net/core/net-sysfs.c

   1 /*
   2  * net-sysfs.c - network device class and attributes
   3  *
   4  * Copyright (c) 2003 Stephen Hemminger <shemminger@osdl.org>
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License
   8  *      as published by the Free Software Foundation; either version
   9  *      2 of the License, or (at your option) any later version.
  10  */
  11
  12 #include <linux/capability.h>
  13 #include <linux/kernel.h>
  14 #include <linux/netdevice.h>
  15 #include <net/switchdev.h>
  16 #include <linux/if_arp.h>
  17 #include <linux/slab.h>
  18 #include <linux/nsproxy.h>
  19 #include <net/sock.h>
  20 #include <net/net_namespace.h>
  21 #include <linux/rtnetlink.h>
  22 #include <linux/vmalloc.h>
  23 #include <linux/export.h>
  24 #include <linux/jiffies.h>
  25 #include <linux/pm_runtime.h>
  26
  27 #include "net-sysfs.h"
  28
  29 #ifdef CONFIG_SYSFS
  30 static const char fmt_hex[] = "%#x\n";
  31 static const char fmt_long_hex[] = "%#lx\n";
  32 static const char fmt_dec[] = "%d\n";
  33 static const char fmt_udec[] = "%u\n";
  34 static const char fmt_ulong[] = "%lu\n";
  35 static const char fmt_u64[] = "%llu\n";
  36
  37 static inline int dev_isalive(const struct net_device *dev)
  38 {
  39         return dev->reg_state <= NETREG_REGISTERED;
  40 }
  41
  42 /* use same locking rules as GIF* ioctl's */
  43 static ssize_t netdev_show(const struct device *dev,
  44                            struct device_attribute *attr, char *buf,
  45                            ssize_t (*format)(const struct net_device *, char *))
  46 {
  47         struct net_device *ndev = to_net_dev(dev);
  48         ssize_t ret = -EINVAL;
  49
  50         read_lock(&dev_base_lock);
  51         if (dev_isalive(ndev))
  52                 ret = (*format)(ndev, buf);
  53         read_unlock(&dev_base_lock);
  54
  55         return ret;
  56 }
  57
  58 /* generate a show function for simple field */
  59 #define NETDEVICE_SHOW(field, format_string)                            \
  60 static ssize_t format_##field(const struct net_device *dev, char *buf)  \
  61 {                                                                       \
  62         return sprintf(buf, format_string, dev->field);                 \
  63 }                                                                       \
  64 static ssize_t field##_show(struct device *dev,                         \
  65                             struct device_attribute *attr, char *buf)   \
  66 {                                                                       \
  67         return netdev_show(dev, attr, buf, format_##field);             \
  68 }                                                                       \
  69
  70 #define NETDEVICE_SHOW_RO(field, format_string)                         \
  71 NETDEVICE_SHOW(field, format_string);                                   \
  72 static DEVICE_ATTR_RO(field)
  73
  74 #define NETDEVICE_SHOW_RW(field, format_string)                         \
  75 NETDEVICE_SHOW(field, format_string);                                   \
  76 static DEVICE_ATTR_RW(field)
  77
  78 /* use same locking and permission rules as SIF* ioctl's */
  79 static ssize_t netdev_store(struct device *dev, struct device_attribute *attr,
  80                             const char *buf, size_t len,
  81                             int (*set)(struct net_device *, unsigned long))
  82 {
  83         struct net_device *netdev = to_net_dev(dev);
  84         struct net *net = dev_net(netdev);
  85         unsigned long new;
  86         int ret = -EINVAL;
  87
  88         if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
  89                 return -EPERM;
  90
  91         ret = kstrtoul(buf, 0, &new);
  92         if (ret)
  93                 goto err;
  94
  95         if (!rtnl_trylock())
  96                 return restart_syscall();
  97
  98         if (dev_isalive(netdev)) {
  99                 if ((ret = (*set)(netdev, new)) == 0)
 100                         ret = len;
 101         }
 102         rtnl_unlock();
 103  err:
 104         return ret;
 105 }
 106
 107 NETDEVICE_SHOW_RO(dev_id, fmt_hex);
 108 NETDEVICE_SHOW_RO(dev_port, fmt_dec);
 109 NETDEVICE_SHOW_RO(addr_assign_type, fmt_dec);
 110 NETDEVICE_SHOW_RO(addr_len, fmt_dec);
 111 NETDEVICE_SHOW_RO(iflink, fmt_dec);
 112 NETDEVICE_SHOW_RO(ifindex, fmt_dec);
 113 NETDEVICE_SHOW_RO(type, fmt_dec);
 114 NETDEVICE_SHOW_RO(link_mode, fmt_dec);
 115
 116 static ssize_t format_name_assign_type(const struct net_device *dev, char *buf)
 117 {
 118         return sprintf(buf, fmt_dec, dev->name_assign_type);
 119 }
 120
 121 static ssize_t name_assign_type_show(struct device *dev,
 122                                      struct device_attribute *attr,
 123                                      char *buf)
 124 {
 125         struct net_device *ndev = to_net_dev(dev);
 126         ssize_t ret = -EINVAL;
 127
 128         if (ndev->name_assign_type != NET_NAME_UNKNOWN)
 129                 ret = netdev_show(dev, attr, buf, format_name_assign_type);
 130
 131         return ret;
 132 }
 133 static DEVICE_ATTR_RO(name_assign_type);
 134
 135 /* use same locking rules as GIFHWADDR ioctl's */
 136 static ssize_t address_show(struct device *dev, struct device_attribute *attr,
 137                             char *buf)
 138 {
 139         struct net_device *ndev = to_net_dev(dev);
 140         ssize_t ret = -EINVAL;
 141
 142         read_lock(&dev_base_lock);
 143         if (dev_isalive(ndev))
 144                 ret = sysfs_format_mac(buf, ndev->dev_addr, ndev->addr_len);
 145         read_unlock(&dev_base_lock);
 146         return ret;
 147 }
 148 static DEVICE_ATTR_RO(address);
 149
 150 static ssize_t broadcast_show(struct device *dev,
 151                               struct device_attribute *attr, char *buf)
 152 {
 153         struct net_device *ndev = to_net_dev(dev);
 154         if (dev_isalive(ndev))
 155                 return sysfs_format_mac(buf, ndev->broadcast, ndev->addr_len);
 156         return -EINVAL;
 157 }
 158 static DEVICE_ATTR_RO(broadcast);
 159
 160 static int change_carrier(struct net_device *dev, unsigned long new_carrier)
 161 {
 162         if (!netif_running(dev))
 163                 return -EINVAL;
 164         return dev_change_carrier(dev, (bool) new_carrier);
 165 }
 166
 167 static ssize_t carrier_store(struct device *dev, struct device_attribute *attr,
 168                              const char *buf, size_t len)
 169 {
 170         return netdev_store(dev, attr, buf, len, change_carrier);
 171 }
 172
 173 static ssize_t carrier_show(struct device *dev,
