
 8692					  &dev->adj_list.lower);
 8693	}
 8694}
 8695
 8696void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
 8697{
 8698	struct netdev_adjacent *iter;
 8699
 8700	struct net *net = dev_net(dev);
 8701
 8702	list_for_each_entry(iter, &dev->adj_list.upper, list) {
 8703		if (!net_eq(net, dev_net(iter->dev)))
 8704			continue;
 8705		netdev_adjacent_sysfs_del(iter->dev, oldname,
 8706					  &iter->dev->adj_list.lower);
 8707		netdev_adjacent_sysfs_add(iter->dev, dev,
 8708					  &iter->dev->adj_list.lower);
 8709	}
 8710
 8711	list_for_each_entry(iter, &dev->adj_list.lower, list) {
 8712		if (!net_eq(net, dev_net(iter->dev)))
 8713			continue;
 8714		netdev_adjacent_sysfs_del(iter->dev, oldname,
 8715					  &iter->dev->adj_list.upper);
 8716		netdev_adjacent_sysfs_add(iter->dev, dev,
 8717					  &iter->dev->adj_list.upper);
 8718	}
 8719}
 8720
 8721void *netdev_lower_dev_get_private(struct net_device *dev,
 8722				   struct net_device *lower_dev)
 8723{
 8724	struct netdev_adjacent *lower;
 8725
 8726	if (!lower_dev)
 8727		return NULL;
 8728	lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower);
 8729	if (!lower)
 8730		return NULL;
 8731
 8732	return lower->private;
 8733}
 8734EXPORT_SYMBOL(netdev_lower_dev_get_private);
 8735
 8736
 8737/**
 8738 * netdev_lower_state_changed - Dispatch event about lower device state change
 8739 * @lower_dev: device
 8740 * @lower_state_info: state to dispatch
 8741 *
 8742 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info.
 8743 * The caller must hold the RTNL lock.
 
 
 8744 */
 8745void netdev_lower_state_changed(struct net_device *lower_dev,
 8746				void *lower_state_info)
 8747{
 8748	struct netdev_notifier_changelowerstate_info changelowerstate_info = {
 8749		.info.dev = lower_dev,
 8750	};
 8751
 8752	ASSERT_RTNL();
 8753	changelowerstate_info.lower_state_info = lower_state_info;
 8754	call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE,
 8755				      &changelowerstate_info.info);
 
 
 
 
 
 
 
 
 8756}
 8757EXPORT_SYMBOL(netdev_lower_state_changed);
 8758
 8759static void dev_change_rx_flags(struct net_device *dev, int flags)
 8760{
 8761	const struct net_device_ops *ops = dev->netdev_ops;
 8762
 8763	if (ops->ndo_change_rx_flags)
 8764		ops->ndo_change_rx_flags(dev, flags);
 8765}
 8766
 8767static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
 8768{
 8769	unsigned int old_flags = dev->flags;
 8770	unsigned int promiscuity, flags;
 8771	kuid_t uid;
 8772	kgid_t gid;
 8773
 8774	ASSERT_RTNL();
 8775
 8776	promiscuity = dev->promiscuity + inc;
 8777	if (promiscuity == 0) {
 
 8778		/*
 8779		 * Avoid overflow.
 8780		 * If inc causes overflow, untouch promisc and return error.
 8781		 */
 8782		if (unlikely(inc > 0)) {
 8783			netdev_warn(dev, "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n");
 
 
 
 
 
 8784			return -EOVERFLOW;
 8785		}
 8786		flags = old_flags & ~IFF_PROMISC;
 8787	} else {
 8788		flags = old_flags | IFF_PROMISC;
 8789	}
 8790	WRITE_ONCE(dev->promiscuity, promiscuity);
 8791	if (flags != old_flags) {
 8792		WRITE_ONCE(dev->flags, flags);
 8793		netdev_info(dev, "%s promiscuous mode\n",
 8794			    dev->flags & IFF_PROMISC ? "entered" : "left");
 8795		if (audit_enabled) {
 8796			current_uid_gid(&uid, &gid);
 8797			audit_log(audit_context(), GFP_ATOMIC,
 8798				  AUDIT_ANOM_PROMISCUOUS,
 8799				  "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
 8800				  dev->name, (dev->flags & IFF_PROMISC),
 8801				  (old_flags & IFF_PROMISC),
 8802				  from_kuid(&init_user_ns, audit_get_loginuid(current)),
 8803				  from_kuid(&init_user_ns, uid),
 8804				  from_kgid(&init_user_ns, gid),
 8805				  audit_get_sessionid(current));
 8806		}
 8807
 8808		dev_change_rx_flags(dev, IFF_PROMISC);
 8809	}
 8810	if (notify)
 8811		__dev_notify_flags(dev, old_flags, IFF_PROMISC, 0, NULL);
 8812	return 0;
 8813}
 8814
 8815/**
 8816 *	dev_set_promiscuity	- update promiscuity count on a device
 8817 *	@dev: device
 8818 *	@inc: modifier
 8819 *
 8820 *	Add or remove promiscuity from a device. While the count in the device
 8821 *	remains above zero the interface remains promiscuous. Once it hits zero
 8822 *	the device reverts back to normal filtering operation. A negative inc
 8823 *	value is used to drop promiscuity on the device.
 8824 *	Return 0 if successful or a negative errno code on error.
 8825 */
 8826int dev_set_promiscuity(struct net_device *dev, int inc)
 8827{
 8828	unsigned int old_flags = dev->flags;
 8829	int err;
 8830
 8831	err = __dev_set_promiscuity(dev, inc, true);
 8832	if (err < 0)
 8833		return err;
 8834	if (dev->flags != old_flags)
 8835		dev_set_rx_mode(dev);
 8836	return err;
 8837}
 8838EXPORT_SYMBOL(dev_set_promiscuity);
 8839
 8840static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
 8841{
 8842	unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
 8843	unsigned int allmulti, flags;
 8844
 8845	ASSERT_RTNL();
 8846
 8847	allmulti = dev->allmulti + inc;
 8848	if (allmulti == 0) {
 8849		/*
 8850		 * Avoid overflow.
 8851		 * If inc causes overflow, untouch allmulti and return error.
 8852		 */
 8853		if (unlikely(inc > 0)) {
 8854			netdev_warn(dev, "allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n");
 8855			return -EOVERFLOW;
 8856		}
 8857		flags = old_flags & ~IFF_ALLMULTI;
 8858	} else {
 8859		flags = old_flags | IFF_ALLMULTI;
 8860	}
 8861	WRITE_ONCE(dev->allmulti, allmulti);
 8862	if (flags != old_flags) {
 8863		WRITE_ONCE(dev->flags, flags);
 8864		netdev_info(dev, "%s allmulticast mode\n",
 8865			    dev->flags & IFF_ALLMULTI ? "entered" : "left");
 8866		dev_change_rx_flags(dev, IFF_ALLMULTI);
 8867		dev_set_rx_mode(dev);
 8868		if (notify)
 8869			__dev_notify_flags(dev, old_flags,
 8870					   dev->gflags ^ old_gflags, 0, NULL);
 8871	}
 8872	return 0;
 8873}
 8874
 8875/**
 8876 *	dev_set_allmulti	- update allmulti count on a device
 8877 *	@dev: device
 8878 *	@inc: modifier
 8879 *
 8880 *	Add or remove reception of all multicast frames to a device. While the
 8881 *	count in the device remains above zero the interface remains listening
 8882 *	to all interfaces. Once it hits zero the device reverts back to normal
 8883 *	filtering operation. A negative @inc value is used to drop the counter
 8884 *	when releasing a resource needing all multicasts.
 8885 *	Return 0 if successful or a negative errno code on error.
 8886 */
 8887
 8888int dev_set_allmulti(struct net_device *dev, int inc)
 8889{
 8890	return __dev_set_allmulti(dev, inc, true);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 8891}
 8892EXPORT_SYMBOL(dev_set_allmulti);
 8893
 8894/*
 8895 *	Upload unicast and multicast address lists to device and
 8896 *	configure RX filtering. When the device doesn't support unicast
 8897 *	filtering it is put in promiscuous mode while unicast addresses
 8898 *	are present.
 8899 */
 8900void __dev_set_rx_mode(struct net_device *dev)
 8901{
 8902	const struct net_device_ops *ops = dev->netdev_ops;
 8903
 8904	/* dev_open will call this function so the list will stay sane. */
 8905	if (!(dev->flags&IFF_UP))
 8906		return;
 8907
 8908	if (!netif_device_present(dev))
 8909		return;
 8910
 8911	if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
 
 
 8912		/* Unicast addresses changes may only happen under the rtnl,
 8913		 * therefore calling __dev_set_promiscuity here is safe.
 8914		 */
 8915		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
 8916			__dev_set_promiscuity(dev, 1, false);
 8917			dev->uc_promisc = true;
 8918		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {
 8919			__dev_set_promiscuity(dev, -1, false);
 8920			dev->uc_promisc = false;
 8921		}
 8922	}
 8923
 8924	if (ops->ndo_set_rx_mode)
 8925		ops->ndo_set_rx_mode(dev);
 
 8926}
 8927
 8928void dev_set_rx_mode(struct net_device *dev)
 8929{
 8930	netif_addr_lock_bh(dev);
 8931	__dev_set_rx_mode(dev);
 8932	netif_addr_unlock_bh(dev);
 8933}
 8934
 8935/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 8936 *	dev_get_flags - get flags reported to userspace
 8937 *	@dev: device
 8938 *
 8939 *	Get the combination of flag bits exported through APIs to userspace.
 8940 */
 8941unsigned int dev_get_flags(const struct net_device *dev)
 8942{
 8943	unsigned int flags;
 8944
 8945	flags = (READ_ONCE(dev->flags) & ~(IFF_PROMISC |
 8946				IFF_ALLMULTI |
 8947				IFF_RUNNING |
 8948				IFF_LOWER_UP |
 8949				IFF_DORMANT)) |
 8950		(READ_ONCE(dev->gflags) & (IFF_PROMISC |
 8951				IFF_ALLMULTI));
 8952
 8953	if (netif_running(dev)) {
 8954		if (netif_oper_up(dev))
 8955			flags |= IFF_RUNNING;
 8956		if (netif_carrier_ok(dev))
 8957			flags |= IFF_LOWER_UP;
 8958		if (netif_dormant(dev))
 8959			flags |= IFF_DORMANT;
 8960	}
 8961
 8962	return flags;
 8963}
 8964EXPORT_SYMBOL(dev_get_flags);
 8965
 8966int __dev_change_flags(struct net_device *dev, unsigned int flags,
 8967		       struct netlink_ext_ack *extack)
 8968{
 8969	unsigned int old_flags = dev->flags;
 8970	int ret;
 8971
 8972	ASSERT_RTNL();
 8973
 8974	/*
 8975	 *	Set the flags on our device.
 8976	 */
 8977
 8978	dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
 8979			       IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
 8980			       IFF_AUTOMEDIA)) |
 8981		     (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
 8982				    IFF_ALLMULTI));
 8983
 8984	/*
 8985	 *	Load in the correct multicast list now the flags have changed.
 8986	 */
 8987
 8988	if ((old_flags ^ flags) & IFF_MULTICAST)
 8989		dev_change_rx_flags(dev, IFF_MULTICAST);
 8990
 8991	dev_set_rx_mode(dev);
 8992
 8993	/*
 8994	 *	Have we downed the interface. We handle IFF_UP ourselves
 8995	 *	according to user attempts to set it, rather than blindly
 8996	 *	setting it.
 8997	 */
 8998
 8999	ret = 0;
 9000	if ((old_flags ^ flags) & IFF_UP) {
 9001		if (old_flags & IFF_UP)
 9002			__dev_close(dev);
 9003		else
 9004			ret = __dev_open(dev, extack);
 9005	}
 9006
 9007	if ((flags ^ dev->gflags) & IFF_PROMISC) {
 9008		int inc = (flags & IFF_PROMISC) ? 1 : -1;
 9009		unsigned int old_flags = dev->flags;
 9010
 9011		dev->gflags ^= IFF_PROMISC;
 9012
 9013		if (__dev_set_promiscuity(dev, inc, false) >= 0)
 9014			if (dev->flags != old_flags)
 9015				dev_set_rx_mode(dev);
 9016	}
 9017
 9018	/* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
 9019	 * is important. Some (broken) drivers set IFF_PROMISC, when
 9020	 * IFF_ALLMULTI is requested not asking us and not reporting.
 9021	 */
 9022	if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
 9023		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
 9024
 9025		dev->gflags ^= IFF_ALLMULTI;
 9026		__dev_set_allmulti(dev, inc, false);
 9027	}
 9028
 9029	return ret;
 9030}
 9031
 9032void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
 9033			unsigned int gchanges, u32 portid,
 9034			const struct nlmsghdr *nlh)
 9035{
 9036	unsigned int changes = dev->flags ^ old_flags;
 9037
 9038	if (gchanges)
 9039		rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC, portid, nlh);
 9040
 9041	if (changes & IFF_UP) {
 9042		if (dev->flags & IFF_UP)
 9043			call_netdevice_notifiers(NETDEV_UP, dev);
 9044		else
 9045			call_netdevice_notifiers(NETDEV_DOWN, dev);
 9046	}
 9047
 9048	if (dev->flags & IFF_UP &&
 9049	    (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
 9050		struct netdev_notifier_change_info change_info = {
 9051			.info = {
 9052				.dev = dev,
 9053			},
 9054			.flags_changed = changes,
 9055		};
 9056
 9057		call_netdevice_notifiers_info(NETDEV_CHANGE, &change_info.info);
 9058	}
 9059}
 9060
 9061/**
 9062 *	dev_change_flags - change device settings
 9063 *	@dev: device
 9064 *	@flags: device state flags
 9065 *	@extack: netlink extended ack
 9066 *
 9067 *	Change settings on device based state flags. The flags are
 9068 *	in the userspace exported format.
 9069 */
 9070int dev_change_flags(struct net_device *dev, unsigned int flags,
 9071		     struct netlink_ext_ack *extack)
 9072{
 9073	int ret;
 9074	unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
 9075
 9076	ret = __dev_change_flags(dev, flags, extack);
 9077	if (ret < 0)
 9078		return ret;
 9079
 9080	changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
 9081	__dev_notify_flags(dev, old_flags, changes, 0, NULL);
 
 
 
 9082	return ret;
 9083}
 9084EXPORT_SYMBOL(dev_change_flags);
 9085
 9086int __dev_set_mtu(struct net_device *dev, int new_mtu)
 9087{
 9088	const struct net_device_ops *ops = dev->netdev_ops;
 9089
 9090	if (ops->ndo_change_mtu)
 9091		return ops->ndo_change_mtu(dev, new_mtu);
 9092
 9093	/* Pairs with all the lockless reads of dev->mtu in the stack */
 9094	WRITE_ONCE(dev->mtu, new_mtu);
 9095	return 0;
 9096}
 9097EXPORT_SYMBOL(__dev_set_mtu);
 9098
 9099int dev_validate_mtu(struct net_device *dev, int new_mtu,
 9100		     struct netlink_ext_ack *extack)
 9101{
 9102	/* MTU must be positive, and in range */
 9103	if (new_mtu < 0 || new_mtu < dev->min_mtu) {
 9104		NL_SET_ERR_MSG(extack, "mtu less than device minimum");
 9105		return -EINVAL;
 9106	}
 9107
 9108	if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) {
 9109		NL_SET_ERR_MSG(extack, "mtu greater than device maximum");
 9110		return -EINVAL;
 9111	}
 9112	return 0;
 9113}
 9114
 9115/**
 9116 *	dev_set_mtu_ext - Change maximum transfer unit
 9117 *	@dev: device
 9118 *	@new_mtu: new transfer unit
 9119 *	@extack: netlink extended ack
 9120 *
 9121 *	Change the maximum transfer size of the network device.
 9122 */
 9123int dev_set_mtu_ext(struct net_device *dev, int new_mtu,
 9124		    struct netlink_ext_ack *extack)
 9125{
 9126	int err, orig_mtu;
 
 9127
 9128	if (new_mtu == dev->mtu)
 9129		return 0;
 9130
 9131	err = dev_validate_mtu(dev, new_mtu, extack);
 9132	if (err)
 9133		return err;
 9134
 9135	if (!netif_device_present(dev))
 9136		return -ENODEV;
 9137
 9138	err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
 9139	err = notifier_to_errno(err);
 9140	if (err)
 9141		return err;
 9142
 9143	orig_mtu = dev->mtu;
 9144	err = __dev_set_mtu(dev, new_mtu);
 9145
 9146	if (!err) {
 9147		err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev,
 9148						   orig_mtu);
 9149		err = notifier_to_errno(err);
 9150		if (err) {
 9151			/* setting mtu back and notifying everyone again,
 9152			 * so that they have a chance to revert changes.
 9153			 */
 9154			__dev_set_mtu(dev, orig_mtu);
 9155			call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev,
 9156						     new_mtu);
 9157		}
 9158	}
 9159	return err;
 9160}
 9161
 9162int dev_set_mtu(struct net_device *dev, int new_mtu)
 9163{
 9164	struct netlink_ext_ack extack;
 9165	int err;
 9166
 9167	memset(&extack, 0, sizeof(extack));
 9168	err = dev_set_mtu_ext(dev, new_mtu, &extack);
 9169	if (err && extack._msg)
 9170		net_err_ratelimited("%s: %s\n", dev->name, extack._msg);
 9171	return err;
 9172}
 9173EXPORT_SYMBOL(dev_set_mtu);
 9174
 9175/**
 9176 *	dev_change_tx_queue_len - Change TX queue length of a netdevice
 9177 *	@dev: device
 9178 *	@new_len: new tx queue length
 9179 */
 9180int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len)
 9181{
 9182	unsigned int orig_len = dev->tx_queue_len;
 9183	int res;
 9184
 9185	if (new_len != (unsigned int)new_len)
 9186		return -ERANGE;
 9187
 9188	if (new_len != orig_len) {
 9189		WRITE_ONCE(dev->tx_queue_len, new_len);
 9190		res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev);
 9191		res = notifier_to_errno(res);
 9192		if (res)
 9193			goto err_rollback;
 9194		res = dev_qdisc_change_tx_queue_len(dev);
 9195		if (res)
 9196			goto err_rollback;
 9197	}
 9198
 9199	return 0;
 9200
 9201err_rollback:
 9202	netdev_err(dev, "refused to change device tx_queue_len\n");
 9203	WRITE_ONCE(dev->tx_queue_len, orig_len);
 9204	return res;
 9205}
 9206
 9207/**
 9208 *	dev_set_group - Change group this device belongs to
 9209 *	@dev: device
 9210 *	@new_group: group this device should belong to
 9211 */
 9212void dev_set_group(struct net_device *dev, int new_group)
 9213{
 9214	dev->group = new_group;
 9215}
 9216
 9217/**
 9218 *	dev_pre_changeaddr_notify - Call NETDEV_PRE_CHANGEADDR.
 9219 *	@dev: device
 9220 *	@addr: new address
 9221 *	@extack: netlink extended ack
 9222 */
 9223int dev_pre_changeaddr_notify(struct net_device *dev, const char *addr,
 9224			      struct netlink_ext_ack *extack)
 9225{
 9226	struct netdev_notifier_pre_changeaddr_info info = {
 9227		.info.dev = dev,
 9228		.info.extack = extack,
 9229		.dev_addr = addr,
 9230	};
 9231	int rc;
 9232
 9233	rc = call_netdevice_notifiers_info(NETDEV_PRE_CHANGEADDR, &info.info);
 9234	return notifier_to_errno(rc);
 9235}
 9236EXPORT_SYMBOL(dev_pre_changeaddr_notify);
 9237
 9238/**
 9239 *	dev_set_mac_address - Change Media Access Control Address
 9240 *	@dev: device
 9241 *	@sa: new address
 9242 *	@extack: netlink extended ack
 9243 *
 9244 *	Change the hardware (MAC) address of the device
 9245 */
 9246int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa,
 9247			struct netlink_ext_ack *extack)
 9248{
 9249	const struct net_device_ops *ops = dev->netdev_ops;
 9250	int err;
 9251
 9252	if (!ops->ndo_set_mac_address)
 9253		return -EOPNOTSUPP;
 9254	if (sa->sa_family != dev->type)
 9255		return -EINVAL;
 9256	if (!netif_device_present(dev))
 9257		return -ENODEV;
 9258	err = dev_pre_changeaddr_notify(dev, sa->sa_data, extack);
 9259	if (err)
 9260		return err;
 9261	if (memcmp(dev->dev_addr, sa->sa_data, dev->addr_len)) {
 9262		err = ops->ndo_set_mac_address(dev, sa);
 9263		if (err)
 9264			return err;
 9265	}
 9266	dev->addr_assign_type = NET_ADDR_SET;
 9267	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
 9268	add_device_randomness(dev->dev_addr, dev->addr_len);
 9269	return 0;
 9270}
 9271EXPORT_SYMBOL(dev_set_mac_address);
 9272
 9273DECLARE_RWSEM(dev_addr_sem);
 9274
 9275int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa,
 9276			     struct netlink_ext_ack *extack)
 9277{
 9278	int ret;
 9279
 9280	down_write(&dev_addr_sem);
 9281	ret = dev_set_mac_address(dev, sa, extack);
 9282	up_write(&dev_addr_sem);
 9283	return ret;
 9284}
 9285EXPORT_SYMBOL(dev_set_mac_address_user);
 9286
 9287int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name)
 9288{
 9289	size_t size = sizeof(sa->sa_data_min);
 9290	struct net_device *dev;
 9291	int ret = 0;
 9292
 9293	down_read(&dev_addr_sem);
 9294	rcu_read_lock();
 9295
 9296	dev = dev_get_by_name_rcu(net, dev_name);
 9297	if (!dev) {
 9298		ret = -ENODEV;
 9299		goto unlock;
 9300	}
 9301	if (!dev->addr_len)
 9302		memset(sa->sa_data, 0, size);
 9303	else
 9304		memcpy(sa->sa_data, dev->dev_addr,
 9305		       min_t(size_t, size, dev->addr_len));
 9306	sa->sa_family = dev->type;
 9307
 9308unlock:
 9309	rcu_read_unlock();
 9310	up_read(&dev_addr_sem);
 9311	return ret;
 9312}
 9313EXPORT_SYMBOL(dev_get_mac_address);
 9314
 9315/**
 9316 *	dev_change_carrier - Change device carrier
 9317 *	@dev: device
 9318 *	@new_carrier: new value
 9319 *
 9320 *	Change device carrier
 9321 */
 9322int dev_change_carrier(struct net_device *dev, bool new_carrier)
 9323{
 9324	const struct net_device_ops *ops = dev->netdev_ops;
 
 9325
 9326	if (!ops->ndo_change_carrier)
 9327		return -EOPNOTSUPP;
 9328	if (!netif_device_present(dev))
 9329		return -ENODEV;
 9330	return ops->ndo_change_carrier(dev, new_carrier);
 9331}
 9332
 9333/**
 9334 *	dev_get_phys_port_id - Get device physical port ID
 9335 *	@dev: device
 9336 *	@ppid: port ID
 9337 *
 9338 *	Get device physical port ID
 9339 */
 9340int dev_get_phys_port_id(struct net_device *dev,
 9341			 struct netdev_phys_item_id *ppid)
 9342{
 9343	const struct net_device_ops *ops = dev->netdev_ops;
 9344
 9345	if (!ops->ndo_get_phys_port_id)
 9346		return -EOPNOTSUPP;
 9347	return ops->ndo_get_phys_port_id(dev, ppid);
 9348}
 9349
 9350/**
 9351 *	dev_get_phys_port_name - Get device physical port name
 9352 *	@dev: device
 9353 *	@name: port name
 9354 *	@len: limit of bytes to copy to name
 9355 *
 9356 *	Get device physical port name
 9357 */
 9358int dev_get_phys_port_name(struct net_device *dev,
 9359			   char *name, size_t len)
 9360{
 9361	const struct net_device_ops *ops = dev->netdev_ops;
 9362	int err;
 9363
 9364	if (ops->ndo_get_phys_port_name) {
 9365		err = ops->ndo_get_phys_port_name(dev, name, len);
 9366		if (err != -EOPNOTSUPP)
 9367			return err;
 9368	}
 9369	return devlink_compat_phys_port_name_get(dev, name, len);
 9370}
 
 9371
 9372/**
 9373 *	dev_get_port_parent_id - Get the device's port parent identifier
 9374 *	@dev: network device
 9375 *	@ppid: pointer to a storage for the port's parent identifier
 9376 *	@recurse: allow/disallow recursion to lower devices
 9377 *
 9378 *	Get the devices's port parent identifier
 9379 */
 9380int dev_get_port_parent_id(struct net_device *dev,
 9381			   struct netdev_phys_item_id *ppid,
 9382			   bool recurse)
 9383{
 9384	const struct net_device_ops *ops = dev->netdev_ops;
 9385	struct netdev_phys_item_id first = { };
 9386	struct net_device *lower_dev;
 9387	struct list_head *iter;
 9388	int err;
 9389
 9390	if (ops->ndo_get_port_parent_id) {
 9391		err = ops->ndo_get_port_parent_id(dev, ppid);
 9392		if (err != -EOPNOTSUPP)
 9393			return err;
 9394	}
 
 
 
 9395
 9396	err = devlink_compat_switch_id_get(dev, ppid);
 9397	if (!recurse || err != -EOPNOTSUPP)
 9398		return err;
 9399
 9400	netdev_for_each_lower_dev(dev, lower_dev, iter) {
 9401		err = dev_get_port_parent_id(lower_dev, ppid, true);
 9402		if (err)
 9403			break;
 9404		if (!first.id_len)
 9405			first = *ppid;
 9406		else if (memcmp(&first, ppid, sizeof(*ppid)))
 9407			return -EOPNOTSUPP;
 9408	}
 
 
 9409
 
 9410	return err;
 9411}
 9412EXPORT_SYMBOL(dev_get_port_parent_id);
 9413
 9414/**
 9415 *	netdev_port_same_parent_id - Indicate if two network devices have
 9416 *	the same port parent identifier
 9417 *	@a: first network device
 9418 *	@b: second network device
 9419 */
 9420bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b)
 9421{
 9422	struct netdev_phys_item_id a_id = { };
 9423	struct netdev_phys_item_id b_id = { };
 9424
 9425	if (dev_get_port_parent_id(a, &a_id, true) ||
 9426	    dev_get_port_parent_id(b, &b_id, true))
 9427		return false;
 9428
 9429	return netdev_phys_item_id_same(&a_id, &b_id);
 9430}
 9431EXPORT_SYMBOL(netdev_port_same_parent_id);
 9432
 9433/**
 9434 *	dev_change_proto_down - set carrier according to proto_down.
 9435 *
 9436 *	@dev: device
 9437 *	@proto_down: new value
 9438 */
 9439int dev_change_proto_down(struct net_device *dev, bool proto_down)
 9440{
 9441	if (!dev->change_proto_down)
 9442		return -EOPNOTSUPP;
 9443	if (!netif_device_present(dev))
 9444		return -ENODEV;
 9445	if (proto_down)
 9446		netif_carrier_off(dev);
 9447	else
 9448		netif_carrier_on(dev);
 9449	WRITE_ONCE(dev->proto_down, proto_down);
 9450	return 0;
 9451}
 9452
 9453/**
 9454 *	dev_change_proto_down_reason - proto down reason
 9455 *
 9456 *	@dev: device
 9457 *	@mask: proto down mask
 9458 *	@value: proto down value
 9459 */
 9460void dev_change_proto_down_reason(struct net_device *dev, unsigned long mask,
 9461				  u32 value)
 9462{
 9463	u32 proto_down_reason;
 9464	int b;
 9465
 9466	if (!mask) {
 9467		proto_down_reason = value;
 9468	} else {
 9469		proto_down_reason = dev->proto_down_reason;
 9470		for_each_set_bit(b, &mask, 32) {
 9471			if (value & (1 << b))
 9472				proto_down_reason |= BIT(b);
 9473			else
 9474				proto_down_reason &= ~BIT(b);
 9475		}
 9476	}
 9477	WRITE_ONCE(dev->proto_down_reason, proto_down_reason);
 9478}
 9479
 9480struct bpf_xdp_link {
 9481	struct bpf_link link;
 9482	struct net_device *dev; /* protected by rtnl_lock, no refcnt held */
 9483	int flags;
 9484};
 9485
 9486static enum bpf_xdp_mode dev_xdp_mode(struct net_device *dev, u32 flags)
 9487{
 9488	if (flags & XDP_FLAGS_HW_MODE)
 9489		return XDP_MODE_HW;
 9490	if (flags & XDP_FLAGS_DRV_MODE)
 9491		return XDP_MODE_DRV;
 9492	if (flags & XDP_FLAGS_SKB_MODE)
 9493		return XDP_MODE_SKB;
 9494	return dev->netdev_ops->ndo_bpf ? XDP_MODE_DRV : XDP_MODE_SKB;
 9495}
 9496
 9497static bpf_op_t dev_xdp_bpf_op(struct net_device *dev, enum bpf_xdp_mode mode)
 9498{
 9499	switch (mode) {
 9500	case XDP_MODE_SKB:
 9501		return generic_xdp_install;
 9502	case XDP_MODE_DRV:
 9503	case XDP_MODE_HW:
 9504		return dev->netdev_ops->ndo_bpf;
 9505	default:
 9506		return NULL;
 9507	}
 9508}
 9509
 9510static struct bpf_xdp_link *dev_xdp_link(struct net_device *dev,
 9511					 enum bpf_xdp_mode mode)
 9512{
 9513	return dev->xdp_state[mode].link;
 9514}
 9515
 9516static struct bpf_prog *dev_xdp_prog(struct net_device *dev,
 9517				     enum bpf_xdp_mode mode)
 9518{
 9519	struct bpf_xdp_link *link = dev_xdp_link(dev, mode);
 9520
 9521	if (link)
 9522		return link->link.prog;
 9523	return dev->xdp_state[mode].prog;
 9524}
 9525
 9526u8 dev_xdp_prog_count(struct net_device *dev)
 9527{
 9528	u8 count = 0;
 9529	int i;
 9530
 9531	for (i = 0; i < __MAX_XDP_MODE; i++)
 9532		if (dev->xdp_state[i].prog || dev->xdp_state[i].link)
 9533			count++;
 9534	return count;
 9535}
 9536EXPORT_SYMBOL_GPL(dev_xdp_prog_count);
 
 9537
 9538int dev_xdp_propagate(struct net_device *dev, struct netdev_bpf *bpf)
 9539{
 9540	if (!dev->netdev_ops->ndo_bpf)
 
 
 
 9541		return -EOPNOTSUPP;
 9542
 9543	if (dev_get_min_mp_channel_count(dev)) {
 9544		NL_SET_ERR_MSG(bpf->extack, "unable to propagate XDP to device using memory provider");
 9545		return -EBUSY;
 9546	}
 9547
 9548	return dev->netdev_ops->ndo_bpf(dev, bpf);
 9549}
 9550EXPORT_SYMBOL_GPL(dev_xdp_propagate);
 9551
 9552u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode)
 9553{
 9554	struct bpf_prog *prog = dev_xdp_prog(dev, mode);
 9555
 9556	return prog ? prog->aux->id : 0;
 9557}
 9558
 9559static void dev_xdp_set_link(struct net_device *dev, enum bpf_xdp_mode mode,
 9560			     struct bpf_xdp_link *link)
 9561{
 9562	dev->xdp_state[mode].link = link;
 9563	dev->xdp_state[mode].prog = NULL;
 9564}
 
 9565
 9566static void dev_xdp_set_prog(struct net_device *dev, enum bpf_xdp_mode mode,
 9567			     struct bpf_prog *prog)
 9568{
 9569	dev->xdp_state[mode].link = NULL;
 9570	dev->xdp_state[mode].prog = prog;
 9571}
 9572
 9573static int dev_xdp_install(struct net_device *dev, enum bpf_xdp_mode mode,
 9574			   bpf_op_t bpf_op, struct netlink_ext_ack *extack,
 9575			   u32 flags, struct bpf_prog *prog)
 9576{
 9577	struct netdev_bpf xdp;
 9578	int err;
 9579
 9580	if (dev_get_min_mp_channel_count(dev)) {
 9581		NL_SET_ERR_MSG(extack, "unable to install XDP to device using memory provider");
 9582		return -EBUSY;
 9583	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 9584
 9585	memset(&xdp, 0, sizeof(xdp));
 9586	xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG;
 9587	xdp.extack = extack;
 9588	xdp.flags = flags;
 9589	xdp.prog = prog;
 9590
 9591	/* Drivers assume refcnt is already incremented (i.e, prog pointer is
 9592	 * "moved" into driver), so they don't increment it on their own, but
 9593	 * they do decrement refcnt when program is detached or replaced.
 9594	 * Given net_device also owns link/prog, we need to bump refcnt here
 9595	 * to prevent drivers from underflowing it.
 9596	 */
 9597	if (prog)
 9598		bpf_prog_inc(prog);
 9599	err = bpf_op(dev, &xdp);
 9600	if (err) {
 9601		if (prog)
 9602			bpf_prog_put(prog);
 9603		return err;
 9604	}
 9605
 9606	if (mode != XDP_MODE_HW)
 9607		bpf_prog_change_xdp(dev_xdp_prog(dev, mode), prog);
 9608
 9609	return 0;
 9610}
 9611
 9612static void dev_xdp_uninstall(struct net_device *dev)
 9613{
 9614	struct bpf_xdp_link *link;
 9615	struct bpf_prog *prog;
 9616	enum bpf_xdp_mode mode;
 9617	bpf_op_t bpf_op;
 9618
 9619	ASSERT_RTNL();
 9620
 9621	for (mode = XDP_MODE_SKB; mode < __MAX_XDP_MODE; mode++) {
 9622		prog = dev_xdp_prog(dev, mode);
 9623		if (!prog)
 9624			continue;
 9625
 9626		bpf_op = dev_xdp_bpf_op(dev, mode);
 9627		if (!bpf_op)
 9628			continue;
 9629
 9630		WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL));
 9631
 9632		/* auto-detach link from net device */
 9633		link = dev_xdp_link(dev, mode);
 9634		if (link)
 9635			link->dev = NULL;
 9636		else
 9637			bpf_prog_put(prog);
 9638
 9639		dev_xdp_set_link(dev, mode, NULL);
 9640	}
 9641}
 
 
 
 
 
 
 
 
 9642
 9643static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack,
 9644			  struct bpf_xdp_link *link, struct bpf_prog *new_prog,
 9645			  struct bpf_prog *old_prog, u32 flags)
 9646{
 9647	unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES);
 9648	struct bpf_prog *cur_prog;
 9649	struct net_device *upper;
 9650	struct list_head *iter;
 9651	enum bpf_xdp_mode mode;
 9652	bpf_op_t bpf_op;
 9653	int err;
 9654
 9655	ASSERT_RTNL();
 
 
 
 9656
 9657	/* either link or prog attachment, never both */
 9658	if (link && (new_prog || old_prog))
 9659		return -EINVAL;
 9660	/* link supports only XDP mode flags */
 9661	if (link && (flags & ~XDP_FLAGS_MODES)) {
 9662		NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment");
 9663		return -EINVAL;
 9664	}
 9665	/* just one XDP mode bit should be set, zero defaults to drv/skb mode */
 9666	if (num_modes > 1) {
 9667		NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set");
 9668		return -EINVAL;
 9669	}
 9670	/* avoid ambiguity if offload + drv/skb mode progs are both loaded */
 9671	if (!num_modes && dev_xdp_prog_count(dev) > 1) {
 9672		NL_SET_ERR_MSG(extack,
 9673			       "More than one program loaded, unset mode is ambiguous");
 9674		return -EINVAL;
 9675	}
 9676	/* old_prog != NULL implies XDP_FLAGS_REPLACE is set */
 9677	if (old_prog && !(flags & XDP_FLAGS_REPLACE)) {
 9678		NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified");
 9679		return -EINVAL;
 9680	}
 
 
 9681
 9682	mode = dev_xdp_mode(dev, flags);
 9683	/* can't replace attached link */
 9684	if (dev_xdp_link(dev, mode)) {
 9685		NL_SET_ERR_MSG(extack, "Can't replace active BPF XDP link");
 9686		return -EBUSY;
 9687	}
 9688
 9689	/* don't allow if an upper device already has a program */
 9690	netdev_for_each_upper_dev_rcu(dev, upper, iter) {
 9691		if (dev_xdp_prog_count(upper) > 0) {
 9692			NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program");
 9693			return -EEXIST;
 9694		}
 9695	}
 9696
 9697	cur_prog = dev_xdp_prog(dev, mode);
 9698	/* can't replace attached prog with link */
 9699	if (link && cur_prog) {
 9700		NL_SET_ERR_MSG(extack, "Can't replace active XDP program with BPF link");
 9701		return -EBUSY;
 9702	}
 9703	if ((flags & XDP_FLAGS_REPLACE) && cur_prog != old_prog) {
 9704		NL_SET_ERR_MSG(extack, "Active program does not match expected");
 9705		return -EEXIST;
 9706	}
 9707
 9708	/* put effective new program into new_prog */
 9709	if (link)
 9710		new_prog = link->link.prog;
 9711
 9712	if (new_prog) {
 9713		bool offload = mode == XDP_MODE_HW;
 9714		enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB
 9715					       ? XDP_MODE_DRV : XDP_MODE_SKB;
 9716
 9717		if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) {
 9718			NL_SET_ERR_MSG(extack, "XDP program already attached");
 9719			return -EBUSY;
 9720		}
 9721		if (!offload && dev_xdp_prog(dev, other_mode)) {
 9722			NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time");
 9723			return -EEXIST;
 9724		}
 9725		if (!offload && bpf_prog_is_offloaded(new_prog->aux)) {
 9726			NL_SET_ERR_MSG(extack, "Using offloaded program without HW_MODE flag is not supported");
 9727			return -EINVAL;
 9728		}
 9729		if (bpf_prog_is_dev_bound(new_prog->aux) && !bpf_offload_dev_match(new_prog, dev)) {
 9730			NL_SET_ERR_MSG(extack, "Program bound to different device");
 9731			return -EINVAL;
 9732		}
 9733		if (bpf_prog_is_dev_bound(new_prog->aux) && mode == XDP_MODE_SKB) {
 9734			NL_SET_ERR_MSG(extack, "Can't attach device-bound programs in generic mode");
 9735			return -EINVAL;
 9736		}
 9737		if (new_prog->expected_attach_type == BPF_XDP_DEVMAP) {
 9738			NL_SET_ERR_MSG(extack, "BPF_XDP_DEVMAP programs can not be attached to a device");
 9739			return -EINVAL;
 9740		}
 9741		if (new_prog->expected_attach_type == BPF_XDP_CPUMAP) {
 9742			NL_SET_ERR_MSG(extack, "BPF_XDP_CPUMAP programs can not be attached to a device");
 9743			return -EINVAL;
 9744		}
 9745	}
 9746
 9747	/* don't call drivers if the effective program didn't change */
 9748	if (new_prog != cur_prog) {
 9749		bpf_op = dev_xdp_bpf_op(dev, mode);
 9750		if (!bpf_op) {
 9751			NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode");
 9752			return -EOPNOTSUPP;
 
 
 
 
 
 9753		}
 
 9754
 9755		err = dev_xdp_install(dev, mode, bpf_op, extack, flags, new_prog);
 9756		if (err)
 9757			return err;
 9758	}
 9759
 9760	if (link)
 9761		dev_xdp_set_link(dev, mode, link);
 9762	else
 9763		dev_xdp_set_prog(dev, mode, new_prog);
 9764	if (cur_prog)
 9765		bpf_prog_put(cur_prog);
 9766
 9767	return 0;
 9768}
 9769
 9770static int dev_xdp_attach_link(struct net_device *dev,
 9771			       struct netlink_ext_ack *extack,
 9772			       struct bpf_xdp_link *link)
 9773{
 9774	return dev_xdp_attach(dev, extack, link, NULL, NULL, link->flags);
 9775}
 9776
 9777static int dev_xdp_detach_link(struct net_device *dev,
 9778			       struct netlink_ext_ack *extack,
 9779			       struct bpf_xdp_link *link)
 9780{
 9781	enum bpf_xdp_mode mode;
 9782	bpf_op_t bpf_op;
 9783
 9784	ASSERT_RTNL();
 9785
 9786	mode = dev_xdp_mode(dev, link->flags);
 9787	if (dev_xdp_link(dev, mode) != link)
 9788		return -EINVAL;
 9789
 9790	bpf_op = dev_xdp_bpf_op(dev, mode);
 9791	WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL));
 9792	dev_xdp_set_link(dev, mode, NULL);
 9793	return 0;
 9794}
 9795
 9796static void bpf_xdp_link_release(struct bpf_link *link)
 9797{
 9798	struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 9799
 9800	rtnl_lock();
 
 
 
 
 
 
 
 9801
 9802	/* if racing with net_device's tear down, xdp_link->dev might be
 9803	 * already NULL, in which case link was already auto-detached
 9804	 */
 9805	if (xdp_link->dev) {
 9806		WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link));
 9807		xdp_link->dev = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 9808	}
 9809
 9810	rtnl_unlock();
 9811}
 9812
 9813static int bpf_xdp_link_detach(struct bpf_link *link)
 9814{
 9815	bpf_xdp_link_release(link);
 9816	return 0;
 9817}
 9818
 9819static void bpf_xdp_link_dealloc(struct bpf_link *link)
 9820{
 9821	struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
 9822
 9823	kfree(xdp_link);
 9824}
 9825
 9826static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link,
 9827				     struct seq_file *seq)
 9828{
 9829	struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
 9830	u32 ifindex = 0;
 9831
 9832	rtnl_lock();
 9833	if (xdp_link->dev)
 9834		ifindex = xdp_link->dev->ifindex;
 9835	rtnl_unlock();
 9836
 9837	seq_printf(seq, "ifindex:\t%u\n", ifindex);
 9838}
 9839
 9840static int bpf_xdp_link_fill_link_info(const struct bpf_link *link,
 9841				       struct bpf_link_info *info)
 9842{
 9843	struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
 9844	u32 ifindex = 0;
 9845
 9846	rtnl_lock();
 9847	if (xdp_link->dev)
 9848		ifindex = xdp_link->dev->ifindex;
 9849	rtnl_unlock();
 9850
 9851	info->xdp.ifindex = ifindex;
 9852	return 0;
 9853}
 9854
 9855static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog,
 9856			       struct bpf_prog *old_prog)
 
 
 
 
 
 
 
