1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * net-sysfs.c - network device class and attributes
   4 *
   5 * Copyright (c) 2003 Stephen Hemminger <shemminger@osdl.org>
 
 
 
 
 
   6 */
   7
   8#include <linux/capability.h>
   9#include <linux/kernel.h>
  10#include <linux/netdevice.h>
  11#include <linux/if_arp.h>
  12#include <linux/slab.h>
  13#include <linux/sched/signal.h>
  14#include <linux/sched/isolation.h>
  15#include <linux/nsproxy.h>
  16#include <net/sock.h>
  17#include <net/net_namespace.h>
  18#include <linux/rtnetlink.h>
 
  19#include <linux/vmalloc.h>
  20#include <linux/export.h>
  21#include <linux/jiffies.h>
  22#include <linux/pm_runtime.h>
  23#include <linux/of.h>
  24#include <linux/of_net.h>
  25#include <linux/cpu.h>
  26#include <net/netdev_rx_queue.h>
  27#include <net/rps.h>
  28
  29#include "dev.h"
  30#include "net-sysfs.h"
  31
  32#ifdef CONFIG_SYSFS
  33static const char fmt_hex[] = "%#x\n";
 
  34static const char fmt_dec[] = "%d\n";
  35static const char fmt_uint[] = "%u\n";
  36static const char fmt_ulong[] = "%lu\n";
  37static const char fmt_u64[] = "%llu\n";
  38
  39/* Caller holds RTNL or RCU */
  40static inline int dev_isalive(const struct net_device *dev)
  41{
  42	return READ_ONCE(dev->reg_state) <= NETREG_REGISTERED;
  43}
  44
  45/* use same locking rules as GIF* ioctl's */
  46static ssize_t netdev_show(const struct device *dev,
  47			   struct device_attribute *attr, char *buf,
  48			   ssize_t (*format)(const struct net_device *, char *))
  49{
  50	struct net_device *ndev = to_net_dev(dev);
  51	ssize_t ret = -EINVAL;
  52
  53	rcu_read_lock();
  54	if (dev_isalive(ndev))
  55		ret = (*format)(ndev, buf);
  56	rcu_read_unlock();
  57
  58	return ret;
  59}
  60
  61/* generate a show function for simple field */
  62#define NETDEVICE_SHOW(field, format_string)				\
  63static ssize_t format_##field(const struct net_device *dev, char *buf)	\
  64{									\
  65	return sysfs_emit(buf, format_string, READ_ONCE(dev->field));		\
  66}									\
  67static ssize_t field##_show(struct device *dev,				\
  68			    struct device_attribute *attr, char *buf)	\
  69{									\
  70	return netdev_show(dev, attr, buf, format_##field);		\
  71}									\
  72
  73#define NETDEVICE_SHOW_RO(field, format_string)				\
  74NETDEVICE_SHOW(field, format_string);					\
  75static DEVICE_ATTR_RO(field)
  76
  77#define NETDEVICE_SHOW_RW(field, format_string)				\
  78NETDEVICE_SHOW(field, format_string);					\
  79static DEVICE_ATTR_RW(field)
  80
  81/* use same locking and permission rules as SIF* ioctl's */
  82static ssize_t netdev_store(struct device *dev, struct device_attribute *attr,
  83			    const char *buf, size_t len,
  84			    int (*set)(struct net_device *, unsigned long))
  85{
  86	struct net_device *netdev = to_net_dev(dev);
  87	struct net *net = dev_net(netdev);
  88	unsigned long new;
  89	int ret;
  90
  91	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
  92		return -EPERM;
  93
  94	ret = kstrtoul(buf, 0, &new);
  95	if (ret)
  96		goto err;
  97
  98	if (!rtnl_trylock())
  99		return restart_syscall();
 100
 101	if (dev_isalive(netdev)) {
 102		ret = (*set)(netdev, new);
 103		if (ret == 0)
 104			ret = len;
 105	}
 106	rtnl_unlock();
 107 err:
 108	return ret;
 109}
 110
 111NETDEVICE_SHOW_RO(dev_id, fmt_hex);
 112NETDEVICE_SHOW_RO(dev_port, fmt_dec);
 113NETDEVICE_SHOW_RO(addr_assign_type, fmt_dec);
 114NETDEVICE_SHOW_RO(addr_len, fmt_dec);
 115NETDEVICE_SHOW_RO(ifindex, fmt_dec);
 116NETDEVICE_SHOW_RO(type, fmt_dec);
 117NETDEVICE_SHOW_RO(link_mode, fmt_dec);
 118
 119static ssize_t iflink_show(struct device *dev, struct device_attribute *attr,
 120			   char *buf)
 121{
 122	struct net_device *ndev = to_net_dev(dev);
 123
 124	return sysfs_emit(buf, fmt_dec, dev_get_iflink(ndev));
 125}
 126static DEVICE_ATTR_RO(iflink);
 127
 128static ssize_t format_name_assign_type(const struct net_device *dev, char *buf)
 129{
 130	return sysfs_emit(buf, fmt_dec, READ_ONCE(dev->name_assign_type));
 131}
 132
 133static ssize_t name_assign_type_show(struct device *dev,
 134				     struct device_attribute *attr,
 135				     char *buf)
 136{
 137	struct net_device *ndev = to_net_dev(dev);
 138	ssize_t ret = -EINVAL;
 139
 140	if (READ_ONCE(ndev->name_assign_type) != NET_NAME_UNKNOWN)
 141		ret = netdev_show(dev, attr, buf, format_name_assign_type);
 142
 143	return ret;
 144}
 145static DEVICE_ATTR_RO(name_assign_type);
 146
 147/* use same locking rules as GIFHWADDR ioctl's (dev_get_mac_address()) */
 148static ssize_t address_show(struct device *dev, struct device_attribute *attr,
 149			    char *buf)
 150{
 151	struct net_device *ndev = to_net_dev(dev);
 152	ssize_t ret = -EINVAL;
 153
 154	down_read(&dev_addr_sem);
 155
 156	rcu_read_lock();
 157	if (dev_isalive(ndev))
 158		ret = sysfs_format_mac(buf, ndev->dev_addr, ndev->addr_len);
 159	rcu_read_unlock();
 160
 161	up_read(&dev_addr_sem);
 162	return ret;
 163}
 164static DEVICE_ATTR_RO(address);
 165
 166static ssize_t broadcast_show(struct device *dev,
 167			      struct device_attribute *attr, char *buf)
 168{
 169	struct net_device *ndev = to_net_dev(dev);
 170	int ret = -EINVAL;
 171
 172	rcu_read_lock();
 173	if (dev_isalive(ndev))
 174		ret = sysfs_format_mac(buf, ndev->broadcast, ndev->addr_len);
 175	rcu_read_unlock();
 176	return ret;
 177}
 178static DEVICE_ATTR_RO(broadcast);
 179
 180static int change_carrier(struct net_device *dev, unsigned long new_carrier)
 181{
 182	if (!netif_running(dev))
 183		return -EINVAL;
 184	return dev_change_carrier(dev, (bool)new_carrier);
 185}
 186
 187static ssize_t carrier_store(struct device *dev, struct device_attribute *attr,
 188			     const char *buf, size_t len)
 189{
 190	struct net_device *netdev = to_net_dev(dev);
 191
 192	/* The check is also done in change_carrier; this helps returning early
 193	 * without hitting the trylock/restart in netdev_store.
 194	 */
 195	if (!netdev->netdev_ops->ndo_change_carrier)
 196		return -EOPNOTSUPP;
 197
 198	return netdev_store(dev, attr, buf, len, change_carrier);
 199}
 200
 201static ssize_t carrier_show(struct device *dev,
 202			    struct device_attribute *attr, char *buf)
 203{
 204	struct net_device *netdev = to_net_dev(dev);
 205	int ret = -EINVAL;
 206
 207	if (!rtnl_trylock())
 208		return restart_syscall();
 209
 210	if (netif_running(netdev)) {
 211		/* Synchronize carrier state with link watch,
 212		 * see also rtnl_getlink().
 213		 */
 214		linkwatch_sync_dev(netdev);
 215
 216		ret = sysfs_emit(buf, fmt_dec, !!netif_carrier_ok(netdev));
 217	}
 218	rtnl_unlock();
 219
 220	return ret;
 221}
 222static DEVICE_ATTR_RW(carrier);
 223
 224static ssize_t speed_show(struct device *dev,
 225			  struct device_attribute *attr, char *buf)
 226{
 227	struct net_device *netdev = to_net_dev(dev);
 228	int ret = -EINVAL;
 229
 230	/* The check is also done in __ethtool_get_link_ksettings; this helps
 231	 * returning early without hitting the trylock/restart below.
 232	 */
 233	if (!netdev->ethtool_ops->get_link_ksettings)
 234		return ret;
 235
 236	if (!rtnl_trylock())
 237		return restart_syscall();
 238
 239	if (netif_running(netdev)) {
 240		struct ethtool_link_ksettings cmd;
 241
 242		if (!__ethtool_get_link_ksettings(netdev, &cmd))
 243			ret = sysfs_emit(buf, fmt_dec, cmd.base.speed);
 244	}
 245	rtnl_unlock();
 246	return ret;
 247}
 248static DEVICE_ATTR_RO(speed);
 249
 250static ssize_t duplex_show(struct device *dev,
 251			   struct device_attribute *attr, char *buf)
 252{
 253	struct net_device *netdev = to_net_dev(dev);
 254	int ret = -EINVAL;
 255
 256	/* The check is also done in __ethtool_get_link_ksettings; this helps
 257	 * returning early without hitting the trylock/restart below.
 258	 */
 259	if (!netdev->ethtool_ops->get_link_ksettings)
 260		return ret;
 261
 262	if (!rtnl_trylock())
 263		return restart_syscall();
 264
 265	if (netif_running(netdev)) {
 266		struct ethtool_link_ksettings cmd;
 267
 268		if (!__ethtool_get_link_ksettings(netdev, &cmd)) {
 269			const char *duplex;
 270
 271			switch (cmd.base.duplex) {
 272			case DUPLEX_HALF:
 273				duplex = "half";
 274				break;
 275			case DUPLEX_FULL:
 276				duplex = "full";
 277				break;
 278			default:
 279				duplex = "unknown";
 280				break;
 281			}
 282			ret = sysfs_emit(buf, "%s\n", duplex);
 283		}
 284	}
 285	rtnl_unlock();
 286	return ret;
 287}
 288static DEVICE_ATTR_RO(duplex);
 289
 290static ssize_t testing_show(struct device *dev,
 291			    struct device_attribute *attr, char *buf)
 292{
 293	struct net_device *netdev = to_net_dev(dev);
 294
 295	if (netif_running(netdev))
 296		return sysfs_emit(buf, fmt_dec, !!netif_testing(netdev));
 297
 298	return -EINVAL;
 299}
 300static DEVICE_ATTR_RO(testing);
 301
 302static ssize_t dormant_show(struct device *dev,
 303			    struct device_attribute *attr, char *buf)
 304{
 305	struct net_device *netdev = to_net_dev(dev);
 306
 307	if (netif_running(netdev))
 308		return sysfs_emit(buf, fmt_dec, !!netif_dormant(netdev));
 309
 310	return -EINVAL;
 311}
 312static DEVICE_ATTR_RO(dormant);
 313
 314static const char *const operstates[] = {
 315	"unknown",
 316	"notpresent", /* currently unused */
 317	"down",
 318	"lowerlayerdown",
 319	"testing",
 320	"dormant",
 321	"up"
 322};
 323
 324static ssize_t operstate_show(struct device *dev,
 325			      struct device_attribute *attr, char *buf)
 326{
 327	const struct net_device *netdev = to_net_dev(dev);
 328	unsigned char operstate;
 329
 330	operstate = READ_ONCE(netdev->operstate);
 
