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/bitops.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/mm.h>
   81#include <linux/mutex.h>
   82#include <linux/rwsem.h>
   83#include <linux/string.h>
   84#include <linux/mm.h>
   85#include <linux/socket.h>
   86#include <linux/sockios.h>
   87#include <linux/errno.h>
   88#include <linux/interrupt.h>
   89#include <linux/if_ether.h>
   90#include <linux/netdevice.h>
   91#include <linux/etherdevice.h>
   92#include <linux/ethtool.h>
 
   93#include <linux/skbuff.h>
   94#include <linux/kthread.h>
   95#include <linux/bpf.h>
   96#include <linux/bpf_trace.h>
   97#include <net/net_namespace.h>
   98#include <net/sock.h>
   99#include <net/busy_poll.h>
  100#include <linux/rtnetlink.h>
 
 
  101#include <linux/stat.h>
  102#include <net/dsa.h>
  103#include <net/dst.h>
  104#include <net/dst_metadata.h>
  105#include <net/gro.h>
  106#include <net/pkt_sched.h>
  107#include <net/pkt_cls.h>
  108#include <net/checksum.h>
  109#include <net/xfrm.h>
  110#include <linux/highmem.h>
  111#include <linux/init.h>
 
  112#include <linux/module.h>
  113#include <linux/netpoll.h>
  114#include <linux/rcupdate.h>
  115#include <linux/delay.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 <net/mpls.h>
  127#include <linux/ipv6.h>
  128#include <linux/in.h>
  129#include <linux/jhash.h>
  130#include <linux/random.h>
  131#include <trace/events/napi.h>
  132#include <trace/events/net.h>
  133#include <trace/events/skb.h>
  134#include <trace/events/qdisc.h>
  135#include <linux/inetdevice.h>
  136#include <linux/cpu_rmap.h>
  137#include <linux/static_key.h>
  138#include <linux/hashtable.h>
  139#include <linux/vmalloc.h>
  140#include <linux/if_macvlan.h>
  141#include <linux/errqueue.h>
  142#include <linux/hrtimer.h>
  143#include <linux/netfilter_netdev.h>
  144#include <linux/crash_dump.h>
  145#include <linux/sctp.h>
  146#include <net/udp_tunnel.h>
  147#include <linux/net_namespace.h>
  148#include <linux/indirect_call_wrapper.h>
  149#include <net/devlink.h>
  150#include <linux/pm_runtime.h>
  151#include <linux/prandom.h>
  152#include <linux/once_lite.h>
  153
  154#include "dev.h"
  155#include "net-sysfs.h"
  156
 
 
  157
  158static DEFINE_SPINLOCK(ptype_lock);
  159struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
  160struct list_head ptype_all __read_mostly;	/* Taps */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  161
  162static int netif_rx_internal(struct sk_buff *skb);
  163static int call_netdevice_notifiers_info(unsigned long val,
  164					 struct netdev_notifier_info *info);
  165static int call_netdevice_notifiers_extack(unsigned long val,
  166					   struct net_device *dev,
  167					   struct netlink_ext_ack *extack);
  168static struct napi_struct *napi_by_id(unsigned int napi_id);
  169
  170/*
  171 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
  172 * semaphore.
  173 *
  174 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
  175 *
  176 * Writers must hold the rtnl semaphore while they loop through the
  177 * dev_base_head list, and hold dev_base_lock for writing when they do the
  178 * actual updates.  This allows pure readers to access the list even
  179 * while a writer is preparing to update it.
  180 *
  181 * To put it another way, dev_base_lock is held for writing only to
  182 * protect against pure readers; the rtnl semaphore provides the
  183 * protection against other writers.
  184 *
  185 * See, for example usages, register_netdevice() and
  186 * unregister_netdevice(), which must be called with the rtnl
  187 * semaphore held.
  188 */
  189DEFINE_RWLOCK(dev_base_lock);
  190EXPORT_SYMBOL(dev_base_lock);
  191
  192static DEFINE_MUTEX(ifalias_mutex);
  193
  194/* protects napi_hash addition/deletion and napi_gen_id */
  195static DEFINE_SPINLOCK(napi_hash_lock);
  196
  197static unsigned int napi_gen_id = NR_CPUS;
  198static DEFINE_READ_MOSTLY_HASHTABLE(napi_hash, 8);
  199
  200static DECLARE_RWSEM(devnet_rename_sem);
  201
  202static inline void dev_base_seq_inc(struct net *net)
  203{
  204	while (++net->dev_base_seq == 0)
  205		;
  206}
  207
  208static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
  209{
  210	unsigned int hash = full_name_hash(net, name, strnlen(name, IFNAMSIZ));
  211
  212	return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
  213}
  214
  215static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
  216{
  217	return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
  218}
  219
  220static inline void rps_lock_irqsave(struct softnet_data *sd,
  221				    unsigned long *flags)
  222{
  223	if (IS_ENABLED(CONFIG_RPS))
  224		spin_lock_irqsave(&sd->input_pkt_queue.lock, *flags);
  225	else if (!IS_ENABLED(CONFIG_PREEMPT_RT))
  226		local_irq_save(*flags);
  227}
  228
  229static inline void rps_lock_irq_disable(struct softnet_data *sd)
  230{
  231	if (IS_ENABLED(CONFIG_RPS))
  232		spin_lock_irq(&sd->input_pkt_queue.lock);
  233	else if (!IS_ENABLED(CONFIG_PREEMPT_RT))
  234		local_irq_disable();
  235}
  236
  237static inline void rps_unlock_irq_restore(struct softnet_data *sd,
  238					  unsigned long *flags)
  239{
  240	if (IS_ENABLED(CONFIG_RPS))
  241		spin_unlock_irqrestore(&sd->input_pkt_queue.lock, *flags);
  242	else if (!IS_ENABLED(CONFIG_PREEMPT_RT))
  243		local_irq_restore(*flags);
  244}
  245
  246static inline void rps_unlock_irq_enable(struct softnet_data *sd)
  247{
  248	if (IS_ENABLED(CONFIG_RPS))
  249		spin_unlock_irq(&sd->input_pkt_queue.lock);
  250	else if (!IS_ENABLED(CONFIG_PREEMPT_RT))
  251		local_irq_enable();
  252}
  253
  254static struct netdev_name_node *netdev_name_node_alloc(struct net_device *dev,
  255						       const char *name)
  256{
  257	struct netdev_name_node *name_node;
  258
  259	name_node = kmalloc(sizeof(*name_node), GFP_KERNEL);
  260	if (!name_node)
  261		return NULL;
  262	INIT_HLIST_NODE(&name_node->hlist);
  263	name_node->dev = dev;
  264	name_node->name = name;
  265	return name_node;
  266}
  267
  268static struct netdev_name_node *
  269netdev_name_node_head_alloc(struct net_device *dev)
  270{
  271	struct netdev_name_node *name_node;
  272
  273	name_node = netdev_name_node_alloc(dev, dev->name);
  274	if (!name_node)
  275		return NULL;
  276	INIT_LIST_HEAD(&name_node->list);
  277	return name_node;
  278}
  279
  280static void netdev_name_node_free(struct netdev_name_node *name_node)
  281{
  282	kfree(name_node);
  283}
  284
  285static void netdev_name_node_add(struct net *net,
  286				 struct netdev_name_node *name_node)
  287{
  288	hlist_add_head_rcu(&name_node->hlist,
  289			   dev_name_hash(net, name_node->name));
  290}
  291
  292static void netdev_name_node_del(struct netdev_name_node *name_node)
  293{
  294	hlist_del_rcu(&name_node->hlist);
  295}
  296
  297static struct netdev_name_node *netdev_name_node_lookup(struct net *net,
  298							const char *name)
  299{
  300	struct hlist_head *head = dev_name_hash(net, name);
  301	struct netdev_name_node *name_node;
  302
  303	hlist_for_each_entry(name_node, head, hlist)
  304		if (!strcmp(name_node->name, name))
  305			return name_node;
  306	return NULL;
  307}
  308
  309static struct netdev_name_node *netdev_name_node_lookup_rcu(struct net *net,
  310							    const char *name)
  311{
  312	struct hlist_head *head = dev_name_hash(net, name);
  313	struct netdev_name_node *name_node;
  314
  315	hlist_for_each_entry_rcu(name_node, head, hlist)
  316		if (!strcmp(name_node->name, name))
  317			return name_node;
  318	return NULL;
  319}
  320
  321bool netdev_name_in_use(struct net *net, const char *name)
  322{
  323	return netdev_name_node_lookup(net, name);
  324}
  325EXPORT_SYMBOL(netdev_name_in_use);
  326
  327int netdev_name_node_alt_create(struct net_device *dev, const char *name)
  328{
  329	struct netdev_name_node *name_node;
  330	struct net *net = dev_net(dev);
  331
  332	name_node = netdev_name_node_lookup(net, name);
  333	if (name_node)
  334		return -EEXIST;
  335	name_node = netdev_name_node_alloc(dev, name);
  336	if (!name_node)
  337		return -ENOMEM;
  338	netdev_name_node_add(net, name_node);
  339	/* The node that holds dev->name acts as a head of per-device list. */
  340	list_add_tail(&name_node->list, &dev->name_node->list);
  341
  342	return 0;
  343}
  344
  345static void __netdev_name_node_alt_destroy(struct netdev_name_node *name_node)
  346{
  347	list_del(&name_node->list);
  348	netdev_name_node_del(name_node);
  349	kfree(name_node->name);
  350	netdev_name_node_free(name_node);
  351}
  352
  353int netdev_name_node_alt_destroy(struct net_device *dev, const char *name)
  354{
  355	struct netdev_name_node *name_node;
  356	struct net *net = dev_net(dev);
  357
  358	name_node = netdev_name_node_lookup(net, name);
  359	if (!name_node)
  360		return -ENOENT;
  361	/* lookup might have found our primary name or a name belonging
  362	 * to another device.
  363	 */
  364	if (name_node == dev->name_node || name_node->dev != dev)
  365		return -EINVAL;
  366
  367	__netdev_name_node_alt_destroy(name_node);
  368
  369	return 0;
  370}
  371
  372static void netdev_name_node_alt_flush(struct net_device *dev)
  373{
  374	struct netdev_name_node *name_node, *tmp;
  375
  376	list_for_each_entry_safe(name_node, tmp, &dev->name_node->list, list)
  377		__netdev_name_node_alt_destroy(name_node);
  378}
  379
  380/* Device list insertion */
  381static void list_netdevice(struct net_device *dev)
  382{
  383	struct net *net = dev_net(dev);
  384
  385	ASSERT_RTNL();
  386
  387	write_lock(&dev_base_lock);
  388	list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
  389	netdev_name_node_add(net, dev->name_node);
  390	hlist_add_head_rcu(&dev->index_hlist,
  391			   dev_index_hash(net, dev->ifindex));
  392	write_unlock(&dev_base_lock);
  393
  394	dev_base_seq_inc(net);
 
 
  395}
  396
  397/* Device list removal
  398 * caller must respect a RCU grace period before freeing/reusing dev
  399 */
  400static void unlist_netdevice(struct net_device *dev, bool lock)
  401{
  402	ASSERT_RTNL();
  403
  404	/* Unlink dev from the device chain */
  405	if (lock)
  406		write_lock(&dev_base_lock);
  407	list_del_rcu(&dev->dev_list);
  408	netdev_name_node_del(dev->name_node);
  409	hlist_del_rcu(&dev->index_hlist);
  410	if (lock)
  411		write_unlock(&dev_base_lock);
  412
  413	dev_base_seq_inc(dev_net(dev));
  414}
  415
  416/*
  417 *	Our notifier list
  418 */
  419
  420static RAW_NOTIFIER_HEAD(netdev_chain);
  421
  422/*
  423 *	Device drivers call our routines to queue packets here. We empty the
  424 *	queue in the local softnet handler.
  425 */
  426
  427DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
  428EXPORT_PER_CPU_SYMBOL(softnet_data);
  429
  430#ifdef CONFIG_LOCKDEP
  431/*
  432 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
  433 * according to dev->type
  434 */
  435static const unsigned short netdev_lock_type[] = {
  436	 ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
  437	 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
  438	 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
  439	 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
  440	 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
  441	 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
  442	 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
  443	 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
  444	 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
  445	 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
  446	 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
  447	 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
  448	 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
  449	 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
  450	 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
  451
  452static const char *const netdev_lock_name[] = {
  453	"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
  454	"_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
  455	"_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
  456	"_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
  457	"_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
  458	"_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
  459	"_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
  460	"_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
  461	"_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
  462	"_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
  463	"_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
  464	"_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
  465	"_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
  466	"_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
  467	"_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
 
 
  468
  469static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
  470static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
  471
  472static inline unsigned short netdev_lock_pos(unsigned short dev_type)
  473{
  474	int i;
  475
  476	for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
  477		if (netdev_lock_type[i] == dev_type)
  478			return i;
  479	/* the last key is used by default */
  480	return ARRAY_SIZE(netdev_lock_type) - 1;
  481}
  482
  483static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
  484						 unsigned short dev_type)
  485{
  486	int i;
  487
  488	i = netdev_lock_pos(dev_type);
  489	lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
  490				   netdev_lock_name[i]);
  491}
  492
  493static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
  494{
  495	int i;
  496
  497	i = netdev_lock_pos(dev->type);
  498	lockdep_set_class_and_name(&dev->addr_list_lock,
  499				   &netdev_addr_lock_key[i],
  500				   netdev_lock_name[i]);
  501}
  502#else
  503static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
  504						 unsigned short dev_type)
  505{
  506}
  507
  508static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
  509{
  510}
  511#endif
  512
  513/*******************************************************************************
  514 *
  515 *		Protocol management and registration routines
  516 *
  517 *******************************************************************************/
  518
 
 
 
  519
  520/*
  521 *	Add a protocol ID to the list. Now that the input handler is
  522 *	smarter we can dispense with all the messy stuff that used to be
  523 *	here.
  524 *
  525 *	BEWARE!!! Protocol handlers, mangling input packets,
  526 *	MUST BE last in hash buckets and checking protocol handlers
  527 *	MUST start from promiscuous ptype_all chain in net_bh.
  528 *	It is true now, do not change it.
  529 *	Explanation follows: if protocol handler, mangling packet, will
  530 *	be the first on list, it is not able to sense, that packet
  531 *	is cloned and should be copied-on-write, so that it will
  532 *	change it and subsequent readers will get broken packet.
  533 *							--ANK (980803)
  534 */
  535
  536static inline struct list_head *ptype_head(const struct packet_type *pt)
  537{
  538	if (pt->type == htons(ETH_P_ALL))
  539		return pt->dev ? &pt->dev->ptype_all : &ptype_all;
  540	else
  541		return pt->dev ? &pt->dev->ptype_specific :
  542				 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
  543}
  544
  545/**
  546 *	dev_add_pack - add packet handler
  547 *	@pt: packet type declaration
  548 *
  549 *	Add a protocol handler to the networking stack. The passed &packet_type
  550 *	is linked into kernel lists and may not be freed until it has been
  551 *	removed from the kernel lists.
  552 *
  553 *	This call does not sleep therefore it can not
  554 *	guarantee all CPU's that are in middle of receiving packets
  555 *	will see the new packet type (until the next received packet).
  556 */
  557
  558void dev_add_pack(struct packet_type *pt)
  559{
  560	struct list_head *head = ptype_head(pt);
  561
  562	spin_lock(&ptype_lock);
  563	list_add_rcu(&pt->list, head);
  564	spin_unlock(&ptype_lock);
  565}
  566EXPORT_SYMBOL(dev_add_pack);
  567
  568/**
  569 *	__dev_remove_pack	 - remove packet handler
  570 *	@pt: packet type declaration
  571 *
  572 *	Remove a protocol handler that was previously added to the kernel
  573 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
  574 *	from the kernel lists and can be freed or reused once this function
  575 *	returns.
  576 *
  577 *      The packet type might still be in use by receivers
  578 *	and must not be freed until after all the CPU's have gone
  579 *	through a quiescent state.
  580 */
  581void __dev_remove_pack(struct packet_type *pt)
  582{
  583	struct list_head *head = ptype_head(pt);
  584	struct packet_type *pt1;
  585
  586	spin_lock(&ptype_lock);
  587
  588	list_for_each_entry(pt1, head, list) {
  589		if (pt == pt1) {
  590			list_del_rcu(&pt->list);
  591			goto out;
  592		}
  593	}
  594
  595	pr_warn("dev_remove_pack: %p not found\n", pt);
  596out:
  597	spin_unlock(&ptype_lock);
  598}
  599EXPORT_SYMBOL(__dev_remove_pack);
  600
  601/**
  602 *	dev_remove_pack	 - remove packet handler
  603 *	@pt: packet type declaration
  604 *
  605 *	Remove a protocol handler that was previously added to the kernel
  606 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
  607 *	from the kernel lists and can be freed or reused once this function
  608 *	returns.
  609 *
  610 *	This call sleeps to guarantee that no CPU is looking at the packet
  611 *	type after return.
  612 */
  613void dev_remove_pack(struct packet_type *pt)
  614{
  615	__dev_remove_pack(pt);
  616
  617	synchronize_net();
  618}
  619EXPORT_SYMBOL(dev_remove_pack);
  620
 
  621
  622/*******************************************************************************
  623 *
  624 *			    Device Interface Subroutines
  625 *
  626 *******************************************************************************/
 
  627
  628/**
  629 *	dev_get_iflink	- get 'iflink' value of a interface
  630 *	@dev: targeted interface
 
  631 *
  632 *	Indicates the ifindex the interface is linked to.
  633 *	Physical interfaces have the same 'ifindex' and 'iflink' values.
 
  634 */
  635
  636int dev_get_iflink(const struct net_device *dev)
  637{
  638	if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink)
  639		return dev->netdev_ops->ndo_get_iflink(dev);
  640
  641	return dev->ifindex;
 
 
 
 
 
 
 
 
 
 
  642}
  643EXPORT_SYMBOL(dev_get_iflink);
  644
  645/**
  646 *	dev_fill_metadata_dst - Retrieve tunnel egress information.
  647 *	@dev: targeted interface
  648 *	@skb: The packet.
  649 *
  650 *	For better visibility of tunnel traffic OVS needs to retrieve
  651 *	egress tunnel information for a packet. Following API allows
  652 *	user to get this info.
 
  653 */
  654int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
  655{
  656	struct ip_tunnel_info *info;
  657
  658	if (!dev->netdev_ops  || !dev->netdev_ops->ndo_fill_metadata_dst)
  659		return -EINVAL;
  660
  661	info = skb_tunnel_info_unclone(skb);
  662	if (!info)
  663		return -ENOMEM;
  664	if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX)))
  665		return -EINVAL;
  666
  667	return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb);
 
 
 
 
 
 
 
 
 
 
  668}
  669EXPORT_SYMBOL_GPL(dev_fill_metadata_dst);
  670
  671static struct net_device_path *dev_fwd_path(struct net_device_path_stack *stack)
 
 
 
 
 
 
 
 
 
 
 
  672{
  673	int k = stack->num_paths++;
 
 
  674
  675	if (WARN_ON_ONCE(k >= NET_DEVICE_PATH_STACK_MAX))
  676		return NULL;
 
 
 
 
 
 
  677
  678	return &stack->path[k];
 
 
 
  679}
  680
  681int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr,
  682			  struct net_device_path_stack *stack)
 
 
  683{
  684	const struct net_device *last_dev;
  685	struct net_device_path_ctx ctx = {
  686		.dev	= dev,
  687	};
  688	struct net_device_path *path;
  689	int ret = 0;
  690
  691	memcpy(ctx.daddr, daddr, sizeof(ctx.daddr));
  692	stack->num_paths = 0;
  693	while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) {
  694		last_dev = ctx.dev;
  695		path = dev_fwd_path(stack);
  696		if (!path)
  697			return -1;
 
 
 
  698
  699		memset(path, 0, sizeof(struct net_device_path));
  700		ret = ctx.dev->netdev_ops->ndo_fill_forward_path(&ctx, path);
  701		if (ret < 0)
  702			return -1;
  703
  704		if (WARN_ON_ONCE(last_dev == ctx.dev))
  705			return -1;
  706	}
  707
  708	if (!ctx.dev)
  709		return ret;
  710
  711	path = dev_fwd_path(stack);
  712	if (!path)
  713		return -1;
  714	path->type = DEV_PATH_ETHERNET;
  715	path->dev = ctx.dev;
  716
  717	return ret;
  718}
  719EXPORT_SYMBOL_GPL(dev_fill_forward_path);
  720
  721/**
  722 *	__dev_get_by_name	- find a device by its name
  723 *	@net: the applicable net namespace
  724 *	@name: name to find
  725 *
  726 *	Find an interface by name. Must be called under RTNL semaphore
  727 *	or @dev_base_lock. If the name is found a pointer to the device
  728 *	is returned. If the name is not found then %NULL is returned. The
  729 *	reference counters are not incremented so the caller must be
  730 *	careful with locks.
  731 */
  732
  733struct net_device *__dev_get_by_name(struct net *net, const char *name)
  734{
  735	struct netdev_name_node *node_name;
 
 
  736
  737	node_name = netdev_name_node_lookup(net, name);
  738	return node_name ? node_name->dev : NULL;
 
 
 
  739}
  740EXPORT_SYMBOL(__dev_get_by_name);
  741
  742/**
  743 * dev_get_by_name_rcu	- find a device by its name
  744 * @net: the applicable net namespace
  745 * @name: name to find
  746 *
  747 * Find an interface by name.
  748 * If the name is found a pointer to the device is returned.
  749 * If the name is not found then %NULL is returned.
  750 * The reference counters are not incremented so the caller must be
  751 * careful with locks. The caller must hold RCU lock.
  752 */
  753
  754struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
  755{
  756	struct netdev_name_node *node_name;
 
 
  757
  758	node_name = netdev_name_node_lookup_rcu(net, name);
  759	return node_name ? node_name->dev : NULL;
 
 
 
  760}
  761EXPORT_SYMBOL(dev_get_by_name_rcu);
  762
  763/**
  764 *	dev_get_by_name		- find a device by its name
  765 *	@net: the applicable net namespace
  766 *	@name: name to find
  767 *
  768 *	Find an interface by name. This can be called from any
  769 *	context and does its own locking. The returned handle has
  770 *	the usage count incremented and the caller must use dev_put() to
  771 *	release it when it is no longer needed. %NULL is returned if no
  772 *	matching device is found.
  773 */
  774
  775struct net_device *dev_get_by_name(struct net *net, const char *name)
  776{
  777	struct net_device *dev;
  778
  779	rcu_read_lock();
  780	dev = dev_get_by_name_rcu(net, name);
  781	dev_hold(dev);
 
  782	rcu_read_unlock();
  783	return dev;
  784}
  785EXPORT_SYMBOL(dev_get_by_name);
  786
  787/**
  788 *	__dev_get_by_index - find a device by its ifindex
  789 *	@net: the applicable net namespace
  790 *	@ifindex: index of device
  791 *
  792 *	Search for an interface by index. Returns %NULL if the device
  793 *	is not found or a pointer to the device. The device has not
  794 *	had its reference counter increased so the caller must be careful
  795 *	about locking. The caller must hold either the RTNL semaphore
  796 *	or @dev_base_lock.
  797 */
  798
  799struct net_device *__dev_get_by_index(struct net *net, int ifindex)
  800{
 
  801	struct net_device *dev;
  802	struct hlist_head *head = dev_index_hash(net, ifindex);
  803
  804	hlist_for_each_entry(dev, head, index_hlist)
  805		if (dev->ifindex == ifindex)
  806			return dev;
  807
  808	return NULL;
  809}
  810EXPORT_SYMBOL(__dev_get_by_index);
  811
  812/**
  813 *	dev_get_by_index_rcu - find a device by its ifindex
  814 *	@net: the applicable net namespace
  815 *	@ifindex: index of device
  816 *
  817 *	Search for an interface by index. Returns %NULL if the device
  818 *	is not found or a pointer to the device. The device has not
  819 *	had its reference counter increased so the caller must be careful
  820 *	about locking. The caller must hold RCU lock.
  821 */
  822
  823struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
  824{
 
  825	struct net_device *dev;
  826	struct hlist_head *head = dev_index_hash(net, ifindex);
  827
  828	hlist_for_each_entry_rcu(dev, head, index_hlist)
  829		if (dev->ifindex == ifindex)
  830			return dev;
  831
  832	return NULL;
  833}
  834EXPORT_SYMBOL(dev_get_by_index_rcu);
  835
  836
  837/**
  838 *	dev_get_by_index - find a device by its ifindex
  839 *	@net: the applicable net namespace
  840 *	@ifindex: index of device
  841 *
  842 *	Search for an interface by index. Returns NULL if the device
  843 *	is not found or a pointer to the device. The device returned has
  844 *	had a reference added and the pointer is safe until the user calls
  845 *	dev_put to indicate they have finished with it.
  846 */
  847
  848struct net_device *dev_get_by_index(struct net *net, int ifindex)
  849{
  850	struct net_device *dev;
  851
  852	rcu_read_lock();
  853	dev = dev_get_by_index_rcu(net, ifindex);
  854	dev_hold(dev);
 
  855	rcu_read_unlock();
  856	return dev;
  857}
  858EXPORT_SYMBOL(dev_get_by_index);
  859
  860/**
  861 *	dev_get_by_napi_id - find a device by napi_id
  862 *	@napi_id: ID of the NAPI struct
  863 *
  864 *	Search for an interface by NAPI ID. Returns %NULL if the device
  865 *	is not found or a pointer to the device. The device has not had
  866 *	its reference counter increased so the caller must be careful
  867 *	about locking. The caller must hold RCU lock.
  868 */
  869
  870struct net_device *dev_get_by_napi_id(unsigned int napi_id)
  871{
  872	struct napi_struct *napi;
  873
  874	WARN_ON_ONCE(!rcu_read_lock_held());
  875
  876	if (napi_id < MIN_NAPI_ID)
  877		return NULL;
  878
  879	napi = napi_by_id(napi_id);
  880
  881	return napi ? napi->dev : NULL;
  882}
  883EXPORT_SYMBOL(dev_get_by_napi_id);
  884
  885/**
  886 *	netdev_get_name - get a netdevice name, knowing its ifindex.
  887 *	@net: network namespace
  888 *	@name: a pointer to the buffer where the name will be stored.
  889 *	@ifindex: the ifindex of the interface to get the name from.
  890 */
  891int netdev_get_name(struct net *net, char *name, int ifindex)
  892{
  893	struct net_device *dev;
  894	int ret;
  895
  896	down_read(&devnet_rename_sem);
  897	rcu_read_lock();
  898
  899	dev = dev_get_by_index_rcu(net, ifindex);
  900	if (!dev) {
  901		ret = -ENODEV;
  902		goto out;
  903	}
  904
  905	strcpy(name, dev->name);
  906
  907	ret = 0;
  908out:
  909	rcu_read_unlock();
  910	up_read(&devnet_rename_sem);
  911	return ret;
  912}
  913
  914/**
  915 *	dev_getbyhwaddr_rcu - find a device by its hardware address
  916 *	@net: the applicable net namespace
  917 *	@type: media type of device
  918 *	@ha: hardware address
  919 *
  920 *	Search for an interface by MAC address. Returns NULL if the device
  921 *	is not found or a pointer to the device.
  922 *	The caller must hold RCU or RTNL.
  923 *	The returned device has not had its ref count increased
  924 *	and the caller must therefore be careful about locking
  925 *
  926 */
  927
  928struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
  929				       const char *ha)
  930{
  931	struct net_device *dev;
  932
  933	for_each_netdev_rcu(net, dev)
  934		if (dev->type == type &&
  935		    !memcmp(dev->dev_addr, ha, dev->addr_len))
  936			return dev;
  937
  938	return NULL;
  939}
  940EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
  941
 
 
 
 
 
 
 
 
 
 
 
 
 
  942struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
  943{
  944	struct net_device *dev, *ret = NULL;
  945
  946	rcu_read_lock();
  947	for_each_netdev_rcu(net, dev)
  948		if (dev->type == type) {
  949			dev_hold(dev);
  950			ret = dev;
  951			break;
  952		}
  953	rcu_read_unlock();
  954	return ret;
  955}
  956EXPORT_SYMBOL(dev_getfirstbyhwtype);
  957
  958/**
  959 *	__dev_get_by_flags - find any device with given flags
  960 *	@net: the applicable net namespace
  961 *	@if_flags: IFF_* values
  962 *	@mask: bitmask of bits in if_flags to check
  963 *
  964 *	Search for any interface with the given flags. Returns NULL if a device
  965 *	is not found or a pointer to the device. Must be called inside
  966 *	rtnl_lock(), and result refcount is unchanged.
  967 */
  968
  969struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags,
  970				      unsigned short mask)
  971{
  972	struct net_device *dev, *ret;
  973
  974	ASSERT_RTNL();
  975
  976	ret = NULL;
  977	for_each_netdev(net, dev) {
  978		if (((dev->flags ^ if_flags) & mask) == 0) {
  979			ret = dev;
  980			break;
  981		}
  982	}
  983	return ret;
  984}
  985EXPORT_SYMBOL(__dev_get_by_flags);
  986
  987/**
  988 *	dev_valid_name - check if name is okay for network device
  989 *	@name: name string
  990 *
  991 *	Network device names need to be valid file names to
  992 *	allow sysfs to work.  We also disallow any kind of
  993 *	whitespace.
  994 */
  995bool dev_valid_name(const char *name)
  996{
  997	if (*name == '\0')
  998		return false;
  999	if (strnlen(name, IFNAMSIZ) == IFNAMSIZ)
 1000		return false;
 1001	if (!strcmp(name, ".") || !strcmp(name, ".."))
 1002		return false;
 1003
 1004	while (*name) {
 1005		if (*name == '/' || *name == ':' || isspace(*name))
 1006			return false;
 1007		name++;
 1008	}
 1009	return true;
 1010}
 1011EXPORT_SYMBOL(dev_valid_name);
 1012
 1013/**
 1014 *	__dev_alloc_name - allocate a name for a device
 1015 *	@net: network namespace to allocate the device name in
 1016 *	@name: name format string
 1017 *	@buf:  scratch buffer and result name string
 1018 *
 1019 *	Passed a format string - eg "lt%d" it will try and find a suitable
 1020 *	id. It scans list of devices to build up a free map, then chooses
 1021 *	the first empty slot. The caller must hold the dev_base or rtnl lock
 1022 *	while allocating the name and adding the device in order to avoid
 1023 *	duplicates.
 1024 *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
 1025 *	Returns the number of the unit assigned or a negative errno code.
 1026 */
 1027
 1028static int __dev_alloc_name(struct net *net, const char *name, char *buf)
 1029{
 1030	int i = 0;
 1031	const char *p;
 1032	const int max_netdevices = 8*PAGE_SIZE;
 1033	unsigned long *inuse;
 1034	struct net_device *d;
 1035
 1036	if (!dev_valid_name(name))
 1037		return -EINVAL;
 1038
 1039	p = strchr(name, '%');
 1040	if (p) {
 1041		/*
 1042		 * Verify the string as this thing may have come from
 1043		 * the user.  There must be either one "%d" and no other "%"
 1044		 * characters.
 1045		 */
 1046		if (p[1] != 'd' || strchr(p + 2, '%'))
 1047			return -EINVAL;
 1048
 1049		/* Use one page as a bit array of possible slots */
 1050		inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
 1051		if (!inuse)
 1052			return -ENOMEM;
 1053
 1054		for_each_netdev(net, d) {
 1055			struct netdev_name_node *name_node;
 1056			list_for_each_entry(name_node, &d->name_node->list, list) {
 1057				if (!sscanf(name_node->name, name, &i))
 1058					continue;
 1059				if (i < 0 || i >= max_netdevices)
 1060					continue;
 1061
 1062				/*  avoid cases where sscanf is not exact inverse of printf */
 1063				snprintf(buf, IFNAMSIZ, name, i);
 1064				if (!strncmp(buf, name_node->name, IFNAMSIZ))
 1065					__set_bit(i, inuse);
 1066			}
 1067			if (!sscanf(d->name, name, &i))
 1068				continue;
 1069			if (i < 0 || i >= max_netdevices)
 1070				continue;
 1071
 1072			/*  avoid cases where sscanf is not exact inverse of printf */
 1073			snprintf(buf, IFNAMSIZ, name, i);
 1074			if (!strncmp(buf, d->name, IFNAMSIZ))
 1075				__set_bit(i, inuse);
 1076		}
 1077
 1078		i = find_first_zero_bit(inuse, max_netdevices);
 1079		free_page((unsigned long) inuse);
 1080	}
 1081
 1082	snprintf(buf, IFNAMSIZ, name, i);
 1083	if (!netdev_name_in_use(net, buf))
 
 1084		return i;
 1085
 1086	/* It is possible to run out of possible slots
 1087	 * when the name is long and there isn't enough space left
 1088	 * for the digits, or if all bits are used.
 1089	 */
 1090	return -ENFILE;
 1091}
 1092
 1093static int dev_alloc_name_ns(struct net *net,
 1094			     struct net_device *dev,
 1095			     const char *name)
 1096{
 1097	char buf[IFNAMSIZ];
 1098	int ret;
 1099
 1100	BUG_ON(!net);
 1101	ret = __dev_alloc_name(net, name, buf);
 1102	if (ret >= 0)
 1103		strscpy(dev->name, buf, IFNAMSIZ);
 1104	return ret;
 1105}
 1106
 1107/**
 1108 *	dev_alloc_name - allocate a name for a device
 1109 *	@dev: device
 1110 *	@name: name format string
 1111 *
 1112 *	Passed a format string - eg "lt%d" it will try and find a suitable
 1113 *	id. It scans list of devices to build up a free map, then chooses
 1114 *	the first empty slot. The caller must hold the dev_base or rtnl lock
 1115 *	while allocating the name and adding the device in order to avoid
 1116 *	duplicates.
 1117 *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
 1118 *	Returns the number of the unit assigned or a negative errno code.
 1119 */
 1120
 1121int dev_alloc_name(struct net_device *dev, const char *name)
 1122{
 1123	return dev_alloc_name_ns(dev_net(dev), dev, name);
 
 
 
 
 
 
 
 
 
 1124}
 1125EXPORT_SYMBOL(dev_alloc_name);
 1126
 1127static int dev_get_valid_name(struct net *net, struct net_device *dev,
 1128			      const char *name)
 1129{
 1130	BUG_ON(!net);
 
 
 
 1131
 1132	if (!dev_valid_name(name))
 1133		return -EINVAL;
 1134
 1135	if (strchr(name, '%'))
 1136		return dev_alloc_name_ns(net, dev, name);
 1137	else if (netdev_name_in_use(net, name))
 1138		return -EEXIST;
 1139	else if (dev->name != name)
 1140		strscpy(dev->name, name, IFNAMSIZ);
 1141
 1142	return 0;
 1143}
 1144
 1145/**
 1146 *	dev_change_name - change name of a device
 1147 *	@dev: device
 1148 *	@newname: name (or format string) must be at least IFNAMSIZ
 1149 *
 1150 *	Change name of a device, can pass format strings "eth%d".
 1151 *	for wildcarding.
 1152 */
 1153int dev_change_name(struct net_device *dev, const char *newname)
 1154{
 1155	unsigned char old_assign_type;
 1156	char oldname[IFNAMSIZ];
 1157	int err = 0;
 1158	int ret;
 1159	struct net *net;
 1160
 1161	ASSERT_RTNL();
 1162	BUG_ON(!dev_net(dev));
 1163
 1164	net = dev_net(dev);
 
 
 1165
 1166	down_write(&devnet_rename_sem);
 1167
 1168	if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
 1169		up_write(&devnet_rename_sem);
 1170		return 0;
 1171	}
 1172
 1173	memcpy(oldname, dev->name, IFNAMSIZ);
 1174
 1175	err = dev_get_valid_name(net, dev, newname);
 1176	if (err < 0) {
 1177		up_write(&devnet_rename_sem);
 1178		return err;
 1179	}
 1180
 1181	if (oldname[0] && !strchr(oldname, '%'))
 1182		netdev_info(dev, "renamed from %s%s\n", oldname,
 1183			    dev->flags & IFF_UP ? " (while UP)" : "");
 1184
 1185	old_assign_type = dev->name_assign_type;
 1186	dev->name_assign_type = NET_NAME_RENAMED;
 1187
 1188rollback:
 1189	ret = device_rename(&dev->dev, dev->name);
 1190	if (ret) {
 1191		memcpy(dev->name, oldname, IFNAMSIZ);
 1192		dev->name_assign_type = old_assign_type;
 1193		up_write(&devnet_rename_sem);
 1194		return ret;
 1195	}
 1196
 1197	up_write(&devnet_rename_sem);
 1198
 1199	netdev_adjacent_rename_links(dev, oldname);
 1200
 1201	write_lock(&dev_base_lock);
 1202	netdev_name_node_del(dev->name_node);
 1203	write_unlock(&dev_base_lock);
 1204
 1205	synchronize_rcu();
 1206
 1207	write_lock(&dev_base_lock);
 1208	netdev_name_node_add(net, dev->name_node);
 1209	write_unlock(&dev_base_lock);
 1210
 1211	ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
 1212	ret = notifier_to_errno(ret);
 1213
 1214	if (ret) {
 1215		/* err >= 0 after dev_alloc_name() or stores the first errno */
 1216		if (err >= 0) {
 1217			err = ret;
 1218			down_write(&devnet_rename_sem);
 1219			memcpy(dev->name, oldname, IFNAMSIZ);
 1220			memcpy(oldname, newname, IFNAMSIZ);
 1221			dev->name_assign_type = old_assign_type;
 1222			old_assign_type = NET_NAME_RENAMED;
 1223			goto rollback;
 1224		} else {
 1225			netdev_err(dev, "name change rollback failed: %d\n",
 1226				   ret);
 
 1227		}
 1228	}
 1229
 1230	return err;
 1231}
 1232
 1233/**
 1234 *	dev_set_alias - change ifalias of a device
 1235 *	@dev: device
 1236 *	@alias: name up to IFALIASZ
 1237 *	@len: limit of bytes to copy from info
 1238 *
 1239 *	Set ifalias for a device,
 1240 */
 1241int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
 1242{
 1243	struct dev_ifalias *new_alias = NULL;
 1244
 1245	if (len >= IFALIASZ)
 1246		return -EINVAL;
 1247
 1248	if (len) {
 1249		new_alias = kmalloc(sizeof(*new_alias) + len + 1, GFP_KERNEL);
 1250		if (!new_alias)
 1251			return -ENOMEM;
 1252
 1253		memcpy(new_alias->ifalias, alias, len);
 1254		new_alias->ifalias[len] = 0;
 1255	}
 1256
 1257	mutex_lock(&ifalias_mutex);
 1258	new_alias = rcu_replace_pointer(dev->ifalias, new_alias,
 1259					mutex_is_locked(&ifalias_mutex));
 1260	mutex_unlock(&ifalias_mutex);
 1261
 1262	if (new_alias)
 1263		kfree_rcu(new_alias, rcuhead);
 1264
 
 1265	return len;
 1266}
 1267EXPORT_SYMBOL(dev_set_alias);
 1268
 1269/**
 1270 *	dev_get_alias - get ifalias of a device
 1271 *	@dev: device
 1272 *	@name: buffer to store name of ifalias
 1273 *	@len: size of buffer
 1274 *
 1275 *	get ifalias for a device.  Caller must make sure dev cannot go
 1276 *	away,  e.g. rcu read lock or own a reference count to device.
 1277 */
 1278int dev_get_alias(const struct net_device *dev, char *name, size_t len)
 1279{
 1280	const struct dev_ifalias *alias;
 1281	int ret = 0;
 1282
 1283	rcu_read_lock();
 1284	alias = rcu_dereference(dev->ifalias);
 1285	if (alias)
 1286		ret = snprintf(name, len, "%s", alias->ifalias);
 1287	rcu_read_unlock();
 1288
 1289	return ret;
 1290}
 1291
 1292/**
 1293 *	netdev_features_change - device changes features
 1294 *	@dev: device to cause notification
 1295 *
 1296 *	Called to indicate a device has changed features.
 1297 */
 1298void netdev_features_change(struct net_device *dev)
 1299{
 1300	call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
 1301}
 1302EXPORT_SYMBOL(netdev_features_change);
 1303
 1304/**
 1305 *	netdev_state_change - device changes state
 1306 *	@dev: device to cause notification
 1307 *
 1308 *	Called to indicate a device has changed state. This function calls
 1309 *	the notifier chains for netdev_chain and sends a NEWLINK message
 1310 *	to the routing socket.
 1311 */
 1312void netdev_state_change(struct net_device *dev)
 1313{
 1314	if (dev->flags & IFF_UP) {
 1315		struct netdev_notifier_change_info change_info = {
 1316			.info.dev = dev,
 1317		};
 1318
 1319		call_netdevice_notifiers_info(NETDEV_CHANGE,
 1320					      &change_info.info);
 1321		rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL, 0, NULL);
 1322	}
 1323}
 1324EXPORT_SYMBOL(netdev_state_change);
 1325
 1326/**
 1327 * __netdev_notify_peers - notify network peers about existence of @dev,
 1328 * to be called when rtnl lock is already held.
 1329 * @dev: network device
 1330 *
 1331 * Generate traffic such that interested network peers are aware of
 1332 * @dev, such as by generating a gratuitous ARP. This may be used when
 1333 * a device wants to inform the rest of the network about some sort of
 1334 * reconfiguration such as a failover event or virtual machine
 1335 * migration.
 1336 */
 1337void __netdev_notify_peers(struct net_device *dev)
 1338{
 1339	ASSERT_RTNL();
 1340	call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
 1341	call_netdevice_notifiers(NETDEV_RESEND_IGMP, dev);
 1342}
 1343EXPORT_SYMBOL(__netdev_notify_peers);
 1344
 1345/**
 1346 * netdev_notify_peers - notify network peers about existence of @dev
 1347 * @dev: network device
 
 1348 *
 1349 * Generate traffic such that interested network peers are aware of
 1350 * @dev, such as by generating a gratuitous ARP. This may be used when
 1351 * a device wants to inform the rest of the network about some sort of
 1352 * reconfiguration such as a failover event or virtual machine
 1353 * migration.
 1354 */
 1355void netdev_notify_peers(struct net_device *dev)
 1356{
 1357	rtnl_lock();
 1358	__netdev_notify_peers(dev);
 1359	rtnl_unlock();
 1360}
 1361EXPORT_SYMBOL(netdev_notify_peers);
 1362
 1363static int napi_threaded_poll(void *data);
 1364
 1365static int napi_kthread_create(struct napi_struct *n)
 1366{
 1367	int err = 0;
 
 1368
 1369	/* Create and wake up the kthread once to put it in
 1370	 * TASK_INTERRUPTIBLE mode to avoid the blocked task
 1371	 * warning and work with loadavg.
 1372	 */
 1373	n->thread = kthread_run(napi_threaded_poll, n, "napi/%s-%d",
 1374				n->dev->name, n->napi_id);
 1375	if (IS_ERR(n->thread)) {
 1376		err = PTR_ERR(n->thread);
 1377		pr_err("kthread_run failed with err %d\n", err);
 1378		n->thread = NULL;
 1379	}
 1380
 1381	return err;
 
 
 
 
 
 
 
 
 1382}
 
 1383
 1384static int __dev_open(struct net_device *dev, struct netlink_ext_ack *extack)
 1385{
 1386	const struct net_device_ops *ops = dev->netdev_ops;
 1387	int ret;
 1388
 1389	ASSERT_RTNL();
 1390	dev_addr_check(dev);
 1391
 1392	if (!netif_device_present(dev)) {
 1393		/* may be detached because parent is runtime-suspended */
 1394		if (dev->dev.parent)
 1395			pm_runtime_resume(dev->dev.parent);
 1396		if (!netif_device_present(dev))
 1397			return -ENODEV;
 1398	}
 1399
 1400	/* Block netpoll from trying to do any rx path servicing.
 1401	 * If we don't do this there is a chance ndo_poll_controller
 1402	 * or ndo_poll may be running while we open the device
 1403	 */
 1404	netpoll_poll_disable(dev);
 1405
 1406	ret = call_netdevice_notifiers_extack(NETDEV_PRE_UP, dev, extack);
 1407	ret = notifier_to_errno(ret);
 1408	if (ret)
 1409		return ret;
 1410
 1411	set_bit(__LINK_STATE_START, &dev->state);
 1412
 1413	if (ops->ndo_validate_addr)
 1414		ret = ops->ndo_validate_addr(dev);
 1415
 1416	if (!ret && ops->ndo_open)
 1417		ret = ops->ndo_open(dev);
 1418
 1419	netpoll_poll_enable(dev);
 1420
 1421	if (ret)
 1422		clear_bit(__LINK_STATE_START, &dev->state);
 1423	else {
 1424		dev->flags |= IFF_UP;
 
 1425		dev_set_rx_mode(dev);
 1426		dev_activate(dev);
 1427		add_device_randomness(dev->dev_addr, dev->addr_len);
 1428	}
 1429
 1430	return ret;
 1431}
 1432
 1433/**
 1434 *	dev_open	- prepare an interface for use.
 1435 *	@dev: device to open
 1436 *	@extack: netlink extended ack
 1437 *
 1438 *	Takes a device from down to up state. The device's private open
 1439 *	function is invoked and then the multicast lists are loaded. Finally
 1440 *	the device is moved into the up state and a %NETDEV_UP message is
 1441 *	sent to the netdev notifier chain.
 1442 *
 1443 *	Calling this function on an active interface is a nop. On a failure
 1444 *	a negative errno code is returned.
 1445 */
 1446int dev_open(struct net_device *dev, struct netlink_ext_ack *extack)
 1447{
 1448	int ret;
 1449
 1450	if (dev->flags & IFF_UP)
 1451		return 0;
 1452
 1453	ret = __dev_open(dev, extack);
 1454	if (ret < 0)
 1455		return ret;
 1456
 1457	rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL);
 1458	call_netdevice_notifiers(NETDEV_UP, dev);
 1459
 1460	return ret;
 1461}
 1462EXPORT_SYMBOL(dev_open);
 1463
 1464static void __dev_close_many(struct list_head *head)
 1465{
 1466	struct net_device *dev;
 1467
 1468	ASSERT_RTNL();
 1469	might_sleep();
 1470
 1471	list_for_each_entry(dev, head, close_list) {
 1472		/* Temporarily disable netpoll until the interface is down */
 1473		netpoll_poll_disable(dev);
 1474
 1475		call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
 1476
 1477		clear_bit(__LINK_STATE_START, &dev->state);
 1478
 1479		/* Synchronize to scheduled poll. We cannot touch poll list, it
 1480		 * can be even on different cpu. So just clear netif_running().
 1481		 *
 1482		 * dev->stop() will invoke napi_disable() on all of it's
 1483		 * napi_struct instances on this device.
 1484		 */
 1485		smp_mb__after_atomic(); /* Commit netif_running(). */
 1486	}
 1487
 1488	dev_deactivate_many(head);
 1489
 1490	list_for_each_entry(dev, head, close_list) {
 1491		const struct net_device_ops *ops = dev->netdev_ops;
 1492
 1493		/*
 1494		 *	Call the device specific close. This cannot fail.
 1495		 *	Only if device is UP
 1496		 *
 1497		 *	We allow it to be called even after a DETACH hot-plug
 1498		 *	event.
 1499		 */
 1500		if (ops->ndo_stop)
 1501			ops->ndo_stop(dev);
 1502
 1503		dev->flags &= ~IFF_UP;
 1504		netpoll_poll_enable(dev);
 1505	}
 
 
 1506}
 1507
 1508static void __dev_close(struct net_device *dev)
 1509{
 
 1510	LIST_HEAD(single);
 1511
 1512	list_add(&dev->close_list, &single);
 1513	__dev_close_many(&single);
 1514	list_del(&single);
 
 1515}
 1516
 1517void dev_close_many(struct list_head *head, bool unlink)
 1518{
 1519	struct net_device *dev, *tmp;
 
 1520
 1521	/* Remove the devices that don't need to be closed */
 1522	list_for_each_entry_safe(dev, tmp, head, close_list)
 1523		if (!(dev->flags & IFF_UP))
 1524			list_del_init(&dev->close_list);
 1525
 1526	__dev_close_many(head);
 1527
 1528	list_for_each_entry_safe(dev, tmp, head, close_list) {
 1529		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP | IFF_RUNNING, GFP_KERNEL, 0, NULL);
 1530		call_netdevice_notifiers(NETDEV_DOWN, dev);
 1531		if (unlink)
 1532			list_del_init(&dev->close_list);
 1533	}
 
 
 
 
 1534}
 1535EXPORT_SYMBOL(dev_close_many);
 1536
 1537/**
 1538 *	dev_close - shutdown an interface.
 1539 *	@dev: device to shutdown
 1540 *
 1541 *	This function moves an active device into down state. A
 1542 *	%NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
 1543 *	is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
 1544 *	chain.
 1545 */
 1546void dev_close(struct net_device *dev)
 1547{
 1548	if (dev->flags & IFF_UP) {
 1549		LIST_HEAD(single);
 1550
 1551		list_add(&dev->close_list, &single);
 1552		dev_close_many(&single, true);
 1553		list_del(&single);
 1554	}
 
 1555}
 1556EXPORT_SYMBOL(dev_close);
 1557
 1558
 1559/**
 1560 *	dev_disable_lro - disable Large Receive Offload on a device
 1561 *	@dev: device
 1562 *
 1563 *	Disable Large Receive Offload (LRO) on a net device.  Must be
 1564 *	called under RTNL.  This is needed if received packets may be
 1565 *	forwarded to another interface.
 1566 */
 1567void dev_disable_lro(struct net_device *dev)
 1568{
 1569	struct net_device *lower_dev;
 1570	struct list_head *iter;
 
 
 
 
 
 
 1571
 1572	dev->wanted_features &= ~NETIF_F_LRO;
 1573	netdev_update_features(dev);
 
 
 
 
 
