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