 174                             struct device_attribute *attr, char *buf)
 175 {
 176         struct net_device *netdev = to_net_dev(dev);
 177         if (netif_running(netdev)) {
 178                 return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
 179         }
 180         return -EINVAL;
 181 }
 182 static DEVICE_ATTR_RW(carrier);
 183
 184 static ssize_t speed_show(struct device *dev,
 185                           struct device_attribute *attr, char *buf)
 186 {
 187         struct net_device *netdev = to_net_dev(dev);
 188         int ret = -EINVAL;
 189
 190         if (!rtnl_trylock())
 191                 return restart_syscall();
 192
 193         if (netif_running(netdev)) {
 194                 struct ethtool_cmd cmd;
 195                 if (!__ethtool_get_settings(netdev, &cmd))
 196                         ret = sprintf(buf, fmt_udec, ethtool_cmd_speed(&cmd));
 197         }
 198         rtnl_unlock();
 199         return ret;
 200 }
 201 static DEVICE_ATTR_RO(speed);
 202
 203 static ssize_t duplex_show(struct device *dev,
 204                            struct device_attribute *attr, char *buf)
 205 {
 206         struct net_device *netdev = to_net_dev(dev);
 207         int ret = -EINVAL;
 208
 209         if (!rtnl_trylock())
 210                 return restart_syscall();
 211
 212         if (netif_running(netdev)) {
 213                 struct ethtool_cmd cmd;
 214                 if (!__ethtool_get_settings(netdev, &cmd)) {
 215                         const char *duplex;
 216                         switch (cmd.duplex) {
 217                         case DUPLEX_HALF:
 218                                 duplex = "half";
 219                                 break;
 220                         case DUPLEX_FULL:
 221                                 duplex = "full";
 222                                 break;
 223                         default:
 224                                 duplex = "unknown";
 225                                 break;
 226                         }
 227                         ret = sprintf(buf, "%s\n", duplex);
 228                 }
 229         }
 230         rtnl_unlock();
 231         return ret;
 232 }
 233 static DEVICE_ATTR_RO(duplex);
 234
 235 static ssize_t dormant_show(struct device *dev,
 236                             struct device_attribute *attr, char *buf)
 237 {
 238         struct net_device *netdev = to_net_dev(dev);
 239
 240         if (netif_running(netdev))
 241                 return sprintf(buf, fmt_dec, !!netif_dormant(netdev));
 242
 243         return -EINVAL;
 244 }
 245 static DEVICE_ATTR_RO(dormant);
 246
 247 static const char *const operstates[] = {
 248         "unknown",
 249         "notpresent", /* currently unused */
 250         "down",
 251         "lowerlayerdown",
 252         "testing", /* currently unused */
 253         "dormant",
 254         "up"
 255 };
 256
 257 static ssize_t operstate_show(struct device *dev,
 258                               struct device_attribute *attr, char *buf)
 259 {
 260         const struct net_device *netdev = to_net_dev(dev);
 261         unsigned char operstate;
 262
 263         read_lock(&dev_base_lock);
 264         operstate = netdev->operstate;
 265         if (!netif_running(netdev))
 266                 operstate = IF_OPER_DOWN;
 267         read_unlock(&dev_base_lock);
 268
 269         if (operstate >= ARRAY_SIZE(operstates))
 270                 return -EINVAL; /* should not happen */
 271
 272         return sprintf(buf, "%s\n", operstates[operstate]);
 273 }
 274 static DEVICE_ATTR_RO(operstate);
 275
 276 static ssize_t carrier_changes_show(struct device *dev,
 277                                     struct device_attribute *attr,
 278                                     char *buf)
 279 {
 280         struct net_device *netdev = to_net_dev(dev);
 281         return sprintf(buf, fmt_dec,
 282                        atomic_read(&netdev->carrier_changes));
 283 }
 284 static DEVICE_ATTR_RO(carrier_changes);
 285
 286 /* read-write attributes */
 287
 288 static int change_mtu(struct net_device *dev, unsigned long new_mtu)
 289 {
 290         return dev_set_mtu(dev, (int) new_mtu);
 291 }
 292
 293 static ssize_t mtu_store(struct device *dev, struct device_attribute *attr,
 294                          const char *buf, size_t len)
 295 {
 296         return netdev_store(dev, attr, buf, len, change_mtu);
 297 }
 298 NETDEVICE_SHOW_RW(mtu, fmt_dec);
 299
 300 static int change_flags(struct net_device *dev, unsigned long new_flags)
 301 {
 302         return dev_change_flags(dev, (unsigned int) new_flags);
 303 }
 304
 305 static ssize_t flags_store(struct device *dev, struct device_attribute *attr,
 306                            const char *buf, size_t len)
 307 {
 308         return netdev_store(dev, attr, buf, len, change_flags);
 309 }
 310 NETDEVICE_SHOW_RW(flags, fmt_hex);
 311
 312 static int change_tx_queue_len(struct net_device *dev, unsigned long new_len)
 313 {
 314         dev->tx_queue_len = new_len;
 315         return 0;
 316 }
 317
 318 static ssize_t tx_queue_len_store(struct device *dev,
 319                                   struct device_attribute *attr,
 320                                   const char *buf, size_t len)
 321 {
 322         if (!capable(CAP_NET_ADMIN))
 323                 return -EPERM;
 324
 325         return netdev_store(dev, attr, buf, len, change_tx_queue_len);
 326 }
 327 NETDEVICE_SHOW_RW(tx_queue_len, fmt_ulong);
 328
 329 static int change_gro_flush_timeout(struct net_device *dev, unsigned long val)
 330 {
 331         dev->gro_flush_timeout = val;
 332         return 0;
 333 }
 334
 335 static ssize_t gro_flush_timeout_store(struct device *dev,
 336                                   struct device_attribute *attr,
 337                                   const char *buf, size_t len)
 338 {
 339         if (!capable(CAP_NET_ADMIN))
 340                 return -EPERM;
 341
 342         return netdev_store(dev, attr, buf, len, change_gro_flush_timeout);
 343 }
 344 NETDEVICE_SHOW_RW(gro_flush_timeout, fmt_ulong);
 345
 346 static ssize_t ifalias_store(struct device *dev, struct device_attribute *attr,
 347                              const char *buf, size_t len)
 348 {
 349         struct net_device *netdev = to_net_dev(dev);
 350         struct net *net = dev_net(netdev);
 351         size_t count = len;
 352         ssize_t ret;
 353
 354         if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
 355                 return -EPERM;
 356
 357         /* ignore trailing newline */
 358         if (len >  0 && buf[len - 1] == '\n')
 359                 --count;