 1574
 
 1575	if (unlikely(dev->features & NETIF_F_LRO))
 1576		netdev_WARN(dev, "failed to disable LRO!\n");
 1577
 1578	netdev_for_each_lower_dev(dev, lower_dev, iter)
 1579		dev_disable_lro(lower_dev);
 1580}
 1581EXPORT_SYMBOL(dev_disable_lro);
 1582
 1583/**
 1584 *	dev_disable_gro_hw - disable HW Generic Receive Offload on a device
 1585 *	@dev: device
 1586 *
 1587 *	Disable HW Generic Receive Offload (GRO_HW) on a net device.  Must be
 1588 *	called under RTNL.  This is needed if Generic XDP is installed on
 1589 *	the device.
 1590 */
 1591static void dev_disable_gro_hw(struct net_device *dev)
 1592{
 1593	dev->wanted_features &= ~NETIF_F_GRO_HW;
 1594	netdev_update_features(dev);
 1595
 1596	if (unlikely(dev->features & NETIF_F_GRO_HW))
 1597		netdev_WARN(dev, "failed to disable GRO_HW!\n");
 1598}
 1599
 1600const char *netdev_cmd_to_name(enum netdev_cmd cmd)
 1601{
 1602#define N(val) 						\
 1603	case NETDEV_##val:				\
 1604		return "NETDEV_" __stringify(val);
 1605	switch (cmd) {
 1606	N(UP) N(DOWN) N(REBOOT) N(CHANGE) N(REGISTER) N(UNREGISTER)
 1607	N(CHANGEMTU) N(CHANGEADDR) N(GOING_DOWN) N(CHANGENAME) N(FEAT_CHANGE)
 1608	N(BONDING_FAILOVER) N(PRE_UP) N(PRE_TYPE_CHANGE) N(POST_TYPE_CHANGE)
 1609	N(POST_INIT) N(PRE_UNINIT) N(RELEASE) N(NOTIFY_PEERS) N(JOIN)
 1610	N(CHANGEUPPER) N(RESEND_IGMP) N(PRECHANGEMTU) N(CHANGEINFODATA)
 1611	N(BONDING_INFO) N(PRECHANGEUPPER) N(CHANGELOWERSTATE)
 1612	N(UDP_TUNNEL_PUSH_INFO) N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN)
 1613	N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO)
 1614	N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO)
 1615	N(PRE_CHANGEADDR) N(OFFLOAD_XSTATS_ENABLE) N(OFFLOAD_XSTATS_DISABLE)
 1616	N(OFFLOAD_XSTATS_REPORT_USED) N(OFFLOAD_XSTATS_REPORT_DELTA)
 1617	}
 1618#undef N
 1619	return "UNKNOWN_NETDEV_EVENT";
 1620}
 1621EXPORT_SYMBOL_GPL(netdev_cmd_to_name);
 1622
 1623static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
 1624				   struct net_device *dev)
 1625{
 1626	struct netdev_notifier_info info = {
 1627		.dev = dev,
 1628	};
 1629
 1630	return nb->notifier_call(nb, val, &info);
 1631}
 1632
 1633static int call_netdevice_register_notifiers(struct notifier_block *nb,
 1634					     struct net_device *dev)
 1635{
 1636	int err;
 1637
 1638	err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
 1639	err = notifier_to_errno(err);
 1640	if (err)
 1641		return err;
 1642
 1643	if (!(dev->flags & IFF_UP))
 1644		return 0;
 1645
 1646	call_netdevice_notifier(nb, NETDEV_UP, dev);
 1647	return 0;
 1648}
 1649
 1650static void call_netdevice_unregister_notifiers(struct notifier_block *nb,
 1651						struct net_device *dev)
 1652{
 1653	if (dev->flags & IFF_UP) {
 1654		call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
 1655					dev);
 1656		call_netdevice_notifier(nb, NETDEV_DOWN, dev);
 1657	}
 1658	call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
 1659}
 1660
 1661static int call_netdevice_register_net_notifiers(struct notifier_block *nb,
 1662						 struct net *net)
 1663{
 1664	struct net_device *dev;
 1665	int err;
 1666
 1667	for_each_netdev(net, dev) {
 1668		err = call_netdevice_register_notifiers(nb, dev);
 1669		if (err)
 1670			goto rollback;
 1671	}
 1672	return 0;
 1673
 1674rollback:
 1675	for_each_netdev_continue_reverse(net, dev)
 1676		call_netdevice_unregister_notifiers(nb, dev);
 1677	return err;
 1678}
 1679
 1680static void call_netdevice_unregister_net_notifiers(struct notifier_block *nb,
 1681						    struct net *net)
 1682{
 1683	struct net_device *dev;
 1684
 1685	for_each_netdev(net, dev)
 1686		call_netdevice_unregister_notifiers(nb, dev);
 1687}
 1688
 1689static int dev_boot_phase = 1;
 1690
 1691/**
 1692 * register_netdevice_notifier - register a network notifier block
 1693 * @nb: notifier
 1694 *
 1695 * Register a notifier to be called when network device events occur.
 1696 * The notifier passed is linked into the kernel structures and must
 1697 * not be reused until it has been unregistered. A negative errno code
 1698 * is returned on a failure.
 1699 *
 1700 * When registered all registration and up events are replayed
 1701 * to the new notifier to allow device to have a race free
 1702 * view of the network device list.
 1703 */
 1704
 1705int register_netdevice_notifier(struct notifier_block *nb)
 1706{
 
 
 1707	struct net *net;
 1708	int err;
 1709
 1710	/* Close race with setup_net() and cleanup_net() */
 1711	down_write(&pernet_ops_rwsem);
 1712	rtnl_lock();
 1713	err = raw_notifier_chain_register(&netdev_chain, nb);
 1714	if (err)
 1715		goto unlock;
 1716	if (dev_boot_phase)
 1717		goto unlock;
 1718	for_each_net(net) {
 1719		err = call_netdevice_register_net_notifiers(nb, net);
 1720		if (err)
 1721			goto rollback;
 
 
 
 
 
 
 
 
 1722	}
 1723
 1724unlock:
 1725	rtnl_unlock();
 1726	up_write(&pernet_ops_rwsem);
 1727	return err;
 1728
 1729rollback:
 1730	for_each_net_continue_reverse(net)
 1731		call_netdevice_unregister_net_notifiers(nb, net);
 
 
 
 
 
 
 
 
 
 
 
 
 1732
 1733	raw_notifier_chain_unregister(&netdev_chain, nb);
 1734	goto unlock;
 1735}
 1736EXPORT_SYMBOL(register_netdevice_notifier);
 1737
 1738/**
 1739 * unregister_netdevice_notifier - unregister a network notifier block
 1740 * @nb: notifier
 1741 *
 1742 * Unregister a notifier previously registered by
 1743 * register_netdevice_notifier(). The notifier is unlinked into the
 1744 * kernel structures and may then be reused. A negative errno code
 1745 * is returned on a failure.
 1746 *
 1747 * After unregistering unregister and down device events are synthesized
 1748 * for all devices on the device list to the removed notifier to remove
 1749 * the need for special case cleanup code.
 1750 */
 1751
 1752int unregister_netdevice_notifier(struct notifier_block *nb)
 1753{
 1754	struct net *net;
 1755	int err;
 1756
 1757	/* Close race with setup_net() and cleanup_net() */
 1758	down_write(&pernet_ops_rwsem);
 1759	rtnl_lock();
 1760	err = raw_notifier_chain_unregister(&netdev_chain, nb);
 1761	if (err)
 1762		goto unlock;
 1763
 1764	for_each_net(net)
 1765		call_netdevice_unregister_net_notifiers(nb, net);
 1766
 1767unlock:
 1768	rtnl_unlock();
 1769	up_write(&pernet_ops_rwsem);
 1770	return err;
 1771}
 1772EXPORT_SYMBOL(unregister_netdevice_notifier);
 1773
 1774static int __register_netdevice_notifier_net(struct net *net,
 1775					     struct notifier_block *nb,
 1776					     bool ignore_call_fail)
 1777{
 1778	int err;
 1779
 1780	err = raw_notifier_chain_register(&net->netdev_chain, nb);
 1781	if (err)
 1782		return err;
 1783	if (dev_boot_phase)
 1784		return 0;
 1785
 1786	err = call_netdevice_register_net_notifiers(nb, net);
 1787	if (err && !ignore_call_fail)
 1788		goto chain_unregister;
 1789
 1790	return 0;
 1791
 1792chain_unregister:
 1793	raw_notifier_chain_unregister(&net->netdev_chain, nb);
 1794	return err;
 1795}
 1796
 1797static int __unregister_netdevice_notifier_net(struct net *net,
 1798					       struct notifier_block *nb)
 1799{
 1800	int err;
 1801
 1802	err = raw_notifier_chain_unregister(&net->netdev_chain, nb);
 1803	if (err)
 1804		return err;
 1805
 1806	call_netdevice_unregister_net_notifiers(nb, net);
 1807	return 0;
 1808}
 1809
 1810/**
 1811 * register_netdevice_notifier_net - register a per-netns network notifier block
 1812 * @net: network namespace
 1813 * @nb: notifier
 1814 *
 1815 * Register a notifier to be called when network device events occur.
 1816 * The notifier passed is linked into the kernel structures and must
 1817 * not be reused until it has been unregistered. A negative errno code
 1818 * is returned on a failure.
 1819 *
 1820 * When registered all registration and up events are replayed
 1821 * to the new notifier to allow device to have a race free
 1822 * view of the network device list.
 1823 */
 1824
 1825int register_netdevice_notifier_net(struct net *net, struct notifier_block *nb)
 1826{
 1827	int err;
 1828
 1829	rtnl_lock();
 1830	err = __register_netdevice_notifier_net(net, nb, false);
 1831	rtnl_unlock();
 1832	return err;
 1833}
 1834EXPORT_SYMBOL(register_netdevice_notifier_net);
 1835
 1836/**
 1837 * unregister_netdevice_notifier_net - unregister a per-netns
 1838 *                                     network notifier block
 1839 * @net: network namespace
 1840 * @nb: notifier
 1841 *
 1842 * Unregister a notifier previously registered by
 1843 * register_netdevice_notifier(). The notifier is unlinked into the
 1844 * kernel structures and may then be reused. A negative errno code
 1845 * is returned on a failure.
 1846 *
 1847 * After unregistering unregister and down device events are synthesized
 1848 * for all devices on the device list to the removed notifier to remove
 1849 * the need for special case cleanup code.
 1850 */
 1851
 1852int unregister_netdevice_notifier_net(struct net *net,
 1853				      struct notifier_block *nb)
 1854{
 1855	int err;
 1856
 1857	rtnl_lock();
 1858	err = __unregister_netdevice_notifier_net(net, nb);
 1859	rtnl_unlock();
 1860	return err;
 1861}
 1862EXPORT_SYMBOL(unregister_netdevice_notifier_net);
 1863
 1864static void __move_netdevice_notifier_net(struct net *src_net,
 1865					  struct net *dst_net,
 1866					  struct notifier_block *nb)
 1867{
 1868	__unregister_netdevice_notifier_net(src_net, nb);
 1869	__register_netdevice_notifier_net(dst_net, nb, true);
 1870}
 1871
 1872int register_netdevice_notifier_dev_net(struct net_device *dev,
 1873					struct notifier_block *nb,
 1874					struct netdev_net_notifier *nn)
 1875{
 1876	int err;
 1877
 1878	rtnl_lock();
 1879	err = __register_netdevice_notifier_net(dev_net(dev), nb, false);
 1880	if (!err) {
 1881		nn->nb = nb;
 1882		list_add(&nn->list, &dev->net_notifier_list);
 1883	}
 1884	rtnl_unlock();
 1885	return err;
 1886}
 1887EXPORT_SYMBOL(register_netdevice_notifier_dev_net);
 1888
 1889int unregister_netdevice_notifier_dev_net(struct net_device *dev,
 1890					  struct notifier_block *nb,
 1891					  struct netdev_net_notifier *nn)
 1892{
 1893	int err;
 1894
 1895	rtnl_lock();
 1896	list_del(&nn->list);
 1897	err = __unregister_netdevice_notifier_net(dev_net(dev), nb);
 1898	rtnl_unlock();
 1899	return err;
 1900}
 1901EXPORT_SYMBOL(unregister_netdevice_notifier_dev_net);
 1902
 1903static void move_netdevice_notifiers_dev_net(struct net_device *dev,
 1904					     struct net *net)
 1905{
 1906	struct netdev_net_notifier *nn;
 1907
 1908	list_for_each_entry(nn, &dev->net_notifier_list, list)
 1909		__move_netdevice_notifier_net(dev_net(dev), net, nn->nb);
 1910}
 1911
 1912/**
 1913 *	call_netdevice_notifiers_info - call all network notifier blocks
 1914 *	@val: value passed unmodified to notifier function
 1915 *	@info: notifier information data
 1916 *
 1917 *	Call all network notifier blocks.  Parameters and return value
 1918 *	are as for raw_notifier_call_chain().
 1919 */
 1920
 1921static int call_netdevice_notifiers_info(unsigned long val,
 1922					 struct netdev_notifier_info *info)
 1923{
 1924	struct net *net = dev_net(info->dev);
 1925	int ret;
 1926
 1927	ASSERT_RTNL();
 1928
 1929	/* Run per-netns notifier block chain first, then run the global one.
 1930	 * Hopefully, one day, the global one is going to be removed after
 1931	 * all notifier block registrators get converted to be per-netns.
 1932	 */
 1933	ret = raw_notifier_call_chain(&net->netdev_chain, val, info);
 1934	if (ret & NOTIFY_STOP_MASK)
 1935		return ret;
 1936	return raw_notifier_call_chain(&netdev_chain, val, info);
 1937}
 1938
 1939/**
 1940 *	call_netdevice_notifiers_info_robust - call per-netns notifier blocks
 1941 *	                                       for and rollback on error
 1942 *	@val_up: value passed unmodified to notifier function
 1943 *	@val_down: value passed unmodified to the notifier function when
 1944 *	           recovering from an error on @val_up
 1945 *	@info: notifier information data
 1946 *
 1947 *	Call all per-netns network notifier blocks, but not notifier blocks on
 1948 *	the global notifier chain. Parameters and return value are as for
 1949 *	raw_notifier_call_chain_robust().
 1950 */
 1951
 1952static int
 1953call_netdevice_notifiers_info_robust(unsigned long val_up,
 1954				     unsigned long val_down,
 1955				     struct netdev_notifier_info *info)
 1956{
 1957	struct net *net = dev_net(info->dev);
 1958
 1959	ASSERT_RTNL();
 1960
 1961	return raw_notifier_call_chain_robust(&net->netdev_chain,
 1962					      val_up, val_down, info);
 1963}
 1964
 1965static int call_netdevice_notifiers_extack(unsigned long val,
 1966					   struct net_device *dev,
 1967					   struct netlink_ext_ack *extack)
 1968{
 1969	struct netdev_notifier_info info = {
 1970		.dev = dev,
 1971		.extack = extack,
 1972	};
 1973
 1974	return call_netdevice_notifiers_info(val, &info);
 1975}
 1976
 1977/**
 1978 *	call_netdevice_notifiers - call all network notifier blocks
 1979 *      @val: value passed unmodified to notifier function
 1980 *      @dev: net_device pointer passed unmodified to notifier function
 1981 *
 1982 *	Call all network notifier blocks.  Parameters and return value
 1983 *	are as for raw_notifier_call_chain().
 1984 */
 1985
 1986int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
 1987{
 1988	return call_netdevice_notifiers_extack(val, dev, NULL);
 
 1989}
 1990EXPORT_SYMBOL(call_netdevice_notifiers);
 1991
 1992/**
 1993 *	call_netdevice_notifiers_mtu - call all network notifier blocks
 1994 *	@val: value passed unmodified to notifier function
 1995 *	@dev: net_device pointer passed unmodified to notifier function
 1996 *	@arg: additional u32 argument passed to the notifier function
 1997 *
 1998 *	Call all network notifier blocks.  Parameters and return value
 1999 *	are as for raw_notifier_call_chain().
 2000 */
 2001static int call_netdevice_notifiers_mtu(unsigned long val,
 2002					struct net_device *dev, u32 arg)
 2003{
 2004	struct netdev_notifier_info_ext info = {
 2005		.info.dev = dev,
 2006		.ext.mtu = arg,
 2007	};
 2008
 2009	BUILD_BUG_ON(offsetof(struct netdev_notifier_info_ext, info) != 0);
 2010
 2011	return call_netdevice_notifiers_info(val, &info.info);
 2012}
 2013
 2014#ifdef CONFIG_NET_INGRESS
 2015static DEFINE_STATIC_KEY_FALSE(ingress_needed_key);
 2016
 2017void net_inc_ingress_queue(void)
 2018{
 2019	static_branch_inc(&ingress_needed_key);
 2020}
 2021EXPORT_SYMBOL_GPL(net_inc_ingress_queue);
 2022
 2023void net_dec_ingress_queue(void)
 2024{
 2025	static_branch_dec(&ingress_needed_key);
 2026}
 2027EXPORT_SYMBOL_GPL(net_dec_ingress_queue);
 2028#endif
 2029
 2030#ifdef CONFIG_NET_EGRESS
 2031static DEFINE_STATIC_KEY_FALSE(egress_needed_key);
 2032
 2033void net_inc_egress_queue(void)
 2034{
 2035	static_branch_inc(&egress_needed_key);
 2036}
 2037EXPORT_SYMBOL_GPL(net_inc_egress_queue);
 2038
 2039void net_dec_egress_queue(void)
 2040{
 2041	static_branch_dec(&egress_needed_key);
 2042}
 2043EXPORT_SYMBOL_GPL(net_dec_egress_queue);
 2044#endif
 2045
 2046DEFINE_STATIC_KEY_FALSE(netstamp_needed_key);
 2047EXPORT_SYMBOL(netstamp_needed_key);
 2048#ifdef CONFIG_JUMP_LABEL
 2049static atomic_t netstamp_needed_deferred;
 2050static atomic_t netstamp_wanted;
 2051static void netstamp_clear(struct work_struct *work)
 2052{
 2053	int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
 2054	int wanted;
 2055
 2056	wanted = atomic_add_return(deferred, &netstamp_wanted);
 2057	if (wanted > 0)
 2058		static_branch_enable(&netstamp_needed_key);
 2059	else
 2060		static_branch_disable(&netstamp_needed_key);
 2061}
 2062static DECLARE_WORK(netstamp_work, netstamp_clear);
 2063#endif
 2064
 2065void net_enable_timestamp(void)
 2066{
 2067#ifdef CONFIG_JUMP_LABEL
 2068	int wanted = atomic_read(&netstamp_wanted);
 2069
 2070	while (wanted > 0) {
 2071		if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted + 1))
 2072			return;
 2073	}
 2074	atomic_inc(&netstamp_needed_deferred);
 2075	schedule_work(&netstamp_work);
 2076#else
 2077	static_branch_inc(&netstamp_needed_key);
 2078#endif
 2079}
 2080EXPORT_SYMBOL(net_enable_timestamp);
 2081
 2082void net_disable_timestamp(void)
 2083{
 2084#ifdef CONFIG_JUMP_LABEL
 2085	int wanted = atomic_read(&netstamp_wanted);
 2086
 2087	while (wanted > 1) {
 2088		if (atomic_try_cmpxchg(&netstamp_wanted, &wanted, wanted - 1))
 2089			return;
 2090	}
 2091	atomic_dec(&netstamp_needed_deferred);
 2092	schedule_work(&netstamp_work);
 2093#else
 2094	static_branch_dec(&netstamp_needed_key);
 2095#endif
 2096}
 2097EXPORT_SYMBOL(net_disable_timestamp);
 2098
 2099static inline void net_timestamp_set(struct sk_buff *skb)
 2100{
 2101	skb->tstamp = 0;
 2102	skb->mono_delivery_time = 0;
 2103	if (static_branch_unlikely(&netstamp_needed_key))
 2104		skb->tstamp = ktime_get_real();
 2105}
 2106
 2107#define net_timestamp_check(COND, SKB)				\
 2108	if (static_branch_unlikely(&netstamp_needed_key)) {	\
 2109		if ((COND) && !(SKB)->tstamp)			\
 2110			(SKB)->tstamp = ktime_get_real();	\
 2111	}							\
 2112
 2113bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb)
 2114{
 2115	return __is_skb_forwardable(dev, skb, true);
 
 2116}
 2117EXPORT_SYMBOL_GPL(is_skb_forwardable);
 2118
 2119static int __dev_forward_skb2(struct net_device *dev, struct sk_buff *skb,
 2120			      bool check_mtu)
 2121{
 2122	int ret = ____dev_forward_skb(dev, skb, check_mtu);
 2123
 2124	if (likely(!ret)) {
 2125		skb->protocol = eth_type_trans(skb, dev);
 2126		skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
 2127	}
 2128
 2129	return ret;
 2130}
 
 2131
 2132int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
 2133{
 2134	return __dev_forward_skb2(dev, skb, true);
 
 
 
 
 2135}
 2136EXPORT_SYMBOL_GPL(__dev_forward_skb);
 2137
 2138/**
 2139 * dev_forward_skb - loopback an skb to another netif
 2140 *
 2141 * @dev: destination network device
 2142 * @skb: buffer to forward
 2143 *
 2144 * return values:
 2145 *	NET_RX_SUCCESS	(no congestion)
 2146 *	NET_RX_DROP     (packet was dropped, but freed)
 2147 *
 2148 * dev_forward_skb can be used for injecting an skb from the
 2149 * start_xmit function of one device into the receive queue
 2150 * of another device.
 2151 *
 2152 * The receiving device may be in another namespace, so
 2153 * we have to clear all information in the skb that could
 2154 * impact namespace isolation.
 2155 */
 2156int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
 2157{
 2158	return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
 2159}
 2160EXPORT_SYMBOL_GPL(dev_forward_skb);
 
 
 
 
 2161
 2162int dev_forward_skb_nomtu(struct net_device *dev, struct sk_buff *skb)
 2163{
 2164	return __dev_forward_skb2(dev, skb, false) ?: netif_rx_internal(skb);
 
 
 
 
 
 
 
 
 
 
 2165}
 
 2166
 2167static inline int deliver_skb(struct sk_buff *skb,
 2168			      struct packet_type *pt_prev,
 2169			      struct net_device *orig_dev)
 2170{
 2171	if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC)))
 2172		return -ENOMEM;
 2173	refcount_inc(&skb->users);
 2174	return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
 2175}
 2176
 2177static inline void deliver_ptype_list_skb(struct sk_buff *skb,
 2178					  struct packet_type **pt,
 2179					  struct net_device *orig_dev,
 2180					  __be16 type,
 2181					  struct list_head *ptype_list)
 2182{
 2183	struct packet_type *ptype, *pt_prev = *pt;
 2184
 2185	list_for_each_entry_rcu(ptype, ptype_list, list) {
 2186		if (ptype->type != type)
 2187			continue;
 2188		if (pt_prev)
 2189			deliver_skb(skb, pt_prev, orig_dev);
 2190		pt_prev = ptype;
 2191	}
 2192	*pt = pt_prev;
 2193}
 2194
 2195static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
 2196{
 2197	if (!ptype->af_packet_priv || !skb->sk)
 2198		return false;
 2199
 2200	if (ptype->id_match)
 2201		return ptype->id_match(ptype, skb->sk);
 2202	else if ((struct sock *)ptype->af_packet_priv == skb->sk)
 2203		return true;
 2204
 2205	return false;
 2206}
 2207
 2208/**
 2209 * dev_nit_active - return true if any network interface taps are in use
 2210 *
 2211 * @dev: network device to check for the presence of taps
 2212 */
 2213bool dev_nit_active(struct net_device *dev)
 2214{
 2215	return !list_empty(&ptype_all) || !list_empty(&dev->ptype_all);
 2216}
 2217EXPORT_SYMBOL_GPL(dev_nit_active);
 2218
 2219/*
 2220 *	Support routine. Sends outgoing frames to any network
 2221 *	taps currently in use.
 2222 */
 2223
 2224void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
 2225{
 2226	struct packet_type *ptype;
 2227	struct sk_buff *skb2 = NULL;
 2228	struct packet_type *pt_prev = NULL;
 2229	struct list_head *ptype_list = &ptype_all;
 2230
 2231	rcu_read_lock();
 2232again:
 2233	list_for_each_entry_rcu(ptype, ptype_list, list) {
 2234		if (ptype->ignore_outgoing)
 2235			continue;
 2236
 2237		/* Never send packets back to the socket
 2238		 * they originated from - MvS (miquels@drinkel.ow.org)
 2239		 */
 2240		if (skb_loop_sk(ptype, skb))
 2241			continue;
 
 
 
 
 
 
 2242
 2243		if (pt_prev) {
 2244			deliver_skb(skb2, pt_prev, skb->dev);
 2245			pt_prev = ptype;
 2246			continue;
 2247		}
 2248
 2249		/* need to clone skb, done only once */
 2250		skb2 = skb_clone(skb, GFP_ATOMIC);
 2251		if (!skb2)
 2252			goto out_unlock;
 2253
 2254		net_timestamp_set(skb2);
 2255
 2256		/* skb->nh should be correctly
 2257		 * set by sender, so that the second statement is
 2258		 * just protection against buggy protocols.
 2259		 */
 2260		skb_reset_mac_header(skb2);
 2261
 2262		if (skb_network_header(skb2) < skb2->data ||
 2263		    skb_network_header(skb2) > skb_tail_pointer(skb2)) {
 2264			net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
 2265					     ntohs(skb2->protocol),
 2266					     dev->name);
 2267			skb_reset_network_header(skb2);
 2268		}
 2269
 2270		skb2->transport_header = skb2->network_header;
 2271		skb2->pkt_type = PACKET_OUTGOING;
 2272		pt_prev = ptype;
 2273	}
 
 
 
 
 
 2274
 2275	if (ptype_list == &ptype_all) {
 2276		ptype_list = &dev->ptype_all;
 2277		goto again;
 2278	}
 2279out_unlock:
 2280	if (pt_prev) {
 2281		if (!skb_orphan_frags_rx(skb2, GFP_ATOMIC))
 2282			pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
 2283		else
 2284			kfree_skb(skb2);
 2285	}
 
 
 2286	rcu_read_unlock();
 2287}
 2288EXPORT_SYMBOL_GPL(dev_queue_xmit_nit);
 2289
 2290/**
 2291 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
 2292 * @dev: Network device
 2293 * @txq: number of queues available
 2294 *
 2295 * If real_num_tx_queues is changed the tc mappings may no longer be
 2296 * valid. To resolve this verify the tc mapping remains valid and if
 2297 * not NULL the mapping. With no priorities mapping to this
 2298 * offset/count pair it will no longer be used. In the worst case TC0
 2299 * is invalid nothing can be done so disable priority mappings. If is
 2300 * expected that drivers will fix this mapping if they can before
 2301 * calling netif_set_real_num_tx_queues.
 2302 */
 2303static void netif_setup_tc(struct net_device *dev, unsigned int txq)
 2304{
 2305	int i;
 2306	struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
 2307
 2308	/* If TC0 is invalidated disable TC mapping */
 2309	if (tc->offset + tc->count > txq) {
 2310		netdev_warn(dev, "Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
 
 
 2311		dev->num_tc = 0;
 2312		return;
 2313	}
 2314
 2315	/* Invalidated prio to tc mappings set to TC0 */
 2316	for (i = 1; i < TC_BITMASK + 1; i++) {
 2317		int q = netdev_get_prio_tc_map(dev, i);
 2318
 2319		tc = &dev->tc_to_txq[q];
 2320		if (tc->offset + tc->count > txq) {
 2321			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",
 2322				    i, q);
 
 
 
 2323			netdev_set_prio_tc_map(dev, i, 0);
 2324		}
 2325	}
 2326}
 2327
 2328int netdev_txq_to_tc(struct net_device *dev, unsigned int txq)
 2329{
 2330	if (dev->num_tc) {
 2331		struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
 2332		int i;
 2333
 2334		/* walk through the TCs and see if it falls into any of them */
 2335		for (i = 0; i < TC_MAX_QUEUE; i++, tc++) {
 2336			if ((txq - tc->offset) < tc->count)
 2337				return i;
 2338		}
 2339
 2340		/* didn't find it, just return -1 to indicate no match */
 2341		return -1;
 2342	}
 2343
 2344	return 0;
 2345}
 2346EXPORT_SYMBOL(netdev_txq_to_tc);
 2347
 2348#ifdef CONFIG_XPS
 2349static struct static_key xps_needed __read_mostly;
 2350static struct static_key xps_rxqs_needed __read_mostly;
 2351static DEFINE_MUTEX(xps_map_mutex);
 2352#define xmap_dereference(P)		\
 2353	rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
 2354
 2355static bool remove_xps_queue(struct xps_dev_maps *dev_maps,
 2356			     struct xps_dev_maps *old_maps, int tci, u16 index)
 2357{
 2358	struct xps_map *map = NULL;
 2359	int pos;
 2360
 2361	if (dev_maps)
 2362		map = xmap_dereference(dev_maps->attr_map[tci]);
 2363	if (!map)
 2364		return false;
 2365
 2366	for (pos = map->len; pos--;) {
 2367		if (map->queues[pos] != index)
 2368			continue;
 2369
 2370		if (map->len > 1) {
 2371			map->queues[pos] = map->queues[--map->len];
 2372			break;
 2373		}
 2374
 2375		if (old_maps)
 2376			RCU_INIT_POINTER(old_maps->attr_map[tci], NULL);
 2377		RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL);
 2378		kfree_rcu(map, rcu);
 2379		return false;
 2380	}
 2381
 2382	return true;
 2383}
 2384
 2385static bool remove_xps_queue_cpu(struct net_device *dev,
 2386				 struct xps_dev_maps *dev_maps,
 2387				 int cpu, u16 offset, u16 count)
 2388{
 2389	int num_tc = dev_maps->num_tc;
 2390	bool active = false;
 2391	int tci;
 2392
 2393	for (tci = cpu * num_tc; num_tc--; tci++) {
 2394		int i, j;
 2395
 2396		for (i = count, j = offset; i--; j++) {
 2397			if (!remove_xps_queue(dev_maps, NULL, tci, j))
 2398				break;
 2399		}
 2400
 2401		active |= i < 0;
 2402	}
 2403
 2404	return active;
 2405}
 2406
 2407static void reset_xps_maps(struct net_device *dev,
 2408			   struct xps_dev_maps *dev_maps,
 2409			   enum xps_map_type type)
 2410{
 2411	static_key_slow_dec_cpuslocked(&xps_needed);
 2412	if (type == XPS_RXQS)
 2413		static_key_slow_dec_cpuslocked(&xps_rxqs_needed);
 2414
 2415	RCU_INIT_POINTER(dev->xps_maps[type], NULL);
 2416
 2417	kfree_rcu(dev_maps, rcu);
 2418}
 2419
 2420static void clean_xps_maps(struct net_device *dev, enum xps_map_type type,
 2421			   u16 offset, u16 count)
 2422{
 2423	struct xps_dev_maps *dev_maps;
 2424	bool active = false;
 2425	int i, j;
 2426
 2427	dev_maps = xmap_dereference(dev->xps_maps[type]);
 2428	if (!dev_maps)
 2429		return;
 2430
 2431	for (j = 0; j < dev_maps->nr_ids; j++)
 2432		active |= remove_xps_queue_cpu(dev, dev_maps, j, offset, count);
 2433	if (!active)
 2434		reset_xps_maps(dev, dev_maps, type);
 2435
 2436	if (type == XPS_CPUS) {
 2437		for (i = offset + (count - 1); count--; i--)
 2438			netdev_queue_numa_node_write(
 2439				netdev_get_tx_queue(dev, i), NUMA_NO_NODE);
 2440	}
 2441}
 2442
 2443static void netif_reset_xps_queues(struct net_device *dev, u16 offset,
 2444				   u16 count)
 2445{
 2446	if (!static_key_false(&xps_needed))
 2447		return;
 2448
 2449	cpus_read_lock();
 2450	mutex_lock(&xps_map_mutex);
 2451
 2452	if (static_key_false(&xps_rxqs_needed))
 2453		clean_xps_maps(dev, XPS_RXQS, offset, count);
 2454
 2455	clean_xps_maps(dev, XPS_CPUS, offset, count);
 2456
 2457	mutex_unlock(&xps_map_mutex);
 2458	cpus_read_unlock();
 2459}
 2460
 2461static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
 2462{
 2463	netif_reset_xps_queues(dev, index, dev->num_tx_queues - index);
 2464}
 2465
 2466static struct xps_map *expand_xps_map(struct xps_map *map, int attr_index,
 2467				      u16 index, bool is_rxqs_map)
 2468{
 2469	struct xps_map *new_map;
 2470	int alloc_len = XPS_MIN_MAP_ALLOC;
 2471	int i, pos;
 2472
 2473	for (pos = 0; map && pos < map->len; pos++) {
 2474		if (map->queues[pos] != index)
 2475			continue;
 2476		return map;
 2477	}
 2478
 2479	/* Need to add tx-queue to this CPU's/rx-queue's existing map */
 2480	if (map) {
 2481		if (pos < map->alloc_len)
 2482			return map;
 2483
 2484		alloc_len = map->alloc_len * 2;
 2485	}
 2486
 2487	/* Need to allocate new map to store tx-queue on this CPU's/rx-queue's
 2488	 *  map
 2489	 */
 2490	if (is_rxqs_map)
 2491		new_map = kzalloc(XPS_MAP_SIZE(alloc_len), GFP_KERNEL);
 2492	else
 2493		new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
 2494				       cpu_to_node(attr_index));
 2495	if (!new_map)
 2496		return NULL;
 2497
 2498	for (i = 0; i < pos; i++)
 2499		new_map->queues[i] = map->queues[i];
 2500	new_map->alloc_len = alloc_len;
 2501	new_map->len = pos;
 2502
 2503	return new_map;
 2504}
 2505
 2506/* Copy xps maps at a given index */
 2507static void xps_copy_dev_maps(struct xps_dev_maps *dev_maps,
 2508			      struct xps_dev_maps *new_dev_maps, int index,
 2509			      int tc, bool skip_tc)
 2510{
 2511	int i, tci = index * dev_maps->num_tc;
 2512	struct xps_map *map;
 2513
 2514	/* copy maps belonging to foreign traffic classes */
 2515	for (i = 0; i < dev_maps->num_tc; i++, tci++) {
 2516		if (i == tc && skip_tc)
 2517			continue;
 2518
 2519		/* fill in the new device map from the old device map */
 2520		map = xmap_dereference(dev_maps->attr_map[tci]);
 2521		RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);
 2522	}
 2523}
 2524
 2525/* Must be called under cpus_read_lock */
 2526int __netif_set_xps_queue(struct net_device *dev, const unsigned long *mask,
 2527			  u16 index, enum xps_map_type type)
 2528{
 2529	struct xps_dev_maps *dev_maps, *new_dev_maps = NULL, *old_dev_maps = NULL;
 2530	const unsigned long *online_mask = NULL;
 2531	bool active = false, copy = false;
 2532	int i, j, tci, numa_node_id = -2;
 2533	int maps_sz, num_tc = 1, tc = 0;
 2534	struct xps_map *map, *new_map;
 2535	unsigned int nr_ids;
 2536
 2537	if (dev->num_tc) {
 2538		/* Do not allow XPS on subordinate device directly */
 2539		num_tc = dev->num_tc;
 2540		if (num_tc < 0)
 2541			return -EINVAL;
 2542
 2543		/* If queue belongs to subordinate dev use its map */
 2544		dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev;
 2545
 2546		tc = netdev_txq_to_tc(dev, index);
 2547		if (tc < 0)
 2548			return -EINVAL;
 2549	}
 2550
 2551	mutex_lock(&xps_map_mutex);
 2552
 2553	dev_maps = xmap_dereference(dev->xps_maps[type]);
 2554	if (type == XPS_RXQS) {
 2555		maps_sz = XPS_RXQ_DEV_MAPS_SIZE(num_tc, dev->num_rx_queues);
 2556		nr_ids = dev->num_rx_queues;
 2557	} else {
 2558		maps_sz = XPS_CPU_DEV_MAPS_SIZE(num_tc);
 2559		if (num_possible_cpus() > 1)
 2560			online_mask = cpumask_bits(cpu_online_mask);
 2561		nr_ids = nr_cpu_ids;
 2562	}
 2563
 2564	if (maps_sz < L1_CACHE_BYTES)
 2565		maps_sz = L1_CACHE_BYTES;
 2566
 2567	/* The old dev_maps could be larger or smaller than the one we're
 2568	 * setting up now, as dev->num_tc or nr_ids could have been updated in
 2569	 * between. We could try to be smart, but let's be safe instead and only
 2570	 * copy foreign traffic classes if the two map sizes match.
 2571	 */
 2572	if (dev_maps &&
 2573	    dev_maps->num_tc == num_tc && dev_maps->nr_ids == nr_ids)
 2574		copy = true;
 2575
 2576	/* allocate memory for queue storage */
 2577	for (j = -1; j = netif_attrmask_next_and(j, online_mask, mask, nr_ids),
 2578	     j < nr_ids;) {
 2579		if (!new_dev_maps) {
 2580			new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
 2581			if (!new_dev_maps) {
 2582				mutex_unlock(&xps_map_mutex);
 2583				return -ENOMEM;
 2584			}
 2585
 2586			new_dev_maps->nr_ids = nr_ids;
 2587			new_dev_maps->num_tc = num_tc;
 2588		}
 2589
 2590		tci = j * num_tc + tc;
 2591		map = copy ? xmap_dereference(dev_maps->attr_map[tci]) : NULL;
 2592
 2593		map = expand_xps_map(map, j, index, type == XPS_RXQS);
 2594		if (!map)
 2595			goto error;
 2596
 2597		RCU_INIT_POINTER(new_dev_maps->attr_map[tci], map);
 2598	}
 2599
 2600	if (!new_dev_maps)
 2601		goto out_no_new_maps;
 2602
 2603	if (!dev_maps) {
 2604		/* Increment static keys at most once per type */
 2605		static_key_slow_inc_cpuslocked(&xps_needed);
 2606		if (type == XPS_RXQS)
 2607			static_key_slow_inc_cpuslocked(&xps_rxqs_needed);
 2608	}
 2609
 2610	for (j = 0; j < nr_ids; j++) {
 2611		bool skip_tc = false;
 2612
 2613		tci = j * num_tc + tc;
 2614		if (netif_attr_test_mask(j, mask, nr_ids) &&
 2615		    netif_attr_test_online(j, online_mask, nr_ids)) {
 2616			/* add tx-queue to CPU/rx-queue maps */
 2617			int pos = 0;
 2618
 2619			skip_tc = true;
 2620
 2621			map = xmap_dereference(new_dev_maps->attr_map[tci]);
 2622			while ((pos < map->len) && (map->queues[pos] != index))
 2623				pos++;
 2624
 2625			if (pos == map->len)
 2626				map->queues[map->len++] = index;
 2627#ifdef CONFIG_NUMA
 2628			if (type == XPS_CPUS) {
 2629				if (numa_node_id == -2)
 2630					numa_node_id = cpu_to_node(j);
 2631				else if (numa_node_id != cpu_to_node(j))
 2632					numa_node_id = -1;
 2633			}
 2634#endif
 2635		}
 2636
 2637		if (copy)
 2638			xps_copy_dev_maps(dev_maps, new_dev_maps, j, tc,
 2639					  skip_tc);
 2640	}
 2641
 2642	rcu_assign_pointer(dev->xps_maps[type], new_dev_maps);
 2643
 2644	/* Cleanup old maps */
 2645	if (!dev_maps)
 2646		goto out_no_old_maps;
 2647
 2648	for (j = 0; j < dev_maps->nr_ids; j++) {
 2649		for (i = num_tc, tci = j * dev_maps->num_tc; i--; tci++) {
 2650			map = xmap_dereference(dev_maps->attr_map[tci]);
 2651			if (!map)
 2652				continue;
 2653
 2654			if (copy) {
 2655				new_map = xmap_dereference(new_dev_maps->attr_map[tci]);
 2656				if (map == new_map)
 2657					continue;
 2658			}
 2659
 2660			RCU_INIT_POINTER(dev_maps->attr_map[tci], NULL);
 2661			kfree_rcu(map, rcu);
 2662		}
 2663	}
 2664
 2665	old_dev_maps = dev_maps;
 2666
 2667out_no_old_maps:
 2668	dev_maps = new_dev_maps;
 2669	active = true;
 2670
 2671out_no_new_maps:
 2672	if (type == XPS_CPUS)
 2673		/* update Tx queue numa node */
 2674		netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
 2675					     (numa_node_id >= 0) ?
 2676					     numa_node_id : NUMA_NO_NODE);
 2677
 2678	if (!dev_maps)
 2679		goto out_no_maps;
 2680
 2681	/* removes tx-queue from unused CPUs/rx-queues */
 2682	for (j = 0; j < dev_maps->nr_ids; j++) {
 2683		tci = j * dev_maps->num_tc;
 2684
 2685		for (i = 0; i < dev_maps->num_tc; i++, tci++) {
 2686			if (i == tc &&
 2687			    netif_attr_test_mask(j, mask, dev_maps->nr_ids) &&
 2688			    netif_attr_test_online(j, online_mask, dev_maps->nr_ids))
 2689				continue;
 2690
 2691			active |= remove_xps_queue(dev_maps,
 2692						   copy ? old_dev_maps : NULL,
 2693						   tci, index);
 2694		}
 2695	}
 2696
 2697	if (old_dev_maps)
 2698		kfree_rcu(old_dev_maps, rcu);
 2699
 2700	/* free map if not active */
 2701	if (!active)
 2702		reset_xps_maps(dev, dev_maps, type);
 2703
 2704out_no_maps:
 2705	mutex_unlock(&xps_map_mutex);
 2706
 2707	return 0;
 2708error:
 2709	/* remove any maps that we added */
 2710	for (j = 0; j < nr_ids; j++) {
 2711		for (i = num_tc, tci = j * num_tc; i--; tci++) {
 2712			new_map = xmap_dereference(new_dev_maps->attr_map[tci]);
 2713			map = copy ?
 2714			      xmap_dereference(dev_maps->attr_map[tci]) :
 2715			      NULL;
 2716			if (new_map && new_map != map)
 2717				kfree(new_map);
 2718		}
 2719	}
 2720
 2721	mutex_unlock(&xps_map_mutex);
 2722
 2723	kfree(new_dev_maps);
 2724	return -ENOMEM;
 2725}
 2726EXPORT_SYMBOL_GPL(__netif_set_xps_queue);
 2727
 2728int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
 2729			u16 index)
 2730{
 2731	int ret;
 2732
 2733	cpus_read_lock();
 2734	ret =  __netif_set_xps_queue(dev, cpumask_bits(mask), index, XPS_CPUS);
 2735	cpus_read_unlock();
 2736
 2737	return ret;
 2738}
 2739EXPORT_SYMBOL(netif_set_xps_queue);
 2740
 2741#endif
 2742static void netdev_unbind_all_sb_channels(struct net_device *dev)
 2743{
 2744	struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues];
 2745
 2746	/* Unbind any subordinate channels */
 2747	while (txq-- != &dev->_tx[0]) {
 2748		if (txq->sb_dev)
 2749			netdev_unbind_sb_channel(dev, txq->sb_dev);
 2750	}
 2751}
 2752
 2753void netdev_reset_tc(struct net_device *dev)
 2754{
 2755#ifdef CONFIG_XPS
 2756	netif_reset_xps_queues_gt(dev, 0);
 2757#endif
 2758	netdev_unbind_all_sb_channels(dev);
 2759
 2760	/* Reset TC configuration of device */
 2761	dev->num_tc = 0;
 2762	memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq));
 2763	memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map));
 2764}
 2765EXPORT_SYMBOL(netdev_reset_tc);
 2766
 2767int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset)
 2768{
 2769	if (tc >= dev->num_tc)
 2770		return -EINVAL;
 2771
 2772#ifdef CONFIG_XPS
 2773	netif_reset_xps_queues(dev, offset, count);
 2774#endif
 2775	dev->tc_to_txq[tc].count = count;
 2776	dev->tc_to_txq[tc].offset = offset;
 2777	return 0;
 2778}
 2779EXPORT_SYMBOL(netdev_set_tc_queue);
 2780
 2781int netdev_set_num_tc(struct net_device *dev, u8 num_tc)
 2782{
 2783	if (num_tc > TC_MAX_QUEUE)
 2784		return -EINVAL;
 2785
 2786#ifdef CONFIG_XPS
 2787	netif_reset_xps_queues_gt(dev, 0);
 2788#endif
 2789	netdev_unbind_all_sb_channels(dev);
 2790
 2791	dev->num_tc = num_tc;
 2792	return 0;
 2793}
 2794EXPORT_SYMBOL(netdev_set_num_tc);
 2795
 2796void netdev_unbind_sb_channel(struct net_device *dev,
 2797			      struct net_device *sb_dev)
 2798{
 2799	struct netdev_queue *txq = &dev->_tx[dev->num_tx_queues];
 2800
 2801#ifdef CONFIG_XPS
 2802	netif_reset_xps_queues_gt(sb_dev, 0);
 2803#endif
 2804	memset(sb_dev->tc_to_txq, 0, sizeof(sb_dev->tc_to_txq));
 2805	memset(sb_dev->prio_tc_map, 0, sizeof(sb_dev->prio_tc_map));
 2806
 2807	while (txq-- != &dev->_tx[0]) {
 2808		if (txq->sb_dev == sb_dev)
 2809			txq->sb_dev = NULL;
 2810	}
 2811}
 2812EXPORT_SYMBOL(netdev_unbind_sb_channel);
 2813
 2814int netdev_bind_sb_channel_queue(struct net_device *dev,
 2815				 struct net_device *sb_dev,
 2816				 u8 tc, u16 count, u16 offset)
 2817{
 2818	/* Make certain the sb_dev and dev are already configured */
 2819	if (sb_dev->num_tc >= 0 || tc >= dev->num_tc)
 2820		return -EINVAL;
 2821
 2822	/* We cannot hand out queues we don't have */
 2823	if ((offset + count) > dev->real_num_tx_queues)
 2824		return -EINVAL;
 2825
 2826	/* Record the mapping */
 2827	sb_dev->tc_to_txq[tc].count = count;
 2828	sb_dev->tc_to_txq[tc].offset = offset;
 2829
 2830	/* Provide a way for Tx queue to find the tc_to_txq map or
 2831	 * XPS map for itself.
 2832	 */
 2833	while (count--)
 2834		netdev_get_tx_queue(dev, count + offset)->sb_dev = sb_dev;
 2835
 2836	return 0;
 2837}
 2838EXPORT_SYMBOL(netdev_bind_sb_channel_queue);
 2839
 2840int netdev_set_sb_channel(struct net_device *dev, u16 channel)
 2841{
 2842	/* Do not use a multiqueue device to represent a subordinate channel */
 2843	if (netif_is_multiqueue(dev))
 2844		return -ENODEV;
 2845
 2846	/* We allow channels 1 - 32767 to be used for subordinate channels.
 2847	 * Channel 0 is meant to be "native" mode and used only to represent
 2848	 * the main root device. We allow writing 0 to reset the device back
 2849	 * to normal mode after being used as a subordinate channel.
 2850	 */
 2851	if (channel > S16_MAX)
 2852		return -EINVAL;
 2853
 2854	dev->num_tc = -channel;
 2855
 2856	return 0;
 2857}
 2858EXPORT_SYMBOL(netdev_set_sb_channel);
 2859
 2860/*
 2861 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
 2862 * greater than real_num_tx_queues stale skbs on the qdisc must be flushed.
 2863 */
 2864int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
 2865{
 2866	bool disabling;
 2867	int rc;
 2868
 2869	disabling = txq < dev->real_num_tx_queues;
 2870
 2871	if (txq < 1 || txq > dev->num_tx_queues)
 2872		return -EINVAL;
 2873
 2874	if (dev->reg_state == NETREG_REGISTERED ||
 2875	    dev->reg_state == NETREG_UNREGISTERING) {
 2876		ASSERT_RTNL();
 2877
 2878		rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
 2879						  txq);
 2880		if (rc)
 2881			return rc;
 2882
 2883		if (dev->num_tc)
 2884			netif_setup_tc(dev, txq);
 2885
 2886		dev_qdisc_change_real_num_tx(dev, txq);
 2887
 2888		dev->real_num_tx_queues = txq;
 2889
 2890		if (disabling) {
 2891			synchronize_net();
 2892			qdisc_reset_all_tx_gt(dev, txq);
 2893#ifdef CONFIG_XPS
 2894			netif_reset_xps_queues_gt(dev, txq);
 2895#endif
 2896		}
 2897	} else {
 2898		dev->real_num_tx_queues = txq;
 2899	}
 2900
 