 331	if (!netif_running(netdev))
 332		operstate = IF_OPER_DOWN;
 
 333
 334	if (operstate >= ARRAY_SIZE(operstates))
 335		return -EINVAL; /* should not happen */
 336
 337	return sysfs_emit(buf, "%s\n", operstates[operstate]);
 338}
 339static DEVICE_ATTR_RO(operstate);
 340
 341static ssize_t carrier_changes_show(struct device *dev,
 342				    struct device_attribute *attr,
 343				    char *buf)
 344{
 345	struct net_device *netdev = to_net_dev(dev);
 346
 347	return sysfs_emit(buf, fmt_dec,
 348			  atomic_read(&netdev->carrier_up_count) +
 349			  atomic_read(&netdev->carrier_down_count));
 350}
 351static DEVICE_ATTR_RO(carrier_changes);
 352
 353static ssize_t carrier_up_count_show(struct device *dev,
 354				     struct device_attribute *attr,
 355				     char *buf)
 356{
 357	struct net_device *netdev = to_net_dev(dev);
 358
 359	return sysfs_emit(buf, fmt_dec, atomic_read(&netdev->carrier_up_count));
 360}
 361static DEVICE_ATTR_RO(carrier_up_count);
 362
 363static ssize_t carrier_down_count_show(struct device *dev,
 364				       struct device_attribute *attr,
 365				       char *buf)
 366{
 367	struct net_device *netdev = to_net_dev(dev);
 368
 369	return sysfs_emit(buf, fmt_dec, atomic_read(&netdev->carrier_down_count));
 370}
 371static DEVICE_ATTR_RO(carrier_down_count);
 372
 373/* read-write attributes */
 
 374
 375static int change_mtu(struct net_device *dev, unsigned long new_mtu)
 376{
 377	return dev_set_mtu(dev, (int)new_mtu);
 378}
 379
 380static ssize_t mtu_store(struct device *dev, struct device_attribute *attr,
 381			 const char *buf, size_t len)
 382{
 383	return netdev_store(dev, attr, buf, len, change_mtu);
 384}
 385NETDEVICE_SHOW_RW(mtu, fmt_dec);
 386
 387static int change_flags(struct net_device *dev, unsigned long new_flags)
 
 
 388{
 389	return dev_change_flags(dev, (unsigned int)new_flags, NULL);
 390}
 391
 392static ssize_t flags_store(struct device *dev, struct device_attribute *attr,
 393			   const char *buf, size_t len)
 394{
 395	return netdev_store(dev, attr, buf, len, change_flags);
 396}
 397NETDEVICE_SHOW_RW(flags, fmt_hex);
 398
 399static ssize_t tx_queue_len_store(struct device *dev,
 400				  struct device_attribute *attr,
 401				  const char *buf, size_t len)
 402{
 403	if (!capable(CAP_NET_ADMIN))
 404		return -EPERM;
 405
 406	return netdev_store(dev, attr, buf, len, dev_change_tx_queue_len);
 407}
 408NETDEVICE_SHOW_RW(tx_queue_len, fmt_dec);
 409
 410static int change_gro_flush_timeout(struct net_device *dev, unsigned long val)
 411{
 412	netdev_set_gro_flush_timeout(dev, val);
 413	return 0;
 414}
 415
 416static ssize_t gro_flush_timeout_store(struct device *dev,
 417				       struct device_attribute *attr,
 418				       const char *buf, size_t len)
 419{
 420	if (!capable(CAP_NET_ADMIN))
 421		return -EPERM;
 422
 423	return netdev_store(dev, attr, buf, len, change_gro_flush_timeout);
 424}
 425NETDEVICE_SHOW_RW(gro_flush_timeout, fmt_ulong);
 426
 427static int change_napi_defer_hard_irqs(struct net_device *dev, unsigned long val)
 428{
 429	if (val > S32_MAX)
 430		return -ERANGE;
 431
 432	netdev_set_defer_hard_irqs(dev, (u32)val);
 433	return 0;
 434}
 435
 436static ssize_t napi_defer_hard_irqs_store(struct device *dev,
 437					  struct device_attribute *attr,
 438					  const char *buf, size_t len)
 439{
 440	if (!capable(CAP_NET_ADMIN))
 441		return -EPERM;
 442
 443	return netdev_store(dev, attr, buf, len, change_napi_defer_hard_irqs);
 444}
 445NETDEVICE_SHOW_RW(napi_defer_hard_irqs, fmt_uint);
 446
 447static ssize_t ifalias_store(struct device *dev, struct device_attribute *attr,
 448			     const char *buf, size_t len)
 449{
 450	struct net_device *netdev = to_net_dev(dev);
 451	struct net *net = dev_net(netdev);
 452	size_t count = len;
 453	ssize_t ret = 0;
 454
 455	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 456		return -EPERM;
 457
 458	/* ignore trailing newline */
 459	if (len >  0 && buf[len - 1] == '\n')
 460		--count;
 461
 462	if (!rtnl_trylock())
 463		return restart_syscall();
 464
 465	if (dev_isalive(netdev)) {
 466		ret = dev_set_alias(netdev, buf, count);
 467		if (ret < 0)
 468			goto err;
 469		ret = len;
 470		netdev_state_change(netdev);
 471	}
 472err:
 473	rtnl_unlock();
 474
 475	return ret;
 476}
 477
 478static ssize_t ifalias_show(struct device *dev,
 479			    struct device_attribute *attr, char *buf)
 480{
 481	const struct net_device *netdev = to_net_dev(dev);
 482	char tmp[IFALIASZ];
 483	ssize_t ret = 0;
 484
 485	ret = dev_get_alias(netdev, tmp, sizeof(tmp));
 486	if (ret > 0)
 487		ret = sysfs_emit(buf, "%s\n", tmp);
 488	return ret;
 489}
 490static DEVICE_ATTR_RW(ifalias);
 491
 492static int change_group(struct net_device *dev, unsigned long new_group)
 493{
 494	dev_set_group(dev, (int)new_group);
 495	return 0;
 496}
 497
 498static ssize_t group_store(struct device *dev, struct device_attribute *attr,
 499			   const char *buf, size_t len)
 500{
 501	return netdev_store(dev, attr, buf, len, change_group);
 502}
 503NETDEVICE_SHOW(group, fmt_dec);
 504static DEVICE_ATTR(netdev_group, 0644, group_show, group_store);
 505
 506static int change_proto_down(struct net_device *dev, unsigned long proto_down)
 507{
 508	return dev_change_proto_down(dev, (bool)proto_down);
 509}
 510
 511static ssize_t proto_down_store(struct device *dev,
 512				struct device_attribute *attr,
 513				const char *buf, size_t len)
 514{
 515	return netdev_store(dev, attr, buf, len, change_proto_down);
 516}
 517NETDEVICE_SHOW_RW(proto_down, fmt_dec);
 518
 519static ssize_t phys_port_id_show(struct device *dev,
 520				 struct device_attribute *attr, char *buf)
 521{
 522	struct net_device *netdev = to_net_dev(dev);
 523	ssize_t ret = -EINVAL;
 524
 525	/* The check is also done in dev_get_phys_port_id; this helps returning
 526	 * early without hitting the trylock/restart below.
 527	 */
 528	if (!netdev->netdev_ops->ndo_get_phys_port_id)
 529		return -EOPNOTSUPP;
 530
 531	if (!rtnl_trylock())
 532		return restart_syscall();
 533
 534	if (dev_isalive(netdev)) {
 535		struct netdev_phys_item_id ppid;
 536
 537		ret = dev_get_phys_port_id(netdev, &ppid);
 538		if (!ret)
 539			ret = sysfs_emit(buf, "%*phN\n", ppid.id_len, ppid.id);
 540	}
 541	rtnl_unlock();
 542
 543	return ret;
 544}
 545static DEVICE_ATTR_RO(phys_port_id);
 546
 547static ssize_t phys_port_name_show(struct device *dev,
 548				   struct device_attribute *attr, char *buf)
 549{
 550	struct net_device *netdev = to_net_dev(dev);
 551	ssize_t ret = -EINVAL;
 552
 553	/* The checks are also done in dev_get_phys_port_name; this helps
 554	 * returning early without hitting the trylock/restart below.
 555	 */
 556	if (!netdev->netdev_ops->ndo_get_phys_port_name &&
 557	    !netdev->devlink_port)
 558		return -EOPNOTSUPP;
 559
 560	if (!rtnl_trylock())
 561		return restart_syscall();
 562
 563	if (dev_isalive(netdev)) {
 564		char name[IFNAMSIZ];
 565
 566		ret = dev_get_phys_port_name(netdev, name, sizeof(name));
 567		if (!ret)
 568			ret = sysfs_emit(buf, "%s\n", name);
 569	}
 570	rtnl_unlock();
 571
 572	return ret;
 573}
 574static DEVICE_ATTR_RO(phys_port_name);
 575
 576static ssize_t phys_switch_id_show(struct device *dev,
 577				   struct device_attribute *attr, char *buf)
 578{
 579	struct net_device *netdev = to_net_dev(dev);
 580	ssize_t ret = -EINVAL;
 581
 582	/* The checks are also done in dev_get_phys_port_name; this helps
 583	 * returning early without hitting the trylock/restart below. This works
 584	 * because recurse is false when calling dev_get_port_parent_id.
 585	 */
 586	if (!netdev->netdev_ops->ndo_get_port_parent_id &&
 587	    !netdev->devlink_port)
 588		return -EOPNOTSUPP;
 589
 590	if (!rtnl_trylock())
 591		return restart_syscall();
 592
 593	if (dev_isalive(netdev)) {
 594		struct netdev_phys_item_id ppid = { };
 595
 596		ret = dev_get_port_parent_id(netdev, &ppid, false);
 597		if (!ret)
 598			ret = sysfs_emit(buf, "%*phN\n", ppid.id_len, ppid.id);
 599	}
 600	rtnl_unlock();
 601
 602	return ret;
 603}
 604static DEVICE_ATTR_RO(phys_switch_id);
 605
 606static ssize_t threaded_show(struct device *dev,
 607			     struct device_attribute *attr, char *buf)
 608{
 609	struct net_device *netdev = to_net_dev(dev);
 610	ssize_t ret = -EINVAL;
 611
 612	rcu_read_lock();
 613
 614	if (dev_isalive(netdev))
 615		ret = sysfs_emit(buf, fmt_dec, READ_ONCE(netdev->threaded));
 616
 617	rcu_read_unlock();
 618
 619	return ret;
 620}
 621
 622static int modify_napi_threaded(struct net_device *dev, unsigned long val)
 
