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/wireless.h>
  22 #include <linux/vmalloc.h>
  23 #include <net/wext.h>
  24
  25 #include "net-sysfs.h"
  26
  27 #ifdef CONFIG_SYSFS
  28 static const char fmt_hex[] = "%#x\n";
  29 static const char fmt_long_hex[] = "%#lx\n";
  30 static const char fmt_dec[] = "%d\n";
  31 static const char fmt_udec[] = "%u\n";
  32 static const char fmt_ulong[] = "%lu\n";
  33 static const char fmt_u64[] = "%llu\n";
  34
  35 static inline int dev_isalive(const struct net_device *dev)
  36 {
  37         return dev->reg_state <= NETREG_REGISTERED;
  38 }
  39
  40 /* use same locking rules as GIF* ioctl's */
  41 static ssize_t netdev_show(const struct device *dev,
  42                            struct device_attribute *attr, char *buf,
  43                            ssize_t (*format)(const struct net_device *, char *))
  44 {
  45         struct net_device *net = to_net_dev(dev);
  46         ssize_t ret = -EINVAL;
  47
  48         read_lock(&dev_base_lock);
  49         if (dev_isalive(net))
  50                 ret = (*format)(net, buf);
  51         read_unlock(&dev_base_lock);
  52
  53         return ret;
  54 }
  55
  56 /* generate a show function for simple field */
  57 #define NETDEVICE_SHOW(field, format_string)                            \
  58 static ssize_t format_##field(const struct net_device *net, char *buf)  \
  59 {                                                                       \
  60         return sprintf(buf, format_string, net->field);                 \
  61 }                                                                       \
  62 static ssize_t show_##field(struct device *dev,                         \
  63                             struct device_attribute *attr, char *buf)   \
  64 {                                                                       \
  65         return netdev_show(dev, attr, buf, format_##field);             \
  66 }
  67
  68
  69 /* use same locking and permission rules as SIF* ioctl's */
  70 static ssize_t netdev_store(struct device *dev, struct device_attribute *attr,
  71                             const char *buf, size_t len,
  72                             int (*set)(struct net_device *, unsigned long))
  73 {
  74         struct net_device *net = to_net_dev(dev);
  75         char *endp;
  76         unsigned long new;
  77         int ret = -EINVAL;
  78
  79         if (!capable(CAP_NET_ADMIN))
  80                 return -EPERM;
  81
  82         new = simple_strtoul(buf, &endp, 0);
  83         if (endp == buf)
  84                 goto err;
  85
  86         if (!rtnl_trylock())
  87                 return restart_syscall();
  88
  89         if (dev_isalive(net)) {
  90                 if ((ret = (*set)(net, new)) == 0)
  91                         ret = len;
  92         }
  93         rtnl_unlock();
  94  err:
  95         return ret;
  96 }
  97
  98 NETDEVICE_SHOW(dev_id, fmt_hex);
  99 NETDEVICE_SHOW(addr_assign_type, fmt_dec);
 100 NETDEVICE_SHOW(addr_len, fmt_dec);
 101 NETDEVICE_SHOW(iflink, fmt_dec);
 102 NETDEVICE_SHOW(ifindex, fmt_dec);
 103 NETDEVICE_SHOW(type, fmt_dec);
 104 NETDEVICE_SHOW(link_mode, fmt_dec);
 105
 106 /* use same locking rules as GIFHWADDR ioctl's */
 107 static ssize_t show_address(struct device *dev, struct device_attribute *attr,
 108                             char *buf)
 109 {
 110         struct net_device *net = to_net_dev(dev);
 111         ssize_t ret = -EINVAL;
 112
 113         read_lock(&dev_base_lock);
 114         if (dev_isalive(net))
 115                 ret = sysfs_format_mac(buf, net->dev_addr, net->addr_len);
 116         read_unlock(&dev_base_lock);
 117         return ret;
 118 }
 119
 120 static ssize_t show_broadcast(struct device *dev,
 121                             struct device_attribute *attr, char *buf)
 122 {
 123         struct net_device *net = to_net_dev(dev);
 124         if (dev_isalive(net))
 125                 return sysfs_format_mac(buf, net->broadcast, net->addr_len);
 126         return -EINVAL;
 127 }
 128
 129 static ssize_t show_carrier(struct device *dev,
 130                             struct device_attribute *attr, char *buf)
 131 {
 132         struct net_device *netdev = to_net_dev(dev);
 133         if (netif_running(netdev)) {
 134                 return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
 135         }
 136         return -EINVAL;
 137 }
 138
 139 static ssize_t show_speed(struct device *dev,