 2901	return 0;
 2902}
 2903EXPORT_SYMBOL(netif_set_real_num_tx_queues);
 2904
 2905#ifdef CONFIG_SYSFS
 2906/**
 2907 *	netif_set_real_num_rx_queues - set actual number of RX queues used
 2908 *	@dev: Network device
 2909 *	@rxq: Actual number of RX queues
 2910 *
 2911 *	This must be called either with the rtnl_lock held or before
 2912 *	registration of the net device.  Returns 0 on success, or a
 2913 *	negative error code.  If called before registration, it always
 2914 *	succeeds.
 2915 */
 2916int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
 2917{
 2918	int rc;
 2919
 2920	if (rxq < 1 || rxq > dev->num_rx_queues)
 2921		return -EINVAL;
 2922
 2923	if (dev->reg_state == NETREG_REGISTERED) {
 2924		ASSERT_RTNL();
 2925
 2926		rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
 2927						  rxq);
 2928		if (rc)
 2929			return rc;
 2930	}
 2931
 2932	dev->real_num_rx_queues = rxq;
 2933	return 0;
 2934}
 2935EXPORT_SYMBOL(netif_set_real_num_rx_queues);
 2936#endif
 2937
 2938/**
 2939 *	netif_set_real_num_queues - set actual number of RX and TX queues used
 2940 *	@dev: Network device
 2941 *	@txq: Actual number of TX queues
 2942 *	@rxq: Actual number of RX queues
 2943 *
 2944 *	Set the real number of both TX and RX queues.
 2945 *	Does nothing if the number of queues is already correct.
 2946 */
 2947int netif_set_real_num_queues(struct net_device *dev,
 2948			      unsigned int txq, unsigned int rxq)
 2949{
 2950	unsigned int old_rxq = dev->real_num_rx_queues;
 2951	int err;
 2952
 2953	if (txq < 1 || txq > dev->num_tx_queues ||
 2954	    rxq < 1 || rxq > dev->num_rx_queues)
 2955		return -EINVAL;
 2956
 2957	/* Start from increases, so the error path only does decreases -
 2958	 * decreases can't fail.
 2959	 */
 2960	if (rxq > dev->real_num_rx_queues) {
 2961		err = netif_set_real_num_rx_queues(dev, rxq);
 2962		if (err)
 2963			return err;
 2964	}
 2965	if (txq > dev->real_num_tx_queues) {
 2966		err = netif_set_real_num_tx_queues(dev, txq);
 2967		if (err)
 2968			goto undo_rx;
 2969	}
 2970	if (rxq < dev->real_num_rx_queues)
 2971		WARN_ON(netif_set_real_num_rx_queues(dev, rxq));
 2972	if (txq < dev->real_num_tx_queues)
 2973		WARN_ON(netif_set_real_num_tx_queues(dev, txq));
 2974
 2975	return 0;
 2976undo_rx:
 2977	WARN_ON(netif_set_real_num_rx_queues(dev, old_rxq));
 2978	return err;
 2979}
 2980EXPORT_SYMBOL(netif_set_real_num_queues);
 2981
 2982/**
 2983 * netif_set_tso_max_size() - set the max size of TSO frames supported
 2984 * @dev:	netdev to update
 2985 * @size:	max skb->len of a TSO frame
 2986 *
 2987 * Set the limit on the size of TSO super-frames the device can handle.
 2988 * Unless explicitly set the stack will assume the value of
 2989 * %GSO_LEGACY_MAX_SIZE.
 2990 */
 2991void netif_set_tso_max_size(struct net_device *dev, unsigned int size)
 2992{
 2993	dev->tso_max_size = min(GSO_MAX_SIZE, size);
 2994	if (size < READ_ONCE(dev->gso_max_size))
 2995		netif_set_gso_max_size(dev, size);
 2996}
 2997EXPORT_SYMBOL(netif_set_tso_max_size);
 2998
 2999/**
 3000 * netif_set_tso_max_segs() - set the max number of segs supported for TSO
 3001 * @dev:	netdev to update
 3002 * @segs:	max number of TCP segments
 3003 *
 3004 * Set the limit on the number of TCP segments the device can generate from
 3005 * a single TSO super-frame.
 3006 * Unless explicitly set the stack will assume the value of %GSO_MAX_SEGS.
 3007 */
 3008void netif_set_tso_max_segs(struct net_device *dev, unsigned int segs)
 3009{
 3010	dev->tso_max_segs = segs;
 3011	if (segs < READ_ONCE(dev->gso_max_segs))
 3012		netif_set_gso_max_segs(dev, segs);
 3013}
 3014EXPORT_SYMBOL(netif_set_tso_max_segs);
 3015
 3016/**
 3017 * netif_inherit_tso_max() - copy all TSO limits from a lower device to an upper
 3018 * @to:		netdev to update
 3019 * @from:	netdev from which to copy the limits
 3020 */
 3021void netif_inherit_tso_max(struct net_device *to, const struct net_device *from)
 3022{
 3023	netif_set_tso_max_size(to, from->tso_max_size);
 3024	netif_set_tso_max_segs(to, from->tso_max_segs);
 3025}
 3026EXPORT_SYMBOL(netif_inherit_tso_max);
 3027
 3028/**
 3029 * netif_get_num_default_rss_queues - default number of RSS queues
 3030 *
 3031 * Default value is the number of physical cores if there are only 1 or 2, or
 3032 * divided by 2 if there are more.
 3033 */
 3034int netif_get_num_default_rss_queues(void)
 3035{
 3036	cpumask_var_t cpus;
 3037	int cpu, count = 0;
 3038
 3039	if (unlikely(is_kdump_kernel() || !zalloc_cpumask_var(&cpus, GFP_KERNEL)))
 3040		return 1;
 3041
 3042	cpumask_copy(cpus, cpu_online_mask);
 3043	for_each_cpu(cpu, cpus) {
 3044		++count;
 3045		cpumask_andnot(cpus, cpus, topology_sibling_cpumask(cpu));
 3046	}
 3047	free_cpumask_var(cpus);
 3048
 3049	return count > 2 ? DIV_ROUND_UP(count, 2) : count;
 3050}
 3051EXPORT_SYMBOL(netif_get_num_default_rss_queues);
 3052
 3053static void __netif_reschedule(struct Qdisc *q)
 3054{
 3055	struct softnet_data *sd;
 3056	unsigned long flags;
 3057
 3058	local_irq_save(flags);
 3059	sd = this_cpu_ptr(&softnet_data);
 3060	q->next_sched = NULL;
 3061	*sd->output_queue_tailp = q;
 3062	sd->output_queue_tailp = &q->next_sched;
 3063	raise_softirq_irqoff(NET_TX_SOFTIRQ);
 3064	local_irq_restore(flags);
 3065}
 3066
 3067void __netif_schedule(struct Qdisc *q)
 3068{
 3069	if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
 3070		__netif_reschedule(q);
 3071}
 3072EXPORT_SYMBOL(__netif_schedule);
 3073
 3074struct dev_kfree_skb_cb {
 3075	enum skb_free_reason reason;
 3076};
 3077
 3078static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
 3079{
 3080	return (struct dev_kfree_skb_cb *)skb->cb;
 3081}
 3082
 3083void netif_schedule_queue(struct netdev_queue *txq)
 3084{
 3085	rcu_read_lock();
 3086	if (!netif_xmit_stopped(txq)) {
 3087		struct Qdisc *q = rcu_dereference(txq->qdisc);
 3088
 3089		__netif_schedule(q);
 3090	}
 3091	rcu_read_unlock();
 3092}
 3093EXPORT_SYMBOL(netif_schedule_queue);
 3094
 3095void netif_tx_wake_queue(struct netdev_queue *dev_queue)
 3096{
 3097	if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) {
 3098		struct Qdisc *q;
 3099
 3100		rcu_read_lock();
 3101		q = rcu_dereference(dev_queue->qdisc);
 3102		__netif_schedule(q);
 3103		rcu_read_unlock();
 3104	}
 3105}
 3106EXPORT_SYMBOL(netif_tx_wake_queue);
 3107
 3108void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
 3109{
 3110	unsigned long flags;
 
 
 3111
 3112	if (unlikely(!skb))
 3113		return;
 3114
 3115	if (likely(refcount_read(&skb->users) == 1)) {
 3116		smp_rmb();
 3117		refcount_set(&skb->users, 0);
 3118	} else if (likely(!refcount_dec_and_test(&skb->users))) {
 3119		return;
 3120	}
 3121	get_kfree_skb_cb(skb)->reason = reason;
 3122	local_irq_save(flags);
 3123	skb->next = __this_cpu_read(softnet_data.completion_queue);
 3124	__this_cpu_write(softnet_data.completion_queue, skb);
 3125	raise_softirq_irqoff(NET_TX_SOFTIRQ);
 3126	local_irq_restore(flags);
 3127}
 3128EXPORT_SYMBOL(__dev_kfree_skb_irq);
 3129
 3130void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
 3131{
 3132	if (in_hardirq() || irqs_disabled())
 3133		__dev_kfree_skb_irq(skb, reason);
 3134	else
 3135		dev_kfree_skb(skb);
 3136}
 3137EXPORT_SYMBOL(__dev_kfree_skb_any);
 3138
 3139
 3140/**
 3141 * netif_device_detach - mark device as removed
 3142 * @dev: network device
 3143 *
 3144 * Mark device as removed from system and therefore no longer available.
 3145 */
 3146void netif_device_detach(struct net_device *dev)
 3147{
 3148	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
 3149	    netif_running(dev)) {
 3150		netif_tx_stop_all_queues(dev);
 3151	}
 3152}
 3153EXPORT_SYMBOL(netif_device_detach);
 3154
 3155/**
 3156 * netif_device_attach - mark device as attached
 3157 * @dev: network device
 3158 *
 3159 * Mark device as attached from system and restart if needed.
 3160 */
 3161void netif_device_attach(struct net_device *dev)
 3162{
 3163	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
 3164	    netif_running(dev)) {
 3165		netif_tx_wake_all_queues(dev);
 3166		__netdev_watchdog_up(dev);
 3167	}
 3168}
 3169EXPORT_SYMBOL(netif_device_attach);
 3170
 3171/*
 3172 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
 3173 * to be used as a distribution range.
 3174 */
 3175static u16 skb_tx_hash(const struct net_device *dev,
 3176		       const struct net_device *sb_dev,
 3177		       struct sk_buff *skb)
 3178{
 3179	u32 hash;
 3180	u16 qoffset = 0;
 3181	u16 qcount = dev->real_num_tx_queues;
 3182
 3183	if (dev->num_tc) {
 3184		u8 tc = netdev_get_prio_tc_map(dev, skb->priority);
 3185
 3186		qoffset = sb_dev->tc_to_txq[tc].offset;
 3187		qcount = sb_dev->tc_to_txq[tc].count;
 3188		if (unlikely(!qcount)) {
 3189			net_warn_ratelimited("%s: invalid qcount, qoffset %u for tc %u\n",
 3190					     sb_dev->name, qoffset, tc);
 3191			qoffset = 0;
 3192			qcount = dev->real_num_tx_queues;
 3193		}
 3194	}
 3195
 3196	if (skb_rx_queue_recorded(skb)) {
 3197		hash = skb_get_rx_queue(skb);
 3198		if (hash >= qoffset)
 3199			hash -= qoffset;
 3200		while (unlikely(hash >= qcount))
 3201			hash -= qcount;
 3202		return hash + qoffset;
 3203	}
 3204
 3205	return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset;
 3206}
 3207
 3208static void skb_warn_bad_offload(const struct sk_buff *skb)
 3209{
 3210	static const netdev_features_t null_features;
 3211	struct net_device *dev = skb->dev;
 3212	const char *name = "";
 3213
 3214	if (!net_ratelimit())
 3215		return;
 3216
 3217	if (dev) {
 3218		if (dev->dev.parent)
 3219			name = dev_driver_string(dev->dev.parent);
 3220		else
 3221			name = netdev_name(dev);
 3222	}
 3223	skb_dump(KERN_WARNING, skb, false);
 3224	WARN(1, "%s: caps=(%pNF, %pNF)\n",
 3225	     name, dev ? &dev->features : &null_features,
 3226	     skb->sk ? &skb->sk->sk_route_caps : &null_features);
 3227}
 
 
 3228
 3229/*
 3230 * Invalidate hardware checksum when packet is to be mangled, and
 3231 * complete checksum manually on outgoing path.
 3232 */
 3233int skb_checksum_help(struct sk_buff *skb)
 3234{
 3235	__wsum csum;
 3236	int ret = 0, offset;
 3237
 3238	if (skb->ip_summed == CHECKSUM_COMPLETE)
 3239		goto out_set_summed;
 3240
 3241	if (unlikely(skb_is_gso(skb))) {
 3242		skb_warn_bad_offload(skb);
 3243		return -EINVAL;
 3244	}
 3245
 3246	/* Before computing a checksum, we should make sure no frag could
 3247	 * be modified by an external entity : checksum could be wrong.
 3248	 */
 3249	if (skb_has_shared_frag(skb)) {
 3250		ret = __skb_linearize(skb);
 3251		if (ret)
 3252			goto out;
 3253	}
 3254
 3255	offset = skb_checksum_start_offset(skb);
 3256	ret = -EINVAL;
 3257	if (WARN_ON_ONCE(offset >= skb_headlen(skb))) {
 3258		DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false);
 3259		goto out;
 3260	}
 3261	csum = skb_checksum(skb, offset, skb->len - offset, 0);
 3262
 3263	offset += skb->csum_offset;
 3264	if (WARN_ON_ONCE(offset + sizeof(__sum16) > skb_headlen(skb))) {
 3265		DO_ONCE_LITE(skb_dump, KERN_ERR, skb, false);
 3266		goto out;
 3267	}
 3268	ret = skb_ensure_writable(skb, offset + sizeof(__sum16));
 3269	if (ret)
 3270		goto out;
 3271
 3272	*(__sum16 *)(skb->data + offset) = csum_fold(csum) ?: CSUM_MANGLED_0;
 3273out_set_summed:
 3274	skb->ip_summed = CHECKSUM_NONE;
 3275out:
 3276	return ret;
 3277}
 3278EXPORT_SYMBOL(skb_checksum_help);
 3279
 3280int skb_crc32c_csum_help(struct sk_buff *skb)
 3281{
 3282	__le32 crc32c_csum;
 3283	int ret = 0, offset, start;
 3284
 3285	if (skb->ip_summed != CHECKSUM_PARTIAL)
 3286		goto out;
 3287
 3288	if (unlikely(skb_is_gso(skb)))
 3289		goto out;
 3290
 3291	/* Before computing a checksum, we should make sure no frag could
 3292	 * be modified by an external entity : checksum could be wrong.
 3293	 */
 3294	if (unlikely(skb_has_shared_frag(skb))) {
 3295		ret = __skb_linearize(skb);
 3296		if (ret)
 3297			goto out;
 3298	}
 3299	start = skb_checksum_start_offset(skb);
 3300	offset = start + offsetof(struct sctphdr, checksum);
 3301	if (WARN_ON_ONCE(offset >= skb_headlen(skb))) {
 3302		ret = -EINVAL;
 3303		goto out;
 3304	}
 3305
 3306	ret = skb_ensure_writable(skb, offset + sizeof(__le32));
 3307	if (ret)
 3308		goto out;
 3309
 3310	crc32c_csum = cpu_to_le32(~__skb_checksum(skb, start,
 3311						  skb->len - start, ~(__u32)0,
 3312						  crc32c_csum_stub));
 3313	*(__le32 *)(skb->data + offset) = crc32c_csum;
 3314	skb->ip_summed = CHECKSUM_NONE;
 3315	skb->csum_not_inet = 0;
 3316out:
 3317	return ret;
 3318}
 3319
 3320__be16 skb_network_protocol(struct sk_buff *skb, int *depth)
 3321{
 3322	__be16 type = skb->protocol;
 3323
 3324	/* Tunnel gso handlers can set protocol to ethernet. */
 3325	if (type == htons(ETH_P_TEB)) {
 3326		struct ethhdr *eth;
 3327
 3328		if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
 3329			return 0;
 3330
 3331		eth = (struct ethhdr *)skb->data;
 3332		type = eth->h_proto;
 3333	}
 3334
 3335	return __vlan_get_protocol(skb, type, depth);
 3336}
 3337
 3338/* openvswitch calls this on rx path, so we need a different check.
 3339 */
 3340static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
 3341{
 3342	if (tx_path)
 3343		return skb->ip_summed != CHECKSUM_PARTIAL &&
 3344		       skb->ip_summed != CHECKSUM_UNNECESSARY;
 3345
 3346	return skb->ip_summed == CHECKSUM_NONE;
 3347}
 3348
 3349/**
 3350 *	__skb_gso_segment - Perform segmentation on skb.
 3351 *	@skb: buffer to segment
 3352 *	@features: features for the output path (see dev->features)
 3353 *	@tx_path: whether it is called in TX path
 3354 *
 3355 *	This function segments the given skb and returns a list of segments.
 3356 *
 3357 *	It may return NULL if the skb requires no segmentation.  This is
 3358 *	only possible when GSO is used for verifying header integrity.
 3359 *
 3360 *	Segmentation preserves SKB_GSO_CB_OFFSET bytes of previous skb cb.
 3361 */
 3362struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
 3363				  netdev_features_t features, bool tx_path)
 3364{
 3365	struct sk_buff *segs;
 
 
 
 
 3366
 3367	if (unlikely(skb_needs_check(skb, tx_path))) {
 3368		int err;
 3369
 3370		/* We're going to init ->check field in TCP or UDP header */
 3371		err = skb_cow_head(skb, 0);
 3372		if (err < 0)
 3373			return ERR_PTR(err);
 
 
 3374	}
 3375
 3376	/* Only report GSO partial support if it will enable us to
 3377	 * support segmentation on this frame without needing additional
 3378	 * work.
 3379	 */
 3380	if (features & NETIF_F_GSO_PARTIAL) {
 3381		netdev_features_t partial_features = NETIF_F_GSO_ROBUST;
 3382		struct net_device *dev = skb->dev;
 3383
 3384		partial_features |= dev->features & dev->gso_partial_features;
 3385		if (!skb_gso_ok(skb, features | partial_features))
 3386			features &= ~NETIF_F_GSO_PARTIAL;
 3387	}
 3388
 3389	BUILD_BUG_ON(SKB_GSO_CB_OFFSET +
 3390		     sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb));
 3391
 3392	SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
 3393	SKB_GSO_CB(skb)->encap_level = 0;
 
 
 3394
 3395	skb_reset_mac_header(skb);
 3396	skb_reset_mac_len(skb);
 
 
 3397
 3398	segs = skb_mac_gso_segment(skb, features);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 3399
 3400	if (segs != skb && unlikely(skb_needs_check(skb, tx_path) && !IS_ERR(segs)))
 3401		skb_warn_bad_offload(skb);
 3402
 3403	return segs;
 3404}
 3405EXPORT_SYMBOL(__skb_gso_segment);
 3406
 3407/* Take action when hardware reception checksum errors are detected. */
 3408#ifdef CONFIG_BUG
 3409static void do_netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb)
 3410{
 3411	netdev_err(dev, "hw csum failure\n");
 3412	skb_dump(KERN_ERR, skb, true);
 3413	dump_stack();
 3414}
 3415
 3416void netdev_rx_csum_fault(struct net_device *dev, struct sk_buff *skb)
 3417{
 3418	DO_ONCE_LITE(do_netdev_rx_csum_fault, dev, skb);
 
 
 
 
 3419}
 3420EXPORT_SYMBOL(netdev_rx_csum_fault);
 3421#endif
 3422
 3423/* XXX: check that highmem exists at all on the given machine. */
 
 
 
 
 3424static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
 3425{
 3426#ifdef CONFIG_HIGHMEM
 3427	int i;
 3428
 3429	if (!(dev->features & NETIF_F_HIGHDMA)) {
 3430		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
 3431			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
 
 
 
 
 
 3432
 3433			if (PageHighMem(skb_frag_page(frag)))
 
 
 
 
 3434				return 1;
 3435		}
 3436	}
 3437#endif
 3438	return 0;
 3439}
 3440
 3441/* If MPLS offload request, verify we are testing hardware MPLS features
 3442 * instead of standard features for the netdev.
 3443 */
 3444#if IS_ENABLED(CONFIG_NET_MPLS_GSO)
 3445static netdev_features_t net_mpls_features(struct sk_buff *skb,
 3446					   netdev_features_t features,
 3447					   __be16 type)
 3448{
 3449	if (eth_p_mpls(type))
 3450		features &= skb->dev->mpls_features;
 3451
 3452	return features;
 3453}
 3454#else
 3455static netdev_features_t net_mpls_features(struct sk_buff *skb,
 3456					   netdev_features_t features,
 3457					   __be16 type)
 3458{
 3459	return features;
 3460}
 3461#endif
 3462
 3463static netdev_features_t harmonize_features(struct sk_buff *skb,
 3464	netdev_features_t features)
 3465{
 3466	__be16 type;
 3467
 3468	type = skb_network_protocol(skb, NULL);
 3469	features = net_mpls_features(skb, features, type);
 3470
 3471	if (skb->ip_summed != CHECKSUM_NONE &&
 3472	    !can_checksum_protocol(features, type)) {
 3473		features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
 3474	}
 3475	if (illegal_highdma(skb->dev, skb))
 3476		features &= ~NETIF_F_SG;
 3477
 3478	return features;
 
 
 3479}
 3480
 3481netdev_features_t passthru_features_check(struct sk_buff *skb,
 3482					  struct net_device *dev,
 3483					  netdev_features_t features)
 
 
 
 
 
 
 3484{
 3485	return features;
 3486}
 3487EXPORT_SYMBOL(passthru_features_check);
 3488
 3489static netdev_features_t dflt_features_check(struct sk_buff *skb,
 3490					     struct net_device *dev,
 3491					     netdev_features_t features)
 3492{
 3493	return vlan_features_check(skb, features);
 3494}
 3495
 3496static netdev_features_t gso_features_check(const struct sk_buff *skb,
 3497					    struct net_device *dev,
 3498					    netdev_features_t features)
 3499{
 3500	u16 gso_segs = skb_shinfo(skb)->gso_segs;
 3501
 3502	if (gso_segs > READ_ONCE(dev->gso_max_segs))
 3503		return features & ~NETIF_F_GSO_MASK;
 3504
 3505	if (!skb_shinfo(skb)->gso_type) {
 3506		skb_warn_bad_offload(skb);
 3507		return features & ~NETIF_F_GSO_MASK;
 3508	}
 3509
 3510	/* Support for GSO partial features requires software
 3511	 * intervention before we can actually process the packets
 3512	 * so we need to strip support for any partial features now
 3513	 * and we can pull them back in after we have partially
 3514	 * segmented the frame.
 3515	 */
 3516	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL))
 3517		features &= ~dev->gso_partial_features;
 3518
 3519	/* Make sure to clear the IPv4 ID mangling feature if the
 3520	 * IPv4 header has the potential to be fragmented.
 3521	 */
 3522	if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) {
 3523		struct iphdr *iph = skb->encapsulation ?
 3524				    inner_ip_hdr(skb) : ip_hdr(skb);
 
 
 3525
 3526		if (!(iph->frag_off & htons(IP_DF)))
 3527			features &= ~NETIF_F_TSO_MANGLEID;
 
 
 
 
 
 3528	}
 3529
 3530	return features;
 3531}
 3532
 3533netdev_features_t netif_skb_features(struct sk_buff *skb)
 3534{
 3535	struct net_device *dev = skb->dev;
 3536	netdev_features_t features = dev->features;
 3537
 3538	if (skb_is_gso(skb))
 3539		features = gso_features_check(skb, dev, features);
 3540
 3541	/* If encapsulation offload request, verify we are testing
 3542	 * hardware encapsulation features instead of standard
 3543	 * features for the netdev
 3544	 */
 3545	if (skb->encapsulation)
 3546		features &= dev->hw_enc_features;
 3547
 3548	if (skb_vlan_tagged(skb))
 3549		features = netdev_intersect_features(features,
 3550						     dev->vlan_features |
 3551						     NETIF_F_HW_VLAN_CTAG_TX |
 3552						     NETIF_F_HW_VLAN_STAG_TX);
 3553
 3554	if (dev->netdev_ops->ndo_features_check)
 3555		features &= dev->netdev_ops->ndo_features_check(skb, dev,
 3556								features);
 3557	else
 3558		features &= dflt_features_check(skb, dev, features);
 3559
 3560	return harmonize_features(skb, features);
 3561}
 3562EXPORT_SYMBOL(netif_skb_features);
 3563
 3564static int xmit_one(struct sk_buff *skb, struct net_device *dev,
 3565		    struct netdev_queue *txq, bool more)
 3566{
 3567	unsigned int len;
 3568	int rc;
 3569
 3570	if (dev_nit_active(dev))
 3571		dev_queue_xmit_nit(skb, dev);
 3572
 3573	len = skb->len;
 3574	trace_net_dev_start_xmit(skb, dev);
 3575	rc = netdev_start_xmit(skb, dev, txq, more);
 3576	trace_net_dev_xmit(skb, rc, dev, len);
 3577
 3578	return rc;
 3579}
 3580
 3581struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
 3582				    struct netdev_queue *txq, int *ret)
 3583{
 3584	struct sk_buff *skb = first;
 3585	int rc = NETDEV_TX_OK;
 3586
 3587	while (skb) {
 3588		struct sk_buff *next = skb->next;
 
 
 
 
 3589
 3590		skb_mark_not_on_list(skb);
 3591		rc = xmit_one(skb, dev, txq, next != NULL);
 3592		if (unlikely(!dev_xmit_complete(rc))) {
 3593			skb->next = next;
 3594			goto out;
 3595		}
 3596
 3597		skb = next;
 3598		if (netif_tx_queue_stopped(txq) && skb) {
 3599			rc = NETDEV_TX_BUSY;
 3600			break;
 3601		}
 
 3602	}
 3603
 3604out:
 3605	*ret = rc;
 3606	return skb;
 3607}
 
 3608
 3609static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
 3610					  netdev_features_t features)
 3611{
 3612	if (skb_vlan_tag_present(skb) &&
 3613	    !vlan_hw_offload_capable(features, skb->vlan_proto))
 3614		skb = __vlan_hwaccel_push_inside(skb);
 3615	return skb;
 
 
 
 
 
 
 
 
 3616}
 3617
 3618int skb_csum_hwoffload_help(struct sk_buff *skb,
 3619			    const netdev_features_t features)
 3620{
 3621	if (unlikely(skb_csum_is_sctp(skb)))
 3622		return !!(features & NETIF_F_SCTP_CRC) ? 0 :
 3623			skb_crc32c_csum_help(skb);
 3624
 3625	if (features & NETIF_F_HW_CSUM)
 3626		return 0;
 3627
 3628	if (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) {
 3629		switch (skb->csum_offset) {
 3630		case offsetof(struct tcphdr, check):
 3631		case offsetof(struct udphdr, check):
 3632			return 0;
 3633		}
 3634	}
 3635
 3636	return skb_checksum_help(skb);
 3637}
 3638EXPORT_SYMBOL(skb_csum_hwoffload_help);
 3639
 3640static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev, bool *again)
 3641{
 3642	netdev_features_t features;
 3643
 3644	features = netif_skb_features(skb);
 3645	skb = validate_xmit_vlan(skb, features);
 3646	if (unlikely(!skb))
 3647		goto out_null;
 3648
 3649	skb = sk_validate_xmit_skb(skb, dev);
 3650	if (unlikely(!skb))
 3651		goto out_null;
 3652
 3653	if (netif_needs_gso(skb, features)) {
 3654		struct sk_buff *segs;
 
 
 
 3655
 3656		segs = skb_gso_segment(skb, features);
 3657		if (IS_ERR(segs)) {
 3658			goto out_kfree_skb;
 3659		} else if (segs) {
 3660			consume_skb(skb);
 3661			skb = segs;
 3662		}
 3663	} else {
 3664		if (skb_needs_linearize(skb, features) &&
 3665		    __skb_linearize(skb))
 3666			goto out_kfree_skb;
 3667
 3668		/* If packet is not checksummed and device does not
 3669		 * support checksumming for this protocol, complete
 3670		 * checksumming here.
 3671		 */
 3672		if (skb->ip_summed == CHECKSUM_PARTIAL) {
 3673			if (skb->encapsulation)
 3674				skb_set_inner_transport_header(skb,
 3675							       skb_checksum_start_offset(skb));
 3676			else
 3677				skb_set_transport_header(skb,
 3678							 skb_checksum_start_offset(skb));
 3679			if (skb_csum_hwoffload_help(skb, features))
 3680				goto out_kfree_skb;
 
 
 
 
 
 
 
 
 
 
 
 
 3681		}
 
 
 
 
 
 
 
 3682	}
 3683
 3684	skb = validate_xmit_xfrm(skb, features, again);
 
 
 3685
 3686	return skb;
 
 3687
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 3688out_kfree_skb:
 3689	kfree_skb(skb);
 3690out_null:
 3691	dev_core_stats_tx_dropped_inc(dev);
 3692	return NULL;
 3693}
 3694
 3695struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev, bool *again)
 
 
 
 
 
 
 
 3696{
 3697	struct sk_buff *next, *head = NULL, *tail;
 
 
 3698
 3699	for (; skb != NULL; skb = next) {
 3700		next = skb->next;
 3701		skb_mark_not_on_list(skb);
 
 
 
 3702
 3703		/* in case skb wont be segmented, point to itself */
 3704		skb->prev = skb;
 
 
 
 3705
 3706		skb = validate_xmit_skb(skb, dev, again);
 3707		if (!skb)
 3708			continue;
 
 
 3709
 3710		if (!head)
 3711			head = skb;
 3712		else
 3713			tail->next = skb;
 3714		/* If skb was segmented, skb->prev points to
 3715		 * the last segment. If not, it still contains skb.
 3716		 */
 3717		tail = skb->prev;
 3718	}
 3719	return head;
 3720}
 3721EXPORT_SYMBOL_GPL(validate_xmit_skb_list);
 3722
 3723static void qdisc_pkt_len_init(struct sk_buff *skb)
 3724{
 3725	const struct skb_shared_info *shinfo = skb_shinfo(skb);
 3726
 3727	qdisc_skb_cb(skb)->pkt_len = skb->len;
 3728
 3729	/* To get more precise estimation of bytes sent on wire,
 3730	 * we add to pkt_len the headers size of all segments
 3731	 */
 3732	if (shinfo->gso_size && skb_transport_header_was_set(skb)) {
 3733		unsigned int hdr_len;
 3734		u16 gso_segs = shinfo->gso_segs;
 3735
 3736		/* mac layer + network layer */
 3737		hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
 3738
 3739		/* + transport layer */
 3740		if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))) {
 3741			const struct tcphdr *th;
 3742			struct tcphdr _tcphdr;
 3743
 3744			th = skb_header_pointer(skb, skb_transport_offset(skb),
 3745						sizeof(_tcphdr), &_tcphdr);
 3746			if (likely(th))
 3747				hdr_len += __tcp_hdrlen(th);
 3748		} else {
 3749			struct udphdr _udphdr;
 3750
 3751			if (skb_header_pointer(skb, skb_transport_offset(skb),
 3752					       sizeof(_udphdr), &_udphdr))
 3753				hdr_len += sizeof(struct udphdr);
 3754		}
 
 
 
 
 3755
 3756		if (shinfo->gso_type & SKB_GSO_DODGY)
 3757			gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
 3758						shinfo->gso_size);
 
 
 
 3759
 3760		qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 3761	}
 
 
 
 
 
 
 3762}
 3763
 3764static int dev_qdisc_enqueue(struct sk_buff *skb, struct Qdisc *q,
 3765			     struct sk_buff **to_free,
 3766			     struct netdev_queue *txq)
 3767{
 3768	int rc;
 
 3769
 3770	rc = q->enqueue(skb, q, to_free) & NET_XMIT_MASK;
 3771	if (rc == NET_XMIT_SUCCESS)
 3772		trace_qdisc_enqueue(q, txq, skb);
 3773	return rc;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 3774}
 3775
 3776static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
 3777				 struct net_device *dev,
 3778				 struct netdev_queue *txq)
 3779{
 3780	spinlock_t *root_lock = qdisc_lock(q);
 3781	struct sk_buff *to_free = NULL;
 3782	bool contended;
 3783	int rc;
 3784
 
 3785	qdisc_calculate_pkt_len(skb, q);
 3786
 3787	if (q->flags & TCQ_F_NOLOCK) {
 3788		if (q->flags & TCQ_F_CAN_BYPASS && nolock_qdisc_is_empty(q) &&
 3789		    qdisc_run_begin(q)) {
 3790			/* Retest nolock_qdisc_is_empty() within the protection
 3791			 * of q->seqlock to protect from racing with requeuing.
 3792			 */
 3793			if (unlikely(!nolock_qdisc_is_empty(q))) {
 3794				rc = dev_qdisc_enqueue(skb, q, &to_free, txq);
 3795				__qdisc_run(q);
 3796				qdisc_run_end(q);
 3797
 3798				goto no_lock_out;
 3799			}
 3800
 3801			qdisc_bstats_cpu_update(q, skb);
 3802			if (sch_direct_xmit(skb, q, dev, txq, NULL, true) &&
 3803			    !nolock_qdisc_is_empty(q))
 3804				__qdisc_run(q);
 3805
 3806			qdisc_run_end(q);
 3807			return NET_XMIT_SUCCESS;
 3808		}
 3809
 3810		rc = dev_qdisc_enqueue(skb, q, &to_free, txq);
 3811		qdisc_run(q);
 3812
 3813no_lock_out:
 3814		if (unlikely(to_free))
 3815			kfree_skb_list_reason(to_free,
 3816					      SKB_DROP_REASON_QDISC_DROP);
 3817		return rc;
 3818	}
 3819
 3820	/*
 3821	 * Heuristic to force contended enqueues to serialize on a
 3822	 * separate lock before trying to get qdisc main lock.
 3823	 * This permits qdisc->running owner to get the lock more
 3824	 * often and dequeue packets faster.
 3825	 * On PREEMPT_RT it is possible to preempt the qdisc owner during xmit
 3826	 * and then other tasks will only enqueue packets. The packets will be
 3827	 * sent after the qdisc owner is scheduled again. To prevent this
 3828	 * scenario the task always serialize on the lock.
 3829	 */
 3830	contended = qdisc_is_running(q) || IS_ENABLED(CONFIG_PREEMPT_RT);
 3831	if (unlikely(contended))
 3832		spin_lock(&q->busylock);
 3833
 3834	spin_lock(root_lock);
 3835	if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
 3836		__qdisc_drop(skb, &to_free);
 3837		rc = NET_XMIT_DROP;
 3838	} else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
 3839		   qdisc_run_begin(q)) {
 3840		/*
 3841		 * This is a work-conserving queue; there are no old skbs
 3842		 * waiting to be sent out; and the qdisc is not running -
 3843		 * xmit the skb directly.
 3844		 */
 
 
 3845
 3846		qdisc_bstats_update(q, skb);
 3847
 3848		if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) {
 3849			if (unlikely(contended)) {
 3850				spin_unlock(&q->busylock);
 3851				contended = false;
 3852			}
 3853			__qdisc_run(q);
 3854		}
 
 3855
 3856		qdisc_run_end(q);
 3857		rc = NET_XMIT_SUCCESS;
 3858	} else {
 3859		rc = dev_qdisc_enqueue(skb, q, &to_free, txq);
 
 3860		if (qdisc_run_begin(q)) {
 3861			if (unlikely(contended)) {
 3862				spin_unlock(&q->busylock);
 3863				contended = false;
 3864			}
 3865			__qdisc_run(q);
 3866			qdisc_run_end(q);
 3867		}
 3868	}
 3869	spin_unlock(root_lock);
 3870	if (unlikely(to_free))
 3871		kfree_skb_list_reason(to_free, SKB_DROP_REASON_QDISC_DROP);
 3872	if (unlikely(contended))
 3873		spin_unlock(&q->busylock);
 3874	return rc;
 3875}
 3876
 3877#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
 3878static void skb_update_prio(struct sk_buff *skb)
 3879{
 3880	const struct netprio_map *map;
 3881	const struct sock *sk;
 3882	unsigned int prioidx;
 3883
 3884	if (skb->priority)
 3885		return;
 3886	map = rcu_dereference_bh(skb->dev->priomap);
 3887	if (!map)
 3888		return;
 3889	sk = skb_to_full_sk(skb);
 3890	if (!sk)
 3891		return;
 3892
 3893	prioidx = sock_cgroup_prioidx(&sk->sk_cgrp_data);
 3894
 3895	if (prioidx < map->priomap_len)
 3896		skb->priority = map->priomap[prioidx];
 3897}
 3898#else
 3899#define skb_update_prio(skb)
 3900#endif
 3901
 3902/**
 3903 *	dev_loopback_xmit - loop back @skb
 3904 *	@net: network namespace this loopback is happening in
 3905 *	@sk:  sk needed to be a netfilter okfn
 3906 *	@skb: buffer to transmit
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 3907 */
 3908int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
 3909{
 3910	skb_reset_mac_header(skb);
 3911	__skb_pull(skb, skb_network_offset(skb));
 3912	skb->pkt_type = PACKET_LOOPBACK;
 3913	if (skb->ip_summed == CHECKSUM_NONE)
 3914		skb->ip_summed = CHECKSUM_UNNECESSARY;
 3915	DEBUG_NET_WARN_ON_ONCE(!skb_dst(skb));
 3916	skb_dst_force(skb);
 3917	netif_rx(skb);
 3918	return 0;
 3919}
 3920EXPORT_SYMBOL(dev_loopback_xmit);
 3921
 3922#ifdef CONFIG_NET_EGRESS
 3923static struct sk_buff *
 3924sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
 3925{
 3926#ifdef CONFIG_NET_CLS_ACT
 3927	struct mini_Qdisc *miniq = rcu_dereference_bh(dev->miniq_egress);
 3928	struct tcf_result cl_res;
 3929
 3930	if (!miniq)
 3931		return skb;
 3932
 3933	/* qdisc_skb_cb(skb)->pkt_len was already set by the caller. */
 3934	tc_skb_cb(skb)->mru = 0;
 3935	tc_skb_cb(skb)->post_ct = false;
 3936	mini_qdisc_bstats_cpu_update(miniq, skb);
 3937
 3938	switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) {
 3939	case TC_ACT_OK:
 3940	case TC_ACT_RECLASSIFY:
 3941		skb->tc_index = TC_H_MIN(cl_res.classid);
 3942		break;
 3943	case TC_ACT_SHOT:
 3944		mini_qdisc_qstats_cpu_drop(miniq);
 3945		*ret = NET_XMIT_DROP;
 3946		kfree_skb_reason(skb, SKB_DROP_REASON_TC_EGRESS);
 3947		return NULL;
 3948	case TC_ACT_STOLEN:
 3949	case TC_ACT_QUEUED:
 3950	case TC_ACT_TRAP:
 3951		*ret = NET_XMIT_SUCCESS;
 3952		consume_skb(skb);
 3953		return NULL;
 3954	case TC_ACT_REDIRECT:
 3955		/* No need to push/pop skb's mac_header here on egress! */
 3956		skb_do_redirect(skb);
 3957		*ret = NET_XMIT_SUCCESS;
 3958		return NULL;
 3959	default:
 3960		break;
 3961	}
 3962#endif /* CONFIG_NET_CLS_ACT */
 3963
 3964	return skb;
 3965}
 3966
 3967static struct netdev_queue *
 3968netdev_tx_queue_mapping(struct net_device *dev, struct sk_buff *skb)
 3969{
 3970	int qm = skb_get_queue_mapping(skb);
 3971
 3972	return netdev_get_tx_queue(dev, netdev_cap_txqueue(dev, qm));
 3973}
 3974
 3975static bool netdev_xmit_txqueue_skipped(void)
 3976{
 3977	return __this_cpu_read(softnet_data.xmit.skip_txqueue);
 3978}
 3979
 3980void netdev_xmit_skip_txqueue(bool skip)
 3981{
 3982	__this_cpu_write(softnet_data.xmit.skip_txqueue, skip);
 3983}
 3984EXPORT_SYMBOL_GPL(netdev_xmit_skip_txqueue);
 3985#endif /* CONFIG_NET_EGRESS */
 3986
 3987#ifdef CONFIG_XPS
 3988static int __get_xps_queue_idx(struct net_device *dev, struct sk_buff *skb,
 3989			       struct xps_dev_maps *dev_maps, unsigned int tci)
 3990{
 3991	int tc = netdev_get_prio_tc_map(dev, skb->priority);
 3992	struct xps_map *map;
 3993	int queue_index = -1;
 3994
 3995	if (tc >= dev_maps->num_tc || tci >= dev_maps->nr_ids)
 3996		return queue_index;
 3997
 3998	tci *= dev_maps->num_tc;
 3999	tci += tc;
 4000
 4001	map = rcu_dereference(dev_maps->attr_map[tci]);
 4002	if (map) {
 4003		if (map->len == 1)
 4004			queue_index = map->queues[0];
 4005		else
 4006			queue_index = map->queues[reciprocal_scale(
 4007						skb_get_hash(skb), map->len)];
 4008		if (unlikely(queue_index >= dev->real_num_tx_queues))
 4009			queue_index = -1;
 4010	}
 4011	return queue_index;
 4012}
 4013#endif
 4014
 4015static int get_xps_queue(struct net_device *dev, struct net_device *sb_dev,
 4016			 struct sk_buff *skb)
 4017{
 4018#ifdef CONFIG_XPS
 4019	struct xps_dev_maps *dev_maps;
 4020	struct sock *sk = skb->sk;
 4021	int queue_index = -1;
 4022
 4023	if (!static_key_false(&xps_needed))
 4024		return -1;
 4025
 4026	rcu_read_lock();
 4027	if (!static_key_false(&xps_rxqs_needed))
 4028		goto get_cpus_map;
 4029
 4030	dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_RXQS]);
 4031	if (dev_maps) {
 4032		int tci = sk_rx_queue_get(sk);
 4033
 4034		if (tci >= 0)
 4035			queue_index = __get_xps_queue_idx(dev, skb, dev_maps,
 4036							  tci);
 4037	}
 4038
 4039get_cpus_map:
 4040	if (queue_index < 0) {
 4041		dev_maps = rcu_dereference(sb_dev->xps_maps[XPS_CPUS]);
 4042		if (dev_maps) {
 4043			unsigned int tci = skb->sender_cpu - 1;
 4044
 4045			queue_index = __get_xps_queue_idx(dev, skb, dev_maps,
 4046							  tci);
 4047		}
 4048	}
 4049	rcu_read_unlock();
 4050
 4051	return queue_index;
 4052#else
 4053	return -1;
 4054#endif
 4055}
 4056
 4057u16 dev_pick_tx_zero(struct net_device *dev, struct sk_buff *skb,
 4058		     struct net_device *sb_dev)
 4059{
 4060	return 0;
 4061}
 4062EXPORT_SYMBOL(dev_pick_tx_zero);
 4063
 4064u16 dev_pick_tx_cpu_id(struct net_device *dev, struct sk_buff *skb,
 4065		       struct net_device *sb_dev)
 4066{
 4067	return (u16)raw_smp_processor_id() % dev->real_num_tx_queues;
 4068}
 4069EXPORT_SYMBOL(dev_pick_tx_cpu_id);
 4070
 4071u16 netdev_pick_tx(struct net_device *dev, struct sk_buff *skb,
 4072		     struct net_device *sb_dev)
 4073{
 4074	struct sock *sk = skb->sk;
 4075	int queue_index = sk_tx_queue_get(sk);
 4076
 4077	sb_dev = sb_dev ? : dev;
 4078
 4079	if (queue_index < 0 || skb->ooo_okay ||
 4080	    queue_index >= dev->real_num_tx_queues) {
 4081		int new_index = get_xps_queue(dev, sb_dev, skb);
 4082
 4083		if (new_index < 0)
 4084			new_index = skb_tx_hash(dev, sb_dev, skb);
 4085
 4086		if (queue_index != new_index && sk &&
 4087		    sk_fullsock(sk) &&
 4088		    rcu_access_pointer(sk->sk_dst_cache))
 4089			sk_tx_queue_set(sk, new_index);
 4090
 4091		queue_index = new_index;
 4092	}
 4093
 4094	return queue_index;
 4095}
 4096EXPORT_SYMBOL(netdev_pick_tx);
 4097
 4098struct netdev_queue *netdev_core_pick_tx(struct net_device *dev,
 4099					 struct sk_buff *skb,
 4100					 struct net_device *sb_dev)
 4101{
 4102	int queue_index = 0;
 4103
 4104#ifdef CONFIG_XPS
 4105	u32 sender_cpu = skb->sender_cpu - 1;
 4106
 4107	if (sender_cpu >= (u32)NR_CPUS)
 4108		skb->sender_cpu = raw_smp_processor_id() + 1;
 4109#endif
 4110
 4111	if (dev->real_num_tx_queues != 1) {
 4112		const struct net_device_ops *ops = dev->netdev_ops;
 4113
 4114		if (ops->ndo_select_queue)
 4115			queue_index = ops->ndo_select_queue(dev, skb, sb_dev);
 4116		else
 4117			queue_index = netdev_pick_tx(dev, skb, sb_dev);
 4118
 4119		queue_index = netdev_cap_txqueue(dev, queue_index);
 4120	}
 4121
 4122	skb_set_queue_mapping(skb, queue_index);
 4123	return netdev_get_tx_queue(dev, queue_index);
 4124}
 4125
 4126/**
 4127 * __dev_queue_xmit() - transmit a buffer
 4128 * @skb:	buffer to transmit
 4129 * @sb_dev:	suboordinate device used for L2 forwarding offload
 4130 *
 4131 * Queue a buffer for transmission to a network device. The caller must
 4132 * have set the device and priority and built the buffer before calling
 4133 * this function. The function can be called from an interrupt.
 4134 *
 4135 * When calling this method, interrupts MUST be enabled. This is because
 4136 * the BH enable code must have IRQs enabled so that it will not deadlock.
 4137 *
 4138 * Regardless of the return value, the skb is consumed, so it is currently
 4139 * difficult to retry a send to this method. (You can bump the ref count
 4140 * before sending to hold a reference for retry if you are careful.)
 4141 *
 4142 * Return:
 4143 * * 0				- buffer successfully transmitted
 4144 * * positive qdisc return code	- NET_XMIT_DROP etc.
 4145 * * negative errno		- other errors
 4146 */
 4147int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev)
 4148{
 4149	struct net_device *dev = skb->dev;
 4150	struct netdev_queue *txq = NULL;
 4151	struct Qdisc *q;
 4152	int rc = -ENOMEM;
 4153	bool again = false;
 4154
 4155	skb_reset_mac_header(skb);
 4156	skb_assert_len(skb);
 4157
 4158	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
 4159		__skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED);
 4160
 4161	/* Disable soft irqs for various locks below. Also
 4162	 * stops preemption for RCU.
 4163	 */
 4164	rcu_read_lock_bh();
 4165
 4166	skb_update_prio(skb);
 
 4167
 4168	qdisc_pkt_len_init(skb);
 4169#ifdef CONFIG_NET_CLS_ACT
 4170	skb->tc_at_ingress = 0;
 4171#endif
 4172#ifdef CONFIG_NET_EGRESS
 4173	if (static_branch_unlikely(&egress_needed_key)) {
 4174		if (nf_hook_egress_active()) {
 4175			skb = nf_hook_egress(skb, &rc, dev);
 4176			if (!skb)
 4177				goto out;
 4178		}
 4179
 4180		netdev_xmit_skip_txqueue(false);
 4181
 4182		nf_skip_egress(skb, true);
 4183		skb = sch_handle_egress(skb, &rc, dev);
 4184		if (!skb)
 4185			goto out;
 4186		nf_skip_egress(skb, false);
 4187
 4188		if (netdev_xmit_txqueue_skipped())
 4189			txq = netdev_tx_queue_mapping(dev, skb);
 4190	}
 4191#endif
 4192	/* If device/qdisc don't need skb->dst, release it right now while
 4193	 * its hot in this cpu cache.
 4194	 */
 4195	if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
 4196		skb_dst_drop(skb);
 4197	else
 4198		skb_dst_force(skb);
 4199
 4200	if (!txq)
 4201		txq = netdev_core_pick_tx(dev, skb, sb_dev);
 4202
 4203	q = rcu_dereference_bh(txq->qdisc);
 4204
 4205	trace_net_dev_queue(skb);
 4206	if (q->enqueue) {
 4207		rc = __dev_xmit_skb(skb, q, dev, txq);
 4208		goto out;
 4209	}
 4210
 4211	/* The device has no queue. Common case for software devices:
 4212	 * loopback, all the sorts of tunnels...
 4213
 4214	 * Really, it is unlikely that netif_tx_lock protection is necessary
 4215	 * here.  (f.e. loopback and IP tunnels are clean ignoring statistics
 4216	 * counters.)
 4217	 * However, it is possible, that they rely on protection
 4218	 * made by us here.
 4219
 4220	 * Check this and shot the lock. It is not prone from deadlocks.
 4221	 *Either shot noqueue qdisc, it is even simpler 8)
 4222	 */
 4223	if (dev->flags & IFF_UP) {
 4224		int cpu = smp_processor_id(); /* ok because BHs are off */
 4225
 4226		/* Other cpus might concurrently change txq->xmit_lock_owner
 4227		 * to -1 or to their cpu id, but not to our id.
 4228		 */
 4229		if (READ_ONCE(txq->xmit_lock_owner) != cpu) {
 4230			if (dev_xmit_recursion())
 4231				goto recursion_alert;
 4232
 4233			skb = validate_xmit_skb(skb, dev, &again);
 4234			if (!skb)
 4235				goto out;
 4236
 4237			HARD_TX_LOCK(dev, txq, cpu);
 4238
 4239			if (!netif_xmit_stopped(txq)) {
 4240				dev_xmit_recursion_inc();
 4241				skb = dev_hard_start_xmit(skb, dev, txq, &rc);
 4242				dev_xmit_recursion_dec();
 4243				if (dev_xmit_complete(rc)) {
 4244					HARD_TX_UNLOCK(dev, txq);
 4245					goto out;
 4246				}
 4247			}
 4248			HARD_TX_UNLOCK(dev, txq);
 4249			net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
 4250					     dev->name);
 
 4251		} else {
 4252			/* Recursion is detected! It is possible,
 4253			 * unfortunately
 4254			 */
 4255recursion_alert:
 4256			net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
 4257					     dev->name);
 
 4258		}
 4259	}
 4260
 4261	rc = -ENETDOWN;
 4262	rcu_read_unlock_bh();
 4263
 4264	dev_core_stats_tx_dropped_inc(dev);
 4265	kfree_skb_list(skb);
 4266	return rc;
 4267out:
 4268	rcu_read_unlock_bh();
 4269	return rc;
 4270}
 4271EXPORT_SYMBOL(__dev_queue_xmit);
 4272
 4273int __dev_direct_xmit(struct sk_buff *skb, u16 queue_id)
 4274{
 4275	struct net_device *dev = skb->dev;
 4276	struct sk_buff *orig_skb = skb;
 4277	struct netdev_queue *txq;
 4278	int ret = NETDEV_TX_BUSY;
 4279	bool again = false;
 4280
 4281	if (unlikely(!netif_running(dev) ||
 4282		     !netif_carrier_ok(dev)))
 4283		goto drop;
 4284
 4285	skb = validate_xmit_skb_list(skb, dev, &again);
 4286	if (skb != orig_skb)
 4287		goto drop;
 4288
 4289	skb_set_queue_mapping(skb, queue_id);
 4290	txq = skb_get_tx_queue(dev, skb);
 4291
 4292	local_bh_disable();
 4293
 4294	dev_xmit_recursion_inc();
 4295	HARD_TX_LOCK(dev, txq, smp_processor_id());
 4296	if (!netif_xmit_frozen_or_drv_stopped(txq))
 4297		ret = netdev_start_xmit(skb, dev, txq, false);
 4298	HARD_TX_UNLOCK(dev, txq);
 4299	dev_xmit_recursion_dec();
 4300
 4301	local_bh_enable();
 4302	return ret;
 4303drop:
 4304	dev_core_stats_tx_dropped_inc(dev);
 4305	kfree_skb_list(skb);
 4306	return NET_XMIT_DROP;
 4307}
 4308EXPORT_SYMBOL(__dev_direct_xmit);
 4309
 4310/*************************************************************************
 4311 *			Receiver routines
 4312 *************************************************************************/
 4313
 4314int netdev_max_backlog __read_mostly = 1000;
 4315EXPORT_SYMBOL(netdev_max_backlog);
 4316
 4317int netdev_tstamp_prequeue __read_mostly = 1;
 4318unsigned int sysctl_skb_defer_max __read_mostly = 64;
 4319int netdev_budget __read_mostly = 300;
 4320/* Must be at least 2 jiffes to guarantee 1 jiffy timeout */
 4321unsigned int __read_mostly netdev_budget_usecs = 2 * USEC_PER_SEC / HZ;
 4322int weight_p __read_mostly = 64;           /* old backlog weight */
 4323int dev_weight_rx_bias __read_mostly = 1;  /* bias for backlog weight */
 4324int dev_weight_tx_bias __read_mostly = 1;  /* bias for output_queue quota */
 4325int dev_rx_weight __read_mostly = 64;
 4326int dev_tx_weight __read_mostly = 64;
 4327
 4328/* Called with irq disabled */
 4329static inline void ____napi_schedule(struct softnet_data *sd,
 4330				     struct napi_struct *napi)
 4331{
 4332	struct task_struct *thread;
 
 
 4333
 4334	lockdep_assert_irqs_disabled();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 4335
 4336	if (test_bit(NAPI_STATE_THREADED, &napi->state)) {
 4337		/* Paired with smp_mb__before_atomic() in
 4338		 * napi_enable()/dev_set_threaded().
 4339		 * Use READ_ONCE() to guarantee a complete
 4340		 * read on napi->thread. Only call
 4341		 * wake_up_process() when it's not NULL.
 4342		 */
 4343		thread = READ_ONCE(napi->thread);
 4344		if (thread) {
 4345			/* Avoid doing set_bit() if the thread is in
 4346			 * INTERRUPTIBLE state, cause napi_thread_wait()
 4347			 * makes sure to proceed with napi polling
 4348			 * if the thread is explicitly woken from here.
 4349			 */
 4350			if (READ_ONCE(thread->__state) != TASK_INTERRUPTIBLE)
 4351				set_bit(NAPI_STATE_SCHED_THREADED, &napi->state);
 4352			wake_up_process(thread);
 4353			return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 4354		}
 4355	}
 4356
 4357	list_add_tail(&napi->poll_list, &sd->poll_list);
 4358	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
 