 360
 361         if (!rtnl_trylock())
 362                 return restart_syscall();
 363         ret = dev_set_alias(netdev, buf, count);
 364         rtnl_unlock();
 365
 366         return ret < 0 ? ret : len;
 367 }
 368
 369 static ssize_t ifalias_show(struct device *dev,
 370                             struct device_attribute *attr, char *buf)
 371 {
 372         const struct net_device *netdev = to_net_dev(dev);
 373         ssize_t ret = 0;
 374
 375         if (!rtnl_trylock())
 376                 return restart_syscall();
 377         if (netdev->ifalias)
 378                 ret = sprintf(buf, "%s\n", netdev->ifalias);
 379         rtnl_unlock();
 380         return ret;
 381 }
 382 static DEVICE_ATTR_RW(ifalias);
 383
 384 static int change_group(struct net_device *dev, unsigned long new_group)
 385 {
 386         dev_set_group(dev, (int) new_group);
 387         return 0;
 388 }
 389
 390 static ssize_t group_store(struct device *dev, struct device_attribute *attr,
 391                            const char *buf, size_t len)
 392 {
 393         return netdev_store(dev, attr, buf, len, change_group);
 394 }
 395 NETDEVICE_SHOW(group, fmt_dec);
 396 static DEVICE_ATTR(netdev_group, S_IRUGO | S_IWUSR, group_show, group_store);
 397
 398 static ssize_t phys_port_id_show(struct device *dev,
 399                                  struct device_attribute *attr, char *buf)
 400 {
 401         struct net_device *netdev = to_net_dev(dev);
 402         ssize_t ret = -EINVAL;
 403
 404         if (!rtnl_trylock())
 405                 return restart_syscall();
 406
 407         if (dev_isalive(netdev)) {
 408                 struct netdev_phys_item_id ppid;
 409
 410                 ret = dev_get_phys_port_id(netdev, &ppid);
 411                 if (!ret)
 412                         ret = sprintf(buf, "%*phN\n", ppid.id_len, ppid.id);
 413         }
 414         rtnl_unlock();
 415
 416         return ret;
 417 }
 418 static DEVICE_ATTR_RO(phys_port_id);
 419
 420 static ssize_t phys_switch_id_show(struct device *dev,
 421                                    struct device_attribute *attr, char *buf)
 422 {
 423         struct net_device *netdev = to_net_dev(dev);
 424         ssize_t ret = -EINVAL;
 425
 426         if (!rtnl_trylock())
 427                 return restart_syscall();
 428
 429         if (dev_isalive(netdev)) {
 430                 struct netdev_phys_item_id ppid;
 431
 432                 ret = netdev_switch_parent_id_get(netdev, &ppid);
 433                 if (!ret)
 434                         ret = sprintf(buf, "%*phN\n", ppid.id_len, ppid.id);
 435         }
 436         rtnl_unlock();
 437
 438         return ret;
 439 }
 440 static DEVICE_ATTR_RO(phys_switch_id);
 441
 442 static struct attribute *net_class_attrs[] = {
 443         &dev_attr_netdev_group.attr,
 444         &dev_attr_type.attr,
 445         &dev_attr_dev_id.attr,
 446         &dev_attr_dev_port.attr,
 447         &dev_attr_iflink.attr,
 448         &dev_attr_ifindex.attr,
 449         &dev_attr_name_assign_type.attr,
 450         &dev_attr_addr_assign_type.attr,
 451         &dev_attr_addr_len.attr,
 452         &dev_attr_link_mode.attr,
 453         &dev_attr_address.attr,
 454         &dev_attr_broadcast.attr,
 455         &dev_attr_speed.attr,
 456         &dev_attr_duplex.attr,
 457         &dev_attr_dormant.attr,
 458         &dev_attr_operstate.attr,
 459         &dev_attr_carrier_changes.attr,
 460         &dev_attr_ifalias.attr,
 461         &dev_attr_carrier.attr,
 462         &dev_attr_mtu.attr,
 463         &dev_attr_flags.attr,
 464         &dev_attr_tx_queue_len.attr,
 465         &dev_attr_gro_flush_timeout.attr,
 466         &dev_attr_phys_port_id.attr,
 467         &dev_attr_phys_switch_id.attr,
 468         NULL,
 469 };
 470 ATTRIBUTE_GROUPS(net_class);
 471
 472 /* Show a given an attribute in the statistics group */
 473 static ssize_t netstat_show(const struct device *d,
 474                             struct device_attribute *attr, char *buf,
 475                             unsigned long offset)
 476 {
 477         struct net_device *dev = to_net_dev(d);
 478         ssize_t ret = -EINVAL;
 479
 480         WARN_ON(offset > sizeof(struct rtnl_link_stats64) ||
 481                         offset % sizeof(u64) != 0);
 482
 483         read_lock(&dev_base_lock);
 484         if (dev_isalive(dev)) {
 485                 struct rtnl_link_stats64 temp;
 486                 const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp);
 487
 488                 ret = sprintf(buf, fmt_u64, *(u64 *)(((u8 *) stats) + offset));
 489         }
 490         read_unlock(&dev_base_lock);
 491         return ret;
 492 }
 493
 494 /* generate a read-only statistics attribute */
 495 #define NETSTAT_ENTRY(name)                                             \
 496 static ssize_t name##_show(struct device *d,                            \
 497                            struct device_attribute *attr, char *buf)    \
 498 {                                                                       \
 499         return netstat_show(d, attr, buf,                               \
 500                             offsetof(struct rtnl_link_stats64, name));  \
 501 }                                                                       \
 502 static DEVICE_ATTR_RO(name)
 503
 504 NETSTAT_ENTRY(rx_packets);
 505 NETSTAT_ENTRY(tx_packets);
 506 NETSTAT_ENTRY(rx_bytes);
 507 NETSTAT_ENTRY(tx_bytes);
 508 NETSTAT_ENTRY(rx_errors);
 509 NETSTAT_ENTRY(tx_errors);
 510 NETSTAT_ENTRY(rx_dropped);
 511 NETSTAT_ENTRY(tx_dropped);
 512 NETSTAT_ENTRY(multicast);
 513 NETSTAT_ENTRY(collisions);
 514 NETSTAT_ENTRY(rx_length_errors);
 515 NETSTAT_ENTRY(rx_over_errors);
 516 NETSTAT_ENTRY(rx_crc_errors);
 517 NETSTAT_ENTRY(rx_frame_errors);
 518 NETSTAT_ENTRY(rx_fifo_errors);
 519 NETSTAT_ENTRY(rx_missed_errors);
 520 NETSTAT_ENTRY(tx_aborted_errors);
 521 NETSTAT_ENTRY(tx_carrier_errors);
 522 NETSTAT_ENTRY(tx_fifo_errors);
 523 NETSTAT_ENTRY(tx_heartbeat_errors);
 524 NETSTAT_ENTRY(tx_window_errors);
 525 NETSTAT_ENTRY(rx_compressed);
 526 NETSTAT_ENTRY(tx_compressed);
 527
 528 static struct attribute *netstat_attrs[] = {
 529         &dev_attr_rx_packets.attr,
 530         &dev_attr_tx_packets.attr,
 531         &dev_attr_rx_bytes.attr,
 532         &dev_attr_tx_bytes.attr,
 533         &dev_attr_rx_errors.attr,
 534         &dev_attr_tx_errors.attr,
 535         &dev_attr_rx_dropped.attr,
 536         &dev_attr_tx_dropped.attr,
 537         &dev_attr_multicast.attr,
 538         &dev_attr_collisions.attr,
 539         &dev_attr_rx_length_errors.attr,
 540         &dev_attr_rx_over_errors.attr,