 623{
 624	int ret;
 625
 626	if (list_empty(&dev->napi_list))
 627		return -EOPNOTSUPP;
 628
 629	if (val != 0 && val != 1)
 630		return -EOPNOTSUPP;
 631
 632	ret = dev_set_threaded(dev, val);
 633
 634	return ret;
 635}
 636
 637static ssize_t threaded_store(struct device *dev,
 638			      struct device_attribute *attr,
 639			      const char *buf, size_t len)
 640{
 641	return netdev_store(dev, attr, buf, len, modify_napi_threaded);
 642}
 643static DEVICE_ATTR_RW(threaded);
 644
 645static struct attribute *net_class_attrs[] __ro_after_init = {
 646	&dev_attr_netdev_group.attr,
 647	&dev_attr_type.attr,
 648	&dev_attr_dev_id.attr,
 649	&dev_attr_dev_port.attr,
 650	&dev_attr_iflink.attr,
 651	&dev_attr_ifindex.attr,
 652	&dev_attr_name_assign_type.attr,
 653	&dev_attr_addr_assign_type.attr,
 654	&dev_attr_addr_len.attr,
 655	&dev_attr_link_mode.attr,
 656	&dev_attr_address.attr,
 657	&dev_attr_broadcast.attr,
 658	&dev_attr_speed.attr,
 659	&dev_attr_duplex.attr,
 660	&dev_attr_dormant.attr,
 661	&dev_attr_testing.attr,
 662	&dev_attr_operstate.attr,
 663	&dev_attr_carrier_changes.attr,
 664	&dev_attr_ifalias.attr,
 665	&dev_attr_carrier.attr,
 666	&dev_attr_mtu.attr,
 667	&dev_attr_flags.attr,
 668	&dev_attr_tx_queue_len.attr,
 669	&dev_attr_gro_flush_timeout.attr,
 670	&dev_attr_napi_defer_hard_irqs.attr,
 671	&dev_attr_phys_port_id.attr,
 672	&dev_attr_phys_port_name.attr,
 673	&dev_attr_phys_switch_id.attr,
 674	&dev_attr_proto_down.attr,
 675	&dev_attr_carrier_up_count.attr,
 676	&dev_attr_carrier_down_count.attr,
 677	&dev_attr_threaded.attr,
 678	NULL,
 679};
 680ATTRIBUTE_GROUPS(net_class);
 681
 682/* Show a given an attribute in the statistics group */
 683static ssize_t netstat_show(const struct device *d,
 684			    struct device_attribute *attr, char *buf,
 685			    unsigned long offset)
 686{
 687	struct net_device *dev = to_net_dev(d);
 688	ssize_t ret = -EINVAL;
 689
 690	WARN_ON(offset > sizeof(struct rtnl_link_stats64) ||
 691		offset % sizeof(u64) != 0);
 692
 693	rcu_read_lock();
 694	if (dev_isalive(dev)) {
 695		struct rtnl_link_stats64 temp;
 696		const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp);
 697
 698		ret = sysfs_emit(buf, fmt_u64, *(u64 *)(((u8 *)stats) + offset));
 699	}
 700	rcu_read_unlock();
 701	return ret;
 702}
 703
 704/* generate a read-only statistics attribute */
 705#define NETSTAT_ENTRY(name)						\
 706static ssize_t name##_show(struct device *d,				\
 707			   struct device_attribute *attr, char *buf)	\
 708{									\
 709	return netstat_show(d, attr, buf,				\
 710			    offsetof(struct rtnl_link_stats64, name));	\
 711}									\
 712static DEVICE_ATTR_RO(name)
 713
 714NETSTAT_ENTRY(rx_packets);
 715NETSTAT_ENTRY(tx_packets);
 716NETSTAT_ENTRY(rx_bytes);
 717NETSTAT_ENTRY(tx_bytes);
 718NETSTAT_ENTRY(rx_errors);
 719NETSTAT_ENTRY(tx_errors);
 720NETSTAT_ENTRY(rx_dropped);
 721NETSTAT_ENTRY(tx_dropped);
 722NETSTAT_ENTRY(multicast);
 723NETSTAT_ENTRY(collisions);
 724NETSTAT_ENTRY(rx_length_errors);
 725NETSTAT_ENTRY(rx_over_errors);
 726NETSTAT_ENTRY(rx_crc_errors);
 727NETSTAT_ENTRY(rx_frame_errors);
 728NETSTAT_ENTRY(rx_fifo_errors);
 729NETSTAT_ENTRY(rx_missed_errors);
 730NETSTAT_ENTRY(tx_aborted_errors);
 731NETSTAT_ENTRY(tx_carrier_errors);
 732NETSTAT_ENTRY(tx_fifo_errors);
 733NETSTAT_ENTRY(tx_heartbeat_errors);
 734NETSTAT_ENTRY(tx_window_errors);
 735NETSTAT_ENTRY(rx_compressed);
 736NETSTAT_ENTRY(tx_compressed);
 737NETSTAT_ENTRY(rx_nohandler);
 738
 739static struct attribute *netstat_attrs[] __ro_after_init = {
 740	&dev_attr_rx_packets.attr,
 741	&dev_attr_tx_packets.attr,
 742	&dev_attr_rx_bytes.attr,
 743	&dev_attr_tx_bytes.attr,
 744	&dev_attr_rx_errors.attr,
 745	&dev_attr_tx_errors.attr,
 746	&dev_attr_rx_dropped.attr,
 747	&dev_attr_tx_dropped.attr,
 748	&dev_attr_multicast.attr,
 749	&dev_attr_collisions.attr,
 750	&dev_attr_rx_length_errors.attr,
 751	&dev_attr_rx_over_errors.attr,
 752	&dev_attr_rx_crc_errors.attr,
 753	&dev_attr_rx_frame_errors.attr,
 754	&dev_attr_rx_fifo_errors.attr,
 755	&dev_attr_rx_missed_errors.attr,
 756	&dev_attr_tx_aborted_errors.attr,
 757	&dev_attr_tx_carrier_errors.attr,
 758	&dev_attr_tx_fifo_errors.attr,
 759	&dev_attr_tx_heartbeat_errors.attr,
 760	&dev_attr_tx_window_errors.attr,
 761	&dev_attr_rx_compressed.attr,
 762	&dev_attr_tx_compressed.attr,
 763	&dev_attr_rx_nohandler.attr,
 764	NULL
 765};
 766
 767static const struct attribute_group netstat_group = {
 
 768	.name  = "statistics",
 769	.attrs  = netstat_attrs,
 770};
 771
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 772static struct attribute *wireless_attrs[] = {
 
 
 
 
 
 
 
 
 