 9857{
 9858	struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
 9859	enum bpf_xdp_mode mode;
 9860	bpf_op_t bpf_op;
 9861	int err = 0;
 9862
 9863	rtnl_lock();
 9864
 9865	/* link might have been auto-released already, so fail */
 9866	if (!xdp_link->dev) {
 9867		err = -ENOLINK;
 9868		goto out_unlock;
 9869	}
 9870
 9871	if (old_prog && link->prog != old_prog) {
 9872		err = -EPERM;
 9873		goto out_unlock;
 9874	}
 9875	old_prog = link->prog;
 9876	if (old_prog->type != new_prog->type ||
 9877	    old_prog->expected_attach_type != new_prog->expected_attach_type) {
 9878		err = -EINVAL;
 9879		goto out_unlock;
 9880	}
 9881
 9882	if (old_prog == new_prog) {
 9883		/* no-op, don't disturb drivers */
 9884		bpf_prog_put(new_prog);
 9885		goto out_unlock;
 9886	}
 9887
 9888	mode = dev_xdp_mode(xdp_link->dev, xdp_link->flags);
 9889	bpf_op = dev_xdp_bpf_op(xdp_link->dev, mode);
 9890	err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL,
 9891			      xdp_link->flags, new_prog);
 9892	if (err)
 9893		goto out_unlock;
 9894
 9895	old_prog = xchg(&link->prog, new_prog);
 9896	bpf_prog_put(old_prog);
 9897
 9898out_unlock:
 9899	rtnl_unlock();
 9900	return err;
 9901}
 9902
 9903static const struct bpf_link_ops bpf_xdp_link_lops = {
 9904	.release = bpf_xdp_link_release,
 9905	.dealloc = bpf_xdp_link_dealloc,
 9906	.detach = bpf_xdp_link_detach,
 9907	.show_fdinfo = bpf_xdp_link_show_fdinfo,
 9908	.fill_link_info = bpf_xdp_link_fill_link_info,
 9909	.update_prog = bpf_xdp_link_update,
 9910};
 9911
 9912int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
 9913{
 9914	struct net *net = current->nsproxy->net_ns;
 9915	struct bpf_link_primer link_primer;
 9916	struct netlink_ext_ack extack = {};
 9917	struct bpf_xdp_link *link;
 9918	struct net_device *dev;
 9919	int err, fd;
 9920
 9921	rtnl_lock();
 9922	dev = dev_get_by_index(net, attr->link_create.target_ifindex);
 9923	if (!dev) {
 9924		rtnl_unlock();
 9925		return -EINVAL;
 9926	}
 9927
 9928	link = kzalloc(sizeof(*link), GFP_USER);
 9929	if (!link) {
 9930		err = -ENOMEM;
 9931		goto unlock;
 9932	}
 9933
 9934	bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog);
 9935	link->dev = dev;
 9936	link->flags = attr->link_create.flags;
 9937
 9938	err = bpf_link_prime(&link->link, &link_primer);
 9939	if (err) {
 9940		kfree(link);
 9941		goto unlock;
 9942	}
 9943
 9944	err = dev_xdp_attach_link(dev, &extack, link);
 9945	rtnl_unlock();
 9946
 9947	if (err) {
 9948		link->dev = NULL;
 9949		bpf_link_cleanup(&link_primer);
 9950		trace_bpf_xdp_link_attach_failed(extack._msg);
 9951		goto out_put_dev;
 9952	}
 9953
 9954	fd = bpf_link_settle(&link_primer);
 9955	/* link itself doesn't hold dev's refcnt to not complicate shutdown */
 9956	dev_put(dev);
 9957	return fd;
 9958
 9959unlock:
 9960	rtnl_unlock();
 9961
 9962out_put_dev:
 9963	dev_put(dev);
 9964	return err;
 9965}
 9966
 9967/**
 9968 *	dev_change_xdp_fd - set or clear a bpf program for a device rx path
 9969 *	@dev: device
 9970 *	@extack: netlink extended ack
 9971 *	@fd: new program fd or negative value to clear
 9972 *	@expected_fd: old program fd that userspace expects to replace or clear
 9973 *	@flags: xdp-related flags
 9974 *
 9975 *	Set or clear a bpf program for a device
 9976 */
 9977int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
 9978		      int fd, int expected_fd, u32 flags)
 9979{
 9980	enum bpf_xdp_mode mode = dev_xdp_mode(dev, flags);
 9981	struct bpf_prog *new_prog = NULL, *old_prog = NULL;
 9982	int err;
 9983
 
 9984	ASSERT_RTNL();
 9985
 9986	if (fd >= 0) {
 9987		new_prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP,
 9988						 mode != XDP_MODE_SKB);
 9989		if (IS_ERR(new_prog))
 9990			return PTR_ERR(new_prog);
 9991	}
 9992
 9993	if (expected_fd >= 0) {
 9994		old_prog = bpf_prog_get_type_dev(expected_fd, BPF_PROG_TYPE_XDP,
 9995						 mode != XDP_MODE_SKB);
 9996		if (IS_ERR(old_prog)) {
 9997			err = PTR_ERR(old_prog);
 9998			old_prog = NULL;
 9999			goto err_out;
10000		}
 
 
10001	}
10002
10003	err = dev_xdp_attach(dev, extack, NULL, new_prog, old_prog, flags);
10004
10005err_out:
10006	if (err && new_prog)
10007		bpf_prog_put(new_prog);
10008	if (old_prog)
10009		bpf_prog_put(old_prog);
10010	return err;
10011}
10012
10013u32 dev_get_min_mp_channel_count(const struct net_device *dev)
10014{
10015	int i;
10016
10017	ASSERT_RTNL();
 
 
10018
10019	for (i = dev->real_num_rx_queues - 1; i >= 0; i--)
10020		if (dev->_rx[i].mp_params.mp_priv)
10021			/* The channel count is the idx plus 1. */
10022			return i + 1;
10023
10024	return 0;
10025}
10026
10027/**
10028 * dev_index_reserve() - allocate an ifindex in a namespace
10029 * @net: the applicable net namespace
10030 * @ifindex: requested ifindex, pass %0 to get one allocated
10031 *
10032 * Allocate a ifindex for a new device. Caller must either use the ifindex
10033 * to store the device (via list_netdevice()) or call dev_index_release()
10034 * to give the index up.
10035 *
10036 * Return: a suitable unique value for a new device interface number or -errno.
10037 */
10038static int dev_index_reserve(struct net *net, u32 ifindex)
10039{
10040	int err;
10041
10042	if (ifindex > INT_MAX) {
10043		DEBUG_NET_WARN_ON_ONCE(1);
10044		return -EINVAL;
10045	}
10046
10047	if (!ifindex)
10048		err = xa_alloc_cyclic(&net->dev_by_index, &ifindex, NULL,
10049				      xa_limit_31b, &net->ifindex, GFP_KERNEL);
10050	else
10051		err = xa_insert(&net->dev_by_index, ifindex, NULL, GFP_KERNEL);
10052	if (err < 0)
10053		return err;
10054
10055	return ifindex;
10056}
 
10057
10058static void dev_index_release(struct net *net, int ifindex)
10059{
10060	/* Expect only unused indexes, unlist_netdevice() removes the used */
10061	WARN_ON(xa_erase(&net->dev_by_index, ifindex));
10062}
10063
10064/* Delayed registration/unregisteration */
10065LIST_HEAD(net_todo_list);
10066DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
10067atomic_t dev_unreg_count = ATOMIC_INIT(0);
10068
10069static void net_set_todo(struct net_device *dev)
10070{
10071	list_add_tail(&dev->todo_list, &net_todo_list);
10072}
10073
10074static netdev_features_t netdev_sync_upper_features(struct net_device *lower,
10075	struct net_device *upper, netdev_features_t features)
10076{
10077	netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
10078	netdev_features_t feature;
10079	int feature_bit;
10080
10081	for_each_netdev_feature(upper_disables, feature_bit) {
10082		feature = __NETIF_F_BIT(feature_bit);
10083		if (!(upper->wanted_features & feature)
10084		    && (features & feature)) {
10085			netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n",
10086				   &feature, upper->name);
10087			features &= ~feature;
10088		}
10089	}
10090
10091	return features;
10092}
 
10093
10094static void netdev_sync_lower_features(struct net_device *upper,
10095	struct net_device *lower, netdev_features_t features)
10096{
10097	netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
10098	netdev_features_t feature;
10099	int feature_bit;
10100
10101	for_each_netdev_feature(upper_disables, feature_bit) {
10102		feature = __NETIF_F_BIT(feature_bit);
10103		if (!(features & feature) && (lower->features & feature)) {
10104			netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n",
10105				   &feature, lower->name);
10106			lower->wanted_features &= ~feature;
10107			__netdev_update_features(lower);
10108
10109			if (unlikely(lower->features & feature))
10110				netdev_WARN(upper, "failed to disable %pNF on %s!\n",
10111					    &feature, lower->name);
10112			else
10113				netdev_features_change(lower);
10114		}
10115	}
10116}
10117
10118static bool netdev_has_ip_or_hw_csum(netdev_features_t features)
10119{
10120	netdev_features_t ip_csum_mask = NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
10121	bool ip_csum = (features & ip_csum_mask) == ip_csum_mask;
10122	bool hw_csum = features & NETIF_F_HW_CSUM;
10123
10124	return ip_csum || hw_csum;
 
 
10125}
10126
10127static netdev_features_t netdev_fix_features(struct net_device *dev,
10128	netdev_features_t features)
10129{
10130	/* Fix illegal checksum combinations */
10131	if ((features & NETIF_F_HW_CSUM) &&
10132	    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
10133		netdev_warn(dev, "mixed HW and IP checksum settings.\n");
10134		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
10135	}
10136
10137	/* TSO requires that SG is present as well. */
10138	if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
10139		netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
10140		features &= ~NETIF_F_ALL_TSO;
10141	}
10142
10143	if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
10144					!(features & NETIF_F_IP_CSUM)) {
10145		netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
10146		features &= ~NETIF_F_TSO;
10147		features &= ~NETIF_F_TSO_ECN;
 
10148	}
10149
10150	if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
10151					 !(features & NETIF_F_IPV6_CSUM)) {
10152		netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
10153		features &= ~NETIF_F_TSO6;
10154	}
10155
10156	/* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */
10157	if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO))
10158		features &= ~NETIF_F_TSO_MANGLEID;
10159
10160	/* TSO ECN requires that TSO is present as well. */
10161	if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
10162		features &= ~NETIF_F_TSO_ECN;
10163
10164	/* Software GSO depends on SG. */
10165	if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
10166		netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
10167		features &= ~NETIF_F_GSO;
10168	}
10169
10170	/* GSO partial features require GSO partial be set */
10171	if ((features & dev->gso_partial_features) &&
10172	    !(features & NETIF_F_GSO_PARTIAL)) {
10173		netdev_dbg(dev,
10174			   "Dropping partially supported GSO features since no GSO partial.\n");
10175		features &= ~dev->gso_partial_features;
10176	}
10177
10178	if (!(features & NETIF_F_RXCSUM)) {
10179		/* NETIF_F_GRO_HW implies doing RXCSUM since every packet
10180		 * successfully merged by hardware must also have the
10181		 * checksum verified by hardware.  If the user does not
10182		 * want to enable RXCSUM, logically, we should disable GRO_HW.
10183		 */
10184		if (features & NETIF_F_GRO_HW) {
10185			netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n");
10186			features &= ~NETIF_F_GRO_HW;
10187		}
10188	}
10189
10190	/* LRO/HW-GRO features cannot be combined with RX-FCS */
10191	if (features & NETIF_F_RXFCS) {
10192		if (features & NETIF_F_LRO) {
10193			netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n");
10194			features &= ~NETIF_F_LRO;
10195		}
10196
10197		if (features & NETIF_F_GRO_HW) {
10198			netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n");
10199			features &= ~NETIF_F_GRO_HW;
10200		}
10201	}
10202
10203	if ((features & NETIF_F_GRO_HW) && (features & NETIF_F_LRO)) {
10204		netdev_dbg(dev, "Dropping LRO feature since HW-GRO is requested.\n");
10205		features &= ~NETIF_F_LRO;
10206	}
10207
10208	if ((features & NETIF_F_HW_TLS_TX) && !netdev_has_ip_or_hw_csum(features)) {
10209		netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n");
10210		features &= ~NETIF_F_HW_TLS_TX;
10211	}
10212
10213	if ((features & NETIF_F_HW_TLS_RX) && !(features & NETIF_F_RXCSUM)) {
10214		netdev_dbg(dev, "Dropping TLS RX HW offload feature since no RXCSUM feature.\n");
10215		features &= ~NETIF_F_HW_TLS_RX;
10216	}
10217
10218	if ((features & NETIF_F_GSO_UDP_L4) && !netdev_has_ip_or_hw_csum(features)) {
10219		netdev_dbg(dev, "Dropping USO feature since no CSUM feature.\n");
10220		features &= ~NETIF_F_GSO_UDP_L4;
10221	}
10222
10223	return features;
10224}
10225
10226int __netdev_update_features(struct net_device *dev)
10227{
10228	struct net_device *upper, *lower;
10229	netdev_features_t features;
10230	struct list_head *iter;
10231	int err = -1;
10232
10233	ASSERT_RTNL();
10234
10235	features = netdev_get_wanted_features(dev);
10236
10237	if (dev->netdev_ops->ndo_fix_features)
10238		features = dev->netdev_ops->ndo_fix_features(dev, features);
10239
10240	/* driver might be less strict about feature dependencies */
10241	features = netdev_fix_features(dev, features);
10242
10243	/* some features can't be enabled if they're off on an upper device */
10244	netdev_for_each_upper_dev_rcu(dev, upper, iter)
10245		features = netdev_sync_upper_features(dev, upper, features);
10246
10247	if (dev->features == features)
10248		goto sync_lower;
10249
10250	netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
10251		&dev->features, &features);
10252
10253	if (dev->netdev_ops->ndo_set_features)
10254		err = dev->netdev_ops->ndo_set_features(dev, features);
10255	else
10256		err = 0;
10257
10258	if (unlikely(err < 0)) {
10259		netdev_err(dev,
10260			"set_features() failed (%d); wanted %pNF, left %pNF\n",
10261			err, &features, &dev->features);
10262		/* return non-0 since some features might have changed and
10263		 * it's better to fire a spurious notification than miss it
10264		 */
10265		return -1;
10266	}
10267
10268sync_lower:
10269	/* some features must be disabled on lower devices when disabled
10270	 * on an upper device (think: bonding master or bridge)
10271	 */
10272	netdev_for_each_lower_dev(dev, lower, iter)
10273		netdev_sync_lower_features(dev, lower, features);
10274
10275	if (!err) {
10276		netdev_features_t diff = features ^ dev->features;
10277
10278		if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) {
10279			/* udp_tunnel_{get,drop}_rx_info both need
10280			 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the
10281			 * device, or they won't do anything.
10282			 * Thus we need to update dev->features
10283			 * *before* calling udp_tunnel_get_rx_info,
10284			 * but *after* calling udp_tunnel_drop_rx_info.
10285			 */
10286			if (features & NETIF_F_RX_UDP_TUNNEL_PORT) {
10287				dev->features = features;
10288				udp_tunnel_get_rx_info(dev);
10289			} else {
10290				udp_tunnel_drop_rx_info(dev);
10291			}
10292		}
10293
10294		if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) {
10295			if (features & NETIF_F_HW_VLAN_CTAG_FILTER) {
10296				dev->features = features;
10297				err |= vlan_get_rx_ctag_filter_info(dev);
10298			} else {
10299				vlan_drop_rx_ctag_filter_info(dev);
10300			}
10301		}
10302
10303		if (diff & NETIF_F_HW_VLAN_STAG_FILTER) {
10304			if (features & NETIF_F_HW_VLAN_STAG_FILTER) {
10305				dev->features = features;
10306				err |= vlan_get_rx_stag_filter_info(dev);
10307			} else {
10308				vlan_drop_rx_stag_filter_info(dev);
10309			}
10310		}
10311
10312		dev->features = features;
10313	}
10314
10315	return err < 0 ? 0 : 1;
10316}
10317
10318/**
10319 *	netdev_update_features - recalculate device features
10320 *	@dev: the device to check
10321 *
10322 *	Recalculate dev->features set and send notifications if it
10323 *	has changed. Should be called after driver or hardware dependent
10324 *	conditions might have changed that influence the features.
10325 */
10326void netdev_update_features(struct net_device *dev)
10327{
10328	if (__netdev_update_features(dev))
10329		netdev_features_change(dev);
10330}
10331EXPORT_SYMBOL(netdev_update_features);
10332
10333/**
10334 *	netdev_change_features - recalculate device features
10335 *	@dev: the device to check
10336 *
10337 *	Recalculate dev->features set and send notifications even
10338 *	if they have not changed. Should be called instead of
10339 *	netdev_update_features() if also dev->vlan_features might
10340 *	have changed to allow the changes to be propagated to stacked
10341 *	VLAN devices.
10342 */
10343void netdev_change_features(struct net_device *dev)
10344{
10345	__netdev_update_features(dev);
10346	netdev_features_change(dev);
10347}
10348EXPORT_SYMBOL(netdev_change_features);
10349
10350/**
10351 *	netif_stacked_transfer_operstate -	transfer operstate
10352 *	@rootdev: the root or lower level device to transfer state from
10353 *	@dev: the device to transfer operstate to
10354 *
10355 *	Transfer operational state from root to device. This is normally
10356 *	called when a stacking relationship exists between the root
10357 *	device and the device(a leaf device).
10358 */
10359void netif_stacked_transfer_operstate(const struct net_device *rootdev,
10360					struct net_device *dev)
10361{
10362	if (rootdev->operstate == IF_OPER_DORMANT)
10363		netif_dormant_on(dev);
10364	else
10365		netif_dormant_off(dev);
10366
10367	if (rootdev->operstate == IF_OPER_TESTING)
10368		netif_testing_on(dev);
10369	else
10370		netif_testing_off(dev);
10371
10372	if (netif_carrier_ok(rootdev))
10373		netif_carrier_on(dev);
10374	else
10375		netif_carrier_off(dev);
10376}
10377EXPORT_SYMBOL(netif_stacked_transfer_operstate);
10378
 
10379static int netif_alloc_rx_queues(struct net_device *dev)
10380{
10381	unsigned int i, count = dev->num_rx_queues;
10382	struct netdev_rx_queue *rx;
10383	size_t sz = count * sizeof(*rx);
10384	int err = 0;
10385
10386	BUG_ON(count < 1);
10387
10388	rx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);
10389	if (!rx)
 
10390		return -ENOMEM;
10391
10392	dev->_rx = rx;
10393
10394	for (i = 0; i < count; i++) {
10395		rx[i].dev = dev;
10396
10397		/* XDP RX-queue setup */
10398		err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i, 0);
10399		if (err < 0)
10400			goto err_rxq_info;
10401	}
10402	return 0;
10403
10404err_rxq_info:
10405	/* Rollback successful reg's and free other resources */
10406	while (i--)
10407		xdp_rxq_info_unreg(&rx[i].xdp_rxq);
10408	kvfree(dev->_rx);
10409	dev->_rx = NULL;
10410	return err;
10411}
10412
10413static void netif_free_rx_queues(struct net_device *dev)
10414{
10415	unsigned int i, count = dev->num_rx_queues;
10416
10417	/* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */
10418	if (!dev->_rx)
10419		return;
10420
10421	for (i = 0; i < count; i++)
10422		xdp_rxq_info_unreg(&dev->_rx[i].xdp_rxq);
10423
10424	kvfree(dev->_rx);
10425}
 
10426
10427static void netdev_init_one_queue(struct net_device *dev,
10428				  struct netdev_queue *queue, void *_unused)
10429{
10430	/* Initialize queue lock */
10431	spin_lock_init(&queue->_xmit_lock);
10432	netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
10433	queue->xmit_lock_owner = -1;
10434	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
10435	queue->dev = dev;
10436#ifdef CONFIG_BQL
10437	dql_init(&queue->dql, HZ);
10438#endif
10439}
10440
10441static void netif_free_tx_queues(struct net_device *dev)
10442{
10443	kvfree(dev->_tx);
10444}
10445
10446static int netif_alloc_netdev_queues(struct net_device *dev)
10447{
10448	unsigned int count = dev->num_tx_queues;
10449	struct netdev_queue *tx;
10450	size_t sz = count * sizeof(*tx);
10451
10452	if (count < 1 || count > 0xffff)
10453		return -EINVAL;
10454
10455	tx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);
10456	if (!tx)
 
 
10457		return -ENOMEM;
10458
10459	dev->_tx = tx;
10460
10461	netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
10462	spin_lock_init(&dev->tx_global_lock);
10463
10464	return 0;
10465}
10466
10467void netif_tx_stop_all_queues(struct net_device *dev)
10468{
10469	unsigned int i;
10470
10471	for (i = 0; i < dev->num_tx_queues; i++) {
10472		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
10473
10474		netif_tx_stop_queue(txq);
10475	}
10476}
10477EXPORT_SYMBOL(netif_tx_stop_all_queues);
10478
10479static int netdev_do_alloc_pcpu_stats(struct net_device *dev)
10480{
10481	void __percpu *v;
10482
10483	/* Drivers implementing ndo_get_peer_dev must support tstat
10484	 * accounting, so that skb_do_redirect() can bump the dev's
10485	 * RX stats upon network namespace switch.
10486	 */
10487	if (dev->netdev_ops->ndo_get_peer_dev &&
10488	    dev->pcpu_stat_type != NETDEV_PCPU_STAT_TSTATS)
10489		return -EOPNOTSUPP;
10490
10491	switch (dev->pcpu_stat_type) {
10492	case NETDEV_PCPU_STAT_NONE:
10493		return 0;
10494	case NETDEV_PCPU_STAT_LSTATS:
10495		v = dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats);
10496		break;
10497	case NETDEV_PCPU_STAT_TSTATS:
10498		v = dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
10499		break;
10500	case NETDEV_PCPU_STAT_DSTATS:
10501		v = dev->dstats = netdev_alloc_pcpu_stats(struct pcpu_dstats);
10502		break;
10503	default:
10504		return -EINVAL;
10505	}
10506
10507	return v ? 0 : -ENOMEM;
10508}
10509
10510static void netdev_do_free_pcpu_stats(struct net_device *dev)
10511{
10512	switch (dev->pcpu_stat_type) {
10513	case NETDEV_PCPU_STAT_NONE:
10514		return;
10515	case NETDEV_PCPU_STAT_LSTATS:
10516		free_percpu(dev->lstats);
10517		break;
10518	case NETDEV_PCPU_STAT_TSTATS:
10519		free_percpu(dev->tstats);
10520		break;
10521	case NETDEV_PCPU_STAT_DSTATS:
10522		free_percpu(dev->dstats);
10523		break;
10524	}
10525}
10526
10527static void netdev_free_phy_link_topology(struct net_device *dev)
10528{
10529	struct phy_link_topology *topo = dev->link_topo;
10530
10531	if (IS_ENABLED(CONFIG_PHYLIB) && topo) {
10532		xa_destroy(&topo->phys);
10533		kfree(topo);
10534		dev->link_topo = NULL;
10535	}
10536}
10537
10538/**
10539 * register_netdevice() - register a network device
10540 * @dev: device to register
10541 *
10542 * Take a prepared network device structure and make it externally accessible.
10543 * A %NETDEV_REGISTER message is sent to the netdev notifier chain.
10544 * Callers must hold the rtnl lock - you may want register_netdev()
10545 * instead of this.
 
 
 
 
 
 
 
10546 */
 
10547int register_netdevice(struct net_device *dev)
10548{
10549	int ret;
10550	struct net *net = dev_net(dev);
10551
10552	BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE <
10553		     NETDEV_FEATURE_COUNT);
10554	BUG_ON(dev_boot_phase);
10555	ASSERT_RTNL();
10556
10557	might_sleep();
10558
10559	/* When net_device's are persistent, this will be fatal. */
10560	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
10561	BUG_ON(!net);
10562
10563	ret = ethtool_check_ops(dev->ethtool_ops);
10564	if (ret)
10565		return ret;
10566
10567	/* rss ctx ID 0 is reserved for the default context, start from 1 */
10568	xa_init_flags(&dev->ethtool->rss_ctx, XA_FLAGS_ALLOC1);
10569	mutex_init(&dev->ethtool->rss_lock);
10570
10571	spin_lock_init(&dev->addr_list_lock);
10572	netdev_set_addr_lockdep_class(dev);
10573
10574	ret = dev_get_valid_name(net, dev, dev->name);
10575	if (ret < 0)
10576		goto out;
10577
10578	ret = -ENOMEM;
10579	dev->name_node = netdev_name_node_head_alloc(dev);
10580	if (!dev->name_node)
10581		goto out;
10582
10583	/* Init, if this function is available */
10584	if (dev->netdev_ops->ndo_init) {
10585		ret = dev->netdev_ops->ndo_init(dev);
10586		if (ret) {
10587			if (ret > 0)
10588				ret = -EIO;
10589			goto err_free_name;
10590		}
10591	}
10592
10593	if (((dev->hw_features | dev->features) &
10594	     NETIF_F_HW_VLAN_CTAG_FILTER) &&
10595	    (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
10596	     !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
10597		netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
10598		ret = -EINVAL;
10599		goto err_uninit;
10600	}
10601
10602	ret = netdev_do_alloc_pcpu_stats(dev);
10603	if (ret)
10604		goto err_uninit;
10605
10606	ret = dev_index_reserve(net, dev->ifindex);
10607	if (ret < 0)
10608		goto err_free_pcpu;
10609	dev->ifindex = ret;
10610
10611	/* Transfer changeable features to wanted_features and enable
10612	 * software offloads (GSO and GRO).
10613	 */
10614	dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF);
10615	dev->features |= NETIF_F_SOFT_FEATURES;
10616
10617	if (dev->udp_tunnel_nic_info) {
10618		dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT;
10619		dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT;
10620	}
10621
10622	dev->wanted_features = dev->features & dev->hw_features;
10623
10624	if (!(dev->flags & IFF_LOOPBACK))
10625		dev->hw_features |= NETIF_F_NOCACHE_COPY;
10626
10627	/* If IPv4 TCP segmentation offload is supported we should also
10628	 * allow the device to enable segmenting the frame with the option
10629	 * of ignoring a static IP ID value.  This doesn't enable the
10630	 * feature itself but allows the user to enable it later.
10631	 */
10632	if (dev->hw_features & NETIF_F_TSO)
10633		dev->hw_features |= NETIF_F_TSO_MANGLEID;
10634	if (dev->vlan_features & NETIF_F_TSO)
10635		dev->vlan_features |= NETIF_F_TSO_MANGLEID;
10636	if (dev->mpls_features & NETIF_F_TSO)
10637		dev->mpls_features |= NETIF_F_TSO_MANGLEID;
10638	if (dev->hw_enc_features & NETIF_F_TSO)
10639		dev->hw_enc_features |= NETIF_F_TSO_MANGLEID;
10640
10641	/* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
10642	 */
10643	dev->vlan_features |= NETIF_F_HIGHDMA;
10644
10645	/* Make NETIF_F_SG inheritable to tunnel devices.
10646	 */
10647	dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL;
10648
10649	/* Make NETIF_F_SG inheritable to MPLS.
10650	 */
10651	dev->mpls_features |= NETIF_F_SG;
10652
10653	ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
10654	ret = notifier_to_errno(ret);
10655	if (ret)
10656		goto err_ifindex_release;
10657
10658	ret = netdev_register_kobject(dev);
10659
10660	WRITE_ONCE(dev->reg_state, ret ? NETREG_UNREGISTERED : NETREG_REGISTERED);
10661
10662	if (ret)
10663		goto err_uninit_notify;
 
10664
10665	__netdev_update_features(dev);
10666
10667	/*
10668	 *	Default initial state at registry is that the
10669	 *	device is present.
10670	 */
10671
10672	set_bit(__LINK_STATE_PRESENT, &dev->state);
10673
10674	linkwatch_init_dev(dev);
10675
10676	dev_init_scheduler(dev);
10677
10678	netdev_hold(dev, &dev->dev_registered_tracker, GFP_KERNEL);
10679	list_netdevice(dev);
10680
10681	add_device_randomness(dev->dev_addr, dev->addr_len);
10682
10683	/* If the device has permanent device address, driver should
10684	 * set dev_addr and also addr_assign_type should be set to
10685	 * NET_ADDR_PERM (default value).
10686	 */
10687	if (dev->addr_assign_type == NET_ADDR_PERM)
10688		memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
10689
10690	/* Notify protocols, that a new device appeared. */
10691	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
10692	ret = notifier_to_errno(ret);
10693	if (ret) {
10694		/* Expect explicit free_netdev() on failure */
10695		dev->needs_free_netdev = false;
10696		unregister_netdevice_queue(dev, NULL);
10697		goto out;
10698	}
10699	/*
10700	 *	Prevent userspace races by waiting until the network
10701	 *	device is fully setup before sending notifications.
10702	 */
10703	if (!dev->rtnl_link_ops ||
10704	    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
10705		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL);
10706
10707out:
10708	return ret;
10709
10710err_uninit_notify:
10711	call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev);
10712err_ifindex_release:
10713	dev_index_release(net, dev->ifindex);
10714err_free_pcpu:
10715	netdev_do_free_pcpu_stats(dev);
10716err_uninit:
10717	if (dev->netdev_ops->ndo_uninit)
10718		dev->netdev_ops->ndo_uninit(dev);
10719	if (dev->priv_destructor)
10720		dev->priv_destructor(dev);
10721err_free_name:
10722	netdev_name_node_free(dev->name_node);
10723	goto out;
10724}
10725EXPORT_SYMBOL(register_netdevice);
10726
10727/* Initialize the core of a dummy net device.
10728 * This is useful if you are calling this function after alloc_netdev(),
10729 * since it does not memset the net_device fields.
 
 
 
 
 
 
10730 */
10731static void init_dummy_netdev_core(struct net_device *dev)
10732{
 
 
 
 
 
 
 
10733	/* make sure we BUG if trying to hit standard
10734	 * register/unregister code path
10735	 */
10736	dev->reg_state = NETREG_DUMMY;
10737
10738	/* NAPI wants this */
10739	INIT_LIST_HEAD(&dev->napi_list);
10740
10741	/* a dummy interface is started by default */
10742	set_bit(__LINK_STATE_PRESENT, &dev->state);
10743	set_bit(__LINK_STATE_START, &dev->state);
10744
10745	/* napi_busy_loop stats accounting wants this */
10746	dev_net_set(dev, &init_net);
10747
10748	/* Note : We dont allocate pcpu_refcnt for dummy devices,
10749	 * because users of this 'device' dont need to change
10750	 * its refcount.
10751	 */
10752}
10753
10754/**
10755 *	init_dummy_netdev	- init a dummy network device for NAPI
10756 *	@dev: device to init
10757 *
10758 *	This takes a network device structure and initializes the minimum
10759 *	amount of fields so it can be used to schedule NAPI polls without
10760 *	registering a full blown interface. This is to be used by drivers
10761 *	that need to tie several hardware interfaces to a single NAPI
10762 *	poll scheduler due to HW limitations.
10763 */
10764void init_dummy_netdev(struct net_device *dev)
10765{
10766	/* Clear everything. Note we don't initialize spinlocks
10767	 * as they aren't supposed to be taken by any of the
10768	 * NAPI code and this dummy netdev is supposed to be
10769	 * only ever used for NAPI polls
10770	 */
10771	memset(dev, 0, sizeof(struct net_device));
10772	init_dummy_netdev_core(dev);
10773}
10774EXPORT_SYMBOL_GPL(init_dummy_netdev);
10775
 
10776/**
10777 *	register_netdev	- register a network device
10778 *	@dev: device to register
10779 *
10780 *	Take a completed network device structure and add it to the kernel
10781 *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
10782 *	chain. 0 is returned on success. A negative errno code is returned
10783 *	on a failure to set up the device, or if the name is a duplicate.
10784 *
10785 *	This is a wrapper around register_netdevice that takes the rtnl semaphore
10786 *	and expands the device name if you passed a format string to
10787 *	alloc_netdev.
10788 */
10789int register_netdev(struct net_device *dev)
10790{
10791	int err;
10792
10793	if (rtnl_lock_killable())
10794		return -EINTR;
10795	err = register_netdevice(dev);
10796	rtnl_unlock();
10797	return err;
10798}
10799EXPORT_SYMBOL(register_netdev);
10800
10801int netdev_refcnt_read(const struct net_device *dev)
10802{
10803#ifdef CONFIG_PCPU_DEV_REFCNT
10804	int i, refcnt = 0;
10805
10806	for_each_possible_cpu(i)
10807		refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
10808	return refcnt;
10809#else
10810	return refcount_read(&dev->dev_refcnt);
10811#endif
10812}
10813EXPORT_SYMBOL(netdev_refcnt_read);
10814
10815int netdev_unregister_timeout_secs __read_mostly = 10;
10816
10817#define WAIT_REFS_MIN_MSECS 1
10818#define WAIT_REFS_MAX_MSECS 250
10819/**
10820 * netdev_wait_allrefs_any - wait until all references are gone.
10821 * @list: list of net_devices to wait on
10822 *
10823 * This is called when unregistering network devices.
10824 *
10825 * Any protocol or device that holds a reference should register
10826 * for netdevice notification, and cleanup and put back the
10827 * reference if they receive an UNREGISTER event.
10828 * We can get stuck here if buggy protocols don't correctly
10829 * call dev_put.
10830 */
10831static struct net_device *netdev_wait_allrefs_any(struct list_head *list)
10832{
10833	unsigned long rebroadcast_time, warning_time;
10834	struct net_device *dev;
10835	int wait = 0;
10836
10837	rebroadcast_time = warning_time = jiffies;
10838
10839	list_for_each_entry(dev, list, todo_list)
10840		if (netdev_refcnt_read(dev) == 1)
10841			return dev;
10842
10843	while (true) {
10844		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
10845			rtnl_lock();
10846
10847			/* Rebroadcast unregister notification */
10848			list_for_each_entry(dev, list, todo_list)
10849				call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
10850
10851			__rtnl_unlock();
10852			rcu_barrier();
10853			rtnl_lock();
10854
10855			list_for_each_entry(dev, list, todo_list)
10856				if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
10857					     &dev->state)) {
10858					/* We must not have linkwatch events
10859					 * pending on unregister. If this
10860					 * happens, we simply run the queue
10861					 * unscheduled, resulting in a noop
10862					 * for this device.
10863					 */
10864					linkwatch_run_queue();
10865					break;
10866				}
10867
10868			__rtnl_unlock();
10869
10870			rebroadcast_time = jiffies;
10871		}
10872
10873		rcu_barrier();
10874
10875		if (!wait) {
10876			wait = WAIT_REFS_MIN_MSECS;
10877		} else {
10878			msleep(wait);
10879			wait = min(wait << 1, WAIT_REFS_MAX_MSECS);
10880		}
10881
10882		list_for_each_entry(dev, list, todo_list)
10883			if (netdev_refcnt_read(dev) == 1)
10884				return dev;
10885
10886		if (time_after(jiffies, warning_time +
10887			       READ_ONCE(netdev_unregister_timeout_secs) * HZ)) {
10888			list_for_each_entry(dev, list, todo_list) {
10889				pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
10890					 dev->name, netdev_refcnt_read(dev));
10891				ref_tracker_dir_print(&dev->refcnt_tracker, 10);
10892			}
10893
 
 
 
 
 
10894			warning_time = jiffies;
10895		}
10896	}
10897}
10898
10899/* The sequence is:
10900 *
10901 *	rtnl_lock();
10902 *	...
10903 *	register_netdevice(x1);
10904 *	register_netdevice(x2);
10905 *	...
10906 *	unregister_netdevice(y1);
10907 *	unregister_netdevice(y2);
10908 *      ...
10909 *	rtnl_unlock();
10910 *	free_netdev(y1);
10911 *	free_netdev(y2);
10912 *
10913 * We are invoked by rtnl_unlock().
10914 * This allows us to deal with problems:
10915 * 1) We can delete sysfs objects which invoke hotplug
10916 *    without deadlocking with linkwatch via keventd.
10917 * 2) Since we run with the RTNL semaphore not held, we can sleep
10918 *    safely in order to wait for the netdev refcnt to drop to zero.
10919 *
10920 * We must not return until all unregister events added during
10921 * the interval the lock was held have been completed.
10922 */
10923void netdev_run_todo(void)
10924{
10925	struct net_device *dev, *tmp;
10926	struct list_head list;
10927	int cnt;
10928#ifdef CONFIG_LOCKDEP
10929	struct list_head unlink_list;
10930
10931	list_replace_init(&net_unlink_list, &unlink_list);
10932
10933	while (!list_empty(&unlink_list)) {
10934		struct net_device *dev = list_first_entry(&unlink_list,
10935							  struct net_device,
10936							  unlink_list);
10937		list_del_init(&dev->unlink_list);
10938		dev->nested_level = dev->lower_level - 1;
10939	}
10940#endif
10941
10942	/* Snapshot list, allow later requests */
10943	list_replace_init(&net_todo_list, &list);
10944
10945	__rtnl_unlock();
10946
10947	/* Wait for rcu callbacks to finish before next phase */
10948	if (!list_empty(&list))
10949		rcu_barrier();
 
10950
10951	list_for_each_entry_safe(dev, tmp, &list, todo_list) {
10952		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
10953			netdev_WARN(dev, "run_todo but not unregistering\n");
10954			list_del(&dev->todo_list);
 
10955			continue;
10956		}
10957
10958		WRITE_ONCE(dev->reg_state, NETREG_UNREGISTERED);
10959		linkwatch_sync_dev(dev);
10960	}
10961
10962	cnt = 0;
10963	while (!list_empty(&list)) {
10964		dev = netdev_wait_allrefs_any(&list);
10965		list_del(&dev->todo_list);
10966
10967		/* paranoia */
10968		BUG_ON(netdev_refcnt_read(dev) != 1);
10969		BUG_ON(!list_empty(&dev->ptype_all));
10970		BUG_ON(!list_empty(&dev->ptype_specific));
10971		WARN_ON(rcu_access_pointer(dev->ip_ptr));
10972		WARN_ON(rcu_access_pointer(dev->ip6_ptr));
10973
10974		netdev_do_free_pcpu_stats(dev);
10975		if (dev->priv_destructor)
10976			dev->priv_destructor(dev);
10977		if (dev->needs_free_netdev)
10978			free_netdev(dev);
10979
10980		cnt++;
 
10981
10982		/* Free network device */
10983		kobject_put(&dev->dev.kobj);
10984	}
10985	if (cnt && atomic_sub_and_test(cnt, &dev_unreg_count))
10986		wake_up(&netdev_unregistering_wq);
10987}
10988
10989/* Collate per-cpu network dstats statistics
10990 *
10991 * Read per-cpu network statistics from dev->dstats and populate the related
10992 * fields in @s.
10993 */
10994static void dev_fetch_dstats(struct rtnl_link_stats64 *s,
10995			     const struct pcpu_dstats __percpu *dstats)
10996{
10997	int cpu;
10998
10999	for_each_possible_cpu(cpu) {
11000		u64 rx_packets, rx_bytes, rx_drops;
11001		u64 tx_packets, tx_bytes, tx_drops;
11002		const struct pcpu_dstats *stats;
11003		unsigned int start;
11004
11005		stats = per_cpu_ptr(dstats, cpu);
11006		do {
11007			start = u64_stats_fetch_begin(&stats->syncp);
11008			rx_packets = u64_stats_read(&stats->rx_packets);
11009			rx_bytes   = u64_stats_read(&stats->rx_bytes);
11010			rx_drops   = u64_stats_read(&stats->rx_drops);
11011			tx_packets = u64_stats_read(&stats->tx_packets);
11012			tx_bytes   = u64_stats_read(&stats->tx_bytes);
11013			tx_drops   = u64_stats_read(&stats->tx_drops);
11014		} while (u64_stats_fetch_retry(&stats->syncp, start));
11015
11016		s->rx_packets += rx_packets;
11017		s->rx_bytes   += rx_bytes;
11018		s->rx_dropped += rx_drops;
11019		s->tx_packets += tx_packets;
11020		s->tx_bytes   += tx_bytes;
11021		s->tx_dropped += tx_drops;
11022	}
11023}
11024
11025/* ndo_get_stats64 implementation for dtstats-based accounting.
11026 *
11027 * Populate @s from dev->stats and dev->dstats. This is used internally by the
11028 * core for NETDEV_PCPU_STAT_DSTAT-type stats collection.
11029 */
11030static void dev_get_dstats64(const struct net_device *dev,
11031			     struct rtnl_link_stats64 *s)
11032{
11033	netdev_stats_to_stats64(s, &dev->stats);
11034	dev_fetch_dstats(s, dev->dstats);
11035}
11036
11037/* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has
11038 * all the same fields in the same order as net_device_stats, with only
11039 * the type differing, but rtnl_link_stats64 may have additional fields
11040 * at the end for newer counters.
11041 */
11042void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
11043			     const struct net_device_stats *netdev_stats)
11044{
11045	size_t i, n = sizeof(*netdev_stats) / sizeof(atomic_long_t);
11046	const atomic_long_t *src = (atomic_long_t *)netdev_stats;
11047	u64 *dst = (u64 *)stats64;
11048
11049	BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64));
 