 541         &dev_attr_rx_crc_errors.attr,
 542         &dev_attr_rx_frame_errors.attr,
 543         &dev_attr_rx_fifo_errors.attr,
 544         &dev_attr_rx_missed_errors.attr,
 545         &dev_attr_tx_aborted_errors.attr,
 546         &dev_attr_tx_carrier_errors.attr,
 547         &dev_attr_tx_fifo_errors.attr,
 548         &dev_attr_tx_heartbeat_errors.attr,
 549         &dev_attr_tx_window_errors.attr,
 550         &dev_attr_rx_compressed.attr,
 551         &dev_attr_tx_compressed.attr,
 552         NULL
 553 };
 554
 555
 556 static struct attribute_group netstat_group = {
 557         .name  = "statistics",
 558         .attrs  = netstat_attrs,
 559 };
 560
 561 #if IS_ENABLED(CONFIG_WIRELESS_EXT) || IS_ENABLED(CONFIG_CFG80211)
 562 static struct attribute *wireless_attrs[] = {
 563         NULL
 564 };
 565
 566 static struct attribute_group wireless_group = {
 567         .name = "wireless",
 568         .attrs = wireless_attrs,
 569 };
 570 #endif
 571
 572 #else /* CONFIG_SYSFS */
 573 #define net_class_groups        NULL
 574 #endif /* CONFIG_SYSFS */
 575
 576 #ifdef CONFIG_SYSFS
 577 #define to_rx_queue_attr(_attr) container_of(_attr,             \
 578     struct rx_queue_attribute, attr)
 579
 580 #define to_rx_queue(obj) container_of(obj, struct netdev_rx_queue, kobj)
 581
 582 static ssize_t rx_queue_attr_show(struct kobject *kobj, struct attribute *attr,
 583                                   char *buf)
 584 {
 585         struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
 586         struct netdev_rx_queue *queue = to_rx_queue(kobj);
 587
 588         if (!attribute->show)
 589                 return -EIO;
 590
 591         return attribute->show(queue, attribute, buf);
 592 }
 593
 594 static ssize_t rx_queue_attr_store(struct kobject *kobj, struct attribute *attr,
 595                                    const char *buf, size_t count)
 596 {
 597         struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
 598         struct netdev_rx_queue *queue = to_rx_queue(kobj);
 599
 600         if (!attribute->store)
 601                 return -EIO;
 602
 603         return attribute->store(queue, attribute, buf, count);
 604 }
 605
 606 static const struct sysfs_ops rx_queue_sysfs_ops = {
 607         .show = rx_queue_attr_show,
 608         .store = rx_queue_attr_store,
 609 };
 610
 611 #ifdef CONFIG_RPS
 612 static ssize_t show_rps_map(struct netdev_rx_queue *queue,
 613                             struct rx_queue_attribute *attribute, char *buf)
 614 {
 615         struct rps_map *map;
 616         cpumask_var_t mask;
 617         int i, len;
 618
 619         if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
 620                 return -ENOMEM;
 621
 622         rcu_read_lock();
 623         map = rcu_dereference(queue->rps_map);
 624         if (map)
 625                 for (i = 0; i < map->len; i++)
 626                         cpumask_set_cpu(map->cpus[i], mask);
 627
 628         len = snprintf(buf, PAGE_SIZE, "%*pb\n", cpumask_pr_args(mask));
 629         rcu_read_unlock();
 630         free_cpumask_var(mask);
 631
 632         return len < PAGE_SIZE ? len : -EINVAL;
 633 }
 634
 635 static ssize_t store_rps_map(struct netdev_rx_queue *queue,
 636                       struct rx_queue_attribute *attribute,
 637                       const char *buf, size_t len)
 638 {
 639         struct rps_map *old_map, *map;
 640         cpumask_var_t mask;
 641         int err, cpu, i;
 642         static DEFINE_SPINLOCK(rps_map_lock);
 643
 644         if (!capable(CAP_NET_ADMIN))
 645                 return -EPERM;
 646
 647         if (!alloc_cpumask_var(&mask, GFP_KERNEL))
 648                 return -ENOMEM;
 649
 650         err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
 651         if (err) {
 652                 free_cpumask_var(mask);
 653                 return err;
 654         }
 655
 656         map = kzalloc(max_t(unsigned int,
 657             RPS_MAP_SIZE(cpumask_weight(mask)), L1_CACHE_BYTES),
 658             GFP_KERNEL);
 659         if (!map) {
 660                 free_cpumask_var(mask);
 661                 return -ENOMEM;
 662         }
 663
 664         i = 0;
 665         for_each_cpu_and(cpu, mask, cpu_online_mask)
 666                 map->cpus[i++] = cpu;
 667
 668         if (i)
 669                 map->len = i;
 670         else {
 671                 kfree(map);
 672                 map = NULL;
 673         }
 674
 675         spin_lock(&rps_map_lock);
 676         old_map = rcu_dereference_protected(queue->rps_map,
 677                                             lockdep_is_held(&rps_map_lock));
 678         rcu_assign_pointer(queue->rps_map, map);
 679         spin_unlock(&rps_map_lock);
 680
 681         if (map)
 682                 static_key_slow_inc(&rps_needed);
 683         if (old_map) {
 684                 kfree_rcu(old_map, rcu);
 685                 static_key_slow_dec(&rps_needed);
 686         }
 687         free_cpumask_var(mask);
 688         return len;
 689 }
 690
 691 static ssize_t show_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
 692                                            struct rx_queue_attribute *attr,
 693                                            char *buf)
 694 {
 695         struct rps_dev_flow_table *flow_table;
 696         unsigned long val = 0;
 697
 698         rcu_read_lock();
 699         flow_table = rcu_dereference(queue->rps_flow_table);
 700         if (flow_table)
 701                 val = (unsigned long)flow_table->mask + 1;
 702         rcu_read_unlock();
 703
 704         return sprintf(buf, "%lu\n", val);
 705 }
 706
 707 static void rps_dev_flow_table_release(struct rcu_head *rcu)
 708 {
 709         struct rps_dev_flow_table *table = container_of(rcu,
 710             struct rps_dev_flow_table, rcu);
 711         vfree(table);
 712 }
 713
 714 static ssize_t store_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
 715                                      struct rx_queue_attribute *attr,
 716                                      const char *buf, size_t len)
 717 {
 718         unsigned long mask, count;
 719         struct rps_dev_flow_table *table, *old_table;
 720         static DEFINE_SPINLOCK(rps_dev_flow_lock);
 721         int rc;
 722
 723         if (!capable(CAP_NET_ADMIN))
 724                 return -EPERM;
 725
 726         rc = kstrtoul(buf, 0, &count);
 727         if (rc < 0)
 728                 return rc;
 729
 730         if (count) {
 731                 mask = count - 1;
 732                 /* mask = roundup_pow_of_two(count) - 1;
 733                  * without overflows...