 
 
 
 
 
 
 
 4359}
 
 4360
 4361#ifdef CONFIG_RPS
 4362
 4363/* One global table that all flow-based protocols share. */
 4364struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
 4365EXPORT_SYMBOL(rps_sock_flow_table);
 4366u32 rps_cpu_mask __read_mostly;
 4367EXPORT_SYMBOL(rps_cpu_mask);
 4368
 4369struct static_key_false rps_needed __read_mostly;
 4370EXPORT_SYMBOL(rps_needed);
 4371struct static_key_false rfs_needed __read_mostly;
 4372EXPORT_SYMBOL(rfs_needed);
 4373
 4374static struct rps_dev_flow *
 4375set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
 4376	    struct rps_dev_flow *rflow, u16 next_cpu)
 4377{
 4378	if (next_cpu < nr_cpu_ids) {
 
 
 
 4379#ifdef CONFIG_RFS_ACCEL
 4380		struct netdev_rx_queue *rxqueue;
 4381		struct rps_dev_flow_table *flow_table;
 4382		struct rps_dev_flow *old_rflow;
 4383		u32 flow_id;
 4384		u16 rxq_index;
 4385		int rc;
 4386
 4387		/* Should we steer this flow to a different hardware queue? */
 4388		if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
 4389		    !(dev->features & NETIF_F_NTUPLE))
 4390			goto out;
 4391		rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
 4392		if (rxq_index == skb_get_rx_queue(skb))
 4393			goto out;
 4394
 4395		rxqueue = dev->_rx + rxq_index;
 4396		flow_table = rcu_dereference(rxqueue->rps_flow_table);
 4397		if (!flow_table)
 4398			goto out;
 4399		flow_id = skb_get_hash(skb) & flow_table->mask;
 4400		rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
 4401							rxq_index, flow_id);
 4402		if (rc < 0)
 4403			goto out;
 4404		old_rflow = rflow;
 4405		rflow = &flow_table->flows[flow_id];
 
 4406		rflow->filter = rc;
 4407		if (old_rflow->filter == rflow->filter)
 4408			old_rflow->filter = RPS_NO_FILTER;
 4409	out:
 4410#endif
 4411		rflow->last_qtail =
 4412			per_cpu(softnet_data, next_cpu).input_queue_head;
 4413	}
 4414
 4415	rflow->cpu = next_cpu;
 4416	return rflow;
 4417}
 4418
 4419/*
 4420 * get_rps_cpu is called from netif_receive_skb and returns the target
 4421 * CPU from the RPS map of the receiving queue for a given skb.
 4422 * rcu_read_lock must be held on entry.
 4423 */
 4424static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
 4425		       struct rps_dev_flow **rflowp)
 4426{
 4427	const struct rps_sock_flow_table *sock_flow_table;
 4428	struct netdev_rx_queue *rxqueue = dev->_rx;
 4429	struct rps_dev_flow_table *flow_table;
 4430	struct rps_map *map;
 
 
 4431	int cpu = -1;
 4432	u32 tcpu;
 4433	u32 hash;
 4434
 4435	if (skb_rx_queue_recorded(skb)) {
 4436		u16 index = skb_get_rx_queue(skb);
 4437
 4438		if (unlikely(index >= dev->real_num_rx_queues)) {
 4439			WARN_ONCE(dev->real_num_rx_queues > 1,
 4440				  "%s received packet on queue %u, but number "
 4441				  "of RX queues is %u\n",
 4442				  dev->name, index, dev->real_num_rx_queues);
 4443			goto done;
 4444		}
 4445		rxqueue += index;
 4446	}
 4447
 4448	/* Avoid computing hash if RFS/RPS is not active for this rxqueue */
 4449
 4450	flow_table = rcu_dereference(rxqueue->rps_flow_table);
 4451	map = rcu_dereference(rxqueue->rps_map);
 4452	if (!flow_table && !map)
 
 
 
 
 
 
 
 
 4453		goto done;
 
 4454
 4455	skb_reset_network_header(skb);
 4456	hash = skb_get_hash(skb);
 4457	if (!hash)
 4458		goto done;
 4459
 
 4460	sock_flow_table = rcu_dereference(rps_sock_flow_table);
 4461	if (flow_table && sock_flow_table) {
 
 4462		struct rps_dev_flow *rflow;
 4463		u32 next_cpu;
 4464		u32 ident;
 4465
 4466		/* First check into global flow table if there is a match */
 4467		ident = sock_flow_table->ents[hash & sock_flow_table->mask];
 4468		if ((ident ^ hash) & ~rps_cpu_mask)
 4469			goto try_rps;
 4470
 4471		next_cpu = ident & rps_cpu_mask;
 4472
 4473		/* OK, now we know there is a match,
 4474		 * we can look at the local (per receive queue) flow table
 4475		 */
 4476		rflow = &flow_table->flows[hash & flow_table->mask];
 4477		tcpu = rflow->cpu;
 4478
 
 
 
 4479		/*
 4480		 * If the desired CPU (where last recvmsg was done) is
 4481		 * different from current CPU (one in the rx-queue flow
 4482		 * table entry), switch if one of the following holds:
 4483		 *   - Current CPU is unset (>= nr_cpu_ids).
 4484		 *   - Current CPU is offline.
 4485		 *   - The current CPU's queue tail has advanced beyond the
 4486		 *     last packet that was enqueued using this table entry.
 4487		 *     This guarantees that all previous packets for the flow
 4488		 *     have been dequeued, thus preserving in order delivery.
 4489		 */
 4490		if (unlikely(tcpu != next_cpu) &&
 4491		    (tcpu >= nr_cpu_ids || !cpu_online(tcpu) ||
 4492		     ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
 4493		      rflow->last_qtail)) >= 0)) {
 4494			tcpu = next_cpu;
 4495			rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
 4496		}
 4497
 4498		if (tcpu < nr_cpu_ids && cpu_online(tcpu)) {
 4499			*rflowp = rflow;
 4500			cpu = tcpu;
 4501			goto done;
 4502		}
 4503	}
 4504
 4505try_rps:
 4506
 4507	if (map) {
 4508		tcpu = map->cpus[reciprocal_scale(hash, map->len)];
 
 4509		if (cpu_online(tcpu)) {
 4510			cpu = tcpu;
 4511			goto done;
 4512		}
 4513	}
 4514
 4515done:
 4516	return cpu;
 4517}
 4518
 4519#ifdef CONFIG_RFS_ACCEL
 4520
 4521/**
 4522 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
 4523 * @dev: Device on which the filter was set
 4524 * @rxq_index: RX queue index
 4525 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
 4526 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
 4527 *
 4528 * Drivers that implement ndo_rx_flow_steer() should periodically call
 4529 * this function for each installed filter and remove the filters for
 4530 * which it returns %true.
 4531 */
 4532bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
 4533			 u32 flow_id, u16 filter_id)
 4534{
 4535	struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
 4536	struct rps_dev_flow_table *flow_table;
 4537	struct rps_dev_flow *rflow;
 4538	bool expire = true;
 4539	unsigned int cpu;
 4540
 4541	rcu_read_lock();
 4542	flow_table = rcu_dereference(rxqueue->rps_flow_table);
 4543	if (flow_table && flow_id <= flow_table->mask) {
 4544		rflow = &flow_table->flows[flow_id];
 4545		cpu = READ_ONCE(rflow->cpu);
 4546		if (rflow->filter == filter_id && cpu < nr_cpu_ids &&
 4547		    ((int)(per_cpu(softnet_data, cpu).input_queue_head -
 4548			   rflow->last_qtail) <
 4549		     (int)(10 * flow_table->mask)))
 4550			expire = false;
 4551	}
 4552	rcu_read_unlock();
 4553	return expire;
 4554}
 4555EXPORT_SYMBOL(rps_may_expire_flow);
 4556
 4557#endif /* CONFIG_RFS_ACCEL */
 4558
 4559/* Called from hardirq (IPI) context */
 4560static void rps_trigger_softirq(void *data)
 4561{
 4562	struct softnet_data *sd = data;
 4563
 4564	____napi_schedule(sd, &sd->backlog);
 4565	sd->received_rps++;
 4566}
 4567
 4568#endif /* CONFIG_RPS */
 4569
 4570/* Called from hardirq (IPI) context */
 4571static void trigger_rx_softirq(void *data)
 4572{
 4573	struct softnet_data *sd = data;
 4574
 4575	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
 4576	smp_store_release(&sd->defer_ipi_scheduled, 0);
 4577}
 4578
 4579/*
 4580 * Check if this softnet_data structure is another cpu one
 4581 * If yes, queue it to our IPI list and return 1
 4582 * If no, return 0
 4583 */
 4584static int napi_schedule_rps(struct softnet_data *sd)
 4585{
 4586	struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
 4587
 4588#ifdef CONFIG_RPS
 
 
 4589	if (sd != mysd) {
 4590		sd->rps_ipi_next = mysd->rps_ipi_list;
 4591		mysd->rps_ipi_list = sd;
 4592
 4593		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
 4594		return 1;
 4595	}
 4596#endif /* CONFIG_RPS */
 4597	__napi_schedule_irqoff(&mysd->backlog);
 4598	return 0;
 4599}
 4600
 4601#ifdef CONFIG_NET_FLOW_LIMIT
 4602int netdev_flow_limit_table_len __read_mostly = (1 << 12);
 4603#endif
 4604
 4605static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
 4606{
 4607#ifdef CONFIG_NET_FLOW_LIMIT
 4608	struct sd_flow_limit *fl;
 4609	struct softnet_data *sd;
 4610	unsigned int old_flow, new_flow;
 4611
 4612	if (qlen < (READ_ONCE(netdev_max_backlog) >> 1))
 4613		return false;
 4614
 4615	sd = this_cpu_ptr(&softnet_data);
 4616
 4617	rcu_read_lock();
 4618	fl = rcu_dereference(sd->flow_limit);
 4619	if (fl) {
 4620		new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
 4621		old_flow = fl->history[fl->history_head];
 4622		fl->history[fl->history_head] = new_flow;
 4623
 4624		fl->history_head++;
 4625		fl->history_head &= FLOW_LIMIT_HISTORY - 1;
 4626
 4627		if (likely(fl->buckets[old_flow]))
 4628			fl->buckets[old_flow]--;
 4629
 4630		if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
 4631			fl->count++;
 4632			rcu_read_unlock();
 4633			return true;
 4634		}
 4635	}
 4636	rcu_read_unlock();
 4637#endif
 4638	return false;
 4639}
 4640
 4641/*
 4642 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
 4643 * queue (may be a remote CPU queue).
 4644 */
 4645static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
 4646			      unsigned int *qtail)
 4647{
 4648	enum skb_drop_reason reason;
 4649	struct softnet_data *sd;
 4650	unsigned long flags;
 4651	unsigned int qlen;
 4652
 4653	reason = SKB_DROP_REASON_NOT_SPECIFIED;
 4654	sd = &per_cpu(softnet_data, cpu);
 4655
 4656	rps_lock_irqsave(sd, &flags);
 4657	if (!netif_running(skb->dev))
 4658		goto drop;
 4659	qlen = skb_queue_len(&sd->input_pkt_queue);
 4660	if (qlen <= READ_ONCE(netdev_max_backlog) && !skb_flow_limit(skb, qlen)) {
 4661		if (qlen) {
 4662enqueue:
 4663			__skb_queue_tail(&sd->input_pkt_queue, skb);
 4664			input_queue_tail_incr_save(sd, qtail);
 4665			rps_unlock_irq_restore(sd, &flags);
 
 4666			return NET_RX_SUCCESS;
 4667		}
 4668
 4669		/* Schedule NAPI for backlog device
 4670		 * We can use non atomic operation since we own the queue lock
 4671		 */
 4672		if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state))
 4673			napi_schedule_rps(sd);
 
 
 4674		goto enqueue;
 4675	}
 4676	reason = SKB_DROP_REASON_CPU_BACKLOG;
 4677
 4678drop:
 4679	sd->dropped++;
 4680	rps_unlock_irq_restore(sd, &flags);
 4681
 4682	dev_core_stats_rx_dropped_inc(skb->dev);
 4683	kfree_skb_reason(skb, reason);
 4684	return NET_RX_DROP;
 4685}
 4686
 4687static struct netdev_rx_queue *netif_get_rxqueue(struct sk_buff *skb)
 4688{
 4689	struct net_device *dev = skb->dev;
 4690	struct netdev_rx_queue *rxqueue;
 4691
 4692	rxqueue = dev->_rx;
 4693
 4694	if (skb_rx_queue_recorded(skb)) {
 4695		u16 index = skb_get_rx_queue(skb);
 4696
 4697		if (unlikely(index >= dev->real_num_rx_queues)) {
 4698			WARN_ONCE(dev->real_num_rx_queues > 1,
 4699				  "%s received packet on queue %u, but number "
 4700				  "of RX queues is %u\n",
 4701				  dev->name, index, dev->real_num_rx_queues);
 4702
 4703			return rxqueue; /* Return first rxqueue */
 4704		}
 4705		rxqueue += index;
 4706	}
 4707	return rxqueue;
 4708}
 4709
 4710u32 bpf_prog_run_generic_xdp(struct sk_buff *skb, struct xdp_buff *xdp,
 4711			     struct bpf_prog *xdp_prog)
 4712{
 4713	void *orig_data, *orig_data_end, *hard_start;
 4714	struct netdev_rx_queue *rxqueue;
 4715	bool orig_bcast, orig_host;
 4716	u32 mac_len, frame_sz;
 4717	__be16 orig_eth_type;
 4718	struct ethhdr *eth;
 4719	u32 metalen, act;
 4720	int off;
 4721
 4722	/* The XDP program wants to see the packet starting at the MAC
 4723	 * header.
 4724	 */
 4725	mac_len = skb->data - skb_mac_header(skb);
 4726	hard_start = skb->data - skb_headroom(skb);
 4727
 4728	/* SKB "head" area always have tailroom for skb_shared_info */
 4729	frame_sz = (void *)skb_end_pointer(skb) - hard_start;
 4730	frame_sz += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
 4731
 4732	rxqueue = netif_get_rxqueue(skb);
 4733	xdp_init_buff(xdp, frame_sz, &rxqueue->xdp_rxq);
 4734	xdp_prepare_buff(xdp, hard_start, skb_headroom(skb) - mac_len,
 4735			 skb_headlen(skb) + mac_len, true);
 4736
 4737	orig_data_end = xdp->data_end;
 4738	orig_data = xdp->data;
 4739	eth = (struct ethhdr *)xdp->data;
 4740	orig_host = ether_addr_equal_64bits(eth->h_dest, skb->dev->dev_addr);
 4741	orig_bcast = is_multicast_ether_addr_64bits(eth->h_dest);
 4742	orig_eth_type = eth->h_proto;
 4743
 4744	act = bpf_prog_run_xdp(xdp_prog, xdp);
 4745
 4746	/* check if bpf_xdp_adjust_head was used */
 4747	off = xdp->data - orig_data;
 4748	if (off) {
 4749		if (off > 0)
 4750			__skb_pull(skb, off);
 4751		else if (off < 0)
 4752			__skb_push(skb, -off);
 4753
 4754		skb->mac_header += off;
 4755		skb_reset_network_header(skb);
 4756	}
 4757
 4758	/* check if bpf_xdp_adjust_tail was used */
 4759	off = xdp->data_end - orig_data_end;
 4760	if (off != 0) {
 4761		skb_set_tail_pointer(skb, xdp->data_end - xdp->data);
 4762		skb->len += off; /* positive on grow, negative on shrink */
 4763	}
 4764
 4765	/* check if XDP changed eth hdr such SKB needs update */
 4766	eth = (struct ethhdr *)xdp->data;
 4767	if ((orig_eth_type != eth->h_proto) ||
 4768	    (orig_host != ether_addr_equal_64bits(eth->h_dest,
 4769						  skb->dev->dev_addr)) ||
 4770	    (orig_bcast != is_multicast_ether_addr_64bits(eth->h_dest))) {
 4771		__skb_push(skb, ETH_HLEN);
 4772		skb->pkt_type = PACKET_HOST;
 4773		skb->protocol = eth_type_trans(skb, skb->dev);
 4774	}
 4775
 4776	/* Redirect/Tx gives L2 packet, code that will reuse skb must __skb_pull
 4777	 * before calling us again on redirect path. We do not call do_redirect
 4778	 * as we leave that up to the caller.
 4779	 *
 4780	 * Caller is responsible for managing lifetime of skb (i.e. calling
 4781	 * kfree_skb in response to actions it cannot handle/XDP_DROP).
 4782	 */
 4783	switch (act) {
 4784	case XDP_REDIRECT:
 4785	case XDP_TX:
 4786		__skb_push(skb, mac_len);
 4787		break;
 4788	case XDP_PASS:
 4789		metalen = xdp->data - xdp->data_meta;
 4790		if (metalen)
 4791			skb_metadata_set(skb, metalen);
 4792		break;
 4793	}
 4794
 4795	return act;
 4796}
 4797
 4798static u32 netif_receive_generic_xdp(struct sk_buff *skb,
 4799				     struct xdp_buff *xdp,
 4800				     struct bpf_prog *xdp_prog)
 4801{
 4802	u32 act = XDP_DROP;
 4803
 4804	/* Reinjected packets coming from act_mirred or similar should
 4805	 * not get XDP generic processing.
 4806	 */
 4807	if (skb_is_redirected(skb))
 4808		return XDP_PASS;
 4809
 4810	/* XDP packets must be linear and must have sufficient headroom
 4811	 * of XDP_PACKET_HEADROOM bytes. This is the guarantee that also
 4812	 * native XDP provides, thus we need to do it here as well.
 4813	 */
 4814	if (skb_cloned(skb) || skb_is_nonlinear(skb) ||
 4815	    skb_headroom(skb) < XDP_PACKET_HEADROOM) {
 4816		int hroom = XDP_PACKET_HEADROOM - skb_headroom(skb);
 4817		int troom = skb->tail + skb->data_len - skb->end;
 4818
 4819		/* In case we have to go down the path and also linearize,
 4820		 * then lets do the pskb_expand_head() work just once here.
 4821		 */
 4822		if (pskb_expand_head(skb,
 4823				     hroom > 0 ? ALIGN(hroom, NET_SKB_PAD) : 0,
 4824				     troom > 0 ? troom + 128 : 0, GFP_ATOMIC))
 4825			goto do_drop;
 4826		if (skb_linearize(skb))
 4827			goto do_drop;
 4828	}
 4829
 4830	act = bpf_prog_run_generic_xdp(skb, xdp, xdp_prog);
 4831	switch (act) {
 4832	case XDP_REDIRECT:
 4833	case XDP_TX:
 4834	case XDP_PASS:
 4835		break;
 4836	default:
 4837		bpf_warn_invalid_xdp_action(skb->dev, xdp_prog, act);
 4838		fallthrough;
 4839	case XDP_ABORTED:
 4840		trace_xdp_exception(skb->dev, xdp_prog, act);
 4841		fallthrough;
 4842	case XDP_DROP:
 4843	do_drop:
 4844		kfree_skb(skb);
 4845		break;
 4846	}
 4847
 4848	return act;
 
 
 4849}
 4850
 4851/* When doing generic XDP we have to bypass the qdisc layer and the
 4852 * network taps in order to match in-driver-XDP behavior. This also means
 4853 * that XDP packets are able to starve other packets going through a qdisc,
 4854 * and DDOS attacks will be more effective. In-driver-XDP use dedicated TX
 4855 * queues, so they do not have this starvation issue.
 
 
 
 
 
 
 
 
 4856 */
 4857void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog)
 4858{
 4859	struct net_device *dev = skb->dev;
 4860	struct netdev_queue *txq;
 4861	bool free_skb = true;
 4862	int cpu, rc;
 4863
 4864	txq = netdev_core_pick_tx(dev, skb, NULL);
 4865	cpu = smp_processor_id();
 4866	HARD_TX_LOCK(dev, txq, cpu);
 4867	if (!netif_xmit_frozen_or_drv_stopped(txq)) {
 4868		rc = netdev_start_xmit(skb, dev, txq, 0);
 4869		if (dev_xmit_complete(rc))
 4870			free_skb = false;
 4871	}
 4872	HARD_TX_UNLOCK(dev, txq);
 4873	if (free_skb) {
 4874		trace_xdp_exception(dev, xdp_prog, XDP_TX);
 4875		dev_core_stats_tx_dropped_inc(dev);
 4876		kfree_skb(skb);
 4877	}
 4878}
 4879
 4880static DEFINE_STATIC_KEY_FALSE(generic_xdp_needed_key);
 4881
 4882int do_xdp_generic(struct bpf_prog *xdp_prog, struct sk_buff *skb)
 4883{
 4884	if (xdp_prog) {
 4885		struct xdp_buff xdp;
 4886		u32 act;
 4887		int err;
 4888
 4889		act = netif_receive_generic_xdp(skb, &xdp, xdp_prog);
 4890		if (act != XDP_PASS) {
 4891			switch (act) {
 4892			case XDP_REDIRECT:
 4893				err = xdp_do_generic_redirect(skb->dev, skb,
 4894							      &xdp, xdp_prog);
 4895				if (err)
 4896					goto out_redir;
 4897				break;
 4898			case XDP_TX:
 4899				generic_xdp_tx(skb, xdp_prog);
 4900				break;
 4901			}
 4902			return XDP_DROP;
 4903		}
 4904	}
 4905	return XDP_PASS;
 4906out_redir:
 4907	kfree_skb_reason(skb, SKB_DROP_REASON_XDP);
 4908	return XDP_DROP;
 4909}
 4910EXPORT_SYMBOL_GPL(do_xdp_generic);
 4911
 4912static int netif_rx_internal(struct sk_buff *skb)
 4913{
 4914	int ret;
 4915
 4916	net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
 
 
 4917
 4918	trace_netif_rx(skb);
 
 4919
 
 4920#ifdef CONFIG_RPS
 4921	if (static_branch_unlikely(&rps_needed)) {
 4922		struct rps_dev_flow voidflow, *rflow = &voidflow;
 4923		int cpu;
 4924
 
 4925		rcu_read_lock();
 4926
 4927		cpu = get_rps_cpu(skb->dev, skb, &rflow);
 4928		if (cpu < 0)
 4929			cpu = smp_processor_id();
 4930
 4931		ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
 4932
 4933		rcu_read_unlock();
 4934	} else
 4935#endif
 
 4936	{
 4937		unsigned int qtail;
 4938
 4939		ret = enqueue_to_backlog(skb, smp_processor_id(), &qtail);
 4940	}
 
 4941	return ret;
 4942}
 
 4943
 4944/**
 4945 *	__netif_rx	-	Slightly optimized version of netif_rx
 4946 *	@skb: buffer to post
 4947 *
 4948 *	This behaves as netif_rx except that it does not disable bottom halves.
 4949 *	As a result this function may only be invoked from the interrupt context
 4950 *	(either hard or soft interrupt).
 4951 */
 4952int __netif_rx(struct sk_buff *skb)
 4953{
 4954	int ret;
 4955
 4956	lockdep_assert_once(hardirq_count() | softirq_count());
 4957
 4958	trace_netif_rx_entry(skb);
 4959	ret = netif_rx_internal(skb);
 4960	trace_netif_rx_exit(ret);
 4961	return ret;
 4962}
 4963EXPORT_SYMBOL(__netif_rx);
 4964
 4965/**
 4966 *	netif_rx	-	post buffer to the network code
 4967 *	@skb: buffer to post
 4968 *
 4969 *	This function receives a packet from a device driver and queues it for
 4970 *	the upper (protocol) levels to process via the backlog NAPI device. It
 4971 *	always succeeds. The buffer may be dropped during processing for
 4972 *	congestion control or by the protocol layers.
 4973 *	The network buffer is passed via the backlog NAPI device. Modern NIC
 4974 *	driver should use NAPI and GRO.
 4975 *	This function can used from interrupt and from process context. The
 4976 *	caller from process context must not disable interrupts before invoking
 4977 *	this function.
 4978 *
 4979 *	return values:
 4980 *	NET_RX_SUCCESS	(no congestion)
 4981 *	NET_RX_DROP     (packet was dropped)
 4982 *
 4983 */
 4984int netif_rx(struct sk_buff *skb)
 4985{
 4986	bool need_bh_off = !(hardirq_count() | softirq_count());
 4987	int ret;
 4988
 4989	if (need_bh_off)
 4990		local_bh_disable();
 4991	trace_netif_rx_entry(skb);
 4992	ret = netif_rx_internal(skb);
 4993	trace_netif_rx_exit(ret);
 4994	if (need_bh_off)
 4995		local_bh_enable();
 4996	return ret;
 4997}
 4998EXPORT_SYMBOL(netif_rx);
 4999
 5000static __latent_entropy void net_tx_action(struct softirq_action *h)
 5001{
 5002	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
 5003
 5004	if (sd->completion_queue) {
 5005		struct sk_buff *clist;
 5006
 5007		local_irq_disable();
 5008		clist = sd->completion_queue;
 5009		sd->completion_queue = NULL;
 5010		local_irq_enable();
 5011
 5012		while (clist) {
 5013			struct sk_buff *skb = clist;
 5014
 5015			clist = clist->next;
 5016
 5017			WARN_ON(refcount_read(&skb->users));
 5018			if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
 5019				trace_consume_skb(skb);
 5020			else
 5021				trace_kfree_skb(skb, net_tx_action,
 5022						SKB_DROP_REASON_NOT_SPECIFIED);
 5023
 5024			if (skb->fclone != SKB_FCLONE_UNAVAILABLE)
 5025				__kfree_skb(skb);
 5026			else
 5027				__kfree_skb_defer(skb);
 5028		}
 5029	}
 5030
 5031	if (sd->output_queue) {
 5032		struct Qdisc *head;
 5033
 5034		local_irq_disable();
 5035		head = sd->output_queue;
 5036		sd->output_queue = NULL;
 5037		sd->output_queue_tailp = &sd->output_queue;
 5038		local_irq_enable();
 5039
 5040		rcu_read_lock();
 5041
 5042		while (head) {
 5043			struct Qdisc *q = head;
 5044			spinlock_t *root_lock = NULL;
 5045
 5046			head = head->next_sched;
 5047
 5048			/* We need to make sure head->next_sched is read
 5049			 * before clearing __QDISC_STATE_SCHED
 5050			 */
 5051			smp_mb__before_atomic();
 5052
 5053			if (!(q->flags & TCQ_F_NOLOCK)) {
 5054				root_lock = qdisc_lock(q);
 5055				spin_lock(root_lock);
 5056			} else if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED,
 5057						     &q->state))) {
 5058				/* There is a synchronize_net() between
 5059				 * STATE_DEACTIVATED flag being set and
 5060				 * qdisc_reset()/some_qdisc_is_busy() in
 5061				 * dev_deactivate(), so we can safely bail out
 5062				 * early here to avoid data race between
 5063				 * qdisc_deactivate() and some_qdisc_is_busy()
 5064				 * for lockless qdisc.
 5065				 */
 5066				clear_bit(__QDISC_STATE_SCHED, &q->state);
 5067				continue;
 5068			}
 5069
 5070			clear_bit(__QDISC_STATE_SCHED, &q->state);
 5071			qdisc_run(q);
 5072			if (root_lock)
 5073				spin_unlock(root_lock);
 
 
 
 
 
 
 
 
 
 
 5074		}
 5075
 5076		rcu_read_unlock();
 5077	}
 5078
 5079	xfrm_dev_backlog(sd);
 5080}
 5081
 5082#if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE)
 
 5083/* This hook is defined here for ATM LANE */
 5084int (*br_fdb_test_addr_hook)(struct net_device *dev,
 5085			     unsigned char *addr) __read_mostly;
 5086EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
 5087#endif
 5088
 5089static inline struct sk_buff *
 5090sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
 5091		   struct net_device *orig_dev, bool *another)
 5092{
 5093#ifdef CONFIG_NET_CLS_ACT
 5094	struct mini_Qdisc *miniq = rcu_dereference_bh(skb->dev->miniq_ingress);
 5095	struct tcf_result cl_res;
 
 
 
 
 
 
 
 
 
 
 
 
 5096
 5097	/* If there's at least one ingress present somewhere (so
 5098	 * we get here via enabled static key), remaining devices
 5099	 * that are not configured with an ingress qdisc will bail
 5100	 * out here.
 5101	 */
 5102	if (!miniq)
 5103		return skb;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 5104
 5105	if (*pt_prev) {
 5106		*ret = deliver_skb(skb, *pt_prev, orig_dev);
 5107		*pt_prev = NULL;
 5108	}
 5109
 5110	qdisc_skb_cb(skb)->pkt_len = skb->len;
 5111	tc_skb_cb(skb)->mru = 0;
 5112	tc_skb_cb(skb)->post_ct = false;
 5113	skb->tc_at_ingress = 1;
 5114	mini_qdisc_bstats_cpu_update(miniq, skb);
 5115
 5116	switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) {
 5117	case TC_ACT_OK:
 5118	case TC_ACT_RECLASSIFY:
 5119		skb->tc_index = TC_H_MIN(cl_res.classid);
 5120		break;
 5121	case TC_ACT_SHOT:
 5122		mini_qdisc_qstats_cpu_drop(miniq);
 5123		kfree_skb_reason(skb, SKB_DROP_REASON_TC_INGRESS);
 5124		*ret = NET_RX_DROP;
 5125		return NULL;
 5126	case TC_ACT_STOLEN:
 5127	case TC_ACT_QUEUED:
 5128	case TC_ACT_TRAP:
 5129		consume_skb(skb);
 5130		*ret = NET_RX_SUCCESS;
 5131		return NULL;
 5132	case TC_ACT_REDIRECT:
 5133		/* skb_mac_header check was done by cls/act_bpf, so
 5134		 * we can safely push the L2 header back before
 5135		 * redirecting to another netdev
 5136		 */
 5137		__skb_push(skb, skb->mac_len);
 5138		if (skb_do_redirect(skb) == -EAGAIN) {
 5139			__skb_pull(skb, skb->mac_len);
 5140			*another = true;
 5141			break;
 5142		}
 5143		*ret = NET_RX_SUCCESS;
 5144		return NULL;
 5145	case TC_ACT_CONSUMED:
 5146		*ret = NET_RX_SUCCESS;
 5147		return NULL;
 5148	default:
 5149		break;
 5150	}
 5151#endif /* CONFIG_NET_CLS_ACT */
 5152	return skb;
 5153}
 5154
 5155/**
 5156 *	netdev_is_rx_handler_busy - check if receive handler is registered
 5157 *	@dev: device to check
 5158 *
 5159 *	Check if a receive handler is already registered for a given device.
 5160 *	Return true if there one.
 5161 *
 5162 *	The caller must hold the rtnl_mutex.
 5163 */
 5164bool netdev_is_rx_handler_busy(struct net_device *dev)
 5165{
 5166	ASSERT_RTNL();
 5167	return dev && rtnl_dereference(dev->rx_handler);
 5168}
 5169EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy);
 5170
 5171/**
 5172 *	netdev_rx_handler_register - register receive handler
 5173 *	@dev: device to register a handler for
 5174 *	@rx_handler: receive handler to register
 5175 *	@rx_handler_data: data pointer that is used by rx handler
 5176 *
 5177 *	Register a receive handler for a device. This handler will then be
 5178 *	called from __netif_receive_skb. A negative errno code is returned
 5179 *	on a failure.
 5180 *
 5181 *	The caller must hold the rtnl_mutex.
 5182 *
 5183 *	For a general description of rx_handler, see enum rx_handler_result.
 5184 */
 5185int netdev_rx_handler_register(struct net_device *dev,
 5186			       rx_handler_func_t *rx_handler,
 5187			       void *rx_handler_data)
 5188{
 5189	if (netdev_is_rx_handler_busy(dev))
 5190		return -EBUSY;
 5191
 5192	if (dev->priv_flags & IFF_NO_RX_HANDLER)
 5193		return -EINVAL;
 5194
 5195	/* Note: rx_handler_data must be set before rx_handler */
 5196	rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
 5197	rcu_assign_pointer(dev->rx_handler, rx_handler);
 5198
 5199	return 0;
 5200}
 5201EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
 5202
 5203/**
 5204 *	netdev_rx_handler_unregister - unregister receive handler
 5205 *	@dev: device to unregister a handler from
 5206 *
 5207 *	Unregister a receive handler from a device.
 5208 *
 5209 *	The caller must hold the rtnl_mutex.
 5210 */
 5211void netdev_rx_handler_unregister(struct net_device *dev)
 5212{
 5213
 5214	ASSERT_RTNL();
 5215	RCU_INIT_POINTER(dev->rx_handler, NULL);
 5216	/* a reader seeing a non NULL rx_handler in a rcu_read_lock()
 5217	 * section has a guarantee to see a non NULL rx_handler_data
 5218	 * as well.
 5219	 */
 5220	synchronize_net();
 5221	RCU_INIT_POINTER(dev->rx_handler_data, NULL);
 5222}
 5223EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
 5224
 5225/*
 5226 * Limit the use of PFMEMALLOC reserves to those protocols that implement
 5227 * the special handling of PFMEMALLOC skbs.
 5228 */
 5229static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
 5230{
 5231	switch (skb->protocol) {
 5232	case htons(ETH_P_ARP):
 5233	case htons(ETH_P_IP):
 5234	case htons(ETH_P_IPV6):
 5235	case htons(ETH_P_8021Q):
 5236	case htons(ETH_P_8021AD):
 5237		return true;
 5238	default:
 5239		return false;
 5240	}
 5241}
 5242
 5243static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev,
 5244			     int *ret, struct net_device *orig_dev)
 5245{
 5246	if (nf_hook_ingress_active(skb)) {
 5247		int ingress_retval;
 5248
 5249		if (*pt_prev) {
 5250			*ret = deliver_skb(skb, *pt_prev, orig_dev);
 5251			*pt_prev = NULL;
 5252		}
 5253
 5254		rcu_read_lock();
 5255		ingress_retval = nf_hook_ingress(skb);
 5256		rcu_read_unlock();
 5257		return ingress_retval;
 5258	}
 5259	return 0;
 5260}
 5261
 5262static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc,
 5263				    struct packet_type **ppt_prev)
 5264{
 5265	struct packet_type *ptype, *pt_prev;
 5266	rx_handler_func_t *rx_handler;
 5267	struct sk_buff *skb = *pskb;
 5268	struct net_device *orig_dev;
 
 5269	bool deliver_exact = false;
 5270	int ret = NET_RX_DROP;
 5271	__be16 type;
 5272
 5273	net_timestamp_check(!READ_ONCE(netdev_tstamp_prequeue), skb);
 
 5274
 5275	trace_netif_receive_skb(skb);
 5276
 
 
 
 
 
 
 5277	orig_dev = skb->dev;
 5278
 5279	skb_reset_network_header(skb);
 5280	if (!skb_transport_header_was_set(skb))
 5281		skb_reset_transport_header(skb);
 5282	skb_reset_mac_len(skb);
 5283
 5284	pt_prev = NULL;
 5285
 
 
 5286another_round:
 5287	skb->skb_iif = skb->dev->ifindex;
 5288
 5289	__this_cpu_inc(softnet_data.processed);
 5290
 5291	if (static_branch_unlikely(&generic_xdp_needed_key)) {
 5292		int ret2;
 5293
 5294		migrate_disable();
 5295		ret2 = do_xdp_generic(rcu_dereference(skb->dev->xdp_prog), skb);
 5296		migrate_enable();
 5297
 5298		if (ret2 != XDP_PASS) {
 5299			ret = NET_RX_DROP;
 5300			goto out;
 5301		}
 5302	}
 5303
 5304	if (eth_type_vlan(skb->protocol)) {
 5305		skb = skb_vlan_untag(skb);
 5306		if (unlikely(!skb))
 5307			goto out;
 5308	}
 5309
 5310	if (skb_skip_tc_classify(skb))
 5311		goto skip_classify;
 5312
 5313	if (pfmemalloc)
 5314		goto skip_taps;
 5315
 5316	list_for_each_entry_rcu(ptype, &ptype_all, list) {
 5317		if (pt_prev)
 5318			ret = deliver_skb(skb, pt_prev, orig_dev);
 5319		pt_prev = ptype;
 5320	}
 5321
 5322	list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) {
 5323		if (pt_prev)
 5324			ret = deliver_skb(skb, pt_prev, orig_dev);
 5325		pt_prev = ptype;
 5326	}
 5327
 5328skip_taps:
 5329#ifdef CONFIG_NET_INGRESS
 5330	if (static_branch_unlikely(&ingress_needed_key)) {
 5331		bool another = false;
 5332
 5333		nf_skip_egress(skb, true);
 5334		skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev,
 5335					 &another);
 5336		if (another)
 5337			goto another_round;
 5338		if (!skb)
 5339			goto out;
 5340
 5341		nf_skip_egress(skb, false);
 5342		if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0)
 5343			goto out;
 5344	}
 5345#endif
 5346	skb_reset_redirect(skb);
 5347skip_classify:
 5348	if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
 5349		goto drop;
 5350
 5351	if (skb_vlan_tag_present(skb)) {
 5352		if (pt_prev) {
 5353			ret = deliver_skb(skb, pt_prev, orig_dev);
 5354			pt_prev = NULL;
 
 5355		}
 5356		if (vlan_do_receive(&skb))
 5357			goto another_round;
 5358		else if (unlikely(!skb))
 5359			goto out;
 5360	}
 5361
 
 
 
 
 
 
 
 5362	rx_handler = rcu_dereference(skb->dev->rx_handler);
 5363	if (rx_handler) {
 5364		if (pt_prev) {
 5365			ret = deliver_skb(skb, pt_prev, orig_dev);
 5366			pt_prev = NULL;
 5367		}
 5368		switch (rx_handler(&skb)) {
 5369		case RX_HANDLER_CONSUMED:
 5370			ret = NET_RX_SUCCESS;
 5371			goto out;
 5372		case RX_HANDLER_ANOTHER:
 5373			goto another_round;
 5374		case RX_HANDLER_EXACT:
 5375			deliver_exact = true;
 5376			break;
 5377		case RX_HANDLER_PASS:
 5378			break;
 5379		default:
 5380			BUG();
 5381		}
 5382	}
 5383
 5384	if (unlikely(skb_vlan_tag_present(skb)) && !netdev_uses_dsa(skb->dev)) {
 5385check_vlan_id:
 5386		if (skb_vlan_tag_get_id(skb)) {
 5387			/* Vlan id is non 0 and vlan_do_receive() above couldn't
 5388			 * find vlan device.
 5389			 */
 5390			skb->pkt_type = PACKET_OTHERHOST;
 5391		} else if (eth_type_vlan(skb->protocol)) {
 5392			/* Outer header is 802.1P with vlan 0, inner header is
 5393			 * 802.1Q or 802.1AD and vlan_do_receive() above could
 5394			 * not find vlan dev for vlan id 0.
 5395			 */
 5396			__vlan_hwaccel_clear_tag(skb);
 5397			skb = skb_vlan_untag(skb);
 5398			if (unlikely(!skb))
 5399				goto out;
 5400			if (vlan_do_receive(&skb))
 5401				/* After stripping off 802.1P header with vlan 0
 5402				 * vlan dev is found for inner header.
 5403				 */
 5404				goto another_round;
 5405			else if (unlikely(!skb))
 5406				goto out;
 5407			else
 5408				/* We have stripped outer 802.1P vlan 0 header.
 5409				 * But could not find vlan dev.
 5410				 * check again for vlan id to set OTHERHOST.
 5411				 */
 5412				goto check_vlan_id;
 5413		}
 5414		/* Note: we might in the future use prio bits
 5415		 * and set skb->priority like in vlan_do_receive()
 5416		 * For the time being, just ignore Priority Code Point
 5417		 */
 5418		__vlan_hwaccel_clear_tag(skb);
 5419	}
 5420
 5421	type = skb->protocol;
 5422
 5423	/* deliver only exact match when indicated */
 5424	if (likely(!deliver_exact)) {
 5425		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
 5426				       &ptype_base[ntohs(type) &
 5427						   PTYPE_HASH_MASK]);
 5428	}
 5429
 5430	deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
 5431			       &orig_dev->ptype_specific);
 5432
 5433	if (unlikely(skb->dev != orig_dev)) {
 5434		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
 5435				       &skb->dev->ptype_specific);
 
 
 
 
 5436	}
 5437
 5438	if (pt_prev) {
 5439		if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC)))
 5440			goto drop;
 5441		*ppt_prev = pt_prev;
 5442	} else {
 5443drop:
 5444		if (!deliver_exact)
 5445			dev_core_stats_rx_dropped_inc(skb->dev);
 5446		else
 5447			dev_core_stats_rx_nohandler_inc(skb->dev);
 5448		kfree_skb_reason(skb, SKB_DROP_REASON_UNHANDLED_PROTO);
 5449		/* Jamal, now you will not able to escape explaining
 5450		 * me how you were going to use this. :-)
 5451		 */
 5452		ret = NET_RX_DROP;
 5453	}
 5454
 5455out:
 5456	/* The invariant here is that if *ppt_prev is not NULL
 5457	 * then skb should also be non-NULL.
 5458	 *
 5459	 * Apparently *ppt_prev assignment above holds this invariant due to
 5460	 * skb dereferencing near it.
 5461	 */
 5462	*pskb = skb;
 5463	return ret;
 5464}
 5465
 5466static int __netif_receive_skb_one_core(struct sk_buff *skb, bool pfmemalloc)
 5467{
 5468	struct net_device *orig_dev = skb->dev;
 5469	struct packet_type *pt_prev = NULL;
 5470	int ret;
 5471
 5472	ret = __netif_receive_skb_core(&skb, pfmemalloc, &pt_prev);
 5473	if (pt_prev)
 5474		ret = INDIRECT_CALL_INET(pt_prev->func, ipv6_rcv, ip_rcv, skb,
 5475					 skb->dev, pt_prev, orig_dev);
 5476	return ret;
 5477}
 5478
 5479/**
 5480 *	netif_receive_skb_core - special purpose version of netif_receive_skb
 5481 *	@skb: buffer to process
 5482 *
 5483 *	More direct receive version of netif_receive_skb().  It should
 5484 *	only be used by callers that have a need to skip RPS and Generic XDP.
 5485 *	Caller must also take care of handling if ``(page_is_)pfmemalloc``.
 5486 *
 5487 *	This function may only be called from softirq context and interrupts
 5488 *	should be enabled.
 5489 *
 5490 *	Return values (usually ignored):
 5491 *	NET_RX_SUCCESS: no congestion
 5492 *	NET_RX_DROP: packet was dropped
 5493 */
 5494int netif_receive_skb_core(struct sk_buff *skb)
 5495{
 5496	int ret;
 
 5497
 5498	rcu_read_lock();
 5499	ret = __netif_receive_skb_one_core(skb, false);
 5500	rcu_read_unlock();
 5501
 5502	return ret;
 5503}
 5504EXPORT_SYMBOL(netif_receive_skb_core);
 
 5505
 5506static inline void __netif_receive_skb_list_ptype(struct list_head *head,
 5507						  struct packet_type *pt_prev,
 5508						  struct net_device *orig_dev)
 5509{
 5510	struct sk_buff *skb, *next;
 5511
 5512	if (!pt_prev)
 5513		return;
 5514	if (list_empty(head))
 5515		return;
 5516	if (pt_prev->list_func != NULL)
 5517		INDIRECT_CALL_INET(pt_prev->list_func, ipv6_list_rcv,
 5518				   ip_list_rcv, head, pt_prev, orig_dev);
 5519	else
 5520		list_for_each_entry_safe(skb, next, head, list) {
 5521			skb_list_del_init(skb);
 5522			pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
 5523		}
 
 
 
 
 
 
 5524}
 
 5525
 5526static void __netif_receive_skb_list_core(struct list_head *head, bool pfmemalloc)
 5527{
 5528	/* Fast-path assumptions:
 5529	 * - There is no RX handler.
 5530	 * - Only one packet_type matches.
 5531	 * If either of these fails, we will end up doing some per-packet
 5532	 * processing in-line, then handling the 'last ptype' for the whole
 5533	 * sublist.  This can't cause out-of-order delivery to any single ptype,
 5534	 * because the 'last ptype' must be constant across the sublist, and all
 5535	 * other ptypes are handled per-packet.
 5536	 */
 5537	/* Current (common) ptype of sublist */
 5538	struct packet_type *pt_curr = NULL;
 5539	/* Current (common) orig_dev of sublist */
 5540	struct net_device *od_curr = NULL;
 5541	struct list_head sublist;
 5542	struct sk_buff *skb, *next;
 5543
 5544	INIT_LIST_HEAD(&sublist);
 5545	list_for_each_entry_safe(skb, next, head, list) {
 5546		struct net_device *orig_dev = skb->dev;
 5547		struct packet_type *pt_prev = NULL;
 5548
 5549		skb_list_del_init(skb);
 5550		__netif_receive_skb_core(&skb, pfmemalloc, &pt_prev);
 5551		if (!pt_prev)
 5552			continue;
 5553		if (pt_curr != pt_prev || od_curr != orig_dev) {
 5554			/* dispatch old sublist */
 5555			__netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr);
 5556			/* start new sublist */
 5557			INIT_LIST_HEAD(&sublist);
 5558			pt_curr = pt_prev;
 5559			od_curr = orig_dev;
 5560		}
 5561		list_add_tail(&skb->list, &sublist);
 5562	}
 
 5563
 5564	/* dispatch final sublist */
 5565	__netif_receive_skb_list_ptype(&sublist, pt_curr, od_curr);
 
 
 
 
 
 5566}
 5567
 5568static int __netif_receive_skb(struct sk_buff *skb)
 5569{
 5570	int ret;
 
 
 
 5571
 5572	if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
 5573		unsigned int noreclaim_flag;
 
 
 5574
 5575		/*
 5576		 * PFMEMALLOC skbs are special, they should
 5577		 * - be delivered to SOCK_MEMALLOC sockets only
 5578		 * - stay away from userspace
 5579		 * - have bounded memory usage
 5580		 *
 5581		 * Use PF_MEMALLOC as this saves us from propagating the allocation
 5582		 * context down to all allocation sites.
 5583		 */
 5584		noreclaim_flag = memalloc_noreclaim_save();
 5585		ret = __netif_receive_skb_one_core(skb, true);
 5586		memalloc_noreclaim_restore(noreclaim_flag);
 5587	} else
 5588		ret = __netif_receive_skb_one_core(skb, false);
 5589
 5590	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 5591}
 5592
 5593static void __netif_receive_skb_list(struct list_head *head)
 5594{
 5595	unsigned long noreclaim_flag = 0;
 5596	struct sk_buff *skb, *next;
 5597	bool pfmemalloc = false; /* Is current sublist PF_MEMALLOC? */
 5598
 5599	list_for_each_entry_safe(skb, next, head, list) {
 5600		if ((sk_memalloc_socks() && skb_pfmemalloc(skb)) != pfmemalloc) {
 5601			struct list_head sublist;
 5602
 5603			/* Handle the previous sublist */
 5604			list_cut_before(&sublist, head, &skb->list);
 5605			if (!list_empty(&sublist))
 5606				__netif_receive_skb_list_core(&sublist, pfmemalloc);
 5607			pfmemalloc = !pfmemalloc;
 5608			/* See comments in __netif_receive_skb */
 5609			if (pfmemalloc)
 5610				noreclaim_flag = memalloc_noreclaim_save();
 5611			else
 5612				memalloc_noreclaim_restore(noreclaim_flag);
 5613		}
 5614	}
 5615	/* Handle the remaining sublist */
 5616	if (!list_empty(head))
 5617		__netif_receive_skb_list_core(head, pfmemalloc);
 5618	/* Restore pflags */
 5619	if (pfmemalloc)
 5620		memalloc_noreclaim_restore(noreclaim_flag);
 5621}
 
 5622
 5623static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp)
 5624{
 5625	struct bpf_prog *old = rtnl_dereference(dev->xdp_prog);
 5626	struct bpf_prog *new = xdp->prog;
 5627	int ret = 0;
 
 
 
 
 5628
 5629	switch (xdp->command) {
 5630	case XDP_SETUP_PROG:
 5631		rcu_assign_pointer(dev->xdp_prog, new);
 5632		if (old)
 5633			bpf_prog_put(old);
 5634
 5635		if (old && !new) {
 5636			static_branch_dec(&generic_xdp_needed_key);
 5637		} else if (new && !old) {
 5638			static_branch_inc(&generic_xdp_needed_key);
 5639			dev_disable_lro(dev);
 5640			dev_disable_gro_hw(dev);
 5641		}
 5642		break;
 5643
 5644	default:
 5645		ret = -EINVAL;
 
 
 
 
 
 
 
 
 
 
 
 5646		break;
 5647	}
 
 5648
 5649	return ret;
 5650}
 5651
 5652static int netif_receive_skb_internal(struct sk_buff *skb)
 5653{
 5654	int ret;
 5655
 5656	net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
 
 5657
 5658	if (skb_defer_rx_timestamp(skb))
 5659		return NET_RX_SUCCESS;
 
 
 
 5660
 5661	rcu_read_lock();
 5662#ifdef CONFIG_RPS
 5663	if (static_branch_unlikely(&rps_needed)) {
 5664		struct rps_dev_flow voidflow, *rflow = &voidflow;
 5665		int cpu = get_rps_cpu(skb->dev, skb, &rflow);
 5666
 5667		if (cpu >= 0) {
 5668			ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
 5669			rcu_read_unlock();
 5670			return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 5671		}
 5672	}
 5673#endif
 5674	ret = __netif_receive_skb(skb);
 5675	rcu_read_unlock();
 5676	return ret;
 
 
 
 
 5677}
 
 5678
 5679void netif_receive_skb_list_internal(struct list_head *head)
 
 5680{
 5681	struct sk_buff *skb, *next;
 5682	struct list_head sublist;
 5683
 5684	INIT_LIST_HEAD(&sublist);
 5685	list_for_each_entry_safe(skb, next, head, list) {
 5686		net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
 5687		skb_list_del_init(skb);
 5688		if (!skb_defer_rx_timestamp(skb))
 5689			list_add_tail(&skb->list, &sublist);
 5690	}
 5691	list_splice_init(&sublist, head);
 5692
 5693	rcu_read_lock();
 5694#ifdef CONFIG_RPS
 5695	if (static_branch_unlikely(&rps_needed)) {
 5696		list_for_each_entry_safe(skb, next, head, list) {
 5697			struct rps_dev_flow voidflow, *rflow = &voidflow;
 5698			int cpu = get_rps_cpu(skb->dev, skb, &rflow);
 5699
 5700			if (cpu >= 0) {
 5701				/* Will be handled, remove from list */
 5702				skb_list_del_init(skb);
 5703				enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
 5704			}
 5705		}
 5706	}
 5707#endif
 5708	__netif_receive_skb_list(head);
 5709	rcu_read_unlock();
 5710}
 5711
 5712/**
 5713 *	netif_receive_skb - process receive buffer from network
 5714 *	@skb: buffer to process
 5715 *
 5716 *	netif_receive_skb() is the main receive data processing function.
 5717 *	It always succeeds. The buffer may be dropped during processing
 5718 *	for congestion control or by the protocol layers.
 5719 *
 5720 *	This function may only be called from softirq context and interrupts
 5721 *	should be enabled.
 5722 *
 5723 *	Return values (usually ignored):
 5724 *	NET_RX_SUCCESS: no congestion
 5725 *	NET_RX_DROP: packet was dropped
 5726 */
 5727int netif_receive_skb(struct sk_buff *skb)
 5728{
 5729	int ret;
 