11050	for (i = 0; i < n; i++)
11051		dst[i] = (unsigned long)atomic_long_read(&src[i]);
11052	/* zero out counters that only exist in rtnl_link_stats64 */
11053	memset((char *)stats64 + n * sizeof(u64), 0,
11054	       sizeof(*stats64) - n * sizeof(u64));
11055}
11056EXPORT_SYMBOL(netdev_stats_to_stats64);
11057
11058static __cold struct net_device_core_stats __percpu *netdev_core_stats_alloc(
11059		struct net_device *dev)
11060{
11061	struct net_device_core_stats __percpu *p;
11062
11063	p = alloc_percpu_gfp(struct net_device_core_stats,
11064			     GFP_ATOMIC | __GFP_NOWARN);
11065
11066	if (p && cmpxchg(&dev->core_stats, NULL, p))
11067		free_percpu(p);
11068
11069	/* This READ_ONCE() pairs with the cmpxchg() above */
11070	return READ_ONCE(dev->core_stats);
11071}
11072
11073noinline void netdev_core_stats_inc(struct net_device *dev, u32 offset)
11074{
11075	/* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */
11076	struct net_device_core_stats __percpu *p = READ_ONCE(dev->core_stats);
11077	unsigned long __percpu *field;
11078
11079	if (unlikely(!p)) {
11080		p = netdev_core_stats_alloc(dev);
11081		if (!p)
11082			return;
11083	}
11084
11085	field = (unsigned long __percpu *)((void __percpu *)p + offset);
11086	this_cpu_inc(*field);
11087}
11088EXPORT_SYMBOL_GPL(netdev_core_stats_inc);
11089
11090/**
11091 *	dev_get_stats	- get network device statistics
11092 *	@dev: device to get statistics from
11093 *	@storage: place to store stats
11094 *
11095 *	Get network statistics from device. Return @storage.
11096 *	The device driver may provide its own method by setting
11097 *	dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
11098 *	otherwise the internal statistics structure is used.
11099 */
11100struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
11101					struct rtnl_link_stats64 *storage)
11102{
11103	const struct net_device_ops *ops = dev->netdev_ops;
11104	const struct net_device_core_stats __percpu *p;
11105
11106	if (ops->ndo_get_stats64) {
11107		memset(storage, 0, sizeof(*storage));
11108		ops->ndo_get_stats64(dev, storage);
11109	} else if (ops->ndo_get_stats) {
11110		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
11111	} else if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_TSTATS) {
11112		dev_get_tstats64(dev, storage);
11113	} else if (dev->pcpu_stat_type == NETDEV_PCPU_STAT_DSTATS) {
11114		dev_get_dstats64(dev, storage);
11115	} else {
11116		netdev_stats_to_stats64(storage, &dev->stats);
11117	}
11118
11119	/* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */
11120	p = READ_ONCE(dev->core_stats);
11121	if (p) {
11122		const struct net_device_core_stats *core_stats;
11123		int i;
11124
11125		for_each_possible_cpu(i) {
11126			core_stats = per_cpu_ptr(p, i);
11127			storage->rx_dropped += READ_ONCE(core_stats->rx_dropped);
11128			storage->tx_dropped += READ_ONCE(core_stats->tx_dropped);
11129			storage->rx_nohandler += READ_ONCE(core_stats->rx_nohandler);
11130			storage->rx_otherhost_dropped += READ_ONCE(core_stats->rx_otherhost_dropped);
11131		}
11132	}
11133	return storage;
11134}
11135EXPORT_SYMBOL(dev_get_stats);
11136
11137/**
11138 *	dev_fetch_sw_netstats - get per-cpu network device statistics
11139 *	@s: place to store stats
11140 *	@netstats: per-cpu network stats to read from
11141 *
11142 *	Read per-cpu network statistics and populate the related fields in @s.
11143 */
11144void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s,
11145			   const struct pcpu_sw_netstats __percpu *netstats)
11146{
11147	int cpu;
11148
11149	for_each_possible_cpu(cpu) {
11150		u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
11151		const struct pcpu_sw_netstats *stats;
11152		unsigned int start;
11153
11154		stats = per_cpu_ptr(netstats, cpu);
11155		do {
11156			start = u64_stats_fetch_begin(&stats->syncp);
11157			rx_packets = u64_stats_read(&stats->rx_packets);
11158			rx_bytes   = u64_stats_read(&stats->rx_bytes);
11159			tx_packets = u64_stats_read(&stats->tx_packets);
11160			tx_bytes   = u64_stats_read(&stats->tx_bytes);
11161		} while (u64_stats_fetch_retry(&stats->syncp, start));
11162
11163		s->rx_packets += rx_packets;
11164		s->rx_bytes   += rx_bytes;
11165		s->tx_packets += tx_packets;
11166		s->tx_bytes   += tx_bytes;
11167	}
11168}
11169EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats);
11170
11171/**
11172 *	dev_get_tstats64 - ndo_get_stats64 implementation
11173 *	@dev: device to get statistics from
11174 *	@s: place to store stats
11175 *
11176 *	Populate @s from dev->stats and dev->tstats. Can be used as
11177 *	ndo_get_stats64() callback.
11178 */
11179void dev_get_tstats64(struct net_device *dev, struct rtnl_link_stats64 *s)
11180{
11181	netdev_stats_to_stats64(s, &dev->stats);
11182	dev_fetch_sw_netstats(s, dev->tstats);
11183}
11184EXPORT_SYMBOL_GPL(dev_get_tstats64);
11185
11186struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
11187{
11188	struct netdev_queue *queue = dev_ingress_queue(dev);
11189
11190#ifdef CONFIG_NET_CLS_ACT
11191	if (queue)
11192		return queue;
11193	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
11194	if (!queue)
11195		return NULL;
11196	netdev_init_one_queue(dev, queue, NULL);
11197	RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
11198	RCU_INIT_POINTER(queue->qdisc_sleeping, &noop_qdisc);
11199	rcu_assign_pointer(dev->ingress_queue, queue);
11200#endif
11201	return queue;
11202}
11203
11204static const struct ethtool_ops default_ethtool_ops;
11205
11206void netdev_set_default_ethtool_ops(struct net_device *dev,
11207				    const struct ethtool_ops *ops)
11208{
11209	if (dev->ethtool_ops == &default_ethtool_ops)
11210		dev->ethtool_ops = ops;
11211}
11212EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
11213
11214/**
11215 * netdev_sw_irq_coalesce_default_on() - enable SW IRQ coalescing by default
11216 * @dev: netdev to enable the IRQ coalescing on
11217 *
11218 * Sets a conservative default for SW IRQ coalescing. Users can use
11219 * sysfs attributes to override the default values.
11220 */
11221void netdev_sw_irq_coalesce_default_on(struct net_device *dev)
11222{
11223	WARN_ON(dev->reg_state == NETREG_REGISTERED);
11224
11225	if (!IS_ENABLED(CONFIG_PREEMPT_RT)) {
11226		netdev_set_gro_flush_timeout(dev, 20000);
11227		netdev_set_defer_hard_irqs(dev, 1);
11228	}
11229}
11230EXPORT_SYMBOL_GPL(netdev_sw_irq_coalesce_default_on);
11231
11232/**
11233 * alloc_netdev_mqs - allocate network device
11234 * @sizeof_priv: size of private data to allocate space for
11235 * @name: device name format string
11236 * @name_assign_type: origin of device name
11237 * @setup: callback to initialize device
11238 * @txqs: the number of TX subqueues to allocate
11239 * @rxqs: the number of RX subqueues to allocate
11240 *
11241 * Allocates a struct net_device with private data area for driver use
11242 * and performs basic initialization.  Also allocates subqueue structs
11243 * for each queue on the device.
11244 */
11245struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
11246		unsigned char name_assign_type,
11247		void (*setup)(struct net_device *),
11248		unsigned int txqs, unsigned int rxqs)
11249{
11250	struct net_device *dev;
11251	size_t napi_config_sz;
11252	unsigned int maxqs;
11253
11254	BUG_ON(strlen(name) >= sizeof(dev->name));
11255
11256	if (txqs < 1) {
11257		pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
 
11258		return NULL;
11259	}
11260
 
11261	if (rxqs < 1) {
11262		pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
 
11263		return NULL;
11264	}
 
11265
11266	maxqs = max(txqs, rxqs);
11267
11268	dev = kvzalloc(struct_size(dev, priv, sizeof_priv),
11269		       GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);
11270	if (!dev)
 
 
 
 
 
 
 
11271		return NULL;
 
11272
11273	dev->priv_len = sizeof_priv;
 
11274
11275	ref_tracker_dir_init(&dev->refcnt_tracker, 128, name);
11276#ifdef CONFIG_PCPU_DEV_REFCNT
11277	dev->pcpu_refcnt = alloc_percpu(int);
11278	if (!dev->pcpu_refcnt)
11279		goto free_dev;
11280	__dev_hold(dev);
11281#else
11282	refcount_set(&dev->dev_refcnt, 1);
11283#endif
11284
11285	if (dev_addr_init(dev))
11286		goto free_pcpu;
11287
11288	dev_mc_init(dev);
11289	dev_uc_init(dev);
11290
11291	dev_net_set(dev, &init_net);
11292
11293	dev->gso_max_size = GSO_LEGACY_MAX_SIZE;
11294	dev->xdp_zc_max_segs = 1;
11295	dev->gso_max_segs = GSO_MAX_SEGS;
11296	dev->gro_max_size = GRO_LEGACY_MAX_SIZE;
11297	dev->gso_ipv4_max_size = GSO_LEGACY_MAX_SIZE;
11298	dev->gro_ipv4_max_size = GRO_LEGACY_MAX_SIZE;
11299	dev->tso_max_size = TSO_LEGACY_MAX_SIZE;
11300	dev->tso_max_segs = TSO_MAX_SEGS;
11301	dev->upper_level = 1;
11302	dev->lower_level = 1;
11303#ifdef CONFIG_LOCKDEP
11304	dev->nested_level = 0;
11305	INIT_LIST_HEAD(&dev->unlink_list);
11306#endif
11307
11308	INIT_LIST_HEAD(&dev->napi_list);
11309	INIT_LIST_HEAD(&dev->unreg_list);
11310	INIT_LIST_HEAD(&dev->close_list);
11311	INIT_LIST_HEAD(&dev->link_watch_list);
11312	INIT_LIST_HEAD(&dev->adj_list.upper);
11313	INIT_LIST_HEAD(&dev->adj_list.lower);
11314	INIT_LIST_HEAD(&dev->ptype_all);
11315	INIT_LIST_HEAD(&dev->ptype_specific);
11316	INIT_LIST_HEAD(&dev->net_notifier_list);
11317#ifdef CONFIG_NET_SCHED
11318	hash_init(dev->qdisc_hash);
11319#endif
11320
11321	mutex_init(&dev->lock);
11322
11323	dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
11324	setup(dev);
11325
11326	if (!dev->tx_queue_len) {
11327		dev->priv_flags |= IFF_NO_QUEUE;
11328		dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
11329	}
11330
11331	dev->num_tx_queues = txqs;
11332	dev->real_num_tx_queues = txqs;
11333	if (netif_alloc_netdev_queues(dev))
11334		goto free_all;
11335
 
11336	dev->num_rx_queues = rxqs;
11337	dev->real_num_rx_queues = rxqs;
11338	if (netif_alloc_rx_queues(dev))
11339		goto free_all;
11340	dev->ethtool = kzalloc(sizeof(*dev->ethtool), GFP_KERNEL_ACCOUNT);
11341	if (!dev->ethtool)
11342		goto free_all;
11343
11344	napi_config_sz = array_size(maxqs, sizeof(*dev->napi_config));
11345	dev->napi_config = kvzalloc(napi_config_sz, GFP_KERNEL_ACCOUNT);
11346	if (!dev->napi_config)
11347		goto free_all;
11348
11349	strscpy(dev->name, name);
11350	dev->name_assign_type = name_assign_type;
11351	dev->group = INIT_NETDEV_GROUP;
11352	if (!dev->ethtool_ops)
11353		dev->ethtool_ops = &default_ethtool_ops;
11354
11355	nf_hook_netdev_init(dev);
11356
11357	return dev;
11358
11359free_all:
11360	free_netdev(dev);
11361	return NULL;
11362
11363free_pcpu:
11364#ifdef CONFIG_PCPU_DEV_REFCNT
11365	free_percpu(dev->pcpu_refcnt);
11366free_dev:
 
 
11367#endif
11368	kvfree(dev);
 
 
11369	return NULL;
11370}
11371EXPORT_SYMBOL(alloc_netdev_mqs);
11372
11373/**
11374 * free_netdev - free network device
11375 * @dev: device
11376 *
11377 * This function does the last stage of destroying an allocated device
11378 * interface. The reference to the device object is released. If this
11379 * is the last reference then it will be freed.Must be called in process
11380 * context.
11381 */
11382void free_netdev(struct net_device *dev)
11383{
11384	struct napi_struct *p, *n;
11385
11386	might_sleep();
11387
11388	/* When called immediately after register_netdevice() failed the unwind
11389	 * handling may still be dismantling the device. Handle that case by
11390	 * deferring the free.
11391	 */
11392	if (dev->reg_state == NETREG_UNREGISTERING) {
11393		ASSERT_RTNL();
11394		dev->needs_free_netdev = true;
11395		return;
11396	}
11397
11398	mutex_destroy(&dev->lock);
11399
11400	kfree(dev->ethtool);
11401	netif_free_tx_queues(dev);
11402	netif_free_rx_queues(dev);
 
11403
11404	kfree(rcu_dereference_protected(dev->ingress_queue, 1));
11405
11406	/* Flush device addresses */
11407	dev_addr_flush(dev);
11408
11409	list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
11410		netif_napi_del(p);
11411
11412	kvfree(dev->napi_config);
11413
11414	ref_tracker_dir_exit(&dev->refcnt_tracker);
11415#ifdef CONFIG_PCPU_DEV_REFCNT
11416	free_percpu(dev->pcpu_refcnt);
11417	dev->pcpu_refcnt = NULL;
11418#endif
11419	free_percpu(dev->core_stats);
11420	dev->core_stats = NULL;
11421	free_percpu(dev->xdp_bulkq);
11422	dev->xdp_bulkq = NULL;
11423
11424	netdev_free_phy_link_topology(dev);
11425
11426	/*  Compatibility with error handling in drivers */
11427	if (dev->reg_state == NETREG_UNINITIALIZED ||
11428	    dev->reg_state == NETREG_DUMMY) {
11429		kvfree(dev);
11430		return;
11431	}
11432
11433	BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
11434	WRITE_ONCE(dev->reg_state, NETREG_RELEASED);
11435
11436	/* will free via device release */
11437	put_device(&dev->dev);
11438}
11439EXPORT_SYMBOL(free_netdev);
11440
11441/**
11442 * alloc_netdev_dummy - Allocate and initialize a dummy net device.
11443 * @sizeof_priv: size of private data to allocate space for
11444 *
11445 * Return: the allocated net_device on success, NULL otherwise
11446 */
11447struct net_device *alloc_netdev_dummy(int sizeof_priv)
11448{
11449	return alloc_netdev(sizeof_priv, "dummy#", NET_NAME_UNKNOWN,
11450			    init_dummy_netdev_core);
11451}
11452EXPORT_SYMBOL_GPL(alloc_netdev_dummy);
11453
11454/**
11455 *	synchronize_net -  Synchronize with packet receive processing
11456 *
11457 *	Wait for packets currently being received to be done.
11458 *	Does not block later packets from starting.
11459 */
11460void synchronize_net(void)
11461{
11462	might_sleep();
11463	if (rtnl_is_locked())
11464		synchronize_rcu_expedited();
11465	else
11466		synchronize_rcu();
11467}
11468EXPORT_SYMBOL(synchronize_net);
11469
11470static void netdev_rss_contexts_free(struct net_device *dev)
11471{
11472	struct ethtool_rxfh_context *ctx;
11473	unsigned long context;
11474
11475	mutex_lock(&dev->ethtool->rss_lock);
11476	xa_for_each(&dev->ethtool->rss_ctx, context, ctx) {
11477		struct ethtool_rxfh_param rxfh;
11478
11479		rxfh.indir = ethtool_rxfh_context_indir(ctx);
11480		rxfh.key = ethtool_rxfh_context_key(ctx);
11481		rxfh.hfunc = ctx->hfunc;
11482		rxfh.input_xfrm = ctx->input_xfrm;
11483		rxfh.rss_context = context;
11484		rxfh.rss_delete = true;
11485
11486		xa_erase(&dev->ethtool->rss_ctx, context);
11487		if (dev->ethtool_ops->create_rxfh_context)
11488			dev->ethtool_ops->remove_rxfh_context(dev, ctx,
11489							      context, NULL);
11490		else
11491			dev->ethtool_ops->set_rxfh(dev, &rxfh, NULL);
11492		kfree(ctx);
11493	}
11494	xa_destroy(&dev->ethtool->rss_ctx);
11495	mutex_unlock(&dev->ethtool->rss_lock);
11496}
11497
11498/**
11499 *	unregister_netdevice_queue - remove device from the kernel
11500 *	@dev: device
11501 *	@head: list
11502 *
11503 *	This function shuts down a device interface and removes it
11504 *	from the kernel tables.
11505 *	If head not NULL, device is queued to be unregistered later.
11506 *
11507 *	Callers must hold the rtnl semaphore.  You may want
11508 *	unregister_netdev() instead of this.
11509 */
11510
11511void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
11512{
11513	ASSERT_RTNL();
11514
11515	if (head) {
11516		list_move_tail(&dev->unreg_list, head);
11517	} else {
11518		LIST_HEAD(single);
11519
11520		list_add(&dev->unreg_list, &single);
11521		unregister_netdevice_many(&single);
11522	}
11523}
11524EXPORT_SYMBOL(unregister_netdevice_queue);
11525
11526void unregister_netdevice_many_notify(struct list_head *head,
11527				      u32 portid, const struct nlmsghdr *nlh)
11528{
11529	struct net_device *dev, *tmp;
11530	LIST_HEAD(close_head);
11531	int cnt = 0;
11532
11533	BUG_ON(dev_boot_phase);
11534	ASSERT_RTNL();
11535
11536	if (list_empty(head))
11537		return;
11538
11539	list_for_each_entry_safe(dev, tmp, head, unreg_list) {
11540		/* Some devices call without registering
11541		 * for initialization unwind. Remove those
11542		 * devices and proceed with the remaining.
11543		 */
11544		if (dev->reg_state == NETREG_UNINITIALIZED) {
11545			pr_debug("unregister_netdevice: device %s/%p never was registered\n",
11546				 dev->name, dev);
11547
11548			WARN_ON(1);
11549			list_del(&dev->unreg_list);
11550			continue;
11551		}
11552		dev->dismantle = true;
11553		BUG_ON(dev->reg_state != NETREG_REGISTERED);
11554	}
11555
11556	/* If device is running, close it first. */
11557	list_for_each_entry(dev, head, unreg_list)
11558		list_add_tail(&dev->close_list, &close_head);
11559	dev_close_many(&close_head, true);
11560
11561	list_for_each_entry(dev, head, unreg_list) {
11562		/* And unlink it from device chain. */
11563		unlist_netdevice(dev);
11564		WRITE_ONCE(dev->reg_state, NETREG_UNREGISTERING);
11565	}
11566	flush_all_backlogs();
11567
11568	synchronize_net();
11569
11570	list_for_each_entry(dev, head, unreg_list) {
11571		struct sk_buff *skb = NULL;
11572
11573		/* Shutdown queueing discipline. */
11574		dev_shutdown(dev);
11575		dev_tcx_uninstall(dev);
11576		dev_xdp_uninstall(dev);
11577		bpf_dev_bound_netdev_unregister(dev);
11578		dev_dmabuf_uninstall(dev);
11579
11580		netdev_offload_xstats_disable_all(dev);
11581
11582		/* Notify protocols, that we are about to destroy
11583		 * this device. They should clean all the things.
11584		 */
11585		call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
11586
11587		if (!dev->rtnl_link_ops ||
11588		    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
11589			skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0,
11590						     GFP_KERNEL, NULL, 0,
11591						     portid, nlh);
11592
11593		/*
11594		 *	Flush the unicast and multicast chains
11595		 */
11596		dev_uc_flush(dev);
11597		dev_mc_flush(dev);
11598
11599		netdev_name_node_alt_flush(dev);
11600		netdev_name_node_free(dev->name_node);
11601
11602		netdev_rss_contexts_free(dev);
11603
11604		call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev);
11605
11606		if (dev->netdev_ops->ndo_uninit)
11607			dev->netdev_ops->ndo_uninit(dev);
11608
11609		mutex_destroy(&dev->ethtool->rss_lock);
11610
11611		net_shaper_flush_netdev(dev);
11612
11613		if (skb)
11614			rtmsg_ifinfo_send(skb, dev, GFP_KERNEL, portid, nlh);
11615
11616		/* Notifier chain MUST detach us all upper devices. */
11617		WARN_ON(netdev_has_any_upper_dev(dev));
11618		WARN_ON(netdev_has_any_lower_dev(dev));
11619
11620		/* Remove entries from kobject tree */
11621		netdev_unregister_kobject(dev);
11622#ifdef CONFIG_XPS
11623		/* Remove XPS queueing entries */
11624		netif_reset_xps_queues_gt(dev, 0);
11625#endif
11626	}
11627
11628	synchronize_net();
11629
11630	list_for_each_entry(dev, head, unreg_list) {
11631		netdev_put(dev, &dev->dev_registered_tracker);
11632		net_set_todo(dev);
11633		cnt++;
11634	}
11635	atomic_add(cnt, &dev_unreg_count);
11636
11637	list_del(head);
11638}
 
11639
11640/**
11641 *	unregister_netdevice_many - unregister many devices
11642 *	@head: list of devices
11643 *
11644 *  Note: As most callers use a stack allocated list_head,
11645 *  we force a list_del() to make sure stack won't be corrupted later.
11646 */
11647void unregister_netdevice_many(struct list_head *head)
11648{
11649	unregister_netdevice_many_notify(head, 0, NULL);
 
 
 
 
 
 
11650}
11651EXPORT_SYMBOL(unregister_netdevice_many);
11652
11653/**
11654 *	unregister_netdev - remove device from the kernel
11655 *	@dev: device
11656 *
11657 *	This function shuts down a device interface and removes it
11658 *	from the kernel tables.
11659 *
11660 *	This is just a wrapper for unregister_netdevice that takes
11661 *	the rtnl semaphore.  In general you want to use this and not
11662 *	unregister_netdevice.
11663 */
11664void unregister_netdev(struct net_device *dev)
11665{
11666	rtnl_lock();
11667	unregister_netdevice(dev);
11668	rtnl_unlock();
11669}
11670EXPORT_SYMBOL(unregister_netdev);
11671
11672/**
11673 *	__dev_change_net_namespace - move device to different nethost namespace
11674 *	@dev: device
11675 *	@net: network namespace
11676 *	@pat: If not NULL name pattern to try if the current device name
11677 *	      is already taken in the destination network namespace.
11678 *	@new_ifindex: If not zero, specifies device index in the target
11679 *	              namespace.
11680 *
11681 *	This function shuts down a device interface and moves it
11682 *	to a new network namespace. On success 0 is returned, on
11683 *	a failure a netagive errno code is returned.
11684 *
11685 *	Callers must hold the rtnl semaphore.
11686 */
11687
11688int __dev_change_net_namespace(struct net_device *dev, struct net *net,
11689			       const char *pat, int new_ifindex)
11690{
11691	struct netdev_name_node *name_node;
11692	struct net *net_old = dev_net(dev);
11693	char new_name[IFNAMSIZ] = {};
11694	int err, new_nsid;
11695
11696	ASSERT_RTNL();
11697
11698	/* Don't allow namespace local devices to be moved. */
11699	err = -EINVAL;
11700	if (dev->netns_local)
11701		goto out;
11702
11703	/* Ensure the device has been registered */
 
11704	if (dev->reg_state != NETREG_REGISTERED)
11705		goto out;
11706
11707	/* Get out if there is nothing todo */
11708	err = 0;
11709	if (net_eq(net_old, net))
11710		goto out;
11711
11712	/* Pick the destination device name, and ensure
11713	 * we can use it in the destination network namespace.
11714	 */
11715	err = -EEXIST;
11716	if (netdev_name_in_use(net, dev->name)) {
11717		/* We get here if we can't use the current device name */
11718		if (!pat)
11719			goto out;
11720		err = dev_prep_valid_name(net, dev, pat, new_name, EEXIST);
11721		if (err < 0)
11722			goto out;
11723	}
11724	/* Check that none of the altnames conflicts. */
11725	err = -EEXIST;
11726	netdev_for_each_altname(dev, name_node)
11727		if (netdev_name_in_use(net, name_node->name))
11728			goto out;
11729
11730	/* Check that new_ifindex isn't used yet. */
11731	if (new_ifindex) {
11732		err = dev_index_reserve(net, new_ifindex);
11733		if (err < 0)
11734			goto out;
11735	} else {
11736		/* If there is an ifindex conflict assign a new one */
11737		err = dev_index_reserve(net, dev->ifindex);
11738		if (err == -EBUSY)
11739			err = dev_index_reserve(net, 0);
11740		if (err < 0)
11741			goto out;
11742		new_ifindex = err;
11743	}
11744
11745	/*
11746	 * And now a mini version of register_netdevice unregister_netdevice.
11747	 */
11748
11749	/* If device is running close it first. */
11750	dev_close(dev);
11751
11752	/* And unlink it from device chain */
 
11753	unlist_netdevice(dev);
11754
11755	synchronize_net();
11756
11757	/* Shutdown queueing discipline. */
11758	dev_shutdown(dev);
11759
11760	/* Notify protocols, that we are about to destroy
11761	 * this device. They should clean all the things.
11762	 *
11763	 * Note that dev->reg_state stays at NETREG_REGISTERED.
11764	 * This is wanted because this way 8021q and macvlan know
11765	 * the device is just moving and can keep their slaves up.
11766	 */
11767	call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
11768	rcu_barrier();
11769
11770	new_nsid = peernet2id_alloc(dev_net(dev), net, GFP_KERNEL);
11771
11772	rtmsg_ifinfo_newnet(RTM_DELLINK, dev, ~0U, GFP_KERNEL, &new_nsid,
11773			    new_ifindex);
 
 
11774
11775	/*
11776	 *	Flush the unicast and multicast chains
11777	 */
11778	dev_uc_flush(dev);
11779	dev_mc_flush(dev);
11780
11781	/* Send a netdev-removed uevent to the old namespace */
11782	kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
11783	netdev_adjacent_del_links(dev);
11784
11785	/* Move per-net netdevice notifiers that are following the netdevice */
11786	move_netdevice_notifiers_dev_net(dev, net);
11787
11788	/* Actually switch the network namespace */
11789	dev_net_set(dev, net);
11790	dev->ifindex = new_ifindex;
11791
11792	if (new_name[0]) {
11793		/* Rename the netdev to prepared name */
11794		write_seqlock_bh(&netdev_rename_lock);
11795		strscpy(dev->name, new_name, IFNAMSIZ);
11796		write_sequnlock_bh(&netdev_rename_lock);
 
11797	}
11798
11799	/* Fixup kobjects */
11800	dev_set_uevent_suppress(&dev->dev, 1);
11801	err = device_rename(&dev->dev, dev->name);
11802	dev_set_uevent_suppress(&dev->dev, 0);
11803	WARN_ON(err);
11804
11805	/* Send a netdev-add uevent to the new namespace */
11806	kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
11807	netdev_adjacent_add_links(dev);
11808
11809	/* Adapt owner in case owning user namespace of target network
11810	 * namespace is different from the original one.
11811	 */
11812	err = netdev_change_owner(dev, net_old, net);
11813	WARN_ON(err);
11814
11815	/* Add the device back in the hashes */
11816	list_netdevice(dev);
11817
11818	/* Notify protocols, that a new device appeared. */
11819	call_netdevice_notifiers(NETDEV_REGISTER, dev);
11820
11821	/*
11822	 *	Prevent userspace races by waiting until the network
11823	 *	device is fully setup before sending notifications.
11824	 */
11825	rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL);
11826
11827	synchronize_net();
11828	err = 0;
11829out:
11830	return err;
11831}
11832EXPORT_SYMBOL_GPL(__dev_change_net_namespace);
11833
11834static int dev_cpu_dead(unsigned int oldcpu)
 
 
11835{
11836	struct sk_buff **list_skb;
11837	struct sk_buff *skb;
11838	unsigned int cpu;
11839	struct softnet_data *sd, *oldsd, *remsd = NULL;
 
 
 
11840
11841	local_irq_disable();
11842	cpu = smp_processor_id();
11843	sd = &per_cpu(softnet_data, cpu);
11844	oldsd = &per_cpu(softnet_data, oldcpu);
11845
11846	/* Find end of our completion_queue. */
11847	list_skb = &sd->completion_queue;
11848	while (*list_skb)
11849		list_skb = &(*list_skb)->next;
11850	/* Append completion queue from offline CPU. */
11851	*list_skb = oldsd->completion_queue;
11852	oldsd->completion_queue = NULL;
11853
11854	/* Append output queue from offline CPU. */
11855	if (oldsd->output_queue) {
11856		*sd->output_queue_tailp = oldsd->output_queue;
11857		sd->output_queue_tailp = oldsd->output_queue_tailp;
11858		oldsd->output_queue = NULL;
11859		oldsd->output_queue_tailp = &oldsd->output_queue;
11860	}
11861	/* Append NAPI poll list from offline CPU, with one exception :
11862	 * process_backlog() must be called by cpu owning percpu backlog.
11863	 * We properly handle process_queue & input_pkt_queue later.
11864	 */
11865	while (!list_empty(&oldsd->poll_list)) {
11866		struct napi_struct *napi = list_first_entry(&oldsd->poll_list,
11867							    struct napi_struct,
11868							    poll_list);
11869
11870		list_del_init(&napi->poll_list);
11871		if (napi->poll == process_backlog)
11872			napi->state &= NAPIF_STATE_THREADED;
11873		else
11874			____napi_schedule(sd, napi);
11875	}
11876
11877	raise_softirq_irqoff(NET_TX_SOFTIRQ);
11878	local_irq_enable();
11879
11880	if (!use_backlog_threads()) {
11881#ifdef CONFIG_RPS
11882		remsd = oldsd->rps_ipi_list;
11883		oldsd->rps_ipi_list = NULL;
11884#endif
11885		/* send out pending IPI's on offline CPU */
11886		net_rps_send_ipi(remsd);
11887	}
11888
11889	/* Process offline CPU's input_pkt_queue */
11890	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
11891		netif_rx(skb);
11892		rps_input_queue_head_incr(oldsd);
11893	}
11894	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
11895		netif_rx(skb);
11896		rps_input_queue_head_incr(oldsd);
11897	}
11898
11899	return 0;
11900}
11901
 
11902/**
11903 *	netdev_increment_features - increment feature set by one
11904 *	@all: current feature set
11905 *	@one: new feature set
11906 *	@mask: mask feature set
11907 *
11908 *	Computes a new feature set after adding a device with feature set
11909 *	@one to the master device with current feature set @all.  Will not
11910 *	enable anything that is off in @mask. Returns the new feature set.
11911 */
11912netdev_features_t netdev_increment_features(netdev_features_t all,
11913	netdev_features_t one, netdev_features_t mask)
11914{
11915	if (mask & NETIF_F_HW_CSUM)
11916		mask |= NETIF_F_CSUM_MASK;
11917	mask |= NETIF_F_VLAN_CHALLENGED;
11918
11919	all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask;
11920	all &= one | ~NETIF_F_ALL_FOR_ALL;
11921
 
 
 
 
11922	/* If one device supports hw checksumming, set for all. */
11923	if (all & NETIF_F_HW_CSUM)
11924		all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM);
11925
11926	return all;
11927}
11928EXPORT_SYMBOL(netdev_increment_features);
11929
11930static struct hlist_head * __net_init netdev_create_hash(void)
11931{
11932	int i;
11933	struct hlist_head *hash;
11934
11935	hash = kmalloc_array(NETDEV_HASHENTRIES, sizeof(*hash), GFP_KERNEL);
11936	if (hash != NULL)
11937		for (i = 0; i < NETDEV_HASHENTRIES; i++)
11938			INIT_HLIST_HEAD(&hash[i]);
11939
11940	return hash;
11941}
11942
11943/* Initialize per network namespace state */
11944static int __net_init netdev_init(struct net *net)
11945{
11946	BUILD_BUG_ON(GRO_HASH_BUCKETS >
11947		     8 * sizeof_field(struct napi_struct, gro_bitmask));
11948
11949	INIT_LIST_HEAD(&net->dev_base_head);
11950
11951	net->dev_name_head = netdev_create_hash();
11952	if (net->dev_name_head == NULL)
11953		goto err_name;
11954
11955	net->dev_index_head = netdev_create_hash();
11956	if (net->dev_index_head == NULL)
11957		goto err_idx;
11958
11959	xa_init_flags(&net->dev_by_index, XA_FLAGS_ALLOC1);
11960
11961	RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain);
11962
11963	return 0;
11964
11965err_idx:
11966	kfree(net->dev_name_head);
11967err_name:
11968	return -ENOMEM;
11969}
11970
11971/**
11972 *	netdev_drivername - network driver for the device
11973 *	@dev: network device
11974 *
11975 *	Determine network driver for device.
11976 */
11977const char *netdev_drivername(const struct net_device *dev)
11978{
11979	const struct device_driver *driver;
11980	const struct device *parent;
11981	const char *empty = "";
11982
11983	parent = dev->dev.parent;
11984	if (!parent)
11985		return empty;
11986
11987	driver = parent->driver;
11988	if (driver && driver->name)
11989		return driver->name;
11990	return empty;
11991}
11992
11993static void __netdev_printk(const char *level, const struct net_device *dev,
11994			    struct va_format *vaf)
11995{
11996	if (dev && dev->dev.parent) {
11997		dev_printk_emit(level[1] - '0',
11998				dev->dev.parent,
11999				"%s %s %s%s: %pV",
12000				dev_driver_string(dev->dev.parent),
12001				dev_name(dev->dev.parent),
12002				netdev_name(dev), netdev_reg_state(dev),
12003				vaf);
12004	} else if (dev) {
12005		printk("%s%s%s: %pV",
12006		       level, netdev_name(dev), netdev_reg_state(dev), vaf);
12007	} else {
12008		printk("%s(NULL net_device): %pV", level, vaf);
12009	}
12010}
12011
12012void netdev_printk(const char *level, const struct net_device *dev,
12013		   const char *format, ...)
12014{
12015	struct va_format vaf;
12016	va_list args;
 
12017
12018	va_start(args, format);
12019
12020	vaf.fmt = format;
12021	vaf.va = &args;
12022
12023	__netdev_printk(level, dev, &vaf);
12024
12025	va_end(args);
 
 
12026}
12027EXPORT_SYMBOL(netdev_printk);
12028
12029#define define_netdev_printk_level(func, level)			\
12030void func(const struct net_device *dev, const char *fmt, ...)	\
12031{								\
 
12032	struct va_format vaf;					\
12033	va_list args;						\
12034								\
12035	va_start(args, fmt);					\
12036								\
12037	vaf.fmt = fmt;						\
12038	vaf.va = &args;						\
12039								\
12040	__netdev_printk(level, dev, &vaf);			\
12041								\
12042	va_end(args);						\
 
 
12043}								\
12044EXPORT_SYMBOL(func);
12045
12046define_netdev_printk_level(netdev_emerg, KERN_EMERG);
12047define_netdev_printk_level(netdev_alert, KERN_ALERT);
12048define_netdev_printk_level(netdev_crit, KERN_CRIT);
12049define_netdev_printk_level(netdev_err, KERN_ERR);
12050define_netdev_printk_level(netdev_warn, KERN_WARNING);
12051define_netdev_printk_level(netdev_notice, KERN_NOTICE);
12052define_netdev_printk_level(netdev_info, KERN_INFO);
12053
12054static void __net_exit netdev_exit(struct net *net)
12055{
12056	kfree(net->dev_name_head);
12057	kfree(net->dev_index_head);
12058	xa_destroy(&net->dev_by_index);
12059	if (net != &init_net)
12060		WARN_ON_ONCE(!list_empty(&net->dev_base_head));
12061}
12062
12063static struct pernet_operations __net_initdata netdev_net_ops = {
12064	.init = netdev_init,
12065	.exit = netdev_exit,
12066};
12067
12068static void __net_exit default_device_exit_net(struct net *net)
12069{
12070	struct netdev_name_node *name_node, *tmp;
12071	struct net_device *dev, *aux;
12072	/*
12073	 * Push all migratable network devices back to the
12074	 * initial network namespace
12075	 */
12076	ASSERT_RTNL();
12077	for_each_netdev_safe(net, dev, aux) {
12078		int err;
12079		char fb_name[IFNAMSIZ];
12080
12081		/* Ignore unmoveable devices (i.e. loopback) */
12082		if (dev->netns_local)
12083			continue;
12084
12085		/* Leave virtual devices for the generic cleanup */
12086		if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund)
12087			continue;
12088
12089		/* Push remaining network devices to init_net */
12090		snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
12091		if (netdev_name_in_use(&init_net, fb_name))
12092			snprintf(fb_name, IFNAMSIZ, "dev%%d");
12093
12094		netdev_for_each_altname_safe(dev, name_node, tmp)
12095			if (netdev_name_in_use(&init_net, name_node->name))
12096				__netdev_name_node_alt_destroy(name_node);
12097
12098		err = dev_change_net_namespace(dev, &init_net, fb_name);
12099		if (err) {
12100			pr_emerg("%s: failed to move %s to init_net: %d\n",
12101				 __func__, dev->name, err);
12102			BUG();
12103		}
12104	}
 
12105}
12106
12107static void __net_exit default_device_exit_batch(struct list_head *net_list)
12108{
12109	/* At exit all network devices most be removed from a network
12110	 * namespace.  Do this in the reverse order of registration.
12111	 * Do this across as many network namespaces as possible to
12112	 * improve batching efficiency.
12113	 */
12114	struct net_device *dev;
12115	struct net *net;
12116	LIST_HEAD(dev_kill_list);
12117
12118	rtnl_lock();
12119	list_for_each_entry(net, net_list, exit_list) {
12120		default_device_exit_net(net);
12121		cond_resched();
12122	}
12123
12124	list_for_each_entry(net, net_list, exit_list) {
12125		for_each_netdev_reverse(net, dev) {
12126			if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
12127				dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
12128			else
12129				unregister_netdevice_queue(dev, &dev_kill_list);
12130		}
12131	}
12132	unregister_netdevice_many(&dev_kill_list);
 
12133	rtnl_unlock();
12134}
12135
12136static struct pernet_operations __net_initdata default_device_ops = {
 
12137	.exit_batch = default_device_exit_batch,
12138};
12139
12140static void __init net_dev_struct_check(void)
12141{
12142	/* TX read-mostly hotpath */
12143	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, priv_flags_fast);
12144	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, netdev_ops);
12145	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, header_ops);
12146	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, _tx);
12147	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, real_num_tx_queues);
12148	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_max_size);
12149	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_ipv4_max_size);
12150	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_max_segs);
12151	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, gso_partial_features);
12152	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, num_tc);
12153	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, mtu);
12154	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, needed_headroom);
12155	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, tc_to_txq);
12156#ifdef CONFIG_XPS
12157	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, xps_maps);
12158#endif
12159#ifdef CONFIG_NETFILTER_EGRESS
12160	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, nf_hooks_egress);
12161#endif
12162#ifdef CONFIG_NET_XGRESS
12163	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_tx, tcx_egress);
12164#endif
12165	CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_tx, 160);
12166
12167	/* TXRX read-mostly hotpath */
12168	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, lstats);
12169	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, state);
12170	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, flags);
12171	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, hard_header_len);
12172	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, features);
12173	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_txrx, ip6_ptr);
12174	CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_txrx, 46);
12175
12176	/* RX read-mostly hotpath */
12177	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, ptype_specific);
12178	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, ifindex);
12179	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, real_num_rx_queues);
12180	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, _rx);
12181	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_max_size);
12182	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, gro_ipv4_max_size);
12183	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, rx_handler);
12184	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, rx_handler_data);
12185	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, nd_net);
12186#ifdef CONFIG_NETPOLL
12187	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, npinfo);
12188#endif
12189#ifdef CONFIG_NET_XGRESS
12190	CACHELINE_ASSERT_GROUP_MEMBER(struct net_device, net_device_read_rx, tcx_ingress);
12191#endif
12192	CACHELINE_ASSERT_GROUP_SIZE(struct net_device, net_device_read_rx, 92);
12193}
12194
12195/*
12196 *	Initialize the DEV module. At boot time this walks the device list and
12197 *	unhooks any devices that fail to initialise (normally hardware not
12198 *	present) and leaves us with a valid list of present and active devices.
12199 *
12200 */
12201
12202/* We allocate 256 pages for each CPU if PAGE_SHIFT is 12 */
12203#define SYSTEM_PERCPU_PAGE_POOL_SIZE	((1 << 20) / PAGE_SIZE)
12204
12205static int net_page_pool_create(int cpuid)
12206{
12207#if IS_ENABLED(CONFIG_PAGE_POOL)
12208	struct page_pool_params page_pool_params = {
12209		.pool_size = SYSTEM_PERCPU_PAGE_POOL_SIZE,
12210		.flags = PP_FLAG_SYSTEM_POOL,
12211		.nid = cpu_to_mem(cpuid),
12212	};
12213	struct page_pool *pp_ptr;
12214
12215	pp_ptr = page_pool_create_percpu(&page_pool_params, cpuid);
12216	if (IS_ERR(pp_ptr))
12217		return -ENOMEM;
12218
12219	per_cpu(system_page_pool, cpuid) = pp_ptr;
12220#endif
12221	return 0;
12222}
12223
12224static int backlog_napi_should_run(unsigned int cpu)
12225{
12226	struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu);
12227	struct napi_struct *napi = &sd->backlog;
12228
12229	return test_bit(NAPI_STATE_SCHED_THREADED, &napi->state);
12230}
12231
12232static void run_backlog_napi(unsigned int cpu)
12233{
12234	struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu);
12235
12236	napi_threaded_poll_loop(&sd->backlog);
12237}
12238
12239static void backlog_napi_setup(unsigned int cpu)
12240{
12241	struct softnet_data *sd = per_cpu_ptr(&softnet_data, cpu);
12242	struct napi_struct *napi = &sd->backlog;
12243
12244	napi->thread = this_cpu_read(backlog_napi);
12245	set_bit(NAPI_STATE_THREADED, &napi->state);
12246}
12247
12248static struct smp_hotplug_thread backlog_threads = {
12249	.store			= &backlog_napi,
12250	.thread_should_run	= backlog_napi_should_run,
12251	.thread_fn		= run_backlog_napi,
12252	.thread_comm		= "backlog_napi/%u",
12253	.setup			= backlog_napi_setup,
12254};
12255
12256/*
12257 *       This is called single threaded during boot, so no need
12258 *       to take the rtnl semaphore.
12259 */
12260static int __init net_dev_init(void)
12261{
12262	int i, rc = -ENOMEM;
12263
12264	BUG_ON(!dev_boot_phase);
12265
12266	net_dev_struct_check();
12267
12268	if (dev_proc_init())
12269		goto out;
12270
12271	if (netdev_kobject_init())
12272		goto out;
12273
 
12274	for (i = 0; i < PTYPE_HASH_SIZE; i++)
12275		INIT_LIST_HEAD(&ptype_base[i]);
12276
12277	if (register_pernet_subsys(&netdev_net_ops))
12278		goto out;
12279
12280	/*
12281	 *	Initialise the packet receive queues.
12282	 */
12283
12284	for_each_possible_cpu(i) {
12285		struct work_struct *flush = per_cpu_ptr(&flush_works, i);
12286		struct softnet_data *sd = &per_cpu(softnet_data, i);
12287
12288		INIT_WORK(flush, flush_backlog);
12289
12290		skb_queue_head_init(&sd->input_pkt_queue);
12291		skb_queue_head_init(&sd->process_queue);
12292#ifdef CONFIG_XFRM_OFFLOAD
12293		skb_queue_head_init(&sd->xfrm_backlog);
12294#endif
12295		INIT_LIST_HEAD(&sd->poll_list);
 
12296		sd->output_queue_tailp = &sd->output_queue;
12297#ifdef CONFIG_RPS
12298		INIT_CSD(&sd->csd, rps_trigger_softirq, sd);
 
 
12299		sd->cpu = i;
12300#endif
12301		INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd);
12302		spin_lock_init(&sd->defer_lock);
12303
12304		init_gro_hash(&sd->backlog);
12305		sd->backlog.poll = process_backlog;
12306		sd->backlog.weight = weight_p;
12307		INIT_LIST_HEAD(&sd->backlog.poll_list);
12308
12309		if (net_page_pool_create(i))
12310			goto out;
12311	}
12312	if (use_backlog_threads())
12313		smpboot_register_percpu_thread(&backlog_threads);
12314
12315	dev_boot_phase = 0;
12316
12317	/* The loopback device is special if any other network devices
12318	 * is present in a network namespace the loopback device must
12319	 * be present. Since we now dynamically allocate and free the
12320	 * loopback device ensure this invariant is maintained by
12321	 * keeping the loopback device as the first device on the
12322	 * list of network devices.  Ensuring the loopback devices
12323	 * is the first device that appears and the last network device
12324	 * that disappears.
12325	 */
12326	if (register_pernet_device(&loopback_net_ops))
12327		goto out;
12328
12329	if (register_pernet_device(&default_device_ops))
12330		goto out;
12331
12332	open_softirq(NET_TX_SOFTIRQ, net_tx_action);
12333	open_softirq(NET_RX_SOFTIRQ, net_rx_action);
12334
12335	rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead",
12336				       NULL, dev_cpu_dead);
12337	WARN_ON(rc < 0);
12338	rc = 0;
12339
12340	/* avoid static key IPIs to isolated CPUs */
12341	if (housekeeping_enabled(HK_TYPE_MISC))
12342		net_enable_timestamp();
12343out:
12344	if (rc < 0) {
12345		for_each_possible_cpu(i) {
12346			struct page_pool *pp_ptr;
12347
12348			pp_ptr = per_cpu(system_page_pool, i);
12349			if (!pp_ptr)
12350				continue;
12351
12352			page_pool_destroy(pp_ptr);
12353			per_cpu(system_page_pool, i) = NULL;
12354		}
12355	}
12356
12357	return rc;
12358}
12359
12360subsys_initcall(net_dev_init);
v3.1
 