 734                  */
 735                 while ((mask | (mask >> 1)) != mask)
 736                         mask |= (mask >> 1);
 737                 /* On 64 bit arches, must check mask fits in table->mask (u32),
 738                  * and on 32bit arches, must check
 739                  * RPS_DEV_FLOW_TABLE_SIZE(mask + 1) doesn't overflow.
 740                  */
 741 #if BITS_PER_LONG > 32
 742                 if (mask > (unsigned long)(u32)mask)
 743                         return -EINVAL;
 744 #else
 745                 if (mask > (ULONG_MAX - RPS_DEV_FLOW_TABLE_SIZE(1))
 746                                 / sizeof(struct rps_dev_flow)) {
 747                         /* Enforce a limit to prevent overflow */
 748                         return -EINVAL;
 749                 }
 750 #endif
 751                 table = vmalloc(RPS_DEV_FLOW_TABLE_SIZE(mask + 1));
 752                 if (!table)
 753                         return -ENOMEM;
 754
 755                 table->mask = mask;
 756                 for (count = 0; count <= mask; count++)
 757                         table->flows[count].cpu = RPS_NO_CPU;
 758         } else
 759                 table = NULL;
 760
 761         spin_lock(&rps_dev_flow_lock);
 762         old_table = rcu_dereference_protected(queue->rps_flow_table,
 763                                               lockdep_is_held(&rps_dev_flow_lock));
 764         rcu_assign_pointer(queue->rps_flow_table, table);
 765         spin_unlock(&rps_dev_flow_lock);
 766
 767         if (old_table)
 768                 call_rcu(&old_table->rcu, rps_dev_flow_table_release);
 769
 770         return len;
 771 }
 772
 773 static struct rx_queue_attribute rps_cpus_attribute =
 774         __ATTR(rps_cpus, S_IRUGO | S_IWUSR, show_rps_map, store_rps_map);
 775
 776
 777 static struct rx_queue_attribute rps_dev_flow_table_cnt_attribute =
 778         __ATTR(rps_flow_cnt, S_IRUGO | S_IWUSR,
 779             show_rps_dev_flow_table_cnt, store_rps_dev_flow_table_cnt);
 780 #endif /* CONFIG_RPS */
 781
 782 static struct attribute *rx_queue_default_attrs[] = {
 783 #ifdef CONFIG_RPS
 784         &rps_cpus_attribute.attr,
 785         &rps_dev_flow_table_cnt_attribute.attr,
 786 #endif
 787         NULL
 788 };
 789
 790 static void rx_queue_release(struct kobject *kobj)
 791 {
 792         struct netdev_rx_queue *queue = to_rx_queue(kobj);
 793 #ifdef CONFIG_RPS
 794         struct rps_map *map;
 795         struct rps_dev_flow_table *flow_table;
 796
 797
 798         map = rcu_dereference_protected(queue->rps_map, 1);
 799         if (map) {
 800                 RCU_INIT_POINTER(queue->rps_map, NULL);
 801                 kfree_rcu(map, rcu);
 802         }
 803
 804         flow_table = rcu_dereference_protected(queue->rps_flow_table, 1);
 805         if (flow_table) {
 806                 RCU_INIT_POINTER(queue->rps_flow_table, NULL);
 807                 call_rcu(&flow_table->rcu, rps_dev_flow_table_release);
 808         }
 809 #endif
 810
 811         memset(kobj, 0, sizeof(*kobj));
 812         dev_put(queue->dev);
 813 }
 814
 815 static const void *rx_queue_namespace(struct kobject *kobj)
 816 {
 817         struct netdev_rx_queue *queue = to_rx_queue(kobj);
 818         struct device *dev = &queue->dev->dev;
 819         const void *ns = NULL;
 820
 821         if (dev->class && dev->class->ns_type)
 822                 ns = dev->class->namespace(dev);
 823
 824         return ns;
 825 }
 826
 827 static struct kobj_type rx_queue_ktype = {
 828         .sysfs_ops = &rx_queue_sysfs_ops,
 829         .release = rx_queue_release,
 830         .default_attrs = rx_queue_default_attrs,
 831         .namespace = rx_queue_namespace
 832 };
 833
 834 static int rx_queue_add_kobject(struct net_device *dev, int index)
 835 {
 836         struct netdev_rx_queue *queue = dev->_rx + index;
 837         struct kobject *kobj = &queue->kobj;
 838         int error = 0;
 839
 840         kobj->kset = dev->queues_kset;
 841         error = kobject_init_and_add(kobj, &rx_queue_ktype, NULL,
 842             "rx-%u", index);
 843         if (error)
 844                 goto exit;
 845
 846         if (dev->sysfs_rx_queue_group) {
 847                 error = sysfs_create_group(kobj, dev->sysfs_rx_queue_group);
 848                 if (error)
 849                         goto exit;
 850         }
 851
 852         kobject_uevent(kobj, KOBJ_ADD);
 853         dev_hold(queue->dev);
 854
 855         return error;
 856 exit:
 857         kobject_put(kobj);
 858         return error;
 859 }
 860 #endif /* CONFIG_SYSFS */
 861
 862 int
 863 net_rx_queue_update_kobjects(struct net_device *dev, int old_num, int new_num)
 864 {
 865 #ifdef CONFIG_SYSFS
 866         int i;
 867         int error = 0;
 868
 869 #ifndef CONFIG_RPS
 870         if (!dev->sysfs_rx_queue_group)
 871                 return 0;
 872 #endif
 873         for (i = old_num; i < new_num; i++) {
 874                 error = rx_queue_add_kobject(dev, i);
 875                 if (error) {
 876                         new_num = old_num;
 877                         break;
 878                 }
 879         }
 880
 881         while (--i >= new_num) {
 882                 if (dev->sysfs_rx_queue_group)
 883                         sysfs_remove_group(&dev->_rx[i].kobj,
 884                                            dev->sysfs_rx_queue_group);
 885                 kobject_put(&dev->_rx[i].kobj);
 886         }
 887
 888         return error;
 889 #else
 890         return 0;
 891 #endif
 892 }
 893
 894 #ifdef CONFIG_SYSFS
 895 /*
 896  * netdev_queue sysfs structures and functions.