 140                           struct device_attribute *attr, char *buf)
 141 {
 142         struct net_device *netdev = to_net_dev(dev);
 143         int ret = -EINVAL;
 144
 145         if (!rtnl_trylock())
 146                 return restart_syscall();
 147
 148         if (netif_running(netdev)) {
 149                 struct ethtool_cmd cmd;
 150                 if (!__ethtool_get_settings(netdev, &cmd))
 151                         ret = sprintf(buf, fmt_udec, ethtool_cmd_speed(&cmd));
 152         }
 153         rtnl_unlock();
 154         return ret;
 155 }
 156
 157 static ssize_t show_duplex(struct device *dev,
 158                            struct device_attribute *attr, char *buf)
 159 {
 160         struct net_device *netdev = to_net_dev(dev);
 161         int ret = -EINVAL;
 162
 163         if (!rtnl_trylock())
 164                 return restart_syscall();
 165
 166         if (netif_running(netdev)) {
 167                 struct ethtool_cmd cmd;
 168                 if (!__ethtool_get_settings(netdev, &cmd))
 169                         ret = sprintf(buf, "%s\n",
 170                                       cmd.duplex ? "full" : "half");
 171         }
 172         rtnl_unlock();
 173         return ret;
 174 }
 175
 176 static ssize_t show_dormant(struct device *dev,
 177                             struct device_attribute *attr, char *buf)
 178 {
 179         struct net_device *netdev = to_net_dev(dev);
 180
 181         if (netif_running(netdev))
 182                 return sprintf(buf, fmt_dec, !!netif_dormant(netdev));
 183
 184         return -EINVAL;
 185 }
 186
 187 static const char *const operstates[] = {
 188         "unknown",
 189         "notpresent", /* currently unused */
 190         "down",
 191         "lowerlayerdown",
 192         "testing", /* currently unused */
 193         "dormant",
 194         "up"
 195 };
 196
 197 static ssize_t show_operstate(struct device *dev,
 198                               struct device_attribute *attr, char *buf)
 199 {
 200         const struct net_device *netdev = to_net_dev(dev);
 201         unsigned char operstate;
 202
 203         read_lock(&dev_base_lock);
 204         operstate = netdev->operstate;
 205         if (!netif_running(netdev))
 206                 operstate = IF_OPER_DOWN;
 207         read_unlock(&dev_base_lock);
 208
 209         if (operstate >= ARRAY_SIZE(operstates))
 210                 return -EINVAL; /* should not happen */
 211
 212         return sprintf(buf, "%s\n", operstates[operstate]);
 213 }
 214
 215 /* read-write attributes */
 216 NETDEVICE_SHOW(mtu, fmt_dec);
 217
 218 static int change_mtu(struct net_device *net, unsigned long new_mtu)
 219 {
 220         return dev_set_mtu(net, (int) new_mtu);
 221 }
 222
 223 static ssize_t store_mtu(struct device *dev, struct device_attribute *attr,
 224                          const char *buf, size_t len)
 225 {
 226         return netdev_store(dev, attr, buf, len, change_mtu);
 227 }
 228
 229 NETDEVICE_SHOW(flags, fmt_hex);
 230
 231 static int change_flags(struct net_device *net, unsigned long new_flags)
 232 {
 233         return dev_change_flags(net, (unsigned) new_flags);
 234 }
 235
 236 static ssize_t store_flags(struct device *dev, struct device_attribute *attr,
 237                            const char *buf, size_t len)
 238 {
 239         return netdev_store(dev, attr, buf, len, change_flags);
 240 }
 241
 242 NETDEVICE_SHOW(tx_queue_len, fmt_ulong);
 243
 244 static int change_tx_queue_len(struct net_device *net, unsigned long new_len)
 245 {
 246         net->tx_queue_len = new_len;
 247         return 0;
 248 }
 249
 250 static ssize_t store_tx_queue_len(struct device *dev,
 251                                   struct device_attribute *attr,
 252                                   const char *buf, size_t len)
 253 {
 254         return netdev_store(dev, attr, buf, len, change_tx_queue_len);
 255 }
 256
 257 static ssize_t store_ifalias(struct device *dev, struct device_attribute *attr,
 258                              const char *buf, size_t len)
 259 {
 260         struct net_device *netdev = to_net_dev(dev);
 261         size_t count = len;
 262         ssize_t ret;
 263
 264         if (!capable(CAP_NET_ADMIN))
 265                 return -EPERM;
 266
 267         /* ignore trailing newline */
 268         if (len >  0 && buf[len - 1] == '\n')
 269                 --count;
 270
 271         if (!rtnl_trylock())