   1/*
   2 * 	NET3	Protocol independent device support routines.
   3 *
   4 *		This program is free software; you can redistribute it and/or
   5 *		modify it under the terms of the GNU General Public License
   6 *		as published by the Free Software Foundation; either version
   7 *		2 of the License, or (at your option) any later version.
   8 *
   9 *	Derived from the non IP parts of dev.c 1.0.19
  10 * 		Authors:	Ross Biro
  11 *				Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12 *				Mark Evans, <evansmp@uhura.aston.ac.uk>
  13 *
  14 *	Additional Authors:
  15 *		Florian la Roche <rzsfl@rz.uni-sb.de>
  16 *		Alan Cox <gw4pts@gw4pts.ampr.org>
  17 *		David Hinds <dahinds@users.sourceforge.net>
  18 *		Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
  19 *		Adam Sulmicki <adam@cfar.umd.edu>
  20 *              Pekka Riikonen <priikone@poesidon.pspt.fi>
  21 *
  22 *	Changes:
  23 *              D.J. Barrow     :       Fixed bug where dev->refcnt gets set
  24 *              			to 2 if register_netdev gets called
  25 *              			before net_dev_init & also removed a
  26 *              			few lines of code in the process.
  27 *		Alan Cox	:	device private ioctl copies fields back.
  28 *		Alan Cox	:	Transmit queue code does relevant
  29 *					stunts to keep the queue safe.
  30 *		Alan Cox	:	Fixed double lock.
  31 *		Alan Cox	:	Fixed promisc NULL pointer trap
  32 *		????????	:	Support the full private ioctl range
  33 *		Alan Cox	:	Moved ioctl permission check into
  34 *					drivers
  35 *		Tim Kordas	:	SIOCADDMULTI/SIOCDELMULTI
  36 *		Alan Cox	:	100 backlog just doesn't cut it when
  37 *					you start doing multicast video 8)
  38 *		Alan Cox	:	Rewrote net_bh and list manager.
  39 *		Alan Cox	: 	Fix ETH_P_ALL echoback lengths.
  40 *		Alan Cox	:	Took out transmit every packet pass
  41 *					Saved a few bytes in the ioctl handler
  42 *		Alan Cox	:	Network driver sets packet type before
  43 *					calling netif_rx. Saves a function
  44 *					call a packet.
  45 *		Alan Cox	:	Hashed net_bh()
  46 *		Richard Kooijman:	Timestamp fixes.
  47 *		Alan Cox	:	Wrong field in SIOCGIFDSTADDR
  48 *		Alan Cox	:	Device lock protection.
  49 *		Alan Cox	: 	Fixed nasty side effect of device close
  50 *					changes.
  51 *		Rudi Cilibrasi	:	Pass the right thing to
  52 *					set_mac_address()
  53 *		Dave Miller	:	32bit quantity for the device lock to
  54 *					make it work out on a Sparc.
  55 *		Bjorn Ekwall	:	Added KERNELD hack.
  56 *		Alan Cox	:	Cleaned up the backlog initialise.
  57 *		Craig Metz	:	SIOCGIFCONF fix if space for under
  58 *					1 device.
  59 *	    Thomas Bogendoerfer :	Return ENODEV for dev_open, if there
  60 *					is no device open function.
  61 *		Andi Kleen	:	Fix error reporting for SIOCGIFCONF
  62 *	    Michael Chastain	:	Fix signed/unsigned for SIOCGIFCONF
  63 *		Cyrus Durgin	:	Cleaned for KMOD
  64 *		Adam Sulmicki   :	Bug Fix : Network Device Unload
  65 *					A network device unload needs to purge
  66 *					the backlog queue.
  67 *	Paul Rusty Russell	:	SIOCSIFNAME
  68 *              Pekka Riikonen  :	Netdev boot-time settings code
  69 *              Andrew Morton   :       Make unregister_netdevice wait
  70 *              			indefinitely on dev->refcnt
  71 * 		J Hadi Salim	:	- Backlog queue sampling
  72 *				        - netif_rx() feedback
  73 */
  74
  75#include <asm/uaccess.h>
  76#include <asm/system.h>
  77#include <linux/bitops.h>
  78#include <linux/capability.h>
  79#include <linux/cpu.h>
  80#include <linux/types.h>
  81#include <linux/kernel.h>
  82#include <linux/hash.h>
  83#include <linux/slab.h>
  84#include <linux/sched.h>
 
 
 
  85#include <linux/mutex.h>
 
  86#include <linux/string.h>
  87#include <linux/mm.h>
  88#include <linux/socket.h>
  89#include <linux/sockios.h>
  90#include <linux/errno.h>
  91#include <linux/interrupt.h>
  92#include <linux/if_ether.h>
  93#include <linux/netdevice.h>
  94#include <linux/etherdevice.h>
  95#include <linux/ethtool.h>
  96#include <linux/notifier.h>
  97#include <linux/skbuff.h>
 
 
 
  98#include <net/net_namespace.h>
  99#include <net/sock.h>
 
 100#include <linux/rtnetlink.h>
 101#include <linux/proc_fs.h>
 102#include <linux/seq_file.h>
 103#include <linux/stat.h>
 
 104#include <net/dst.h>
 
 
 105#include <net/pkt_sched.h>
 
 106#include <net/checksum.h>
 107#include <net/xfrm.h>
 
 108#include <linux/highmem.h>
 109#include <linux/init.h>
 110#include <linux/kmod.h>
 111#include <linux/module.h>
 112#include <linux/netpoll.h>
 113#include <linux/rcupdate.h>
 114#include <linux/delay.h>
 115#include <net/wext.h>
 116#include <net/iw_handler.h>
 117#include <asm/current.h>
 118#include <linux/audit.h>
 119#include <linux/dmaengine.h>
 120#include <linux/err.h>
 121#include <linux/ctype.h>
 122#include <linux/if_arp.h>
 123#include <linux/if_vlan.h>
 124#include <linux/ip.h>
 125#include <net/ip.h>
 
 126#include <linux/ipv6.h>
 127#include <linux/in.h>
 128#include <linux/jhash.h>
 129#include <linux/random.h>
 130#include <trace/events/napi.h>
 131#include <trace/events/net.h>
 132#include <trace/events/skb.h>
 133#include <linux/pci.h>
 
 134#include <linux/inetdevice.h>
 135#include <linux/cpu_rmap.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 136
 
 
 137#include "net-sysfs.h"
 138
 139/* Instead of increasing this, you should create a hash table. */
 140#define MAX_GRO_SKBS 8
 141
 142/* This should be increased if a protocol with a bigger head is added. */
 143#define GRO_MAX_HEAD (MAX_HEADER + 128)
 
 
 144
 145/*
 146 *	The list of packet types we will receive (as opposed to discard)
 147 *	and the routines to invoke.
 148 *
 149 *	Why 16. Because with 16 the only overlap we get on a hash of the
 150 *	low nibble of the protocol value is RARP/SNAP/X.25.
 151 *
 152 *      NOTE:  That is no longer true with the addition of VLAN tags.  Not
 153 *             sure which should go first, but I bet it won't make much
 154 *             difference if we are running VLANs.  The good news is that
 155 *             this protocol won't be in the list unless compiled in, so
 156 *             the average user (w/out VLANs) will not be adversely affected.
 157 *             --BLG
 158 *
 159 *		0800	IP
 160 *		8100    802.1Q VLAN
 161 *		0001	802.3
 162 *		0002	AX.25
 163 *		0004	802.2
 164 *		8035	RARP
 165 *		0005	SNAP
 166 *		0805	X.25
 167 *		0806	ARP
 168 *		8137	IPX
 169 *		0009	Localtalk
 170 *		86DD	IPv6
 171 */
 172
 173#define PTYPE_HASH_SIZE	(16)
 174#define PTYPE_HASH_MASK	(PTYPE_HASH_SIZE - 1)
 175
 176static DEFINE_SPINLOCK(ptype_lock);
 177static struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
 178static struct list_head ptype_all __read_mostly;	/* Taps */
 179
 180/*
 181 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
 182 * semaphore.
 183 *
 184 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
 185 *
 186 * Writers must hold the rtnl semaphore while they loop through the
 187 * dev_base_head list, and hold dev_base_lock for writing when they do the
 188 * actual updates.  This allows pure readers to access the list even
 189 * while a writer is preparing to update it.
 190 *
 191 * To put it another way, dev_base_lock is held for writing only to
 192 * protect against pure readers; the rtnl semaphore provides the
 193 * protection against other writers.
 194 *
 195 * See, for example usages, register_netdevice() and
 196 * unregister_netdevice(), which must be called with the rtnl
 197 * semaphore held.
 198 */
 199DEFINE_RWLOCK(dev_base_lock);
 200EXPORT_SYMBOL(dev_base_lock);
 201
 202static inline void dev_base_seq_inc(struct net *net)
 203{
 204	while (++net->dev_base_seq == 0);
 
 
 205}
 206
 207static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
 208{
 209	unsigned hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
 
 210	return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
 211}
 212
 213static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
 214{
 215	return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
 216}
 217
 218static inline void rps_lock(struct softnet_data *sd)
 
 
 
 
 219{
 220#ifdef CONFIG_RPS
 221	spin_lock(&sd->input_pkt_queue.lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 222#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 223}
 224
 225static inline void rps_unlock(struct softnet_data *sd)
 226{
 227#ifdef CONFIG_RPS
 228	spin_unlock(&sd->input_pkt_queue.lock);
 229#endif
 
 
 
 230}
 231
 232/* Device list insertion */
 233static int list_netdevice(struct net_device *dev)
 234{
 
 235	struct net *net = dev_net(dev);
 236
 237	ASSERT_RTNL();
 238
 239	write_lock_bh(&dev_base_lock);
 240	list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
 241	hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
 242	hlist_add_head_rcu(&dev->index_hlist,
 243			   dev_index_hash(net, dev->ifindex));
 244	write_unlock_bh(&dev_base_lock);
 
 
 
 
 
 245
 246	dev_base_seq_inc(net);
 247
 248	return 0;
 249}
 250
 251/* Device list removal
 252 * caller must respect a RCU grace period before freeing/reusing dev
 253 */
 254static void unlist_netdevice(struct net_device *dev)
 255{
 
 
 
 256	ASSERT_RTNL();
 257
 
 
 
 
 
 258	/* Unlink dev from the device chain */
 259	write_lock_bh(&dev_base_lock);
 260	list_del_rcu(&dev->dev_list);
 261	hlist_del_rcu(&dev->name_hlist);
 262	hlist_del_rcu(&dev->index_hlist);
 263	write_unlock_bh(&dev_base_lock);
 264
 265	dev_base_seq_inc(dev_net(dev));
 266}
 267
 268/*
 269 *	Our notifier list
 270 */
 271
 272static RAW_NOTIFIER_HEAD(netdev_chain);
 273
 274/*
 275 *	Device drivers call our routines to queue packets here. We empty the
 276 *	queue in the local softnet handler.
 277 */
 278
 279DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
 
 
 280EXPORT_PER_CPU_SYMBOL(softnet_data);
 281
 
 
 
 
 
 
 282#ifdef CONFIG_LOCKDEP
 283/*
 284 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
 285 * according to dev->type
 286 */
 287static const unsigned short netdev_lock_type[] =
 288	{ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
 289	 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
 290	 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
 291	 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
 292	 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
 293	 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
 294	 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
 295	 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
 296	 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
 297	 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
 298	 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
 299	 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
 300	 ARPHRD_FCFABRIC, ARPHRD_IEEE802_TR, ARPHRD_IEEE80211,
 301	 ARPHRD_IEEE80211_PRISM, ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET,
 302	 ARPHRD_PHONET_PIPE, ARPHRD_IEEE802154,
 303	 ARPHRD_VOID, ARPHRD_NONE};
 304
 305static const char *const netdev_lock_name[] =
 306	{"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
 307	 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
 308	 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
 309	 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
 310	 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
 311	 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
 312	 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
 313	 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
 314	 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
 315	 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
 316	 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
 317	 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
 318	 "_xmit_FCFABRIC", "_xmit_IEEE802_TR", "_xmit_IEEE80211",
 319	 "_xmit_IEEE80211_PRISM", "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET",
 320	 "_xmit_PHONET_PIPE", "_xmit_IEEE802154",
 321	 "_xmit_VOID", "_xmit_NONE"};
 322
 323static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
 324static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
 325
 326static inline unsigned short netdev_lock_pos(unsigned short dev_type)
 327{
 328	int i;
 329
 330	for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
 331		if (netdev_lock_type[i] == dev_type)
 332			return i;
 333	/* the last key is used by default */
 334	return ARRAY_SIZE(netdev_lock_type) - 1;
 335}
 336
 337static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
 338						 unsigned short dev_type)
 339{
 340	int i;
 341
 342	i = netdev_lock_pos(dev_type);
 343	lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
 344				   netdev_lock_name[i]);
 345}
 346
 347static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
 348{
 349	int i;
 350
 351	i = netdev_lock_pos(dev->type);
 352	lockdep_set_class_and_name(&dev->addr_list_lock,
 353				   &netdev_addr_lock_key[i],
 354				   netdev_lock_name[i]);
 355}
 356#else
 357static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
 358						 unsigned short dev_type)
 359{
 360}
 
 361static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
 362{
 363}
 364#endif
 365
 366/*******************************************************************************
 
 
 
 
 367
 368		Protocol management and registration routines
 369
 370*******************************************************************************/
 371
 372/*
 373 *	Add a protocol ID to the list. Now that the input handler is
 374 *	smarter we can dispense with all the messy stuff that used to be
 375 *	here.
 376 *
 377 *	BEWARE!!! Protocol handlers, mangling input packets,
 378 *	MUST BE last in hash buckets and checking protocol handlers
 379 *	MUST start from promiscuous ptype_all chain in net_bh.
 380 *	It is true now, do not change it.
 381 *	Explanation follows: if protocol handler, mangling packet, will
 382 *	be the first on list, it is not able to sense, that packet
 383 *	is cloned and should be copied-on-write, so that it will
 384 *	change it and subsequent readers will get broken packet.
 385 *							--ANK (980803)
 386 */
 387
 388static inline struct list_head *ptype_head(const struct packet_type *pt)
 389{
 390	if (pt->type == htons(ETH_P_ALL))
 391		return &ptype_all;
 392	else
 393		return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
 
 394}
 395
 396/**
 397 *	dev_add_pack - add packet handler
 398 *	@pt: packet type declaration
 399 *
 400 *	Add a protocol handler to the networking stack. The passed &packet_type
 401 *	is linked into kernel lists and may not be freed until it has been
 402 *	removed from the kernel lists.
 403 *
 404 *	This call does not sleep therefore it can not
 405 *	guarantee all CPU's that are in middle of receiving packets
 406 *	will see the new packet type (until the next received packet).
 407 */
 408
 409void dev_add_pack(struct packet_type *pt)
 410{
 411	struct list_head *head = ptype_head(pt);
 412
 413	spin_lock(&ptype_lock);
 414	list_add_rcu(&pt->list, head);
 415	spin_unlock(&ptype_lock);
 416}
 417EXPORT_SYMBOL(dev_add_pack);
 418
 419/**
 420 *	__dev_remove_pack	 - remove packet handler
 421 *	@pt: packet type declaration
 422 *
 423 *	Remove a protocol handler that was previously added to the kernel
 424 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
 425 *	from the kernel lists and can be freed or reused once this function
 426 *	returns.
 427 *
 428 *      The packet type might still be in use by receivers
 429 *	and must not be freed until after all the CPU's have gone
 430 *	through a quiescent state.
 431 */
 432void __dev_remove_pack(struct packet_type *pt)
 433{
 434	struct list_head *head = ptype_head(pt);
 435	struct packet_type *pt1;
 436
 437	spin_lock(&ptype_lock);
 438
 439	list_for_each_entry(pt1, head, list) {
 440		if (pt == pt1) {
 441			list_del_rcu(&pt->list);
 442			goto out;
 443		}
 444	}
 445
 446	printk(KERN_WARNING "dev_remove_pack: %p not found.\n", pt);
 447out:
 448	spin_unlock(&ptype_lock);
 449}
 450EXPORT_SYMBOL(__dev_remove_pack);
 451
 452/**
 453 *	dev_remove_pack	 - remove packet handler
 454 *	@pt: packet type declaration
 455 *
 456 *	Remove a protocol handler that was previously added to the kernel
 457 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
 458 *	from the kernel lists and can be freed or reused once this function
 459 *	returns.
 460 *
 461 *	This call sleeps to guarantee that no CPU is looking at the packet
 462 *	type after return.
 463 */
 464void dev_remove_pack(struct packet_type *pt)
 465{
 466	__dev_remove_pack(pt);
 467
 468	synchronize_net();
 469}
 470EXPORT_SYMBOL(dev_remove_pack);
 471
 472/******************************************************************************
 473
 474		      Device Boot-time Settings Routines
 475
 476*******************************************************************************/
 477
 478/* Boot time configuration table */
 479static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
 480
 481/**
 482 *	netdev_boot_setup_add	- add new setup entry
 483 *	@name: name of the device
 484 *	@map: configured settings for the device
 485 *
 486 *	Adds new setup entry to the dev_boot_setup list.  The function
 487 *	returns 0 on error and 1 on success.  This is a generic routine to
 488 *	all netdevices.
 489 */
 490static int netdev_boot_setup_add(char *name, struct ifmap *map)
 
 491{
 492	struct netdev_boot_setup *s;
 493	int i;
 494
 495	s = dev_boot_setup;
 496	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
 497		if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
 498			memset(s[i].name, 0, sizeof(s[i].name));
 499			strlcpy(s[i].name, name, IFNAMSIZ);
 500			memcpy(&s[i].map, map, sizeof(s[i].map));
 501			break;
 502		}
 503	}
 504
 505	return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
 506}
 
 507
 508/**
 509 *	netdev_boot_setup_check	- check boot time settings
 510 *	@dev: the netdevice
 
 511 *
 512 * 	Check boot time settings for the device.
 513 *	The found settings are set for the device to be used
 514 *	later in the device probing.
 515 *	Returns 0 if no settings found, 1 if they are.
 516 */
 517int netdev_boot_setup_check(struct net_device *dev)
 518{
 519	struct netdev_boot_setup *s = dev_boot_setup;
 520	int i;
 
 
 
 
 
 
 
 
 521
 522	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
 523		if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
 524		    !strcmp(dev->name, s[i].name)) {
 525			dev->irq 	= s[i].map.irq;
 526			dev->base_addr 	= s[i].map.base_addr;
 527			dev->mem_start 	= s[i].map.mem_start;
 528			dev->mem_end 	= s[i].map.mem_end;
 529			return 1;
 530		}
 531	}
 532	return 0;
 533}
 534EXPORT_SYMBOL(netdev_boot_setup_check);
 
 
 
 
 535
 
 
 
 
 
 536
 537/**
 538 *	netdev_boot_base	- get address from boot time settings
 539 *	@prefix: prefix for network device
 540 *	@unit: id for network device
 541 *
 542 * 	Check boot time settings for the base address of device.
 543 *	The found settings are set for the device to be used
 544 *	later in the device probing.
 545 *	Returns 0 if no settings found.
 546 */
 547unsigned long netdev_boot_base(const char *prefix, int unit)
 548{
 549	const struct netdev_boot_setup *s = dev_boot_setup;
 550	char name[IFNAMSIZ];
 551	int i;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 552
 553	sprintf(name, "%s%d", prefix, unit);
 
 554
 555	/*
 556	 * If device already registered then return base of 1
 557	 * to indicate not to probe for this interface
 558	 */
 559	if (__dev_get_by_name(&init_net, name))
 560		return 1;
 561
 562	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
 563		if (!strcmp(name, s[i].name))
 564			return s[i].map.base_addr;
 565	return 0;
 566}
 
 567
 568/*
 569 * Saves at boot time configured settings for any netdevice.
 570 */
 571int __init netdev_boot_setup(char *str)
 572{
 573	int ints[5];
 574	struct ifmap map;
 575
 576	str = get_options(str, ARRAY_SIZE(ints), ints);
 577	if (!str || !*str)
 578		return 0;
 579
 580	/* Save settings */
 581	memset(&map, 0, sizeof(map));
 582	if (ints[0] > 0)
 583		map.irq = ints[1];
 584	if (ints[0] > 1)
 585		map.base_addr = ints[2];
 586	if (ints[0] > 2)
 587		map.mem_start = ints[3];
 588	if (ints[0] > 3)
 589		map.mem_end = ints[4];
 590
 591	/* Add new entry to the list */
 592	return netdev_boot_setup_add(str, &map);
 593}
 594
 595__setup("netdev=", netdev_boot_setup);
 
 
 
 596
 597/*******************************************************************************
 
 
 598
 599			    Device Interface Subroutines
 
 
 
 600
 601*******************************************************************************/
 
 602
 603/**
 604 *	__dev_get_by_name	- find a device by its name
 605 *	@net: the applicable net namespace
 606 *	@name: name to find
 607 *
 608 *	Find an interface by name. Must be called under RTNL semaphore
 609 *	or @dev_base_lock. If the name is found a pointer to the device
 610 *	is returned. If the name is not found then %NULL is returned. The
 611 *	reference counters are not incremented so the caller must be
 612 *	careful with locks.
 613 */
 614
 615struct net_device *__dev_get_by_name(struct net *net, const char *name)
 616{
 617	struct hlist_node *p;
 618	struct net_device *dev;
 619	struct hlist_head *head = dev_name_hash(net, name);
 620
 621	hlist_for_each_entry(dev, p, head, name_hlist)
 622		if (!strncmp(dev->name, name, IFNAMSIZ))
 623			return dev;
 624
 625	return NULL;
 
 626}
 627EXPORT_SYMBOL(__dev_get_by_name);
 628
 629/**
 630 *	dev_get_by_name_rcu	- find a device by its name
 631 *	@net: the applicable net namespace
 632 *	@name: name to find
 633 *
 634 *	Find an interface by name.
 635 *	If the name is found a pointer to the device is returned.
 636 * 	If the name is not found then %NULL is returned.
 637 *	The reference counters are not incremented so the caller must be
 638 *	careful with locks. The caller must hold RCU lock.
 639 */
 640
 641struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
 642{
 643	struct hlist_node *p;
 
 
 
 
 
 
 
 
 
 644	struct net_device *dev;
 645	struct hlist_head *head = dev_name_hash(net, name);
 646
 647	hlist_for_each_entry_rcu(dev, p, head, name_hlist)
 648		if (!strncmp(dev->name, name, IFNAMSIZ))
 649			return dev;
 650
 651	return NULL;
 652}
 653EXPORT_SYMBOL(dev_get_by_name_rcu);
 654
 655/**
 656 *	dev_get_by_name		- find a device by its name
 657 *	@net: the applicable net namespace
 658 *	@name: name to find
 
 
 659 *
 660 *	Find an interface by name. This can be called from any
 661 *	context and does its own locking. The returned handle has
 662 *	the usage count incremented and the caller must use dev_put() to
 663 *	release it when it is no longer needed. %NULL is returned if no
 664 *	matching device is found.
 665 */
 666
 667struct net_device *dev_get_by_name(struct net *net, const char *name)
 668{
 669	struct net_device *dev;
 670
 671	rcu_read_lock();
 672	dev = dev_get_by_name_rcu(net, name);
 673	if (dev)
 674		dev_hold(dev);
 675	rcu_read_unlock();
 676	return dev;
 677}
 678EXPORT_SYMBOL(dev_get_by_name);
 679
 680/**
 681 *	__dev_get_by_index - find a device by its ifindex
 682 *	@net: the applicable net namespace
 683 *	@ifindex: index of device
 684 *
 685 *	Search for an interface by index. Returns %NULL if the device
 686 *	is not found or a pointer to the device. The device has not
 687 *	had its reference counter increased so the caller must be careful
 688 *	about locking. The caller must hold either the RTNL semaphore
 689 *	or @dev_base_lock.
 690 */
 691
 692struct net_device *__dev_get_by_index(struct net *net, int ifindex)
 693{
 694	struct hlist_node *p;
 695	struct net_device *dev;
 696	struct hlist_head *head = dev_index_hash(net, ifindex);
 697
 698	hlist_for_each_entry(dev, p, head, index_hlist)
 699		if (dev->ifindex == ifindex)
 700			return dev;
 701
 702	return NULL;
 703}
 704EXPORT_SYMBOL(__dev_get_by_index);
 705
 706/**
 707 *	dev_get_by_index_rcu - find a device by its ifindex
 708 *	@net: the applicable net namespace
 709 *	@ifindex: index of device
 710 *
 711 *	Search for an interface by index. Returns %NULL if the device
 712 *	is not found or a pointer to the device. The device has not
 713 *	had its reference counter increased so the caller must be careful
 714 *	about locking. The caller must hold RCU lock.
 715 */
 716
 717struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
 718{
 719	struct hlist_node *p;
 720	struct net_device *dev;
 721	struct hlist_head *head = dev_index_hash(net, ifindex);
 722
 723	hlist_for_each_entry_rcu(dev, p, head, index_hlist)
 724		if (dev->ifindex == ifindex)
 725			return dev;
 726
 727	return NULL;
 728}
 729EXPORT_SYMBOL(dev_get_by_index_rcu);
 730
 
 
 
 
 
 
 
 
 
 
 
 
 731
 732/**
 733 *	dev_get_by_index - find a device by its ifindex
 734 *	@net: the applicable net namespace
 735 *	@ifindex: index of device
 
 
 736 *
 737 *	Search for an interface by index. Returns NULL if the device
 738 *	is not found or a pointer to the device. The device returned has
 739 *	had a reference added and the pointer is safe until the user calls
 740 *	dev_put to indicate they have finished with it.
 741 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 742
 743struct net_device *dev_get_by_index(struct net *net, int ifindex)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 744{
 745	struct net_device *dev;
 
 746
 747	rcu_read_lock();
 
 748	dev = dev_get_by_index_rcu(net, ifindex);
 749	if (dev)
 750		dev_hold(dev);
 
 
 
 
 
 
 
 751	rcu_read_unlock();
 752	return dev;
 
 
 
 
 
 
 753}
 754EXPORT_SYMBOL(dev_get_by_index);
 755
 756/**
 757 *	dev_getbyhwaddr_rcu - find a device by its hardware address
 758 *	@net: the applicable net namespace
 759 *	@type: media type of device
 760 *	@ha: hardware address
 761 *
 762 *	Search for an interface by MAC address. Returns NULL if the device
 763 *	is not found or a pointer to the device.
 764 *	The caller must hold RCU or RTNL.
 765 *	The returned device has not had its ref count increased
 766 *	and the caller must therefore be careful about locking
 767 *
 768 */
 769
 770struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
 771				       const char *ha)
 772{
 773	struct net_device *dev;
 774
 775	for_each_netdev_rcu(net, dev)
 776		if (dev->type == type &&
 777		    !memcmp(dev->dev_addr, ha, dev->addr_len))
 778			return dev;
 779
 780	return NULL;
 781}
 782EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
 783
 784struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
 
 
 
 
 
 
 
 
 
 
 
 
 
 785{
 786	struct net_device *dev;
 787
 788	ASSERT_RTNL();
 789	for_each_netdev(net, dev)
 790		if (dev->type == type)
 791			return dev;
 792
 793	return NULL;
 794}
 795EXPORT_SYMBOL(__dev_getfirstbyhwtype);
 796
 797struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
 798{
 799	struct net_device *dev, *ret = NULL;
 800
 801	rcu_read_lock();
 802	for_each_netdev_rcu(net, dev)
 803		if (dev->type == type) {
 804			dev_hold(dev);
 805			ret = dev;
 806			break;
 807		}
 808	rcu_read_unlock();
 809	return ret;
 810}
 811EXPORT_SYMBOL(dev_getfirstbyhwtype);
 812
 813/**
 814 *	dev_get_by_flags_rcu - find any device with given flags
 815 *	@net: the applicable net namespace
 816 *	@if_flags: IFF_* values
 817 *	@mask: bitmask of bits in if_flags to check
 818 *
 819 *	Search for any interface with the given flags. Returns NULL if a device
 820 *	is not found or a pointer to the device. Must be called inside
 821 *	rcu_read_lock(), and result refcount is unchanged.
 822 */
 823
 824struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags,
 825				    unsigned short mask)
 826{
 827	struct net_device *dev, *ret;
 828
 
 
 829	ret = NULL;
 830	for_each_netdev_rcu(net, dev) {
 831		if (((dev->flags ^ if_flags) & mask) == 0) {
 832			ret = dev;
 833			break;
 834		}
 835	}
 836	return ret;
 837}
 838EXPORT_SYMBOL(dev_get_by_flags_rcu);
 839
 840/**
 841 *	dev_valid_name - check if name is okay for network device
 842 *	@name: name string
 843 *
 844 *	Network device names need to be valid file names to
 845 *	to allow sysfs to work.  We also disallow any kind of
 846 *	whitespace.
 847 */
 848int dev_valid_name(const char *name)
 849{
 850	if (*name == '\0')
 851		return 0;
 852	if (strlen(name) >= IFNAMSIZ)
 853		return 0;
 854	if (!strcmp(name, ".") || !strcmp(name, ".."))
 855		return 0;
 856
 857	while (*name) {
 858		if (*name == '/' || isspace(*name))
 859			return 0;
 860		name++;
 861	}
 862	return 1;
 863}
 864EXPORT_SYMBOL(dev_valid_name);
 865
 866/**
 867 *	__dev_alloc_name - allocate a name for a device
 868 *	@net: network namespace to allocate the device name in
 869 *	@name: name format string
 870 *	@buf:  scratch buffer and result name string
 871 *
 872 *	Passed a format string - eg "lt%d" it will try and find a suitable
 873 *	id. It scans list of devices to build up a free map, then chooses
 874 *	the first empty slot. The caller must hold the dev_base or rtnl lock
 875 *	while allocating the name and adding the device in order to avoid
 876 *	duplicates.
 877 *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
 878 *	Returns the number of the unit assigned or a negative errno code.
 879 */
 880
 881static int __dev_alloc_name(struct net *net, const char *name, char *buf)
 882{
 883	int i = 0;
 884	const char *p;
 885	const int max_netdevices = 8*PAGE_SIZE;
 886	unsigned long *inuse;
 887	struct net_device *d;
 
 
 
 
 
 
 
 
 888
 889	p = strnchr(name, IFNAMSIZ-1, '%');
 890	if (p) {
 891		/*
 892		 * Verify the string as this thing may have come from
 893		 * the user.  There must be either one "%d" and no other "%"
 894		 * characters.
 895		 */
 896		if (p[1] != 'd' || strchr(p + 2, '%'))
 897			return -EINVAL;
 898
 899		/* Use one page as a bit array of possible slots */
 900		inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
 901		if (!inuse)
 902			return -ENOMEM;
 903
 904		for_each_netdev(net, d) {
 905			if (!sscanf(d->name, name, &i))
 906				continue;
 907			if (i < 0 || i >= max_netdevices)
 908				continue;
 909
 910			/*  avoid cases where sscanf is not exact inverse of printf */
 911			snprintf(buf, IFNAMSIZ, name, i);
 912			if (!strncmp(buf, d->name, IFNAMSIZ))
 913				set_bit(i, inuse);
 914		}
 
 
 
 
 915
 916		i = find_first_zero_bit(inuse, max_netdevices);
 917		free_page((unsigned long) inuse);
 
 
 918	}
 919
 920	if (buf != name)
 921		snprintf(buf, IFNAMSIZ, name, i);
 922	if (!__dev_get_by_name(net, buf))
 923		return i;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 924
 925	/* It is possible to run out of possible slots
 926	 * when the name is long and there isn't enough space left
 927	 * for the digits, or if all bits are used.
 928	 */
 929	return -ENFILE;
 930}
 931
 932/**
 933 *	dev_alloc_name - allocate a name for a device
 934 *	@dev: device
 935 *	@name: name format string
 936 *
 937 *	Passed a format string - eg "lt%d" it will try and find a suitable
 938 *	id. It scans list of devices to build up a free map, then chooses
 939 *	the first empty slot. The caller must hold the dev_base or rtnl lock
 940 *	while allocating the name and adding the device in order to avoid
 941 *	duplicates.
 942 *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
 943 *	Returns the number of the unit assigned or a negative errno code.
 944 */
 945
 946int dev_alloc_name(struct net_device *dev, const char *name)
 947{
 948	char buf[IFNAMSIZ];
 949	struct net *net;
 950	int ret;
 951
 952	BUG_ON(!dev_net(dev));
 953	net = dev_net(dev);
 954	ret = __dev_alloc_name(net, name, buf);
 955	if (ret >= 0)
 956		strlcpy(dev->name, buf, IFNAMSIZ);
 957	return ret;
 958}
 959EXPORT_SYMBOL(dev_alloc_name);
 960
 961static int dev_get_valid_name(struct net_device *dev, const char *name)
 
 962{
 963	struct net *net;
 964
 965	BUG_ON(!dev_net(dev));
 966	net = dev_net(dev);
 967
 968	if (!dev_valid_name(name))
 969		return -EINVAL;
 970
 971	if (strchr(name, '%'))
 972		return dev_alloc_name(dev, name);
 973	else if (__dev_get_by_name(net, name))
 974		return -EEXIST;
 975	else if (dev->name != name)
 976		strlcpy(dev->name, name, IFNAMSIZ);
 977
 978	return 0;
 979}
 980
 981/**
 982 *	dev_change_name - change name of a device
 983 *	@dev: device
 984 *	@newname: name (or format string) must be at least IFNAMSIZ
 985 *
 986 *	Change name of a device, can pass format strings "eth%d".
 987 *	for wildcarding.
 988 */
 989int dev_change_name(struct net_device *dev, const char *newname)
 990{
 
 991	char oldname[IFNAMSIZ];
 992	int err = 0;
 993	int ret;
 994	struct net *net;
 995
 996	ASSERT_RTNL();
 997	BUG_ON(!dev_net(dev));
 998
 999	net = dev_net(dev);
1000	if (dev->flags & IFF_UP)
1001		return -EBUSY;
1002
1003	if (strncmp(newname, dev->name, IFNAMSIZ) == 0)
 
 
 
1004		return 0;
 
1005
1006	memcpy(oldname, dev->name, IFNAMSIZ);
1007
1008	err = dev_get_valid_name(dev, newname);
1009	if (err < 0)
 
 
 
 
1010		return err;
 
 
 
 
 
 
 
 
1011
1012rollback:
1013	ret = device_rename(&dev->dev, dev->name);
1014	if (ret) {
 
1015		memcpy(dev->name, oldname, IFNAMSIZ);
 
 
 
1016		return ret;
1017	}
1018
1019	write_lock_bh(&dev_base_lock);
1020	hlist_del_rcu(&dev->name_hlist);
1021	write_unlock_bh(&dev_base_lock);
1022
1023	synchronize_rcu();
1024
1025	write_lock_bh(&dev_base_lock);
1026	hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1027	write_unlock_bh(&dev_base_lock);
1028
1029	ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1030	ret = notifier_to_errno(ret);
1031
1032	if (ret) {
1033		/* err >= 0 after dev_alloc_name() or stores the first errno */
1034		if (err >= 0) {
1035			err = ret;
 
 
1036			memcpy(dev->name, oldname, IFNAMSIZ);
 
 
 
 
1037			goto rollback;
1038		} else {
1039			printk(KERN_ERR
1040			       "%s: name change rollback failed: %d.\n",
1041			       dev->name, ret);
1042		}
1043	}
1044
1045	return err;
1046}
1047
1048/**
1049 *	dev_set_alias - change ifalias of a device
1050 *	@dev: device
1051 *	@alias: name up to IFALIASZ
1052 *	@len: limit of bytes to copy from info
1053 *
1054 *	Set ifalias for a device,
1055 */
1056int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
1057{
1058	ASSERT_RTNL();
1059
1060	if (len >= IFALIASZ)
1061		return -EINVAL;
1062
1063	if (!len) {
1064		if (dev->ifalias) {
1065			kfree(dev->ifalias);
1066			dev->ifalias = NULL;
1067		}
1068		return 0;
 
1069	}
1070
1071	dev->ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
1072	if (!dev->ifalias)
1073		return -ENOMEM;
 
 
 
 
1074
1075	strlcpy(dev->ifalias, alias, len+1);
1076	return len;
1077}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1078
 
 
1079
1080/**
1081 *	netdev_features_change - device changes features
1082 *	@dev: device to cause notification
1083 *
1084 *	Called to indicate a device has changed features.
1085 */
1086void netdev_features_change(struct net_device *dev)
1087{
1088	call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1089}
1090EXPORT_SYMBOL(netdev_features_change);
1091
1092/**
1093 *	netdev_state_change - device changes state
1094 *	@dev: device to cause notification
1095 *
1096 *	Called to indicate a device has changed state. This function calls
1097 *	the notifier chains for netdev_chain and sends a NEWLINK message
1098 *	to the routing socket.
1099 */
1100void netdev_state_change(struct net_device *dev)
1101{
1102	if (dev->flags & IFF_UP) {
1103		call_netdevice_notifiers(NETDEV_CHANGE, dev);
1104		rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
 
 
 
 
 
1105	}
1106}
1107EXPORT_SYMBOL(netdev_state_change);
1108
1109int netdev_bonding_change(struct net_device *dev, unsigned long event)
 
 
 
 
 
 
 
 
 
 
 
1110{
1111	return call_netdevice_notifiers(event, dev);
 
 
1112}
1113EXPORT_SYMBOL(netdev_bonding_change);
1114
1115/**
1116 *	dev_load 	- load a network module
1117 *	@net: the applicable net namespace
1118 *	@name: name of interface
1119 *
1120 *	If a network interface is not present and the process has suitable
1121 *	privileges this function loads the module. If module loading is not
1122 *	available in this kernel then it becomes a nop.
 
 
1123 */
 
 
 
 
 
 
 
 
 
1124
1125void dev_load(struct net *net, const char *name)
1126{
1127	struct net_device *dev;
1128	int no_module;
1129
1130	rcu_read_lock();
1131	dev = dev_get_by_name_rcu(net, name);
1132	rcu_read_unlock();
 
 
 
 
 
 
 
 
1133
1134	no_module = !dev;
1135	if (no_module && capable(CAP_NET_ADMIN))
1136		no_module = request_module("netdev-%s", name);
1137	if (no_module && capable(CAP_SYS_MODULE)) {
1138		if (!request_module("%s", name))
1139			pr_err("Loading kernel module for a network device "
1140"with CAP_SYS_MODULE (deprecated).  Use CAP_NET_ADMIN and alias netdev-%s "
1141"instead\n", name);
1142	}
1143}
1144EXPORT_SYMBOL(dev_load);
1145
1146static int __dev_open(struct net_device *dev)
1147{
1148	const struct net_device_ops *ops = dev->netdev_ops;
1149	int ret;
1150
1151	ASSERT_RTNL();
 
1152
1153	if (!netif_device_present(dev))
1154		return -ENODEV;
 
 
 
 
 
 
 
 
 
 
 
1155
1156	ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
1157	ret = notifier_to_errno(ret);
1158	if (ret)
1159		return ret;
1160
1161	set_bit(__LINK_STATE_START, &dev->state);
1162
1163	if (ops->ndo_validate_addr)
1164		ret = ops->ndo_validate_addr(dev);
1165
1166	if (!ret && ops->ndo_open)
1167		ret = ops->ndo_open(dev);
1168
 
 
1169	if (ret)
1170		clear_bit(__LINK_STATE_START, &dev->state);
1171	else {
1172		dev->flags |= IFF_UP;
1173		net_dmaengine_get();
1174		dev_set_rx_mode(dev);
1175		dev_activate(dev);
 
1176	}
1177
1178	return ret;
1179}
1180
1181/**
1182 *	dev_open	- prepare an interface for use.
1183 *	@dev:	device to open
 
1184 *
1185 *	Takes a device from down to up state. The device's private open
1186 *	function is invoked and then the multicast lists are loaded. Finally
1187 *	the device is moved into the up state and a %NETDEV_UP message is
1188 *	sent to the netdev notifier chain.
1189 *
1190 *	Calling this function on an active interface is a nop. On a failure
1191 *	a negative errno code is returned.
1192 */
1193int dev_open(struct net_device *dev)
1194{
1195	int ret;
1196
1197	if (dev->flags & IFF_UP)
1198		return 0;
1199
1200	ret = __dev_open(dev);
1201	if (ret < 0)
1202		return ret;
1203
1204	rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
1205	call_netdevice_notifiers(NETDEV_UP, dev);
1206
1207	return ret;
1208}
1209EXPORT_SYMBOL(dev_open);
1210
1211static int __dev_close_many(struct list_head *head)
1212{
1213	struct net_device *dev;
1214
1215	ASSERT_RTNL();
1216	might_sleep();
1217
1218	list_for_each_entry(dev, head, unreg_list) {
 
 
 
1219		call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
1220
1221		clear_bit(__LINK_STATE_START, &dev->state);
1222
1223		/* Synchronize to scheduled poll. We cannot touch poll list, it
1224		 * can be even on different cpu. So just clear netif_running().
1225		 *
1226		 * dev->stop() will invoke napi_disable() on all of it's
1227		 * napi_struct instances on this device.
1228		 */
1229		smp_mb__after_clear_bit(); /* Commit netif_running(). */
1230	}
1231
1232	dev_deactivate_many(head);
1233
1234	list_for_each_entry(dev, head, unreg_list) {
1235		const struct net_device_ops *ops = dev->netdev_ops;
1236
1237		/*
1238		 *	Call the device specific close. This cannot fail.
1239		 *	Only if device is UP
1240		 *
1241		 *	We allow it to be called even after a DETACH hot-plug
1242		 *	event.
1243		 */
1244		if (ops->ndo_stop)
1245			ops->ndo_stop(dev);
1246
1247		dev->flags &= ~IFF_UP;
1248		net_dmaengine_put();
1249	}
1250
1251	return 0;
1252}
1253
1254static int __dev_close(struct net_device *dev)
1255{
1256	int retval;
1257	LIST_HEAD(single);
1258
1259	list_add(&dev->unreg_list, &single);
1260	retval = __dev_close_many(&single);
1261	list_del(&single);
1262	return retval;
1263}
1264
1265static int dev_close_many(struct list_head *head)
1266{
1267	struct net_device *dev, *tmp;
1268	LIST_HEAD(tmp_list);
1269
1270	list_for_each_entry_safe(dev, tmp, head, unreg_list)
 
1271		if (!(dev->flags & IFF_UP))
1272			list_move(&dev->unreg_list, &tmp_list);
1273
1274	__dev_close_many(head);
1275
1276	list_for_each_entry(dev, head, unreg_list) {
1277		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
1278		call_netdevice_notifiers(NETDEV_DOWN, dev);
 
 
1279	}
1280
1281	/* rollback_registered_many needs the complete original list */
1282	list_splice(&tmp_list, head);
1283	return 0;
1284}
 
1285
1286/**
1287 *	dev_close - shutdown an interface.
1288 *	@dev: device to shutdown
1289 *
1290 *	This function moves an active device into down state. A
1291 *	%NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
1292 *	is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
1293 *	chain.
1294 */
1295int dev_close(struct net_device *dev)
1296{
1297	if (dev->flags & IFF_UP) {
1298		LIST_HEAD(single);
1299
1300		list_add(&dev->unreg_list, &single);
1301		dev_close_many(&single);
1302		list_del(&single);
1303	}
1304	return 0;
1305}
1306EXPORT_SYMBOL(dev_close);
1307
1308
1309/**
1310 *	dev_disable_lro - disable Large Receive Offload on a device
1311 *	@dev: device
1312 *
1313 *	Disable Large Receive Offload (LRO) on a net device.  Must be
1314 *	called under RTNL.  This is needed if received packets may be
1315 *	forwarded to another interface.
1316 */
1317void dev_disable_lro(struct net_device *dev)
1318{
1319	u32 flags;
 
1320
1321	/*
1322	 * If we're trying to disable lro on a vlan device
1323	 * use the underlying physical device instead
1324	 */
1325	if (is_vlan_dev(dev))
1326		dev = vlan_dev_real_dev(dev);
1327
1328	if (dev->ethtool_ops && dev->ethtool_ops->get_flags)
1329		flags = dev->ethtool_ops->get_flags(dev);
1330	else
1331		flags = ethtool_op_get_flags(dev);
1332
1333	if (!(flags & ETH_FLAG_LRO))
1334		return;
1335
1336	__ethtool_set_flags(dev, flags & ~ETH_FLAG_LRO);
1337	if (unlikely(dev->features & NETIF_F_LRO))
1338		netdev_WARN(dev, "failed to disable LRO!\n");
 
 
 
1339}
1340EXPORT_SYMBOL(dev_disable_lro);
1341
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1342
1343static int dev_boot_phase = 1;
1344
1345/**
1346 *	register_netdevice_notifier - register a network notifier block
1347 *	@nb: notifier
1348 *
1349 *	Register a notifier to be called when network device events occur.
1350 *	The notifier passed is linked into the kernel structures and must
1351 *	not be reused until it has been unregistered. A negative errno code
1352 *	is returned on a failure.
1353 *
1354 * 	When registered all registration and up events are replayed
1355 *	to the new notifier to allow device to have a race free
1356 *	view of the network device list.
1357 */
1358
1359int register_netdevice_notifier(struct notifier_block *nb)
1360{
1361	struct net_device *dev;
1362	struct net_device *last;
1363	struct net *net;
1364	int err;
1365
 
 
1366	rtnl_lock();
1367	err = raw_notifier_chain_register(&netdev_chain, nb);
1368	if (err)
1369		goto unlock;
1370	if (dev_boot_phase)
1371		goto unlock;
1372	for_each_net(net) {
1373		for_each_netdev(net, dev) {
1374			err = nb->notifier_call(nb, NETDEV_REGISTER, dev);
1375			err = notifier_to_errno(err);
1376			if (err)
1377				goto rollback;
1378
1379			if (!(dev->flags & IFF_UP))
1380				continue;
1381
1382			nb->notifier_call(nb, NETDEV_UP, dev);
1383		}
1384	}
1385
1386unlock:
1387	rtnl_unlock();
 
1388	return err;
1389
1390rollback:
1391	last = dev;
1392	for_each_net(net) {
1393		for_each_netdev(net, dev) {
1394			if (dev == last)
1395				break;
1396
1397			if (dev->flags & IFF_UP) {
1398				nb->notifier_call(nb, NETDEV_GOING_DOWN, dev);
1399				nb->notifier_call(nb, NETDEV_DOWN, dev);
1400			}
1401			nb->notifier_call(nb, NETDEV_UNREGISTER, dev);
1402			nb->notifier_call(nb, NETDEV_UNREGISTER_BATCH, dev);
1403		}
1404	}
1405
1406	raw_notifier_chain_unregister(&netdev_chain, nb);
1407	goto unlock;
1408}
1409EXPORT_SYMBOL(register_netdevice_notifier);
1410
1411/**
1412 *	unregister_netdevice_notifier - unregister a network notifier block
1413 *	@nb: notifier
1414 *
1415 *	Unregister a notifier previously registered by
1416 *	register_netdevice_notifier(). The notifier is unlinked into the
1417 *	kernel structures and may then be reused. A negative errno code
1418 *	is returned on a failure.
 