 
 
 
 5730
 5731	trace_netif_receive_skb_entry(skb);
 
 
 
 5732
 5733	ret = netif_receive_skb_internal(skb);
 5734	trace_netif_receive_skb_exit(ret);
 
 
 5735
 5736	return ret;
 5737}
 5738EXPORT_SYMBOL(netif_receive_skb);
 5739
 5740/**
 5741 *	netif_receive_skb_list - process many receive buffers from network
 5742 *	@head: list of skbs to process.
 5743 *
 5744 *	Since return value of netif_receive_skb() is normally ignored, and
 5745 *	wouldn't be meaningful for a list, this function returns void.
 5746 *
 5747 *	This function may only be called from softirq context and interrupts
 5748 *	should be enabled.
 5749 */
 5750void netif_receive_skb_list(struct list_head *head)
 5751{
 5752	struct sk_buff *skb;
 
 
 5753
 5754	if (list_empty(head))
 5755		return;
 5756	if (trace_netif_receive_skb_list_entry_enabled()) {
 5757		list_for_each_entry(skb, head, list)
 5758			trace_netif_receive_skb_list_entry(skb);
 
 5759	}
 5760	netif_receive_skb_list_internal(head);
 5761	trace_netif_receive_skb_list_exit(0);
 5762}
 5763EXPORT_SYMBOL(netif_receive_skb_list);
 5764
 5765static DEFINE_PER_CPU(struct work_struct, flush_works);
 
 
 5766
 5767/* Network device is going away, flush any packets still pending */
 5768static void flush_backlog(struct work_struct *work)
 
 
 
 5769{
 5770	struct sk_buff *skb, *tmp;
 5771	struct softnet_data *sd;
 
 
 
 5772
 5773	local_bh_disable();
 5774	sd = this_cpu_ptr(&softnet_data);
 5775
 5776	rps_lock_irq_disable(sd);
 5777	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
 5778		if (skb->dev->reg_state == NETREG_UNREGISTERING) {
 5779			__skb_unlink(skb, &sd->input_pkt_queue);
 5780			dev_kfree_skb_irq(skb);
 5781			input_queue_head_incr(sd);
 5782		}
 5783	}
 5784	rps_unlock_irq_enable(sd);
 5785
 5786	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
 5787		if (skb->dev->reg_state == NETREG_UNREGISTERING) {
 5788			__skb_unlink(skb, &sd->process_queue);
 5789			kfree_skb(skb);
 5790			input_queue_head_incr(sd);
 5791		}
 5792	}
 5793	local_bh_enable();
 5794}
 
 5795
 5796static bool flush_required(int cpu)
 
 5797{
 5798#if IS_ENABLED(CONFIG_RPS)
 5799	struct softnet_data *sd = &per_cpu(softnet_data, cpu);
 5800	bool do_flush;
 
 5801
 5802	rps_lock_irq_disable(sd);
 
 
 
 
 5803
 5804	/* as insertion into process_queue happens with the rps lock held,
 5805	 * process_queue access may race only with dequeue
 5806	 */
 5807	do_flush = !skb_queue_empty(&sd->input_pkt_queue) ||
 5808		   !skb_queue_empty_lockless(&sd->process_queue);
 5809	rps_unlock_irq_enable(sd);
 5810
 5811	return do_flush;
 5812#endif
 5813	/* without RPS we can't safely check input_pkt_queue: during a
 5814	 * concurrent remote skb_queue_splice() we can detect as empty both
 5815	 * input_pkt_queue and process_queue even if the latter could end-up
 5816	 * containing a lot of packets.
 5817	 */
 5818	return true;
 5819}
 
 5820
 5821static void flush_all_backlogs(void)
 5822{
 5823	static cpumask_t flush_cpus;
 5824	unsigned int cpu;
 
 
 5825
 5826	/* since we are under rtnl lock protection we can use static data
 5827	 * for the cpumask and avoid allocating on stack the possibly
 5828	 * large mask
 5829	 */
 5830	ASSERT_RTNL();
 5831
 5832	cpus_read_lock();
 
 5833
 5834	cpumask_clear(&flush_cpus);
 5835	for_each_online_cpu(cpu) {
 5836		if (flush_required(cpu)) {
 5837			queue_work_on(cpu, system_highpri_wq,
 5838				      per_cpu_ptr(&flush_works, cpu));
 5839			cpumask_set_cpu(cpu, &flush_cpus);
 
 
 
 5840		}
 5841	}
 5842
 5843	/* we can have in flight packet[s] on the cpus we are not flushing,
 5844	 * synchronize_net() in unregister_netdevice_many() will take care of
 5845	 * them
 
 
 5846	 */
 5847	for_each_cpu(cpu, &flush_cpus)
 5848		flush_work(per_cpu_ptr(&flush_works, cpu));
 5849
 5850	cpus_read_unlock();
 
 5851}
 
 5852
 5853static void net_rps_send_ipi(struct softnet_data *remsd)
 5854{
 5855#ifdef CONFIG_RPS
 5856	while (remsd) {
 5857		struct softnet_data *next = remsd->rps_ipi_next;
 5858
 5859		if (cpu_online(remsd->cpu))
 5860			smp_call_function_single_async(remsd->cpu, &remsd->csd);
 5861		remsd = next;
 5862	}
 5863#endif
 5864}
 
 5865
 5866/*
 5867 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
 5868 * Note: called with local irq disabled, but exits with local irq enabled.
 5869 */
 5870static void net_rps_action_and_irq_enable(struct softnet_data *sd)
 5871{
 5872#ifdef CONFIG_RPS
 5873	struct softnet_data *remsd = sd->rps_ipi_list;
 5874
 5875	if (remsd) {
 5876		sd->rps_ipi_list = NULL;
 5877
 5878		local_irq_enable();
 5879
 5880		/* Send pending IPI's to kick RPS processing on remote cpus. */
 5881		net_rps_send_ipi(remsd);
 
 
 
 
 
 
 
 5882	} else
 5883#endif
 5884		local_irq_enable();
 5885}
 5886
 5887static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
 5888{
 5889#ifdef CONFIG_RPS
 5890	return sd->rps_ipi_list != NULL;
 5891#else
 5892	return false;
 5893#endif
 5894}
 5895
 5896static int process_backlog(struct napi_struct *napi, int quota)
 5897{
 5898	struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
 5899	bool again = true;
 5900	int work = 0;
 
 5901
 
 5902	/* Check if we have pending ipi, its better to send them now,
 5903	 * not waiting net_rx_action() end.
 5904	 */
 5905	if (sd_has_rps_ipi_waiting(sd)) {
 5906		local_irq_disable();
 5907		net_rps_action_and_irq_enable(sd);
 5908	}
 5909
 5910	napi->weight = READ_ONCE(dev_rx_weight);
 5911	while (again) {
 
 5912		struct sk_buff *skb;
 
 5913
 5914		while ((skb = __skb_dequeue(&sd->process_queue))) {
 5915			rcu_read_lock();
 5916			__netif_receive_skb(skb);
 5917			rcu_read_unlock();
 5918			input_queue_head_incr(sd);
 5919			if (++work >= quota)
 
 5920				return work;
 5921
 5922		}
 5923
 5924		rps_lock_irq_disable(sd);
 5925		if (skb_queue_empty(&sd->input_pkt_queue)) {
 
 
 
 
 
 5926			/*
 5927			 * Inline a custom version of __napi_complete().
 5928			 * only current cpu owns and manipulates this napi,
 5929			 * and NAPI_STATE_SCHED is the only possible flag set
 5930			 * on backlog.
 5931			 * We can use a plain write instead of clear_bit(),
 5932			 * and we dont need an smp_mb() memory barrier.
 5933			 */
 
 5934			napi->state = 0;
 5935			again = false;
 5936		} else {
 5937			skb_queue_splice_tail_init(&sd->input_pkt_queue,
 5938						   &sd->process_queue);
 5939		}
 5940		rps_unlock_irq_enable(sd);
 5941	}
 
 5942
 5943	return work;
 5944}
 5945
 5946/**
 5947 * __napi_schedule - schedule for receive
 5948 * @n: entry to schedule
 5949 *
 5950 * The entry's receive function will be scheduled to run.
 5951 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
 5952 */
 5953void __napi_schedule(struct napi_struct *n)
 5954{
 5955	unsigned long flags;
 5956
 5957	local_irq_save(flags);
 5958	____napi_schedule(this_cpu_ptr(&softnet_data), n);
 5959	local_irq_restore(flags);
 5960}
 5961EXPORT_SYMBOL(__napi_schedule);
 5962
 5963/**
 5964 *	napi_schedule_prep - check if napi can be scheduled
 5965 *	@n: napi context
 5966 *
 5967 * Test if NAPI routine is already running, and if not mark
 5968 * it as running.  This is used as a condition variable to
 5969 * insure only one NAPI poll instance runs.  We also make
 5970 * sure there is no pending NAPI disable.
 5971 */
 5972bool napi_schedule_prep(struct napi_struct *n)
 5973{
 5974	unsigned long new, val = READ_ONCE(n->state);
 5975
 5976	do {
 5977		if (unlikely(val & NAPIF_STATE_DISABLE))
 5978			return false;
 5979		new = val | NAPIF_STATE_SCHED;
 5980
 5981		/* Sets STATE_MISSED bit if STATE_SCHED was already set
 5982		 * This was suggested by Alexander Duyck, as compiler
 5983		 * emits better code than :
 5984		 * if (val & NAPIF_STATE_SCHED)
 5985		 *     new |= NAPIF_STATE_MISSED;
 5986		 */
 5987		new |= (val & NAPIF_STATE_SCHED) / NAPIF_STATE_SCHED *
 5988						   NAPIF_STATE_MISSED;
 5989	} while (!try_cmpxchg(&n->state, &val, new));
 5990
 5991	return !(val & NAPIF_STATE_SCHED);
 5992}
 5993EXPORT_SYMBOL(napi_schedule_prep);
 5994
 5995/**
 5996 * __napi_schedule_irqoff - schedule for receive
 5997 * @n: entry to schedule
 5998 *
 5999 * Variant of __napi_schedule() assuming hard irqs are masked.
 6000 *
 6001 * On PREEMPT_RT enabled kernels this maps to __napi_schedule()
 6002 * because the interrupt disabled assumption might not be true
 6003 * due to force-threaded interrupts and spinlock substitution.
 6004 */
 6005void __napi_schedule_irqoff(struct napi_struct *n)
 6006{
 6007	if (!IS_ENABLED(CONFIG_PREEMPT_RT))
 6008		____napi_schedule(this_cpu_ptr(&softnet_data), n);
 6009	else
 6010		__napi_schedule(n);
 6011}
 6012EXPORT_SYMBOL(__napi_schedule_irqoff);
 6013
 6014bool napi_complete_done(struct napi_struct *n, int work_done)
 6015{
 6016	unsigned long flags, val, new, timeout = 0;
 6017	bool ret = true;
 6018
 6019	/*
 6020	 * 1) Don't let napi dequeue from the cpu poll list
 6021	 *    just in case its running on a different cpu.
 6022	 * 2) If we are busy polling, do nothing here, we have
 6023	 *    the guarantee we will be called later.
 6024	 */
 6025	if (unlikely(n->state & (NAPIF_STATE_NPSVC |
 6026				 NAPIF_STATE_IN_BUSY_POLL)))
 6027		return false;
 6028
 6029	if (work_done) {
 6030		if (n->gro_bitmask)
 6031			timeout = READ_ONCE(n->dev->gro_flush_timeout);
 6032		n->defer_hard_irqs_count = READ_ONCE(n->dev->napi_defer_hard_irqs);
 6033	}
 6034	if (n->defer_hard_irqs_count > 0) {
 6035		n->defer_hard_irqs_count--;
 6036		timeout = READ_ONCE(n->dev->gro_flush_timeout);
 6037		if (timeout)
 6038			ret = false;
 6039	}
 6040	if (n->gro_bitmask) {
 6041		/* When the NAPI instance uses a timeout and keeps postponing
 6042		 * it, we need to bound somehow the time packets are kept in
 6043		 * the GRO layer
 6044		 */
 6045		napi_gro_flush(n, !!timeout);
 6046	}
 6047
 6048	gro_normal_list(n);
 6049
 6050	if (unlikely(!list_empty(&n->poll_list))) {
 6051		/* If n->poll_list is not empty, we need to mask irqs */
 6052		local_irq_save(flags);
 6053		list_del_init(&n->poll_list);
 6054		local_irq_restore(flags);
 6055	}
 6056
 6057	val = READ_ONCE(n->state);
 6058	do {
 6059		WARN_ON_ONCE(!(val & NAPIF_STATE_SCHED));
 6060
 6061		new = val & ~(NAPIF_STATE_MISSED | NAPIF_STATE_SCHED |
 6062			      NAPIF_STATE_SCHED_THREADED |
 6063			      NAPIF_STATE_PREFER_BUSY_POLL);
 6064
 6065		/* If STATE_MISSED was set, leave STATE_SCHED set,
 6066		 * because we will call napi->poll() one more time.
 6067		 * This C code was suggested by Alexander Duyck to help gcc.
 6068		 */
 6069		new |= (val & NAPIF_STATE_MISSED) / NAPIF_STATE_MISSED *
 6070						    NAPIF_STATE_SCHED;
 6071	} while (!try_cmpxchg(&n->state, &val, new));
 6072
 6073	if (unlikely(val & NAPIF_STATE_MISSED)) {
 6074		__napi_schedule(n);
 6075		return false;
 6076	}
 6077
 6078	if (timeout)
 6079		hrtimer_start(&n->timer, ns_to_ktime(timeout),
 6080			      HRTIMER_MODE_REL_PINNED);
 6081	return ret;
 6082}
 6083EXPORT_SYMBOL(napi_complete_done);
 6084
 6085/* must be called under rcu_read_lock(), as we dont take a reference */
 6086static struct napi_struct *napi_by_id(unsigned int napi_id)
 6087{
 6088	unsigned int hash = napi_id % HASH_SIZE(napi_hash);
 6089	struct napi_struct *napi;
 6090
 6091	hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
 6092		if (napi->napi_id == napi_id)
 6093			return napi;
 6094
 6095	return NULL;
 6096}
 6097
 6098#if defined(CONFIG_NET_RX_BUSY_POLL)
 6099
 6100static void __busy_poll_stop(struct napi_struct *napi, bool skip_schedule)
 6101{
 6102	if (!skip_schedule) {
 6103		gro_normal_list(napi);
 6104		__napi_schedule(napi);
 6105		return;
 6106	}
 6107
 6108	if (napi->gro_bitmask) {
 6109		/* flush too old packets
 6110		 * If HZ < 1000, flush all packets.
 6111		 */
 6112		napi_gro_flush(napi, HZ >= 1000);
 6113	}
 6114
 6115	gro_normal_list(napi);
 6116	clear_bit(NAPI_STATE_SCHED, &napi->state);
 6117}
 6118
 6119static void busy_poll_stop(struct napi_struct *napi, void *have_poll_lock, bool prefer_busy_poll,
 6120			   u16 budget)
 6121{
 6122	bool skip_schedule = false;
 6123	unsigned long timeout;
 6124	int rc;
 6125
 6126	/* Busy polling means there is a high chance device driver hard irq
 6127	 * could not grab NAPI_STATE_SCHED, and that NAPI_STATE_MISSED was
 6128	 * set in napi_schedule_prep().
 6129	 * Since we are about to call napi->poll() once more, we can safely
 6130	 * clear NAPI_STATE_MISSED.
 6131	 *
 6132	 * Note: x86 could use a single "lock and ..." instruction
 6133	 * to perform these two clear_bit()
 6134	 */
 6135	clear_bit(NAPI_STATE_MISSED, &napi->state);
 6136	clear_bit(NAPI_STATE_IN_BUSY_POLL, &napi->state);
 6137
 6138	local_bh_disable();
 6139
 6140	if (prefer_busy_poll) {
 6141		napi->defer_hard_irqs_count = READ_ONCE(napi->dev->napi_defer_hard_irqs);
 6142		timeout = READ_ONCE(napi->dev->gro_flush_timeout);
 6143		if (napi->defer_hard_irqs_count && timeout) {
 6144			hrtimer_start(&napi->timer, ns_to_ktime(timeout), HRTIMER_MODE_REL_PINNED);
 6145			skip_schedule = true;
 6146		}
 6147	}
 6148
 6149	/* All we really want here is to re-enable device interrupts.
 6150	 * Ideally, a new ndo_busy_poll_stop() could avoid another round.
 6151	 */
 6152	rc = napi->poll(napi, budget);
 6153	/* We can't gro_normal_list() here, because napi->poll() might have
 6154	 * rearmed the napi (napi_complete_done()) in which case it could
 6155	 * already be running on another CPU.
 6156	 */
 6157	trace_napi_poll(napi, rc, budget);
 6158	netpoll_poll_unlock(have_poll_lock);
 6159	if (rc == budget)
 6160		__busy_poll_stop(napi, skip_schedule);
 6161	local_bh_enable();
 6162}
 6163
 6164void napi_busy_loop(unsigned int napi_id,
 6165		    bool (*loop_end)(void *, unsigned long),
 6166		    void *loop_end_arg, bool prefer_busy_poll, u16 budget)
 6167{
 6168	unsigned long start_time = loop_end ? busy_loop_current_time() : 0;
 6169	int (*napi_poll)(struct napi_struct *napi, int budget);
 6170	void *have_poll_lock = NULL;
 6171	struct napi_struct *napi;
 6172
 6173restart:
 6174	napi_poll = NULL;
 6175
 6176	rcu_read_lock();
 6177
 6178	napi = napi_by_id(napi_id);
 6179	if (!napi)
 6180		goto out;
 6181
 6182	preempt_disable();
 6183	for (;;) {
 6184		int work = 0;
 6185
 6186		local_bh_disable();
 6187		if (!napi_poll) {
 6188			unsigned long val = READ_ONCE(napi->state);
 6189
 6190			/* If multiple threads are competing for this napi,
 6191			 * we avoid dirtying napi->state as much as we can.
 6192			 */
 6193			if (val & (NAPIF_STATE_DISABLE | NAPIF_STATE_SCHED |
 6194				   NAPIF_STATE_IN_BUSY_POLL)) {
 6195				if (prefer_busy_poll)
 6196					set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state);
 6197				goto count;
 6198			}
 6199			if (cmpxchg(&napi->state, val,
 6200				    val | NAPIF_STATE_IN_BUSY_POLL |
 6201					  NAPIF_STATE_SCHED) != val) {
 6202				if (prefer_busy_poll)
 6203					set_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state);
 6204				goto count;
 6205			}
 6206			have_poll_lock = netpoll_poll_lock(napi);
 6207			napi_poll = napi->poll;
 6208		}
 6209		work = napi_poll(napi, budget);
 6210		trace_napi_poll(napi, work, budget);
 6211		gro_normal_list(napi);
 6212count:
 6213		if (work > 0)
 6214			__NET_ADD_STATS(dev_net(napi->dev),
 6215					LINUX_MIB_BUSYPOLLRXPACKETS, work);
 6216		local_bh_enable();
 6217
 6218		if (!loop_end || loop_end(loop_end_arg, start_time))
 6219			break;
 6220
 6221		if (unlikely(need_resched())) {
 6222			if (napi_poll)
 6223				busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget);
 6224			preempt_enable();
 6225			rcu_read_unlock();
 6226			cond_resched();
 6227			if (loop_end(loop_end_arg, start_time))
 6228				return;
 6229			goto restart;
 6230		}
 6231		cpu_relax();
 6232	}
 6233	if (napi_poll)
 6234		busy_poll_stop(napi, have_poll_lock, prefer_busy_poll, budget);
 6235	preempt_enable();
 6236out:
 6237	rcu_read_unlock();
 6238}
 6239EXPORT_SYMBOL(napi_busy_loop);
 6240
 6241#endif /* CONFIG_NET_RX_BUSY_POLL */
 6242
 6243static void napi_hash_add(struct napi_struct *napi)
 6244{
 6245	if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state))
 6246		return;
 6247
 6248	spin_lock(&napi_hash_lock);
 6249
 6250	/* 0..NR_CPUS range is reserved for sender_cpu use */
 6251	do {
 6252		if (unlikely(++napi_gen_id < MIN_NAPI_ID))
 6253			napi_gen_id = MIN_NAPI_ID;
 6254	} while (napi_by_id(napi_gen_id));
 6255	napi->napi_id = napi_gen_id;
 6256
 6257	hlist_add_head_rcu(&napi->napi_hash_node,
 6258			   &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
 6259
 6260	spin_unlock(&napi_hash_lock);
 6261}
 6262
 6263/* Warning : caller is responsible to make sure rcu grace period
 6264 * is respected before freeing memory containing @napi
 6265 */
 6266static void napi_hash_del(struct napi_struct *napi)
 6267{
 6268	spin_lock(&napi_hash_lock);
 6269
 6270	hlist_del_init_rcu(&napi->napi_hash_node);
 6271
 6272	spin_unlock(&napi_hash_lock);
 6273}
 6274
 6275static enum hrtimer_restart napi_watchdog(struct hrtimer *timer)
 6276{
 6277	struct napi_struct *napi;
 6278
 6279	napi = container_of(timer, struct napi_struct, timer);
 6280
 6281	/* Note : we use a relaxed variant of napi_schedule_prep() not setting
 6282	 * NAPI_STATE_MISSED, since we do not react to a device IRQ.
 6283	 */
 6284	if (!napi_disable_pending(napi) &&
 6285	    !test_and_set_bit(NAPI_STATE_SCHED, &napi->state)) {
 6286		clear_bit(NAPI_STATE_PREFER_BUSY_POLL, &napi->state);
 6287		__napi_schedule_irqoff(napi);
 6288	}
 6289
 6290	return HRTIMER_NORESTART;
 6291}
 6292
 6293static void init_gro_hash(struct napi_struct *napi)
 6294{
 6295	int i;
 6296
 6297	for (i = 0; i < GRO_HASH_BUCKETS; i++) {
 6298		INIT_LIST_HEAD(&napi->gro_hash[i].list);
 6299		napi->gro_hash[i].count = 0;
 6300	}
 6301	napi->gro_bitmask = 0;
 6302}
 6303
 6304int dev_set_threaded(struct net_device *dev, bool threaded)
 6305{
 6306	struct napi_struct *napi;
 6307	int err = 0;
 6308
 6309	if (dev->threaded == threaded)
 6310		return 0;
 6311
 6312	if (threaded) {
 6313		list_for_each_entry(napi, &dev->napi_list, dev_list) {
 6314			if (!napi->thread) {
 6315				err = napi_kthread_create(napi);
 6316				if (err) {
 6317					threaded = false;
 6318					break;
 6319				}
 6320			}
 6321		}
 6322	}
 6323
 6324	dev->threaded = threaded;
 6325
 6326	/* Make sure kthread is created before THREADED bit
 6327	 * is set.
 6328	 */
 6329	smp_mb__before_atomic();
 6330
 6331	/* Setting/unsetting threaded mode on a napi might not immediately
 6332	 * take effect, if the current napi instance is actively being
 6333	 * polled. In this case, the switch between threaded mode and
 6334	 * softirq mode will happen in the next round of napi_schedule().
 6335	 * This should not cause hiccups/stalls to the live traffic.
 6336	 */
 6337	list_for_each_entry(napi, &dev->napi_list, dev_list) {
 6338		if (threaded)
 6339			set_bit(NAPI_STATE_THREADED, &napi->state);
 6340		else
 6341			clear_bit(NAPI_STATE_THREADED, &napi->state);
 6342	}
 6343
 6344	return err;
 6345}
 6346EXPORT_SYMBOL(dev_set_threaded);
 6347
 6348void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi,
 6349			   int (*poll)(struct napi_struct *, int), int weight)
 6350{
 6351	if (WARN_ON(test_and_set_bit(NAPI_STATE_LISTED, &napi->state)))
 6352		return;
 6353
 6354	INIT_LIST_HEAD(&napi->poll_list);
 6355	INIT_HLIST_NODE(&napi->napi_hash_node);
 6356	hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
 6357	napi->timer.function = napi_watchdog;
 6358	init_gro_hash(napi);
 6359	napi->skb = NULL;
 6360	INIT_LIST_HEAD(&napi->rx_list);
 6361	napi->rx_count = 0;
 6362	napi->poll = poll;
 6363	if (weight > NAPI_POLL_WEIGHT)
 6364		netdev_err_once(dev, "%s() called with weight %d\n", __func__,
 6365				weight);
 6366	napi->weight = weight;
 
 6367	napi->dev = dev;
 6368#ifdef CONFIG_NETPOLL
 
 6369	napi->poll_owner = -1;
 6370#endif
 6371	set_bit(NAPI_STATE_SCHED, &napi->state);
 6372	set_bit(NAPI_STATE_NPSVC, &napi->state);
 6373	list_add_rcu(&napi->dev_list, &dev->napi_list);
 6374	napi_hash_add(napi);
 6375	napi_get_frags_check(napi);
 6376	/* Create kthread for this napi if dev->threaded is set.
 6377	 * Clear dev->threaded if kthread creation failed so that
 6378	 * threaded mode will not be enabled in napi_enable().
 6379	 */
 6380	if (dev->threaded && napi_kthread_create(napi))
 6381		dev->threaded = 0;
 6382}
 6383EXPORT_SYMBOL(netif_napi_add_weight);
 6384
 6385void napi_disable(struct napi_struct *n)
 6386{
 6387	unsigned long val, new;
 6388
 6389	might_sleep();
 6390	set_bit(NAPI_STATE_DISABLE, &n->state);
 6391
 6392	val = READ_ONCE(n->state);
 6393	do {
 6394		while (val & (NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC)) {
 6395			usleep_range(20, 200);
 6396			val = READ_ONCE(n->state);
 6397		}
 6398
 6399		new = val | NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC;
 6400		new &= ~(NAPIF_STATE_THREADED | NAPIF_STATE_PREFER_BUSY_POLL);
 6401	} while (!try_cmpxchg(&n->state, &val, new));
 6402
 6403	hrtimer_cancel(&n->timer);
 6404
 6405	clear_bit(NAPI_STATE_DISABLE, &n->state);
 6406}
 6407EXPORT_SYMBOL(napi_disable);
 6408
 6409/**
 6410 *	napi_enable - enable NAPI scheduling
 6411 *	@n: NAPI context
 6412 *
 6413 * Resume NAPI from being scheduled on this context.
 6414 * Must be paired with napi_disable.
 6415 */
 6416void napi_enable(struct napi_struct *n)
 6417{
 6418	unsigned long new, val = READ_ONCE(n->state);
 6419
 6420	do {
 6421		BUG_ON(!test_bit(NAPI_STATE_SCHED, &val));
 6422
 6423		new = val & ~(NAPIF_STATE_SCHED | NAPIF_STATE_NPSVC);
 6424		if (n->dev->threaded && n->thread)
 6425			new |= NAPIF_STATE_THREADED;
 6426	} while (!try_cmpxchg(&n->state, &val, new));
 6427}
 6428EXPORT_SYMBOL(napi_enable);
 6429
 6430static void flush_gro_hash(struct napi_struct *napi)
 6431{
 6432	int i;
 6433
 6434	for (i = 0; i < GRO_HASH_BUCKETS; i++) {
 6435		struct sk_buff *skb, *n;
 6436
 6437		list_for_each_entry_safe(skb, n, &napi->gro_hash[i].list, list)
 6438			kfree_skb(skb);
 6439		napi->gro_hash[i].count = 0;
 6440	}
 6441}
 
 6442
 6443/* Must be called in process context */
 6444void __netif_napi_del(struct napi_struct *napi)
 6445{
 6446	if (!test_and_clear_bit(NAPI_STATE_LISTED, &napi->state))
 6447		return;
 6448
 6449	napi_hash_del(napi);
 6450	list_del_rcu(&napi->dev_list);
 6451	napi_free_frags(napi);
 6452
 6453	flush_gro_hash(napi);
 6454	napi->gro_bitmask = 0;
 6455
 6456	if (napi->thread) {
 6457		kthread_stop(napi->thread);
 6458		napi->thread = NULL;
 6459	}
 6460}
 6461EXPORT_SYMBOL(__netif_napi_del);
 6462
 6463static int __napi_poll(struct napi_struct *n, bool *repoll)
 6464{
 6465	int work, weight;
 6466
 6467	weight = n->weight;
 6468
 6469	/* This NAPI_STATE_SCHED test is for avoiding a race
 6470	 * with netpoll's poll_napi().  Only the entity which
 6471	 * obtains the lock and sees NAPI_STATE_SCHED set will
 6472	 * actually make the ->poll() call.  Therefore we avoid
 6473	 * accidentally calling ->poll() when NAPI is not scheduled.
 6474	 */
 6475	work = 0;
 6476	if (test_bit(NAPI_STATE_SCHED, &n->state)) {
 6477		work = n->poll(n, weight);
 6478		trace_napi_poll(n, work, weight);
 6479	}
 6480
 6481	if (unlikely(work > weight))
 6482		netdev_err_once(n->dev, "NAPI poll function %pS returned %d, exceeding its budget of %d.\n",
 6483				n->poll, work, weight);
 6484
 6485	if (likely(work < weight))
 6486		return work;
 6487
 6488	/* Drivers must not modify the NAPI state if they
 6489	 * consume the entire weight.  In such cases this code
 6490	 * still "owns" the NAPI instance and therefore can
 6491	 * move the instance around on the list at-will.
 6492	 */
 6493	if (unlikely(napi_disable_pending(n))) {
 6494		napi_complete(n);
 6495		return work;
 6496	}
 6497
 6498	/* The NAPI context has more processing work, but busy-polling
 6499	 * is preferred. Exit early.
 6500	 */
 6501	if (napi_prefer_busy_poll(n)) {
 6502		if (napi_complete_done(n, work)) {
 6503			/* If timeout is not set, we need to make sure
 6504			 * that the NAPI is re-scheduled.
 6505			 */
 6506			napi_schedule(n);
 6507		}
 6508		return work;
 6509	}
 6510
 6511	if (n->gro_bitmask) {
 6512		/* flush too old packets
 6513		 * If HZ < 1000, flush all packets.
 6514		 */
 6515		napi_gro_flush(n, HZ >= 1000);
 6516	}
 6517
 6518	gro_normal_list(n);
 6519
 6520	/* Some drivers may have called napi_schedule
 6521	 * prior to exhausting their budget.
 6522	 */
 6523	if (unlikely(!list_empty(&n->poll_list))) {
 6524		pr_warn_once("%s: Budget exhausted after napi rescheduled\n",
 6525			     n->dev ? n->dev->name : "backlog");
 6526		return work;
 6527	}
 6528
 6529	*repoll = true;
 6530
 6531	return work;
 6532}
 6533
 6534static int napi_poll(struct napi_struct *n, struct list_head *repoll)
 6535{
 6536	bool do_repoll = false;
 6537	void *have;
 6538	int work;
 6539
 6540	list_del_init(&n->poll_list);
 6541
 6542	have = netpoll_poll_lock(n);
 6543
 6544	work = __napi_poll(n, &do_repoll);
 6545
 6546	if (do_repoll)
 6547		list_add_tail(&n->poll_list, repoll);
 6548
 6549	netpoll_poll_unlock(have);
 6550
 6551	return work;
 6552}
 6553
 6554static int napi_thread_wait(struct napi_struct *napi)
 6555{
 6556	bool woken = false;
 6557
 6558	set_current_state(TASK_INTERRUPTIBLE);
 6559
 6560	while (!kthread_should_stop()) {
 6561		/* Testing SCHED_THREADED bit here to make sure the current
 6562		 * kthread owns this napi and could poll on this napi.
 6563		 * Testing SCHED bit is not enough because SCHED bit might be
 6564		 * set by some other busy poll thread or by napi_disable().
 6565		 */
 6566		if (test_bit(NAPI_STATE_SCHED_THREADED, &napi->state) || woken) {
 6567			WARN_ON(!list_empty(&napi->poll_list));
 6568			__set_current_state(TASK_RUNNING);
 6569			return 0;
 6570		}
 6571
 6572		schedule();
 6573		/* woken being true indicates this thread owns this napi. */
 6574		woken = true;
 6575		set_current_state(TASK_INTERRUPTIBLE);
 6576	}
 6577	__set_current_state(TASK_RUNNING);
 6578
 6579	return -1;
 
 6580}
 
 6581
 6582static int napi_threaded_poll(void *data)
 6583{
 6584	struct napi_struct *napi = data;
 
 
 6585	void *have;
 6586
 6587	while (!napi_thread_wait(napi)) {
 6588		for (;;) {
 6589			bool repoll = false;
 6590
 6591			local_bh_disable();
 6592
 6593			have = netpoll_poll_lock(napi);
 6594			__napi_poll(napi, &repoll);
 6595			netpoll_poll_unlock(have);
 6596
 6597			local_bh_enable();
 6598
 6599			if (!repoll)
 6600				break;
 6601
 6602			cond_resched();
 6603		}
 6604	}
 6605	return 0;
 6606}
 6607
 6608static void skb_defer_free_flush(struct softnet_data *sd)
 6609{
 6610	struct sk_buff *skb, *next;
 6611	unsigned long flags;
 6612
 6613	/* Paired with WRITE_ONCE() in skb_attempt_defer_free() */
 6614	if (!READ_ONCE(sd->defer_list))
 6615		return;
 6616
 6617	spin_lock_irqsave(&sd->defer_lock, flags);
 6618	skb = sd->defer_list;
 6619	sd->defer_list = NULL;
 6620	sd->defer_count = 0;
 6621	spin_unlock_irqrestore(&sd->defer_lock, flags);
 6622
 6623	while (skb != NULL) {
 6624		next = skb->next;
 6625		napi_consume_skb(skb, 1);
 6626		skb = next;
 6627	}
 6628}
 6629
 6630static __latent_entropy void net_rx_action(struct softirq_action *h)
 6631{
 6632	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
 6633	unsigned long time_limit = jiffies +
 6634		usecs_to_jiffies(READ_ONCE(netdev_budget_usecs));
 6635	int budget = READ_ONCE(netdev_budget);
 6636	LIST_HEAD(list);
 6637	LIST_HEAD(repoll);
 6638
 6639	local_irq_disable();
 6640	list_splice_init(&sd->poll_list, &list);
 6641	local_irq_enable();
 6642
 6643	for (;;) {
 6644		struct napi_struct *n;
 
 6645
 6646		skb_defer_free_flush(sd);
 6647
 6648		if (list_empty(&list)) {
 6649			if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
 6650				goto end;
 6651			break;
 6652		}
 6653
 6654		n = list_first_entry(&list, struct napi_struct, poll_list);
 6655		budget -= napi_poll(n, &repoll);
 6656
 6657		/* If softirq window is exhausted then punt.
 6658		 * Allow this to run for 2 jiffies since which will allow
 6659		 * an average latency of 1.5/HZ.
 6660		 */
 6661		if (unlikely(budget <= 0 ||
 6662			     time_after_eq(jiffies, time_limit))) {
 6663			sd->time_squeeze++;
 6664			break;
 6665		}
 6666	}
 6667
 6668	local_irq_disable();
 6669
 6670	list_splice_tail_init(&sd->poll_list, &list);
 6671	list_splice_tail(&repoll, &list);
 6672	list_splice(&list, &sd->poll_list);
 6673	if (!list_empty(&sd->poll_list))
 6674		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
 6675
 6676	net_rps_action_and_irq_enable(sd);
 6677end:;
 6678}
 
 
 
 6679
 6680struct netdev_adjacent {
 6681	struct net_device *dev;
 6682	netdevice_tracker dev_tracker;
 6683
 6684	/* upper master flag, there can only be one master device per list */
 6685	bool master;
 6686
 6687	/* lookup ignore flag */
 6688	bool ignore;
 
 
 
 
 
 
 
 
 
 6689
 6690	/* counter for the number of times this device was added to us */
 6691	u16 ref_nr;
 6692
 6693	/* private field for the users */
 6694	void *private;
 6695
 6696	struct list_head list;
 6697	struct rcu_head rcu;
 6698};
 6699
 6700static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev,
 6701						 struct list_head *adj_list)
 6702{
 6703	struct netdev_adjacent *adj;
 
 
 
 
 
 
 
 
 
 6704
 6705	list_for_each_entry(adj, adj_list, list) {
 6706		if (adj->dev == adj_dev)
 6707			return adj;
 6708	}
 6709	return NULL;
 6710}
 6711
 6712static int ____netdev_has_upper_dev(struct net_device *upper_dev,
 6713				    struct netdev_nested_priv *priv)
 6714{
 6715	struct net_device *dev = (struct net_device *)priv->data;
 6716
 6717	return upper_dev == dev;
 6718}
 6719
 6720/**
 6721 * netdev_has_upper_dev - Check if device is linked to an upper device
 6722 * @dev: device
 6723 * @upper_dev: upper device to check
 6724 *
 6725 * Find out if a device is linked to specified upper device and return true
 6726 * in case it is. Note that this checks only immediate upper device,
 6727 * not through a complete stack of devices. The caller must hold the RTNL lock.
 6728 */
 6729bool netdev_has_upper_dev(struct net_device *dev,
 6730			  struct net_device *upper_dev)
 6731{
 6732	struct netdev_nested_priv priv = {
 6733		.data = (void *)upper_dev,
 6734	};
 6735
 6736	ASSERT_RTNL();
 6737
 6738	return netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev,
 6739					     &priv);
 6740}
 6741EXPORT_SYMBOL(netdev_has_upper_dev);
 6742
 6743/**
 6744 * netdev_has_upper_dev_all_rcu - Check if device is linked to an upper device
 6745 * @dev: device
 6746 * @upper_dev: upper device to check
 6747 *
 6748 * Find out if a device is linked to specified upper device and return true
 6749 * in case it is. Note that this checks the entire upper device chain.
 6750 * The caller must hold rcu lock.
 6751 */
 6752
 6753bool netdev_has_upper_dev_all_rcu(struct net_device *dev,
 6754				  struct net_device *upper_dev)
 6755{
 6756	struct netdev_nested_priv priv = {
 6757		.data = (void *)upper_dev,
 6758	};
 6759
 6760	return !!netdev_walk_all_upper_dev_rcu(dev, ____netdev_has_upper_dev,
 6761					       &priv);
 
 
 6762}
 6763EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu);
 6764
 6765/**
 6766 * netdev_has_any_upper_dev - Check if device is linked to some device
 6767 * @dev: device
 6768 *
 6769 * Find out if a device is linked to an upper device and return true in case
 6770 * it is. The caller must hold the RTNL lock.
 6771 */
 6772bool netdev_has_any_upper_dev(struct net_device *dev)
 6773{
 6774	ASSERT_RTNL();
 6775
 6776	return !list_empty(&dev->adj_list.upper);
 6777}
 6778EXPORT_SYMBOL(netdev_has_any_upper_dev);
 6779
 6780/**
 6781 * netdev_master_upper_dev_get - Get master upper device
 6782 * @dev: device
 
 6783 *
 6784 * Find a master upper device and return pointer to it or NULL in case
 6785 * it's not there. The caller must hold the RTNL lock.
 
 6786 */
 6787struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
 6788{
 6789	struct netdev_adjacent *upper;
 6790
 6791	ASSERT_RTNL();
 6792
 6793	if (list_empty(&dev->adj_list.upper))
 6794		return NULL;
 6795
 6796	upper = list_first_entry(&dev->adj_list.upper,
 6797				 struct netdev_adjacent, list);
 6798	if (likely(upper->master))
 6799		return upper->dev;
 6800	return NULL;
 6801}
 6802EXPORT_SYMBOL(netdev_master_upper_dev_get);
 6803
 6804static struct net_device *__netdev_master_upper_dev_get(struct net_device *dev)
 6805{
 6806	struct netdev_adjacent *upper;
 6807
 6808	ASSERT_RTNL();
 6809
 6810	if (list_empty(&dev->adj_list.upper))
 6811		return NULL;
 6812
 6813	upper = list_first_entry(&dev->adj_list.upper,
 6814				 struct netdev_adjacent, list);
 6815	if (likely(upper->master) && !upper->ignore)
 6816		return upper->dev;
 6817	return NULL;
 6818}
 6819
 6820/**
 6821 * netdev_has_any_lower_dev - Check if device is linked to some device
 6822 * @dev: device
 6823 *
 6824 * Find out if a device is linked to a lower device and return true in case
 6825 * it is. The caller must hold the RTNL lock.
 6826 */
 6827static bool netdev_has_any_lower_dev(struct net_device *dev)
 6828{
 6829	ASSERT_RTNL();
 6830
 6831	return !list_empty(&dev->adj_list.lower);
 6832}
 6833
 6834void *netdev_adjacent_get_private(struct list_head *adj_list)
 6835{
 6836	struct netdev_adjacent *adj;
 6837
 6838	adj = list_entry(adj_list, struct netdev_adjacent, list);
 6839
 6840	return adj->private;
 6841}
 6842EXPORT_SYMBOL(netdev_adjacent_get_private);
 6843
 6844/**
 6845 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list
 6846 * @dev: device
 6847 * @iter: list_head ** of the current position
 6848 *
 6849 * Gets the next device from the dev's upper list, starting from iter
 6850 * position. The caller must hold RCU read lock.
 6851 */
 6852struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
 6853						 struct list_head **iter)
 6854{
 6855	struct netdev_adjacent *upper;
 6856
 6857	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
 6858
 6859	upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
 6860
 6861	if (&upper->list == &dev->adj_list.upper)
 6862		return NULL;
 6863
 6864	*iter = &upper->list;
 6865
 6866	return upper->dev;
 6867}
 6868EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
 6869
 6870static struct net_device *__netdev_next_upper_dev(struct net_device *dev,
 6871						  struct list_head **iter,
 6872						  bool *ignore)
 6873{
 6874	struct netdev_adjacent *upper;
 6875
 6876	upper = list_entry((*iter)->next, struct netdev_adjacent, list);
 6877
 6878	if (&upper->list == &dev->adj_list.upper)
 6879		return NULL;
 6880
 6881	*iter = &upper->list;
 6882	*ignore = upper->ignore;
 6883
 6884	return upper->dev;
 6885}
 6886
 6887static struct net_device *netdev_next_upper_dev_rcu(struct net_device *dev,
 6888						    struct list_head **iter)
 6889{
 6890	struct netdev_adjacent *upper;
 6891
 6892	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
 6893
 6894	upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
 6895
 6896	if (&upper->list == &dev->adj_list.upper)
 6897		return NULL;
 6898
 6899	*iter = &upper->list;
 6900
 6901	return upper->dev;
 6902}
 6903
 6904static int __netdev_walk_all_upper_dev(struct net_device *dev,
 6905				       int (*fn)(struct net_device *dev,
 6906					 struct netdev_nested_priv *priv),
 6907				       struct netdev_nested_priv *priv)
 6908{
 6909	struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
 6910	struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
 6911	int ret, cur = 0;
 6912	bool ignore;
 6913
 6914	now = dev;
 6915	iter = &dev->adj_list.upper;
 6916
 6917	while (1) {
 6918		if (now != dev) {
 6919			ret = fn(now, priv);
 6920			if (ret)
 6921				return ret;
 6922		}
 6923
 6924		next = NULL;
 6925		while (1) {
 6926			udev = __netdev_next_upper_dev(now, &iter, &ignore);
 6927			if (!udev)
 6928				break;
 6929			if (ignore)
 6930				continue;
 6931
 6932			next = udev;
 6933			niter = &udev->adj_list.upper;
 6934			dev_stack[cur] = now;
 6935			iter_stack[cur++] = iter;
 6936			break;
 6937		}
 6938
 6939		if (!next) {
 6940			if (!cur)
 6941				return 0;
 6942			next = dev_stack[--cur];
 6943			niter = iter_stack[cur];
 6944		}
 6945
 6946		now = next;
 6947		iter = niter;
 
 
 
 6948	}
 6949
 6950	return 0;
 6951}
 6952
 6953int netdev_walk_all_upper_dev_rcu(struct net_device *dev,
 6954				  int (*fn)(struct net_device *dev,
 6955					    struct netdev_nested_priv *priv),
 6956				  struct netdev_nested_priv *priv)
 6957{
 6958	struct net_device *udev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
 6959	struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
 6960	int ret, cur = 0;
 6961
 6962	now = dev;
 6963	iter = &dev->adj_list.upper;
 6964
 6965	while (1) {
 6966		if (now != dev) {
 6967			ret = fn(now, priv);
 6968			if (ret)
 6969				return ret;
 6970		}
 6971
 6972		next = NULL;
 6973		while (1) {
 6974			udev = netdev_next_upper_dev_rcu(now, &iter);
 6975			if (!udev)
 6976				break;
 6977
 6978			next = udev;
 6979			niter = &udev->adj_list.upper;
 6980			dev_stack[cur] = now;
 6981			iter_stack[cur++] = iter;
 6982			break;
 6983		}
 6984
 6985		if (!next) {
 6986			if (!cur)
 6987				return 0;
 6988			next = dev_stack[--cur];
 6989			niter = iter_stack[cur];
 6990		}
 6991
 6992		now = next;
 6993		iter = niter;
 6994	}
 6995
 
 
 6996	return 0;
 6997}
 6998EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu);
 6999
 7000static bool __netdev_has_upper_dev(struct net_device *dev,
 7001				   struct net_device *upper_dev)
 7002{
 7003	struct netdev_nested_priv priv = {
 7004		.flags = 0,
 7005		.data = (void *)upper_dev,
 7006	};
 7007
 7008	ASSERT_RTNL();
 7009
 7010	return __netdev_walk_all_upper_dev(dev, ____netdev_has_upper_dev,
 7011					   &priv);
 7012}
 7013
 7014/**
 7015 * netdev_lower_get_next_private - Get the next ->private from the
 7016 *				   lower neighbour list
 7017 * @dev: device
 7018 * @iter: list_head ** of the current position
 7019 *
 7020 * Gets the next netdev_adjacent->private from the dev's lower neighbour
 7021 * list, starting from iter position. The caller must hold either hold the
 7022 * RTNL lock or its own locking that guarantees that the neighbour lower
 7023 * list will remain unchanged.
 7024 */
 7025void *netdev_lower_get_next_private(struct net_device *dev,
 7026				    struct list_head **iter)
 7027{
 7028	struct netdev_adjacent *lower;
 7029
 7030	lower = list_entry(*iter, struct netdev_adjacent, list);
 7031
 7032	if (&lower->list == &dev->adj_list.lower)
 7033		return NULL;
 7034
 7035	*iter = lower->list.next;
 7036
 7037	return lower->private;
 7038}
 7039EXPORT_SYMBOL(netdev_lower_get_next_private);
 7040
 7041/**
 7042 * netdev_lower_get_next_private_rcu - Get the next ->private from the
 7043 *				       lower neighbour list, RCU
 7044 *				       variant
 7045 * @dev: device
 7046 * @iter: list_head ** of the current position
 7047 *
 7048 * Gets the next netdev_adjacent->private from the dev's lower neighbour
 7049 * list, starting from iter position. The caller must hold RCU read lock.
 7050 */
 7051void *netdev_lower_get_next_private_rcu(struct net_device *dev,
 7052					struct list_head **iter)
 7053{
 7054	struct netdev_adjacent *lower;
 7055
 7056	WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
 7057
 7058	lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
 7059
 7060	if (&lower->list == &dev->adj_list.lower)
 7061		return NULL;
 7062
 7063	*iter = &lower->list;
 7064
 7065	return lower->private;
 7066}
 7067EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
 7068
 7069/**
 7070 * netdev_lower_get_next - Get the next device from the lower neighbour
 7071 *                         list
 7072 * @dev: device
 7073 * @iter: list_head ** of the current position
 7074 *
 7075 * Gets the next netdev_adjacent from the dev's lower neighbour
 7076 * list, starting from iter position. The caller must hold RTNL lock or
 7077 * its own locking that guarantees that the neighbour lower
 7078 * list will remain unchanged.
 7079 */
 7080void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
 7081{
 7082	struct netdev_adjacent *lower;
 7083
 7084	lower = list_entry(*iter, struct netdev_adjacent, list);
 7085
 7086	if (&lower->list == &dev->adj_list.lower)
 7087		return NULL;
 7088
 7089	*iter = lower->list.next;
 7090
 7091	return lower->dev;
 7092}
 7093EXPORT_SYMBOL(netdev_lower_get_next);
 7094
 7095static struct net_device *netdev_next_lower_dev(struct net_device *dev,
 7096						struct list_head **iter)
 7097{
 7098	struct netdev_adjacent *lower;
 7099
 7100	lower = list_entry((*iter)->next, struct netdev_adjacent, list);
 7101
 7102	if (&lower->list == &dev->adj_list.lower)
 7103		return NULL;
 7104
 7105	*iter = &lower->list;
 7106
 7107	return lower->dev;
 7108}
 7109
 7110static struct net_device *__netdev_next_lower_dev(struct net_device *dev,
 7111						  struct list_head **iter,
 7112						  bool *ignore)
 7113{
 7114	struct netdev_adjacent *lower;
 7115
 7116	lower = list_entry((*iter)->next, struct netdev_adjacent, list);
 7117
 7118	if (&lower->list == &dev->adj_list.lower)
 7119		return NULL;
 7120
 7121	*iter = &lower->list;
 7122	*ignore = lower->ignore;
 7123
 7124	return lower->dev;
 7125}
 7126
 7127int netdev_walk_all_lower_dev(struct net_device *dev,
 7128			      int (*fn)(struct net_device *dev,
 7129					struct netdev_nested_priv *priv),
 7130			      struct netdev_nested_priv *priv)
 7131{
 7132	struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
 7133	struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
 7134	int ret, cur = 0;
 7135
 7136	now = dev;
 7137	iter = &dev->adj_list.lower;
 
 7138
 7139	while (1) {
 7140		if (now != dev) {
 7141			ret = fn(now, priv);
 7142			if (ret)
 7143				return ret;
 7144		}
 7145
 7146		next = NULL;
 7147		while (1) {
 7148			ldev = netdev_next_lower_dev(now, &iter);
 7149			if (!ldev)
 7150				break;
 7151
 7152			next = ldev;
 7153			niter = &ldev->adj_list.lower;
 7154			dev_stack[cur] = now;
 7155			iter_stack[cur++] = iter;
 7156			break;
 7157		}
 7158
 7159		if (!next) {
 7160			if (!cur)
 7161				return 0;
 7162			next = dev_stack[--cur];
 7163			niter = iter_stack[cur];
 
 
 
 
 
 
 
 
 