 
 773	NULL
 774};
 775
 776static const struct attribute_group wireless_group = {
 777	.name = "wireless",
 778	.attrs = wireless_attrs,
 779};
 780
 781static bool wireless_group_needed(struct net_device *ndev)
 782{
 783#if IS_ENABLED(CONFIG_CFG80211)
 784	if (ndev->ieee80211_ptr)
 785		return true;
 786#endif
 787#if IS_ENABLED(CONFIG_WIRELESS_EXT)
 788	if (ndev->wireless_handlers)
 789		return true;
 790#endif
 791	return false;
 792}
 793
 794#else /* CONFIG_SYSFS */
 795#define net_class_groups	NULL
 796#endif /* CONFIG_SYSFS */
 797
 798#ifdef CONFIG_SYSFS
 799#define to_rx_queue_attr(_attr) \
 800	container_of(_attr, struct rx_queue_attribute, attr)
 
 
 
 
 
 
 
 
 
 
 801
 802#define to_rx_queue(obj) container_of(obj, struct netdev_rx_queue, kobj)
 803
 804static ssize_t rx_queue_attr_show(struct kobject *kobj, struct attribute *attr,
 805				  char *buf)
 806{
 807	const struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
 808	struct netdev_rx_queue *queue = to_rx_queue(kobj);
 809
 810	if (!attribute->show)
 811		return -EIO;
 812
 813	return attribute->show(queue, buf);
 814}
 815
 816static ssize_t rx_queue_attr_store(struct kobject *kobj, struct attribute *attr,
 817				   const char *buf, size_t count)
 818{
 819	const struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
 820	struct netdev_rx_queue *queue = to_rx_queue(kobj);
 821
 822	if (!attribute->store)
 823		return -EIO;
 824
 825	return attribute->store(queue, buf, count);
 826}
 827
 828static const struct sysfs_ops rx_queue_sysfs_ops = {
 829	.show = rx_queue_attr_show,
 830	.store = rx_queue_attr_store,
 831};
 832
 833#ifdef CONFIG_RPS
 834static ssize_t show_rps_map(struct netdev_rx_queue *queue, char *buf)
 835{
 836	struct rps_map *map;
 837	cpumask_var_t mask;
 838	int i, len;
 
 839
 840	if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
 841		return -ENOMEM;
 842
 843	rcu_read_lock();
 844	map = rcu_dereference(queue->rps_map);
 845	if (map)
 846		for (i = 0; i < map->len; i++)
 847			cpumask_set_cpu(map->cpus[i], mask);
 848
 849	len = sysfs_emit(buf, "%*pb\n", cpumask_pr_args(mask));
 
 
 
 
 
 850	rcu_read_unlock();
 851	free_cpumask_var(mask);
 852
 853	return len < PAGE_SIZE ? len : -EINVAL;
 
 
 854}
 855
 856static int netdev_rx_queue_set_rps_mask(struct netdev_rx_queue *queue,
 857					cpumask_var_t mask)
 
 858{
 859	static DEFINE_MUTEX(rps_map_mutex);
 860	struct rps_map *old_map, *map;
 861	int cpu, i;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 862
 863	map = kzalloc(max_t(unsigned int,
 864			    RPS_MAP_SIZE(cpumask_weight(mask)), L1_CACHE_BYTES),
 865		      GFP_KERNEL);
 866	if (!map)
 
 867		return -ENOMEM;
 
 868
 869	i = 0;
 870	for_each_cpu_and(cpu, mask, cpu_online_mask)
 871		map->cpus[i++] = cpu;
 872
 873	if (i) {
 874		map->len = i;
 875	} else {
 876		kfree(map);
 877		map = NULL;
 878	}
 879
 880	mutex_lock(&rps_map_mutex);
 881	old_map = rcu_dereference_protected(queue->rps_map,
 882					    mutex_is_locked(&rps_map_mutex));
 883	rcu_assign_pointer(queue->rps_map, map);
 
 884
 885	if (map)
 886		static_branch_inc(&rps_needed);
 887	if (old_map)
 888		static_branch_dec(&rps_needed);
 889
 890	mutex_unlock(&rps_map_mutex);
 891
 892	if (old_map)
 893		kfree_rcu(old_map, rcu);
 894	return 0;
 895}
 896
 897int rps_cpumask_housekeeping(struct cpumask *mask)
 898{
 899	if (!cpumask_empty(mask)) {
 900		cpumask_and(mask, mask, housekeeping_cpumask(HK_TYPE_DOMAIN));
 901		cpumask_and(mask, mask, housekeeping_cpumask(HK_TYPE_WQ));
 902		if (cpumask_empty(mask))
 903			return -EINVAL;
 904	}
 905	return 0;
 906}
 907
 908static ssize_t store_rps_map(struct netdev_rx_queue *queue,
 909			     const char *buf, size_t len)
 910{
 911	cpumask_var_t mask;
 912	int err;
 913
 914	if (!capable(CAP_NET_ADMIN))
 915		return -EPERM;
 916
 917	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
 918		return -ENOMEM;
 919
 920	err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
 921	if (err)
 922		goto out;
 923
 924	err = rps_cpumask_housekeeping(mask);
 925	if (err)
 926		goto out;
 927
 928	err = netdev_rx_queue_set_rps_mask(queue, mask);
 929
 930out:
 931	free_cpumask_var(mask);
 932	return err ? : len;
 933}
 934
 935static ssize_t show_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
 
 936					   char *buf)
 937{
 938	struct rps_dev_flow_table *flow_table;
 939	unsigned long val = 0;
 940
 941	rcu_read_lock();
 942	flow_table = rcu_dereference(queue->rps_flow_table);
 943	if (flow_table)
 944		val = (unsigned long)flow_table->mask + 1;
 945	rcu_read_unlock();
 946
 947	return sysfs_emit(buf, "%lu\n", val);
 
 
 
 
 
 
 
 
 948}
 949
 950static void rps_dev_flow_table_release(struct rcu_head *rcu)
 951{
 952	struct rps_dev_flow_table *table = container_of(rcu,
 953	    struct rps_dev_flow_table, rcu);
 954	vfree(table);
 
 
 955}
 956
 957static ssize_t store_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
 958					    const char *buf, size_t len)
 
 959{
 960	unsigned long mask, count;
 961	struct rps_dev_flow_table *table, *old_table;
 962	static DEFINE_SPINLOCK(rps_dev_flow_lock);
 963	int rc;
 964
 965	if (!capable(CAP_NET_ADMIN))
 966		return -EPERM;
 967
 968	rc = kstrtoul(buf, 0, &count);
 969	if (rc < 0)
 970		return rc;
 971
 972	if (count) {
 973		mask = count - 1;
 974		/* mask = roundup_pow_of_two(count) - 1;
 975		 * without overflows...
 976		 */
 977		while ((mask | (mask >> 1)) != mask)
 978			mask |= (mask >> 1);
 979		/* On 64 bit arches, must check mask fits in table->mask (u32),
 980		 * and on 32bit arches, must check
 981		 * RPS_DEV_FLOW_TABLE_SIZE(mask + 1) doesn't overflow.
 982		 */
 983#if BITS_PER_LONG > 32
 984		if (mask > (unsigned long)(u32)mask)
 985			return -EINVAL;
 986#else
 987		if (mask > (ULONG_MAX - RPS_DEV_FLOW_TABLE_SIZE(1))
 988				/ sizeof(struct rps_dev_flow)) {
 989			/* Enforce a limit to prevent overflow */
 990			return -EINVAL;
 991		}
 992#endif
 993		table = vmalloc(RPS_DEV_FLOW_TABLE_SIZE(mask + 1));
 994		if (!table)
 995			return -ENOMEM;
 996
 997		table->mask = mask;
 998		for (count = 0; count <= mask; count++)
 999			table->flows[count].cpu = RPS_NO_CPU;
1000	} else {
1001		table = NULL;
1002	}
1003
1004	spin_lock(&rps_dev_flow_lock);
1005	old_table = rcu_dereference_protected(queue->rps_flow_table,
1006					      lockdep_is_held(&rps_dev_flow_lock));
1007	rcu_assign_pointer(queue->rps_flow_table, table);
1008	spin_unlock(&rps_dev_flow_lock);
1009
1010	if (old_table)
1011		call_rcu(&old_table->rcu, rps_dev_flow_table_release);
1012
1013	return len;
1014}
1015
1016static struct rx_queue_attribute rps_cpus_attribute __ro_after_init
1017	= __ATTR(rps_cpus, 0644, show_rps_map, store_rps_map);
1018
1019static struct rx_queue_attribute rps_dev_flow_table_cnt_attribute __ro_after_init
1020	= __ATTR(rps_flow_cnt, 0644,
1021		 show_rps_dev_flow_table_cnt, store_rps_dev_flow_table_cnt);
1022#endif /* CONFIG_RPS */
1023
1024static struct attribute *rx_queue_default_attrs[] __ro_after_init = {
1025#ifdef CONFIG_RPS
 
 
 
1026	&rps_cpus_attribute.attr,
1027	&rps_dev_flow_table_cnt_attribute.attr,
1028#endif
1029	NULL
1030};
1031ATTRIBUTE_GROUPS(rx_queue_default);
1032
1033static void rx_queue_release(struct kobject *kobj)
1034{
1035	struct netdev_rx_queue *queue = to_rx_queue(kobj);
1036#ifdef CONFIG_RPS
1037	struct rps_map *map;
1038	struct rps_dev_flow_table *flow_table;
1039
 