 
 
 
1419 */
1420
1421int unregister_netdevice_notifier(struct notifier_block *nb)
1422{
 
1423	int err;
1424
 
 
1425	rtnl_lock();
1426	err = raw_notifier_chain_unregister(&netdev_chain, nb);
 
 
 
 
 
 
 
1427	rtnl_unlock();
 
1428	return err;
1429}
1430EXPORT_SYMBOL(unregister_netdevice_notifier);
1431
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1432/**
1433 *	call_netdevice_notifiers - call all network notifier blocks
1434 *      @val: value passed unmodified to notifier function
1435 *      @dev: net_device pointer passed unmodified to notifier function
1436 *
1437 *	Call all network notifier blocks.  Parameters and return value
1438 *	are as for raw_notifier_call_chain().
1439 */
1440
1441int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
1442{
1443	ASSERT_RTNL();
1444	return raw_notifier_call_chain(&netdev_chain, val, dev);
1445}
1446EXPORT_SYMBOL(call_netdevice_notifiers);
1447
1448/* When > 0 there are consumers of rx skb time stamps */
1449static atomic_t netstamp_needed = ATOMIC_INIT(0);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1450
1451void net_enable_timestamp(void)
1452{
1453	atomic_inc(&netstamp_needed);
 
 
 
 
 
 
 
 
 
 
 
1454}
1455EXPORT_SYMBOL(net_enable_timestamp);
1456
1457void net_disable_timestamp(void)
1458{
1459	atomic_dec(&netstamp_needed);
 
 
 
 
 
 
 
 
 
 
 
1460}
1461EXPORT_SYMBOL(net_disable_timestamp);
1462
1463static inline void net_timestamp_set(struct sk_buff *skb)
1464{
1465	if (atomic_read(&netstamp_needed))
1466		__net_timestamp(skb);
1467	else
1468		skb->tstamp.tv64 = 0;
1469}
1470
1471static inline void net_timestamp_check(struct sk_buff *skb)
 
 
 
 
 
 
1472{
1473	if (!skb->tstamp.tv64 && atomic_read(&netstamp_needed))
1474		__net_timestamp(skb);
1475}
 
1476
1477static inline bool is_skb_forwardable(struct net_device *dev,
1478				      struct sk_buff *skb)
1479{
1480	unsigned int len;
1481
1482	if (!(dev->flags & IFF_UP))
1483		return false;
 
 
1484
1485	len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
1486	if (skb->len <= len)
1487		return true;
1488
1489	/* if TSO is enabled, we don't care about the length as the packet
1490	 * could be forwarded without being segmented before
1491	 */
1492	if (skb_is_gso(skb))
1493		return true;
1494
1495	return false;
1496}
 
1497
1498/**
1499 * dev_forward_skb - loopback an skb to another netif
1500 *
1501 * @dev: destination network device
1502 * @skb: buffer to forward
1503 *
1504 * return values:
1505 *	NET_RX_SUCCESS	(no congestion)
1506 *	NET_RX_DROP     (packet was dropped, but freed)
1507 *
1508 * dev_forward_skb can be used for injecting an skb from the
1509 * start_xmit function of one device into the receive queue
1510 * of another device.
1511 *
1512 * The receiving device may be in another namespace, so
1513 * we have to clear all information in the skb that could
1514 * impact namespace isolation.
1515 */
1516int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
1517{
1518	if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
1519		if (skb_copy_ubufs(skb, GFP_ATOMIC)) {
1520			atomic_long_inc(&dev->rx_dropped);
1521			kfree_skb(skb);
1522			return NET_RX_DROP;
1523		}
1524	}
1525
1526	skb_orphan(skb);
1527	nf_reset(skb);
1528
1529	if (unlikely(!is_skb_forwardable(dev, skb))) {
1530		atomic_long_inc(&dev->rx_dropped);
1531		kfree_skb(skb);
1532		return NET_RX_DROP;
1533	}
1534	skb_set_dev(skb, dev);
1535	skb->tstamp.tv64 = 0;
1536	skb->pkt_type = PACKET_HOST;
1537	skb->protocol = eth_type_trans(skb, dev);
1538	return netif_rx(skb);
1539}
1540EXPORT_SYMBOL_GPL(dev_forward_skb);
1541
1542static inline int deliver_skb(struct sk_buff *skb,
1543			      struct packet_type *pt_prev,
1544			      struct net_device *orig_dev)
1545{
1546	atomic_inc(&skb->users);
 
 
1547	return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
1548}
1549
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1550/*
1551 *	Support routine. Sends outgoing frames to any network
1552 *	taps currently in use.
1553 */
1554
1555static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
1556{
1557	struct packet_type *ptype;
 
1558	struct sk_buff *skb2 = NULL;
1559	struct packet_type *pt_prev = NULL;
1560
1561	rcu_read_lock();
1562	list_for_each_entry_rcu(ptype, &ptype_all, list) {
 
 
 
 
1563		/* Never send packets back to the socket
1564		 * they originated from - MvS (miquels@drinkel.ow.org)
1565		 */
1566		if ((ptype->dev == dev || !ptype->dev) &&
1567		    (ptype->af_packet_priv == NULL ||
1568		     (struct sock *)ptype->af_packet_priv != skb->sk)) {
1569			if (pt_prev) {
1570				deliver_skb(skb2, pt_prev, skb->dev);
1571				pt_prev = ptype;
1572				continue;
1573			}
1574
1575			skb2 = skb_clone(skb, GFP_ATOMIC);
1576			if (!skb2)
1577				break;
 
 
1578
1579			net_timestamp_set(skb2);
 
 
 
 
 
 
 
 
 
 
 
1580
1581			/* skb->nh should be correctly
1582			   set by sender, so that the second statement is
1583			   just protection against buggy protocols.
1584			 */
1585			skb_reset_mac_header(skb2);
 
 
1586
1587			if (skb_network_header(skb2) < skb2->data ||
1588			    skb2->network_header > skb2->tail) {
1589				if (net_ratelimit())
1590					printk(KERN_CRIT "protocol %04x is "
1591					       "buggy, dev %s\n",
1592					       ntohs(skb2->protocol),
1593					       dev->name);
1594				skb_reset_network_header(skb2);
1595			}
1596
1597			skb2->transport_header = skb2->network_header;
1598			skb2->pkt_type = PACKET_OUTGOING;
1599			pt_prev = ptype;
1600		}
 
 
 
 
 
 
1601	}
1602	if (pt_prev)
1603		pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
1604	rcu_read_unlock();
1605}
 
1606
1607/* netif_setup_tc - Handle tc mappings on real_num_tx_queues change
 
1608 * @dev: Network device
1609 * @txq: number of queues available
1610 *
1611 * If real_num_tx_queues is changed the tc mappings may no longer be
1612 * valid. To resolve this verify the tc mapping remains valid and if
1613 * not NULL the mapping. With no priorities mapping to this
1614 * offset/count pair it will no longer be used. In the worst case TC0
1615 * is invalid nothing can be done so disable priority mappings. If is
1616 * expected that drivers will fix this mapping if they can before
1617 * calling netif_set_real_num_tx_queues.
1618 */
1619static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1620{
1621	int i;
1622	struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
1623
1624	/* If TC0 is invalidated disable TC mapping */
1625	if (tc->offset + tc->count > txq) {
1626		pr_warning("Number of in use tx queues changed "
1627			   "invalidating tc mappings. Priority "
1628			   "traffic classification disabled!\n");
1629		dev->num_tc = 0;
1630		return;
1631	}
1632
1633	/* Invalidated prio to tc mappings set to TC0 */
1634	for (i = 1; i < TC_BITMASK + 1; i++) {
1635		int q = netdev_get_prio_tc_map(dev, i);
1636
1637		tc = &dev->tc_to_txq[q];
1638		if (tc->offset + tc->count > txq) {
1639			pr_warning("Number of in use tx queues "
1640				   "changed. Priority %i to tc "
1641				   "mapping %i is no longer valid "
1642				   "setting map to 0\n",
1643				   i, q);
1644			netdev_set_prio_tc_map(dev, i, 0);
1645		}
1646	}
1647}
1648
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1649/*
1650 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
1651 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
1652 */
1653int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
1654{
 
1655	int rc;
1656
 
 
1657	if (txq < 1 || txq > dev->num_tx_queues)
1658		return -EINVAL;
1659
1660	if (dev->reg_state == NETREG_REGISTERED ||
1661	    dev->reg_state == NETREG_UNREGISTERING) {
1662		ASSERT_RTNL();
1663
1664		rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
1665						  txq);
1666		if (rc)
1667			return rc;
1668
1669		if (dev->num_tc)
1670			netif_setup_tc(dev, txq);
1671
1672		if (txq < dev->real_num_tx_queues)
 
 
 
 
 
 
 
1673			qdisc_reset_all_tx_gt(dev, txq);
 
 
 
 
 
 
1674	}
1675
1676	dev->real_num_tx_queues = txq;
1677	return 0;
1678}
1679EXPORT_SYMBOL(netif_set_real_num_tx_queues);
1680
1681#ifdef CONFIG_RPS
1682/**
1683 *	netif_set_real_num_rx_queues - set actual number of RX queues used
1684 *	@dev: Network device
1685 *	@rxq: Actual number of RX queues
1686 *
1687 *	This must be called either with the rtnl_lock held or before
1688 *	registration of the net device.  Returns 0 on success, or a
1689 *	negative error code.  If called before registration, it always
1690 *	succeeds.
1691 */
1692int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
1693{
1694	int rc;
1695
1696	if (rxq < 1 || rxq > dev->num_rx_queues)
1697		return -EINVAL;
1698
1699	if (dev->reg_state == NETREG_REGISTERED) {
1700		ASSERT_RTNL();
1701
1702		rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
1703						  rxq);
1704		if (rc)
1705			return rc;
1706	}
1707
1708	dev->real_num_rx_queues = rxq;
1709	return 0;
1710}
1711EXPORT_SYMBOL(netif_set_real_num_rx_queues);
1712#endif
1713
1714static inline void __netif_reschedule(struct Qdisc *q)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1715{
1716	struct softnet_data *sd;
1717	unsigned long flags;
1718
1719	local_irq_save(flags);
1720	sd = &__get_cpu_var(softnet_data);
1721	q->next_sched = NULL;
1722	*sd->output_queue_tailp = q;
1723	sd->output_queue_tailp = &q->next_sched;
1724	raise_softirq_irqoff(NET_TX_SOFTIRQ);
1725	local_irq_restore(flags);
1726}
1727
1728void __netif_schedule(struct Qdisc *q)
1729{
1730	if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
1731		__netif_reschedule(q);
1732}
1733EXPORT_SYMBOL(__netif_schedule);
1734
1735void dev_kfree_skb_irq(struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
1736{
1737	if (atomic_dec_and_test(&skb->users)) {
1738		struct softnet_data *sd;
1739		unsigned long flags;
1740
1741		local_irq_save(flags);
1742		sd = &__get_cpu_var(softnet_data);
1743		skb->next = sd->completion_queue;
1744		sd->completion_queue = skb;
1745		raise_softirq_irqoff(NET_TX_SOFTIRQ);
1746		local_irq_restore(flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1747	}
 
 
 
 
 
 
1748}
1749EXPORT_SYMBOL(dev_kfree_skb_irq);
1750
1751void dev_kfree_skb_any(struct sk_buff *skb)
1752{
1753	if (in_irq() || irqs_disabled())
1754		dev_kfree_skb_irq(skb);
1755	else
1756		dev_kfree_skb(skb);
1757}
1758EXPORT_SYMBOL(dev_kfree_skb_any);
1759
1760
1761/**
1762 * netif_device_detach - mark device as removed
1763 * @dev: network device
1764 *
1765 * Mark device as removed from system and therefore no longer available.
1766 */
1767void netif_device_detach(struct net_device *dev)
1768{
1769	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
1770	    netif_running(dev)) {
1771		netif_tx_stop_all_queues(dev);
1772	}
1773}
1774EXPORT_SYMBOL(netif_device_detach);
1775
1776/**
1777 * netif_device_attach - mark device as attached
1778 * @dev: network device
1779 *
1780 * Mark device as attached from system and restart if needed.
1781 */
1782void netif_device_attach(struct net_device *dev)
1783{
1784	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
1785	    netif_running(dev)) {
1786		netif_tx_wake_all_queues(dev);
1787		__netdev_watchdog_up(dev);
1788	}
1789}
1790EXPORT_SYMBOL(netif_device_attach);
1791
1792/**
1793 * skb_dev_set -- assign a new device to a buffer
1794 * @skb: buffer for the new device
1795 * @dev: network device
1796 *
1797 * If an skb is owned by a device already, we have to reset
1798 * all data private to the namespace a device belongs to
1799 * before assigning it a new device.
1800 */
1801#ifdef CONFIG_NET_NS
1802void skb_set_dev(struct sk_buff *skb, struct net_device *dev)
1803{
1804	skb_dst_drop(skb);
1805	if (skb->dev && !net_eq(dev_net(skb->dev), dev_net(dev))) {
1806		secpath_reset(skb);
1807		nf_reset(skb);
1808		skb_init_secmark(skb);
1809		skb->mark = 0;
1810		skb->priority = 0;
1811		skb->nf_trace = 0;
1812		skb->ipvs_property = 0;
1813#ifdef CONFIG_NET_SCHED
1814		skb->tc_index = 0;
1815#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1816	}
1817	skb->dev = dev;
 
 
 
1818}
1819EXPORT_SYMBOL(skb_set_dev);
1820#endif /* CONFIG_NET_NS */
1821
1822/*
1823 * Invalidate hardware checksum when packet is to be mangled, and
1824 * complete checksum manually on outgoing path.
1825 */
1826int skb_checksum_help(struct sk_buff *skb)
1827{
1828	__wsum csum;
1829	int ret = 0, offset;
1830
1831	if (skb->ip_summed == CHECKSUM_COMPLETE)
1832		goto out_set_summed;
1833
1834	if (unlikely(skb_shinfo(skb)->gso_size)) {
1835		/* Let GSO fix up the checksum. */
1836		goto out_set_summed;
 
 
 
 
 
 
 
 
 
 
 
 
 
1837	}
1838
1839	offset = skb_checksum_start_offset(skb);
1840	BUG_ON(offset >= skb_headlen(skb));
 
 
 
 
 
 
1841	csum = skb_checksum(skb, offset, skb->len - offset, 0);
1842
1843	offset += skb->csum_offset;
1844	BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
1845
1846	if (skb_cloned(skb) &&
1847	    !skb_clone_writable(skb, offset + sizeof(__sum16))) {
1848		ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
1849		if (ret)
1850			goto out;
1851	}
 
 
 
1852
1853	*(__sum16 *)(skb->data + offset) = csum_fold(csum);
1854out_set_summed:
1855	skb->ip_summed = CHECKSUM_NONE;
1856out:
1857	return ret;
1858}
1859EXPORT_SYMBOL(skb_checksum_help);
1860
1861/**
1862 *	skb_gso_segment - Perform segmentation on skb.
1863 *	@skb: buffer to segment
1864 *	@features: features for the output path (see dev->features)
1865 *
1866 *	This function segments the given skb and returns a list of segments.
1867 *
1868 *	It may return NULL if the skb requires no segmentation.  This is
1869 *	only possible when GSO is used for verifying header integrity.
1870 */
1871struct sk_buff *skb_gso_segment(struct sk_buff *skb, u32 features)
1872{
1873	struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
1874	struct packet_type *ptype;
1875	__be16 type = skb->protocol;
1876	int vlan_depth = ETH_HLEN;
1877	int err;
1878
1879	while (type == htons(ETH_P_8021Q)) {
1880		struct vlan_hdr *vh;
1881
1882		if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
1883			return ERR_PTR(-EINVAL);
1884
1885		vh = (struct vlan_hdr *)(skb->data + vlan_depth);
1886		type = vh->h_vlan_encapsulated_proto;
1887		vlan_depth += VLAN_HLEN;
 
 
 
 
 
 
 
 
 
 
1888	}
1889
1890	skb_reset_mac_header(skb);
1891	skb->mac_len = skb->network_header - skb->mac_header;
1892	__skb_pull(skb, skb->mac_len);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1893
1894	if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
1895		struct net_device *dev = skb->dev;
1896		struct ethtool_drvinfo info = {};
1897
1898		if (dev && dev->ethtool_ops && dev->ethtool_ops->get_drvinfo)
1899			dev->ethtool_ops->get_drvinfo(dev, &info);
1900
1901		WARN(1, "%s: caps=(0x%lx, 0x%lx) len=%d data_len=%d ip_summed=%d\n",
1902		     info.driver, dev ? dev->features : 0L,
1903		     skb->sk ? skb->sk->sk_route_caps : 0L,
1904		     skb->len, skb->data_len, skb->ip_summed);
1905
1906		if (skb_header_cloned(skb) &&
1907		    (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
1908			return ERR_PTR(err);
1909	}
1910
1911	rcu_read_lock();
1912	list_for_each_entry_rcu(ptype,
1913			&ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
1914		if (ptype->type == type && !ptype->dev && ptype->gso_segment) {
1915			if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
1916				err = ptype->gso_send_check(skb);
1917				segs = ERR_PTR(err);
1918				if (err || skb_gso_ok(skb, features))
1919					break;
1920				__skb_push(skb, (skb->data -
1921						 skb_network_header(skb)));
1922			}
1923			segs = ptype->gso_segment(skb, features);
1924			break;
1925		}
1926	}
1927	rcu_read_unlock();
1928
1929	__skb_push(skb, skb->data - skb_mac_header(skb));
 
1930
1931	return segs;
1932}
1933EXPORT_SYMBOL(skb_gso_segment);
1934
1935/* Take action when hardware reception checksum errors are detected. */
1936#ifdef CONFIG_BUG
1937void netdev_rx_csum_fault(struct net_device *dev)
 
 
 
 
 
 
 
1938{
1939	if (net_ratelimit()) {
1940		printk(KERN_ERR "%s: hw csum failure.\n",
1941			dev ? dev->name : "<unknown>");
1942		dump_stack();
1943	}
1944}
1945EXPORT_SYMBOL(netdev_rx_csum_fault);
1946#endif
1947
1948/* Actually, we should eliminate this check as soon as we know, that:
1949 * 1. IOMMU is present and allows to map all the memory.
1950 * 2. No high memory really exists on this machine.
1951 */
1952
1953static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
1954{
1955#ifdef CONFIG_HIGHMEM
1956	int i;
 
1957	if (!(dev->features & NETIF_F_HIGHDMA)) {
1958		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
1959			if (PageHighMem(skb_shinfo(skb)->frags[i].page))
1960				return 1;
1961	}
1962
1963	if (PCI_DMA_BUS_IS_PHYS) {
1964		struct device *pdev = dev->dev.parent;
1965
1966		if (!pdev)
1967			return 0;
1968		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1969			dma_addr_t addr = page_to_phys(skb_shinfo(skb)->frags[i].page);
1970			if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
1971				return 1;
1972		}
1973	}
1974#endif
1975	return 0;
1976}
1977
1978struct dev_gso_cb {
1979	void (*destructor)(struct sk_buff *skb);
1980};
 
 
 
 
 
 
 
1981
1982#define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)
 
 
 
 
 
 
 
 
 
1983
1984static void dev_gso_skb_destructor(struct sk_buff *skb)
 
1985{
1986	struct dev_gso_cb *cb;
1987
1988	do {
1989		struct sk_buff *nskb = skb->next;
1990
1991		skb->next = nskb->next;
1992		nskb->next = NULL;
1993		kfree_skb(nskb);
1994	} while (skb->next);
 
 
1995
1996	cb = DEV_GSO_CB(skb);
1997	if (cb->destructor)
1998		cb->destructor(skb);
1999}
2000
2001/**
2002 *	dev_gso_segment - Perform emulated hardware segmentation on skb.
2003 *	@skb: buffer to segment
2004 *	@features: device features as applicable to this skb
2005 *
2006 *	This function segments the given skb and stores the list of segments
2007 *	in skb->next.
2008 */
2009static int dev_gso_segment(struct sk_buff *skb, int features)
 
 
2010{
2011	struct sk_buff *segs;
 
2012
2013	segs = skb_gso_segment(skb, features);
 
 
 
 
2014
2015	/* Verifying header integrity only. */
2016	if (!segs)
2017		return 0;
2018
2019	if (IS_ERR(segs))
2020		return PTR_ERR(segs);
2021
2022	skb->next = segs;
2023	DEV_GSO_CB(skb)->destructor = skb->destructor;
2024	skb->destructor = dev_gso_skb_destructor;
 
2025
2026	return 0;
2027}
 
 
 
 
 
 
2028
2029/*
2030 * Try to orphan skb early, right before transmission by the device.
2031 * We cannot orphan skb if tx timestamp is requested or the sk-reference
2032 * is needed on driver level for other reasons, e.g. see net/can/raw.c
2033 */
2034static inline void skb_orphan_try(struct sk_buff *skb)
2035{
2036	struct sock *sk = skb->sk;
2037
2038	if (sk && !skb_shinfo(skb)->tx_flags) {
2039		/* skb_tx_hash() wont be able to get sk.
2040		 * We copy sk_hash into skb->rxhash
2041		 */
2042		if (!skb->rxhash)
2043			skb->rxhash = sk->sk_hash;
2044		skb_orphan(skb);
2045	}
 
 
2046}
2047
2048static bool can_checksum_protocol(unsigned long features, __be16 protocol)
2049{
2050	return ((features & NETIF_F_GEN_CSUM) ||
2051		((features & NETIF_F_V4_CSUM) &&
2052		 protocol == htons(ETH_P_IP)) ||
2053		((features & NETIF_F_V6_CSUM) &&
2054		 protocol == htons(ETH_P_IPV6)) ||
2055		((features & NETIF_F_FCOE_CRC) &&
2056		 protocol == htons(ETH_P_FCOE)));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2057}
 
2058
2059static u32 harmonize_features(struct sk_buff *skb, __be16 protocol, u32 features)
 
2060{
2061	if (!can_checksum_protocol(features, protocol)) {
2062		features &= ~NETIF_F_ALL_CSUM;
2063		features &= ~NETIF_F_SG;
2064	} else if (illegal_highdma(skb->dev, skb)) {
2065		features &= ~NETIF_F_SG;
2066	}
 
 
 
 
2067
2068	return features;
2069}
2070
2071u32 netif_skb_features(struct sk_buff *skb)
 
2072{
2073	__be16 protocol = skb->protocol;
2074	u32 features = skb->dev->features;
2075
2076	if (protocol == htons(ETH_P_8021Q)) {
2077		struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
2078		protocol = veh->h_vlan_encapsulated_proto;
2079	} else if (!vlan_tx_tag_present(skb)) {
2080		return harmonize_features(skb, protocol, features);
2081	}
2082
2083	features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_TX);
 
 
 
 
 
2084
2085	if (protocol != htons(ETH_P_8021Q)) {
2086		return harmonize_features(skb, protocol, features);
2087	} else {
2088		features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
2089				NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_TX;
2090		return harmonize_features(skb, protocol, features);
2091	}
 
 
 
 
2092}
2093EXPORT_SYMBOL(netif_skb_features);
2094
2095/*
2096 * Returns true if either:
2097 *	1. skb has frag_list and the device doesn't support FRAGLIST, or
2098 *	2. skb is fragmented and the device does not support SG, or if
2099 *	   at least one of fragments is in highmem and device does not
2100 *	   support DMA from it.
2101 */
2102static inline int skb_needs_linearize(struct sk_buff *skb,
2103				      int features)
2104{
2105	return skb_is_nonlinear(skb) &&
2106			((skb_has_frag_list(skb) &&
2107				!(features & NETIF_F_FRAGLIST)) ||
2108			(skb_shinfo(skb)->nr_frags &&
2109				!(features & NETIF_F_SG)));
2110}
2111
2112int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
2113			struct netdev_queue *txq)
2114{
2115	const struct net_device_ops *ops = dev->netdev_ops;
2116	int rc = NETDEV_TX_OK;
2117	unsigned int skb_len;
2118
2119	if (likely(!skb->next)) {
2120		u32 features;
2121
2122		/*
2123		 * If device doesn't need skb->dst, release it right now while
2124		 * its hot in this cpu cache
2125		 */
2126		if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2127			skb_dst_drop(skb);
 
 
 
 
 
 
 
 
 
 
 
2128
2129		if (!list_empty(&ptype_all))
2130			dev_queue_xmit_nit(skb, dev);
 
2131
2132		skb_orphan_try(skb);
 
 
 
2133
2134		features = netif_skb_features(skb);
 
 
2135
2136		if (vlan_tx_tag_present(skb) &&
2137		    !(features & NETIF_F_HW_VLAN_TX)) {
2138			skb = __vlan_put_tag(skb, vlan_tx_tag_get(skb));
2139			if (unlikely(!skb))
2140				goto out;
2141
2142			skb->vlan_tci = 0;
 
 
 
 
 
2143		}
2144
2145		if (netif_needs_gso(skb, features)) {
2146			if (unlikely(dev_gso_segment(skb, features)))
2147				goto out_kfree_skb;
2148			if (skb->next)
2149				goto gso;
2150		} else {
2151			if (skb_needs_linearize(skb, features) &&
2152			    __skb_linearize(skb))
 
 
 
 
 
 
 
 
2153				goto out_kfree_skb;
2154
2155			/* If packet is not checksummed and device does not
2156			 * support checksumming for this protocol, complete
2157			 * checksumming here.
2158			 */
2159			if (skb->ip_summed == CHECKSUM_PARTIAL) {
2160				skb_set_transport_header(skb,
2161					skb_checksum_start_offset(skb));
2162				if (!(features & NETIF_F_ALL_CSUM) &&
2163				     skb_checksum_help(skb))
2164					goto out_kfree_skb;
2165			}
2166		}
2167
2168		skb_len = skb->len;
2169		rc = ops->ndo_start_xmit(skb, dev);
2170		trace_net_dev_xmit(skb, rc, dev, skb_len);
2171		if (rc == NETDEV_TX_OK)
2172			txq_trans_update(txq);
2173		return rc;
2174	}
2175
2176gso:
2177	do {
2178		struct sk_buff *nskb = skb->next;
2179
2180		skb->next = nskb->next;
2181		nskb->next = NULL;
2182
2183		/*
2184		 * If device doesn't need nskb->dst, release it right now while
2185		 * its hot in this cpu cache
2186		 */
2187		if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
2188			skb_dst_drop(nskb);
2189
2190		skb_len = nskb->len;
2191		rc = ops->ndo_start_xmit(nskb, dev);
2192		trace_net_dev_xmit(nskb, rc, dev, skb_len);
2193		if (unlikely(rc != NETDEV_TX_OK)) {
2194			if (rc & ~NETDEV_TX_MASK)
2195				goto out_kfree_gso_skb;
2196			nskb->next = skb->next;
2197			skb->next = nskb;
2198			return rc;
2199		}
2200		txq_trans_update(txq);
2201		if (unlikely(netif_tx_queue_stopped(txq) && skb->next))
2202			return NETDEV_TX_BUSY;
2203	} while (skb->next);
2204
2205out_kfree_gso_skb:
2206	if (likely(skb->next == NULL))
2207		skb->destructor = DEV_GSO_CB(skb)->destructor;
2208out_kfree_skb:
2209	kfree_skb(skb);
2210out:
2211	return rc;
 
2212}
2213
2214static u32 hashrnd __read_mostly;
2215
2216/*
2217 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
2218 * to be used as a distribution range.
2219 */
2220u16 __skb_tx_hash(const struct net_device *dev, const struct sk_buff *skb,
2221		  unsigned int num_tx_queues)
2222{
2223	u32 hash;
2224	u16 qoffset = 0;
2225	u16 qcount = num_tx_queues;
2226
2227	if (skb_rx_queue_recorded(skb)) {
2228		hash = skb_get_rx_queue(skb);
2229		while (unlikely(hash >= num_tx_queues))
2230			hash -= num_tx_queues;
2231		return hash;
2232	}
2233
2234	if (dev->num_tc) {
2235		u8 tc = netdev_get_prio_tc_map(dev, skb->priority);
2236		qoffset = dev->tc_to_txq[tc].offset;
2237		qcount = dev->tc_to_txq[tc].count;
2238	}
2239
2240	if (skb->sk && skb->sk->sk_hash)
2241		hash = skb->sk->sk_hash;
2242	else
2243		hash = (__force u16) skb->protocol ^ skb->rxhash;
2244	hash = jhash_1word(hash, hashrnd);
2245
2246	return (u16) (((u64) hash * qcount) >> 32) + qoffset;
2247}
2248EXPORT_SYMBOL(__skb_tx_hash);
2249
2250static inline u16 dev_cap_txqueue(struct net_device *dev, u16 queue_index)
2251{
2252	if (unlikely(queue_index >= dev->real_num_tx_queues)) {
2253		if (net_ratelimit()) {
2254			pr_warning("%s selects TX queue %d, but "
2255				"real number of TX queues is %d\n",
2256				dev->name, queue_index, dev->real_num_tx_queues);
2257		}
2258		return 0;
2259	}
2260	return queue_index;
2261}
 
2262
2263static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb)
2264{
2265#ifdef CONFIG_XPS
2266	struct xps_dev_maps *dev_maps;
2267	struct xps_map *map;
2268	int queue_index = -1;
 
 
 
 
 
 
2269
2270	rcu_read_lock();
2271	dev_maps = rcu_dereference(dev->xps_maps);
2272	if (dev_maps) {
2273		map = rcu_dereference(
2274		    dev_maps->cpu_map[raw_smp_processor_id()]);
2275		if (map) {
2276			if (map->len == 1)
2277				queue_index = map->queues[0];
2278			else {
2279				u32 hash;
2280				if (skb->sk && skb->sk->sk_hash)
2281					hash = skb->sk->sk_hash;
2282				else
2283					hash = (__force u16) skb->protocol ^
2284					    skb->rxhash;
2285				hash = jhash_1word(hash, hashrnd);
2286				queue_index = map->queues[
2287				    ((u64)hash * map->len) >> 32];
2288			}
2289			if (unlikely(queue_index >= dev->real_num_tx_queues))
2290				queue_index = -1;
2291		}
2292	}
2293	rcu_read_unlock();
2294
2295	return queue_index;
2296#else
2297	return -1;
2298#endif
2299}
2300
2301static struct netdev_queue *dev_pick_tx(struct net_device *dev,
2302					struct sk_buff *skb)
2303{
2304	int queue_index;
2305	const struct net_device_ops *ops = dev->netdev_ops;
 
2306
2307	if (dev->real_num_tx_queues == 1)
2308		queue_index = 0;
2309	else if (ops->ndo_select_queue) {
2310		queue_index = ops->ndo_select_queue(dev, skb);
2311		queue_index = dev_cap_txqueue(dev, queue_index);
2312	} else {
2313		struct sock *sk = skb->sk;
2314		queue_index = sk_tx_queue_get(sk);
2315
2316		if (queue_index < 0 || skb->ooo_okay ||
2317		    queue_index >= dev->real_num_tx_queues) {
2318			int old_index = queue_index;
2319
2320			queue_index = get_xps_queue(dev, skb);
2321			if (queue_index < 0)
2322				queue_index = skb_tx_hash(dev, skb);
2323
2324			if (queue_index != old_index && sk) {
2325				struct dst_entry *dst =
2326				    rcu_dereference_check(sk->sk_dst_cache, 1);
2327
2328				if (dst && skb_dst(skb) == dst)
2329					sk_tx_queue_set(sk, queue_index);
2330			}
 
2331		}
 
2332	}
 
2333
2334	skb_set_queue_mapping(skb, queue_index);
2335	return netdev_get_tx_queue(dev, queue_index);
 
 
 
 
 
 
 
 
2336}
2337
2338static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
2339				 struct net_device *dev,
2340				 struct netdev_queue *txq)
2341{
2342	spinlock_t *root_lock = qdisc_lock(q);
 
2343	bool contended;
2344	int rc;
2345
2346	qdisc_skb_cb(skb)->pkt_len = skb->len;
2347	qdisc_calculate_pkt_len(skb, q);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2348	/*
2349	 * Heuristic to force contended enqueues to serialize on a
2350	 * separate lock before trying to get qdisc main lock.
2351	 * This permits __QDISC_STATE_RUNNING owner to get the lock more often
2352	 * and dequeue packets faster.
 
 
 
 
2353	 */
2354	contended = qdisc_is_running(q);
2355	if (unlikely(contended))
2356		spin_lock(&q->busylock);
2357
2358	spin_lock(root_lock);
2359	if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
2360		kfree_skb(skb);
2361		rc = NET_XMIT_DROP;
2362	} else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2363		   qdisc_run_begin(q)) {
2364		/*
2365		 * This is a work-conserving queue; there are no old skbs
2366		 * waiting to be sent out; and the qdisc is not running -
2367		 * xmit the skb directly.
2368		 */
2369		if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE))
2370			skb_dst_force(skb);
2371
2372		qdisc_bstats_update(q, skb);
2373
2374		if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
2375			if (unlikely(contended)) {
2376				spin_unlock(&q->busylock);
2377				contended = false;
2378			}
2379			__qdisc_run(q);
2380		} else
2381			qdisc_run_end(q);
2382
 
2383		rc = NET_XMIT_SUCCESS;
2384	} else {
2385		skb_dst_force(skb);
2386		rc = q->enqueue(skb, q) & NET_XMIT_MASK;
 
2387		if (qdisc_run_begin(q)) {
2388			if (unlikely(contended)) {
2389				spin_unlock(&q->busylock);
2390				contended = false;
2391			}
2392			__qdisc_run(q);
 
2393		}
2394	}
2395	spin_unlock(root_lock);
 
 
 
2396	if (unlikely(contended))
2397		spin_unlock(&q->busylock);
2398	return rc;
2399}
2400
2401static DEFINE_PER_CPU(int, xmit_recursion);
2402#define RECURSION_LIMIT 10
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2403
2404/**
2405 *	dev_queue_xmit - transmit a buffer
 
 
2406 *	@skb: buffer to transmit
2407 *
2408 *	Queue a buffer for transmission to a network device. The caller must
2409 *	have set the device and priority and built the buffer before calling
2410 *	this function. The function can be called from an interrupt.
2411 *
2412 *	A negative errno code is returned on a failure. A success does not
2413 *	guarantee the frame will be transmitted as it may be dropped due
2414 *	to congestion or traffic shaping.
2415 *
2416 * -----------------------------------------------------------------------------------
2417 *      I notice this method can also return errors from the queue disciplines,
2418 *      including NET_XMIT_DROP, which is a positive value.  So, errors can also
2419 *      be positive.
2420 *
2421 *      Regardless of the return value, the skb is consumed, so it is currently
2422 *      difficult to retry a send to this method.  (You can bump the ref count
2423 *      before sending to hold a reference for retry if you are careful.)
2424 *
2425 *      When calling this method, interrupts MUST be enabled.  This is because
2426 *      the BH enable code must have IRQs enabled so that it will not deadlock.
2427 *          --BLG
2428 */
2429int dev_queue_xmit(struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2430{
2431	struct net_device *dev = skb->dev;
2432	struct netdev_queue *txq;
2433	struct Qdisc *q;
2434	int rc = -ENOMEM;
 
 
 
 
 
 
 
2435
2436	/* Disable soft irqs for various locks below. Also
2437	 * stops preemption for RCU.
2438	 */
2439	rcu_read_lock_bh();
2440
2441	txq = dev_pick_tx(dev, skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2442	q = rcu_dereference_bh(txq->qdisc);
2443
2444#ifdef CONFIG_NET_CLS_ACT
2445	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
2446#endif
2447	trace_net_dev_queue(skb);
2448	if (q->enqueue) {
2449		rc = __dev_xmit_skb(skb, q, dev, txq);
2450		goto out;
2451	}
2452
2453	/* The device has no queue. Common case for software devices:
2454	   loopback, all the sorts of tunnels...
2455
2456	   Really, it is unlikely that netif_tx_lock protection is necessary
2457	   here.  (f.e. loopback and IP tunnels are clean ignoring statistics
2458	   counters.)
2459	   However, it is possible, that they rely on protection
2460	   made by us here.
2461
2462	   Check this and shot the lock. It is not prone from deadlocks.
2463	   Either shot noqueue qdisc, it is even simpler 8)
2464	 */
2465	if (dev->flags & IFF_UP) {
2466		int cpu = smp_processor_id(); /* ok because BHs are off */
2467
2468		if (txq->xmit_lock_owner != cpu) {
 
 
 
 
 
2469
2470			if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
2471				goto recursion_alert;
 
2472
2473			HARD_TX_LOCK(dev, txq, cpu);
2474
2475			if (!netif_tx_queue_stopped(txq)) {
2476				__this_cpu_inc(xmit_recursion);
2477				rc = dev_hard_start_xmit(skb, dev, txq);
2478				__this_cpu_dec(xmit_recursion);
2479				if (dev_xmit_complete(rc)) {
2480					HARD_TX_UNLOCK(dev, txq);
2481					goto out;
2482				}
2483			}
2484			HARD_TX_UNLOCK(dev, txq);
2485			if (net_ratelimit())
2486				printk(KERN_CRIT "Virtual device %s asks to "
2487				       "queue packet!\n", dev->name);
2488		} else {
2489			/* Recursion is detected! It is possible,
2490			 * unfortunately
2491			 */
2492recursion_alert:
2493			if (net_ratelimit())
2494				printk(KERN_CRIT "Dead loop on virtual device "
2495				       "%s, fix it urgently!\n", dev->name);
2496		}
2497	}
2498
2499	rc = -ENETDOWN;
2500	rcu_read_unlock_bh();
2501
2502	kfree_skb(skb);
 
2503	return rc;
2504out:
2505	rcu_read_unlock_bh();
2506	return rc;
2507}
2508EXPORT_SYMBOL(dev_queue_xmit);
2509
 
 
 
 
 
 
 
2510
2511/*=======================================================================
2512			Receiver routines
2513  =======================================================================*/
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2514
2515int netdev_max_backlog __read_mostly = 1000;
2516int netdev_tstamp_prequeue __read_mostly = 1;
2517int netdev_budget __read_mostly = 300;
2518int weight_p __read_mostly = 64;            /* old backlog weight */
 
 
 
 
 
 
 
 
 
 
 
 
 
2519
2520/* Called with irq disabled */
2521static inline void ____napi_schedule(struct softnet_data *sd,
2522				     struct napi_struct *napi)
2523{
2524	list_add_tail(&napi->poll_list, &sd->poll_list);
2525	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
2526}
2527
2528/*
2529 * __skb_get_rxhash: calculate a flow hash based on src/dst addresses
2530 * and src/dst port numbers. Returns a non-zero hash number on success
2531 * and 0 on failure.
2532 */
2533__u32 __skb_get_rxhash(struct sk_buff *skb)
2534{
2535	int nhoff, hash = 0, poff;
2536	const struct ipv6hdr *ip6;
2537	const struct iphdr *ip;
2538	u8 ip_proto;
2539	u32 addr1, addr2, ihl;
2540	union {
2541		u32 v32;
2542		u16 v16[2];
2543	} ports;
2544
2545	nhoff = skb_network_offset(skb);
2546
2547	switch (skb->protocol) {
2548	case __constant_htons(ETH_P_IP):
2549		if (!pskb_may_pull(skb, sizeof(*ip) + nhoff))
2550			goto done;
2551
2552		ip = (const struct iphdr *) (skb->data + nhoff);
2553		if (ip_is_fragment(ip))
2554			ip_proto = 0;
2555		else
2556			ip_proto = ip->protocol;
2557		addr1 = (__force u32) ip->saddr;
2558		addr2 = (__force u32) ip->daddr;
2559		ihl = ip->ihl;
2560		break;
2561	case __constant_htons(ETH_P_IPV6):
2562		if (!pskb_may_pull(skb, sizeof(*ip6) + nhoff))
2563			goto done;
2564
2565		ip6 = (const struct ipv6hdr *) (skb->data + nhoff);
2566		ip_proto = ip6->nexthdr;
2567		addr1 = (__force u32) ip6->saddr.s6_addr32[3];
2568		addr2 = (__force u32) ip6->daddr.s6_addr32[3];
2569		ihl = (40 >> 2);
2570		break;
2571	default:
2572		goto done;
2573	}
2574
2575	ports.v32 = 0;
2576	poff = proto_ports_offset(ip_proto);
2577	if (poff >= 0) {
2578		nhoff += ihl * 4 + poff;
2579		if (pskb_may_pull(skb, nhoff + 4)) {
2580			ports.v32 = * (__force u32 *) (skb->data + nhoff);
2581			if (ports.v16[1] < ports.v16[0])
2582				swap(ports.v16[0], ports.v16[1]);
2583		}
2584	}
2585
2586	/* get a consistent hash (same value on both flow directions) */
2587	if (addr2 < addr1)
2588		swap(addr1, addr2);
2589
2590	hash = jhash_3words(addr1, addr2, ports.v32, hashrnd);
2591	if (!hash)
2592		hash = 1;
2593
2594done:
2595	return hash;
2596}
2597EXPORT_SYMBOL(__skb_get_rxhash);
2598
2599#ifdef CONFIG_RPS
2600
2601/* One global table that all flow-based protocols share. */
2602struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2603EXPORT_SYMBOL(rps_sock_flow_table);
 