 897  */
 898 struct netdev_queue_attribute {
 899         struct attribute attr;
 900         ssize_t (*show)(struct netdev_queue *queue,
 901             struct netdev_queue_attribute *attr, char *buf);
 902         ssize_t (*store)(struct netdev_queue *queue,
 903             struct netdev_queue_attribute *attr, const char *buf, size_t len);
 904 };
 905 #define to_netdev_queue_attr(_attr) container_of(_attr,         \
 906     struct netdev_queue_attribute, attr)
 907
 908 #define to_netdev_queue(obj) container_of(obj, struct netdev_queue, kobj)
 909
 910 static ssize_t netdev_queue_attr_show(struct kobject *kobj,
 911                                       struct attribute *attr, char *buf)
 912 {
 913         struct netdev_queue_attribute *attribute = to_netdev_queue_attr(attr);
 914         struct netdev_queue *queue = to_netdev_queue(kobj);
 915
 916         if (!attribute->show)
 917                 return -EIO;
 918
 919         return attribute->show(queue, attribute, buf);
 920 }
 921
 922 static ssize_t netdev_queue_attr_store(struct kobject *kobj,
 923                                        struct attribute *attr,
 924                                        const char *buf, size_t count)
 925 {
 926         struct netdev_queue_attribute *attribute = to_netdev_queue_attr(attr);
 927         struct netdev_queue *queue = to_netdev_queue(kobj);
 928
 929         if (!attribute->store)
 930                 return -EIO;
 931
 932         return attribute->store(queue, attribute, buf, count);
 933 }
 934
 935 static const struct sysfs_ops netdev_queue_sysfs_ops = {
 936         .show = netdev_queue_attr_show,
 937         .store = netdev_queue_attr_store,
 938 };
 939
 940 static ssize_t show_trans_timeout(struct netdev_queue *queue,
 941                                   struct netdev_queue_attribute *attribute,
 942                                   char *buf)
 943 {
 944         unsigned long trans_timeout;
 945
 946         spin_lock_irq(&queue->_xmit_lock);
 947         trans_timeout = queue->trans_timeout;
 948         spin_unlock_irq(&queue->_xmit_lock);
 949
 950         return sprintf(buf, "%lu", trans_timeout);
 951 }
 952
 953 static struct netdev_queue_attribute queue_trans_timeout =
 954         __ATTR(tx_timeout, S_IRUGO, show_trans_timeout, NULL);
 955
 956 #ifdef CONFIG_BQL
 957 /*
 958  * Byte queue limits sysfs structures and functions.
 959  */
 960 static ssize_t bql_show(char *buf, unsigned int value)
 961 {
 962         return sprintf(buf, "%u\n", value);
 963 }
 964
 965 static ssize_t bql_set(const char *buf, const size_t count,
 966                        unsigned int *pvalue)
 967 {
 968         unsigned int value;
 969         int err;
 970
 971         if (!strcmp(buf, "max") || !strcmp(buf, "max\n"))
 972                 value = DQL_MAX_LIMIT;
 973         else {
 974                 err = kstrtouint(buf, 10, &value);
 975                 if (err < 0)
 976                         return err;
 977                 if (value > DQL_MAX_LIMIT)
 978                         return -EINVAL;
 979         }
 980
 981         *pvalue = value;
 982
 983         return count;
 984 }
 985
 986 static ssize_t bql_show_hold_time(struct netdev_queue *queue,
 987                                   struct netdev_queue_attribute *attr,
 988                                   char *buf)
 989 {
 990         struct dql *dql = &queue->dql;
 991
 992         return sprintf(buf, "%u\n", jiffies_to_msecs(dql->slack_hold_time));
 993 }
 994
 995 static ssize_t bql_set_hold_time(struct netdev_queue *queue,
 996                                  struct netdev_queue_attribute *attribute,
 997                                  const char *buf, size_t len)
 998 {
 999         struct dql *dql = &queue->dql;
1000         unsigned int value;
1001         int err;
1002
1003         err = kstrtouint(buf, 10, &value);
1004         if (err < 0)
1005                 return err;
1006
1007         dql->slack_hold_time = msecs_to_jiffies(value);
1008
1009         return len;
1010 }
1011
1012 static struct netdev_queue_attribute bql_hold_time_attribute =
1013         __ATTR(hold_time, S_IRUGO | S_IWUSR, bql_show_hold_time,
1014             bql_set_hold_time);
1015
1016 static ssize_t bql_show_inflight(struct netdev_queue *queue,
1017                                  struct netdev_queue_attribute *attr,
1018                                  char *buf)
1019 {
1020         struct dql *dql = &queue->dql;
1021
1022         return sprintf(buf, "%u\n", dql->num_queued - dql->num_completed);
1023 }
1024
1025 static struct netdev_queue_attribute bql_inflight_attribute =
1026         __ATTR(inflight, S_IRUGO, bql_show_inflight, NULL);
1027
1028 #define BQL_ATTR(NAME, FIELD)                                           \
1029 static ssize_t bql_show_ ## NAME(struct netdev_queue *queue,            \
1030                                  struct netdev_queue_attribute *attr,   \
1031                                  char *buf)                             \
1032 {                                                                       \
1033         return bql_show(buf, queue->dql.FIELD);                         \
1034 }                                                                       \
1035                                                                         \
1036 static ssize_t bql_set_ ## NAME(struct netdev_queue *queue,             \
1037                                 struct netdev_queue_attribute *attr,    \
1038                                 const char *buf, size_t len)            \
1039 {                                                                       \
1040         return bql_set(buf, len, &queue->dql.FIELD);                    \
1041 }                                                                       \
1042                                                                         \
1043 static struct netdev_queue_attribute bql_ ## NAME ## _attribute =       \
1044         __ATTR(NAME, S_IRUGO | S_IWUSR, bql_show_ ## NAME,              \
1045             bql_set_ ## NAME);
1046
1047 BQL_ATTR(limit, limit)
1048 BQL_ATTR(limit_max, max_limit)
1049 BQL_ATTR(limit_min, min_limit)
1050
1051 static struct attribute *dql_attrs[] = {
1052         &bql_limit_attribute.attr,