 272                 return restart_syscall();
 273         ret = dev_set_alias(netdev, buf, count);
 274         rtnl_unlock();
 275
 276         return ret < 0 ? ret : len;
 277 }
 278
 279 static ssize_t show_ifalias(struct device *dev,
 280                             struct device_attribute *attr, char *buf)
 281 {
 282         const struct net_device *netdev = to_net_dev(dev);
 283         ssize_t ret = 0;
 284
 285         if (!rtnl_trylock())
 286                 return restart_syscall();
 287         if (netdev->ifalias)
 288                 ret = sprintf(buf, "%s\n", netdev->ifalias);
 289         rtnl_unlock();
 290         return ret;
 291 }
 292
 293 NETDEVICE_SHOW(group, fmt_dec);
 294
 295 static int change_group(struct net_device *net, unsigned long new_group)
 296 {
 297         dev_set_group(net, (int) new_group);
 298         return 0;
 299 }
 300
 301 static ssize_t store_group(struct device *dev, struct device_attribute *attr,
 302                          const char *buf, size_t len)
 303 {
 304         return netdev_store(dev, attr, buf, len, change_group);
 305 }
 306
 307 static struct device_attribute net_class_attributes[] = {
 308         __ATTR(addr_assign_type, S_IRUGO, show_addr_assign_type, NULL),
 309         __ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
 310         __ATTR(dev_id, S_IRUGO, show_dev_id, NULL),
 311         __ATTR(ifalias, S_IRUGO | S_IWUSR, show_ifalias, store_ifalias),
 312         __ATTR(iflink, S_IRUGO, show_iflink, NULL),
 313         __ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
 314         __ATTR(type, S_IRUGO, show_type, NULL),
 315         __ATTR(link_mode, S_IRUGO, show_link_mode, NULL),
 316         __ATTR(address, S_IRUGO, show_address, NULL),
 317         __ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
 318         __ATTR(carrier, S_IRUGO, show_carrier, NULL),
 319         __ATTR(speed, S_IRUGO, show_speed, NULL),
 320         __ATTR(duplex, S_IRUGO, show_duplex, NULL),
 321         __ATTR(dormant, S_IRUGO, show_dormant, NULL),
 322         __ATTR(operstate, S_IRUGO, show_operstate, NULL),
 323         __ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
 324         __ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
 325         __ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
 326                store_tx_queue_len),
 327         __ATTR(netdev_group, S_IRUGO | S_IWUSR, show_group, store_group),
 328         {}
 329 };
 330
 331 /* Show a given an attribute in the statistics group */
 332 static ssize_t netstat_show(const struct device *d,
 333                             struct device_attribute *attr, char *buf,
 334                             unsigned long offset)
 335 {
 336         struct net_device *dev = to_net_dev(d);
 337         ssize_t ret = -EINVAL;
 338
 339         WARN_ON(offset > sizeof(struct rtnl_link_stats64) ||
 340                         offset % sizeof(u64) != 0);
 341
 342         read_lock(&dev_base_lock);
 343         if (dev_isalive(dev)) {
 344                 struct rtnl_link_stats64 temp;
 345                 const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp);
 346
 347                 ret = sprintf(buf, fmt_u64, *(u64 *)(((u8 *) stats) + offset));
 348         }
 349         read_unlock(&dev_base_lock);
 350         return ret;
 351 }
 352
 353 /* generate a read-only statistics attribute */
 354 #define NETSTAT_ENTRY(name)                                             \
 355 static ssize_t show_##name(struct device *d,                            \
 356                            struct device_attribute *attr, char *buf)    \
 357 {                                                                       \
 358         return netstat_show(d, attr, buf,                               \
 359                             offsetof(struct rtnl_link_stats64, name));  \
 360 }                                                                       \
 361 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
 362
 363 NETSTAT_ENTRY(rx_packets);
 364 NETSTAT_ENTRY(tx_packets);
 365 NETSTAT_ENTRY(rx_bytes);
 366 NETSTAT_ENTRY(tx_bytes);
 367 NETSTAT_ENTRY(rx_errors);
 368 NETSTAT_ENTRY(tx_errors);
 369 NETSTAT_ENTRY(rx_dropped);
 370 NETSTAT_ENTRY(tx_dropped);
 371 NETSTAT_ENTRY(multicast);
 372 NETSTAT_ENTRY(collisions);
 373 NETSTAT_ENTRY(rx_length_errors);
 374 NETSTAT_ENTRY(rx_over_errors);
 375 NETSTAT_ENTRY(rx_crc_errors);
 376 NETSTAT_ENTRY(rx_frame_errors);