2604
2605static struct rps_dev_flow *
2606set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2607	    struct rps_dev_flow *rflow, u16 next_cpu)
2608{
2609	u16 tcpu;
2610
2611	tcpu = rflow->cpu = next_cpu;
2612	if (tcpu != RPS_NO_CPU) {
2613#ifdef CONFIG_RFS_ACCEL
2614		struct netdev_rx_queue *rxqueue;
2615		struct rps_dev_flow_table *flow_table;
2616		struct rps_dev_flow *old_rflow;
 
2617		u32 flow_id;
2618		u16 rxq_index;
2619		int rc;
2620
2621		/* Should we steer this flow to a different hardware queue? */
2622		if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
2623		    !(dev->features & NETIF_F_NTUPLE))
2624			goto out;
2625		rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
2626		if (rxq_index == skb_get_rx_queue(skb))
2627			goto out;
2628
2629		rxqueue = dev->_rx + rxq_index;
2630		flow_table = rcu_dereference(rxqueue->rps_flow_table);
2631		if (!flow_table)
2632			goto out;
2633		flow_id = skb->rxhash & flow_table->mask;
2634		rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
2635							rxq_index, flow_id);
2636		if (rc < 0)
2637			goto out;
2638		old_rflow = rflow;
2639		rflow = &flow_table->flows[flow_id];
2640		rflow->cpu = next_cpu;
2641		rflow->filter = rc;
2642		if (old_rflow->filter == rflow->filter)
2643			old_rflow->filter = RPS_NO_FILTER;
2644	out:
2645#endif
2646		rflow->last_qtail =
2647			per_cpu(softnet_data, tcpu).input_queue_head;
2648	}
2649
 
2650	return rflow;
2651}
2652
2653/*
2654 * get_rps_cpu is called from netif_receive_skb and returns the target
2655 * CPU from the RPS map of the receiving queue for a given skb.
2656 * rcu_read_lock must be held on entry.
2657 */
2658static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
2659		       struct rps_dev_flow **rflowp)
2660{
2661	struct netdev_rx_queue *rxqueue;
 
 
2662	struct rps_map *map;
2663	struct rps_dev_flow_table *flow_table;
2664	struct rps_sock_flow_table *sock_flow_table;
2665	int cpu = -1;
2666	u16 tcpu;
 
2667
2668	if (skb_rx_queue_recorded(skb)) {
2669		u16 index = skb_get_rx_queue(skb);
 
2670		if (unlikely(index >= dev->real_num_rx_queues)) {
2671			WARN_ONCE(dev->real_num_rx_queues > 1,
2672				  "%s received packet on queue %u, but number "
2673				  "of RX queues is %u\n",
2674				  dev->name, index, dev->real_num_rx_queues);
2675			goto done;
2676		}
2677		rxqueue = dev->_rx + index;
2678	} else
2679		rxqueue = dev->_rx;
 
2680
 
2681	map = rcu_dereference(rxqueue->rps_map);
2682	if (map) {
2683		if (map->len == 1 &&
2684		    !rcu_dereference_raw(rxqueue->rps_flow_table)) {
2685			tcpu = map->cpus[0];
2686			if (cpu_online(tcpu))
2687				cpu = tcpu;
2688			goto done;
2689		}
2690	} else if (!rcu_dereference_raw(rxqueue->rps_flow_table)) {
2691		goto done;
2692	}
2693
2694	skb_reset_network_header(skb);
2695	if (!skb_get_rxhash(skb))
 
2696		goto done;
2697
2698	flow_table = rcu_dereference(rxqueue->rps_flow_table);
2699	sock_flow_table = rcu_dereference(rps_sock_flow_table);
2700	if (flow_table && sock_flow_table) {
2701		u16 next_cpu;
2702		struct rps_dev_flow *rflow;
 
 
 
 
 
 
 
 
 
 
 
2703
2704		rflow = &flow_table->flows[skb->rxhash & flow_table->mask];
 
 
 
2705		tcpu = rflow->cpu;
2706
2707		next_cpu = sock_flow_table->ents[skb->rxhash &
2708		    sock_flow_table->mask];
2709
2710		/*
2711		 * If the desired CPU (where last recvmsg was done) is
2712		 * different from current CPU (one in the rx-queue flow
2713		 * table entry), switch if one of the following holds:
2714		 *   - Current CPU is unset (equal to RPS_NO_CPU).
2715		 *   - Current CPU is offline.
2716		 *   - The current CPU's queue tail has advanced beyond the
2717		 *     last packet that was enqueued using this table entry.
2718		 *     This guarantees that all previous packets for the flow
2719		 *     have been dequeued, thus preserving in order delivery.
2720		 */
2721		if (unlikely(tcpu != next_cpu) &&
2722		    (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
2723		     ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
2724		      rflow->last_qtail)) >= 0))
 
2725			rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
 
2726
2727		if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
2728			*rflowp = rflow;
2729			cpu = tcpu;
2730			goto done;
2731		}
2732	}
2733
 
 
2734	if (map) {
2735		tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32];
2736
2737		if (cpu_online(tcpu)) {
2738			cpu = tcpu;
2739			goto done;
2740		}
2741	}
2742
2743done:
2744	return cpu;
2745}
2746
2747#ifdef CONFIG_RFS_ACCEL
2748
2749/**
2750 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
2751 * @dev: Device on which the filter was set
2752 * @rxq_index: RX queue index
2753 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
2754 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
2755 *
2756 * Drivers that implement ndo_rx_flow_steer() should periodically call
2757 * this function for each installed filter and remove the filters for
2758 * which it returns %true.
2759 */
2760bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
2761			 u32 flow_id, u16 filter_id)
2762{
2763	struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
2764	struct rps_dev_flow_table *flow_table;
2765	struct rps_dev_flow *rflow;
2766	bool expire = true;
2767	int cpu;
2768
2769	rcu_read_lock();
2770	flow_table = rcu_dereference(rxqueue->rps_flow_table);
2771	if (flow_table && flow_id <= flow_table->mask) {
2772		rflow = &flow_table->flows[flow_id];
2773		cpu = ACCESS_ONCE(rflow->cpu);
2774		if (rflow->filter == filter_id && cpu != RPS_NO_CPU &&
2775		    ((int)(per_cpu(softnet_data, cpu).input_queue_head -
2776			   rflow->last_qtail) <
2777		     (int)(10 * flow_table->mask)))
2778			expire = false;
2779	}
2780	rcu_read_unlock();
2781	return expire;
2782}
2783EXPORT_SYMBOL(rps_may_expire_flow);
2784
2785#endif /* CONFIG_RFS_ACCEL */
2786
2787/* Called from hardirq (IPI) context */
2788static void rps_trigger_softirq(void *data)
2789{
2790	struct softnet_data *sd = data;
2791
2792	____napi_schedule(sd, &sd->backlog);
2793	sd->received_rps++;
2794}
2795
2796#endif /* CONFIG_RPS */
2797
 
 
 
 
 
 
 
 
 
2798/*
2799 * Check if this softnet_data structure is another cpu one
2800 * If yes, queue it to our IPI list and return 1
2801 * If no, return 0
 
 
 
 
 
2802 */
2803static int rps_ipi_queued(struct softnet_data *sd)
2804{
 
 
2805#ifdef CONFIG_RPS
2806	struct softnet_data *mysd = &__get_cpu_var(softnet_data);
 
 
 
 
2807
2808	if (sd != mysd) {
2809		sd->rps_ipi_next = mysd->rps_ipi_list;
2810		mysd->rps_ipi_list = sd;
2811
2812		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
2813		return 1;
 
 
 
 
2814	}
2815#endif /* CONFIG_RPS */
2816	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2817}
2818
2819/*
2820 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
2821 * queue (may be a remote CPU queue).
2822 */
2823static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
2824			      unsigned int *qtail)
2825{
 
2826	struct softnet_data *sd;
2827	unsigned long flags;
 
 
 
 
 
 
 
2828
 
2829	sd = &per_cpu(softnet_data, cpu);
2830
2831	local_irq_save(flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2832
2833	rps_lock(sd);
2834	if (skb_queue_len(&sd->input_pkt_queue) <= netdev_max_backlog) {
2835		if (skb_queue_len(&sd->input_pkt_queue)) {
2836enqueue:
2837			__skb_queue_tail(&sd->input_pkt_queue, skb);
2838			input_queue_tail_incr_save(sd, qtail);
2839			rps_unlock(sd);
2840			local_irq_restore(flags);
2841			return NET_RX_SUCCESS;
2842		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2843
2844		/* Schedule NAPI for backlog device
2845		 * We can use non atomic operation since we own the queue lock
2846		 */
2847		if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
2848			if (!rps_ipi_queued(sd))
2849				____napi_schedule(sd, &sd->backlog);
2850		}
2851		goto enqueue;
 
 
 
 
 
 
 
 
 
2852	}
2853
2854	sd->dropped++;
2855	rps_unlock(sd);
2856
2857	local_irq_restore(flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2858
2859	atomic_long_inc(&skb->dev->rx_dropped);
2860	kfree_skb(skb);
2861	return NET_RX_DROP;
2862}
2863
2864/**
2865 *	netif_rx	-	post buffer to the network code
2866 *	@skb: buffer to post
2867 *
2868 *	This function receives a packet from a device driver and queues it for
2869 *	the upper (protocol) levels to process.  It always succeeds. The buffer
2870 *	may be dropped during processing for congestion control or by the
2871 *	protocol layers.
2872 *
2873 *	return values:
2874 *	NET_RX_SUCCESS	(no congestion)
2875 *	NET_RX_DROP     (packet was dropped)
2876 *
2877 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2878
2879int netif_rx(struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2880{
2881	int ret;
2882
2883	/* if netpoll wants it, pretend we never saw it */
2884	if (netpoll_rx(skb))
2885		return NET_RX_DROP;
2886
2887	if (netdev_tstamp_prequeue)
2888		net_timestamp_check(skb);
2889
2890	trace_netif_rx(skb);
2891#ifdef CONFIG_RPS
2892	{
2893		struct rps_dev_flow voidflow, *rflow = &voidflow;
2894		int cpu;
2895
2896		preempt_disable();
2897		rcu_read_lock();
2898
2899		cpu = get_rps_cpu(skb->dev, skb, &rflow);
2900		if (cpu < 0)
2901			cpu = smp_processor_id();
2902
2903		ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
2904
2905		rcu_read_unlock();
2906		preempt_enable();
2907	}
2908#else
2909	{
2910		unsigned int qtail;
2911		ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
2912		put_cpu();
2913	}
2914#endif
2915	return ret;
2916}
2917EXPORT_SYMBOL(netif_rx);
2918
2919int netif_rx_ni(struct sk_buff *skb)
 
 
 
 
 
 
 
 
2920{
2921	int err;
 
 
2922
2923	preempt_disable();
2924	err = netif_rx(skb);
2925	if (local_softirq_pending())
2926		do_softirq();
2927	preempt_enable();
 
2928
2929	return err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2930}
2931EXPORT_SYMBOL(netif_rx_ni);
2932
2933static void net_tx_action(struct softirq_action *h)
2934{
2935	struct softnet_data *sd = &__get_cpu_var(softnet_data);
2936
2937	if (sd->completion_queue) {
2938		struct sk_buff *clist;
2939
2940		local_irq_disable();
2941		clist = sd->completion_queue;
2942		sd->completion_queue = NULL;
2943		local_irq_enable();
2944
2945		while (clist) {
2946			struct sk_buff *skb = clist;
 
2947			clist = clist->next;
2948
2949			WARN_ON(atomic_read(&skb->users));
2950			trace_kfree_skb(skb, net_tx_action);
2951			__kfree_skb(skb);
 
 
 
 
 
 
 
 
 
2952		}
2953	}
2954
2955	if (sd->output_queue) {
2956		struct Qdisc *head;
2957
2958		local_irq_disable();
2959		head = sd->output_queue;
2960		sd->output_queue = NULL;
2961		sd->output_queue_tailp = &sd->output_queue;
2962		local_irq_enable();
2963
 
 
2964		while (head) {
2965			struct Qdisc *q = head;
2966			spinlock_t *root_lock;
2967
2968			head = head->next_sched;
2969
2970			root_lock = qdisc_lock(q);
2971			if (spin_trylock(root_lock)) {
2972				smp_mb__before_clear_bit();
2973				clear_bit(__QDISC_STATE_SCHED,
2974					  &q->state);
2975				qdisc_run(q);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2976				spin_unlock(root_lock);
2977			} else {
2978				if (!test_bit(__QDISC_STATE_DEACTIVATED,
2979					      &q->state)) {
2980					__netif_reschedule(q);
2981				} else {
2982					smp_mb__before_clear_bit();
2983					clear_bit(__QDISC_STATE_SCHED,
2984						  &q->state);
2985				}
2986			}
2987		}
 
 
2988	}
 
 
2989}
2990
2991#if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
2992    (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
2993/* This hook is defined here for ATM LANE */
2994int (*br_fdb_test_addr_hook)(struct net_device *dev,
2995			     unsigned char *addr) __read_mostly;
2996EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
2997#endif
2998
2999#ifdef CONFIG_NET_CLS_ACT
3000/* TODO: Maybe we should just force sch_ingress to be compiled in
3001 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
3002 * a compare and 2 stores extra right now if we dont have it on
3003 * but have CONFIG_NET_CLS_ACT
3004 * NOTE: This doesn't stop any functionality; if you dont have
3005 * the ingress scheduler, you just can't add policies on ingress.
3006 *
 
3007 */
3008static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
3009{
3010	struct net_device *dev = skb->dev;
3011	u32 ttl = G_TC_RTTL(skb->tc_verd);
3012	int result = TC_ACT_OK;
3013	struct Qdisc *q;
3014
3015	if (unlikely(MAX_RED_LOOP < ttl++)) {
3016		if (net_ratelimit())
3017			pr_warning( "Redir loop detected Dropping packet (%d->%d)\n",
3018			       skb->skb_iif, dev->ifindex);
3019		return TC_ACT_SHOT;
3020	}
3021
3022	skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
3023	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3024
3025	q = rxq->qdisc;
3026	if (q != &noop_qdisc) {
3027		spin_lock(qdisc_lock(q));
3028		if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
3029			result = qdisc_enqueue_root(skb, q);
3030		spin_unlock(qdisc_lock(q));
3031	}
3032
3033	return result;
3034}
3035
3036static inline struct sk_buff *handle_ing(struct sk_buff *skb,
3037					 struct packet_type **pt_prev,
3038					 int *ret, struct net_device *orig_dev)
3039{
3040	struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
3041
3042	if (!rxq || rxq->qdisc == &noop_qdisc)
3043		goto out;
3044
3045	if (*pt_prev) {
3046		*ret = deliver_skb(skb, *pt_prev, orig_dev);
3047		*pt_prev = NULL;
3048	}
3049
3050	switch (ing_filter(skb, rxq)) {
3051	case TC_ACT_SHOT:
3052	case TC_ACT_STOLEN:
3053		kfree_skb(skb);
3054		return NULL;
3055	}
3056
3057out:
3058	skb->tc_verd = 0;
3059	return skb;
3060}
3061#endif
3062
3063/**
3064 *	netdev_rx_handler_register - register receive handler
3065 *	@dev: device to register a handler for
3066 *	@rx_handler: receive handler to register
3067 *	@rx_handler_data: data pointer that is used by rx handler
3068 *
3069 *	Register a receive hander for a device. This handler will then be
3070 *	called from __netif_receive_skb. A negative errno code is returned
3071 *	on a failure.
3072 *
3073 *	The caller must hold the rtnl_mutex.
3074 *
3075 *	For a general description of rx_handler, see enum rx_handler_result.
3076 */
3077int netdev_rx_handler_register(struct net_device *dev,
3078			       rx_handler_func_t *rx_handler,
3079			       void *rx_handler_data)
3080{
3081	ASSERT_RTNL();
 
3082
3083	if (dev->rx_handler)
3084		return -EBUSY;
3085
 
3086	rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3087	rcu_assign_pointer(dev->rx_handler, rx_handler);
3088
3089	return 0;
3090}
3091EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
3092
3093/**
3094 *	netdev_rx_handler_unregister - unregister receive handler
3095 *	@dev: device to unregister a handler from
3096 *
3097 *	Unregister a receive hander from a device.
3098 *
3099 *	The caller must hold the rtnl_mutex.
3100 */
3101void netdev_rx_handler_unregister(struct net_device *dev)
3102{
3103
3104	ASSERT_RTNL();
3105	rcu_assign_pointer(dev->rx_handler, NULL);
3106	rcu_assign_pointer(dev->rx_handler_data, NULL);
 
 
 
 
 
3107}
3108EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
3109
3110static int __netif_receive_skb(struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3111{
3112	struct packet_type *ptype, *pt_prev;
3113	rx_handler_func_t *rx_handler;
 
3114	struct net_device *orig_dev;
3115	struct net_device *null_or_dev;
3116	bool deliver_exact = false;
3117	int ret = NET_RX_DROP;
3118	__be16 type;
3119
3120	if (!netdev_tstamp_prequeue)
3121		net_timestamp_check(skb);
3122
3123	trace_netif_receive_skb(skb);
3124
3125	/* if we've gotten here through NAPI, check netpoll */
3126	if (netpoll_receive_skb(skb))
3127		return NET_RX_DROP;
3128
3129	if (!skb->skb_iif)
3130		skb->skb_iif = skb->dev->ifindex;
3131	orig_dev = skb->dev;
3132
3133	skb_reset_network_header(skb);
3134	skb_reset_transport_header(skb);
 
3135	skb_reset_mac_len(skb);
3136
3137	pt_prev = NULL;
3138
3139	rcu_read_lock();
3140
3141another_round:
 
3142
3143	__this_cpu_inc(softnet_data.processed);
3144
3145	if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) {
3146		skb = vlan_untag(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3147		if (unlikely(!skb))
3148			goto out;
3149	}
3150
3151#ifdef CONFIG_NET_CLS_ACT
3152	if (skb->tc_verd & TC_NCLS) {
3153		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
3154		goto ncls;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3155	}
3156#endif
 
 
 
 
3157
3158	list_for_each_entry_rcu(ptype, &ptype_all, list) {
3159		if (!ptype->dev || ptype->dev == skb->dev) {
3160			if (pt_prev)
3161				ret = deliver_skb(skb, pt_prev, orig_dev);
3162			pt_prev = ptype;
3163		}
 
 
 
 
3164	}
3165
3166#ifdef CONFIG_NET_CLS_ACT
3167	skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
3168	if (!skb)
3169		goto out;
3170ncls:
3171#endif
3172
3173	rx_handler = rcu_dereference(skb->dev->rx_handler);
3174	if (rx_handler) {
3175		if (pt_prev) {
3176			ret = deliver_skb(skb, pt_prev, orig_dev);
3177			pt_prev = NULL;
3178		}
3179		switch (rx_handler(&skb)) {
3180		case RX_HANDLER_CONSUMED:
 
3181			goto out;
3182		case RX_HANDLER_ANOTHER:
3183			goto another_round;
3184		case RX_HANDLER_EXACT:
3185			deliver_exact = true;
 
3186		case RX_HANDLER_PASS:
3187			break;
3188		default:
3189			BUG();
3190		}
3191	}
3192
3193	if (vlan_tx_tag_present(skb)) {
3194		if (pt_prev) {
3195			ret = deliver_skb(skb, pt_prev, orig_dev);
3196			pt_prev = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3197		}
3198		if (vlan_do_receive(&skb)) {
3199			ret = __netif_receive_skb(skb);
3200			goto out;
3201		} else if (unlikely(!skb))
3202			goto out;
3203	}
3204
 
 
3205	/* deliver only exact match when indicated */
3206	null_or_dev = deliver_exact ? skb->dev : NULL;
 
 
 
 
3207
3208	type = skb->protocol;
3209	list_for_each_entry_rcu(ptype,
3210			&ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3211		if (ptype->type == type &&
3212		    (ptype->dev == null_or_dev || ptype->dev == skb->dev ||
3213		     ptype->dev == orig_dev)) {
3214			if (pt_prev)
3215				ret = deliver_skb(skb, pt_prev, orig_dev);
3216			pt_prev = ptype;
3217		}
3218	}
3219
3220	if (pt_prev) {
3221		ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
 
 
3222	} else {
3223		atomic_long_inc(&skb->dev->rx_dropped);
3224		kfree_skb(skb);
 
 
 
 
3225		/* Jamal, now you will not able to escape explaining
3226		 * me how you were going to use this. :-)
3227		 */
3228		ret = NET_RX_DROP;
3229	}
3230
3231out:
3232	rcu_read_unlock();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3233	return ret;
3234}
3235
3236/**
3237 *	netif_receive_skb - process receive buffer from network
3238 *	@skb: buffer to process
3239 *
3240 *	netif_receive_skb() is the main receive data processing function.
3241 *	It always succeeds. The buffer may be dropped during processing
3242 *	for congestion control or by the protocol layers.
3243 *
3244 *	This function may only be called from softirq context and interrupts
3245 *	should be enabled.
3246 *
3247 *	Return values (usually ignored):
3248 *	NET_RX_SUCCESS: no congestion
3249 *	NET_RX_DROP: packet was dropped
3250 */
3251int netif_receive_skb(struct sk_buff *skb)
3252{
3253	if (netdev_tstamp_prequeue)
3254		net_timestamp_check(skb);
3255
3256	if (skb_defer_rx_timestamp(skb))
3257		return NET_RX_SUCCESS;
 
3258
3259#ifdef CONFIG_RPS
3260	{
3261		struct rps_dev_flow voidflow, *rflow = &voidflow;
3262		int cpu, ret;
3263
3264		rcu_read_lock();
 
 
 
 
3265
3266		cpu = get_rps_cpu(skb->dev, skb, &rflow);
3267
3268		if (cpu >= 0) {
3269			ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
3270			rcu_read_unlock();
3271		} else {
3272			rcu_read_unlock();
3273			ret = __netif_receive_skb(skb);
 
 
 
3274		}
3275
3276		return ret;
3277	}
3278#else
3279	return __netif_receive_skb(skb);
3280#endif
3281}
3282EXPORT_SYMBOL(netif_receive_skb);
3283
3284/* Network device is going away, flush any packets still pending
3285 * Called with irqs disabled.
3286 */
3287static void flush_backlog(void *arg)
3288{
3289	struct net_device *dev = arg;
3290	struct softnet_data *sd = &__get_cpu_var(softnet_data);
3291	struct sk_buff *skb, *tmp;
 
 
 
 
 
 
 
 
 
3292
3293	rps_lock(sd);
3294	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3295		if (skb->dev == dev) {
3296			__skb_unlink(skb, &sd->input_pkt_queue);
3297			kfree_skb(skb);
3298			input_queue_head_incr(sd);
 
 
 
 
 
 
 
 
 
3299		}
 
3300	}
3301	rps_unlock(sd);
3302
3303	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
3304		if (skb->dev == dev) {
3305			__skb_unlink(skb, &sd->process_queue);
3306			kfree_skb(skb);
3307			input_queue_head_incr(sd);
3308		}
3309	}
3310}
3311
3312static int napi_gro_complete(struct sk_buff *skb)
3313{
3314	struct packet_type *ptype;
3315	__be16 type = skb->protocol;
3316	struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK];
3317	int err = -ENOENT;
3318
3319	if (NAPI_GRO_CB(skb)->count == 1) {
3320		skb_shinfo(skb)->gso_size = 0;
3321		goto out;
3322	}
3323
3324	rcu_read_lock();
3325	list_for_each_entry_rcu(ptype, head, list) {
3326		if (ptype->type != type || ptype->dev || !ptype->gro_complete)
3327			continue;
 
 
 
 
 
 
 
 
 
 
3328
3329		err = ptype->gro_complete(skb);
3330		break;
3331	}
3332	rcu_read_unlock();
3333
3334	if (err) {
3335		WARN_ON(&ptype->list == head);
3336		kfree_skb(skb);
3337		return NET_RX_SUCCESS;
3338	}
3339
3340out:
3341	return netif_receive_skb(skb);
3342}
3343
3344inline void napi_gro_flush(struct napi_struct *napi)
3345{
 
3346	struct sk_buff *skb, *next;
 
3347
3348	for (skb = napi->gro_list; skb; skb = next) {
3349		next = skb->next;
3350		skb->next = NULL;
3351		napi_gro_complete(skb);
 
 
 
 
 
 
 
 
 
 
 
3352	}
3353
3354	napi->gro_count = 0;
3355	napi->gro_list = NULL;
 
 
 
3356}
3357EXPORT_SYMBOL(napi_gro_flush);
3358
3359enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3360{
3361	struct sk_buff **pp = NULL;
3362	struct packet_type *ptype;
3363	__be16 type = skb->protocol;
3364	struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK];
3365	int same_flow;
3366	int mac_len;
3367	enum gro_result ret;
3368
3369	if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb))
3370		goto normal;
 
 
 
3371
3372	if (skb_is_gso(skb) || skb_has_frag_list(skb))
3373		goto normal;
 
 
 
 
 
 
3374
3375	rcu_read_lock();
3376	list_for_each_entry_rcu(ptype, head, list) {
3377		if (ptype->type != type || ptype->dev || !ptype->gro_receive)
3378			continue;
3379
3380		skb_set_network_header(skb, skb_gro_offset(skb));
3381		mac_len = skb->network_header - skb->mac_header;
3382		skb->mac_len = mac_len;
3383		NAPI_GRO_CB(skb)->same_flow = 0;
3384		NAPI_GRO_CB(skb)->flush = 0;
3385		NAPI_GRO_CB(skb)->free = 0;
3386
3387		pp = ptype->gro_receive(&napi->gro_list, skb);
3388		break;
3389	}
3390	rcu_read_unlock();
3391
3392	if (&ptype->list == head)
3393		goto normal;
3394
3395	same_flow = NAPI_GRO_CB(skb)->same_flow;
3396	ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
 
3397
3398	if (pp) {
3399		struct sk_buff *nskb = *pp;
3400
3401		*pp = nskb->next;
3402		nskb->next = NULL;
3403		napi_gro_complete(nskb);
3404		napi->gro_count--;
3405	}
3406
3407	if (same_flow)
3408		goto ok;
 
 
 
3409
3410	if (NAPI_GRO_CB(skb)->flush || napi->gro_count >= MAX_GRO_SKBS)
3411		goto normal;
3412
3413	napi->gro_count++;
3414	NAPI_GRO_CB(skb)->count = 1;
3415	skb_shinfo(skb)->gso_size = skb_gro_len(skb);
3416	skb->next = napi->gro_list;
3417	napi->gro_list = skb;
3418	ret = GRO_HELD;
3419
3420pull:
3421	if (skb_headlen(skb) < skb_gro_offset(skb)) {
3422		int grow = skb_gro_offset(skb) - skb_headlen(skb);
3423
3424		BUG_ON(skb->end - skb->tail < grow);
3425
3426		memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
3427
3428		skb->tail += grow;
3429		skb->data_len -= grow;
3430
3431		skb_shinfo(skb)->frags[0].page_offset += grow;
3432		skb_shinfo(skb)->frags[0].size -= grow;
3433
3434		if (unlikely(!skb_shinfo(skb)->frags[0].size)) {
3435			put_page(skb_shinfo(skb)->frags[0].page);
3436			memmove(skb_shinfo(skb)->frags,
3437				skb_shinfo(skb)->frags + 1,
3438				--skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
3439		}
3440	}
3441
3442ok:
 
3443	return ret;
3444
3445normal:
3446	ret = GRO_NORMAL;
3447	goto pull;
3448}
3449EXPORT_SYMBOL(dev_gro_receive);
3450
3451static inline gro_result_t
3452__napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3453{
3454	struct sk_buff *p;
 
3455
3456	for (p = napi->gro_list; p; p = p->next) {
3457		unsigned long diffs;
 
 
 
 
 
 
3458
3459		diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3460		diffs |= p->vlan_tci ^ skb->vlan_tci;
3461		diffs |= compare_ether_header(skb_mac_header(p),
3462					      skb_gro_mac_header(skb));
3463		NAPI_GRO_CB(p)->same_flow = !diffs;
3464		NAPI_GRO_CB(p)->flush = 0;
 
 
 
 
 
 
 
3465	}
3466
3467	return dev_gro_receive(napi, skb);
 
3468}
3469
3470gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3471{
3472	switch (ret) {
3473	case GRO_NORMAL:
3474		if (netif_receive_skb(skb))
3475			ret = GRO_DROP;
3476		break;
3477
3478	case GRO_DROP:
3479	case GRO_MERGED_FREE:
3480		kfree_skb(skb);
3481		break;
3482
3483	case GRO_HELD:
3484	case GRO_MERGED:
3485		break;
3486	}
3487
3488	return ret;
3489}
3490EXPORT_SYMBOL(napi_skb_finish);
3491
3492void skb_gro_reset_offset(struct sk_buff *skb)
 
 
 
 
 
 
 
 
 
 
3493{
3494	NAPI_GRO_CB(skb)->data_offset = 0;
3495	NAPI_GRO_CB(skb)->frag0 = NULL;
3496	NAPI_GRO_CB(skb)->frag0_len = 0;
3497
3498	if (skb->mac_header == skb->tail &&
3499	    !PageHighMem(skb_shinfo(skb)->frags[0].page)) {
3500		NAPI_GRO_CB(skb)->frag0 =
3501			page_address(skb_shinfo(skb)->frags[0].page) +
3502			skb_shinfo(skb)->frags[0].page_offset;
3503		NAPI_GRO_CB(skb)->frag0_len = skb_shinfo(skb)->frags[0].size;
3504	}
 
 
3505}
3506EXPORT_SYMBOL(skb_gro_reset_offset);
3507
3508gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3509{
3510	skb_gro_reset_offset(skb);
3511
3512	return napi_skb_finish(__napi_gro_receive(napi, skb), skb);
3513}
3514EXPORT_SYMBOL(napi_gro_receive);
3515
3516static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
 
3517{
3518	__skb_pull(skb, skb_headlen(skb));
3519	skb_reserve(skb, NET_IP_ALIGN - skb_headroom(skb));
3520	skb->vlan_tci = 0;
3521	skb->dev = napi->dev;
3522	skb->skb_iif = 0;
3523
3524	napi->skb = skb;
3525}
3526
3527struct sk_buff *napi_get_frags(struct napi_struct *napi)
3528{
3529	struct sk_buff *skb = napi->skb;
 
 
 
 
 
 
3530
3531	if (!skb) {
3532		skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
3533		if (skb)
3534			napi->skb = skb;
 
 
 
3535	}
3536	return skb;
 
3537}
3538EXPORT_SYMBOL(napi_get_frags);
3539
3540gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb,
3541			       gro_result_t ret)
3542{
3543	switch (ret) {
3544	case GRO_NORMAL:
3545	case GRO_HELD:
3546		skb->protocol = eth_type_trans(skb, skb->dev);
3547
3548		if (ret == GRO_HELD)
3549			skb_gro_pull(skb, -ETH_HLEN);
3550		else if (netif_receive_skb(skb))
3551			ret = GRO_DROP;
3552		break;
3553
3554	case GRO_DROP:
3555	case GRO_MERGED_FREE:
3556		napi_reuse_skb(napi, skb);
3557		break;
 
 
3558
3559	case GRO_MERGED:
3560		break;
3561	}
3562
3563	return ret;
 
 
 
3564}
3565EXPORT_SYMBOL(napi_frags_finish);
3566
3567struct sk_buff *napi_frags_skb(struct napi_struct *napi)
3568{
3569	struct sk_buff *skb = napi->skb;
3570	struct ethhdr *eth;
3571	unsigned int hlen;
3572	unsigned int off;
3573
3574	napi->skb = NULL;
 
 
 
 
3575
3576	skb_reset_mac_header(skb);
3577	skb_gro_reset_offset(skb);
3578
3579	off = skb_gro_offset(skb);
3580	hlen = off + sizeof(*eth);
3581	eth = skb_gro_header_fast(skb, off);
3582	if (skb_gro_header_hard(skb, hlen)) {
3583		eth = skb_gro_header_slow(skb, hlen, off);
3584		if (unlikely(!eth)) {
3585			napi_reuse_skb(napi, skb);
3586			skb = NULL;
3587			goto out;
3588		}
3589	}
3590
3591	skb_gro_pull(skb, sizeof(*eth));
3592
3593	/*
3594	 * This works because the only protocols we care about don't require
3595	 * special handling.  We'll fix it up properly at the end.
3596	 */
3597	skb->protocol = eth->h_proto;
 
3598
3599out:
3600	return skb;
3601}
3602EXPORT_SYMBOL(napi_frags_skb);
3603
3604gro_result_t napi_gro_frags(struct napi_struct *napi)
3605{
3606	struct sk_buff *skb = napi_frags_skb(napi);
 
 
3607
3608	if (!skb)
3609		return GRO_DROP;
3610
3611	return napi_frags_finish(napi, skb, __napi_gro_receive(napi, skb));
 
3612}
3613EXPORT_SYMBOL(napi_gro_frags);
3614
3615/*
3616 * net_rps_action sends any pending IPI's for rps.
3617 * Note: called with local irq disabled, but exits with local irq enabled.
3618 */
3619static void net_rps_action_and_irq_enable(struct softnet_data *sd)
3620{
3621#ifdef CONFIG_RPS
3622	struct softnet_data *remsd = sd->rps_ipi_list;
3623
3624	if (remsd) {
3625		sd->rps_ipi_list = NULL;
3626
3627		local_irq_enable();
3628
3629		/* Send pending IPI's to kick RPS processing on remote cpus. */
3630		while (remsd) {
3631			struct softnet_data *next = remsd->rps_ipi_next;
3632
3633			if (cpu_online(remsd->cpu))
3634				__smp_call_function_single(remsd->cpu,
3635							   &remsd->csd, 0);
3636			remsd = next;
3637		}
3638	} else
3639#endif
3640		local_irq_enable();
3641}
3642
 
 
 
 
 
 
 
 
 
3643static int process_backlog(struct napi_struct *napi, int quota)
3644{
 
 
3645	int work = 0;
3646	struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
3647
3648#ifdef CONFIG_RPS
3649	/* Check if we have pending ipi, its better to send them now,
3650	 * not waiting net_rx_action() end.
3651	 */
3652	if (sd->rps_ipi_list) {
3653		local_irq_disable();
3654		net_rps_action_and_irq_enable(sd);
3655	}
3656#endif
3657	napi->weight = weight_p;
3658	local_irq_disable();
3659	while (work < quota) {
3660		struct sk_buff *skb;
3661		unsigned int qlen;
3662
 
3663		while ((skb = __skb_dequeue(&sd->process_queue))) {
3664			local_irq_enable();
 
3665			__netif_receive_skb(skb);
3666			local_irq_disable();
3667			input_queue_head_incr(sd);
3668			if (++work >= quota) {
3669				local_irq_enable();
3670				return work;
3671			}
 
 
3672		}
 
3673
3674		rps_lock(sd);
3675		qlen = skb_queue_len(&sd->input_pkt_queue);
3676		if (qlen)
3677			skb_queue_splice_tail_init(&sd->input_pkt_queue,
3678						   &sd->process_queue);
3679
3680		if (qlen < quota - work) {
3681			/*
3682			 * Inline a custom version of __napi_complete().
3683			 * only current cpu owns and manipulates this napi,
3684			 * and NAPI_STATE_SCHED is the only possible flag set on backlog.
3685			 * we can use a plain write instead of clear_bit(),
 
3686			 * and we dont need an smp_mb() memory barrier.
3687			 */
3688			list_del(&napi->poll_list);
3689			napi->state = 0;
3690
3691			quota = work + qlen;
 
 
 
3692		}
3693		rps_unlock(sd);
3694	}
3695	local_irq_enable();
3696
 
 
3697	return work;
3698}
3699
3700/**
3701 * __napi_schedule - schedule for receive
3702 * @n: entry to schedule
3703 *
3704 * The entry's receive function will be scheduled to run
 
3705 */
3706void __napi_schedule(struct napi_struct *n)
3707{
3708	unsigned long flags;
3709
3710	local_irq_save(flags);
3711	____napi_schedule(&__get_cpu_var(softnet_data), n);
3712	local_irq_restore(flags);
3713}
3714EXPORT_SYMBOL(__napi_schedule);
3715
3716void __napi_complete(struct napi_struct *n)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3717{
3718	BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
3719	BUG_ON(n->gro_list);
3720
3721	list_del(&n->poll_list);
3722	smp_mb__before_clear_bit();
3723	clear_bit(NAPI_STATE_SCHED, &n->state);
 
3724}
3725EXPORT_SYMBOL(__napi_complete);
3726
3727void napi_complete(struct napi_struct *n)
3728{
3729	unsigned long flags;
3730
3731	/*
3732	 * don't let napi dequeue from the cpu poll list
3733	 * just in case its running on a different cpu
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3734	 */
3735	if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3736		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3737
3738	napi_gro_flush(n);
3739	local_irq_save(flags);
3740	__napi_complete(n);
3741	local_irq_restore(flags);
 
 
 
3742}
3743EXPORT_SYMBOL(napi_complete);
3744
3745void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
3746		    int (*poll)(struct napi_struct *, int), int weight)
3747{
 
 
 
3748	INIT_LIST_HEAD(&napi->poll_list);
3749	napi->gro_count = 0;
3750	napi->gro_list = NULL;
 
 
3751	napi->skb = NULL;
 
 
3752	napi->poll = poll;
 
 
 
3753	napi->weight = weight;
3754	list_add(&napi->dev_list, &dev->napi_list);
3755	napi->dev = dev;
3756#ifdef CONFIG_NETPOLL
3757	spin_lock_init(&napi->poll_lock);
3758	napi->poll_owner = -1;
3759#endif
 
3760	set_bit(NAPI_STATE_SCHED, &napi->state);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3761}
3762EXPORT_SYMBOL(netif_napi_add);
3763
3764void netif_napi_del(struct napi_struct *napi)
 
 
 
 
 
 
 
3765{
3766	struct sk_buff *skb, *next;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3767
3768	list_del_init(&napi->dev_list);
3769	napi_free_frags(napi);
3770
3771	for (skb = napi->gro_list; skb; skb = next) {
3772		next = skb->next;
3773		skb->next = NULL;
3774		kfree_skb(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3775	}
3776
3777	napi->gro_list = NULL;
3778	napi->gro_count = 0;
 
3779}
3780EXPORT_SYMBOL(netif_napi_del);
3781
3782static void net_rx_action(struct softirq_action *h)
3783{
3784	struct softnet_data *sd = &__get_cpu_var(softnet_data);
3785	unsigned long time_limit = jiffies + 2;
3786	int budget = netdev_budget;
3787	void *have;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3788
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3789	local_irq_disable();
 
 
3790
3791	while (!list_empty(&sd->poll_list)) {
3792		struct napi_struct *n;
3793		int work, weight;
3794
3795		/* If softirq window is exhuasted then punt.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3796		 * Allow this to run for 2 jiffies since which will allow
3797		 * an average latency of 1.5/HZ.
3798		 */
3799		if (unlikely(budget <= 0 || time_after(jiffies, time_limit)))
3800			goto softnet_break;
 
 
 
 
 
 
3801
3802		local_irq_enable();
 
 
 
 
 
 
3803
3804		/* Even though interrupts have been re-enabled, this
3805		 * access is safe because interrupts can only add new
3806		 * entries to the tail of this list, and only ->poll()
3807		 * calls can remove this head entry from the list.
3808		 */
3809		n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
3810
3811		have = netpoll_poll_lock(n);
 
 
3812
3813		weight = n->weight;
 
3814
3815		/* This NAPI_STATE_SCHED test is for avoiding a race
3816		 * with netpoll's poll_napi().  Only the entity which
3817		 * obtains the lock and sees NAPI_STATE_SCHED set will
3818		 * actually make the ->poll() call.  Therefore we avoid
3819		 * accidentally calling ->poll() when NAPI is not scheduled.
3820		 */
3821		work = 0;
3822		if (test_bit(NAPI_STATE_SCHED, &n->state)) {
3823			work = n->poll(n, weight);
3824			trace_napi_poll(n);
3825		}
3826
3827		WARN_ON_ONCE(work > weight);
 
3828
3829		budget -= work;
 
3830
3831		local_irq_disable();
 
 
3832
3833		/* Drivers must not modify the NAPI state if they
3834		 * consume the entire weight.  In such cases this code
3835		 * still "owns" the NAPI instance and therefore can
3836		 * move the instance around on the list at-will.
3837		 */
3838		if (unlikely(work == weight)) {
3839			if (unlikely(napi_disable_pending(n))) {
3840				local_irq_enable();
3841				napi_complete(n);
3842				local_irq_disable();
3843			} else
3844				list_move_tail(&n->poll_list, &sd->poll_list);
3845		}
3846
3847		netpoll_poll_unlock(have);
 
 
3848	}
3849out:
3850	net_rps_action_and_irq_enable(sd);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3851
3852#ifdef CONFIG_NET_DMA
3853	/*
3854	 * There may not be any more sk_buffs coming right now, so push
3855	 * any pending DMA copies to hardware
3856	 */
3857	dma_issue_pending_all();
3858#endif
 
 
3859
3860	return;
 
 
 
 
 
3861
3862softnet_break:
3863	sd->time_squeeze++;
3864	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
3865	goto out;
3866}
 
 
 
 
 
 
 
 
 
 
 
 
3867
3868static gifconf_func_t *gifconf_list[NPROTO];
 
 
3869
3870/**
3871 *	register_gifconf	-	register a SIOCGIF handler
3872 *	@family: Address family
3873 *	@gifconf: Function handler
3874 *
3875 *	Register protocol dependent address dumping routines. The handler
3876 *	that is passed must not be freed or reused until it has been replaced
3877 *	by another handler.
3878 */
3879int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
3880{
3881	if (family >= NPROTO)
3882		return -EINVAL;
3883	gifconf_list[family] = gifconf;
3884	return 0;
 
 
 
 
 
 
 
 
3885}
3886EXPORT_SYMBOL(register_gifconf);
 
 
 
 
 
 
3887
 
 
3888
3889/*
3890 *	Map an interface index to its name (SIOCGIFNAME)
 
 
 
 
 
 
 
 
 
 
 
3891 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3892
3893/*
3894 *	We need this ioctl for efficient implementation of the
3895 *	if_indextoname() function required by the IPv6 API.  Without
3896 *	it, we would have to search all the interfaces to find a
3897 *	match.  --pb
 
 
3898 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3899
3900static int dev_ifname(struct net *net, struct ifreq __user *arg)
 
 
 
 
 
 
 
 
 
 
 
3901{
3902	struct net_device *dev;
3903	struct ifreq ifr;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3904
3905	/*
3906	 *	Fetch the caller's info block.
3907	 */
 
 
 
3908
3909	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
3910		return -EFAULT;
 
 
 
 
3911
3912	rcu_read_lock();
3913	dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex);
3914	if (!dev) {
3915		rcu_read_unlock();
3916		return -ENODEV;
3917	}
3918
3919	strcpy(ifr.ifr_name, dev->name);
3920	rcu_read_unlock();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3921
3922	if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
3923		return -EFAULT;
3924	return 0;
3925}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3926
3927/*
3928 *	Perform a SIOCGIFCONF call. This structure will change
3929 *	size eventually, and there is nothing I can do about it.
3930 *	Thus we will need a 'compatibility mode'.
 