1053         &bql_limit_max_attribute.attr,
1054         &bql_limit_min_attribute.attr,
1055         &bql_hold_time_attribute.attr,
1056         &bql_inflight_attribute.attr,
1057         NULL
1058 };
1059
1060 static struct attribute_group dql_group = {
1061         .name  = "byte_queue_limits",
1062         .attrs  = dql_attrs,
1063 };
1064 #endif /* CONFIG_BQL */
1065
1066 #ifdef CONFIG_XPS
1067 static unsigned int get_netdev_queue_index(struct netdev_queue *queue)
1068 {
1069         struct net_device *dev = queue->dev;
1070         unsigned int i;
1071
1072         i = queue - dev->_tx;
1073         BUG_ON(i >= dev->num_tx_queues);
1074
1075         return i;
1076 }
1077
1078
1079 static ssize_t show_xps_map(struct netdev_queue *queue,
1080                             struct netdev_queue_attribute *attribute, char *buf)
1081 {
1082         struct net_device *dev = queue->dev;
1083         struct xps_dev_maps *dev_maps;
1084         cpumask_var_t mask;
1085         unsigned long index;
1086         int i, len;
1087
1088         if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
1089                 return -ENOMEM;
1090
1091         index = get_netdev_queue_index(queue);
1092
1093         rcu_read_lock();
1094         dev_maps = rcu_dereference(dev->xps_maps);
1095         if (dev_maps) {
1096                 for_each_possible_cpu(i) {
1097                         struct xps_map *map =
1098                             rcu_dereference(dev_maps->cpu_map[i]);
1099                         if (map) {
1100                                 int j;
1101                                 for (j = 0; j < map->len; j++) {
1102                                         if (map->queues[j] == index) {
1103                                                 cpumask_set_cpu(i, mask);
1104                                                 break;
1105                                         }
1106                                 }
1107                         }
1108                 }
1109         }
1110         rcu_read_unlock();
1111
1112         len = snprintf(buf, PAGE_SIZE, "%*pb\n", cpumask_pr_args(mask));
1113         free_cpumask_var(mask);
1114         return len < PAGE_SIZE ? len : -EINVAL;
1115 }
1116
1117 static ssize_t store_xps_map(struct netdev_queue *queue,
1118                       struct netdev_queue_attribute *attribute,
1119                       const char *buf, size_t len)
1120 {
1121         struct net_device *dev = queue->dev;
1122         unsigned long index;
1123         cpumask_var_t mask;
1124         int err;
1125
1126         if (!capable(CAP_NET_ADMIN))
1127                 return -EPERM;
1128
1129         if (!alloc_cpumask_var(&mask, GFP_KERNEL))
1130                 return -ENOMEM;
1131
1132         index = get_netdev_queue_index(queue);
1133
1134         err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
1135         if (err) {
1136                 free_cpumask_var(mask);
1137                 return err;
1138         }
1139
1140         err = netif_set_xps_queue(dev, mask, index);
1141
1142         free_cpumask_var(mask);
1143
1144         return err ? : len;
1145 }
1146
1147 static struct netdev_queue_attribute xps_cpus_attribute =
1148     __ATTR(xps_cpus, S_IRUGO | S_IWUSR, show_xps_map, store_xps_map);
1149 #endif /* CONFIG_XPS */
1150
1151 static struct attribute *netdev_queue_default_attrs[] = {
1152         &queue_trans_timeout.attr,
1153 #ifdef CONFIG_XPS
1154         &xps_cpus_attribute.attr,
1155 #endif
1156         NULL
1157 };
1158
1159 static void netdev_queue_release(struct kobject *kobj)
1160 {
1161         struct netdev_queue *queue = to_netdev_queue(kobj);
1162
1163         memset(kobj, 0, sizeof(*kobj));
1164         dev_put(queue->dev);
1165 }
1166
1167 static const void *netdev_queue_namespace(struct kobject *kobj)
1168 {
1169         struct netdev_queue *queue = to_netdev_queue(kobj);
1170         struct device *dev = &queue->dev->dev;
1171         const void *ns = NULL;
1172
1173         if (dev->class && dev->class->ns_type)
1174                 ns = dev->class->namespace(dev);
1175
1176         return ns;
1177 }
1178
1179 static struct kobj_type netdev_queue_ktype = {
1180         .sysfs_ops = &netdev_queue_sysfs_ops,
1181         .release = netdev_queue_release,
1182         .default_attrs = netdev_queue_default_attrs,
1183         .namespace = netdev_queue_namespace,
1184 };
1185
1186 static int netdev_queue_add_kobject(struct net_device *dev, int index)
1187 {
1188         struct netdev_queue *queue = dev->_tx + index;
1189         struct kobject *kobj = &queue->kobj;
1190         int error = 0;
1191
1192         kobj->kset = dev->queues_kset;
1193         error = kobject_init_and_add(kobj, &netdev_queue_ktype, NULL,
1194             "tx-%u", index);
1195         if (error)
1196                 goto exit;
1197
1198 #ifdef CONFIG_BQL
1199         error = sysfs_create_group(kobj, &dql_group);
1200         if (error)
1201                 goto exit;
1202 #endif
1203
1204         kobject_uevent(kobj, KOBJ_ADD);
1205         dev_hold(queue->dev);
1206
1207         return 0;
1208 exit:
1209         kobject_put(kobj);
1210         return error;
1211 }
1212 #endif /* CONFIG_SYSFS */
1213
1214 int
1215 netdev_queue_update_kobjects(struct net_device *dev, int old_num, int new_num)
1216 {
1217 #ifdef CONFIG_SYSFS
1218         int i;
1219         int error = 0;
1220
1221         for (i = old_num; i < new_num; i++) {
1222                 error = netdev_queue_add_kobject(dev, i);
1223                 if (error) {
1224                         new_num = old_num;
1225                         break;
1226                 }
1227         }
1228
1229         while (--i >= new_num) {
1230                 struct netdev_queue *queue = dev->_tx + i;
1231
1232 #ifdef CONFIG_BQL
1233                 sysfs_remove_group(&queue->kobj, &dql_group);
1234 #endif
1235                 kobject_put(&queue->kobj);
1236         }
1237
1238         return error;
1239 #else
1240         return 0;
1241 #endif /* CONFIG_SYSFS */
1242 }
1243
1244 static int register_queue_kobjects(struct net_device *dev)
1245 {
1246         int error = 0, txq = 0, rxq = 0, real_rx = 0, real_tx = 0;
1247
1248 #ifdef CONFIG_SYSFS
1249         dev->queues_kset = kset_create_and_add("queues",