 7164		}
 7165
 7166		now = next;
 7167		iter = niter;
 7168	}
 7169
 7170	return 0;
 7171}
 7172EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev);
 7173
 7174static int __netdev_walk_all_lower_dev(struct net_device *dev,
 7175				       int (*fn)(struct net_device *dev,
 7176					 struct netdev_nested_priv *priv),
 7177				       struct netdev_nested_priv *priv)
 7178{
 7179	struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
 7180	struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
 7181	int ret, cur = 0;
 7182	bool ignore;
 7183
 7184	now = dev;
 7185	iter = &dev->adj_list.lower;
 7186
 7187	while (1) {
 7188		if (now != dev) {
 7189			ret = fn(now, priv);
 7190			if (ret)
 7191				return ret;
 7192		}
 7193
 7194		next = NULL;
 7195		while (1) {
 7196			ldev = __netdev_next_lower_dev(now, &iter, &ignore);
 7197			if (!ldev)
 7198				break;
 7199			if (ignore)
 7200				continue;
 7201
 7202			next = ldev;
 7203			niter = &ldev->adj_list.lower;
 7204			dev_stack[cur] = now;
 7205			iter_stack[cur++] = iter;
 7206			break;
 7207		}
 7208
 7209		if (!next) {
 7210			if (!cur)
 7211				return 0;
 7212			next = dev_stack[--cur];
 7213			niter = iter_stack[cur];
 7214		}
 7215
 7216		now = next;
 7217		iter = niter;
 7218	}
 7219
 7220	return 0;
 
 
 
 7221}
 7222
 7223struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev,
 7224					     struct list_head **iter)
 
 
 
 
 
 7225{
 7226	struct netdev_adjacent *lower;
 
 
 7227
 7228	lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
 7229	if (&lower->list == &dev->adj_list.lower)
 7230		return NULL;
 7231
 7232	*iter = &lower->list;
 
 
 
 7233
 7234	return lower->dev;
 7235}
 7236EXPORT_SYMBOL(netdev_next_lower_dev_rcu);
 7237
 7238static u8 __netdev_upper_depth(struct net_device *dev)
 7239{
 7240	struct net_device *udev;
 7241	struct list_head *iter;
 7242	u8 max_depth = 0;
 7243	bool ignore;
 7244
 7245	for (iter = &dev->adj_list.upper,
 7246	     udev = __netdev_next_upper_dev(dev, &iter, &ignore);
 7247	     udev;
 7248	     udev = __netdev_next_upper_dev(dev, &iter, &ignore)) {
 7249		if (ignore)
 7250			continue;
 7251		if (max_depth < udev->upper_level)
 7252			max_depth = udev->upper_level;
 7253	}
 7254
 7255	return max_depth;
 
 7256}
 7257
 7258static u8 __netdev_lower_depth(struct net_device *dev)
 
 7259{
 7260	struct net_device *ldev;
 7261	struct list_head *iter;
 7262	u8 max_depth = 0;
 7263	bool ignore;
 7264
 7265	for (iter = &dev->adj_list.lower,
 7266	     ldev = __netdev_next_lower_dev(dev, &iter, &ignore);
 7267	     ldev;
 7268	     ldev = __netdev_next_lower_dev(dev, &iter, &ignore)) {
 7269		if (ignore)
 7270			continue;
 7271		if (max_depth < ldev->lower_level)
 7272			max_depth = ldev->lower_level;
 7273	}
 7274
 7275	return max_depth;
 7276}
 7277
 7278static int __netdev_update_upper_level(struct net_device *dev,
 7279				       struct netdev_nested_priv *__unused)
 7280{
 7281	dev->upper_level = __netdev_upper_depth(dev) + 1;
 7282	return 0;
 7283}
 7284
 7285#ifdef CONFIG_LOCKDEP
 7286static LIST_HEAD(net_unlink_list);
 7287
 7288static void net_unlink_todo(struct net_device *dev)
 7289{
 7290	if (list_empty(&dev->unlink_list))
 7291		list_add_tail(&dev->unlink_list, &net_unlink_list);
 
 
 
 
 
 
 
 
 
 
 
 
 
 7292}
 7293#endif
 7294
 7295static int __netdev_update_lower_level(struct net_device *dev,
 7296				       struct netdev_nested_priv *priv)
 
 
 
 7297{
 7298	dev->lower_level = __netdev_lower_depth(dev) + 1;
 7299
 7300#ifdef CONFIG_LOCKDEP
 7301	if (!priv)
 7302		return 0;
 7303
 7304	if (priv->flags & NESTED_SYNC_IMM)
 7305		dev->nested_level = dev->lower_level - 1;
 7306	if (priv->flags & NESTED_SYNC_TODO)
 7307		net_unlink_todo(dev);
 7308#endif
 7309	return 0;
 7310}
 7311
 7312int netdev_walk_all_lower_dev_rcu(struct net_device *dev,
 7313				  int (*fn)(struct net_device *dev,
 7314					    struct netdev_nested_priv *priv),
 7315				  struct netdev_nested_priv *priv)
 7316{
 7317	struct net_device *ldev, *next, *now, *dev_stack[MAX_NEST_DEV + 1];
 7318	struct list_head *niter, *iter, *iter_stack[MAX_NEST_DEV + 1];
 7319	int ret, cur = 0;
 7320
 7321	now = dev;
 7322	iter = &dev->adj_list.lower;
 7323
 7324	while (1) {
 7325		if (now != dev) {
 7326			ret = fn(now, priv);
 7327			if (ret)
 7328				return ret;
 7329		}
 7330
 7331		next = NULL;
 7332		while (1) {
 7333			ldev = netdev_next_lower_dev_rcu(now, &iter);
 7334			if (!ldev)
 7335				break;
 7336
 7337			next = ldev;
 7338			niter = &ldev->adj_list.lower;
 7339			dev_stack[cur] = now;
 7340			iter_stack[cur++] = iter;
 7341			break;
 7342		}
 7343
 7344		if (!next) {
 7345			if (!cur)
 7346				return 0;
 7347			next = dev_stack[--cur];
 7348			niter = iter_stack[cur];
 7349		}
 7350
 7351		now = next;
 7352		iter = niter;
 7353	}
 7354
 7355	return 0;
 7356}
 7357EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu);
 7358
 7359/**
 7360 * netdev_lower_get_first_private_rcu - Get the first ->private from the
 7361 *				       lower neighbour list, RCU
 7362 *				       variant
 7363 * @dev: device
 7364 *
 7365 * Gets the first netdev_adjacent->private from the dev's lower neighbour
 7366 * list. The caller must hold RCU read lock.
 7367 */
 7368void *netdev_lower_get_first_private_rcu(struct net_device *dev)
 7369{
 7370	struct netdev_adjacent *lower;
 7371
 7372	lower = list_first_or_null_rcu(&dev->adj_list.lower,
 7373			struct netdev_adjacent, list);
 7374	if (lower)
 7375		return lower->private;
 7376	return NULL;
 
 
 7377}
 7378EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
 7379
 7380/**
 7381 * netdev_master_upper_dev_get_rcu - Get master upper device
 7382 * @dev: device
 7383 *
 7384 * Find a master upper device and return pointer to it or NULL in case
 7385 * it's not there. The caller must hold the RCU read lock.
 7386 */
 7387struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
 7388{
 7389	struct netdev_adjacent *upper;
 7390
 7391	upper = list_first_or_null_rcu(&dev->adj_list.upper,
 7392				       struct netdev_adjacent, list);
 7393	if (upper && likely(upper->master))
 7394		return upper->dev;
 7395	return NULL;
 7396}
 7397EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
 7398
 7399static int netdev_adjacent_sysfs_add(struct net_device *dev,
 7400			      struct net_device *adj_dev,
 7401			      struct list_head *dev_list)
 7402{
 7403	char linkname[IFNAMSIZ+7];
 7404
 7405	sprintf(linkname, dev_list == &dev->adj_list.upper ?
 7406		"upper_%s" : "lower_%s", adj_dev->name);
 7407	return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
 7408				 linkname);
 7409}
 7410static void netdev_adjacent_sysfs_del(struct net_device *dev,
 7411			       char *name,
 7412			       struct list_head *dev_list)
 7413{
 7414	char linkname[IFNAMSIZ+7];
 7415
 7416	sprintf(linkname, dev_list == &dev->adj_list.upper ?
 7417		"upper_%s" : "lower_%s", name);
 7418	sysfs_remove_link(&(dev->dev.kobj), linkname);
 7419}
 7420
 7421static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev,
 7422						 struct net_device *adj_dev,
 7423						 struct list_head *dev_list)
 7424{
 7425	return (dev_list == &dev->adj_list.upper ||
 7426		dev_list == &dev->adj_list.lower) &&
 7427		net_eq(dev_net(dev), dev_net(adj_dev));
 7428}
 7429
 7430static int __netdev_adjacent_dev_insert(struct net_device *dev,
 7431					struct net_device *adj_dev,
 7432					struct list_head *dev_list,
 7433					void *private, bool master)
 7434{
 7435	struct netdev_adjacent *adj;
 7436	int ret;
 7437
 7438	adj = __netdev_find_adj(adj_dev, dev_list);
 7439
 7440	if (adj) {
 7441		adj->ref_nr += 1;
 7442		pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n",
 7443			 dev->name, adj_dev->name, adj->ref_nr);
 7444
 7445		return 0;
 7446	}
 7447
 7448	adj = kmalloc(sizeof(*adj), GFP_KERNEL);
 7449	if (!adj)
 7450		return -ENOMEM;
 7451
 7452	adj->dev = adj_dev;
 7453	adj->master = master;
 7454	adj->ref_nr = 1;
 7455	adj->private = private;
 7456	adj->ignore = false;
 7457	netdev_hold(adj_dev, &adj->dev_tracker, GFP_KERNEL);
 7458
 7459	pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n",
 7460		 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name);
 7461
 7462	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
 7463		ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
 7464		if (ret)
 7465			goto free_adj;
 7466	}
 7467
 7468	/* Ensure that master link is always the first item in list. */
 7469	if (master) {
 7470		ret = sysfs_create_link(&(dev->dev.kobj),
 7471					&(adj_dev->dev.kobj), "master");
 7472		if (ret)
 7473			goto remove_symlinks;
 7474
 7475		list_add_rcu(&adj->list, dev_list);
 7476	} else {
 7477		list_add_tail_rcu(&adj->list, dev_list);
 7478	}
 7479
 
 
 
 
 7480	return 0;
 7481
 7482remove_symlinks:
 7483	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
 7484		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
 7485free_adj:
 7486	netdev_put(adj_dev, &adj->dev_tracker);
 7487	kfree(adj);
 7488
 7489	return ret;
 7490}
 7491
 7492static void __netdev_adjacent_dev_remove(struct net_device *dev,
 7493					 struct net_device *adj_dev,
 7494					 u16 ref_nr,
 7495					 struct list_head *dev_list)
 7496{
 7497	struct netdev_adjacent *adj;
 7498
 7499	pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n",
 7500		 dev->name, adj_dev->name, ref_nr);
 7501
 7502	adj = __netdev_find_adj(adj_dev, dev_list);
 7503
 7504	if (!adj) {
 7505		pr_err("Adjacency does not exist for device %s from %s\n",
 7506		       dev->name, adj_dev->name);
 7507		WARN_ON(1);
 7508		return;
 7509	}
 7510
 7511	if (adj->ref_nr > ref_nr) {
 7512		pr_debug("adjacency: %s to %s ref_nr - %d = %d\n",
 7513			 dev->name, adj_dev->name, ref_nr,
 7514			 adj->ref_nr - ref_nr);
 7515		adj->ref_nr -= ref_nr;
 7516		return;
 7517	}
 7518
 7519	if (adj->master)
 7520		sysfs_remove_link(&(dev->dev.kobj), "master");
 7521
 7522	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
 7523		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
 7524
 7525	list_del_rcu(&adj->list);
 7526	pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n",
 7527		 adj_dev->name, dev->name, adj_dev->name);
 7528	netdev_put(adj_dev, &adj->dev_tracker);
 7529	kfree_rcu(adj, rcu);
 7530}
 7531
 7532static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
 7533					    struct net_device *upper_dev,
 7534					    struct list_head *up_list,
 7535					    struct list_head *down_list,
 7536					    void *private, bool master)
 7537{
 7538	int ret;
 7539
 7540	ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list,
 7541					   private, master);
 7542	if (ret)
 7543		return ret;
 7544
 7545	ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list,
 7546					   private, false);
 7547	if (ret) {
 7548		__netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list);
 7549		return ret;
 7550	}
 7551
 7552	return 0;
 7553}
 7554
 7555static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
 7556					       struct net_device *upper_dev,
 7557					       u16 ref_nr,
 7558					       struct list_head *up_list,
 7559					       struct list_head *down_list)
 7560{
 7561	__netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list);
 7562	__netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list);
 7563}
 7564
 7565static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
 7566						struct net_device *upper_dev,
 7567						void *private, bool master)
 7568{
 7569	return __netdev_adjacent_dev_link_lists(dev, upper_dev,
 7570						&dev->adj_list.upper,
 7571						&upper_dev->adj_list.lower,
 7572						private, master);
 7573}
 7574
 7575static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
 7576						   struct net_device *upper_dev)
 7577{
 7578	__netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1,
 7579					   &dev->adj_list.upper,
 7580					   &upper_dev->adj_list.lower);
 7581}
 7582
 7583static int __netdev_upper_dev_link(struct net_device *dev,
 7584				   struct net_device *upper_dev, bool master,
 7585				   void *upper_priv, void *upper_info,
 7586				   struct netdev_nested_priv *priv,
 7587				   struct netlink_ext_ack *extack)
 7588{
 7589	struct netdev_notifier_changeupper_info changeupper_info = {
 7590		.info = {
 7591			.dev = dev,
 7592			.extack = extack,
 7593		},
 7594		.upper_dev = upper_dev,
 7595		.master = master,
 7596		.linking = true,
 7597		.upper_info = upper_info,
 7598	};
 7599	struct net_device *master_dev;
 7600	int ret = 0;
 7601
 7602	ASSERT_RTNL();
 7603
 7604	if (dev == upper_dev)
 7605		return -EBUSY;
 7606
 7607	/* To prevent loops, check if dev is not upper device to upper_dev. */
 7608	if (__netdev_has_upper_dev(upper_dev, dev))
 7609		return -EBUSY;
 7610
 7611	if ((dev->lower_level + upper_dev->upper_level) > MAX_NEST_DEV)
 7612		return -EMLINK;
 7613
 7614	if (!master) {
 7615		if (__netdev_has_upper_dev(dev, upper_dev))
 7616			return -EEXIST;
 7617	} else {
 7618		master_dev = __netdev_master_upper_dev_get(dev);
 7619		if (master_dev)
 7620			return master_dev == upper_dev ? -EEXIST : -EBUSY;
 7621	}
 7622
 7623	ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER,
 7624					    &changeupper_info.info);
 7625	ret = notifier_to_errno(ret);
 7626	if (ret)
 7627		return ret;
 7628
 7629	ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv,
 7630						   master);
 7631	if (ret)
 7632		return ret;
 7633
 7634	ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER,
 7635					    &changeupper_info.info);
 7636	ret = notifier_to_errno(ret);
 7637	if (ret)
 7638		goto rollback;
 7639
 7640	__netdev_update_upper_level(dev, NULL);
 7641	__netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL);
 7642
 7643	__netdev_update_lower_level(upper_dev, priv);
 7644	__netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level,
 7645				    priv);
 7646
 7647	return 0;
 7648
 7649rollback:
 7650	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
 7651
 7652	return ret;
 7653}
 7654
 7655/**
 7656 * netdev_upper_dev_link - Add a link to the upper device
 7657 * @dev: device
 7658 * @upper_dev: new upper device
 7659 * @extack: netlink extended ack
 7660 *
 7661 * Adds a link to device which is upper to this one. The caller must hold
 7662 * the RTNL lock. On a failure a negative errno code is returned.
 7663 * On success the reference counts are adjusted and the function
 7664 * returns zero.
 7665 */
 7666int netdev_upper_dev_link(struct net_device *dev,
 7667			  struct net_device *upper_dev,
 7668			  struct netlink_ext_ack *extack)
 7669{
 7670	struct netdev_nested_priv priv = {
 7671		.flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO,
 7672		.data = NULL,
 7673	};
 7674
 7675	return __netdev_upper_dev_link(dev, upper_dev, false,
 7676				       NULL, NULL, &priv, extack);
 7677}
 7678EXPORT_SYMBOL(netdev_upper_dev_link);
 7679
 7680/**
 7681 * netdev_master_upper_dev_link - Add a master link to the upper device
 7682 * @dev: device
 7683 * @upper_dev: new upper device
 7684 * @upper_priv: upper device private
 7685 * @upper_info: upper info to be passed down via notifier
 7686 * @extack: netlink extended ack
 7687 *
 7688 * Adds a link to device which is upper to this one. In this case, only
 7689 * one master upper device can be linked, although other non-master devices
 7690 * might be linked as well. The caller must hold the RTNL lock.
 7691 * On a failure a negative errno code is returned. On success the reference
 7692 * counts are adjusted and the function returns zero.
 7693 */
 7694int netdev_master_upper_dev_link(struct net_device *dev,
 7695				 struct net_device *upper_dev,
 7696				 void *upper_priv, void *upper_info,
 7697				 struct netlink_ext_ack *extack)
 7698{
 7699	struct netdev_nested_priv priv = {
 7700		.flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO,
 7701		.data = NULL,
 7702	};
 7703
 7704	return __netdev_upper_dev_link(dev, upper_dev, true,
 7705				       upper_priv, upper_info, &priv, extack);
 7706}
 7707EXPORT_SYMBOL(netdev_master_upper_dev_link);
 7708
 7709static void __netdev_upper_dev_unlink(struct net_device *dev,
 7710				      struct net_device *upper_dev,
 7711				      struct netdev_nested_priv *priv)
 7712{
 7713	struct netdev_notifier_changeupper_info changeupper_info = {
 7714		.info = {
 7715			.dev = dev,
 7716		},
 7717		.upper_dev = upper_dev,
 7718		.linking = false,
 7719	};
 7720
 7721	ASSERT_RTNL();
 7722
 7723	changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev;
 7724
 7725	call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER,
 7726				      &changeupper_info.info);
 7727
 7728	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
 7729
 7730	call_netdevice_notifiers_info(NETDEV_CHANGEUPPER,
 7731				      &changeupper_info.info);
 7732
 7733	__netdev_update_upper_level(dev, NULL);
 7734	__netdev_walk_all_lower_dev(dev, __netdev_update_upper_level, NULL);
 7735
 7736	__netdev_update_lower_level(upper_dev, priv);
 7737	__netdev_walk_all_upper_dev(upper_dev, __netdev_update_lower_level,
 7738				    priv);
 7739}
 7740
 7741/**
 7742 * netdev_upper_dev_unlink - Removes a link to upper device
 7743 * @dev: device
 7744 * @upper_dev: new upper device
 7745 *
 7746 * Removes a link to device which is upper to this one. The caller must hold
 7747 * the RTNL lock.
 7748 */
 7749void netdev_upper_dev_unlink(struct net_device *dev,
 7750			     struct net_device *upper_dev)
 7751{
 7752	struct netdev_nested_priv priv = {
 7753		.flags = NESTED_SYNC_TODO,
 7754		.data = NULL,
 7755	};
 7756
 7757	__netdev_upper_dev_unlink(dev, upper_dev, &priv);
 7758}
 7759EXPORT_SYMBOL(netdev_upper_dev_unlink);
 7760
 7761static void __netdev_adjacent_dev_set(struct net_device *upper_dev,
 7762				      struct net_device *lower_dev,
 7763				      bool val)
 7764{
 7765	struct netdev_adjacent *adj;
 7766
 7767	adj = __netdev_find_adj(lower_dev, &upper_dev->adj_list.lower);
 7768	if (adj)
 7769		adj->ignore = val;
 7770
 7771	adj = __netdev_find_adj(upper_dev, &lower_dev->adj_list.upper);
 7772	if (adj)
 7773		adj->ignore = val;
 7774}
 
 
 7775
 7776static void netdev_adjacent_dev_disable(struct net_device *upper_dev,
 7777					struct net_device *lower_dev)
 7778{
 7779	__netdev_adjacent_dev_set(upper_dev, lower_dev, true);
 7780}
 7781
 7782static void netdev_adjacent_dev_enable(struct net_device *upper_dev,
 7783				       struct net_device *lower_dev)
 7784{
 7785	__netdev_adjacent_dev_set(upper_dev, lower_dev, false);
 7786}
 
 
 7787
 7788int netdev_adjacent_change_prepare(struct net_device *old_dev,
 7789				   struct net_device *new_dev,
 7790				   struct net_device *dev,
 7791				   struct netlink_ext_ack *extack)
 7792{
 7793	struct netdev_nested_priv priv = {
 7794		.flags = 0,
 7795		.data = NULL,
 7796	};
 7797	int err;
 7798
 7799	if (!new_dev)
 7800		return 0;
 7801
 7802	if (old_dev && new_dev != old_dev)
 7803		netdev_adjacent_dev_disable(dev, old_dev);
 7804	err = __netdev_upper_dev_link(new_dev, dev, false, NULL, NULL, &priv,
 7805				      extack);
 7806	if (err) {
 7807		if (old_dev && new_dev != old_dev)
 7808			netdev_adjacent_dev_enable(dev, old_dev);
 7809		return err;
 7810	}
 7811
 7812	return 0;
 7813}
 7814EXPORT_SYMBOL(netdev_adjacent_change_prepare);
 7815
 7816void netdev_adjacent_change_commit(struct net_device *old_dev,
 7817				   struct net_device *new_dev,
 7818				   struct net_device *dev)
 7819{
 7820	struct netdev_nested_priv priv = {
 7821		.flags = NESTED_SYNC_IMM | NESTED_SYNC_TODO,
 7822		.data = NULL,
 7823	};
 7824
 7825	if (!new_dev || !old_dev)
 7826		return;
 7827
 7828	if (new_dev == old_dev)
 7829		return;
 7830
 7831	netdev_adjacent_dev_enable(dev, old_dev);
 7832	__netdev_upper_dev_unlink(old_dev, dev, &priv);
 7833}
 7834EXPORT_SYMBOL(netdev_adjacent_change_commit);
 7835
 7836void netdev_adjacent_change_abort(struct net_device *old_dev,
 7837				  struct net_device *new_dev,
 7838				  struct net_device *dev)
 7839{
 7840	struct netdev_nested_priv priv = {
 7841		.flags = 0,
 7842		.data = NULL,
 7843	};
 7844
 7845	if (!new_dev)
 7846		return;
 7847
 7848	if (old_dev && new_dev != old_dev)
 7849		netdev_adjacent_dev_enable(dev, old_dev);
 7850
 7851	__netdev_upper_dev_unlink(new_dev, dev, &priv);
 7852}
 7853EXPORT_SYMBOL(netdev_adjacent_change_abort);
 7854
 7855/**
 7856 * netdev_bonding_info_change - Dispatch event about slave change
 7857 * @dev: device
 7858 * @bonding_info: info to dispatch
 7859 *
 7860 * Send NETDEV_BONDING_INFO to netdev notifiers with info.
 7861 * The caller must hold the RTNL lock.
 7862 */
 7863void netdev_bonding_info_change(struct net_device *dev,
 7864				struct netdev_bonding_info *bonding_info)
 7865{
 7866	struct netdev_notifier_bonding_info info = {
 7867		.info.dev = dev,
 7868	};
 7869
 7870	memcpy(&info.bonding_info, bonding_info,
 7871	       sizeof(struct netdev_bonding_info));
 7872	call_netdevice_notifiers_info(NETDEV_BONDING_INFO,
 7873				      &info.info);
 7874}
 7875EXPORT_SYMBOL(netdev_bonding_info_change);
 7876
 7877static int netdev_offload_xstats_enable_l3(struct net_device *dev,
 7878					   struct netlink_ext_ack *extack)
 7879{
 7880	struct netdev_notifier_offload_xstats_info info = {
 7881		.info.dev = dev,
 7882		.info.extack = extack,
 7883		.type = NETDEV_OFFLOAD_XSTATS_TYPE_L3,
 7884	};
 7885	int err;
 7886	int rc;
 7887
 7888	dev->offload_xstats_l3 = kzalloc(sizeof(*dev->offload_xstats_l3),
 7889					 GFP_KERNEL);
 7890	if (!dev->offload_xstats_l3)
 7891		return -ENOMEM;
 7892
 7893	rc = call_netdevice_notifiers_info_robust(NETDEV_OFFLOAD_XSTATS_ENABLE,
 7894						  NETDEV_OFFLOAD_XSTATS_DISABLE,
 7895						  &info.info);
 7896	err = notifier_to_errno(rc);
 7897	if (err)
 7898		goto free_stats;
 7899
 7900	return 0;
 7901
 7902free_stats:
 7903	kfree(dev->offload_xstats_l3);
 7904	dev->offload_xstats_l3 = NULL;
 7905	return err;
 7906}
 7907
 7908int netdev_offload_xstats_enable(struct net_device *dev,
 7909				 enum netdev_offload_xstats_type type,
 7910				 struct netlink_ext_ack *extack)
 7911{
 7912	ASSERT_RTNL();
 7913
 7914	if (netdev_offload_xstats_enabled(dev, type))
 7915		return -EALREADY;
 
 
 
 
 
 
 
 
 
 
 
 
 
 7916
 7917	switch (type) {
 7918	case NETDEV_OFFLOAD_XSTATS_TYPE_L3:
 7919		return netdev_offload_xstats_enable_l3(dev, extack);
 
 7920	}
 7921
 7922	WARN_ON(1);
 7923	return -EINVAL;
 7924}
 7925EXPORT_SYMBOL(netdev_offload_xstats_enable);
 7926
 7927static void netdev_offload_xstats_disable_l3(struct net_device *dev)
 
 7928{
 7929	struct netdev_notifier_offload_xstats_info info = {
 7930		.info.dev = dev,
 7931		.type = NETDEV_OFFLOAD_XSTATS_TYPE_L3,
 7932	};
 7933
 7934	call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_DISABLE,
 7935				      &info.info);
 7936	kfree(dev->offload_xstats_l3);
 7937	dev->offload_xstats_l3 = NULL;
 7938}
 7939
 7940int netdev_offload_xstats_disable(struct net_device *dev,
 7941				  enum netdev_offload_xstats_type type)
 7942{
 7943	ASSERT_RTNL();
 7944
 7945	if (!netdev_offload_xstats_enabled(dev, type))
 7946		return -EALREADY;
 
 
 
 
 
 7947
 7948	switch (type) {
 7949	case NETDEV_OFFLOAD_XSTATS_TYPE_L3:
 7950		netdev_offload_xstats_disable_l3(dev);
 7951		return 0;
 7952	}
 7953
 7954	WARN_ON(1);
 7955	return -EINVAL;
 7956}
 7957EXPORT_SYMBOL(netdev_offload_xstats_disable);
 7958
 7959static void netdev_offload_xstats_disable_all(struct net_device *dev)
 7960{
 7961	netdev_offload_xstats_disable(dev, NETDEV_OFFLOAD_XSTATS_TYPE_L3);
 7962}
 7963
 7964static struct rtnl_hw_stats64 *
 7965netdev_offload_xstats_get_ptr(const struct net_device *dev,
 7966			      enum netdev_offload_xstats_type type)
 7967{
 7968	switch (type) {
 7969	case NETDEV_OFFLOAD_XSTATS_TYPE_L3:
 7970		return dev->offload_xstats_l3;
 7971	}
 7972
 7973	WARN_ON(1);
 7974	return NULL;
 7975}
 7976
 7977bool netdev_offload_xstats_enabled(const struct net_device *dev,
 7978				   enum netdev_offload_xstats_type type)
 7979{
 7980	ASSERT_RTNL();
 7981
 7982	return netdev_offload_xstats_get_ptr(dev, type);
 7983}
 7984EXPORT_SYMBOL(netdev_offload_xstats_enabled);
 7985
 7986struct netdev_notifier_offload_xstats_ru {
 7987	bool used;
 7988};
 7989
 7990struct netdev_notifier_offload_xstats_rd {
 7991	struct rtnl_hw_stats64 stats;
 7992	bool used;
 
 
 
 7993};
 7994
 7995static void netdev_hw_stats64_add(struct rtnl_hw_stats64 *dest,
 7996				  const struct rtnl_hw_stats64 *src)
 7997{
 7998	dest->rx_packets	  += src->rx_packets;
 7999	dest->tx_packets	  += src->tx_packets;
 8000	dest->rx_bytes		  += src->rx_bytes;
 8001	dest->tx_bytes		  += src->tx_bytes;
 8002	dest->rx_errors		  += src->rx_errors;
 8003	dest->tx_errors		  += src->tx_errors;
 8004	dest->rx_dropped	  += src->rx_dropped;
 8005	dest->tx_dropped	  += src->tx_dropped;
 8006	dest->multicast		  += src->multicast;
 8007}
 8008
 8009static int netdev_offload_xstats_get_used(struct net_device *dev,
 8010					  enum netdev_offload_xstats_type type,
 8011					  bool *p_used,
 8012					  struct netlink_ext_ack *extack)
 8013{
 8014	struct netdev_notifier_offload_xstats_ru report_used = {};
 8015	struct netdev_notifier_offload_xstats_info info = {
 8016		.info.dev = dev,
 8017		.info.extack = extack,
 8018		.type = type,
 8019		.report_used = &report_used,
 8020	};
 8021	int rc;
 8022
 8023	WARN_ON(!netdev_offload_xstats_enabled(dev, type));
 8024	rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_USED,
 8025					   &info.info);
 8026	*p_used = report_used.used;
 8027	return notifier_to_errno(rc);
 8028}
 8029
 8030static int netdev_offload_xstats_get_stats(struct net_device *dev,
 8031					   enum netdev_offload_xstats_type type,
 8032					   struct rtnl_hw_stats64 *p_stats,
 8033					   bool *p_used,
 8034					   struct netlink_ext_ack *extack)
 8035{
 8036	struct netdev_notifier_offload_xstats_rd report_delta = {};
 8037	struct netdev_notifier_offload_xstats_info info = {
 8038		.info.dev = dev,
 8039		.info.extack = extack,
 8040		.type = type,
 8041		.report_delta = &report_delta,
 8042	};
 8043	struct rtnl_hw_stats64 *stats;
 8044	int rc;
 8045
 8046	stats = netdev_offload_xstats_get_ptr(dev, type);
 8047	if (WARN_ON(!stats))
 8048		return -EINVAL;
 8049
 8050	rc = call_netdevice_notifiers_info(NETDEV_OFFLOAD_XSTATS_REPORT_DELTA,
 8051					   &info.info);
 8052
 8053	/* Cache whatever we got, even if there was an error, otherwise the
 8054	 * successful stats retrievals would get lost.
 8055	 */
 8056	netdev_hw_stats64_add(stats, &report_delta.stats);
 8057
 8058	if (p_stats)
 8059		*p_stats = *stats;
 8060	*p_used = report_delta.used;
 8061
 8062	return notifier_to_errno(rc);
 8063}
 8064
 8065int netdev_offload_xstats_get(struct net_device *dev,
 8066			      enum netdev_offload_xstats_type type,
 8067			      struct rtnl_hw_stats64 *p_stats, bool *p_used,
 8068			      struct netlink_ext_ack *extack)
 8069{
 8070	ASSERT_RTNL();
 8071
 8072	if (p_stats)
 8073		return netdev_offload_xstats_get_stats(dev, type, p_stats,
 8074						       p_used, extack);
 8075	else
 8076		return netdev_offload_xstats_get_used(dev, type, p_used,
 8077						      extack);
 8078}
 8079EXPORT_SYMBOL(netdev_offload_xstats_get);
 8080
 8081void
 8082netdev_offload_xstats_report_delta(struct netdev_notifier_offload_xstats_rd *report_delta,
 8083				   const struct rtnl_hw_stats64 *stats)
 8084{
 8085	report_delta->used = true;
 8086	netdev_hw_stats64_add(&report_delta->stats, stats);
 8087}
 8088EXPORT_SYMBOL(netdev_offload_xstats_report_delta);
 8089
 8090void
 8091netdev_offload_xstats_report_used(struct netdev_notifier_offload_xstats_ru *report_used)
 8092{
 8093	report_used->used = true;
 
 
 
 
 
 
 
 
 8094}
 8095EXPORT_SYMBOL(netdev_offload_xstats_report_used);
 8096
 8097void netdev_offload_xstats_push_delta(struct net_device *dev,
 8098				      enum netdev_offload_xstats_type type,
 8099				      const struct rtnl_hw_stats64 *p_stats)
 8100{
 8101	struct rtnl_hw_stats64 *stats;
 8102
 8103	ASSERT_RTNL();
 8104
 8105	stats = netdev_offload_xstats_get_ptr(dev, type);
 8106	if (WARN_ON(!stats))
 8107		return;
 8108
 8109	netdev_hw_stats64_add(stats, p_stats);
 8110}
 8111EXPORT_SYMBOL(netdev_offload_xstats_push_delta);
 8112
 8113/**
 8114 * netdev_get_xmit_slave - Get the xmit slave of master device
 8115 * @dev: device
 8116 * @skb: The packet
 8117 * @all_slaves: assume all the slaves are active
 8118 *
 8119 * The reference counters are not incremented so the caller must be
 8120 * careful with locks. The caller must hold RCU lock.
 8121 * %NULL is returned if no slave is found.
 8122 */
 8123
 8124struct net_device *netdev_get_xmit_slave(struct net_device *dev,
 8125					 struct sk_buff *skb,
 8126					 bool all_slaves)
 8127{
 8128	const struct net_device_ops *ops = dev->netdev_ops;
 8129
 8130	if (!ops->ndo_get_xmit_slave)
 8131		return NULL;
 8132	return ops->ndo_get_xmit_slave(dev, skb, all_slaves);
 8133}
 8134EXPORT_SYMBOL(netdev_get_xmit_slave);
 8135
 8136static struct net_device *netdev_sk_get_lower_dev(struct net_device *dev,
 8137						  struct sock *sk)
 8138{
 8139	const struct net_device_ops *ops = dev->netdev_ops;
 8140
 8141	if (!ops->ndo_sk_get_lower_dev)
 8142		return NULL;
 8143	return ops->ndo_sk_get_lower_dev(dev, sk);
 8144}
 8145
 8146/**
 8147 * netdev_sk_get_lowest_dev - Get the lowest device in chain given device and socket
 8148 * @dev: device
 8149 * @sk: the socket
 8150 *
 8151 * %NULL is returned if no lower device is found.
 
 
 
 8152 */
 8153
 8154struct net_device *netdev_sk_get_lowest_dev(struct net_device *dev,
 8155					    struct sock *sk)
 8156{
 8157	struct net_device *lower;
 8158
 8159	lower = netdev_sk_get_lower_dev(dev, sk);
 8160	while (lower) {
 8161		dev = lower;
 8162		lower = netdev_sk_get_lower_dev(dev, sk);
 8163	}
 8164
 8165	return dev;
 8166}
 8167EXPORT_SYMBOL(netdev_sk_get_lowest_dev);
 8168
 8169static void netdev_adjacent_add_links(struct net_device *dev)
 8170{
 8171	struct netdev_adjacent *iter;
 8172
 8173	struct net *net = dev_net(dev);
 8174
 8175	list_for_each_entry(iter, &dev->adj_list.upper, list) {
 8176		if (!net_eq(net, dev_net(iter->dev)))
 8177			continue;
 8178		netdev_adjacent_sysfs_add(iter->dev, dev,
 8179					  &iter->dev->adj_list.lower);
 8180		netdev_adjacent_sysfs_add(dev, iter->dev,
 8181					  &dev->adj_list.upper);
 8182	}
 8183
 8184	list_for_each_entry(iter, &dev->adj_list.lower, list) {
 8185		if (!net_eq(net, dev_net(iter->dev)))
 8186			continue;
 8187		netdev_adjacent_sysfs_add(iter->dev, dev,
 8188					  &iter->dev->adj_list.upper);
 8189		netdev_adjacent_sysfs_add(dev, iter->dev,
 8190					  &dev->adj_list.lower);
 8191	}
 8192}
 8193
 8194static void netdev_adjacent_del_links(struct net_device *dev)
 8195{
 8196	struct netdev_adjacent *iter;
 8197
 8198	struct net *net = dev_net(dev);
 8199
 8200	list_for_each_entry(iter, &dev->adj_list.upper, list) {
 8201		if (!net_eq(net, dev_net(iter->dev)))
 8202			continue;
 8203		netdev_adjacent_sysfs_del(iter->dev, dev->name,
 8204					  &iter->dev->adj_list.lower);
 8205		netdev_adjacent_sysfs_del(dev, iter->dev->name,
 8206					  &dev->adj_list.upper);
 8207	}
 8208
 8209	list_for_each_entry(iter, &dev->adj_list.lower, list) {
 8210		if (!net_eq(net, dev_net(iter->dev)))
 8211			continue;
 8212		netdev_adjacent_sysfs_del(iter->dev, dev->name,
 8213					  &iter->dev->adj_list.upper);
 8214		netdev_adjacent_sysfs_del(dev, iter->dev->name,
 8215					  &dev->adj_list.lower);
 8216	}
 8217}
 8218
 8219void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
 8220{
 8221	struct netdev_adjacent *iter;
 8222
 8223	struct net *net = dev_net(dev);
 8224
 8225	list_for_each_entry(iter, &dev->adj_list.upper, list) {
 8226		if (!net_eq(net, dev_net(iter->dev)))
 8227			continue;
 8228		netdev_adjacent_sysfs_del(iter->dev, oldname,
 8229					  &iter->dev->adj_list.lower);
 8230		netdev_adjacent_sysfs_add(iter->dev, dev,
 8231					  &iter->dev->adj_list.lower);
 8232	}
 8233
 8234	list_for_each_entry(iter, &dev->adj_list.lower, list) {
 8235		if (!net_eq(net, dev_net(iter->dev)))
 8236			continue;
 8237		netdev_adjacent_sysfs_del(iter->dev, oldname,
 8238					  &iter->dev->adj_list.upper);
 8239		netdev_adjacent_sysfs_add(iter->dev, dev,
 8240					  &iter->dev->adj_list.upper);
 8241	}
 8242}
 8243
 8244void *netdev_lower_dev_get_private(struct net_device *dev,
 8245				   struct net_device *lower_dev)
 8246{
 8247	struct netdev_adjacent *lower;
 8248
 8249	if (!lower_dev)
 8250		return NULL;
 8251	lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower);
 8252	if (!lower)
 8253		return NULL;
 8254
 8255	return lower->private;
 
 
 8256}
 8257EXPORT_SYMBOL(netdev_lower_dev_get_private);
 8258
 8259
 8260/**
 8261 * netdev_lower_state_changed - Dispatch event about lower device state change
 8262 * @lower_dev: device
 8263 * @lower_state_info: state to dispatch
 8264 *
 8265 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info.
 8266 * The caller must hold the RTNL lock.
 
 
 8267 */
 8268void netdev_lower_state_changed(struct net_device *lower_dev,
 8269				void *lower_state_info)
 8270{
 8271	struct netdev_notifier_changelowerstate_info changelowerstate_info = {
 8272		.info.dev = lower_dev,
 8273	};
 8274
 8275	ASSERT_RTNL();
 8276	changelowerstate_info.lower_state_info = lower_state_info;
 8277	call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE,
 8278				      &changelowerstate_info.info);
 
 
 
 
 
 
 
 
 8279}
 8280EXPORT_SYMBOL(netdev_lower_state_changed);
 8281
 8282static void dev_change_rx_flags(struct net_device *dev, int flags)
 8283{
 8284	const struct net_device_ops *ops = dev->netdev_ops;
 8285
 8286	if (ops->ndo_change_rx_flags)
 8287		ops->ndo_change_rx_flags(dev, flags);
 8288}
 8289
 8290static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
 8291{
 8292	unsigned int old_flags = dev->flags;
 8293	kuid_t uid;
 8294	kgid_t gid;
 8295
 8296	ASSERT_RTNL();
 8297
 8298	dev->flags |= IFF_PROMISC;
 8299	dev->promiscuity += inc;
 8300	if (dev->promiscuity == 0) {
 8301		/*
 8302		 * Avoid overflow.
 8303		 * If inc causes overflow, untouch promisc and return error.
 8304		 */
 8305		if (inc < 0)
 8306			dev->flags &= ~IFF_PROMISC;
 8307		else {
 8308			dev->promiscuity -= inc;
 8309			netdev_warn(dev, "promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n");
 
 
 8310			return -EOVERFLOW;
 8311		}
 8312	}
 8313	if (dev->flags != old_flags) {
 8314		pr_info("device %s %s promiscuous mode\n",
 8315			dev->name,
 8316			dev->flags & IFF_PROMISC ? "entered" : "left");
 8317		if (audit_enabled) {
 8318			current_uid_gid(&uid, &gid);
 8319			audit_log(audit_context(), GFP_ATOMIC,
 8320				  AUDIT_ANOM_PROMISCUOUS,
 8321				  "dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
 8322				  dev->name, (dev->flags & IFF_PROMISC),
 8323				  (old_flags & IFF_PROMISC),
 8324				  from_kuid(&init_user_ns, audit_get_loginuid(current)),
 8325				  from_kuid(&init_user_ns, uid),
 8326				  from_kgid(&init_user_ns, gid),
 8327				  audit_get_sessionid(current));
 8328		}
 8329
 8330		dev_change_rx_flags(dev, IFF_PROMISC);
 8331	}
 8332	if (notify)
 8333		__dev_notify_flags(dev, old_flags, IFF_PROMISC, 0, NULL);
 8334	return 0;
 8335}
 8336
 8337/**
 8338 *	dev_set_promiscuity	- update promiscuity count on a device
 8339 *	@dev: device
 8340 *	@inc: modifier
 8341 *
 8342 *	Add or remove promiscuity from a device. While the count in the device
 8343 *	remains above zero the interface remains promiscuous. Once it hits zero
 8344 *	the device reverts back to normal filtering operation. A negative inc
 8345 *	value is used to drop promiscuity on the device.
 8346 *	Return 0 if successful or a negative errno code on error.
 8347 */
 8348int dev_set_promiscuity(struct net_device *dev, int inc)
 8349{
 8350	unsigned int old_flags = dev->flags;
 8351	int err;
 8352
 8353	err = __dev_set_promiscuity(dev, inc, true);
 8354	if (err < 0)
 8355		return err;
 8356	if (dev->flags != old_flags)
 8357		dev_set_rx_mode(dev);
 8358	return err;
 8359}
 8360EXPORT_SYMBOL(dev_set_promiscuity);
 8361
 8362static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
 
 
 
 
 
 
 
 
 
 
 
 
 
 8363{
 8364	unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
 8365
 8366	ASSERT_RTNL();
 8367
 8368	dev->flags |= IFF_ALLMULTI;
 8369	dev->allmulti += inc;
 8370	if (dev->allmulti == 0) {
 8371		/*
 8372		 * Avoid overflow.
 8373		 * If inc causes overflow, untouch allmulti and return error.
 8374		 */
 8375		if (inc < 0)
 8376			dev->flags &= ~IFF_ALLMULTI;
 8377		else {
 8378			dev->allmulti -= inc;
 8379			netdev_warn(dev, "allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n");
 
 
 8380			return -EOVERFLOW;
 8381		}
 8382	}
 8383	if (dev->flags ^ old_flags) {
 8384		dev_change_rx_flags(dev, IFF_ALLMULTI);
 8385		dev_set_rx_mode(dev);
 8386		if (notify)
 8387			__dev_notify_flags(dev, old_flags,
 8388					   dev->gflags ^ old_gflags, 0, NULL);
 8389	}
 8390	return 0;
 8391}
 8392
 8393/**
 8394 *	dev_set_allmulti	- update allmulti count on a device
 8395 *	@dev: device
 8396 *	@inc: modifier
 8397 *
 8398 *	Add or remove reception of all multicast frames to a device. While the
 8399 *	count in the device remains above zero the interface remains listening
 8400 *	to all interfaces. Once it hits zero the device reverts back to normal
 8401 *	filtering operation. A negative @inc value is used to drop the counter
 8402 *	when releasing a resource needing all multicasts.
 8403 *	Return 0 if successful or a negative errno code on error.
 8404 */
 8405
 8406int dev_set_allmulti(struct net_device *dev, int inc)
 8407{
 8408	return __dev_set_allmulti(dev, inc, true);
 8409}
 8410EXPORT_SYMBOL(dev_set_allmulti);
 8411
 8412/*
 8413 *	Upload unicast and multicast address lists to device and
 8414 *	configure RX filtering. When the device doesn't support unicast
 8415 *	filtering it is put in promiscuous mode while unicast addresses
 8416 *	are present.
 8417 */
 8418void __dev_set_rx_mode(struct net_device *dev)
 8419{
 8420	const struct net_device_ops *ops = dev->netdev_ops;
 8421
 8422	/* dev_open will call this function so the list will stay sane. */
 8423	if (!(dev->flags&IFF_UP))
 8424		return;
 8425
 8426	if (!netif_device_present(dev))
 8427		return;
 8428
 8429	if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
 
 
 8430		/* Unicast addresses changes may only happen under the rtnl,
 8431		 * therefore calling __dev_set_promiscuity here is safe.
 8432		 */
 8433		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
 8434			__dev_set_promiscuity(dev, 1, false);
 8435			dev->uc_promisc = true;
 8436		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {
 8437			__dev_set_promiscuity(dev, -1, false);
 8438			dev->uc_promisc = false;
 8439		}
 8440	}
 8441
 8442	if (ops->ndo_set_rx_mode)
 8443		ops->ndo_set_rx_mode(dev);
 
 8444}
 8445
 8446void dev_set_rx_mode(struct net_device *dev)
 8447{
 8448	netif_addr_lock_bh(dev);
 8449	__dev_set_rx_mode(dev);
 8450	netif_addr_unlock_bh(dev);
 8451}
 8452
 8453/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 8454 *	dev_get_flags - get flags reported to userspace
 8455 *	@dev: device
 8456 *
 8457 *	Get the combination of flag bits exported through APIs to userspace.
 8458 */
 8459unsigned int dev_get_flags(const struct net_device *dev)
 8460{
 8461	unsigned int flags;
 8462
 8463	flags = (dev->flags & ~(IFF_PROMISC |
 8464				IFF_ALLMULTI |
 8465				IFF_RUNNING |
 8466				IFF_LOWER_UP |
 8467				IFF_DORMANT)) |
 8468		(dev->gflags & (IFF_PROMISC |
 8469				IFF_ALLMULTI));
 8470
 8471	if (netif_running(dev)) {
 8472		if (netif_oper_up(dev))
 8473			flags |= IFF_RUNNING;
 8474		if (netif_carrier_ok(dev))
 8475			flags |= IFF_LOWER_UP;
 8476		if (netif_dormant(dev))
 8477			flags |= IFF_DORMANT;
 8478	}
 8479
 8480	return flags;
 8481}
 8482EXPORT_SYMBOL(dev_get_flags);
 8483
 8484int __dev_change_flags(struct net_device *dev, unsigned int flags,
 8485		       struct netlink_ext_ack *extack)
 8486{
 8487	unsigned int old_flags = dev->flags;
 8488	int ret;
 8489
 8490	ASSERT_RTNL();
 8491
 8492	/*
 8493	 *	Set the flags on our device.
 8494	 */
 8495
 8496	dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
 8497			       IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
 8498			       IFF_AUTOMEDIA)) |
 8499		     (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
 8500				    IFF_ALLMULTI));
 8501
 8502	/*
 8503	 *	Load in the correct multicast list now the flags have changed.
 8504	 */
 8505
 8506	if ((old_flags ^ flags) & IFF_MULTICAST)
 8507		dev_change_rx_flags(dev, IFF_MULTICAST);
 8508
 8509	dev_set_rx_mode(dev);
 8510
 8511	/*
 8512	 *	Have we downed the interface. We handle IFF_UP ourselves
 8513	 *	according to user attempts to set it, rather than blindly
 8514	 *	setting it.
 8515	 */
 8516
 8517	ret = 0;
 8518	if ((old_flags ^ flags) & IFF_UP) {
 8519		if (old_flags & IFF_UP)
 8520			__dev_close(dev);
 8521		else
 8522			ret = __dev_open(dev, extack);
 8523	}
 8524
 8525	if ((flags ^ dev->gflags) & IFF_PROMISC) {
 8526		int inc = (flags & IFF_PROMISC) ? 1 : -1;
 8527		unsigned int old_flags = dev->flags;
 8528
 8529		dev->gflags ^= IFF_PROMISC;
 8530
 8531		if (__dev_set_promiscuity(dev, inc, false) >= 0)
 8532			if (dev->flags != old_flags)
 8533				dev_set_rx_mode(dev);
 8534	}
 8535
 8536	/* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
 8537	 * is important. Some (broken) drivers set IFF_PROMISC, when
 8538	 * IFF_ALLMULTI is requested not asking us and not reporting.
 8539	 */
 8540	if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
 8541		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
 8542
 8543		dev->gflags ^= IFF_ALLMULTI;
 8544		__dev_set_allmulti(dev, inc, false);
 8545	}
 8546
 8547	return ret;
 8548}
 8549
 8550void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
 8551			unsigned int gchanges, u32 portid,
 8552			const struct nlmsghdr *nlh)
 8553{
 8554	unsigned int changes = dev->flags ^ old_flags;
 8555
 8556	if (gchanges)
 8557		rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC, portid, nlh);
 8558
 8559	if (changes & IFF_UP) {
 8560		if (dev->flags & IFF_UP)
 8561			call_netdevice_notifiers(NETDEV_UP, dev);
 8562		else
 8563			call_netdevice_notifiers(NETDEV_DOWN, dev);
 8564	}
 8565
 8566	if (dev->flags & IFF_UP &&
 8567	    (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
 8568		struct netdev_notifier_change_info change_info = {
 8569			.info = {
 8570				.dev = dev,
 8571			},
 8572			.flags_changed = changes,
 8573		};
 8574
 8575		call_netdevice_notifiers_info(NETDEV_CHANGE, &change_info.info);
 8576	}
 8577}
 8578
 8579/**
 8580 *	dev_change_flags - change device settings
 8581 *	@dev: device
 8582 *	@flags: device state flags
 8583 *	@extack: netlink extended ack
 8584 *
 8585 *	Change settings on device based state flags. The flags are
 8586 *	in the userspace exported format.
 8587 */
 8588int dev_change_flags(struct net_device *dev, unsigned int flags,
 8589		     struct netlink_ext_ack *extack)
 8590{
 8591	int ret;
 8592	unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
 8593
 8594	ret = __dev_change_flags(dev, flags, extack);
 8595	if (ret < 0)
 8596		return ret;
 8597
 8598	changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
 8599	__dev_notify_flags(dev, old_flags, changes, 0, NULL);
 
 
 