 
 
 
 
 
3931 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3932
3933static int dev_ifconf(struct net *net, char __user *arg)
 
3934{
3935	struct ifconf ifc;
3936	struct net_device *dev;
3937	char __user *pos;
3938	int len;
3939	int total;
3940	int i;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3941
3942	/*
3943	 *	Fetch the caller's info block.
3944	 */
3945
3946	if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
3947		return -EFAULT;
 
 
 
 
3948
3949	pos = ifc.ifc_buf;
3950	len = ifc.ifc_len;
 
 
 
3951
3952	/*
3953	 *	Loop over the interfaces, and write an info block for each.
3954	 */
 
 
 
3955
3956	total = 0;
3957	for_each_netdev(net, dev) {
3958		for (i = 0; i < NPROTO; i++) {
3959			if (gifconf_list[i]) {
3960				int done;
3961				if (!pos)
3962					done = gifconf_list[i](dev, NULL, 0);
3963				else
3964					done = gifconf_list[i](dev, pos + total,
3965							       len - total);
3966				if (done < 0)
3967					return -EFAULT;
3968				total += done;
3969			}
3970		}
 
 
 
3971	}
3972
3973	/*
3974	 *	All done.  Write the updated control block back to the caller.
3975	 */
3976	ifc.ifc_len = total;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3977
3978	/*
3979	 * 	Both BSD and Solaris return 0 here, so we do too.
3980	 */
3981	return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
3982}
3983
3984#ifdef CONFIG_PROC_FS
3985/*
3986 *	This is invoked by the /proc filesystem handler to display a device
3987 *	in detail.
3988 */
3989void *dev_seq_start(struct seq_file *seq, loff_t *pos)
3990	__acquires(RCU)
3991{
3992	struct net *net = seq_file_net(seq);
3993	loff_t off;
3994	struct net_device *dev;
 
 
 
 
 
 
 
 
3995
3996	rcu_read_lock();
3997	if (!*pos)
3998		return SEQ_START_TOKEN;
 
 
 
3999
4000	off = 1;
4001	for_each_netdev_rcu(net, dev)
4002		if (off++ == *pos)
4003			return dev;
 
 
 
 
 
4004
4005	return NULL;
4006}
4007
4008void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4009{
4010	struct net_device *dev = v;
 
 
 
4011
4012	if (v == SEQ_START_TOKEN)
4013		dev = first_net_device_rcu(seq_file_net(seq));
4014	else
4015		dev = next_net_device_rcu(dev);
 
 
 
 
 
 
 
 
4016
4017	++*pos;
4018	return dev;
 
 
 
4019}
4020
4021void dev_seq_stop(struct seq_file *seq, void *v)
4022	__releases(RCU)
 
 
4023{
4024	rcu_read_unlock();
 
4025}
 
4026
4027static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev)
 
4028{
4029	struct rtnl_link_stats64 temp;
4030	const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp);
 
 
 
 
 
 
 
 
 
 
 
4031
4032	seq_printf(seq, "%6s: %7llu %7llu %4llu %4llu %4llu %5llu %10llu %9llu "
4033		   "%8llu %7llu %4llu %4llu %4llu %5llu %7llu %10llu\n",
4034		   dev->name, stats->rx_bytes, stats->rx_packets,
4035		   stats->rx_errors,
4036		   stats->rx_dropped + stats->rx_missed_errors,
4037		   stats->rx_fifo_errors,
4038		   stats->rx_length_errors + stats->rx_over_errors +
4039		    stats->rx_crc_errors + stats->rx_frame_errors,
4040		   stats->rx_compressed, stats->multicast,
4041		   stats->tx_bytes, stats->tx_packets,
4042		   stats->tx_errors, stats->tx_dropped,
4043		   stats->tx_fifo_errors, stats->collisions,
4044		   stats->tx_carrier_errors +
4045		    stats->tx_aborted_errors +
4046		    stats->tx_window_errors +
4047		    stats->tx_heartbeat_errors,
4048		   stats->tx_compressed);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4049}
 
4050
4051/*
4052 *	Called from the PROCfs module. This now uses the new arbitrary sized
4053 *	/proc/net interface to create /proc/net/dev
 
 
 
 
 
4054 */
4055static int dev_seq_show(struct seq_file *seq, void *v)
4056{
4057	if (v == SEQ_START_TOKEN)
4058		seq_puts(seq, "Inter-|   Receive                            "
4059			      "                    |  Transmit\n"
4060			      " face |bytes    packets errs drop fifo frame "
4061			      "compressed multicast|bytes    packets errs "
4062			      "drop fifo colls carrier compressed\n");
4063	else
4064		dev_seq_printf_stats(seq, v);
4065	return 0;
4066}
 
4067
4068static struct softnet_data *softnet_get_online(loff_t *pos)
 
 
 
 
 
 
 
4069{
4070	struct softnet_data *sd = NULL;
4071
4072	while (*pos < nr_cpu_ids)
4073		if (cpu_online(*pos)) {
4074			sd = &per_cpu(softnet_data, *pos);
4075			break;
4076		} else
4077			++*pos;
4078	return sd;
4079}
 
4080
4081static void *softnet_seq_start(struct seq_file *seq, loff_t *pos)
 
 
4082{
4083	return softnet_get_online(pos);
 
 
 
 
 
4084}
 
 
 
 
 
4085
4086static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 
 
 
 
 
 
 
4087{
4088	++*pos;
4089	return softnet_get_online(pos);
 
4090}
4091
4092static void softnet_seq_stop(struct seq_file *seq, void *v)
 
 
 
4093{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4094}
4095
4096static int softnet_seq_show(struct seq_file *seq, void *v)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4097{
4098	struct softnet_data *sd = v;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4099
4100	seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x %08x\n",
4101		   sd->processed, sd->dropped, sd->time_squeeze, 0,
4102		   0, 0, 0, 0, /* was fastroute */
4103		   sd->cpu_collision, sd->received_rps);
4104	return 0;
 
 
 
 
 
4105}
4106
4107static const struct seq_operations dev_seq_ops = {
4108	.start = dev_seq_start,
4109	.next  = dev_seq_next,
4110	.stop  = dev_seq_stop,
4111	.show  = dev_seq_show,
4112};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4113
4114static int dev_seq_open(struct inode *inode, struct file *file)
 
 
 
 
 
 
 
 
 
4115{
4116	return seq_open_net(inode, file, &dev_seq_ops,
4117			    sizeof(struct seq_net_private));
 
 
 
 
4118}
 
4119
4120static const struct file_operations dev_seq_fops = {
4121	.owner	 = THIS_MODULE,
4122	.open    = dev_seq_open,
4123	.read    = seq_read,
4124	.llseek  = seq_lseek,
4125	.release = seq_release_net,
4126};
 
 
4127
4128static const struct seq_operations softnet_seq_ops = {
4129	.start = softnet_seq_start,
4130	.next  = softnet_seq_next,
4131	.stop  = softnet_seq_stop,
4132	.show  = softnet_seq_show,
4133};
4134
4135static int softnet_seq_open(struct inode *inode, struct file *file)
 
4136{
4137	return seq_open(file, &softnet_seq_ops);
4138}
4139
4140static const struct file_operations softnet_seq_fops = {
4141	.owner	 = THIS_MODULE,
4142	.open    = softnet_seq_open,
4143	.read    = seq_read,
4144	.llseek  = seq_lseek,
4145	.release = seq_release,
4146};
4147
4148static void *ptype_get_idx(loff_t pos)
 
 
 
4149{
4150	struct packet_type *pt = NULL;
4151	loff_t i = 0;
4152	int t;
4153
4154	list_for_each_entry_rcu(pt, &ptype_all, list) {
4155		if (i == pos)
4156			return pt;
4157		++i;
4158	}
4159
4160	for (t = 0; t < PTYPE_HASH_SIZE; t++) {
4161		list_for_each_entry_rcu(pt, &ptype_base[t], list) {
4162			if (i == pos)
4163				return pt;
4164			++i;
4165		}
 
4166	}
4167	return NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4168}
 
4169
4170static void *ptype_seq_start(struct seq_file *seq, loff_t *pos)
4171	__acquires(RCU)
4172{
4173	rcu_read_lock();
4174	return *pos ? ptype_get_idx(*pos - 1) : SEQ_START_TOKEN;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4175}
4176
4177static void *ptype_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 
 
4178{
4179	struct packet_type *pt;
4180	struct list_head *nxt;
4181	int hash;
4182
4183	++*pos;
4184	if (v == SEQ_START_TOKEN)
4185		return ptype_get_idx(0);
4186
4187	pt = v;
4188	nxt = pt->list.next;
4189	if (pt->type == htons(ETH_P_ALL)) {
4190		if (nxt != &ptype_all)
4191			goto found;
4192		hash = 0;
4193		nxt = ptype_base[0].next;
4194	} else
4195		hash = ntohs(pt->type) & PTYPE_HASH_MASK;
4196
4197	while (nxt == &ptype_base[hash]) {
4198		if (++hash >= PTYPE_HASH_SIZE)
4199			return NULL;
4200		nxt = ptype_base[hash].next;
4201	}
4202found:
4203	return list_entry(nxt, struct packet_type, list);
 
4204}
 
4205
4206static void ptype_seq_stop(struct seq_file *seq, void *v)
4207	__releases(RCU)
4208{
4209	rcu_read_unlock();
 
 
 
 
 
 
 
 
4210}
4211
4212static int ptype_seq_show(struct seq_file *seq, void *v)
 
4213{
4214	struct packet_type *pt = v;
4215
4216	if (v == SEQ_START_TOKEN)
4217		seq_puts(seq, "Type Device      Function\n");
4218	else if (pt->dev == NULL || dev_net(pt->dev) == seq_file_net(seq)) {
4219		if (pt->type == htons(ETH_P_ALL))
4220			seq_puts(seq, "ALL ");
4221		else
4222			seq_printf(seq, "%04x", ntohs(pt->type));
4223
4224		seq_printf(seq, " %-8s %pF\n",
4225			   pt->dev ? pt->dev->name : "", pt->func);
 
 
4226	}
4227
4228	return 0;
 
 
 
 
 
 
 
4229}
4230
4231static const struct seq_operations ptype_seq_ops = {
4232	.start = ptype_seq_start,
4233	.next  = ptype_seq_next,
4234	.stop  = ptype_seq_stop,
4235	.show  = ptype_seq_show,
4236};
 
 
 
 
 
 
4237
4238static int ptype_seq_open(struct inode *inode, struct file *file)
 
4239{
4240	return seq_open_net(inode, file, &ptype_seq_ops,
4241			sizeof(struct seq_net_private));
 
4242}
 
 
 
 
 
4243
4244static const struct file_operations ptype_seq_fops = {
4245	.owner	 = THIS_MODULE,
4246	.open    = ptype_seq_open,
4247	.read    = seq_read,
4248	.llseek  = seq_lseek,
4249	.release = seq_release_net,
4250};
4251
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4252
4253static int __net_init dev_proc_net_init(struct net *net)
 
 
 
 
 
 
 
 
 
 
4254{
4255	int rc = -ENOMEM;
 
 
 
 
 
 
 
 
 
4256
4257	if (!proc_net_fops_create(net, "dev", S_IRUGO, &dev_seq_fops))
4258		goto out;
4259	if (!proc_net_fops_create(net, "softnet_stat", S_IRUGO, &softnet_seq_fops))
4260		goto out_dev;
4261	if (!proc_net_fops_create(net, "ptype", S_IRUGO, &ptype_seq_fops))
4262		goto out_softnet;
 
 
4263
4264	if (wext_proc_init(net))
4265		goto out_ptype;
4266	rc = 0;
4267out:
4268	return rc;
4269out_ptype:
4270	proc_net_remove(net, "ptype");
4271out_softnet:
4272	proc_net_remove(net, "softnet_stat");
4273out_dev:
4274	proc_net_remove(net, "dev");
4275	goto out;
4276}
 
4277
4278static void __net_exit dev_proc_net_exit(struct net *net)
 
 
4279{
4280	wext_proc_exit(net);
 
 
 
 
 
 
4281
4282	proc_net_remove(net, "ptype");
4283	proc_net_remove(net, "softnet_stat");
4284	proc_net_remove(net, "dev");
4285}
 
4286
4287static struct pernet_operations __net_initdata dev_proc_ops = {
4288	.init = dev_proc_net_init,
4289	.exit = dev_proc_net_exit,
4290};
 
 
 
 
 
 
4291
4292static int __init dev_proc_init(void)
 
 
4293{
4294	return register_pernet_subsys(&dev_proc_ops);
 
 
 
 
4295}
4296#else
4297#define dev_proc_init() 0
4298#endif	/* CONFIG_PROC_FS */
 
 
 
4299
 
 
 
 
4300
4301/**
4302 *	netdev_set_master	-	set up master pointer
4303 *	@slave: slave device
4304 *	@master: new master device
4305 *
4306 *	Changes the master device of the slave. Pass %NULL to break the
4307 *	bonding. The caller must hold the RTNL semaphore. On a failure
4308 *	a negative errno code is returned. On success the reference counts
4309 *	are adjusted and the function returns zero.
4310 */
4311int netdev_set_master(struct net_device *slave, struct net_device *master)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4312{
4313	struct net_device *old = slave->master;
 
 
4314
4315	ASSERT_RTNL();
 
 
 
 
 
 
 
4316
4317	if (master) {
4318		if (old)
4319			return -EBUSY;
4320		dev_hold(master);
 
 
 
4321	}
 
4322
4323	slave->master = master;
 
 
 
4324
4325	if (old)
4326		dev_put(old);
4327	return 0;
 
 
 
 
4328}
4329EXPORT_SYMBOL(netdev_set_master);
 
4330
4331/**
4332 *	netdev_set_bond_master	-	set up bonding master/slave pair
4333 *	@slave: slave device
4334 *	@master: new master device
4335 *
4336 *	Changes the master device of the slave. Pass %NULL to break the
4337 *	bonding. The caller must hold the RTNL semaphore. On a failure
4338 *	a negative errno code is returned. On success %RTM_NEWLINK is sent
4339 *	to the routing socket and the function returns zero.
4340 */
4341int netdev_set_bond_master(struct net_device *slave, struct net_device *master)
 
4342{
4343	int err;
 
 
4344
4345	ASSERT_RTNL();
4346
4347	err = netdev_set_master(slave, master);
4348	if (err)
4349		return err;
4350	if (master)
4351		slave->flags |= IFF_SLAVE;
4352	else
4353		slave->flags &= ~IFF_SLAVE;
4354
4355	rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE);
4356	return 0;
4357}
4358EXPORT_SYMBOL(netdev_set_bond_master);
4359
4360static void dev_change_rx_flags(struct net_device *dev, int flags)
4361{
4362	const struct net_device_ops *ops = dev->netdev_ops;
4363
4364	if ((dev->flags & IFF_UP) && ops->ndo_change_rx_flags)
4365		ops->ndo_change_rx_flags(dev, flags);
4366}
4367
4368static int __dev_set_promiscuity(struct net_device *dev, int inc)
4369{
4370	unsigned short old_flags = dev->flags;
4371	uid_t uid;
4372	gid_t gid;
 
4373
4374	ASSERT_RTNL();
4375
4376	dev->flags |= IFF_PROMISC;
4377	dev->promiscuity += inc;
4378	if (dev->promiscuity == 0) {
4379		/*
4380		 * Avoid overflow.
4381		 * If inc causes overflow, untouch promisc and return error.
4382		 */
4383		if (inc < 0)
4384			dev->flags &= ~IFF_PROMISC;
4385		else {
4386			dev->promiscuity -= inc;
4387			printk(KERN_WARNING "%s: promiscuity touches roof, "
4388				"set promiscuity failed, promiscuity feature "
4389				"of device might be broken.\n", dev->name);
4390			return -EOVERFLOW;
4391		}
 
 
 
4392	}
4393	if (dev->flags != old_flags) {
4394		printk(KERN_INFO "device %s %s promiscuous mode\n",
4395		       dev->name, (dev->flags & IFF_PROMISC) ? "entered" :
4396							       "left");
 
4397		if (audit_enabled) {
4398			current_uid_gid(&uid, &gid);
4399			audit_log(current->audit_context, GFP_ATOMIC,
4400				AUDIT_ANOM_PROMISCUOUS,
4401				"dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
4402				dev->name, (dev->flags & IFF_PROMISC),
4403				(old_flags & IFF_PROMISC),
4404				audit_get_loginuid(current),
4405				uid, gid,
4406				audit_get_sessionid(current));
 
4407		}
4408
4409		dev_change_rx_flags(dev, IFF_PROMISC);
4410	}
 
 
4411	return 0;
4412}
4413
4414/**
4415 *	dev_set_promiscuity	- update promiscuity count on a device
4416 *	@dev: device
4417 *	@inc: modifier
4418 *
4419 *	Add or remove promiscuity from a device. While the count in the device
4420 *	remains above zero the interface remains promiscuous. Once it hits zero
4421 *	the device reverts back to normal filtering operation. A negative inc
4422 *	value is used to drop promiscuity on the device.
4423 *	Return 0 if successful or a negative errno code on error.
4424 */
4425int dev_set_promiscuity(struct net_device *dev, int inc)
4426{
4427	unsigned short old_flags = dev->flags;
4428	int err;
4429
4430	err = __dev_set_promiscuity(dev, inc);
4431	if (err < 0)
4432		return err;
4433	if (dev->flags != old_flags)
4434		dev_set_rx_mode(dev);
4435	return err;
4436}
4437EXPORT_SYMBOL(dev_set_promiscuity);
4438
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4439/**
4440 *	dev_set_allmulti	- update allmulti count on a device
4441 *	@dev: device
4442 *	@inc: modifier
4443 *
4444 *	Add or remove reception of all multicast frames to a device. While the
4445 *	count in the device remains above zero the interface remains listening
4446 *	to all interfaces. Once it hits zero the device reverts back to normal
4447 *	filtering operation. A negative @inc value is used to drop the counter
4448 *	when releasing a resource needing all multicasts.
4449 *	Return 0 if successful or a negative errno code on error.
4450 */
4451
4452int dev_set_allmulti(struct net_device *dev, int inc)
4453{
4454	unsigned short old_flags = dev->flags;
4455
4456	ASSERT_RTNL();
4457
4458	dev->flags |= IFF_ALLMULTI;
4459	dev->allmulti += inc;
4460	if (dev->allmulti == 0) {
4461		/*
4462		 * Avoid overflow.
4463		 * If inc causes overflow, untouch allmulti and return error.
4464		 */
4465		if (inc < 0)
4466			dev->flags &= ~IFF_ALLMULTI;
4467		else {
4468			dev->allmulti -= inc;
4469			printk(KERN_WARNING "%s: allmulti touches roof, "
4470				"set allmulti failed, allmulti feature of "
4471				"device might be broken.\n", dev->name);
4472			return -EOVERFLOW;
4473		}
4474	}
4475	if (dev->flags ^ old_flags) {
4476		dev_change_rx_flags(dev, IFF_ALLMULTI);
4477		dev_set_rx_mode(dev);
4478	}
4479	return 0;
4480}
4481EXPORT_SYMBOL(dev_set_allmulti);
4482
4483/*
4484 *	Upload unicast and multicast address lists to device and
4485 *	configure RX filtering. When the device doesn't support unicast
4486 *	filtering it is put in promiscuous mode while unicast addresses
4487 *	are present.
4488 */
4489void __dev_set_rx_mode(struct net_device *dev)
4490{
4491	const struct net_device_ops *ops = dev->netdev_ops;
4492
4493	/* dev_open will call this function so the list will stay sane. */
4494	if (!(dev->flags&IFF_UP))
4495		return;
4496
4497	if (!netif_device_present(dev))
4498		return;
4499
4500	if (ops->ndo_set_rx_mode)
4501		ops->ndo_set_rx_mode(dev);
4502	else {
4503		/* Unicast addresses changes may only happen under the rtnl,
4504		 * therefore calling __dev_set_promiscuity here is safe.
4505		 */
4506		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
4507			__dev_set_promiscuity(dev, 1);
4508			dev->uc_promisc = true;
4509		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {
4510			__dev_set_promiscuity(dev, -1);
4511			dev->uc_promisc = false;
4512		}
 
4513
4514		if (ops->ndo_set_multicast_list)
4515			ops->ndo_set_multicast_list(dev);
4516	}
4517}
4518
4519void dev_set_rx_mode(struct net_device *dev)
4520{
4521	netif_addr_lock_bh(dev);
4522	__dev_set_rx_mode(dev);
4523	netif_addr_unlock_bh(dev);
4524}
4525
4526/**
4527 *	dev_ethtool_get_settings - call device's ethtool_ops::get_settings()
4528 *	@dev: device
4529 *	@cmd: memory area for ethtool_ops::get_settings() result
4530 *
4531 *      The cmd arg is initialized properly (cleared and
4532 *      ethtool_cmd::cmd field set to ETHTOOL_GSET).
4533 *
4534 *	Return device's ethtool_ops::get_settings() result value or
4535 *	-EOPNOTSUPP when device doesn't expose
4536 *	ethtool_ops::get_settings() operation.
4537 */
4538int dev_ethtool_get_settings(struct net_device *dev,
4539			     struct ethtool_cmd *cmd)
4540{
4541	if (!dev->ethtool_ops || !dev->ethtool_ops->get_settings)
4542		return -EOPNOTSUPP;
4543
4544	memset(cmd, 0, sizeof(struct ethtool_cmd));
4545	cmd->cmd = ETHTOOL_GSET;
4546	return dev->ethtool_ops->get_settings(dev, cmd);
4547}
4548EXPORT_SYMBOL(dev_ethtool_get_settings);
4549
4550/**
4551 *	dev_get_flags - get flags reported to userspace
4552 *	@dev: device
4553 *
4554 *	Get the combination of flag bits exported through APIs to userspace.
4555 */
4556unsigned dev_get_flags(const struct net_device *dev)
4557{
4558	unsigned flags;
4559
4560	flags = (dev->flags & ~(IFF_PROMISC |
4561				IFF_ALLMULTI |
4562				IFF_RUNNING |
4563				IFF_LOWER_UP |
4564				IFF_DORMANT)) |
4565		(dev->gflags & (IFF_PROMISC |
4566				IFF_ALLMULTI));
4567
4568	if (netif_running(dev)) {
4569		if (netif_oper_up(dev))
4570			flags |= IFF_RUNNING;
4571		if (netif_carrier_ok(dev))
4572			flags |= IFF_LOWER_UP;
4573		if (netif_dormant(dev))
4574			flags |= IFF_DORMANT;
4575	}
4576
4577	return flags;
4578}
4579EXPORT_SYMBOL(dev_get_flags);
4580
4581int __dev_change_flags(struct net_device *dev, unsigned int flags)
 
4582{
4583	int old_flags = dev->flags;
4584	int ret;
4585
4586	ASSERT_RTNL();
4587
4588	/*
4589	 *	Set the flags on our device.
4590	 */
4591
4592	dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
4593			       IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
4594			       IFF_AUTOMEDIA)) |
4595		     (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
4596				    IFF_ALLMULTI));
4597
4598	/*
4599	 *	Load in the correct multicast list now the flags have changed.
4600	 */
4601
4602	if ((old_flags ^ flags) & IFF_MULTICAST)
4603		dev_change_rx_flags(dev, IFF_MULTICAST);
4604
4605	dev_set_rx_mode(dev);
4606
4607	/*
4608	 *	Have we downed the interface. We handle IFF_UP ourselves
4609	 *	according to user attempts to set it, rather than blindly
4610	 *	setting it.
4611	 */
4612
4613	ret = 0;
4614	if ((old_flags ^ flags) & IFF_UP) {	/* Bit is different  ? */
4615		ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
4616
4617		if (!ret)
4618			dev_set_rx_mode(dev);
4619	}
4620
4621	if ((flags ^ dev->gflags) & IFF_PROMISC) {
4622		int inc = (flags & IFF_PROMISC) ? 1 : -1;
 
4623
4624		dev->gflags ^= IFF_PROMISC;
4625		dev_set_promiscuity(dev, inc);
 
 
 
4626	}
4627
4628	/* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
4629	   is important. Some (broken) drivers set IFF_PROMISC, when
4630	   IFF_ALLMULTI is requested not asking us and not reporting.
4631	 */
4632	if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
4633		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
4634
4635		dev->gflags ^= IFF_ALLMULTI;
4636		dev_set_allmulti(dev, inc);
4637	}
4638
4639	return ret;
4640}
4641
4642void __dev_notify_flags(struct net_device *dev, unsigned int old_flags)
 
 
4643{
4644	unsigned int changes = dev->flags ^ old_flags;
4645
 
 
 
4646	if (changes & IFF_UP) {
4647		if (dev->flags & IFF_UP)
4648			call_netdevice_notifiers(NETDEV_UP, dev);
4649		else
4650			call_netdevice_notifiers(NETDEV_DOWN, dev);
4651	}
4652
4653	if (dev->flags & IFF_UP &&
4654	    (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE)))
4655		call_netdevice_notifiers(NETDEV_CHANGE, dev);
 
 
 
 
 
 
 
 
4656}
4657
4658/**
4659 *	dev_change_flags - change device settings
4660 *	@dev: device
4661 *	@flags: device state flags
 
4662 *
4663 *	Change settings on device based state flags. The flags are
4664 *	in the userspace exported format.
4665 */
4666int dev_change_flags(struct net_device *dev, unsigned flags)
 
4667{
4668	int ret, changes;
4669	int old_flags = dev->flags;
4670
4671	ret = __dev_change_flags(dev, flags);
4672	if (ret < 0)
4673		return ret;
4674
4675	changes = old_flags ^ dev->flags;
4676	if (changes)
4677		rtmsg_ifinfo(RTM_NEWLINK, dev, changes);
4678
4679	__dev_notify_flags(dev, old_flags);
4680	return ret;
4681}
4682EXPORT_SYMBOL(dev_change_flags);
4683
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4684/**
4685 *	dev_set_mtu - Change maximum transfer unit
4686 *	@dev: device
4687 *	@new_mtu: new transfer unit
 
4688 *
4689 *	Change the maximum transfer size of the network device.
4690 */
4691int dev_set_mtu(struct net_device *dev, int new_mtu)
 
4692{
4693	const struct net_device_ops *ops = dev->netdev_ops;
4694	int err;
4695
4696	if (new_mtu == dev->mtu)
4697		return 0;
4698
4699	/*	MTU must be positive.	 */
4700	if (new_mtu < 0)
4701		return -EINVAL;
4702
4703	if (!netif_device_present(dev))
4704		return -ENODEV;
4705
4706	err = 0;
4707	if (ops->ndo_change_mtu)
4708		err = ops->ndo_change_mtu(dev, new_mtu);
4709	else
4710		dev->mtu = new_mtu;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4711
4712	if (!err && dev->flags & IFF_UP)
4713		call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
 
 
4714	return err;
4715}
4716EXPORT_SYMBOL(dev_set_mtu);
4717
4718/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4719 *	dev_set_group - Change group this device belongs to
4720 *	@dev: device
4721 *	@new_group: group this device should belong to
4722 */
4723void dev_set_group(struct net_device *dev, int new_group)
4724{
4725	dev->group = new_group;
4726}
4727EXPORT_SYMBOL(dev_set_group);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4728
4729/**
4730 *	dev_set_mac_address - Change Media Access Control Address
4731 *	@dev: device
4732 *	@sa: new address
 
4733 *
4734 *	Change the hardware (MAC) address of the device
4735 */
4736int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
 
4737{
4738	const struct net_device_ops *ops = dev->netdev_ops;
4739	int err;
4740
4741	if (!ops->ndo_set_mac_address)
4742		return -EOPNOTSUPP;
4743	if (sa->sa_family != dev->type)
4744		return -EINVAL;
4745	if (!netif_device_present(dev))
4746		return -ENODEV;
4747	err = ops->ndo_set_mac_address(dev, sa);
4748	if (!err)
4749		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
4750	return err;
 
 
 
 
 
 
 
 
4751}
4752EXPORT_SYMBOL(dev_set_mac_address);
4753
4754/*
4755 *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4756 */
4757static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
4758{
4759	int err;
4760	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
4761
4762	if (!dev)
 
 
4763		return -ENODEV;
 
 
4764
4765	switch (cmd) {
4766	case SIOCGIFFLAGS:	/* Get interface flags */
4767		ifr->ifr_flags = (short) dev_get_flags(dev);
4768		return 0;
 
 
 
 
 
 
 
4769
4770	case SIOCGIFMETRIC:	/* Get the metric on the interface
4771				   (currently unused) */
4772		ifr->ifr_metric = 0;
4773		return 0;
4774
4775	case SIOCGIFMTU:	/* Get the MTU of a device */
4776		ifr->ifr_mtu = dev->mtu;
4777		return 0;
 
 
 
 
 
 
 
 
 
 
4778
4779	case SIOCGIFHWADDR:
4780		if (!dev->addr_len)
4781			memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data);
4782		else
4783			memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
4784			       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
4785		ifr->ifr_hwaddr.sa_family = dev->type;
4786		return 0;
4787
4788	case SIOCGIFSLAVE:
4789		err = -EINVAL;
4790		break;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4791
4792	case SIOCGIFMAP:
4793		ifr->ifr_map.mem_start = dev->mem_start;
4794		ifr->ifr_map.mem_end   = dev->mem_end;
4795		ifr->ifr_map.base_addr = dev->base_addr;
4796		ifr->ifr_map.irq       = dev->irq;
4797		ifr->ifr_map.dma       = dev->dma;
4798		ifr->ifr_map.port      = dev->if_port;
4799		return 0;
4800
4801	case SIOCGIFINDEX:
4802		ifr->ifr_ifindex = dev->ifindex;
4803		return 0;
4804
4805	case SIOCGIFTXQLEN:
4806		ifr->ifr_qlen = dev->tx_queue_len;
4807		return 0;
4808
4809	default:
4810		/* dev_ioctl() should ensure this case
4811		 * is never reached
4812		 */
4813		WARN_ON(1);
4814		err = -ENOTTY;
4815		break;
4816
4817	}
4818	return err;
4819}
 
4820
4821/*
4822 *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
 
 
 
4823 */
4824static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
4825{
4826	int err;
4827	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
4828	const struct net_device_ops *ops;
 
 
 
 
 
 
 
4829
4830	if (!dev)
 
 
 
 
 
 
 
 
 
 
4831		return -ENODEV;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4832
4833	ops = dev->netdev_ops;
 
 
 
 
 
 
 
 
 
 
 
 
4834
4835	switch (cmd) {
4836	case SIOCSIFFLAGS:	/* Set interface flags */
4837		return dev_change_flags(dev, ifr->ifr_flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4838
4839	case SIOCSIFMETRIC:	/* Set the metric on the interface
4840				   (currently unused) */
4841		return -EOPNOTSUPP;
 
4842
4843	case SIOCSIFMTU:	/* Set the MTU of a device */
4844		return dev_set_mtu(dev, ifr->ifr_mtu);
 
 
4845
4846	case SIOCSIFHWADDR:
4847		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
 
 
4848
4849	case SIOCSIFHWBROADCAST:
4850		if (ifr->ifr_hwaddr.sa_family != dev->type)
4851			return -EINVAL;
4852		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
4853		       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
4854		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
4855		return 0;
4856
4857	case SIOCSIFMAP:
4858		if (ops->ndo_set_config) {
4859			if (!netif_device_present(dev))
4860				return -ENODEV;
4861			return ops->ndo_set_config(dev, &ifr->ifr_map);
4862		}
4863		return -EOPNOTSUPP;
4864
4865	case SIOCADDMULTI:
4866		if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) ||
4867		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
4868			return -EINVAL;
4869		if (!netif_device_present(dev))
4870			return -ENODEV;
4871		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
 
 
 
 
 
 
 
 
4872
4873	case SIOCDELMULTI:
4874		if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) ||
4875		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
4876			return -EINVAL;
4877		if (!netif_device_present(dev))
4878			return -ENODEV;
4879		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
4880
4881	case SIOCSIFTXQLEN:
4882		if (ifr->ifr_qlen < 0)
4883			return -EINVAL;
4884		dev->tx_queue_len = ifr->ifr_qlen;
4885		return 0;
 
4886
4887	case SIOCSIFNAME:
4888		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
4889		return dev_change_name(dev, ifr->ifr_newname);
 
 
 
4890
4891	/*
4892	 *	Unknown or private ioctl
4893	 */
4894	default:
4895		if ((cmd >= SIOCDEVPRIVATE &&
4896		    cmd <= SIOCDEVPRIVATE + 15) ||
4897		    cmd == SIOCBONDENSLAVE ||
4898		    cmd == SIOCBONDRELEASE ||
4899		    cmd == SIOCBONDSETHWADDR ||
4900		    cmd == SIOCBONDSLAVEINFOQUERY ||
4901		    cmd == SIOCBONDINFOQUERY ||
4902		    cmd == SIOCBONDCHANGEACTIVE ||
4903		    cmd == SIOCGMIIPHY ||
4904		    cmd == SIOCGMIIREG ||
4905		    cmd == SIOCSMIIREG ||
4906		    cmd == SIOCBRADDIF ||
4907		    cmd == SIOCBRDELIF ||
4908		    cmd == SIOCSHWTSTAMP ||
4909		    cmd == SIOCWANDEV) {
4910			err = -EOPNOTSUPP;
4911			if (ops->ndo_do_ioctl) {
4912				if (netif_device_present(dev))
4913					err = ops->ndo_do_ioctl(dev, ifr, cmd);
4914				else
4915					err = -ENODEV;
4916			}
4917		} else
4918			err = -EINVAL;
4919
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4920	}
4921	return err;
 
 
 
 
4922}
4923
4924/*
4925 *	This function handles all "interface"-type I/O control requests. The actual
4926 *	'doing' part of this is dev_ifsioc above.
4927 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4928
4929/**
4930 *	dev_ioctl	-	network device ioctl
4931 *	@net: the applicable net namespace
4932 *	@cmd: command to issue
4933 *	@arg: pointer to a struct ifreq in user space
4934 *
4935 *	Issue ioctl functions to devices. This is normally called by the
4936 *	user space syscall interfaces but can sometimes be useful for
4937 *	other purposes. The return value is the return from the syscall if
4938 *	positive or a negative errno code on error.
4939 */
4940
4941int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
 
 
4942{
4943	struct ifreq ifr;
4944	int ret;
4945	char *colon;
 
 
 
 
4946
4947	/* One special case: SIOCGIFCONF takes ifconf argument
4948	   and requires shared lock, because it sleeps writing
4949	   to user space.
4950	 */
4951
4952	if (cmd == SIOCGIFCONF) {
4953		rtnl_lock();
4954		ret = dev_ifconf(net, (char __user *) arg);
4955		rtnl_unlock();
4956		return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4957	}
4958	if (cmd == SIOCGIFNAME)
4959		return dev_ifname(net, (struct ifreq __user *)arg);
4960
4961	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
4962		return -EFAULT;
 
 
 
 
4963
4964	ifr.ifr_name[IFNAMSIZ-1] = 0;
 
 
 
 
 
 
4965
4966	colon = strchr(ifr.ifr_name, ':');
4967	if (colon)
4968		*colon = 0;
 
 
 
 
 
 
 
4969
4970	/*
4971	 *	See which interface the caller is talking about.
4972	 */
 
 
 
 
 
4973
4974	switch (cmd) {
4975	/*
4976	 *	These ioctl calls:
4977	 *	- can be done by all.
4978	 *	- atomic and do not require locking.
4979	 *	- return a value
4980	 */
4981	case SIOCGIFFLAGS:
4982	case SIOCGIFMETRIC:
4983	case SIOCGIFMTU:
4984	case SIOCGIFHWADDR:
4985	case SIOCGIFSLAVE:
4986	case SIOCGIFMAP:
4987	case SIOCGIFINDEX:
4988	case SIOCGIFTXQLEN:
4989		dev_load(net, ifr.ifr_name);
4990		rcu_read_lock();
4991		ret = dev_ifsioc_locked(net, &ifr, cmd);
4992		rcu_read_unlock();
4993		if (!ret) {
4994			if (colon)
4995				*colon = ':';
4996			if (copy_to_user(arg, &ifr,
4997					 sizeof(struct ifreq)))
4998				ret = -EFAULT;
 
 
4999		}
5000		return ret;
5001
5002	case SIOCETHTOOL:
5003		dev_load(net, ifr.ifr_name);
5004		rtnl_lock();
5005		ret = dev_ethtool(net, &ifr);
5006		rtnl_unlock();
5007		if (!ret) {
5008			if (colon)
5009				*colon = ':';
5010			if (copy_to_user(arg, &ifr,
5011					 sizeof(struct ifreq)))
5012				ret = -EFAULT;
5013		}
5014		return ret;
5015
5016	/*
5017	 *	These ioctl calls:
5018	 *	- require superuser power.
5019	 *	- require strict serialization.
5020	 *	- return a value
5021	 */
5022	case SIOCGMIIPHY:
5023	case SIOCGMIIREG:
5024	case SIOCSIFNAME:
5025		if (!capable(CAP_NET_ADMIN))
5026			return -EPERM;
5027		dev_load(net, ifr.ifr_name);
5028		rtnl_lock();
5029		ret = dev_ifsioc(net, &ifr, cmd);
5030		rtnl_unlock();
5031		if (!ret) {
5032			if (colon)
5033				*colon = ':';
5034			if (copy_to_user(arg, &ifr,
5035					 sizeof(struct ifreq)))
5036				ret = -EFAULT;
5037		}
5038		return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5039
5040	/*
5041	 *	These ioctl calls:
5042	 *	- require superuser power.
5043	 *	- require strict serialization.
5044	 *	- do not return a value
5045	 */
5046	case SIOCSIFFLAGS:
5047	case SIOCSIFMETRIC:
5048	case SIOCSIFMTU:
5049	case SIOCSIFMAP:
5050	case SIOCSIFHWADDR:
5051	case SIOCSIFSLAVE:
5052	case SIOCADDMULTI:
5053	case SIOCDELMULTI:
5054	case SIOCSIFHWBROADCAST:
5055	case SIOCSIFTXQLEN:
5056	case SIOCSMIIREG:
5057	case SIOCBONDENSLAVE:
5058	case SIOCBONDRELEASE:
5059	case SIOCBONDSETHWADDR:
5060	case SIOCBONDCHANGEACTIVE:
5061	case SIOCBRADDIF:
5062	case SIOCBRDELIF:
5063	case SIOCSHWTSTAMP:
5064		if (!capable(CAP_NET_ADMIN))
5065			return -EPERM;
5066		/* fall through */
5067	case SIOCBONDSLAVEINFOQUERY:
5068	case SIOCBONDINFOQUERY:
5069		dev_load(net, ifr.ifr_name);
5070		rtnl_lock();
5071		ret = dev_ifsioc(net, &ifr, cmd);
5072		rtnl_unlock();
5073		return ret;
5074
5075	case SIOCGIFMEM:
5076		/* Get the per device memory space. We can add this but
5077		 * currently do not support it */
5078	case SIOCSIFMEM:
5079		/* Set the per device memory buffer space.
5080		 * Not applicable in our case */
5081	case SIOCSIFLINK:
5082		return -ENOTTY;
5083
5084	/*
5085	 *	Unknown or private ioctl.
5086	 */
5087	default:
5088		if (cmd == SIOCWANDEV ||
5089		    (cmd >= SIOCDEVPRIVATE &&
5090		     cmd <= SIOCDEVPRIVATE + 15)) {
5091			dev_load(net, ifr.ifr_name);
5092			rtnl_lock();
5093			ret = dev_ifsioc(net, &ifr, cmd);
5094			rtnl_unlock();
5095			if (!ret && copy_to_user(arg, &ifr,
5096						 sizeof(struct ifreq)))
5097				ret = -EFAULT;
5098			return ret;
5099		}
5100		/* Take care of Wireless Extensions */
5101		if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST)
5102			return wext_handle_ioctl(net, &ifr, cmd, arg);
5103		return -ENOTTY;
5104	}
 
 
 
 
 
 
 
 
5105}
5106
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5107
5108/**
5109 *	dev_new_index	-	allocate an ifindex
5110 *	@net: the applicable net namespace
5111 *
5112 *	Returns a suitable unique value for a new device interface
5113 *	number.  The caller must hold the rtnl semaphore or the
5114 *	dev_base_lock to be sure it remains unique.
5115 */
5116static int dev_new_index(struct net *net)
5117{
5118	static int ifindex;
5119	for (;;) {
5120		if (++ifindex <= 0)
5121			ifindex = 1;
5122		if (!__dev_get_by_index(net, ifindex))
5123			return ifindex;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5124	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5125}
5126
5127/* Delayed registration/unregisteration */
5128static LIST_HEAD(net_todo_list);
 
 
 
 
 
 
5129
5130static void net_set_todo(struct net_device *dev)
5131{
5132	list_add_tail(&dev->todo_list, &net_todo_list);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5133}
5134
5135static void rollback_registered_many(struct list_head *head)
 
 
 
 
 
 
 
 
 
 
 
5136{
5137	struct net_device *dev, *tmp;
 
 
5138
5139	BUG_ON(dev_boot_phase);
5140	ASSERT_RTNL();
5141
5142	list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5143		/* Some devices call without registering
5144		 * for initialization unwind. Remove those
5145		 * devices and proceed with the remaining.
5146		 */
5147		if (dev->reg_state == NETREG_UNINITIALIZED) {
5148			pr_debug("unregister_netdevice: device %s/%p never "
5149				 "was registered\n", dev->name, dev);
5150
5151			WARN_ON(1);
5152			list_del(&dev->unreg_list);
5153			continue;
 
 
5154		}
5155		dev->dismantle = true;
5156		BUG_ON(dev->reg_state != NETREG_REGISTERED);
5157	}
5158
5159	/* If device is running, close it first. */
5160	dev_close_many(head);
 
 
 
 
 
 
 
 
 
 
 
5161
5162	list_for_each_entry(dev, head, unreg_list) {
5163		/* And unlink it from device chain. */
5164		unlist_netdevice(dev);
5165
5166		dev->reg_state = NETREG_UNREGISTERING;
5167	}
 
 
5168
5169	synchronize_net();
 
5170
5171	list_for_each_entry(dev, head, unreg_list) {
5172		/* Shutdown queueing discipline. */
5173		dev_shutdown(dev);
 
 
 
 
 
 
 
 
 
 
 
5174
 
 
 
 
5175
5176		/* Notify protocols, that we are about to destroy
5177		   this device. They should clean all the things.
5178		*/
5179		call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
 
 
 
5180
5181		if (!dev->rtnl_link_ops ||
5182		    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5183			rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);
5184
5185		/*
5186		 *	Flush the unicast and multicast chains
5187		 */
5188		dev_uc_flush(dev);
5189		dev_mc_flush(dev);
5190
5191		if (dev->netdev_ops->ndo_uninit)
5192			dev->netdev_ops->ndo_uninit(dev);
 
 
5193
5194		/* Notifier chain MUST detach us from master device. */
5195		WARN_ON(dev->master);
 
 
5196
5197		/* Remove entries from kobject tree */
5198		netdev_unregister_kobject(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
5199	}
5200
5201	/* Process any work delayed until the end of the batch */
5202	dev = list_first_entry(head, struct net_device, unreg_list);
5203	call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev);
5204
5205	rcu_barrier();
5206
5207	list_for_each_entry(dev, head, unreg_list)
5208		dev_put(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5209}
5210
5211static void rollback_registered(struct net_device *dev)
5212{
5213	LIST_HEAD(single);
 
 
5214
5215	list_add(&dev->unreg_list, &single);
5216	rollback_registered_many(&single);
5217	list_del(&single);
5218}
5219
5220static u32 netdev_fix_features(struct net_device *dev, u32 features)
 