1250             NULL, &dev->dev.kobj);
1251         if (!dev->queues_kset)
1252                 return -ENOMEM;
1253         real_rx = dev->real_num_rx_queues;
1254 #endif
1255         real_tx = dev->real_num_tx_queues;
1256
1257         error = net_rx_queue_update_kobjects(dev, 0, real_rx);
1258         if (error)
1259                 goto error;
1260         rxq = real_rx;
1261
1262         error = netdev_queue_update_kobjects(dev, 0, real_tx);
1263         if (error)
1264                 goto error;
1265         txq = real_tx;
1266
1267         return 0;
1268
1269 error:
1270         netdev_queue_update_kobjects(dev, txq, 0);
1271         net_rx_queue_update_kobjects(dev, rxq, 0);
1272         return error;
1273 }
1274
1275 static void remove_queue_kobjects(struct net_device *dev)
1276 {
1277         int real_rx = 0, real_tx = 0;
1278
1279 #ifdef CONFIG_SYSFS
1280         real_rx = dev->real_num_rx_queues;
1281 #endif
1282         real_tx = dev->real_num_tx_queues;
1283
1284         net_rx_queue_update_kobjects(dev, real_rx, 0);
1285         netdev_queue_update_kobjects(dev, real_tx, 0);
1286 #ifdef CONFIG_SYSFS
1287         kset_unregister(dev->queues_kset);
1288 #endif
1289 }
1290
1291 static bool net_current_may_mount(void)
1292 {
1293         struct net *net = current->nsproxy->net_ns;
1294
1295         return ns_capable(net->user_ns, CAP_SYS_ADMIN);
1296 }
1297
1298 static void *net_grab_current_ns(void)
1299 {
1300         struct net *ns = current->nsproxy->net_ns;
1301 #ifdef CONFIG_NET_NS
1302         if (ns)
1303                 atomic_inc(&ns->passive);
1304 #endif
1305         return ns;
1306 }
1307
1308 static const void *net_initial_ns(void)
1309 {
1310         return &init_net;
1311 }
1312
1313 static const void *net_netlink_ns(struct sock *sk)
1314 {
1315         return sock_net(sk);
1316 }
1317
1318 struct kobj_ns_type_operations net_ns_type_operations = {
1319         .type = KOBJ_NS_TYPE_NET,
1320         .current_may_mount = net_current_may_mount,
1321         .grab_current_ns = net_grab_current_ns,
1322         .netlink_ns = net_netlink_ns,
1323         .initial_ns = net_initial_ns,
1324         .drop_ns = net_drop_ns,
1325 };
1326 EXPORT_SYMBOL_GPL(net_ns_type_operations);
1327
1328 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
1329 {
1330         struct net_device *dev = to_net_dev(d);
1331         int retval;
1332
1333         /* pass interface to uevent. */
1334         retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
1335         if (retval)
1336                 goto exit;
1337
1338         /* pass ifindex to uevent.
1339          * ifindex is useful as it won't change (interface name may change)
1340          * and is what RtNetlink uses natively. */
1341         retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
1342
1343 exit:
1344         return retval;
1345 }
1346
1347 /*
1348  *      netdev_release -- destroy and free a dead device.
1349  *      Called when last reference to device kobject is gone.
1350  */
1351 static void netdev_release(struct device *d)
1352 {
1353         struct net_device *dev = to_net_dev(d);
1354
1355         BUG_ON(dev->reg_state != NETREG_RELEASED);
1356
1357         kfree(dev->ifalias);
1358         netdev_freemem(dev);
1359 }
1360
1361 static const void *net_namespace(struct device *d)
1362 {
1363         struct net_device *dev;
1364         dev = container_of(d, struct net_device, dev);
1365         return dev_net(dev);
1366 }
1367
1368 static struct class net_class = {
1369         .name = "net",
1370         .dev_release = netdev_release,
1371         .dev_groups = net_class_groups,
1372         .dev_uevent = netdev_uevent,
1373         .ns_type = &net_ns_type_operations,
1374         .namespace = net_namespace,
1375 };
1376
1377 /* Delete sysfs entries but hold kobject reference until after all
1378  * netdev references are gone.
1379  */
1380 void netdev_unregister_kobject(struct net_device *ndev)
1381 {
1382         struct device *dev = &(ndev->dev);
1383
1384         kobject_get(&dev->kobj);
1385
1386         remove_queue_kobjects(ndev);
1387
1388         pm_runtime_set_memalloc_noio(dev, false);
1389
1390         device_del(dev);
1391 }
1392
1393 /* Create sysfs entries for network device. */
1394 int netdev_register_kobject(struct net_device *ndev)
1395 {
1396         struct device *dev = &(ndev->dev);
1397         const struct attribute_group **groups = ndev->sysfs_groups;
1398         int error = 0;
1399
1400         device_initialize(dev);
1401         dev->class = &net_class;
1402         dev->platform_data = ndev;
1403         dev->groups = groups;
1404
1405         dev_set_name(dev, "%s", ndev->name);
1406
1407 #ifdef CONFIG_SYSFS
1408         /* Allow for a device specific group */
1409         if (*groups)
1410                 groups++;
1411
1412         *groups++ = &netstat_group;
1413
1414 #if IS_ENABLED(CONFIG_WIRELESS_EXT) || IS_ENABLED(CONFIG_CFG80211)
1415         if (ndev->ieee80211_ptr)
1416                 *groups++ = &wireless_group;
1417 #if IS_ENABLED(CONFIG_WIRELESS_EXT)
1418         else if (ndev->wireless_handlers)
1419                 *groups++ = &wireless_group;
1420 #endif
1421 #endif
1422 #endif /* CONFIG_SYSFS */
1423
1424         error = device_add(dev);
1425         if (error)
1426                 return error;
1427
1428         error = register_queue_kobjects(ndev);
1429         if (error) {
1430                 device_del(dev);
1431                 return error;
1432         }
1433
1434         pm_runtime_set_memalloc_noio(dev, true);
1435
1436         return error;
1437 }
1438
1439 int netdev_class_create_file_ns(struct class_attribute *class_attr,
1440                                 const void *ns)
1441 {
1442         return class_create_file_ns(&net_class, class_attr, ns);
1443 }
1444 EXPORT_SYMBOL(netdev_class_create_file_ns);
1445
1446 void netdev_class_remove_file_ns(struct class_attribute *class_attr,
1447                                  const void *ns)
1448 {
1449         class_remove_file_ns(&net_class, class_attr, ns);
1450 }
1451 EXPORT_SYMBOL(netdev_class_remove_file_ns);
1452
1453 int __init netdev_kobject_init(void)
1454 {
1455         kobj_ns_type_register(&net_ns_type_operations);
1456         return class_register(&net_class);
1457 }