 8600	return ret;
 8601}
 8602EXPORT_SYMBOL(dev_change_flags);
 8603
 8604int __dev_set_mtu(struct net_device *dev, int new_mtu)
 8605{
 8606	const struct net_device_ops *ops = dev->netdev_ops;
 8607
 8608	if (ops->ndo_change_mtu)
 8609		return ops->ndo_change_mtu(dev, new_mtu);
 8610
 8611	/* Pairs with all the lockless reads of dev->mtu in the stack */
 8612	WRITE_ONCE(dev->mtu, new_mtu);
 8613	return 0;
 8614}
 8615EXPORT_SYMBOL(__dev_set_mtu);
 8616
 8617int dev_validate_mtu(struct net_device *dev, int new_mtu,
 8618		     struct netlink_ext_ack *extack)
 8619{
 8620	/* MTU must be positive, and in range */
 8621	if (new_mtu < 0 || new_mtu < dev->min_mtu) {
 8622		NL_SET_ERR_MSG(extack, "mtu less than device minimum");
 8623		return -EINVAL;
 8624	}
 8625
 8626	if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) {
 8627		NL_SET_ERR_MSG(extack, "mtu greater than device maximum");
 8628		return -EINVAL;
 8629	}
 8630	return 0;
 8631}
 8632
 8633/**
 8634 *	dev_set_mtu_ext - Change maximum transfer unit
 8635 *	@dev: device
 8636 *	@new_mtu: new transfer unit
 8637 *	@extack: netlink extended ack
 8638 *
 8639 *	Change the maximum transfer size of the network device.
 8640 */
 8641int dev_set_mtu_ext(struct net_device *dev, int new_mtu,
 8642		    struct netlink_ext_ack *extack)
 8643{
 8644	int err, orig_mtu;
 
 8645
 8646	if (new_mtu == dev->mtu)
 8647		return 0;
 8648
 8649	err = dev_validate_mtu(dev, new_mtu, extack);
 8650	if (err)
 8651		return err;
 8652
 8653	if (!netif_device_present(dev))
 8654		return -ENODEV;
 8655
 8656	err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
 8657	err = notifier_to_errno(err);
 8658	if (err)
 8659		return err;
 8660
 8661	orig_mtu = dev->mtu;
 8662	err = __dev_set_mtu(dev, new_mtu);
 8663
 8664	if (!err) {
 8665		err = call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev,
 8666						   orig_mtu);
 8667		err = notifier_to_errno(err);
 8668		if (err) {
 8669			/* setting mtu back and notifying everyone again,
 8670			 * so that they have a chance to revert changes.
 8671			 */
 8672			__dev_set_mtu(dev, orig_mtu);
 8673			call_netdevice_notifiers_mtu(NETDEV_CHANGEMTU, dev,
 8674						     new_mtu);
 8675		}
 8676	}
 8677	return err;
 8678}
 8679
 8680int dev_set_mtu(struct net_device *dev, int new_mtu)
 8681{
 8682	struct netlink_ext_ack extack;
 8683	int err;
 8684
 8685	memset(&extack, 0, sizeof(extack));
 8686	err = dev_set_mtu_ext(dev, new_mtu, &extack);
 8687	if (err && extack._msg)
 8688		net_err_ratelimited("%s: %s\n", dev->name, extack._msg);
 8689	return err;
 8690}
 8691EXPORT_SYMBOL(dev_set_mtu);
 8692
 8693/**
 8694 *	dev_change_tx_queue_len - Change TX queue length of a netdevice
 8695 *	@dev: device
 8696 *	@new_len: new tx queue length
 8697 */
 8698int dev_change_tx_queue_len(struct net_device *dev, unsigned long new_len)
 8699{
 8700	unsigned int orig_len = dev->tx_queue_len;
 8701	int res;
 8702
 8703	if (new_len != (unsigned int)new_len)
 8704		return -ERANGE;
 8705
 8706	if (new_len != orig_len) {
 8707		dev->tx_queue_len = new_len;
 8708		res = call_netdevice_notifiers(NETDEV_CHANGE_TX_QUEUE_LEN, dev);
 8709		res = notifier_to_errno(res);
 8710		if (res)
 8711			goto err_rollback;
 8712		res = dev_qdisc_change_tx_queue_len(dev);
 8713		if (res)
 8714			goto err_rollback;
 8715	}
 8716
 8717	return 0;
 8718
 8719err_rollback:
 8720	netdev_err(dev, "refused to change device tx_queue_len\n");
 8721	dev->tx_queue_len = orig_len;
 8722	return res;
 8723}
 8724
 8725/**
 8726 *	dev_set_group - Change group this device belongs to
 8727 *	@dev: device
 8728 *	@new_group: group this device should belong to
 8729 */
 8730void dev_set_group(struct net_device *dev, int new_group)
 8731{
 8732	dev->group = new_group;
 8733}
 8734
 8735/**
 8736 *	dev_pre_changeaddr_notify - Call NETDEV_PRE_CHANGEADDR.
 8737 *	@dev: device
 8738 *	@addr: new address
 8739 *	@extack: netlink extended ack
 8740 */
 8741int dev_pre_changeaddr_notify(struct net_device *dev, const char *addr,
 8742			      struct netlink_ext_ack *extack)
 8743{
 8744	struct netdev_notifier_pre_changeaddr_info info = {
 8745		.info.dev = dev,
 8746		.info.extack = extack,
 8747		.dev_addr = addr,
 8748	};
 8749	int rc;
 8750
 8751	rc = call_netdevice_notifiers_info(NETDEV_PRE_CHANGEADDR, &info.info);
 8752	return notifier_to_errno(rc);
 8753}
 8754EXPORT_SYMBOL(dev_pre_changeaddr_notify);
 8755
 8756/**
 8757 *	dev_set_mac_address - Change Media Access Control Address
 8758 *	@dev: device
 8759 *	@sa: new address
 8760 *	@extack: netlink extended ack
 8761 *
 8762 *	Change the hardware (MAC) address of the device
 8763 */
 8764int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa,
 8765			struct netlink_ext_ack *extack)
 8766{
 8767	const struct net_device_ops *ops = dev->netdev_ops;
 8768	int err;
 8769
 8770	if (!ops->ndo_set_mac_address)
 8771		return -EOPNOTSUPP;
 8772	if (sa->sa_family != dev->type)
 8773		return -EINVAL;
 8774	if (!netif_device_present(dev))
 8775		return -ENODEV;
 8776	err = dev_pre_changeaddr_notify(dev, sa->sa_data, extack);
 8777	if (err)
 8778		return err;
 8779	err = ops->ndo_set_mac_address(dev, sa);
 8780	if (err)
 8781		return err;
 8782	dev->addr_assign_type = NET_ADDR_SET;
 8783	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
 8784	add_device_randomness(dev->dev_addr, dev->addr_len);
 8785	return 0;
 8786}
 8787EXPORT_SYMBOL(dev_set_mac_address);
 8788
 8789static DECLARE_RWSEM(dev_addr_sem);
 8790
 8791int dev_set_mac_address_user(struct net_device *dev, struct sockaddr *sa,
 8792			     struct netlink_ext_ack *extack)
 8793{
 8794	int ret;
 8795
 8796	down_write(&dev_addr_sem);
 8797	ret = dev_set_mac_address(dev, sa, extack);
 8798	up_write(&dev_addr_sem);
 8799	return ret;
 8800}
 8801EXPORT_SYMBOL(dev_set_mac_address_user);
 8802
 8803int dev_get_mac_address(struct sockaddr *sa, struct net *net, char *dev_name)
 8804{
 8805	size_t size = sizeof(sa->sa_data_min);
 8806	struct net_device *dev;
 8807	int ret = 0;
 8808
 8809	down_read(&dev_addr_sem);
 8810	rcu_read_lock();
 8811
 8812	dev = dev_get_by_name_rcu(net, dev_name);
 8813	if (!dev) {
 8814		ret = -ENODEV;
 8815		goto unlock;
 8816	}
 8817	if (!dev->addr_len)
 8818		memset(sa->sa_data, 0, size);
 8819	else
 8820		memcpy(sa->sa_data, dev->dev_addr,
 8821		       min_t(size_t, size, dev->addr_len));
 8822	sa->sa_family = dev->type;
 8823
 8824unlock:
 8825	rcu_read_unlock();
 8826	up_read(&dev_addr_sem);
 8827	return ret;
 8828}
 8829EXPORT_SYMBOL(dev_get_mac_address);
 8830
 8831/**
 8832 *	dev_change_carrier - Change device carrier
 8833 *	@dev: device
 8834 *	@new_carrier: new value
 8835 *
 8836 *	Change device carrier
 8837 */
 8838int dev_change_carrier(struct net_device *dev, bool new_carrier)
 8839{
 8840	const struct net_device_ops *ops = dev->netdev_ops;
 
 8841
 8842	if (!ops->ndo_change_carrier)
 8843		return -EOPNOTSUPP;
 8844	if (!netif_device_present(dev))
 8845		return -ENODEV;
 8846	return ops->ndo_change_carrier(dev, new_carrier);
 8847}
 8848
 8849/**
 8850 *	dev_get_phys_port_id - Get device physical port ID
 8851 *	@dev: device
 8852 *	@ppid: port ID
 8853 *
 8854 *	Get device physical port ID
 8855 */
 8856int dev_get_phys_port_id(struct net_device *dev,
 8857			 struct netdev_phys_item_id *ppid)
 8858{
 8859	const struct net_device_ops *ops = dev->netdev_ops;
 8860
 8861	if (!ops->ndo_get_phys_port_id)
 8862		return -EOPNOTSUPP;
 8863	return ops->ndo_get_phys_port_id(dev, ppid);
 8864}
 8865
 8866/**
 8867 *	dev_get_phys_port_name - Get device physical port name
 8868 *	@dev: device
 8869 *	@name: port name
 8870 *	@len: limit of bytes to copy to name
 8871 *
 8872 *	Get device physical port name
 8873 */
 8874int dev_get_phys_port_name(struct net_device *dev,
 8875			   char *name, size_t len)
 8876{
 8877	const struct net_device_ops *ops = dev->netdev_ops;
 8878	int err;
 8879
 8880	if (ops->ndo_get_phys_port_name) {
 8881		err = ops->ndo_get_phys_port_name(dev, name, len);
 8882		if (err != -EOPNOTSUPP)
 8883			return err;
 8884	}
 8885	return devlink_compat_phys_port_name_get(dev, name, len);
 8886}
 
 8887
 8888/**
 8889 *	dev_get_port_parent_id - Get the device's port parent identifier
 8890 *	@dev: network device
 8891 *	@ppid: pointer to a storage for the port's parent identifier
 8892 *	@recurse: allow/disallow recursion to lower devices
 8893 *
 8894 *	Get the devices's port parent identifier
 8895 */
 8896int dev_get_port_parent_id(struct net_device *dev,
 8897			   struct netdev_phys_item_id *ppid,
 8898			   bool recurse)
 8899{
 8900	const struct net_device_ops *ops = dev->netdev_ops;
 8901	struct netdev_phys_item_id first = { };
 8902	struct net_device *lower_dev;
 8903	struct list_head *iter;
 8904	int err;
 8905
 8906	if (ops->ndo_get_port_parent_id) {
 8907		err = ops->ndo_get_port_parent_id(dev, ppid);
 8908		if (err != -EOPNOTSUPP)
 8909			return err;
 8910	}
 
 
 
 8911
 8912	err = devlink_compat_switch_id_get(dev, ppid);
 8913	if (!recurse || err != -EOPNOTSUPP)
 8914		return err;
 8915
 8916	netdev_for_each_lower_dev(dev, lower_dev, iter) {
 8917		err = dev_get_port_parent_id(lower_dev, ppid, true);
 8918		if (err)
 8919			break;
 8920		if (!first.id_len)
 8921			first = *ppid;
 8922		else if (memcmp(&first, ppid, sizeof(*ppid)))
 8923			return -EOPNOTSUPP;
 8924	}
 
 
 8925
 
 8926	return err;
 8927}
 8928EXPORT_SYMBOL(dev_get_port_parent_id);
 8929
 8930/**
 8931 *	netdev_port_same_parent_id - Indicate if two network devices have
 8932 *	the same port parent identifier
 8933 *	@a: first network device
 8934 *	@b: second network device
 8935 */
 8936bool netdev_port_same_parent_id(struct net_device *a, struct net_device *b)
 8937{
 8938	struct netdev_phys_item_id a_id = { };
 8939	struct netdev_phys_item_id b_id = { };
 8940
 8941	if (dev_get_port_parent_id(a, &a_id, true) ||
 8942	    dev_get_port_parent_id(b, &b_id, true))
 8943		return false;
 8944
 8945	return netdev_phys_item_id_same(&a_id, &b_id);
 8946}
 8947EXPORT_SYMBOL(netdev_port_same_parent_id);
 8948
 8949/**
 8950 *	dev_change_proto_down - set carrier according to proto_down.
 8951 *
 8952 *	@dev: device
 8953 *	@proto_down: new value
 8954 */
 8955int dev_change_proto_down(struct net_device *dev, bool proto_down)
 8956{
 8957	if (!(dev->priv_flags & IFF_CHANGE_PROTO_DOWN))
 8958		return -EOPNOTSUPP;
 8959	if (!netif_device_present(dev))
 8960		return -ENODEV;
 8961	if (proto_down)
 8962		netif_carrier_off(dev);
 8963	else
 8964		netif_carrier_on(dev);
 8965	dev->proto_down = proto_down;
 8966	return 0;
 8967}
 8968
 8969/**
 8970 *	dev_change_proto_down_reason - proto down reason
 8971 *
 8972 *	@dev: device
 8973 *	@mask: proto down mask
 8974 *	@value: proto down value
 8975 */
 8976void dev_change_proto_down_reason(struct net_device *dev, unsigned long mask,
 8977				  u32 value)
 8978{
 8979	int b;
 8980
 8981	if (!mask) {
 8982		dev->proto_down_reason = value;
 8983	} else {
 8984		for_each_set_bit(b, &mask, 32) {
 8985			if (value & (1 << b))
 8986				dev->proto_down_reason |= BIT(b);
 8987			else
 8988				dev->proto_down_reason &= ~BIT(b);
 8989		}
 8990	}
 8991}
 8992
 8993struct bpf_xdp_link {
 8994	struct bpf_link link;
 8995	struct net_device *dev; /* protected by rtnl_lock, no refcnt held */
 8996	int flags;
 8997};
 8998
 8999static enum bpf_xdp_mode dev_xdp_mode(struct net_device *dev, u32 flags)
 9000{
 9001	if (flags & XDP_FLAGS_HW_MODE)
 9002		return XDP_MODE_HW;
 9003	if (flags & XDP_FLAGS_DRV_MODE)
 9004		return XDP_MODE_DRV;
 9005	if (flags & XDP_FLAGS_SKB_MODE)
 9006		return XDP_MODE_SKB;
 9007	return dev->netdev_ops->ndo_bpf ? XDP_MODE_DRV : XDP_MODE_SKB;
 9008}
 9009
 9010static bpf_op_t dev_xdp_bpf_op(struct net_device *dev, enum bpf_xdp_mode mode)
 9011{
 9012	switch (mode) {
 9013	case XDP_MODE_SKB:
 9014		return generic_xdp_install;
 9015	case XDP_MODE_DRV:
 9016	case XDP_MODE_HW:
 9017		return dev->netdev_ops->ndo_bpf;
 9018	default:
 9019		return NULL;
 9020	}
 9021}
 9022
 9023static struct bpf_xdp_link *dev_xdp_link(struct net_device *dev,
 9024					 enum bpf_xdp_mode mode)
 9025{
 9026	return dev->xdp_state[mode].link;
 9027}
 9028
 9029static struct bpf_prog *dev_xdp_prog(struct net_device *dev,
 9030				     enum bpf_xdp_mode mode)
 9031{
 9032	struct bpf_xdp_link *link = dev_xdp_link(dev, mode);
 9033
 9034	if (link)
 9035		return link->link.prog;
 9036	return dev->xdp_state[mode].prog;
 9037}
 9038
 9039u8 dev_xdp_prog_count(struct net_device *dev)
 9040{
 9041	u8 count = 0;
 9042	int i;
 
 
 
 9043
 9044	for (i = 0; i < __MAX_XDP_MODE; i++)
 9045		if (dev->xdp_state[i].prog || dev->xdp_state[i].link)
 9046			count++;
 9047	return count;
 9048}
 9049EXPORT_SYMBOL_GPL(dev_xdp_prog_count);
 
 9050
 9051u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode)
 9052{
 9053	struct bpf_prog *prog = dev_xdp_prog(dev, mode);
 
 
 
 
 9054
 9055	return prog ? prog->aux->id : 0;
 9056}
 
 
 
 
 
 9057
 9058static void dev_xdp_set_link(struct net_device *dev, enum bpf_xdp_mode mode,
 9059			     struct bpf_xdp_link *link)
 9060{
 9061	dev->xdp_state[mode].link = link;
 9062	dev->xdp_state[mode].prog = NULL;
 9063}
 9064
 9065static void dev_xdp_set_prog(struct net_device *dev, enum bpf_xdp_mode mode,
 9066			     struct bpf_prog *prog)
 9067{
 9068	dev->xdp_state[mode].link = NULL;
 9069	dev->xdp_state[mode].prog = prog;
 9070}
 9071
 9072static int dev_xdp_install(struct net_device *dev, enum bpf_xdp_mode mode,
 9073			   bpf_op_t bpf_op, struct netlink_ext_ack *extack,
 9074			   u32 flags, struct bpf_prog *prog)
 9075{
 9076	struct netdev_bpf xdp;
 9077	int err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 9078
 9079	memset(&xdp, 0, sizeof(xdp));
 9080	xdp.command = mode == XDP_MODE_HW ? XDP_SETUP_PROG_HW : XDP_SETUP_PROG;
 9081	xdp.extack = extack;
 9082	xdp.flags = flags;
 9083	xdp.prog = prog;
 9084
 9085	/* Drivers assume refcnt is already incremented (i.e, prog pointer is
 9086	 * "moved" into driver), so they don't increment it on their own, but
 9087	 * they do decrement refcnt when program is detached or replaced.
 9088	 * Given net_device also owns link/prog, we need to bump refcnt here
 9089	 * to prevent drivers from underflowing it.
 9090	 */
 9091	if (prog)
 9092		bpf_prog_inc(prog);
 9093	err = bpf_op(dev, &xdp);
 9094	if (err) {
 9095		if (prog)
 9096			bpf_prog_put(prog);
 9097		return err;
 9098	}
 9099
 9100	if (mode != XDP_MODE_HW)
 9101		bpf_prog_change_xdp(dev_xdp_prog(dev, mode), prog);
 9102
 9103	return 0;
 9104}
 9105
 9106static void dev_xdp_uninstall(struct net_device *dev)
 9107{
 9108	struct bpf_xdp_link *link;
 9109	struct bpf_prog *prog;
 9110	enum bpf_xdp_mode mode;
 9111	bpf_op_t bpf_op;
 9112
 9113	ASSERT_RTNL();
 9114
 9115	for (mode = XDP_MODE_SKB; mode < __MAX_XDP_MODE; mode++) {
 9116		prog = dev_xdp_prog(dev, mode);
 9117		if (!prog)
 9118			continue;
 9119
 9120		bpf_op = dev_xdp_bpf_op(dev, mode);
 9121		if (!bpf_op)
 9122			continue;
 9123
 9124		WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL));
 9125
 9126		/* auto-detach link from net device */
 9127		link = dev_xdp_link(dev, mode);
 9128		if (link)
 9129			link->dev = NULL;
 9130		else
 9131			bpf_prog_put(prog);
 9132
 9133		dev_xdp_set_link(dev, mode, NULL);
 9134	}
 9135}
 
 
 
 
 
 
 
 
 9136
 9137static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack,
 9138			  struct bpf_xdp_link *link, struct bpf_prog *new_prog,
 9139			  struct bpf_prog *old_prog, u32 flags)
 9140{
 9141	unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES);
 9142	struct bpf_prog *cur_prog;
 9143	struct net_device *upper;
 9144	struct list_head *iter;
 9145	enum bpf_xdp_mode mode;
 9146	bpf_op_t bpf_op;
 9147	int err;
 9148
 9149	ASSERT_RTNL();
 
 
 
 9150
 9151	/* either link or prog attachment, never both */
 9152	if (link && (new_prog || old_prog))
 9153		return -EINVAL;
 9154	/* link supports only XDP mode flags */
 9155	if (link && (flags & ~XDP_FLAGS_MODES)) {
 9156		NL_SET_ERR_MSG(extack, "Invalid XDP flags for BPF link attachment");
 9157		return -EINVAL;
 9158	}
 9159	/* just one XDP mode bit should be set, zero defaults to drv/skb mode */
 9160	if (num_modes > 1) {
 9161		NL_SET_ERR_MSG(extack, "Only one XDP mode flag can be set");
 9162		return -EINVAL;
 9163	}
 9164	/* avoid ambiguity if offload + drv/skb mode progs are both loaded */
 9165	if (!num_modes && dev_xdp_prog_count(dev) > 1) {
 9166		NL_SET_ERR_MSG(extack,
 9167			       "More than one program loaded, unset mode is ambiguous");
 9168		return -EINVAL;
 9169	}
 9170	/* old_prog != NULL implies XDP_FLAGS_REPLACE is set */
 9171	if (old_prog && !(flags & XDP_FLAGS_REPLACE)) {
 9172		NL_SET_ERR_MSG(extack, "XDP_FLAGS_REPLACE is not specified");
 9173		return -EINVAL;
 9174	}
 
 
 9175
 9176	mode = dev_xdp_mode(dev, flags);
 9177	/* can't replace attached link */
 9178	if (dev_xdp_link(dev, mode)) {
 9179		NL_SET_ERR_MSG(extack, "Can't replace active BPF XDP link");
 9180		return -EBUSY;
 9181	}
 9182
 9183	/* don't allow if an upper device already has a program */
 9184	netdev_for_each_upper_dev_rcu(dev, upper, iter) {
 9185		if (dev_xdp_prog_count(upper) > 0) {
 9186			NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program");
 9187			return -EEXIST;
 9188		}
 9189	}
 9190
 9191	cur_prog = dev_xdp_prog(dev, mode);
 9192	/* can't replace attached prog with link */
 9193	if (link && cur_prog) {
 9194		NL_SET_ERR_MSG(extack, "Can't replace active XDP program with BPF link");
 9195		return -EBUSY;
 9196	}
 9197	if ((flags & XDP_FLAGS_REPLACE) && cur_prog != old_prog) {
 9198		NL_SET_ERR_MSG(extack, "Active program does not match expected");
 9199		return -EEXIST;
 9200	}
 9201
 9202	/* put effective new program into new_prog */
 9203	if (link)
 9204		new_prog = link->link.prog;
 9205
 9206	if (new_prog) {
 9207		bool offload = mode == XDP_MODE_HW;
 9208		enum bpf_xdp_mode other_mode = mode == XDP_MODE_SKB
 9209					       ? XDP_MODE_DRV : XDP_MODE_SKB;
 9210
 9211		if ((flags & XDP_FLAGS_UPDATE_IF_NOEXIST) && cur_prog) {
 9212			NL_SET_ERR_MSG(extack, "XDP program already attached");
 9213			return -EBUSY;
 9214		}
 9215		if (!offload && dev_xdp_prog(dev, other_mode)) {
 9216			NL_SET_ERR_MSG(extack, "Native and generic XDP can't be active at the same time");
 9217			return -EEXIST;
 9218		}
 9219		if (!offload && bpf_prog_is_dev_bound(new_prog->aux)) {
 9220			NL_SET_ERR_MSG(extack, "Using device-bound program without HW_MODE flag is not supported");
 9221			return -EINVAL;
 9222		}
 9223		if (new_prog->expected_attach_type == BPF_XDP_DEVMAP) {
 9224			NL_SET_ERR_MSG(extack, "BPF_XDP_DEVMAP programs can not be attached to a device");
 9225			return -EINVAL;
 9226		}
 9227		if (new_prog->expected_attach_type == BPF_XDP_CPUMAP) {
 9228			NL_SET_ERR_MSG(extack, "BPF_XDP_CPUMAP programs can not be attached to a device");
 9229			return -EINVAL;
 
 
 
 
 
 
 9230		}
 9231	}
 9232
 9233	/* don't call drivers if the effective program didn't change */
 9234	if (new_prog != cur_prog) {
 9235		bpf_op = dev_xdp_bpf_op(dev, mode);
 9236		if (!bpf_op) {
 9237			NL_SET_ERR_MSG(extack, "Underlying driver does not support XDP in native mode");
 9238			return -EOPNOTSUPP;
 
 
 
 
 
 9239		}
 
 9240
 9241		err = dev_xdp_install(dev, mode, bpf_op, extack, flags, new_prog);
 9242		if (err)
 9243			return err;
 9244	}
 9245
 9246	if (link)
 9247		dev_xdp_set_link(dev, mode, link);
 9248	else
 9249		dev_xdp_set_prog(dev, mode, new_prog);
 9250	if (cur_prog)
 9251		bpf_prog_put(cur_prog);
 9252
 9253	return 0;
 9254}
 9255
 9256static int dev_xdp_attach_link(struct net_device *dev,
 9257			       struct netlink_ext_ack *extack,
 9258			       struct bpf_xdp_link *link)
 9259{
 9260	return dev_xdp_attach(dev, extack, link, NULL, NULL, link->flags);
 9261}
 9262
 9263static int dev_xdp_detach_link(struct net_device *dev,
 9264			       struct netlink_ext_ack *extack,
 9265			       struct bpf_xdp_link *link)
 9266{
 9267	enum bpf_xdp_mode mode;
 9268	bpf_op_t bpf_op;
 9269
 9270	ASSERT_RTNL();
 9271
 9272	mode = dev_xdp_mode(dev, link->flags);
 9273	if (dev_xdp_link(dev, mode) != link)
 9274		return -EINVAL;
 9275
 9276	bpf_op = dev_xdp_bpf_op(dev, mode);
 9277	WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL));
 9278	dev_xdp_set_link(dev, mode, NULL);
 9279	return 0;
 9280}
 9281
 9282static void bpf_xdp_link_release(struct bpf_link *link)
 9283{
 9284	struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 9285
 9286	rtnl_lock();
 
 
 
 
 
 
 
 9287
 9288	/* if racing with net_device's tear down, xdp_link->dev might be
 9289	 * already NULL, in which case link was already auto-detached
 9290	 */
 9291	if (xdp_link->dev) {
 9292		WARN_ON(dev_xdp_detach_link(xdp_link->dev, NULL, xdp_link));
 9293		xdp_link->dev = NULL;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 9294	}
 9295
 9296	rtnl_unlock();
 9297}
 9298
 9299static int bpf_xdp_link_detach(struct bpf_link *link)
 9300{
 9301	bpf_xdp_link_release(link);
 9302	return 0;
 9303}
 9304
 9305static void bpf_xdp_link_dealloc(struct bpf_link *link)
 
 
 
 
 
 
 
 
 9306{
 9307	struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
 9308
 9309	kfree(xdp_link);
 
 
 
 
 9310}
 9311
 9312static void bpf_xdp_link_show_fdinfo(const struct bpf_link *link,
 9313				     struct seq_file *seq)
 9314{
 9315	struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
 9316	u32 ifindex = 0;
 9317
 9318	rtnl_lock();
 9319	if (xdp_link->dev)
 9320		ifindex = xdp_link->dev->ifindex;
 9321	rtnl_unlock();
 9322
 9323	seq_printf(seq, "ifindex:\t%u\n", ifindex);
 9324}
 9325
 9326static int bpf_xdp_link_fill_link_info(const struct bpf_link *link,
 9327				       struct bpf_link_info *info)
 9328{
 9329	struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
 9330	u32 ifindex = 0;
 9331
 9332	rtnl_lock();
 9333	if (xdp_link->dev)
 9334		ifindex = xdp_link->dev->ifindex;
 9335	rtnl_unlock();
 9336
 9337	info->xdp.ifindex = ifindex;
 9338	return 0;
 9339}
 9340
 9341static int bpf_xdp_link_update(struct bpf_link *link, struct bpf_prog *new_prog,
 9342			       struct bpf_prog *old_prog)
 9343{
 9344	struct bpf_xdp_link *xdp_link = container_of(link, struct bpf_xdp_link, link);
 9345	enum bpf_xdp_mode mode;
 9346	bpf_op_t bpf_op;
 9347	int err = 0;
 9348
 9349	rtnl_lock();
 9350
 9351	/* link might have been auto-released already, so fail */
 9352	if (!xdp_link->dev) {
 9353		err = -ENOLINK;
 9354		goto out_unlock;
 9355	}
 9356
 9357	if (old_prog && link->prog != old_prog) {
 9358		err = -EPERM;
 9359		goto out_unlock;
 9360	}
 9361	old_prog = link->prog;
 9362	if (old_prog->type != new_prog->type ||
 9363	    old_prog->expected_attach_type != new_prog->expected_attach_type) {
 9364		err = -EINVAL;
 9365		goto out_unlock;
 9366	}
 9367
 9368	if (old_prog == new_prog) {
 9369		/* no-op, don't disturb drivers */
 9370		bpf_prog_put(new_prog);
 9371		goto out_unlock;
 
 
 9372	}
 9373
 9374	mode = dev_xdp_mode(xdp_link->dev, xdp_link->flags);
 9375	bpf_op = dev_xdp_bpf_op(xdp_link->dev, mode);
 9376	err = dev_xdp_install(xdp_link->dev, mode, bpf_op, NULL,
 9377			      xdp_link->flags, new_prog);
 9378	if (err)
 9379		goto out_unlock;
 9380
 9381	old_prog = xchg(&link->prog, new_prog);
 9382	bpf_prog_put(old_prog);
 9383
 9384out_unlock:
 9385	rtnl_unlock();
 9386	return err;
 9387}
 9388
 9389static const struct bpf_link_ops bpf_xdp_link_lops = {
 9390	.release = bpf_xdp_link_release,
 9391	.dealloc = bpf_xdp_link_dealloc,
 9392	.detach = bpf_xdp_link_detach,
 9393	.show_fdinfo = bpf_xdp_link_show_fdinfo,
 9394	.fill_link_info = bpf_xdp_link_fill_link_info,
 9395	.update_prog = bpf_xdp_link_update,
 9396};
 9397
 9398int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
 9399{
 9400	struct net *net = current->nsproxy->net_ns;
 9401	struct bpf_link_primer link_primer;
 9402	struct bpf_xdp_link *link;
 9403	struct net_device *dev;
 9404	int err, fd;
 9405
 9406	rtnl_lock();
 9407	dev = dev_get_by_index(net, attr->link_create.target_ifindex);
 9408	if (!dev) {
 9409		rtnl_unlock();
 9410		return -EINVAL;
 9411	}
 9412
 9413	link = kzalloc(sizeof(*link), GFP_USER);
 9414	if (!link) {
 9415		err = -ENOMEM;
 9416		goto unlock;
 9417	}
 9418
 9419	bpf_link_init(&link->link, BPF_LINK_TYPE_XDP, &bpf_xdp_link_lops, prog);
 9420	link->dev = dev;
 9421	link->flags = attr->link_create.flags;
 9422
 9423	err = bpf_link_prime(&link->link, &link_primer);
 9424	if (err) {
 9425		kfree(link);
 9426		goto unlock;
 9427	}
 9428
 9429	err = dev_xdp_attach_link(dev, NULL, link);
 9430	rtnl_unlock();
 
 9431
 9432	if (err) {
 9433		link->dev = NULL;
 9434		bpf_link_cleanup(&link_primer);
 9435		goto out_put_dev;
 9436	}
 9437
 9438	fd = bpf_link_settle(&link_primer);
 9439	/* link itself doesn't hold dev's refcnt to not complicate shutdown */
 9440	dev_put(dev);
 9441	return fd;
 9442
 9443unlock:
 9444	rtnl_unlock();
 
 9445
 9446out_put_dev:
 9447	dev_put(dev);
 9448	return err;
 9449}
 
 9450
 9451/**
 9452 *	dev_change_xdp_fd - set or clear a bpf program for a device rx path
 9453 *	@dev: device
 9454 *	@extack: netlink extended ack
 9455 *	@fd: new program fd or negative value to clear
 9456 *	@expected_fd: old program fd that userspace expects to replace or clear
 9457 *	@flags: xdp-related flags
 9458 *
 9459 *	Set or clear a bpf program for a device
 9460 */
 9461int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,
 9462		      int fd, int expected_fd, u32 flags)
 9463{
 9464	enum bpf_xdp_mode mode = dev_xdp_mode(dev, flags);
 9465	struct bpf_prog *new_prog = NULL, *old_prog = NULL;
 9466	int err;
 9467
 9468	ASSERT_RTNL();
 
 9469
 9470	if (fd >= 0) {
 9471		new_prog = bpf_prog_get_type_dev(fd, BPF_PROG_TYPE_XDP,
 9472						 mode != XDP_MODE_SKB);
 9473		if (IS_ERR(new_prog))
 9474			return PTR_ERR(new_prog);
 9475	}
 9476
 9477	if (expected_fd >= 0) {
 9478		old_prog = bpf_prog_get_type_dev(expected_fd, BPF_PROG_TYPE_XDP,
 9479						 mode != XDP_MODE_SKB);
 9480		if (IS_ERR(old_prog)) {
 9481			err = PTR_ERR(old_prog);
 9482			old_prog = NULL;
 9483			goto err_out;
 9484		}
 9485	}
 9486
 9487	err = dev_xdp_attach(dev, extack, NULL, new_prog, old_prog, flags);
 9488
 9489err_out:
 9490	if (err && new_prog)
 9491		bpf_prog_put(new_prog);
 9492	if (old_prog)
 9493		bpf_prog_put(old_prog);
 9494	return err;
 9495}
 9496
 9497/**
 9498 *	dev_new_index	-	allocate an ifindex
 9499 *	@net: the applicable net namespace
 9500 *
 9501 *	Returns a suitable unique value for a new device interface
 9502 *	number.  The caller must hold the rtnl semaphore or the
 9503 *	dev_base_lock to be sure it remains unique.
 9504 */
 9505static int dev_new_index(struct net *net)
 9506{
 9507	int ifindex = net->ifindex;
 9508
 9509	for (;;) {
 9510		if (++ifindex <= 0)
 9511			ifindex = 1;
 9512		if (!__dev_get_by_index(net, ifindex))
 9513			return net->ifindex = ifindex;
 9514	}
 9515}
 9516
 9517/* Delayed registration/unregisteration */
 9518LIST_HEAD(net_todo_list);
 9519DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
 9520
 9521static void net_set_todo(struct net_device *dev)
 9522{
 9523	list_add_tail(&dev->todo_list, &net_todo_list);
 9524	atomic_inc(&dev_net(dev)->dev_unreg_count);
 9525}
 9526
 9527static netdev_features_t netdev_sync_upper_features(struct net_device *lower,
 9528	struct net_device *upper, netdev_features_t features)
 9529{
 9530	netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
 9531	netdev_features_t feature;
 9532	int feature_bit;
 9533
 9534	for_each_netdev_feature(upper_disables, feature_bit) {
 9535		feature = __NETIF_F_BIT(feature_bit);
 9536		if (!(upper->wanted_features & feature)
 9537		    && (features & feature)) {
 9538			netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n",
 9539				   &feature, upper->name);
 9540			features &= ~feature;
 9541		}
 9542	}
 9543
 9544	return features;
 9545}
 9546
 9547static void netdev_sync_lower_features(struct net_device *upper,
 9548	struct net_device *lower, netdev_features_t features)
 9549{
 9550	netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
 9551	netdev_features_t feature;
 9552	int feature_bit;
 9553
 9554	for_each_netdev_feature(upper_disables, feature_bit) {
 9555		feature = __NETIF_F_BIT(feature_bit);
 9556		if (!(features & feature) && (lower->features & feature)) {
 9557			netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n",
 9558				   &feature, lower->name);
 9559			lower->wanted_features &= ~feature;
 9560			__netdev_update_features(lower);
 9561
 9562			if (unlikely(lower->features & feature))
 9563				netdev_WARN(upper, "failed to disable %pNF on %s!\n",
 9564					    &feature, lower->name);
 9565			else
 9566				netdev_features_change(lower);
 9567		}
 9568	}
 9569}
 9570
 9571static netdev_features_t netdev_fix_features(struct net_device *dev,
 9572	netdev_features_t features)
 9573{
 9574	/* Fix illegal checksum combinations */
 9575	if ((features & NETIF_F_HW_CSUM) &&
 9576	    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
 9577		netdev_warn(dev, "mixed HW and IP checksum settings.\n");
 9578		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
 9579	}
 9580
 9581	/* TSO requires that SG is present as well. */
 9582	if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
 9583		netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
 9584		features &= ~NETIF_F_ALL_TSO;
 9585	}
 9586
 9587	if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
 9588					!(features & NETIF_F_IP_CSUM)) {
 9589		netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
 9590		features &= ~NETIF_F_TSO;
 9591		features &= ~NETIF_F_TSO_ECN;
 
 9592	}
 9593
 9594	if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
 9595					 !(features & NETIF_F_IPV6_CSUM)) {
 9596		netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
 9597		features &= ~NETIF_F_TSO6;
 9598	}
 9599
 9600	/* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */
 9601	if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO))
 9602		features &= ~NETIF_F_TSO_MANGLEID;
 9603
 9604	/* TSO ECN requires that TSO is present as well. */
 9605	if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
 9606		features &= ~NETIF_F_TSO_ECN;
 9607
 9608	/* Software GSO depends on SG. */
 9609	if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
 9610		netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
 9611		features &= ~NETIF_F_GSO;
 9612	}
 9613
 9614	/* GSO partial features require GSO partial be set */
 9615	if ((features & dev->gso_partial_features) &&
 9616	    !(features & NETIF_F_GSO_PARTIAL)) {
 9617		netdev_dbg(dev,
 9618			   "Dropping partially supported GSO features since no GSO partial.\n");
 9619		features &= ~dev->gso_partial_features;
 9620	}
 9621
 9622	if (!(features & NETIF_F_RXCSUM)) {
 9623		/* NETIF_F_GRO_HW implies doing RXCSUM since every packet
 9624		 * successfully merged by hardware must also have the
 9625		 * checksum verified by hardware.  If the user does not
 9626		 * want to enable RXCSUM, logically, we should disable GRO_HW.
 9627		 */
 9628		if (features & NETIF_F_GRO_HW) {
 9629			netdev_dbg(dev, "Dropping NETIF_F_GRO_HW since no RXCSUM feature.\n");
 9630			features &= ~NETIF_F_GRO_HW;
 9631		}
 9632	}
 9633
 9634	/* LRO/HW-GRO features cannot be combined with RX-FCS */
 9635	if (features & NETIF_F_RXFCS) {
 9636		if (features & NETIF_F_LRO) {
 9637			netdev_dbg(dev, "Dropping LRO feature since RX-FCS is requested.\n");
 9638			features &= ~NETIF_F_LRO;
 9639		}
 9640
 9641		if (features & NETIF_F_GRO_HW) {
 9642			netdev_dbg(dev, "Dropping HW-GRO feature since RX-FCS is requested.\n");
 9643			features &= ~NETIF_F_GRO_HW;
 
 9644		}
 9645	}
 9646
 9647	if ((features & NETIF_F_GRO_HW) && (features & NETIF_F_LRO)) {
 9648		netdev_dbg(dev, "Dropping LRO feature since HW-GRO is requested.\n");
 9649		features &= ~NETIF_F_LRO;
 9650	}
 9651
 9652	if (features & NETIF_F_HW_TLS_TX) {
 9653		bool ip_csum = (features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) ==
 9654			(NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM);
 9655		bool hw_csum = features & NETIF_F_HW_CSUM;
 9656
 9657		if (!ip_csum && !hw_csum) {
 9658			netdev_dbg(dev, "Dropping TLS TX HW offload feature since no CSUM feature.\n");
 9659			features &= ~NETIF_F_HW_TLS_TX;
 9660		}
 9661	}
 9662
 9663	if ((features & NETIF_F_HW_TLS_RX) && !(features & NETIF_F_RXCSUM)) {
 9664		netdev_dbg(dev, "Dropping TLS RX HW offload feature since no RXCSUM feature.\n");
 9665		features &= ~NETIF_F_HW_TLS_RX;
 9666	}
 9667
 9668	return features;
 9669}
 9670
 9671int __netdev_update_features(struct net_device *dev)
 9672{
 9673	struct net_device *upper, *lower;
 9674	netdev_features_t features;
 9675	struct list_head *iter;
 9676	int err = -1;
 9677
 9678	ASSERT_RTNL();
 9679
 9680	features = netdev_get_wanted_features(dev);
 9681
 9682	if (dev->netdev_ops->ndo_fix_features)
 9683		features = dev->netdev_ops->ndo_fix_features(dev, features);
 9684
 9685	/* driver might be less strict about feature dependencies */
 9686	features = netdev_fix_features(dev, features);
 9687
 9688	/* some features can't be enabled if they're off on an upper device */
 9689	netdev_for_each_upper_dev_rcu(dev, upper, iter)
 9690		features = netdev_sync_upper_features(dev, upper, features);
 9691
 9692	if (dev->features == features)
 9693		goto sync_lower;
 9694
 9695	netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
 9696		&dev->features, &features);
 9697
 9698	if (dev->netdev_ops->ndo_set_features)
 9699		err = dev->netdev_ops->ndo_set_features(dev, features);
 9700	else
 9701		err = 0;
 9702
 9703	if (unlikely(err < 0)) {
 9704		netdev_err(dev,
 9705			"set_features() failed (%d); wanted %pNF, left %pNF\n",
 9706			err, &features, &dev->features);
 9707		/* return non-0 since some features might have changed and
 9708		 * it's better to fire a spurious notification than miss it
 9709		 */
 9710		return -1;
 9711	}
 9712
 9713sync_lower:
 9714	/* some features must be disabled on lower devices when disabled
 9715	 * on an upper device (think: bonding master or bridge)
 9716	 */
 9717	netdev_for_each_lower_dev(dev, lower, iter)
 9718		netdev_sync_lower_features(dev, lower, features);
 9719
 9720	if (!err) {
 9721		netdev_features_t diff = features ^ dev->features;
 9722
 9723		if (diff & NETIF_F_RX_UDP_TUNNEL_PORT) {
 9724			/* udp_tunnel_{get,drop}_rx_info both need
 9725			 * NETIF_F_RX_UDP_TUNNEL_PORT enabled on the
 9726			 * device, or they won't do anything.
 9727			 * Thus we need to update dev->features
 9728			 * *before* calling udp_tunnel_get_rx_info,
 9729			 * but *after* calling udp_tunnel_drop_rx_info.
 9730			 */
 9731			if (features & NETIF_F_RX_UDP_TUNNEL_PORT) {
 9732				dev->features = features;
 9733				udp_tunnel_get_rx_info(dev);
 9734			} else {
 9735				udp_tunnel_drop_rx_info(dev);
 9736			}
 9737		}
 9738
 9739		if (diff & NETIF_F_HW_VLAN_CTAG_FILTER) {
 9740			if (features & NETIF_F_HW_VLAN_CTAG_FILTER) {
 9741				dev->features = features;
 9742				err |= vlan_get_rx_ctag_filter_info(dev);
 9743			} else {
 9744				vlan_drop_rx_ctag_filter_info(dev);
 9745			}
 9746		}
 9747
 9748		if (diff & NETIF_F_HW_VLAN_STAG_FILTER) {
 9749			if (features & NETIF_F_HW_VLAN_STAG_FILTER) {
 9750				dev->features = features;
 9751				err |= vlan_get_rx_stag_filter_info(dev);
 9752			} else {
 9753				vlan_drop_rx_stag_filter_info(dev);
 9754			}
 9755		}
 9756
 9757		dev->features = features;
 9758	}
 9759
 9760	return err < 0 ? 0 : 1;
 9761}
 9762
 9763/**
 9764 *	netdev_update_features - recalculate device features
 9765 *	@dev: the device to check
 9766 *
 9767 *	Recalculate dev->features set and send notifications if it
 9768 *	has changed. Should be called after driver or hardware dependent
 9769 *	conditions might have changed that influence the features.
 9770 */
 9771void netdev_update_features(struct net_device *dev)
 9772{
 9773	if (__netdev_update_features(dev))
 9774		netdev_features_change(dev);
 9775}
 9776EXPORT_SYMBOL(netdev_update_features);
 9777
 9778/**
 9779 *	netdev_change_features - recalculate device features
 9780 *	@dev: the device to check
 9781 *
 9782 *	Recalculate dev->features set and send notifications even
 9783 *	if they have not changed. Should be called instead of
 9784 *	netdev_update_features() if also dev->vlan_features might
 9785 *	have changed to allow the changes to be propagated to stacked
 9786 *	VLAN devices.
 9787 */
 9788void netdev_change_features(struct net_device *dev)
 9789{
 9790	__netdev_update_features(dev);
 9791	netdev_features_change(dev);
 9792}
 9793EXPORT_SYMBOL(netdev_change_features);
 9794
 9795/**
 9796 *	netif_stacked_transfer_operstate -	transfer operstate
 9797 *	@rootdev: the root or lower level device to transfer state from
 9798 *	@dev: the device to transfer operstate to
 9799 *
 9800 *	Transfer operational state from root to device. This is normally
 9801 *	called when a stacking relationship exists between the root
 9802 *	device and the device(a leaf device).
 9803 */
 9804void netif_stacked_transfer_operstate(const struct net_device *rootdev,
 9805					struct net_device *dev)
 9806{
 9807	if (rootdev->operstate == IF_OPER_DORMANT)
 9808		netif_dormant_on(dev);
 9809	else
 9810		netif_dormant_off(dev);
 9811
 9812	if (rootdev->operstate == IF_OPER_TESTING)
 9813		netif_testing_on(dev);
 9814	else
 9815		netif_testing_off(dev);
 9816
 9817	if (netif_carrier_ok(rootdev))
 9818		netif_carrier_on(dev);
 9819	else
 9820		netif_carrier_off(dev);
 9821}
 9822EXPORT_SYMBOL(netif_stacked_transfer_operstate);
 9823
 
 9824static int netif_alloc_rx_queues(struct net_device *dev)
 9825{
 9826	unsigned int i, count = dev->num_rx_queues;
 9827	struct netdev_rx_queue *rx;
 9828	size_t sz = count * sizeof(*rx);
 9829	int err = 0;
 9830
 9831	BUG_ON(count < 1);
 9832
 9833	rx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);
 9834	if (!rx)
 
 9835		return -ENOMEM;
 9836
 9837	dev->_rx = rx;
 9838
 9839	for (i = 0; i < count; i++) {
 9840		rx[i].dev = dev;
 9841
 9842		/* XDP RX-queue setup */
 9843		err = xdp_rxq_info_reg(&rx[i].xdp_rxq, dev, i, 0);
 9844		if (err < 0)
 9845			goto err_rxq_info;
 9846	}
 9847	return 0;
 9848
 9849err_rxq_info:
 9850	/* Rollback successful reg's and free other resources */
 9851	while (i--)
 9852		xdp_rxq_info_unreg(&rx[i].xdp_rxq);
 9853	kvfree(dev->_rx);
 9854	dev->_rx = NULL;
 9855	return err;
 9856}
 9857
 9858static void netif_free_rx_queues(struct net_device *dev)
 9859{
 9860	unsigned int i, count = dev->num_rx_queues;
 9861
 9862	/* netif_alloc_rx_queues alloc failed, resources have been unreg'ed */
 9863	if (!dev->_rx)
 9864		return;
 9865
 9866	for (i = 0; i < count; i++)
 9867		xdp_rxq_info_unreg(&dev->_rx[i].xdp_rxq);
 9868
 9869	kvfree(dev->_rx);
 9870}
 
 9871
 9872static void netdev_init_one_queue(struct net_device *dev,
 9873				  struct netdev_queue *queue, void *_unused)
 9874{
 9875	/* Initialize queue lock */
 9876	spin_lock_init(&queue->_xmit_lock);
 9877	netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
 9878	queue->xmit_lock_owner = -1;
 9879	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
 9880	queue->dev = dev;
 9881#ifdef CONFIG_BQL
 9882	dql_init(&queue->dql, HZ);
 9883#endif
 9884}
 9885
 9886static void netif_free_tx_queues(struct net_device *dev)
 9887{
 9888	kvfree(dev->_tx);
 9889}
 9890
 9891static int netif_alloc_netdev_queues(struct net_device *dev)
 9892{
 9893	unsigned int count = dev->num_tx_queues;
 9894	struct netdev_queue *tx;
 9895	size_t sz = count * sizeof(*tx);
 9896
 9897	if (count < 1 || count > 0xffff)
 9898		return -EINVAL;
 9899
 9900	tx = kvzalloc(sz, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);
 9901	if (!tx)
 
 
 9902		return -ENOMEM;
 9903
 9904	dev->_tx = tx;
 9905
 9906	netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
 9907	spin_lock_init(&dev->tx_global_lock);
 9908
 9909	return 0;
 9910}
 9911
 9912void netif_tx_stop_all_queues(struct net_device *dev)
 9913{
 9914	unsigned int i;
 9915
 9916	for (i = 0; i < dev->num_tx_queues; i++) {
 9917		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
 9918
 9919		netif_tx_stop_queue(txq);
 9920	}
 9921}
 9922EXPORT_SYMBOL(netif_tx_stop_all_queues);
 9923
 9924/**
 9925 * register_netdevice() - register a network device
 9926 * @dev: device to register
 9927 *
 9928 * Take a prepared network device structure and make it externally accessible.
 9929 * A %NETDEV_REGISTER message is sent to the netdev notifier chain.
 9930 * Callers must hold the rtnl lock - you may want register_netdev()
 9931 * instead of this.
 