 377 NETSTAT_ENTRY(rx_fifo_errors);
 378 NETSTAT_ENTRY(rx_missed_errors);
 379 NETSTAT_ENTRY(tx_aborted_errors);
 380 NETSTAT_ENTRY(tx_carrier_errors);
 381 NETSTAT_ENTRY(tx_fifo_errors);
 382 NETSTAT_ENTRY(tx_heartbeat_errors);
 383 NETSTAT_ENTRY(tx_window_errors);
 384 NETSTAT_ENTRY(rx_compressed);
 385 NETSTAT_ENTRY(tx_compressed);
 386
 387 static struct attribute *netstat_attrs[] = {
 388         &dev_attr_rx_packets.attr,
 389         &dev_attr_tx_packets.attr,
 390         &dev_attr_rx_bytes.attr,
 391         &dev_attr_tx_bytes.attr,
 392         &dev_attr_rx_errors.attr,
 393         &dev_attr_tx_errors.attr,
 394         &dev_attr_rx_dropped.attr,
 395         &dev_attr_tx_dropped.attr,
 396         &dev_attr_multicast.attr,
 397         &dev_attr_collisions.attr,
 398         &dev_attr_rx_length_errors.attr,
 399         &dev_attr_rx_over_errors.attr,
 400         &dev_attr_rx_crc_errors.attr,
 401         &dev_attr_rx_frame_errors.attr,
 402         &dev_attr_rx_fifo_errors.attr,
 403         &dev_attr_rx_missed_errors.attr,
 404         &dev_attr_tx_aborted_errors.attr,
 405         &dev_attr_tx_carrier_errors.attr,
 406         &dev_attr_tx_fifo_errors.attr,
 407         &dev_attr_tx_heartbeat_errors.attr,
 408         &dev_attr_tx_window_errors.attr,
 409         &dev_attr_rx_compressed.attr,
 410         &dev_attr_tx_compressed.attr,
 411         NULL
 412 };
 413
 414
 415 static struct attribute_group netstat_group = {
 416         .name  = "statistics",
 417         .attrs  = netstat_attrs,
 418 };
 419
 420 #ifdef CONFIG_WIRELESS_EXT_SYSFS
 421 /* helper function that does all the locking etc for wireless stats */
 422 static ssize_t wireless_show(struct device *d, char *buf,
 423                              ssize_t (*format)(const struct iw_statistics *,
 424                                                char *))
 425 {
 426         struct net_device *dev = to_net_dev(d);
 427         const struct iw_statistics *iw;
 428         ssize_t ret = -EINVAL;
 429
 430         if (!rtnl_trylock())
 431                 return restart_syscall();
 432         if (dev_isalive(dev)) {
 433                 iw = get_wireless_stats(dev);
 434                 if (iw)
 435                         ret = (*format)(iw, buf);
 436         }
 437         rtnl_unlock();
 438
 439         return ret;
 440 }
 441
 442 /* show function template for wireless fields */
 443 #define WIRELESS_SHOW(name, field, format_string)                       \
 444 static ssize_t format_iw_##name(const struct iw_statistics *iw, char *buf) \
 445 {                                                                       \
 446         return sprintf(buf, format_string, iw->field);                  \
 447 }                                                                       \
 448 static ssize_t show_iw_##name(struct device *d,                         \
 449                               struct device_attribute *attr, char *buf) \
 450 {                                                                       \
 451         return wireless_show(d, buf, format_iw_##name);                 \
 452 }                                                                       \
 453 static DEVICE_ATTR(name, S_IRUGO, show_iw_##name, NULL)
 454
 455 WIRELESS_SHOW(status, status, fmt_hex);
 456 WIRELESS_SHOW(link, qual.qual, fmt_dec);
 457 WIRELESS_SHOW(level, qual.level, fmt_dec);
 458 WIRELESS_SHOW(noise, qual.noise, fmt_dec);
 459 WIRELESS_SHOW(nwid, discard.nwid, fmt_dec);
 460 WIRELESS_SHOW(crypt, discard.code, fmt_dec);
 461 WIRELESS_SHOW(fragment, discard.fragment, fmt_dec);
 462 WIRELESS_SHOW(misc, discard.misc, fmt_dec);
 463 WIRELESS_SHOW(retries, discard.retries, fmt_dec);
 464 WIRELESS_SHOW(beacon, miss.beacon, fmt_dec);
 465
 466 static struct attribute *wireless_attrs[] = {
 467         &dev_attr_status.attr,
 468         &dev_attr_link.attr,
 469         &dev_attr_level.attr,
 470         &dev_attr_noise.attr,
 471         &dev_attr_nwid.attr,
 472         &dev_attr_crypt.attr,
 473         &dev_attr_fragment.attr,
 474         &dev_attr_retries.attr,
 475         &dev_attr_misc.attr,
 476         &dev_attr_beacon.attr,
 477         NULL
 478 };
 479
 480 static struct attribute_group wireless_group = {
 481         .name = "wireless",
 482         .attrs = wireless_attrs,
 483 };
 484 #endif
 485 #endif /* CONFIG_SYSFS */
 486
 487 #ifdef CONFIG_RPS
 488 /*
 489  * RX queue sysfs structures and functions.