5221{
5222	/* Fix illegal checksum combinations */
5223	if ((features & NETIF_F_HW_CSUM) &&
5224	    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5225		netdev_warn(dev, "mixed HW and IP checksum settings.\n");
5226		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
5227	}
5228
5229	if ((features & NETIF_F_NO_CSUM) &&
5230	    (features & (NETIF_F_HW_CSUM|NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5231		netdev_warn(dev, "mixed no checksumming and other settings.\n");
5232		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM|NETIF_F_HW_CSUM);
5233	}
5234
5235	/* Fix illegal SG+CSUM combinations. */
5236	if ((features & NETIF_F_SG) &&
5237	    !(features & NETIF_F_ALL_CSUM)) {
5238		netdev_dbg(dev,
5239			"Dropping NETIF_F_SG since no checksum feature.\n");
5240		features &= ~NETIF_F_SG;
5241	}
5242
5243	/* TSO requires that SG is present as well. */
5244	if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
5245		netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
5246		features &= ~NETIF_F_ALL_TSO;
5247	}
5248
 
 
 
 
5249	/* TSO ECN requires that TSO is present as well. */
5250	if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
5251		features &= ~NETIF_F_TSO_ECN;
5252
5253	/* Software GSO depends on SG. */
5254	if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
5255		netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
5256		features &= ~NETIF_F_GSO;
5257	}
5258
5259	/* UFO needs SG and checksumming */
5260	if (features & NETIF_F_UFO) {
5261		/* maybe split UFO into V4 and V6? */
5262		if (!((features & NETIF_F_GEN_CSUM) ||
5263		    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
5264			    == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5265			netdev_dbg(dev,
5266				"Dropping NETIF_F_UFO since no checksum offload features.\n");
5267			features &= ~NETIF_F_UFO;
 
 
 
 
 
 
 
 
5268		}
 
5269
5270		if (!(features & NETIF_F_SG)) {
5271			netdev_dbg(dev,
5272				"Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
5273			features &= ~NETIF_F_UFO;
 
5274		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5275	}
5276
5277	return features;
5278}
5279
5280int __netdev_update_features(struct net_device *dev)
5281{
5282	u32 features;
5283	int err = 0;
 
 
5284
5285	ASSERT_RTNL();
5286
5287	features = netdev_get_wanted_features(dev);
5288
5289	if (dev->netdev_ops->ndo_fix_features)
5290		features = dev->netdev_ops->ndo_fix_features(dev, features);
5291
5292	/* driver might be less strict about feature dependencies */
5293	features = netdev_fix_features(dev, features);
5294
 
 
 
 
5295	if (dev->features == features)
5296		return 0;
5297
5298	netdev_dbg(dev, "Features changed: 0x%08x -> 0x%08x\n",
5299		dev->features, features);
5300
5301	if (dev->netdev_ops->ndo_set_features)
5302		err = dev->netdev_ops->ndo_set_features(dev, features);
 
 
5303
5304	if (unlikely(err < 0)) {
5305		netdev_err(dev,
5306			"set_features() failed (%d); wanted 0x%08x, left 0x%08x\n",
5307			err, features, dev->features);
 
 
 
5308		return -1;
5309	}
5310
5311	if (!err)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5312		dev->features = features;
 
5313
5314	return 1;
5315}
5316
5317/**
5318 *	netdev_update_features - recalculate device features
5319 *	@dev: the device to check
5320 *
5321 *	Recalculate dev->features set and send notifications if it
5322 *	has changed. Should be called after driver or hardware dependent
5323 *	conditions might have changed that influence the features.
5324 */
5325void netdev_update_features(struct net_device *dev)
5326{
5327	if (__netdev_update_features(dev))
5328		netdev_features_change(dev);
5329}
5330EXPORT_SYMBOL(netdev_update_features);
5331
5332/**
5333 *	netdev_change_features - recalculate device features
5334 *	@dev: the device to check
5335 *
5336 *	Recalculate dev->features set and send notifications even
5337 *	if they have not changed. Should be called instead of
5338 *	netdev_update_features() if also dev->vlan_features might
5339 *	have changed to allow the changes to be propagated to stacked
5340 *	VLAN devices.
5341 */
5342void netdev_change_features(struct net_device *dev)
5343{
5344	__netdev_update_features(dev);
5345	netdev_features_change(dev);
5346}
5347EXPORT_SYMBOL(netdev_change_features);
5348
5349/**
5350 *	netif_stacked_transfer_operstate -	transfer operstate
5351 *	@rootdev: the root or lower level device to transfer state from
5352 *	@dev: the device to transfer operstate to
5353 *
5354 *	Transfer operational state from root to device. This is normally
5355 *	called when a stacking relationship exists between the root
5356 *	device and the device(a leaf device).
5357 */
5358void netif_stacked_transfer_operstate(const struct net_device *rootdev,
5359					struct net_device *dev)
5360{
5361	if (rootdev->operstate == IF_OPER_DORMANT)
5362		netif_dormant_on(dev);
5363	else
5364		netif_dormant_off(dev);
5365
5366	if (netif_carrier_ok(rootdev)) {
5367		if (!netif_carrier_ok(dev))
5368			netif_carrier_on(dev);
5369	} else {
5370		if (netif_carrier_ok(dev))
5371			netif_carrier_off(dev);
5372	}
 
 
5373}
5374EXPORT_SYMBOL(netif_stacked_transfer_operstate);
5375
5376#ifdef CONFIG_RPS
5377static int netif_alloc_rx_queues(struct net_device *dev)
5378{
5379	unsigned int i, count = dev->num_rx_queues;
5380	struct netdev_rx_queue *rx;
 
 
5381
5382	BUG_ON(count < 1);
5383
5384	rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
5385	if (!rx) {
5386		pr_err("netdev: Unable to allocate %u rx queues.\n", count);
5387		return -ENOMEM;
5388	}
5389	dev->_rx = rx;
5390
5391	for (i = 0; i < count; i++)
5392		rx[i].dev = dev;
 
 
 
 
 
 
5393	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5394}
5395#endif
5396
5397static void netdev_init_one_queue(struct net_device *dev,
5398				  struct netdev_queue *queue, void *_unused)
5399{
5400	/* Initialize queue lock */
5401	spin_lock_init(&queue->_xmit_lock);
5402	netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
5403	queue->xmit_lock_owner = -1;
5404	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
5405	queue->dev = dev;
 
 
 
 
 
 
 
 
5406}
5407
5408static int netif_alloc_netdev_queues(struct net_device *dev)
5409{
5410	unsigned int count = dev->num_tx_queues;
5411	struct netdev_queue *tx;
 
5412
5413	BUG_ON(count < 1);
 
5414
5415	tx = kcalloc(count, sizeof(struct netdev_queue), GFP_KERNEL);
5416	if (!tx) {
5417		pr_err("netdev: Unable to allocate %u tx queues.\n",
5418		       count);
5419		return -ENOMEM;
5420	}
5421	dev->_tx = tx;
5422
5423	netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
5424	spin_lock_init(&dev->tx_global_lock);
5425
5426	return 0;
5427}
5428
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5429/**
5430 *	register_netdevice	- register a network device
5431 *	@dev: device to register
5432 *
5433 *	Take a completed network device structure and add it to the kernel
5434 *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5435 *	chain. 0 is returned on success. A negative errno code is returned
5436 *	on a failure to set up the device, or if the name is a duplicate.
5437 *
5438 *	Callers must hold the rtnl semaphore. You may want
5439 *	register_netdev() instead of this.
5440 *
5441 *	BUGS:
5442 *	The locking appears insufficient to guarantee two parallel registers
5443 *	will not get the same name.
5444 */
5445
5446int register_netdevice(struct net_device *dev)
5447{
5448	int ret;
5449	struct net *net = dev_net(dev);
5450
 
 
5451	BUG_ON(dev_boot_phase);
5452	ASSERT_RTNL();
5453
5454	might_sleep();
5455
5456	/* When net_device's are persistent, this will be fatal. */
5457	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
5458	BUG_ON(!net);
5459
 
 
 
 
 
 
 
 
5460	spin_lock_init(&dev->addr_list_lock);
5461	netdev_set_addr_lockdep_class(dev);
5462
5463	dev->iflink = -1;
 
 
5464
5465	ret = dev_get_valid_name(dev, dev->name);
5466	if (ret < 0)
 
5467		goto out;
5468
5469	/* Init, if this function is available */
5470	if (dev->netdev_ops->ndo_init) {
5471		ret = dev->netdev_ops->ndo_init(dev);
5472		if (ret) {
5473			if (ret > 0)
5474				ret = -EIO;
5475			goto out;
5476		}
5477	}
5478
5479	dev->ifindex = dev_new_index(net);
5480	if (dev->iflink == -1)
5481		dev->iflink = dev->ifindex;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5482
5483	/* Transfer changeable features to wanted_features and enable
5484	 * software offloads (GSO and GRO).
5485	 */
5486	dev->hw_features |= NETIF_F_SOFT_FEATURES;
5487	dev->features |= NETIF_F_SOFT_FEATURES;
 
 
 
 
 
 
5488	dev->wanted_features = dev->features & dev->hw_features;
5489
5490	/* Turn on no cache copy if HW is doing checksum */
5491	dev->hw_features |= NETIF_F_NOCACHE_COPY;
5492	if ((dev->features & NETIF_F_ALL_CSUM) &&
5493	    !(dev->features & NETIF_F_NO_CSUM)) {
5494		dev->wanted_features |= NETIF_F_NOCACHE_COPY;
5495		dev->features |= NETIF_F_NOCACHE_COPY;
5496	}
 
 
 
 
 
 
 
 
 
5497
5498	/* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
5499	 */
5500	dev->vlan_features |= NETIF_F_HIGHDMA;
5501
 
 
 
 
 
 
 
 
5502	ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
5503	ret = notifier_to_errno(ret);
5504	if (ret)
5505		goto err_uninit;
5506
5507	ret = netdev_register_kobject(dev);
 
 
 
5508	if (ret)
5509		goto err_uninit;
5510	dev->reg_state = NETREG_REGISTERED;
5511
5512	__netdev_update_features(dev);
5513
5514	/*
5515	 *	Default initial state at registry is that the
5516	 *	device is present.
5517	 */
5518
5519	set_bit(__LINK_STATE_PRESENT, &dev->state);
5520
 
 
5521	dev_init_scheduler(dev);
5522	dev_hold(dev);
 
5523	list_netdevice(dev);
5524
 
 
 
 
 
 
 
 
 
5525	/* Notify protocols, that a new device appeared. */
5526	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
5527	ret = notifier_to_errno(ret);
5528	if (ret) {
5529		rollback_registered(dev);
5530		dev->reg_state = NETREG_UNREGISTERED;
 
 
5531	}
5532	/*
5533	 *	Prevent userspace races by waiting until the network
5534	 *	device is fully setup before sending notifications.
5535	 */
5536	if (!dev->rtnl_link_ops ||
5537	    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
5538		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
5539
5540out:
5541	return ret;
5542
 
 
 
 
 
 
5543err_uninit:
5544	if (dev->netdev_ops->ndo_uninit)
5545		dev->netdev_ops->ndo_uninit(dev);
 
 
 
 
5546	goto out;
5547}
5548EXPORT_SYMBOL(register_netdevice);
5549
5550/**
5551 *	init_dummy_netdev	- init a dummy network device for NAPI
5552 *	@dev: device to init
5553 *
5554 *	This takes a network device structure and initialize the minimum
5555 *	amount of fields so it can be used to schedule NAPI polls without
5556 *	registering a full blown interface. This is to be used by drivers
5557 *	that need to tie several hardware interfaces to a single NAPI
5558 *	poll scheduler due to HW limitations.
5559 */
5560int init_dummy_netdev(struct net_device *dev)
5561{
5562	/* Clear everything. Note we don't initialize spinlocks
5563	 * are they aren't supposed to be taken by any of the
5564	 * NAPI code and this dummy netdev is supposed to be
5565	 * only ever used for NAPI polls
5566	 */
5567	memset(dev, 0, sizeof(struct net_device));
5568
5569	/* make sure we BUG if trying to hit standard
5570	 * register/unregister code path
5571	 */
5572	dev->reg_state = NETREG_DUMMY;
5573
5574	/* NAPI wants this */
5575	INIT_LIST_HEAD(&dev->napi_list);
5576
5577	/* a dummy interface is started by default */
5578	set_bit(__LINK_STATE_PRESENT, &dev->state);
5579	set_bit(__LINK_STATE_START, &dev->state);
5580
 
 
 
5581	/* Note : We dont allocate pcpu_refcnt for dummy devices,
5582	 * because users of this 'device' dont need to change
5583	 * its refcount.
5584	 */
 
5585
5586	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5587}
5588EXPORT_SYMBOL_GPL(init_dummy_netdev);
5589
5590
5591/**
5592 *	register_netdev	- register a network device
5593 *	@dev: device to register
5594 *
5595 *	Take a completed network device structure and add it to the kernel
5596 *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
5597 *	chain. 0 is returned on success. A negative errno code is returned
5598 *	on a failure to set up the device, or if the name is a duplicate.
5599 *
5600 *	This is a wrapper around register_netdevice that takes the rtnl semaphore
5601 *	and expands the device name if you passed a format string to
5602 *	alloc_netdev.
5603 */
5604int register_netdev(struct net_device *dev)
5605{
5606	int err;
5607
5608	rtnl_lock();
 
5609	err = register_netdevice(dev);
5610	rtnl_unlock();
5611	return err;
5612}
5613EXPORT_SYMBOL(register_netdev);
5614
5615int netdev_refcnt_read(const struct net_device *dev)
5616{
 
5617	int i, refcnt = 0;
5618
5619	for_each_possible_cpu(i)
5620		refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
5621	return refcnt;
 
 
 
5622}
5623EXPORT_SYMBOL(netdev_refcnt_read);
5624
5625/*
5626 * netdev_wait_allrefs - wait until all references are gone.
 
 
 
 
 
5627 *
5628 * This is called when unregistering network devices.
5629 *
5630 * Any protocol or device that holds a reference should register
5631 * for netdevice notification, and cleanup and put back the
5632 * reference if they receive an UNREGISTER event.
5633 * We can get stuck here if buggy protocols don't correctly
5634 * call dev_put.
5635 */
5636static void netdev_wait_allrefs(struct net_device *dev)
5637{
5638	unsigned long rebroadcast_time, warning_time;
5639	int refcnt;
 
5640
5641	linkwatch_forget_dev(dev);
5642
5643	rebroadcast_time = warning_time = jiffies;
5644	refcnt = netdev_refcnt_read(dev);
 
5645
5646	while (refcnt != 0) {
5647		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
5648			rtnl_lock();
5649
5650			/* Rebroadcast unregister notification */
5651			call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5652			/* don't resend NETDEV_UNREGISTER_BATCH, _BATCH users
5653			 * should have already handle it the first time */
5654
5655			if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
5656				     &dev->state)) {
5657				/* We must not have linkwatch events
5658				 * pending on unregister. If this
5659				 * happens, we simply run the queue
5660				 * unscheduled, resulting in a noop
5661				 * for this device.
5662				 */
5663				linkwatch_run_queue();
5664			}
 
 
 
 
 
5665
5666			__rtnl_unlock();
5667
5668			rebroadcast_time = jiffies;
5669		}
5670
5671		msleep(250);
 
 
 
 
 
 
 
5672
5673		refcnt = netdev_refcnt_read(dev);
 
 
 
 
 
 
 
 
 
 
5674
5675		if (time_after(jiffies, warning_time + 10 * HZ)) {
5676			printk(KERN_EMERG "unregister_netdevice: "
5677			       "waiting for %s to become free. Usage "
5678			       "count = %d\n",
5679			       dev->name, refcnt);
5680			warning_time = jiffies;
5681		}
5682	}
5683}
5684
5685/* The sequence is:
5686 *
5687 *	rtnl_lock();
5688 *	...
5689 *	register_netdevice(x1);
5690 *	register_netdevice(x2);
5691 *	...
5692 *	unregister_netdevice(y1);
5693 *	unregister_netdevice(y2);
5694 *      ...
5695 *	rtnl_unlock();
5696 *	free_netdev(y1);
5697 *	free_netdev(y2);
5698 *
5699 * We are invoked by rtnl_unlock().
5700 * This allows us to deal with problems:
5701 * 1) We can delete sysfs objects which invoke hotplug
5702 *    without deadlocking with linkwatch via keventd.
5703 * 2) Since we run with the RTNL semaphore not held, we can sleep
5704 *    safely in order to wait for the netdev refcnt to drop to zero.
5705 *
5706 * We must not return until all unregister events added during
5707 * the interval the lock was held have been completed.
5708 */
5709void netdev_run_todo(void)
5710{
 
5711	struct list_head list;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5712
5713	/* Snapshot list, allow later requests */
5714	list_replace_init(&net_todo_list, &list);
5715
5716	__rtnl_unlock();
5717
5718	while (!list_empty(&list)) {
5719		struct net_device *dev
5720			= list_first_entry(&list, struct net_device, todo_list);
5721		list_del(&dev->todo_list);
5722
 
5723		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
5724			printk(KERN_ERR "network todo '%s' but state %d\n",
5725			       dev->name, dev->reg_state);
5726			dump_stack();
5727			continue;
5728		}
5729
5730		dev->reg_state = NETREG_UNREGISTERED;
 
 
5731
5732		on_each_cpu(flush_backlog, dev, 1);
5733
5734		netdev_wait_allrefs(dev);
 
5735
5736		/* paranoia */
5737		BUG_ON(netdev_refcnt_read(dev));
5738		WARN_ON(rcu_dereference_raw(dev->ip_ptr));
5739		WARN_ON(rcu_dereference_raw(dev->ip6_ptr));
5740		WARN_ON(dev->dn_ptr);
 
 
 
 
 
 
 
5741
5742		if (dev->destructor)
5743			dev->destructor(dev);
5744
5745		/* Free network device */
5746		kobject_put(&dev->dev.kobj);
5747	}
 
 
5748}
5749
5750/* Convert net_device_stats to rtnl_link_stats64.  They have the same
5751 * fields in the same order, with only the type differing.
 
 
5752 */
5753static void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
5754				    const struct net_device_stats *netdev_stats)
5755{
5756#if BITS_PER_LONG == 64
5757        BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
5758        memcpy(stats64, netdev_stats, sizeof(*stats64));
5759#else
5760	size_t i, n = sizeof(*stats64) / sizeof(u64);
5761	const unsigned long *src = (const unsigned long *)netdev_stats;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5762	u64 *dst = (u64 *)stats64;
5763
5764	BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
5765		     sizeof(*stats64) / sizeof(u64));
5766	for (i = 0; i < n; i++)
5767		dst[i] = src[i];
5768#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5769}
 
5770
5771/**
5772 *	dev_get_stats	- get network device statistics
5773 *	@dev: device to get statistics from
5774 *	@storage: place to store stats
5775 *
5776 *	Get network statistics from device. Return @storage.
5777 *	The device driver may provide its own method by setting
5778 *	dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
5779 *	otherwise the internal statistics structure is used.
5780 */
5781struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
5782					struct rtnl_link_stats64 *storage)
5783{
5784	const struct net_device_ops *ops = dev->netdev_ops;
 
5785
5786	if (ops->ndo_get_stats64) {
5787		memset(storage, 0, sizeof(*storage));
5788		ops->ndo_get_stats64(dev, storage);
5789	} else if (ops->ndo_get_stats) {
5790		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
 
 
 
 
5791	} else {
5792		netdev_stats_to_stats64(storage, &dev->stats);
5793	}
5794	storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5795	return storage;
5796}
5797EXPORT_SYMBOL(dev_get_stats);
5798
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5799struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
5800{
5801	struct netdev_queue *queue = dev_ingress_queue(dev);
5802
5803#ifdef CONFIG_NET_CLS_ACT
5804	if (queue)
5805		return queue;
5806	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
5807	if (!queue)
5808		return NULL;
5809	netdev_init_one_queue(dev, queue, NULL);
5810	queue->qdisc = &noop_qdisc;
5811	queue->qdisc_sleeping = &noop_qdisc;
5812	rcu_assign_pointer(dev->ingress_queue, queue);
5813#endif
5814	return queue;
5815}
5816
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5817/**
5818 *	alloc_netdev_mqs - allocate network device
5819 *	@sizeof_priv:	size of private data to allocate space for
5820 *	@name:		device name format string
5821 *	@setup:		callback to initialize device
5822 *	@txqs:		the number of TX subqueues to allocate
5823 *	@rxqs:		the number of RX subqueues to allocate
5824 *
5825 *	Allocates a struct net_device with private data area for driver use
5826 *	and performs basic initialization.  Also allocates subquue structs
5827 *	for each queue on the device.
 
5828 */
5829struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
 
5830		void (*setup)(struct net_device *),
5831		unsigned int txqs, unsigned int rxqs)
5832{
5833	struct net_device *dev;
5834	size_t alloc_size;
5835	struct net_device *p;
5836
5837	BUG_ON(strlen(name) >= sizeof(dev->name));
5838
5839	if (txqs < 1) {
5840		pr_err("alloc_netdev: Unable to allocate device "
5841		       "with zero queues.\n");
5842		return NULL;
5843	}
5844
5845#ifdef CONFIG_RPS
5846	if (rxqs < 1) {
5847		pr_err("alloc_netdev: Unable to allocate device "
5848		       "with zero RX queues.\n");
5849		return NULL;
5850	}
5851#endif
5852
5853	alloc_size = sizeof(struct net_device);
5854	if (sizeof_priv) {
5855		/* ensure 32-byte alignment of private area */
5856		alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
5857		alloc_size += sizeof_priv;
5858	}
5859	/* ensure 32-byte alignment of whole construct */
5860	alloc_size += NETDEV_ALIGN - 1;
5861
5862	p = kzalloc(alloc_size, GFP_KERNEL);
5863	if (!p) {
5864		printk(KERN_ERR "alloc_netdev: Unable to allocate device.\n");
5865		return NULL;
5866	}
5867
5868	dev = PTR_ALIGN(p, NETDEV_ALIGN);
5869	dev->padded = (char *)dev - (char *)p;
5870
 
 
5871	dev->pcpu_refcnt = alloc_percpu(int);
5872	if (!dev->pcpu_refcnt)
5873		goto free_p;
 
 
 
 
5874
5875	if (dev_addr_init(dev))
5876		goto free_pcpu;
5877
5878	dev_mc_init(dev);
5879	dev_uc_init(dev);
5880
5881	dev_net_set(dev, &init_net);
5882
5883	dev->gso_max_size = GSO_MAX_SIZE;
 
 
 
 
 
 
 
 
 
 
 
 
 
5884
5885	INIT_LIST_HEAD(&dev->napi_list);
5886	INIT_LIST_HEAD(&dev->unreg_list);
 
5887	INIT_LIST_HEAD(&dev->link_watch_list);
5888	dev->priv_flags = IFF_XMIT_DST_RELEASE;
 
 
 
 
 
 
 
 
 
 
 
5889	setup(dev);
5890
 
 
 
 
 
5891	dev->num_tx_queues = txqs;
5892	dev->real_num_tx_queues = txqs;
5893	if (netif_alloc_netdev_queues(dev))
5894		goto free_all;
5895
5896#ifdef CONFIG_RPS
5897	dev->num_rx_queues = rxqs;
5898	dev->real_num_rx_queues = rxqs;
5899	if (netif_alloc_rx_queues(dev))
5900		goto free_all;
5901#endif
 
 
 
 
 
 
 
5902
5903	strcpy(dev->name, name);
 
5904	dev->group = INIT_NETDEV_GROUP;
 
 
 
 
 
5905	return dev;
5906
5907free_all:
5908	free_netdev(dev);
5909	return NULL;
5910
5911free_pcpu:
 
5912	free_percpu(dev->pcpu_refcnt);
5913	kfree(dev->_tx);
5914#ifdef CONFIG_RPS
5915	kfree(dev->_rx);
5916#endif
5917
5918free_p:
5919	kfree(p);
5920	return NULL;
5921}
5922EXPORT_SYMBOL(alloc_netdev_mqs);
5923
5924/**
5925 *	free_netdev - free network device
5926 *	@dev: device
5927 *
5928 *	This function does the last stage of destroying an allocated device
5929 * 	interface. The reference to the device object is released.
5930 *	If this is the last reference then it will be freed.
 
5931 */
5932void free_netdev(struct net_device *dev)
5933{
5934	struct napi_struct *p, *n;
5935
5936	release_net(dev_net(dev));
 
 
 
 
 
 
 
 
 
 
 
 
5937
5938	kfree(dev->_tx);
5939#ifdef CONFIG_RPS
5940	kfree(dev->_rx);
5941#endif
5942
5943	kfree(rcu_dereference_raw(dev->ingress_queue));
5944
5945	/* Flush device addresses */
5946	dev_addr_flush(dev);
5947
5948	list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
5949		netif_napi_del(p);
5950
 
 
 
 
5951	free_percpu(dev->pcpu_refcnt);
5952	dev->pcpu_refcnt = NULL;
 
 
 
 
 
 
 
5953
5954	/*  Compatibility with error handling in drivers */
5955	if (dev->reg_state == NETREG_UNINITIALIZED) {
5956		kfree((char *)dev - dev->padded);
 
5957		return;
5958	}
5959
5960	BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
5961	dev->reg_state = NETREG_RELEASED;
5962
5963	/* will free via device release */
5964	put_device(&dev->dev);
5965}
5966EXPORT_SYMBOL(free_netdev);
5967
5968/**
 
 
 
 
 
 
 
 
 
 
 
 
 
5969 *	synchronize_net -  Synchronize with packet receive processing
5970 *
5971 *	Wait for packets currently being received to be done.
5972 *	Does not block later packets from starting.
5973 */
5974void synchronize_net(void)
5975{
5976	might_sleep();
5977	if (rtnl_is_locked())
5978		synchronize_rcu_expedited();
5979	else
5980		synchronize_rcu();
5981}
5982EXPORT_SYMBOL(synchronize_net);
5983
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5984/**
5985 *	unregister_netdevice_queue - remove device from the kernel
5986 *	@dev: device
5987 *	@head: list
5988 *
5989 *	This function shuts down a device interface and removes it
5990 *	from the kernel tables.
5991 *	If head not NULL, device is queued to be unregistered later.
5992 *
5993 *	Callers must hold the rtnl semaphore.  You may want
5994 *	unregister_netdev() instead of this.
5995 */
5996
5997void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
5998{
5999	ASSERT_RTNL();
6000
6001	if (head) {
6002		list_move_tail(&dev->unreg_list, head);
6003	} else {
6004		rollback_registered(dev);
6005		/* Finish processing unregister after unlock */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6006		net_set_todo(dev);
 
6007	}
 
 
 
6008}
6009EXPORT_SYMBOL(unregister_netdevice_queue);
6010
6011/**
6012 *	unregister_netdevice_many - unregister many devices
6013 *	@head: list of devices
 
 
 
6014 */
6015void unregister_netdevice_many(struct list_head *head)
6016{
6017	struct net_device *dev;
6018
6019	if (!list_empty(head)) {
6020		rollback_registered_many(head);
6021		list_for_each_entry(dev, head, unreg_list)
6022			net_set_todo(dev);
6023	}
6024}
6025EXPORT_SYMBOL(unregister_netdevice_many);
6026
6027/**
6028 *	unregister_netdev - remove device from the kernel
6029 *	@dev: device
6030 *
6031 *	This function shuts down a device interface and removes it
6032 *	from the kernel tables.
6033 *
6034 *	This is just a wrapper for unregister_netdevice that takes
6035 *	the rtnl semaphore.  In general you want to use this and not
6036 *	unregister_netdevice.
6037 */
6038void unregister_netdev(struct net_device *dev)
6039{
6040	rtnl_lock();
6041	unregister_netdevice(dev);
6042	rtnl_unlock();
6043}
6044EXPORT_SYMBOL(unregister_netdev);
6045
6046/**
6047 *	dev_change_net_namespace - move device to different nethost namespace
6048 *	@dev: device
6049 *	@net: network namespace
6050 *	@pat: If not NULL name pattern to try if the current device name
6051 *	      is already taken in the destination network namespace.
 
 
6052 *
6053 *	This function shuts down a device interface and moves it
6054 *	to a new network namespace. On success 0 is returned, on
6055 *	a failure a netagive errno code is returned.
6056 *
6057 *	Callers must hold the rtnl semaphore.
6058 */
6059
6060int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
 
6061{
6062	int err;
 
 
 
6063
6064	ASSERT_RTNL();
6065
6066	/* Don't allow namespace local devices to be moved. */
6067	err = -EINVAL;
6068	if (dev->features & NETIF_F_NETNS_LOCAL)
6069		goto out;
6070
6071	/* Ensure the device has been registrered */
6072	err = -EINVAL;
6073	if (dev->reg_state != NETREG_REGISTERED)
6074		goto out;
6075
6076	/* Get out if there is nothing todo */
6077	err = 0;
6078	if (net_eq(dev_net(dev), net))
6079		goto out;
6080
6081	/* Pick the destination device name, and ensure
6082	 * we can use it in the destination network namespace.
6083	 */
6084	err = -EEXIST;
6085	if (__dev_get_by_name(net, dev->name)) {
6086		/* We get here if we can't use the current device name */
6087		if (!pat)
6088			goto out;
6089		if (dev_get_valid_name(dev, pat) < 0)
 
6090			goto out;
6091	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6092
6093	/*
6094	 * And now a mini version of register_netdevice unregister_netdevice.
6095	 */
6096
6097	/* If device is running close it first. */
6098	dev_close(dev);
6099
6100	/* And unlink it from device chain */
6101	err = -ENODEV;
6102	unlist_netdevice(dev);
6103
6104	synchronize_net();
6105
6106	/* Shutdown queueing discipline. */
6107	dev_shutdown(dev);
6108
6109	/* Notify protocols, that we are about to destroy
6110	   this device. They should clean all the things.
 
 
 
 
 
 
 
6111
6112	   Note that dev->reg_state stays at NETREG_REGISTERED.
6113	   This is wanted because this way 8021q and macvlan know
6114	   the device is just moving and can keep their slaves up.
6115	*/
6116	call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6117	call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev);
6118
6119	/*
6120	 *	Flush the unicast and multicast chains
6121	 */
6122	dev_uc_flush(dev);
6123	dev_mc_flush(dev);
6124
 
 
 
 
 
 
 
6125	/* Actually switch the network namespace */
6126	dev_net_set(dev, net);
 
6127
6128	/* If there is an ifindex conflict assign a new one */
6129	if (__dev_get_by_index(net, dev->ifindex)) {
6130		int iflink = (dev->iflink == dev->ifindex);
6131		dev->ifindex = dev_new_index(net);
6132		if (iflink)
6133			dev->iflink = dev->ifindex;
6134	}
6135
6136	/* Fixup kobjects */
 
6137	err = device_rename(&dev->dev, dev->name);
 
 
 
 
 
 
 
 
 
 
 
6138	WARN_ON(err);
6139
6140	/* Add the device back in the hashes */
6141	list_netdevice(dev);
6142
6143	/* Notify protocols, that a new device appeared. */
6144	call_netdevice_notifiers(NETDEV_REGISTER, dev);
6145
6146	/*
6147	 *	Prevent userspace races by waiting until the network
6148	 *	device is fully setup before sending notifications.
6149	 */
6150	rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
6151
6152	synchronize_net();
6153	err = 0;
6154out:
6155	return err;
6156}
6157EXPORT_SYMBOL_GPL(dev_change_net_namespace);
6158
6159static int dev_cpu_callback(struct notifier_block *nfb,
6160			    unsigned long action,
6161			    void *ocpu)
6162{
6163	struct sk_buff **list_skb;
6164	struct sk_buff *skb;
6165	unsigned int cpu, oldcpu = (unsigned long)ocpu;
6166	struct softnet_data *sd, *oldsd;
6167
6168	if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
6169		return NOTIFY_OK;
6170
6171	local_irq_disable();
6172	cpu = smp_processor_id();
6173	sd = &per_cpu(softnet_data, cpu);
6174	oldsd = &per_cpu(softnet_data, oldcpu);
6175
6176	/* Find end of our completion_queue. */
6177	list_skb = &sd->completion_queue;
6178	while (*list_skb)
6179		list_skb = &(*list_skb)->next;
6180	/* Append completion queue from offline CPU. */
6181	*list_skb = oldsd->completion_queue;
6182	oldsd->completion_queue = NULL;
6183
6184	/* Append output queue from offline CPU. */
6185	if (oldsd->output_queue) {
6186		*sd->output_queue_tailp = oldsd->output_queue;
6187		sd->output_queue_tailp = oldsd->output_queue_tailp;
6188		oldsd->output_queue = NULL;
6189		oldsd->output_queue_tailp = &oldsd->output_queue;
6190	}
6191	/* Append NAPI poll list from offline CPU. */
6192	if (!list_empty(&oldsd->poll_list)) {
6193		list_splice_init(&oldsd->poll_list, &sd->poll_list);
6194		raise_softirq_irqoff(NET_RX_SOFTIRQ);
 
 
 
 
 
 
 
 
 
 
6195	}
6196
6197	raise_softirq_irqoff(NET_TX_SOFTIRQ);
6198	local_irq_enable();
6199
 
 
 
 
 
 
 
 
 
6200	/* Process offline CPU's input_pkt_queue */
6201	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
6202		netif_rx(skb);
6203		input_queue_head_incr(oldsd);
6204	}
6205	while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6206		netif_rx(skb);
6207		input_queue_head_incr(oldsd);
6208	}
6209
6210	return NOTIFY_OK;
6211}
6212
6213
6214/**
6215 *	netdev_increment_features - increment feature set by one
6216 *	@all: current feature set
6217 *	@one: new feature set
6218 *	@mask: mask feature set
6219 *
6220 *	Computes a new feature set after adding a device with feature set
6221 *	@one to the master device with current feature set @all.  Will not
6222 *	enable anything that is off in @mask. Returns the new feature set.
6223 */
6224u32 netdev_increment_features(u32 all, u32 one, u32 mask)
 
6225{
6226	if (mask & NETIF_F_GEN_CSUM)
6227		mask |= NETIF_F_ALL_CSUM;
6228	mask |= NETIF_F_VLAN_CHALLENGED;
6229
6230	all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
6231	all &= one | ~NETIF_F_ALL_FOR_ALL;
6232
6233	/* If device needs checksumming, downgrade to it. */
6234	if (all & (NETIF_F_ALL_CSUM & ~NETIF_F_NO_CSUM))
6235		all &= ~NETIF_F_NO_CSUM;
6236
6237	/* If one device supports hw checksumming, set for all. */
6238	if (all & NETIF_F_GEN_CSUM)
6239		all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
6240
6241	return all;
6242}
6243EXPORT_SYMBOL(netdev_increment_features);
6244
6245static struct hlist_head *netdev_create_hash(void)
6246{
6247	int i;
6248	struct hlist_head *hash;
6249
6250	hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
6251	if (hash != NULL)
6252		for (i = 0; i < NETDEV_HASHENTRIES; i++)
6253			INIT_HLIST_HEAD(&hash[i]);
6254
6255	return hash;
6256}
6257
6258/* Initialize per network namespace state */
6259static int __net_init netdev_init(struct net *net)
6260{
 
 
 
6261	INIT_LIST_HEAD(&net->dev_base_head);
6262
6263	net->dev_name_head = netdev_create_hash();
6264	if (net->dev_name_head == NULL)
6265		goto err_name;
6266
6267	net->dev_index_head = netdev_create_hash();
6268	if (net->dev_index_head == NULL)
6269		goto err_idx;
6270
 
 
 
 
6271	return 0;
6272
6273err_idx:
6274	kfree(net->dev_name_head);
6275err_name:
6276	return -ENOMEM;
6277}
6278
6279/**
6280 *	netdev_drivername - network driver for the device
6281 *	@dev: network device
6282 *
6283 *	Determine network driver for device.
6284 */
6285const char *netdev_drivername(const struct net_device *dev)
6286{
6287	const struct device_driver *driver;
6288	const struct device *parent;
6289	const char *empty = "";
6290
6291	parent = dev->dev.parent;
6292	if (!parent)
6293		return empty;
6294
6295	driver = parent->driver;
6296	if (driver && driver->name)
6297		return driver->name;
6298	return empty;
6299}
6300
6301static int __netdev_printk(const char *level, const struct net_device *dev,
6302			   struct va_format *vaf)
6303{
6304	int r;
6305
6306	if (dev && dev->dev.parent)
6307		r = dev_printk(level, dev->dev.parent, "%s: %pV",
6308			       netdev_name(dev), vaf);
6309	else if (dev)
6310		r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
6311	else
6312		r = printk("%s(NULL net_device): %pV", level, vaf);
6313
6314	return r;
 
 
 
6315}
6316
6317int netdev_printk(const char *level, const struct net_device *dev,
6318		  const char *format, ...)
6319{
6320	struct va_format vaf;
6321	va_list args;
6322	int r;
6323
6324	va_start(args, format);
6325
6326	vaf.fmt = format;
6327	vaf.va = &args;
6328
6329	r = __netdev_printk(level, dev, &vaf);
 
6330	va_end(args);
6331
6332	return r;
6333}
6334EXPORT_SYMBOL(netdev_printk);
6335
6336#define define_netdev_printk_level(func, level)			\
6337int func(const struct net_device *dev, const char *fmt, ...)	\
6338{								\
6339	int r;							\
6340	struct va_format vaf;					\
6341	va_list args;						\
6342								\
6343	va_start(args, fmt);					\
6344								\
6345	vaf.fmt = fmt;						\
6346	vaf.va = &args;						\
6347								\
6348	r = __netdev_printk(level, dev, &vaf);			\
 
6349	va_end(args);						\
6350								\
6351	return r;						\
6352}								\
6353EXPORT_SYMBOL(func);
6354
6355define_netdev_printk_level(netdev_emerg, KERN_EMERG);
6356define_netdev_printk_level(netdev_alert, KERN_ALERT);
6357define_netdev_printk_level(netdev_crit, KERN_CRIT);
6358define_netdev_printk_level(netdev_err, KERN_ERR);
6359define_netdev_printk_level(netdev_warn, KERN_WARNING);
6360define_netdev_printk_level(netdev_notice, KERN_NOTICE);
6361define_netdev_printk_level(netdev_info, KERN_INFO);
6362
6363static void __net_exit netdev_exit(struct net *net)
6364{
6365	kfree(net->dev_name_head);
6366	kfree(net->dev_index_head);
 
 
 
6367}
6368
6369static struct pernet_operations __net_initdata netdev_net_ops = {
6370	.init = netdev_init,
6371	.exit = netdev_exit,
6372};
6373
6374static void __net_exit default_device_exit(struct net *net)
6375{
 
6376	struct net_device *dev, *aux;
6377	/*
6378	 * Push all migratable network devices back to the
6379	 * initial network namespace
6380	 */
6381	rtnl_lock();
6382	for_each_netdev_safe(net, dev, aux) {
6383		int err;
6384		char fb_name[IFNAMSIZ];
6385
6386		/* Ignore unmoveable devices (i.e. loopback) */
6387		if (dev->features & NETIF_F_NETNS_LOCAL)
6388			continue;
6389
6390		/* Leave virtual devices for the generic cleanup */
6391		if (dev->rtnl_link_ops)
6392			continue;
6393
6394		/* Push remaining network devices to init_net */
6395		snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
 
 
 
 
 
 
 
6396		err = dev_change_net_namespace(dev, &init_net, fb_name);
6397		if (err) {
6398			printk(KERN_EMERG "%s: failed to move %s to init_net: %d\n",
6399				__func__, dev->name, err);
6400			BUG();
6401		}
6402	}
6403	rtnl_unlock();
6404}
6405
6406static void __net_exit default_device_exit_batch(struct list_head *net_list)
6407{
6408	/* At exit all network devices most be removed from a network
6409	 * namespace.  Do this in the reverse order of registration.
6410	 * Do this across as many network namespaces as possible to
6411	 * improve batching efficiency.
6412	 */
6413	struct net_device *dev;
6414	struct net *net;
6415	LIST_HEAD(dev_kill_list);
6416
6417	rtnl_lock();
6418	list_for_each_entry(net, net_list, exit_list) {
 
 
 
 
 
6419		for_each_netdev_reverse(net, dev) {
6420			if (dev->rtnl_link_ops)
6421				dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
6422			else
6423				unregister_netdevice_queue(dev, &dev_kill_list);
6424		}
6425	}
6426	unregister_netdevice_many(&dev_kill_list);
6427	list_del(&dev_kill_list);
6428	rtnl_unlock();
6429}
6430
6431static struct pernet_operations __net_initdata default_device_ops = {
6432	.exit = default_device_exit,
6433	.exit_batch = default_device_exit_batch,
6434};
6435
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6436/*
6437 *	Initialize the DEV module. At boot time this walks the device list and
6438 *	unhooks any devices that fail to initialise (normally hardware not
6439 *	present) and leaves us with a valid list of present and active devices.
6440 *
6441 */
6442
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6443/*
6444 *       This is called single threaded during boot, so no need
6445 *       to take the rtnl semaphore.
6446 */
6447static int __init net_dev_init(void)
6448{
6449	int i, rc = -ENOMEM;
6450
6451	BUG_ON(!dev_boot_phase);
6452
 
 
6453	if (dev_proc_init())
6454		goto out;
6455
6456	if (netdev_kobject_init())
6457		goto out;
6458
6459	INIT_LIST_HEAD(&ptype_all);
6460	for (i = 0; i < PTYPE_HASH_SIZE; i++)
6461		INIT_LIST_HEAD(&ptype_base[i]);
6462
6463	if (register_pernet_subsys(&netdev_net_ops))
6464		goto out;
6465
6466	/*
6467	 *	Initialise the packet receive queues.
6468	 */
6469
6470	for_each_possible_cpu(i) {
 
6471		struct softnet_data *sd = &per_cpu(softnet_data, i);
6472
6473		memset(sd, 0, sizeof(*sd));
 
6474		skb_queue_head_init(&sd->input_pkt_queue);
6475		skb_queue_head_init(&sd->process_queue);
6476		sd->completion_queue = NULL;
 
 
6477		INIT_LIST_HEAD(&sd->poll_list);
6478		sd->output_queue = NULL;
6479		sd->output_queue_tailp = &sd->output_queue;
6480#ifdef CONFIG_RPS
6481		sd->csd.func = rps_trigger_softirq;
6482		sd->csd.info = sd;
6483		sd->csd.flags = 0;
6484		sd->cpu = i;
6485#endif
 
 
6486
 
6487		sd->backlog.poll = process_backlog;
6488		sd->backlog.weight = weight_p;
6489		sd->backlog.gro_list = NULL;
6490		sd->backlog.gro_count = 0;
 
 
6491	}
 
 
6492
6493	dev_boot_phase = 0;
6494
6495	/* The loopback device is special if any other network devices
6496	 * is present in a network namespace the loopback device must
6497	 * be present. Since we now dynamically allocate and free the
6498	 * loopback device ensure this invariant is maintained by
6499	 * keeping the loopback device as the first device on the
6500	 * list of network devices.  Ensuring the loopback devices
6501	 * is the first device that appears and the last network device
6502	 * that disappears.
6503	 */
6504	if (register_pernet_device(&loopback_net_ops))
6505		goto out;
6506
6507	if (register_pernet_device(&default_device_ops))
6508		goto out;
6509
6510	open_softirq(NET_TX_SOFTIRQ, net_tx_action);
6511	open_softirq(NET_RX_SOFTIRQ, net_rx_action);
6512
6513	hotcpu_notifier(dev_cpu_callback, 0);
6514	dst_init();
6515	dev_mcast_init();
6516	rc = 0;
 
 
 
 
6517out:
 
 
 
 
 
 
 
 
 
 
 
 
 
6518	return rc;
6519}
6520
6521subsys_initcall(net_dev_init);
6522
6523static int __init initialize_hashrnd(void)
6524{
6525	get_random_bytes(&hashrnd, sizeof(hashrnd));
6526	return 0;
6527}
6528
6529late_initcall_sync(initialize_hashrnd);
6530