 
 
 
 
 
 
 9932 */
 
 9933int register_netdevice(struct net_device *dev)
 9934{
 9935	int ret;
 9936	struct net *net = dev_net(dev);
 9937
 9938	BUILD_BUG_ON(sizeof(netdev_features_t) * BITS_PER_BYTE <
 9939		     NETDEV_FEATURE_COUNT);
 9940	BUG_ON(dev_boot_phase);
 9941	ASSERT_RTNL();
 9942
 9943	might_sleep();
 9944
 9945	/* When net_device's are persistent, this will be fatal. */
 9946	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
 9947	BUG_ON(!net);
 9948
 9949	ret = ethtool_check_ops(dev->ethtool_ops);
 9950	if (ret)
 9951		return ret;
 9952
 9953	spin_lock_init(&dev->addr_list_lock);
 9954	netdev_set_addr_lockdep_class(dev);
 9955
 9956	ret = dev_get_valid_name(net, dev, dev->name);
 9957	if (ret < 0)
 9958		goto out;
 9959
 9960	ret = -ENOMEM;
 9961	dev->name_node = netdev_name_node_head_alloc(dev);
 9962	if (!dev->name_node)
 9963		goto out;
 9964
 9965	/* Init, if this function is available */
 9966	if (dev->netdev_ops->ndo_init) {
 9967		ret = dev->netdev_ops->ndo_init(dev);
 9968		if (ret) {
 9969			if (ret > 0)
 9970				ret = -EIO;
 9971			goto err_free_name;
 9972		}
 9973	}
 9974
 9975	if (((dev->hw_features | dev->features) &
 9976	     NETIF_F_HW_VLAN_CTAG_FILTER) &&
 9977	    (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
 9978	     !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
 9979		netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
 9980		ret = -EINVAL;
 9981		goto err_uninit;
 9982	}
 9983
 9984	ret = -EBUSY;
 9985	if (!dev->ifindex)
 9986		dev->ifindex = dev_new_index(net);
 9987	else if (__dev_get_by_index(net, dev->ifindex))
 9988		goto err_uninit;
 9989
 9990	/* Transfer changeable features to wanted_features and enable
 9991	 * software offloads (GSO and GRO).
 9992	 */
 9993	dev->hw_features |= (NETIF_F_SOFT_FEATURES | NETIF_F_SOFT_FEATURES_OFF);
 9994	dev->features |= NETIF_F_SOFT_FEATURES;
 9995
 9996	if (dev->udp_tunnel_nic_info) {
 9997		dev->features |= NETIF_F_RX_UDP_TUNNEL_PORT;
 9998		dev->hw_features |= NETIF_F_RX_UDP_TUNNEL_PORT;
 9999	}
10000
10001	dev->wanted_features = dev->features & dev->hw_features;
10002
10003	if (!(dev->flags & IFF_LOOPBACK))
10004		dev->hw_features |= NETIF_F_NOCACHE_COPY;
10005
10006	/* If IPv4 TCP segmentation offload is supported we should also
10007	 * allow the device to enable segmenting the frame with the option
10008	 * of ignoring a static IP ID value.  This doesn't enable the
10009	 * feature itself but allows the user to enable it later.
10010	 */
10011	if (dev->hw_features & NETIF_F_TSO)
10012		dev->hw_features |= NETIF_F_TSO_MANGLEID;
10013	if (dev->vlan_features & NETIF_F_TSO)
10014		dev->vlan_features |= NETIF_F_TSO_MANGLEID;
10015	if (dev->mpls_features & NETIF_F_TSO)
10016		dev->mpls_features |= NETIF_F_TSO_MANGLEID;
10017	if (dev->hw_enc_features & NETIF_F_TSO)
10018		dev->hw_enc_features |= NETIF_F_TSO_MANGLEID;
10019
10020	/* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
10021	 */
10022	dev->vlan_features |= NETIF_F_HIGHDMA;
10023
10024	/* Make NETIF_F_SG inheritable to tunnel devices.
10025	 */
10026	dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL;
10027
10028	/* Make NETIF_F_SG inheritable to MPLS.
10029	 */
10030	dev->mpls_features |= NETIF_F_SG;
10031
10032	ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
10033	ret = notifier_to_errno(ret);
10034	if (ret)
10035		goto err_uninit;
10036
10037	ret = netdev_register_kobject(dev);
10038	write_lock(&dev_base_lock);
10039	dev->reg_state = ret ? NETREG_UNREGISTERED : NETREG_REGISTERED;
10040	write_unlock(&dev_base_lock);
10041	if (ret)
10042		goto err_uninit_notify;
 
10043
10044	__netdev_update_features(dev);
10045
10046	/*
10047	 *	Default initial state at registry is that the
10048	 *	device is present.
10049	 */
10050
10051	set_bit(__LINK_STATE_PRESENT, &dev->state);
10052
10053	linkwatch_init_dev(dev);
10054
10055	dev_init_scheduler(dev);
10056
10057	netdev_hold(dev, &dev->dev_registered_tracker, GFP_KERNEL);
10058	list_netdevice(dev);
10059
10060	add_device_randomness(dev->dev_addr, dev->addr_len);
10061
10062	/* If the device has permanent device address, driver should
10063	 * set dev_addr and also addr_assign_type should be set to
10064	 * NET_ADDR_PERM (default value).
10065	 */
10066	if (dev->addr_assign_type == NET_ADDR_PERM)
10067		memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
10068
10069	/* Notify protocols, that a new device appeared. */
10070	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
10071	ret = notifier_to_errno(ret);
10072	if (ret) {
10073		/* Expect explicit free_netdev() on failure */
10074		dev->needs_free_netdev = false;
10075		unregister_netdevice_queue(dev, NULL);
10076		goto out;
10077	}
10078	/*
10079	 *	Prevent userspace races by waiting until the network
10080	 *	device is fully setup before sending notifications.
10081	 */
10082	if (!dev->rtnl_link_ops ||
10083	    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
10084		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL);
10085
10086out:
10087	return ret;
10088
10089err_uninit_notify:
10090	call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev);
10091err_uninit:
10092	if (dev->netdev_ops->ndo_uninit)
10093		dev->netdev_ops->ndo_uninit(dev);
10094	if (dev->priv_destructor)
10095		dev->priv_destructor(dev);
10096err_free_name:
10097	netdev_name_node_free(dev->name_node);
10098	goto out;
10099}
10100EXPORT_SYMBOL(register_netdevice);
10101
10102/**
10103 *	init_dummy_netdev	- init a dummy network device for NAPI
10104 *	@dev: device to init
10105 *
10106 *	This takes a network device structure and initialize the minimum
10107 *	amount of fields so it can be used to schedule NAPI polls without
10108 *	registering a full blown interface. This is to be used by drivers
10109 *	that need to tie several hardware interfaces to a single NAPI
10110 *	poll scheduler due to HW limitations.
10111 */
10112int init_dummy_netdev(struct net_device *dev)
10113{
10114	/* Clear everything. Note we don't initialize spinlocks
10115	 * are they aren't supposed to be taken by any of the
10116	 * NAPI code and this dummy netdev is supposed to be
10117	 * only ever used for NAPI polls
10118	 */
10119	memset(dev, 0, sizeof(struct net_device));
10120
10121	/* make sure we BUG if trying to hit standard
10122	 * register/unregister code path
10123	 */
10124	dev->reg_state = NETREG_DUMMY;
10125
10126	/* NAPI wants this */
10127	INIT_LIST_HEAD(&dev->napi_list);
10128
10129	/* a dummy interface is started by default */
10130	set_bit(__LINK_STATE_PRESENT, &dev->state);
10131	set_bit(__LINK_STATE_START, &dev->state);
10132
10133	/* napi_busy_loop stats accounting wants this */
10134	dev_net_set(dev, &init_net);
10135
10136	/* Note : We dont allocate pcpu_refcnt for dummy devices,
10137	 * because users of this 'device' dont need to change
10138	 * its refcount.
10139	 */
10140
10141	return 0;
10142}
10143EXPORT_SYMBOL_GPL(init_dummy_netdev);
10144
10145
10146/**
10147 *	register_netdev	- register a network device
10148 *	@dev: device to register
10149 *
10150 *	Take a completed network device structure and add it to the kernel
10151 *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
10152 *	chain. 0 is returned on success. A negative errno code is returned
10153 *	on a failure to set up the device, or if the name is a duplicate.
10154 *
10155 *	This is a wrapper around register_netdevice that takes the rtnl semaphore
10156 *	and expands the device name if you passed a format string to
10157 *	alloc_netdev.
10158 */
10159int register_netdev(struct net_device *dev)
10160{
10161	int err;
10162
10163	if (rtnl_lock_killable())
10164		return -EINTR;
10165	err = register_netdevice(dev);
10166	rtnl_unlock();
10167	return err;
10168}
10169EXPORT_SYMBOL(register_netdev);
10170
10171int netdev_refcnt_read(const struct net_device *dev)
10172{
10173#ifdef CONFIG_PCPU_DEV_REFCNT
10174	int i, refcnt = 0;
10175
10176	for_each_possible_cpu(i)
10177		refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
10178	return refcnt;
10179#else
10180	return refcount_read(&dev->dev_refcnt);
10181#endif
10182}
10183EXPORT_SYMBOL(netdev_refcnt_read);
10184
10185int netdev_unregister_timeout_secs __read_mostly = 10;
10186
10187#define WAIT_REFS_MIN_MSECS 1
10188#define WAIT_REFS_MAX_MSECS 250
10189/**
10190 * netdev_wait_allrefs_any - wait until all references are gone.
10191 * @list: list of net_devices to wait on
10192 *
10193 * This is called when unregistering network devices.
10194 *
10195 * Any protocol or device that holds a reference should register
10196 * for netdevice notification, and cleanup and put back the
10197 * reference if they receive an UNREGISTER event.
10198 * We can get stuck here if buggy protocols don't correctly
10199 * call dev_put.
10200 */
10201static struct net_device *netdev_wait_allrefs_any(struct list_head *list)
10202{
10203	unsigned long rebroadcast_time, warning_time;
10204	struct net_device *dev;
10205	int wait = 0;
10206
10207	rebroadcast_time = warning_time = jiffies;
10208
10209	list_for_each_entry(dev, list, todo_list)
10210		if (netdev_refcnt_read(dev) == 1)
10211			return dev;
10212
10213	while (true) {
10214		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
10215			rtnl_lock();
10216
10217			/* Rebroadcast unregister notification */
10218			list_for_each_entry(dev, list, todo_list)
10219				call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
10220
10221			__rtnl_unlock();
10222			rcu_barrier();
10223			rtnl_lock();
10224
10225			list_for_each_entry(dev, list, todo_list)
10226				if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
10227					     &dev->state)) {
10228					/* We must not have linkwatch events
10229					 * pending on unregister. If this
10230					 * happens, we simply run the queue
10231					 * unscheduled, resulting in a noop
10232					 * for this device.
10233					 */
10234					linkwatch_run_queue();
10235					break;
10236				}
10237
10238			__rtnl_unlock();
10239
10240			rebroadcast_time = jiffies;
10241		}
10242
10243		if (!wait) {
10244			rcu_barrier();
10245			wait = WAIT_REFS_MIN_MSECS;
10246		} else {
10247			msleep(wait);
10248			wait = min(wait << 1, WAIT_REFS_MAX_MSECS);
10249		}
10250
10251		list_for_each_entry(dev, list, todo_list)
10252			if (netdev_refcnt_read(dev) == 1)
10253				return dev;
10254
10255		if (time_after(jiffies, warning_time +
10256			       READ_ONCE(netdev_unregister_timeout_secs) * HZ)) {
10257			list_for_each_entry(dev, list, todo_list) {
10258				pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
10259					 dev->name, netdev_refcnt_read(dev));
10260				ref_tracker_dir_print(&dev->refcnt_tracker, 10);
10261			}
10262
 
 
 
 
 
10263			warning_time = jiffies;
10264		}
10265	}
10266}
10267
10268/* The sequence is:
10269 *
10270 *	rtnl_lock();
10271 *	...
10272 *	register_netdevice(x1);
10273 *	register_netdevice(x2);
10274 *	...
10275 *	unregister_netdevice(y1);
10276 *	unregister_netdevice(y2);
10277 *      ...
10278 *	rtnl_unlock();
10279 *	free_netdev(y1);
10280 *	free_netdev(y2);
10281 *
10282 * We are invoked by rtnl_unlock().
10283 * This allows us to deal with problems:
10284 * 1) We can delete sysfs objects which invoke hotplug
10285 *    without deadlocking with linkwatch via keventd.
10286 * 2) Since we run with the RTNL semaphore not held, we can sleep
10287 *    safely in order to wait for the netdev refcnt to drop to zero.
10288 *
10289 * We must not return until all unregister events added during
10290 * the interval the lock was held have been completed.
10291 */
10292void netdev_run_todo(void)
10293{
10294	struct net_device *dev, *tmp;
10295	struct list_head list;
10296#ifdef CONFIG_LOCKDEP
10297	struct list_head unlink_list;
10298
10299	list_replace_init(&net_unlink_list, &unlink_list);
10300
10301	while (!list_empty(&unlink_list)) {
10302		struct net_device *dev = list_first_entry(&unlink_list,
10303							  struct net_device,
10304							  unlink_list);
10305		list_del_init(&dev->unlink_list);
10306		dev->nested_level = dev->lower_level - 1;
10307	}
10308#endif
10309
10310	/* Snapshot list, allow later requests */
10311	list_replace_init(&net_todo_list, &list);
10312
10313	__rtnl_unlock();
10314
10315	/* Wait for rcu callbacks to finish before next phase */
10316	if (!list_empty(&list))
10317		rcu_barrier();
 
10318
10319	list_for_each_entry_safe(dev, tmp, &list, todo_list) {
10320		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
10321			netdev_WARN(dev, "run_todo but not unregistering\n");
10322			list_del(&dev->todo_list);
 
10323			continue;
10324		}
10325
10326		write_lock(&dev_base_lock);
10327		dev->reg_state = NETREG_UNREGISTERED;
10328		write_unlock(&dev_base_lock);
10329		linkwatch_forget_dev(dev);
10330	}
10331
10332	while (!list_empty(&list)) {
10333		dev = netdev_wait_allrefs_any(&list);
10334		list_del(&dev->todo_list);
10335
10336		/* paranoia */
10337		BUG_ON(netdev_refcnt_read(dev) != 1);
10338		BUG_ON(!list_empty(&dev->ptype_all));
10339		BUG_ON(!list_empty(&dev->ptype_specific));
10340		WARN_ON(rcu_access_pointer(dev->ip_ptr));
10341		WARN_ON(rcu_access_pointer(dev->ip6_ptr));
10342
10343		if (dev->priv_destructor)
10344			dev->priv_destructor(dev);
10345		if (dev->needs_free_netdev)
10346			free_netdev(dev);
10347
10348		if (atomic_dec_and_test(&dev_net(dev)->dev_unreg_count))
10349			wake_up(&netdev_unregistering_wq);
10350
10351		/* Free network device */
10352		kobject_put(&dev->dev.kobj);
10353	}
10354}
10355
10356/* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has
10357 * all the same fields in the same order as net_device_stats, with only
10358 * the type differing, but rtnl_link_stats64 may have additional fields
10359 * at the end for newer counters.
10360 */
10361void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
10362			     const struct net_device_stats *netdev_stats)
10363{
10364	size_t i, n = sizeof(*netdev_stats) / sizeof(atomic_long_t);
10365	const atomic_long_t *src = (atomic_long_t *)netdev_stats;
 
 
 
 
10366	u64 *dst = (u64 *)stats64;
10367
10368	BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64));
 
10369	for (i = 0; i < n; i++)
10370		dst[i] = (unsigned long)atomic_long_read(&src[i]);
10371	/* zero out counters that only exist in rtnl_link_stats64 */
10372	memset((char *)stats64 + n * sizeof(u64), 0,
10373	       sizeof(*stats64) - n * sizeof(u64));
10374}
10375EXPORT_SYMBOL(netdev_stats_to_stats64);
10376
10377struct net_device_core_stats __percpu *netdev_core_stats_alloc(struct net_device *dev)
10378{
10379	struct net_device_core_stats __percpu *p;
10380
10381	p = alloc_percpu_gfp(struct net_device_core_stats,
10382			     GFP_ATOMIC | __GFP_NOWARN);
10383
10384	if (p && cmpxchg(&dev->core_stats, NULL, p))
10385		free_percpu(p);
10386
10387	/* This READ_ONCE() pairs with the cmpxchg() above */
10388	return READ_ONCE(dev->core_stats);
10389}
10390EXPORT_SYMBOL(netdev_core_stats_alloc);
10391
10392/**
10393 *	dev_get_stats	- get network device statistics
10394 *	@dev: device to get statistics from
10395 *	@storage: place to store stats
10396 *
10397 *	Get network statistics from device. Return @storage.
10398 *	The device driver may provide its own method by setting
10399 *	dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
10400 *	otherwise the internal statistics structure is used.
10401 */
10402struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
10403					struct rtnl_link_stats64 *storage)
10404{
10405	const struct net_device_ops *ops = dev->netdev_ops;
10406	const struct net_device_core_stats __percpu *p;
10407
10408	if (ops->ndo_get_stats64) {
10409		memset(storage, 0, sizeof(*storage));
10410		ops->ndo_get_stats64(dev, storage);
10411	} else if (ops->ndo_get_stats) {
10412		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
10413	} else {
10414		netdev_stats_to_stats64(storage, &dev->stats);
10415	}
10416
10417	/* This READ_ONCE() pairs with the write in netdev_core_stats_alloc() */
10418	p = READ_ONCE(dev->core_stats);
10419	if (p) {
10420		const struct net_device_core_stats *core_stats;
10421		int i;
10422
10423		for_each_possible_cpu(i) {
10424			core_stats = per_cpu_ptr(p, i);
10425			storage->rx_dropped += READ_ONCE(core_stats->rx_dropped);
10426			storage->tx_dropped += READ_ONCE(core_stats->tx_dropped);
10427			storage->rx_nohandler += READ_ONCE(core_stats->rx_nohandler);
10428			storage->rx_otherhost_dropped += READ_ONCE(core_stats->rx_otherhost_dropped);
10429		}
10430	}
10431	return storage;
10432}
10433EXPORT_SYMBOL(dev_get_stats);
10434
10435/**
10436 *	dev_fetch_sw_netstats - get per-cpu network device statistics
10437 *	@s: place to store stats
10438 *	@netstats: per-cpu network stats to read from
10439 *
10440 *	Read per-cpu network statistics and populate the related fields in @s.
10441 */
10442void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s,
10443			   const struct pcpu_sw_netstats __percpu *netstats)
10444{
10445	int cpu;
10446
10447	for_each_possible_cpu(cpu) {
10448		u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
10449		const struct pcpu_sw_netstats *stats;
10450		unsigned int start;
10451
10452		stats = per_cpu_ptr(netstats, cpu);
10453		do {
10454			start = u64_stats_fetch_begin(&stats->syncp);
10455			rx_packets = u64_stats_read(&stats->rx_packets);
10456			rx_bytes   = u64_stats_read(&stats->rx_bytes);
10457			tx_packets = u64_stats_read(&stats->tx_packets);
10458			tx_bytes   = u64_stats_read(&stats->tx_bytes);
10459		} while (u64_stats_fetch_retry(&stats->syncp, start));
10460
10461		s->rx_packets += rx_packets;
10462		s->rx_bytes   += rx_bytes;
10463		s->tx_packets += tx_packets;
10464		s->tx_bytes   += tx_bytes;
10465	}
10466}
10467EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats);
10468
10469/**
10470 *	dev_get_tstats64 - ndo_get_stats64 implementation
10471 *	@dev: device to get statistics from
10472 *	@s: place to store stats
10473 *
10474 *	Populate @s from dev->stats and dev->tstats. Can be used as
10475 *	ndo_get_stats64() callback.
10476 */
10477void dev_get_tstats64(struct net_device *dev, struct rtnl_link_stats64 *s)
10478{
10479	netdev_stats_to_stats64(s, &dev->stats);
10480	dev_fetch_sw_netstats(s, dev->tstats);
10481}
10482EXPORT_SYMBOL_GPL(dev_get_tstats64);
10483
10484struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
10485{
10486	struct netdev_queue *queue = dev_ingress_queue(dev);
10487
10488#ifdef CONFIG_NET_CLS_ACT
10489	if (queue)
10490		return queue;
10491	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
10492	if (!queue)
10493		return NULL;
10494	netdev_init_one_queue(dev, queue, NULL);
10495	RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
10496	queue->qdisc_sleeping = &noop_qdisc;
10497	rcu_assign_pointer(dev->ingress_queue, queue);
10498#endif
10499	return queue;
10500}
10501
10502static const struct ethtool_ops default_ethtool_ops;
10503
10504void netdev_set_default_ethtool_ops(struct net_device *dev,
10505				    const struct ethtool_ops *ops)
10506{
10507	if (dev->ethtool_ops == &default_ethtool_ops)
10508		dev->ethtool_ops = ops;
10509}
10510EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
10511
10512/**
10513 * netdev_sw_irq_coalesce_default_on() - enable SW IRQ coalescing by default
10514 * @dev: netdev to enable the IRQ coalescing on
10515 *
10516 * Sets a conservative default for SW IRQ coalescing. Users can use
10517 * sysfs attributes to override the default values.
10518 */
10519void netdev_sw_irq_coalesce_default_on(struct net_device *dev)
10520{
10521	WARN_ON(dev->reg_state == NETREG_REGISTERED);
10522
10523	dev->gro_flush_timeout = 20000;
10524	dev->napi_defer_hard_irqs = 1;
10525}
10526EXPORT_SYMBOL_GPL(netdev_sw_irq_coalesce_default_on);
10527
10528void netdev_freemem(struct net_device *dev)
10529{
10530	char *addr = (char *)dev - dev->padded;
10531
10532	kvfree(addr);
10533}
10534
10535/**
10536 * alloc_netdev_mqs - allocate network device
10537 * @sizeof_priv: size of private data to allocate space for
10538 * @name: device name format string
10539 * @name_assign_type: origin of device name
10540 * @setup: callback to initialize device
10541 * @txqs: the number of TX subqueues to allocate
10542 * @rxqs: the number of RX subqueues to allocate
10543 *
10544 * Allocates a struct net_device with private data area for driver use
10545 * and performs basic initialization.  Also allocates subqueue structs
10546 * for each queue on the device.
10547 */
10548struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
10549		unsigned char name_assign_type,
10550		void (*setup)(struct net_device *),
10551		unsigned int txqs, unsigned int rxqs)
10552{
10553	struct net_device *dev;
10554	unsigned int alloc_size;
10555	struct net_device *p;
10556
10557	BUG_ON(strlen(name) >= sizeof(dev->name));
10558
10559	if (txqs < 1) {
10560		pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
 
10561		return NULL;
10562	}
10563
 
10564	if (rxqs < 1) {
10565		pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
 
10566		return NULL;
10567	}
 
10568
10569	alloc_size = sizeof(struct net_device);
10570	if (sizeof_priv) {
10571		/* ensure 32-byte alignment of private area */
10572		alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
10573		alloc_size += sizeof_priv;
10574	}
10575	/* ensure 32-byte alignment of whole construct */
10576	alloc_size += NETDEV_ALIGN - 1;
10577
10578	p = kvzalloc(alloc_size, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);
10579	if (!p)
 
10580		return NULL;
 
10581
10582	dev = PTR_ALIGN(p, NETDEV_ALIGN);
10583	dev->padded = (char *)dev - (char *)p;
10584
10585	ref_tracker_dir_init(&dev->refcnt_tracker, 128);
10586#ifdef CONFIG_PCPU_DEV_REFCNT
10587	dev->pcpu_refcnt = alloc_percpu(int);
10588	if (!dev->pcpu_refcnt)
10589		goto free_dev;
10590	__dev_hold(dev);
10591#else
10592	refcount_set(&dev->dev_refcnt, 1);
10593#endif
10594
10595	if (dev_addr_init(dev))
10596		goto free_pcpu;
10597
10598	dev_mc_init(dev);
10599	dev_uc_init(dev);
10600
10601	dev_net_set(dev, &init_net);
10602
10603	dev->gso_max_size = GSO_LEGACY_MAX_SIZE;
10604	dev->gso_max_segs = GSO_MAX_SEGS;
10605	dev->gro_max_size = GRO_LEGACY_MAX_SIZE;
10606	dev->tso_max_size = TSO_LEGACY_MAX_SIZE;
10607	dev->tso_max_segs = TSO_MAX_SEGS;
10608	dev->upper_level = 1;
10609	dev->lower_level = 1;
10610#ifdef CONFIG_LOCKDEP
10611	dev->nested_level = 0;
10612	INIT_LIST_HEAD(&dev->unlink_list);
10613#endif
10614
10615	INIT_LIST_HEAD(&dev->napi_list);
10616	INIT_LIST_HEAD(&dev->unreg_list);
10617	INIT_LIST_HEAD(&dev->close_list);
10618	INIT_LIST_HEAD(&dev->link_watch_list);
10619	INIT_LIST_HEAD(&dev->adj_list.upper);
10620	INIT_LIST_HEAD(&dev->adj_list.lower);
10621	INIT_LIST_HEAD(&dev->ptype_all);
10622	INIT_LIST_HEAD(&dev->ptype_specific);
10623	INIT_LIST_HEAD(&dev->net_notifier_list);
10624#ifdef CONFIG_NET_SCHED
10625	hash_init(dev->qdisc_hash);
10626#endif
10627	dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
10628	setup(dev);
10629
10630	if (!dev->tx_queue_len) {
10631		dev->priv_flags |= IFF_NO_QUEUE;
10632		dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
10633	}
10634
10635	dev->num_tx_queues = txqs;
10636	dev->real_num_tx_queues = txqs;
10637	if (netif_alloc_netdev_queues(dev))
10638		goto free_all;
10639
 
10640	dev->num_rx_queues = rxqs;
10641	dev->real_num_rx_queues = rxqs;
10642	if (netif_alloc_rx_queues(dev))
10643		goto free_all;
 
10644
10645	strcpy(dev->name, name);
10646	dev->name_assign_type = name_assign_type;
10647	dev->group = INIT_NETDEV_GROUP;
10648	if (!dev->ethtool_ops)
10649		dev->ethtool_ops = &default_ethtool_ops;
10650
10651	nf_hook_netdev_init(dev);
10652
10653	return dev;
10654
10655free_all:
10656	free_netdev(dev);
10657	return NULL;
10658
10659free_pcpu:
10660#ifdef CONFIG_PCPU_DEV_REFCNT
10661	free_percpu(dev->pcpu_refcnt);
10662free_dev:
 
 
10663#endif
10664	netdev_freemem(dev);
 
 
10665	return NULL;
10666}
10667EXPORT_SYMBOL(alloc_netdev_mqs);
10668
10669/**
10670 * free_netdev - free network device
10671 * @dev: device
10672 *
10673 * This function does the last stage of destroying an allocated device
10674 * interface. The reference to the device object is released. If this
10675 * is the last reference then it will be freed.Must be called in process
10676 * context.
10677 */
10678void free_netdev(struct net_device *dev)
10679{
10680	struct napi_struct *p, *n;
10681
10682	might_sleep();
10683
10684	/* When called immediately after register_netdevice() failed the unwind
10685	 * handling may still be dismantling the device. Handle that case by
10686	 * deferring the free.
10687	 */
10688	if (dev->reg_state == NETREG_UNREGISTERING) {
10689		ASSERT_RTNL();
10690		dev->needs_free_netdev = true;
10691		return;
10692	}
10693
10694	netif_free_tx_queues(dev);
10695	netif_free_rx_queues(dev);
 
 
10696
10697	kfree(rcu_dereference_protected(dev->ingress_queue, 1));
10698
10699	/* Flush device addresses */
10700	dev_addr_flush(dev);
10701
10702	list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
10703		netif_napi_del(p);
10704
10705	ref_tracker_dir_exit(&dev->refcnt_tracker);
10706#ifdef CONFIG_PCPU_DEV_REFCNT
10707	free_percpu(dev->pcpu_refcnt);
10708	dev->pcpu_refcnt = NULL;
10709#endif
10710	free_percpu(dev->core_stats);
10711	dev->core_stats = NULL;
10712	free_percpu(dev->xdp_bulkq);
10713	dev->xdp_bulkq = NULL;
10714
10715	/*  Compatibility with error handling in drivers */
10716	if (dev->reg_state == NETREG_UNINITIALIZED) {
10717		netdev_freemem(dev);
10718		return;
10719	}
10720
10721	BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
10722	dev->reg_state = NETREG_RELEASED;
10723
10724	/* will free via device release */
10725	put_device(&dev->dev);
10726}
10727EXPORT_SYMBOL(free_netdev);
10728
10729/**
10730 *	synchronize_net -  Synchronize with packet receive processing
10731 *
10732 *	Wait for packets currently being received to be done.
10733 *	Does not block later packets from starting.
10734 */
10735void synchronize_net(void)
10736{
10737	might_sleep();
10738	if (rtnl_is_locked())
10739		synchronize_rcu_expedited();
10740	else
10741		synchronize_rcu();
10742}
10743EXPORT_SYMBOL(synchronize_net);
10744
10745/**
10746 *	unregister_netdevice_queue - remove device from the kernel
10747 *	@dev: device
10748 *	@head: list
10749 *
10750 *	This function shuts down a device interface and removes it
10751 *	from the kernel tables.
10752 *	If head not NULL, device is queued to be unregistered later.
10753 *
10754 *	Callers must hold the rtnl semaphore.  You may want
10755 *	unregister_netdev() instead of this.
10756 */
10757
10758void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
10759{
10760	ASSERT_RTNL();
10761
10762	if (head) {
10763		list_move_tail(&dev->unreg_list, head);
10764	} else {
10765		LIST_HEAD(single);
10766
10767		list_add(&dev->unreg_list, &single);
10768		unregister_netdevice_many(&single);
10769	}
10770}
10771EXPORT_SYMBOL(unregister_netdevice_queue);
10772
10773void unregister_netdevice_many_notify(struct list_head *head,
10774				      u32 portid, const struct nlmsghdr *nlh)
10775{
10776	struct net_device *dev, *tmp;
10777	LIST_HEAD(close_head);
10778
10779	BUG_ON(dev_boot_phase);
10780	ASSERT_RTNL();
10781
10782	if (list_empty(head))
10783		return;
10784
10785	list_for_each_entry_safe(dev, tmp, head, unreg_list) {
10786		/* Some devices call without registering
10787		 * for initialization unwind. Remove those
10788		 * devices and proceed with the remaining.
10789		 */
10790		if (dev->reg_state == NETREG_UNINITIALIZED) {
10791			pr_debug("unregister_netdevice: device %s/%p never was registered\n",
10792				 dev->name, dev);
10793
10794			WARN_ON(1);
10795			list_del(&dev->unreg_list);
10796			continue;
10797		}
10798		dev->dismantle = true;
10799		BUG_ON(dev->reg_state != NETREG_REGISTERED);
10800	}
10801
10802	/* If device is running, close it first. */
10803	list_for_each_entry(dev, head, unreg_list)
10804		list_add_tail(&dev->close_list, &close_head);
10805	dev_close_many(&close_head, true);
10806
10807	list_for_each_entry(dev, head, unreg_list) {
10808		/* And unlink it from device chain. */
10809		write_lock(&dev_base_lock);
10810		unlist_netdevice(dev, false);
10811		dev->reg_state = NETREG_UNREGISTERING;
10812		write_unlock(&dev_base_lock);
10813	}
10814	flush_all_backlogs();
10815
10816	synchronize_net();
10817
10818	list_for_each_entry(dev, head, unreg_list) {
10819		struct sk_buff *skb = NULL;
10820
10821		/* Shutdown queueing discipline. */
10822		dev_shutdown(dev);
10823
10824		dev_xdp_uninstall(dev);
10825
10826		netdev_offload_xstats_disable_all(dev);
10827
10828		/* Notify protocols, that we are about to destroy
10829		 * this device. They should clean all the things.
10830		 */
10831		call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
10832
10833		if (!dev->rtnl_link_ops ||
10834		    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
10835			skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U, 0,
10836						     GFP_KERNEL, NULL, 0,
10837						     portid, nlmsg_seq(nlh));
10838
10839		/*
10840		 *	Flush the unicast and multicast chains
10841		 */
10842		dev_uc_flush(dev);
10843		dev_mc_flush(dev);
10844
10845		netdev_name_node_alt_flush(dev);
10846		netdev_name_node_free(dev->name_node);
10847
10848		call_netdevice_notifiers(NETDEV_PRE_UNINIT, dev);
10849
10850		if (dev->netdev_ops->ndo_uninit)
10851			dev->netdev_ops->ndo_uninit(dev);
10852
10853		if (skb)
10854			rtmsg_ifinfo_send(skb, dev, GFP_KERNEL, portid, nlh);
10855
10856		/* Notifier chain MUST detach us all upper devices. */
10857		WARN_ON(netdev_has_any_upper_dev(dev));
10858		WARN_ON(netdev_has_any_lower_dev(dev));
10859
10860		/* Remove entries from kobject tree */
10861		netdev_unregister_kobject(dev);
10862#ifdef CONFIG_XPS
10863		/* Remove XPS queueing entries */
10864		netif_reset_xps_queues_gt(dev, 0);
10865#endif
10866	}
10867
10868	synchronize_net();
10869
10870	list_for_each_entry(dev, head, unreg_list) {
10871		netdev_put(dev, &dev->dev_registered_tracker);
10872		net_set_todo(dev);
10873	}
10874
10875	list_del(head);
10876}
 
10877
10878/**
10879 *	unregister_netdevice_many - unregister many devices
10880 *	@head: list of devices
10881 *
10882 *  Note: As most callers use a stack allocated list_head,
10883 *  we force a list_del() to make sure stack wont be corrupted later.
10884 */
10885void unregister_netdevice_many(struct list_head *head)
10886{
10887	unregister_netdevice_many_notify(head, 0, NULL);
 
 
 
 
 
 
10888}
10889EXPORT_SYMBOL(unregister_netdevice_many);
10890
10891/**
10892 *	unregister_netdev - remove device from the kernel
10893 *	@dev: device
10894 *
10895 *	This function shuts down a device interface and removes it
10896 *	from the kernel tables.
10897 *
10898 *	This is just a wrapper for unregister_netdevice that takes
10899 *	the rtnl semaphore.  In general you want to use this and not
10900 *	unregister_netdevice.
10901 */
10902void unregister_netdev(struct net_device *dev)
10903{
10904	rtnl_lock();
10905	unregister_netdevice(dev);
10906	rtnl_unlock();
10907}
10908EXPORT_SYMBOL(unregister_netdev);
10909
10910/**
10911 *	__dev_change_net_namespace - move device to different nethost namespace
10912 *	@dev: device
10913 *	@net: network namespace
10914 *	@pat: If not NULL name pattern to try if the current device name
10915 *	      is already taken in the destination network namespace.
10916 *	@new_ifindex: If not zero, specifies device index in the target
10917 *	              namespace.
10918 *
10919 *	This function shuts down a device interface and moves it
10920 *	to a new network namespace. On success 0 is returned, on
10921 *	a failure a netagive errno code is returned.
10922 *
10923 *	Callers must hold the rtnl semaphore.
10924 */
10925
10926int __dev_change_net_namespace(struct net_device *dev, struct net *net,
10927			       const char *pat, int new_ifindex)
10928{
10929	struct net *net_old = dev_net(dev);
10930	int err, new_nsid;
10931
10932	ASSERT_RTNL();
10933
10934	/* Don't allow namespace local devices to be moved. */
10935	err = -EINVAL;
10936	if (dev->features & NETIF_F_NETNS_LOCAL)
10937		goto out;
10938
10939	/* Ensure the device has been registrered */
 
10940	if (dev->reg_state != NETREG_REGISTERED)
10941		goto out;
10942
10943	/* Get out if there is nothing todo */
10944	err = 0;
10945	if (net_eq(net_old, net))
10946		goto out;
10947
10948	/* Pick the destination device name, and ensure
10949	 * we can use it in the destination network namespace.
10950	 */
10951	err = -EEXIST;
10952	if (netdev_name_in_use(net, dev->name)) {
10953		/* We get here if we can't use the current device name */
10954		if (!pat)
10955			goto out;
10956		err = dev_get_valid_name(net, dev, pat);
10957		if (err < 0)
10958			goto out;
10959	}
10960
10961	/* Check that new_ifindex isn't used yet. */
10962	err = -EBUSY;
10963	if (new_ifindex && __dev_get_by_index(net, new_ifindex))
10964		goto out;
10965
10966	/*
10967	 * And now a mini version of register_netdevice unregister_netdevice.
10968	 */
10969
10970	/* If device is running close it first. */
10971	dev_close(dev);
10972
10973	/* And unlink it from device chain */
10974	unlist_netdevice(dev, true);
 
10975
10976	synchronize_net();
10977
10978	/* Shutdown queueing discipline. */
10979	dev_shutdown(dev);
10980
10981	/* Notify protocols, that we are about to destroy
10982	 * this device. They should clean all the things.
10983	 *
10984	 * Note that dev->reg_state stays at NETREG_REGISTERED.
10985	 * This is wanted because this way 8021q and macvlan know
10986	 * the device is just moving and can keep their slaves up.
10987	 */
10988	call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
10989	rcu_barrier();
10990
10991	new_nsid = peernet2id_alloc(dev_net(dev), net, GFP_KERNEL);
10992	/* If there is an ifindex conflict assign a new one */
10993	if (!new_ifindex) {
10994		if (__dev_get_by_index(net, dev->ifindex))
10995			new_ifindex = dev_new_index(net);
10996		else
10997			new_ifindex = dev->ifindex;
10998	}
10999
11000	rtmsg_ifinfo_newnet(RTM_DELLINK, dev, ~0U, GFP_KERNEL, &new_nsid,
11001			    new_ifindex);
 
 
 
 
11002
11003	/*
11004	 *	Flush the unicast and multicast chains
11005	 */
11006	dev_uc_flush(dev);
11007	dev_mc_flush(dev);
11008
11009	/* Send a netdev-removed uevent to the old namespace */
11010	kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
11011	netdev_adjacent_del_links(dev);
11012
11013	/* Move per-net netdevice notifiers that are following the netdevice */
11014	move_netdevice_notifiers_dev_net(dev, net);
11015
11016	/* Actually switch the network namespace */
11017	dev_net_set(dev, net);
11018	dev->ifindex = new_ifindex;
11019
11020	/* Send a netdev-add uevent to the new namespace */
11021	kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
11022	netdev_adjacent_add_links(dev);
 
 
 
 
11023
11024	/* Fixup kobjects */
11025	err = device_rename(&dev->dev, dev->name);
11026	WARN_ON(err);
11027
11028	/* Adapt owner in case owning user namespace of target network
11029	 * namespace is different from the original one.
11030	 */
11031	err = netdev_change_owner(dev, net_old, net);
11032	WARN_ON(err);
11033
11034	/* Add the device back in the hashes */
11035	list_netdevice(dev);
11036
11037	/* Notify protocols, that a new device appeared. */
11038	call_netdevice_notifiers(NETDEV_REGISTER, dev);
11039
11040	/*
11041	 *	Prevent userspace races by waiting until the network
11042	 *	device is fully setup before sending notifications.
11043	 */
11044	rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL, 0, NULL);
11045
11046	synchronize_net();
11047	err = 0;
11048out:
11049	return err;
11050}
11051EXPORT_SYMBOL_GPL(__dev_change_net_namespace);
11052
11053static int dev_cpu_dead(unsigned int oldcpu)
 
 
11054{
11055	struct sk_buff **list_skb;
11056	struct sk_buff *skb;
11057	unsigned int cpu;
11058	struct softnet_data *sd, *oldsd, *remsd = NULL;
 
 
 
11059
11060	local_irq_disable();
11061	cpu = smp_processor_id();
11062	sd = &per_cpu(softnet_data, cpu);
11063	oldsd = &per_cpu(softnet_data, oldcpu);
11064
11065	/* Find end of our completion_queue. */
11066	list_skb = &sd->completion_queue;
11067	while (*list_skb)
11068		list_skb = &(*list_skb)->next;
11069	/* Append completion queue from offline CPU. */
11070	*list_skb = oldsd->completion_queue;
11071	oldsd->completion_queue = NULL;
11072
11073	/* Append output queue from offline CPU. */
11074	if (oldsd->output_queue) {
11075		*sd->output_queue_tailp = oldsd->output_queue;
11076		sd->output_queue_tailp = oldsd->output_queue_tailp;
11077		oldsd->output_queue = NULL;
11078		oldsd->output_queue_tailp = &oldsd->output_queue;
11079	}
11080	/* Append NAPI poll list from offline CPU, with one exception :
11081	 * process_backlog() must be called by cpu owning percpu backlog.
11082	 * We properly handle process_queue & input_pkt_queue later.
11083	 */
11084	while (!list_empty(&oldsd->poll_list)) {
11085		struct napi_struct *napi = list_first_entry(&oldsd->poll_list,
11086							    struct napi_struct,
11087							    poll_list);
11088
11089		list_del_init(&napi->poll_list);
11090		if (napi->poll == process_backlog)
11091			napi->state = 0;
11092		else
11093			____napi_schedule(sd, napi);
11094	}
11095
11096	raise_softirq_irqoff(NET_TX_SOFTIRQ);
11097	local_irq_enable();
11098
11099#ifdef CONFIG_RPS
11100	remsd = oldsd->rps_ipi_list;
11101	oldsd->rps_ipi_list = NULL;
11102#endif
11103	/* send out pending IPI's on offline CPU */
11104	net_rps_send_ipi(remsd);
11105
11106	/* Process offline CPU's input_pkt_queue */
11107	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
11108		netif_rx(skb);
11109		input_queue_head_incr(oldsd);
11110	}
11111	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
11112		netif_rx(skb);
11113		input_queue_head_incr(oldsd);
11114	}
11115
11116	return 0;
11117}
11118
 
11119/**
11120 *	netdev_increment_features - increment feature set by one
11121 *	@all: current feature set
11122 *	@one: new feature set
11123 *	@mask: mask feature set
11124 *
11125 *	Computes a new feature set after adding a device with feature set
11126 *	@one to the master device with current feature set @all.  Will not
11127 *	enable anything that is off in @mask. Returns the new feature set.
11128 */
11129netdev_features_t netdev_increment_features(netdev_features_t all,
11130	netdev_features_t one, netdev_features_t mask)
11131{
11132	if (mask & NETIF_F_HW_CSUM)
11133		mask |= NETIF_F_CSUM_MASK;
11134	mask |= NETIF_F_VLAN_CHALLENGED;
11135
11136	all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask;
11137	all &= one | ~NETIF_F_ALL_FOR_ALL;
11138
 
 
 
 
11139	/* If one device supports hw checksumming, set for all. */
11140	if (all & NETIF_F_HW_CSUM)
11141		all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM);
11142
11143	return all;
11144}
11145EXPORT_SYMBOL(netdev_increment_features);
11146
11147static struct hlist_head * __net_init netdev_create_hash(void)
11148{
11149	int i;
11150	struct hlist_head *hash;
11151
11152	hash = kmalloc_array(NETDEV_HASHENTRIES, sizeof(*hash), GFP_KERNEL);
11153	if (hash != NULL)
11154		for (i = 0; i < NETDEV_HASHENTRIES; i++)
11155			INIT_HLIST_HEAD(&hash[i]);
11156
11157	return hash;
11158}
11159
11160/* Initialize per network namespace state */
11161static int __net_init netdev_init(struct net *net)
11162{
11163	BUILD_BUG_ON(GRO_HASH_BUCKETS >
11164		     8 * sizeof_field(struct napi_struct, gro_bitmask));
11165
11166	INIT_LIST_HEAD(&net->dev_base_head);
11167
11168	net->dev_name_head = netdev_create_hash();
11169	if (net->dev_name_head == NULL)
11170		goto err_name;
11171
11172	net->dev_index_head = netdev_create_hash();
11173	if (net->dev_index_head == NULL)
11174		goto err_idx;
11175
11176	RAW_INIT_NOTIFIER_HEAD(&net->netdev_chain);
11177
11178	return 0;
11179
11180err_idx:
11181	kfree(net->dev_name_head);
11182err_name:
11183	return -ENOMEM;
11184}
11185
11186/**
11187 *	netdev_drivername - network driver for the device
11188 *	@dev: network device
11189 *
11190 *	Determine network driver for device.
11191 */
11192const char *netdev_drivername(const struct net_device *dev)
11193{
11194	const struct device_driver *driver;
11195	const struct device *parent;
11196	const char *empty = "";
11197
11198	parent = dev->dev.parent;
11199	if (!parent)
11200		return empty;
11201
11202	driver = parent->driver;
11203	if (driver && driver->name)
11204		return driver->name;
11205	return empty;
11206}
11207
11208static void __netdev_printk(const char *level, const struct net_device *dev,
11209			    struct va_format *vaf)
11210{
11211	if (dev && dev->dev.parent) {
11212		dev_printk_emit(level[1] - '0',
11213				dev->dev.parent,
11214				"%s %s %s%s: %pV",
11215				dev_driver_string(dev->dev.parent),
11216				dev_name(dev->dev.parent),
11217				netdev_name(dev), netdev_reg_state(dev),
11218				vaf);
11219	} else if (dev) {
11220		printk("%s%s%s: %pV",
11221		       level, netdev_name(dev), netdev_reg_state(dev), vaf);
11222	} else {
11223		printk("%s(NULL net_device): %pV", level, vaf);
11224	}
11225}
11226
11227void netdev_printk(const char *level, const struct net_device *dev,
11228		   const char *format, ...)
11229{
11230	struct va_format vaf;
11231	va_list args;
 
11232
11233	va_start(args, format);
11234
11235	vaf.fmt = format;
11236	vaf.va = &args;
11237
11238	__netdev_printk(level, dev, &vaf);
11239
11240	va_end(args);
 
 
11241}
11242EXPORT_SYMBOL(netdev_printk);
11243
11244#define define_netdev_printk_level(func, level)			\
11245void func(const struct net_device *dev, const char *fmt, ...)	\
11246{								\
 
11247	struct va_format vaf;					\
11248	va_list args;						\
11249								\
11250	va_start(args, fmt);					\
11251								\
11252	vaf.fmt = fmt;						\
11253	vaf.va = &args;						\
11254								\
11255	__netdev_printk(level, dev, &vaf);			\
11256								\
11257	va_end(args);						\
 
 
11258}								\
11259EXPORT_SYMBOL(func);
11260
11261define_netdev_printk_level(netdev_emerg, KERN_EMERG);
11262define_netdev_printk_level(netdev_alert, KERN_ALERT);
11263define_netdev_printk_level(netdev_crit, KERN_CRIT);
11264define_netdev_printk_level(netdev_err, KERN_ERR);
11265define_netdev_printk_level(netdev_warn, KERN_WARNING);
11266define_netdev_printk_level(netdev_notice, KERN_NOTICE);
11267define_netdev_printk_level(netdev_info, KERN_INFO);
11268
11269static void __net_exit netdev_exit(struct net *net)
11270{
11271	kfree(net->dev_name_head);
11272	kfree(net->dev_index_head);
11273	if (net != &init_net)
11274		WARN_ON_ONCE(!list_empty(&net->dev_base_head));
11275}
11276
11277static struct pernet_operations __net_initdata netdev_net_ops = {
11278	.init = netdev_init,
11279	.exit = netdev_exit,
11280};
11281
11282static void __net_exit default_device_exit_net(struct net *net)
11283{
11284	struct net_device *dev, *aux;
11285	/*
11286	 * Push all migratable network devices back to the
11287	 * initial network namespace
11288	 */
11289	ASSERT_RTNL();
11290	for_each_netdev_safe(net, dev, aux) {
11291		int err;
11292		char fb_name[IFNAMSIZ];
11293
11294		/* Ignore unmoveable devices (i.e. loopback) */
11295		if (dev->features & NETIF_F_NETNS_LOCAL)
11296			continue;
11297
11298		/* Leave virtual devices for the generic cleanup */
11299		if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund)
11300			continue;
11301
11302		/* Push remaining network devices to init_net */
11303		snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
11304		if (netdev_name_in_use(&init_net, fb_name))
11305			snprintf(fb_name, IFNAMSIZ, "dev%%d");
11306		err = dev_change_net_namespace(dev, &init_net, fb_name);
11307		if (err) {
11308			pr_emerg("%s: failed to move %s to init_net: %d\n",
11309				 __func__, dev->name, err);
11310			BUG();
11311		}
11312	}
 
11313}
11314
11315static void __net_exit default_device_exit_batch(struct list_head *net_list)
11316{
11317	/* At exit all network devices most be removed from a network
11318	 * namespace.  Do this in the reverse order of registration.
11319	 * Do this across as many network namespaces as possible to
11320	 * improve batching efficiency.
11321	 */
11322	struct net_device *dev;
11323	struct net *net;
11324	LIST_HEAD(dev_kill_list);
11325
11326	rtnl_lock();
11327	list_for_each_entry(net, net_list, exit_list) {
11328		default_device_exit_net(net);
11329		cond_resched();
11330	}
11331
11332	list_for_each_entry(net, net_list, exit_list) {
11333		for_each_netdev_reverse(net, dev) {
11334			if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
11335				dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
11336			else
11337				unregister_netdevice_queue(dev, &dev_kill_list);
11338		}
11339	}
11340	unregister_netdevice_many(&dev_kill_list);
 
11341	rtnl_unlock();
11342}
11343
11344static struct pernet_operations __net_initdata default_device_ops = {
 
11345	.exit_batch = default_device_exit_batch,
11346};
11347
11348/*
11349 *	Initialize the DEV module. At boot time this walks the device list and
11350 *	unhooks any devices that fail to initialise (normally hardware not
11351 *	present) and leaves us with a valid list of present and active devices.
11352 *
11353 */
11354
11355/*
11356 *       This is called single threaded during boot, so no need
11357 *       to take the rtnl semaphore.
11358 */
11359static int __init net_dev_init(void)
11360{
11361	int i, rc = -ENOMEM;
11362
11363	BUG_ON(!dev_boot_phase);
11364
11365	if (dev_proc_init())
11366		goto out;
11367
11368	if (netdev_kobject_init())
11369		goto out;
11370
11371	INIT_LIST_HEAD(&ptype_all);
11372	for (i = 0; i < PTYPE_HASH_SIZE; i++)
11373		INIT_LIST_HEAD(&ptype_base[i]);
11374
11375	if (register_pernet_subsys(&netdev_net_ops))
11376		goto out;
11377
11378	/*
11379	 *	Initialise the packet receive queues.
11380	 */
11381
11382	for_each_possible_cpu(i) {
11383		struct work_struct *flush = per_cpu_ptr(&flush_works, i);
11384		struct softnet_data *sd = &per_cpu(softnet_data, i);
11385
11386		INIT_WORK(flush, flush_backlog);
11387
11388		skb_queue_head_init(&sd->input_pkt_queue);
11389		skb_queue_head_init(&sd->process_queue);
11390#ifdef CONFIG_XFRM_OFFLOAD
11391		skb_queue_head_init(&sd->xfrm_backlog);
11392#endif
11393		INIT_LIST_HEAD(&sd->poll_list);
 
11394		sd->output_queue_tailp = &sd->output_queue;
11395#ifdef CONFIG_RPS
11396		INIT_CSD(&sd->csd, rps_trigger_softirq, sd);
 
 
11397		sd->cpu = i;
11398#endif
11399		INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd);
11400		spin_lock_init(&sd->defer_lock);
11401
11402		init_gro_hash(&sd->backlog);
11403		sd->backlog.poll = process_backlog;
11404		sd->backlog.weight = weight_p;
 
 
11405	}
11406
11407	dev_boot_phase = 0;
11408
11409	/* The loopback device is special if any other network devices
11410	 * is present in a network namespace the loopback device must
11411	 * be present. Since we now dynamically allocate and free the
11412	 * loopback device ensure this invariant is maintained by
11413	 * keeping the loopback device as the first device on the
11414	 * list of network devices.  Ensuring the loopback devices
11415	 * is the first device that appears and the last network device
11416	 * that disappears.
11417	 */
11418	if (register_pernet_device(&loopback_net_ops))
11419		goto out;
11420
11421	if (register_pernet_device(&default_device_ops))
11422		goto out;
11423
11424	open_softirq(NET_TX_SOFTIRQ, net_tx_action);
11425	open_softirq(NET_RX_SOFTIRQ, net_rx_action);
11426
11427	rc = cpuhp_setup_state_nocalls(CPUHP_NET_DEV_DEAD, "net/dev:dead",
11428				       NULL, dev_cpu_dead);
11429	WARN_ON(rc < 0);
11430	rc = 0;
11431out:
11432	return rc;
11433}
11434
11435subsys_initcall(net_dev_init);