1040	map = rcu_dereference_protected(queue->rps_map, 1);
1041	if (map) {
1042		RCU_INIT_POINTER(queue->rps_map, NULL);
1043		kfree_rcu(map, rcu);
1044	}
1045
1046	flow_table = rcu_dereference_protected(queue->rps_flow_table, 1);
1047	if (flow_table) {
1048		RCU_INIT_POINTER(queue->rps_flow_table, NULL);
1049		call_rcu(&flow_table->rcu, rps_dev_flow_table_release);
1050	}
1051#endif
1052
1053	memset(kobj, 0, sizeof(*kobj));
1054	netdev_put(queue->dev, &queue->dev_tracker);
1055}
1056
1057static const void *rx_queue_namespace(const struct kobject *kobj)
1058{
1059	struct netdev_rx_queue *queue = to_rx_queue(kobj);
1060	struct device *dev = &queue->dev->dev;
1061	const void *ns = NULL;
1062
1063	if (dev->class && dev->class->namespace)
1064		ns = dev->class->namespace(dev);
1065
1066	return ns;
1067}
1068
1069static void rx_queue_get_ownership(const struct kobject *kobj,
1070				   kuid_t *uid, kgid_t *gid)
1071{
1072	const struct net *net = rx_queue_namespace(kobj);
1073
1074	net_ns_get_ownership(net, uid, gid);
1075}
1076
1077static const struct kobj_type rx_queue_ktype = {
1078	.sysfs_ops = &rx_queue_sysfs_ops,
1079	.release = rx_queue_release,
1080	.default_groups = rx_queue_default_groups,
1081	.namespace = rx_queue_namespace,
1082	.get_ownership = rx_queue_get_ownership,
1083};
1084
1085static int rx_queue_default_mask(struct net_device *dev,
1086				 struct netdev_rx_queue *queue)
1087{
1088#if IS_ENABLED(CONFIG_RPS) && IS_ENABLED(CONFIG_SYSCTL)
1089	struct cpumask *rps_default_mask = READ_ONCE(dev_net(dev)->core.rps_default_mask);
1090
1091	if (rps_default_mask && !cpumask_empty(rps_default_mask))
1092		return netdev_rx_queue_set_rps_mask(queue, rps_default_mask);
1093#endif
1094	return 0;
1095}
1096
1097static int rx_queue_add_kobject(struct net_device *dev, int index)
1098{
1099	struct netdev_rx_queue *queue = dev->_rx + index;
1100	struct kobject *kobj = &queue->kobj;
1101	int error = 0;
1102
1103	/* Kobject_put later will trigger rx_queue_release call which
1104	 * decreases dev refcount: Take that reference here
1105	 */
1106	netdev_hold(queue->dev, &queue->dev_tracker, GFP_KERNEL);
1107
1108	kobj->kset = dev->queues_kset;
1109	error = kobject_init_and_add(kobj, &rx_queue_ktype, NULL,
1110				     "rx-%u", index);
1111	if (error)
1112		goto err;
1113
1114	if (dev->sysfs_rx_queue_group) {
1115		error = sysfs_create_group(kobj, dev->sysfs_rx_queue_group);
1116		if (error)
1117			goto err;
1118	}
1119
1120	error = rx_queue_default_mask(dev, queue);
1121	if (error)
1122		goto err;
1123
1124	kobject_uevent(kobj, KOBJ_ADD);
1125
1126	return error;
1127
1128err:
1129	kobject_put(kobj);
1130	return error;
1131}
1132
1133static int rx_queue_change_owner(struct net_device *dev, int index, kuid_t kuid,
1134				 kgid_t kgid)
1135{
1136	struct netdev_rx_queue *queue = dev->_rx + index;
1137	struct kobject *kobj = &queue->kobj;
1138	int error;
1139
1140	error = sysfs_change_owner(kobj, kuid, kgid);
1141	if (error)
1142		return error;
1143
1144	if (dev->sysfs_rx_queue_group)
1145		error = sysfs_group_change_owner(
1146			kobj, dev->sysfs_rx_queue_group, kuid, kgid);
1147
1148	return error;
1149}
1150#endif /* CONFIG_SYSFS */
1151
1152int
1153net_rx_queue_update_kobjects(struct net_device *dev, int old_num, int new_num)
1154{
1155#ifdef CONFIG_SYSFS
1156	int i;
1157	int error = 0;
1158
1159#ifndef CONFIG_RPS
1160	if (!dev->sysfs_rx_queue_group)
1161		return 0;
1162#endif
1163	for (i = old_num; i < new_num; i++) {
1164		error = rx_queue_add_kobject(dev, i);
1165		if (error) {
1166			new_num = old_num;
1167			break;
1168		}
1169	}
1170
1171	while (--i >= new_num) {
1172		struct kobject *kobj = &dev->_rx[i].kobj;
1173
1174		if (!refcount_read(&dev_net(dev)->ns.count))
1175			kobj->uevent_suppress = 1;
1176		if (dev->sysfs_rx_queue_group)
1177			sysfs_remove_group(kobj, dev->sysfs_rx_queue_group);
1178		kobject_put(kobj);
1179	}
1180
1181	return error;
1182#else
1183	return 0;
1184#endif
1185}
1186
1187static int net_rx_queue_change_owner(struct net_device *dev, int num,
1188				     kuid_t kuid, kgid_t kgid)
1189{
1190#ifdef CONFIG_SYSFS
1191	int error = 0;
1192	int i;
1193
1194#ifndef CONFIG_RPS
1195	if (!dev->sysfs_rx_queue_group)
1196		return 0;
1197#endif
1198	for (i = 0; i < num; i++) {
1199		error = rx_queue_change_owner(dev, i, kuid, kgid);
1200		if (error)
1201			break;
1202	}
1203
1204	return error;
1205#else
1206	return 0;
1207#endif
1208}
1209
1210#ifdef CONFIG_SYSFS
1211/*
1212 * netdev_queue sysfs structures and functions.
1213 */
1214struct netdev_queue_attribute {
1215	struct attribute attr;
1216	ssize_t (*show)(struct netdev_queue *queue, char *buf);
 
1217	ssize_t (*store)(struct netdev_queue *queue,
1218			 const char *buf, size_t len);
1219};
1220#define to_netdev_queue_attr(_attr) \
1221	container_of(_attr, struct netdev_queue_attribute, attr)
1222
1223#define to_netdev_queue(obj) container_of(obj, struct netdev_queue, kobj)
1224
1225static ssize_t netdev_queue_attr_show(struct kobject *kobj,
1226				      struct attribute *attr, char *buf)
1227{
1228	const struct netdev_queue_attribute *attribute
1229		= to_netdev_queue_attr(attr);
1230	struct netdev_queue *queue = to_netdev_queue(kobj);
1231
1232	if (!attribute->show)
1233		return -EIO;
1234
1235	return attribute->show(queue, buf);
1236}
1237
1238static ssize_t netdev_queue_attr_store(struct kobject *kobj,
1239				       struct attribute *attr,
1240				       const char *buf, size_t count)
1241{
1242	const struct netdev_queue_attribute *attribute
1243		= to_netdev_queue_attr(attr);
1244	struct netdev_queue *queue = to_netdev_queue(kobj);
1245
1246	if (!attribute->store)
1247		return -EIO;
1248
1249	return attribute->store(queue, buf, count);
1250}
1251
1252static const struct sysfs_ops netdev_queue_sysfs_ops = {
1253	.show = netdev_queue_attr_show,
1254	.store = netdev_queue_attr_store,
1255};
1256
1257static ssize_t tx_timeout_show(struct netdev_queue *queue, char *buf)
1258{
1259	unsigned long trans_timeout = atomic_long_read(&queue->trans_timeout);
1260
1261	return sysfs_emit(buf, fmt_ulong, trans_timeout);
1262}
1263
1264static unsigned int get_netdev_queue_index(struct netdev_queue *queue)
1265{
1266	struct net_device *dev = queue->dev;
1267	unsigned int i;
1268
1269	i = queue - dev->_tx;
1270	BUG_ON(i >= dev->num_tx_queues);
1271
1272	return i;
1273}
1274
1275static ssize_t traffic_class_show(struct netdev_queue *queue,
1276				  char *buf)
1277{
1278	struct net_device *dev = queue->dev;
1279	int num_tc, tc;
1280	int index;
1281
1282	if (!netif_is_multiqueue(dev))
1283		return -ENOENT;
1284
1285	if (!rtnl_trylock())
1286		return restart_syscall();
1287
1288	index = get_netdev_queue_index(queue);
1289
1290	/* If queue belongs to subordinate dev use its TC mapping */
1291	dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev;
1292
1293	num_tc = dev->num_tc;
1294	tc = netdev_txq_to_tc(dev, index);
1295
1296	rtnl_unlock();
1297
1298	if (tc < 0)
1299		return -EINVAL;
1300
1301	/* We can report the traffic class one of two ways:
1302	 * Subordinate device traffic classes are reported with the traffic
1303	 * class first, and then the subordinate class so for example TC0 on
1304	 * subordinate device 2 will be reported as "0-2". If the queue
1305	 * belongs to the root device it will be reported with just the
1306	 * traffic class, so just "0" for TC 0 for example.
1307	 */
1308	return num_tc < 0 ? sysfs_emit(buf, "%d%d\n", tc, num_tc) :
1309			    sysfs_emit(buf, "%d\n", tc);
1310}
1311
1312#ifdef CONFIG_XPS
1313static ssize_t tx_maxrate_show(struct netdev_queue *queue,
1314			       char *buf)
1315{
1316	return sysfs_emit(buf, "%lu\n", queue->tx_maxrate);
1317}
1318
1319static ssize_t tx_maxrate_store(struct netdev_queue *queue,
1320				const char *buf, size_t len)
1321{
1322	struct net_device *dev = queue->dev;
1323	int err, index = get_netdev_queue_index(queue);
1324	u32 rate = 0;
1325
1326	if (!capable(CAP_NET_ADMIN))
1327		return -EPERM;
1328
1329	/* The check is also done later; this helps returning early without
1330	 * hitting the trylock/restart below.
1331	 */
1332	if (!dev->netdev_ops->ndo_set_tx_maxrate)
1333		return -EOPNOTSUPP;
1334
1335	err = kstrtou32(buf, 10, &rate);
1336	if (err < 0)
1337		return err;
1338
1339	if (!rtnl_trylock())
1340		return restart_syscall();
1341
1342	err = -EOPNOTSUPP;
1343	if (dev->netdev_ops->ndo_set_tx_maxrate)
1344		err = dev->netdev_ops->ndo_set_tx_maxrate(dev, index, rate);
1345
1346	rtnl_unlock();
1347	if (!err) {
1348		queue->tx_maxrate = rate;
1349		return len;
1350	}
1351	return err;
1352}
1353
1354static struct netdev_queue_attribute queue_tx_maxrate __ro_after_init
1355	= __ATTR_RW(tx_maxrate);
1356#endif
1357
1358static struct netdev_queue_attribute queue_trans_timeout __ro_after_init
1359	= __ATTR_RO(tx_timeout);
1360
1361static struct netdev_queue_attribute queue_traffic_class __ro_after_init
1362	= __ATTR_RO(traffic_class);
1363
1364#ifdef CONFIG_BQL
1365/*
1366 * Byte queue limits sysfs structures and functions.
1367 */
1368static ssize_t bql_show(char *buf, unsigned int value)
1369{
1370	return sysfs_emit(buf, "%u\n", value);
1371}
1372
1373static ssize_t bql_set(const char *buf, const size_t count,
1374		       unsigned int *pvalue)
1375{
1376	unsigned int value;
1377	int err;
1378
1379	if (!strcmp(buf, "max") || !strcmp(buf, "max\n")) {
1380		value = DQL_MAX_LIMIT;
1381	} else {
1382		err = kstrtouint(buf, 10, &value);
1383		if (err < 0)
1384			return err;
1385		if (value > DQL_MAX_LIMIT)
1386			return -EINVAL;
1387	}
1388
1389	*pvalue = value;
1390
1391	return count;
1392}
1393
1394static ssize_t bql_show_hold_time(struct netdev_queue *queue,
 
1395				  char *buf)
1396{
1397	struct dql *dql = &queue->dql;
1398
1399	return sysfs_emit(buf, "%u\n", jiffies_to_msecs(dql->slack_hold_time));
1400}
1401
1402static ssize_t bql_set_hold_time(struct netdev_queue *queue,
 
1403				 const char *buf, size_t len)
1404{
1405	struct dql *dql = &queue->dql;
1406	unsigned int value;
1407	int err;
1408
1409	err = kstrtouint(buf, 10, &value);
1410	if (err < 0)
1411		return err;
1412
1413	dql->slack_hold_time = msecs_to_jiffies(value);
1414
1415	return len;
1416}
1417
1418static struct netdev_queue_attribute bql_hold_time_attribute __ro_after_init
1419	= __ATTR(hold_time, 0644,
1420		 bql_show_hold_time, bql_set_hold_time);
1421
1422static ssize_t bql_show_stall_thrs(struct netdev_queue *queue, char *buf)
1423{
1424	struct dql *dql = &queue->dql;
1425
1426	return sysfs_emit(buf, "%u\n", jiffies_to_msecs(dql->stall_thrs));
1427}
1428
1429static ssize_t bql_set_stall_thrs(struct netdev_queue *queue,
1430				  const char *buf, size_t len)
1431{
1432	struct dql *dql = &queue->dql;
1433	unsigned int value;
1434	int err;
1435
1436	err = kstrtouint(buf, 10, &value);
1437	if (err < 0)
1438		return err;
1439
1440	value = msecs_to_jiffies(value);
1441	if (value && (value < 4 || value > 4 / 2 * BITS_PER_LONG))
1442		return -ERANGE;
1443
1444	if (!dql->stall_thrs && value)
1445		dql->last_reap = jiffies;
1446	/* Force last_reap to be live */
1447	smp_wmb();
1448	dql->stall_thrs = value;
1449
1450	return len;
1451}
1452
1453static struct netdev_queue_attribute bql_stall_thrs_attribute __ro_after_init =
1454	__ATTR(stall_thrs, 0644, bql_show_stall_thrs, bql_set_stall_thrs);
1455
1456static ssize_t bql_show_stall_max(struct netdev_queue *queue, char *buf)
1457{
1458	return sysfs_emit(buf, "%u\n", READ_ONCE(queue->dql.stall_max));
1459}
1460
1461static ssize_t bql_set_stall_max(struct netdev_queue *queue,
1462				 const char *buf, size_t len)
1463{
1464	WRITE_ONCE(queue->dql.stall_max, 0);
1465	return len;
1466}
1467
1468static struct netdev_queue_attribute bql_stall_max_attribute __ro_after_init =
1469	__ATTR(stall_max, 0644, bql_show_stall_max, bql_set_stall_max);
1470
1471static ssize_t bql_show_stall_cnt(struct netdev_queue *queue, char *buf)
1472{
1473	struct dql *dql = &queue->dql;
1474
1475	return sysfs_emit(buf, "%lu\n", dql->stall_cnt);
1476}
1477
1478static struct netdev_queue_attribute bql_stall_cnt_attribute __ro_after_init =
1479	__ATTR(stall_cnt, 0444, bql_show_stall_cnt, NULL);
1480
1481static ssize_t bql_show_inflight(struct netdev_queue *queue,
 
1482				 char *buf)
1483{
1484	struct dql *dql = &queue->dql;
1485
1486	return sysfs_emit(buf, "%u\n", dql->num_queued - dql->num_completed);
1487}
1488
1489static struct netdev_queue_attribute bql_inflight_attribute __ro_after_init =
1490	__ATTR(inflight, 0444, bql_show_inflight, NULL);
1491
1492#define BQL_ATTR(NAME, FIELD)						\
1493static ssize_t bql_show_ ## NAME(struct netdev_queue *queue,		\
 
1494				 char *buf)				\
1495{									\
1496	return bql_show(buf, queue->dql.FIELD);				\
1497}									\
1498									\
1499static ssize_t bql_set_ ## NAME(struct netdev_queue *queue,		\
 
1500				const char *buf, size_t len)		\
1501{									\
1502	return bql_set(buf, len, &queue->dql.FIELD);			\
1503}									\
1504									\
1505static struct netdev_queue_attribute bql_ ## NAME ## _attribute __ro_after_init \
1506	= __ATTR(NAME, 0644,				\
1507		 bql_show_ ## NAME, bql_set_ ## NAME)
1508
1509BQL_ATTR(limit, limit);
1510BQL_ATTR(limit_max, max_limit);
1511BQL_ATTR(limit_min, min_limit);
1512
1513static struct attribute *dql_attrs[] __ro_after_init = {
1514	&bql_limit_attribute.attr,
1515	&bql_limit_max_attribute.attr,
1516	&bql_limit_min_attribute.attr,
1517	&bql_hold_time_attribute.attr,
1518	&bql_inflight_attribute.attr,
1519	&bql_stall_thrs_attribute.attr,
1520	&bql_stall_cnt_attribute.attr,
1521	&bql_stall_max_attribute.attr,
1522	NULL
1523};
1524
1525static const struct attribute_group dql_group = {
1526	.name  = "byte_queue_limits",
1527	.attrs  = dql_attrs,
1528};
1529#else
1530/* Fake declaration, all the code using it should be dead */
1531static const struct attribute_group dql_group = {};
1532#endif /* CONFIG_BQL */
1533
1534#ifdef CONFIG_XPS
1535static ssize_t xps_queue_show(struct net_device *dev, unsigned int index,
1536			      int tc, char *buf, enum xps_map_type type)
1537{
1538	struct xps_dev_maps *dev_maps;
1539	unsigned long *mask;
1540	unsigned int nr_ids;
1541	int j, len;
1542
1543	rcu_read_lock();
1544	dev_maps = rcu_dereference(dev->xps_maps[type]);
 
1545
1546	/* Default to nr_cpu_ids/dev->num_rx_queues and do not just return 0
1547	 * when dev_maps hasn't been allocated yet, to be backward compatible.
1548	 */
1549	nr_ids = dev_maps ? dev_maps->nr_ids :
1550		 (type == XPS_CPUS ? nr_cpu_ids : dev->num_rx_queues);
1551
1552	mask = bitmap_zalloc(nr_ids, GFP_NOWAIT);
1553	if (!mask) {
1554		rcu_read_unlock();
 
 
 
 
 
 
 
 
 
 
 
 
1555		return -ENOMEM;
1556	}
1557
1558	if (!dev_maps || tc >= dev_maps->num_tc)
1559		goto out_no_maps;
1560
1561	for (j = 0; j < nr_ids; j++) {
1562		int i, tci = j * dev_maps->num_tc + tc;
1563		struct xps_map *map;
1564
1565		map = rcu_dereference(dev_maps->attr_map[tci]);
1566		if (!map)
1567			continue;
1568
1569		for (i = map->len; i--;) {
1570			if (map->queues[i] == index) {
1571				__set_bit(j, mask);
1572				break;
 
 
1573			}
1574		}
1575	}
1576out_no_maps:
1577	rcu_read_unlock();
1578
1579	len = bitmap_print_to_pagebuf(false, buf, mask, nr_ids);
1580	bitmap_free(mask);
 
 
 
1581
1582	return len < PAGE_SIZE ? len : -EINVAL;
 
 
1583}
1584
1585static ssize_t xps_cpus_show(struct netdev_queue *queue, char *buf)
 
 
 
 
1586{
1587	struct net_device *dev = queue->dev;
1588	unsigned int index;
1589	int len, tc;
1590
1591	if (!netif_is_multiqueue(dev))
1592		return -ENOENT;
1593
1594	index = get_netdev_queue_index(queue);
1595
1596	if (!rtnl_trylock())
1597		return restart_syscall();
1598
1599	/* If queue belongs to subordinate dev use its map */
1600	dev = netdev_get_tx_queue(dev, index)->sb_dev ? : dev;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1601
1602	tc = netdev_txq_to_tc(dev, index);
1603	if (tc < 0) {
1604		rtnl_unlock();
1605		return -EINVAL;
1606	}
1607
1608	/* Make sure the subordinate device can't be freed */
1609	get_device(&dev->dev);
1610	rtnl_unlock();
1611
1612	len = xps_queue_show(dev, index, tc, buf, XPS_CPUS);
1613
1614	put_device(&dev->dev);
1615	return len;
1616}
1617
1618static ssize_t xps_cpus_store(struct netdev_queue *queue,
1619			      const char *buf, size_t len)
 
1620{
1621	struct net_device *dev = queue->dev;
1622	unsigned int index;
1623	cpumask_var_t mask;
1624	int err;
1625
1626	if (!netif_is_multiqueue(dev))
1627		return -ENOENT;
 
 
1628
1629	if (!capable(CAP_NET_ADMIN))
1630		return -EPERM;
1631
1632	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
1633		return -ENOMEM;
1634
1635	index = get_netdev_queue_index(queue);
1636
1637	err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
1638	if (err) {
1639		free_cpumask_var(mask);
1640		return err;
1641	}
1642
1643	if (!rtnl_trylock()) {
 
 
1644		free_cpumask_var(mask);
1645		return restart_syscall();
1646	}
1647
1648	err = netif_set_xps_queue(dev, mask, index);
1649	rtnl_unlock();
1650
1651	free_cpumask_var(mask);
1652
1653	return err ? : len;
1654}
1655
1656static struct netdev_queue_attribute xps_cpus_attribute __ro_after_init
1657	= __ATTR_RW(xps_cpus);
1658
1659static ssize_t xps_rxqs_show(struct netdev_queue *queue, char *buf)
1660{
1661	struct net_device *dev = queue->dev;
1662	unsigned int index;
1663	int tc;
1664
1665	index = get_netdev_queue_index(queue);
1666
1667	if (!rtnl_trylock())
1668		return restart_syscall();
1669
1670	tc = netdev_txq_to_tc(dev, index);
1671	rtnl_unlock();
1672	if (tc < 0)
1673		return -EINVAL;
1674
1675	return xps_queue_show(dev, index, tc, buf, XPS_RXQS);
1676}
1677
1678static ssize_t xps_rxqs_store(struct netdev_queue *queue, const char *buf,
1679			      size_t len)
1680{
1681	struct net_device *dev = queue->dev;
1682	struct net *net = dev_net(dev);
1683	unsigned long *mask;
1684	unsigned int index;
1685	int err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1686
1687	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
1688		return -EPERM;
 
 
 
 
 
 
 
1689
1690	mask = bitmap_zalloc(dev->num_rx_queues, GFP_KERNEL);
1691	if (!mask)
1692		return -ENOMEM;
 
 
 
1693
1694	index = get_netdev_queue_index(queue);
 
1695
1696	err = bitmap_parse(buf, len, mask, dev->num_rx_queues);
1697	if (err) {
1698		bitmap_free(mask);
1699		return err;
1700	}
1701
1702	if (!rtnl_trylock()) {
1703		bitmap_free(mask);
1704		return restart_syscall();
1705	}
1706
1707	cpus_read_lock();
1708	err = __netif_set_xps_queue(dev, mask, index, XPS_RXQS);
1709	cpus_read_unlock();
1710
1711	rtnl_unlock();
 
1712
1713	bitmap_free(mask);
1714	return err ? : len;
 
 
 
 
 
 
1715}
1716
1717static struct netdev_queue_attribute xps_rxqs_attribute __ro_after_init
1718	= __ATTR_RW(xps_rxqs);
1719#endif /* CONFIG_XPS */
1720
1721static struct attribute *netdev_queue_default_attrs[] __ro_after_init = {
1722	&queue_trans_timeout.attr,
1723	&queue_traffic_class.attr,
1724#ifdef CONFIG_XPS
1725	&xps_cpus_attribute.attr,
1726	&xps_rxqs_attribute.attr,
1727	&queue_tx_maxrate.attr,
1728#endif
1729	NULL
1730};
1731ATTRIBUTE_GROUPS(netdev_queue_default);
1732
1733static void netdev_queue_release(struct kobject *kobj)
1734{
1735	struct netdev_queue *queue = to_netdev_queue(kobj);
1736
1737	memset(kobj, 0, sizeof(*kobj));
1738	netdev_put(queue->dev, &queue->dev_tracker);
1739}
1740
1741static const void *netdev_queue_namespace(const struct kobject *kobj)
1742{
1743	struct netdev_queue *queue = to_netdev_queue(kobj);
1744	struct device *dev = &queue->dev->dev;
1745	const void *ns = NULL;
1746
1747	if (dev->class && dev->class->namespace)
1748		ns = dev->class->namespace(dev);
1749
1750	return ns;
1751}
1752
1753static void netdev_queue_get_ownership(const struct kobject *kobj,
1754				       kuid_t *uid, kgid_t *gid)
1755{
1756	const struct net *net = netdev_queue_namespace(kobj);
1757
1758	net_ns_get_ownership(net, uid, gid);
 
1759}
1760
1761static const struct kobj_type netdev_queue_ktype = {
1762	.sysfs_ops = &netdev_queue_sysfs_ops,
1763	.release = netdev_queue_release,
1764	.default_groups = netdev_queue_default_groups,
1765	.namespace = netdev_queue_namespace,
1766	.get_ownership = netdev_queue_get_ownership,
1767};
1768
1769static bool netdev_uses_bql(const struct net_device *dev)
1770{
1771	if (dev->lltx || (dev->priv_flags & IFF_NO_QUEUE))
1772		return false;
1773
1774	return IS_ENABLED(CONFIG_BQL);
1775}
1776
1777static int netdev_queue_add_kobject(struct net_device *dev, int index)
1778{
1779	struct netdev_queue *queue = dev->_tx + index;
1780	struct kobject *kobj = &queue->kobj;
1781	int error = 0;
1782
1783	/* Kobject_put later will trigger netdev_queue_release call
1784	 * which decreases dev refcount: Take that reference here
1785	 */
1786	netdev_hold(queue->dev, &queue->dev_tracker, GFP_KERNEL);
1787
1788	kobj->kset = dev->queues_kset;
1789	error = kobject_init_and_add(kobj, &netdev_queue_ktype, NULL,
1790				     "tx-%u", index);
1791	if (error)
1792		goto err;
1793
1794	if (netdev_uses_bql(dev)) {
1795		error = sysfs_create_group(kobj, &dql_group);
1796		if (error)
1797			goto err;
1798	}
1799
1800	kobject_uevent(kobj, KOBJ_ADD);
1801	return 0;
1802
1803err:
 
1804	kobject_put(kobj);
1805	return error;
1806}
1807
1808static int tx_queue_change_owner(struct net_device *ndev, int index,
1809				 kuid_t kuid, kgid_t kgid)
1810{
1811	struct netdev_queue *queue = ndev->_tx + index;
1812	struct kobject *kobj = &queue->kobj;
1813	int error;
1814
1815	error = sysfs_change_owner(kobj, kuid, kgid);
1816	if (error)
1817		return error;
1818
1819	if (netdev_uses_bql(ndev))
1820		error = sysfs_group_change_owner(kobj, &dql_group, kuid, kgid);
1821
1822	return error;
1823}
1824#endif /* CONFIG_SYSFS */
1825
1826int
1827netdev_queue_update_kobjects(struct net_device *dev, int old_num, int new_num)
1828{
1829#ifdef CONFIG_SYSFS
1830	int i;
1831	int error = 0;
1832
1833	/* Tx queue kobjects are allowed to be updated when a device is being
1834	 * unregistered, but solely to remove queues from qdiscs. Any path
1835	 * adding queues should be fixed.
1836	 */
1837	WARN(dev->reg_state == NETREG_UNREGISTERING && new_num > old_num,
1838	     "New queues can't be registered after device unregistration.");
1839
1840	for (i = old_num; i < new_num; i++) {
1841		error = netdev_queue_add_kobject(dev, i);
1842		if (error) {
1843			new_num = old_num;
1844			break;
1845		}
1846	}
1847
1848	while (--i >= new_num) {
1849		struct netdev_queue *queue = dev->_tx + i;
1850
1851		if (!refcount_read(&dev_net(dev)->ns.count))
1852			queue->kobj.uevent_suppress = 1;
1853
1854		if (netdev_uses_bql(dev))
1855			sysfs_remove_group(&queue->kobj, &dql_group);
1856
 
 
 
1857		kobject_put(&queue->kobj);
1858	}
1859
1860	return error;
1861#else
1862	return 0;
1863#endif /* CONFIG_SYSFS */
1864}
1865
1866static int net_tx_queue_change_owner(struct net_device *dev, int num,
1867				     kuid_t kuid, kgid_t kgid)
1868{
1869#ifdef CONFIG_SYSFS
1870	int error = 0;
1871	int i;
1872
1873	for (i = 0; i < num; i++) {
1874		error = tx_queue_change_owner(dev, i, kuid, kgid);
1875		if (error)
1876			break;
1877	}
1878
1879	return error;
1880#else
1881	return 0;
1882#endif /* CONFIG_SYSFS */
1883}
1884
1885static int register_queue_kobjects(struct net_device *dev)
1886{
1887	int error = 0, txq = 0, rxq = 0, real_rx = 0, real_tx = 0;
1888
1889#ifdef CONFIG_SYSFS
1890	dev->queues_kset = kset_create_and_add("queues",
1891					       NULL, &dev->dev.kobj);
1892	if (!dev->queues_kset)
1893		return -ENOMEM;
1894	real_rx = dev->real_num_rx_queues;
1895#endif
1896	real_tx = dev->real_num_tx_queues;
1897
1898	error = net_rx_queue_update_kobjects(dev, 0, real_rx);
 
 
 
 
 
1899	if (error)
1900		goto error;
1901	rxq = real_rx;
1902
1903	error = netdev_queue_update_kobjects(dev, 0, real_tx);
1904	if (error)
1905		goto error;
1906	txq = real_tx;
1907
1908	return 0;
1909
1910error:
1911	netdev_queue_update_kobjects(dev, txq, 0);
1912	net_rx_queue_update_kobjects(dev, rxq, 0);
1913#ifdef CONFIG_SYSFS
1914	kset_unregister(dev->queues_kset);
1915#endif
1916	return error;
1917}
1918
1919static int queue_change_owner(struct net_device *ndev, kuid_t kuid, kgid_t kgid)
1920{
1921	int error = 0, real_rx = 0, real_tx = 0;
1922
1923#ifdef CONFIG_SYSFS
1924	if (ndev->queues_kset) {
1925		error = sysfs_change_owner(&ndev->queues_kset->kobj, kuid, kgid);
1926		if (error)
1927			return error;
1928	}
1929	real_rx = ndev->real_num_rx_queues;
1930#endif
1931	real_tx = ndev->real_num_tx_queues;
1932
1933	error = net_rx_queue_change_owner(ndev, real_rx, kuid, kgid);
1934	if (error)
1935		return error;
1936
1937	error = net_tx_queue_change_owner(ndev, real_tx, kuid, kgid);
1938	if (error)
1939		return error;
1940
1941	return 0;
1942}
1943
1944static void remove_queue_kobjects(struct net_device *dev)
1945{
1946	int real_rx = 0, real_tx = 0;
1947
1948#ifdef CONFIG_SYSFS
1949	real_rx = dev->real_num_rx_queues;
1950#endif
1951	real_tx = dev->real_num_tx_queues;
1952
1953	net_rx_queue_update_kobjects(dev, real_rx, 0);
1954	netdev_queue_update_kobjects(dev, real_tx, 0);
1955
1956	dev->real_num_rx_queues = 0;
1957	dev->real_num_tx_queues = 0;
1958#ifdef CONFIG_SYSFS
1959	kset_unregister(dev->queues_kset);
1960#endif
1961}
1962
1963static bool net_current_may_mount(void)
1964{
1965	struct net *net = current->nsproxy->net_ns;
1966
1967	return ns_capable(net->user_ns, CAP_SYS_ADMIN);
1968}
1969
1970static void *net_grab_current_ns(void)
1971{
1972	struct net *ns = current->nsproxy->net_ns;
1973#ifdef CONFIG_NET_NS
1974	if (ns)
1975		refcount_inc(&ns->passive);
1976#endif
1977	return ns;
1978}
1979
1980static const void *net_initial_ns(void)
1981{
1982	return &init_net;
1983}
1984
1985static const void *net_netlink_ns(struct sock *sk)
1986{
1987	return sock_net(sk);
1988}
1989
1990const struct kobj_ns_type_operations net_ns_type_operations = {
1991	.type = KOBJ_NS_TYPE_NET,
1992	.current_may_mount = net_current_may_mount,
1993	.grab_current_ns = net_grab_current_ns,
1994	.netlink_ns = net_netlink_ns,
1995	.initial_ns = net_initial_ns,
1996	.drop_ns = net_drop_ns,
1997};
1998EXPORT_SYMBOL_GPL(net_ns_type_operations);
1999
2000static int netdev_uevent(const struct device *d, struct kobj_uevent_env *env)
 
2001{
2002	const struct net_device *dev = to_net_dev(d);
2003	int retval;
2004
2005	/* pass interface to uevent. */
2006	retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
2007	if (retval)
2008		goto exit;
2009
2010	/* pass ifindex to uevent.
2011	 * ifindex is useful as it won't change (interface name may change)
2012	 * and is what RtNetlink uses natively.
2013	 */
2014	retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
2015
2016exit:
2017	return retval;
2018}
 
2019
2020/*
2021 *	netdev_release -- destroy and free a dead device.
2022 *	Called when last reference to device kobject is gone.
2023 */
2024static void netdev_release(struct device *d)
2025{
2026	struct net_device *dev = to_net_dev(d);
2027
2028	BUG_ON(dev->reg_state != NETREG_RELEASED);
2029
2030	/* no need to wait for rcu grace period:
2031	 * device is dead and about to be freed.
2032	 */
2033	kfree(rcu_access_pointer(dev->ifalias));
2034	kvfree(dev);
2035}
2036
2037static const void *net_namespace(const struct device *d)
2038{
2039	const struct net_device *dev = to_net_dev(d);
2040
2041	return dev_net(dev);
2042}
2043
2044static void net_get_ownership(const struct device *d, kuid_t *uid, kgid_t *gid)
2045{
2046	const struct net_device *dev = to_net_dev(d);
2047	const struct net *net = dev_net(dev);
2048
2049	net_ns_get_ownership(net, uid, gid);
2050}
2051
2052static const struct class net_class = {
2053	.name = "net",
2054	.dev_release = netdev_release,
2055	.dev_groups = net_class_groups,
 
 
 
2056	.dev_uevent = netdev_uevent,
 
2057	.ns_type = &net_ns_type_operations,
2058	.namespace = net_namespace,
2059	.get_ownership = net_get_ownership,
2060};
2061
2062#ifdef CONFIG_OF
2063static int of_dev_node_match(struct device *dev, const void *data)
2064{
2065	for (; dev; dev = dev->parent) {
2066		if (dev->of_node == data)
2067			return 1;
2068	}
2069
2070	return 0;
2071}
2072
2073/*
2074 * of_find_net_device_by_node - lookup the net device for the device node
2075 * @np: OF device node
2076 *
2077 * Looks up the net_device structure corresponding with the device node.
2078 * If successful, returns a pointer to the net_device with the embedded
2079 * struct device refcount incremented by one, or NULL on failure. The
2080 * refcount must be dropped when done with the net_device.
2081 */
2082struct net_device *of_find_net_device_by_node(struct device_node *np)
2083{
2084	struct device *dev;
2085
2086	dev = class_find_device(&net_class, NULL, np, of_dev_node_match);
2087	if (!dev)
2088		return NULL;
2089
2090	return to_net_dev(dev);
2091}
2092EXPORT_SYMBOL(of_find_net_device_by_node);
2093#endif
2094
2095/* Delete sysfs entries but hold kobject reference until after all
2096 * netdev references are gone.
2097 */
2098void netdev_unregister_kobject(struct net_device *ndev)
2099{
2100	struct device *dev = &ndev->dev;
2101
2102	if (!refcount_read(&dev_net(ndev)->ns.count))
2103		dev_set_uevent_suppress(dev, 1);
2104
2105	kobject_get(&dev->kobj);
2106
2107	remove_queue_kobjects(ndev);
2108
2109	pm_runtime_set_memalloc_noio(dev, false);
2110
2111	device_del(dev);
2112}
2113
2114/* Create sysfs entries for network device. */
2115int netdev_register_kobject(struct net_device *ndev)
2116{
2117	struct device *dev = &ndev->dev;
2118	const struct attribute_group **groups = ndev->sysfs_groups;
2119	int error = 0;
2120
2121	device_initialize(dev);
2122	dev->class = &net_class;
2123	dev->platform_data = ndev;
2124	dev->groups = groups;
2125
2126	dev_set_name(dev, "%s", ndev->name);
2127
2128#ifdef CONFIG_SYSFS
2129	/* Allow for a device specific group */
2130	if (*groups)
2131		groups++;
2132
2133	*groups++ = &netstat_group;
2134
2135	if (wireless_group_needed(ndev))
 
 
 
2136		*groups++ = &wireless_group;
 
 
2137#endif /* CONFIG_SYSFS */
2138
2139	error = device_add(dev);
2140	if (error)
2141		return error;
2142
2143	error = register_queue_kobjects(ndev);
2144	if (error) {
2145		device_del(dev);
2146		return error;
2147	}
2148
2149	pm_runtime_set_memalloc_noio(dev, true);
2150
2151	return error;
2152}
2153
2154/* Change owner for sysfs entries when moving network devices across network
2155 * namespaces owned by different user namespaces.
2156 */
2157int netdev_change_owner(struct net_device *ndev, const struct net *net_old,
2158			const struct net *net_new)
2159{
2160	kuid_t old_uid = GLOBAL_ROOT_UID, new_uid = GLOBAL_ROOT_UID;
2161	kgid_t old_gid = GLOBAL_ROOT_GID, new_gid = GLOBAL_ROOT_GID;
2162	struct device *dev = &ndev->dev;
2163	int error;
2164
2165	net_ns_get_ownership(net_old, &old_uid, &old_gid);
2166	net_ns_get_ownership(net_new, &new_uid, &new_gid);
2167
2168	/* The network namespace was changed but the owning user namespace is
2169	 * identical so there's no need to change the owner of sysfs entries.
2170	 */
2171	if (uid_eq(old_uid, new_uid) && gid_eq(old_gid, new_gid))
2172		return 0;
2173
2174	error = device_change_owner(dev, new_uid, new_gid);
2175	if (error)
2176		return error;
2177
2178	error = queue_change_owner(ndev, new_uid, new_gid);
2179	if (error)
2180		return error;
2181
2182	return 0;
2183}
2184
2185int netdev_class_create_file_ns(const struct class_attribute *class_attr,
2186				const void *ns)
2187{
2188	return class_create_file_ns(&net_class, class_attr, ns);
2189}
2190EXPORT_SYMBOL(netdev_class_create_file_ns);
2191
2192void netdev_class_remove_file_ns(const struct class_attribute *class_attr,
2193				 const void *ns)
2194{
2195	class_remove_file_ns(&net_class, class_attr, ns);
2196}
2197EXPORT_SYMBOL(netdev_class_remove_file_ns);
2198
2199int __init netdev_kobject_init(void)
2200{
2201	kobj_ns_type_register(&net_ns_type_operations);
2202	return class_register(&net_class);
2203}