 490  */
 491 struct rx_queue_attribute {
 492         struct attribute attr;
 493         ssize_t (*show)(struct netdev_rx_queue *queue,
 494             struct rx_queue_attribute *attr, char *buf);
 495         ssize_t (*store)(struct netdev_rx_queue *queue,
 496             struct rx_queue_attribute *attr, const char *buf, size_t len);
 497 };
 498 #define to_rx_queue_attr(_attr) container_of(_attr,             \
 499     struct rx_queue_attribute, attr)
 500
 501 #define to_rx_queue(obj) container_of(obj, struct netdev_rx_queue, kobj)
 502
 503 static ssize_t rx_queue_attr_show(struct kobject *kobj, struct attribute *attr,
 504                                   char *buf)
 505 {
 506         struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
 507         struct netdev_rx_queue *queue = to_rx_queue(kobj);
 508
 509         if (!attribute->show)
 510                 return -EIO;
 511
 512         return attribute->show(queue, attribute, buf);
 513 }
 514
 515 static ssize_t rx_queue_attr_store(struct kobject *kobj, struct attribute *attr,
 516                                    const char *buf, size_t count)
 517 {
 518         struct rx_queue_attribute *attribute = to_rx_queue_attr(attr);
 519         struct netdev_rx_queue *queue = to_rx_queue(kobj);
 520
 521         if (!attribute->store)
 522                 return -EIO;
 523
 524         return attribute->store(queue, attribute, buf, count);
 525 }
 526
 527 static const struct sysfs_ops rx_queue_sysfs_ops = {
 528         .show = rx_queue_attr_show,
 529         .store = rx_queue_attr_store,
 530 };
 531
 532 static ssize_t show_rps_map(struct netdev_rx_queue *queue,
 533                             struct rx_queue_attribute *attribute, char *buf)
 534 {
 535         struct rps_map *map;
 536         cpumask_var_t mask;
 537         size_t len = 0;
 538         int i;
 539
 540         if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
 541                 return -ENOMEM;
 542
 543         rcu_read_lock();
 544         map = rcu_dereference(queue->rps_map);
 545         if (map)
 546                 for (i = 0; i < map->len; i++)
 547                         cpumask_set_cpu(map->cpus[i], mask);
 548
 549         len += cpumask_scnprintf(buf + len, PAGE_SIZE, mask);
 550         if (PAGE_SIZE - len < 3) {
 551                 rcu_read_unlock();
 552                 free_cpumask_var(mask);
 553                 return -EINVAL;
 554         }
 555         rcu_read_unlock();
 556
 557         free_cpumask_var(mask);
 558         len += sprintf(buf + len, "\n");
 559         return len;
 560 }
 561
 562 static ssize_t store_rps_map(struct netdev_rx_queue *queue,
 563                       struct rx_queue_attribute *attribute,
 564                       const char *buf, size_t len)
 565 {
 566         struct rps_map *old_map, *map;
 567         cpumask_var_t mask;
 568         int err, cpu, i;
 569         static DEFINE_SPINLOCK(rps_map_lock);
 570
 571         if (!capable(CAP_NET_ADMIN))
 572                 return -EPERM;
 573
 574         if (!alloc_cpumask_var(&mask, GFP_KERNEL))
 575                 return -ENOMEM;
 576
 577         err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
 578         if (err) {
 579                 free_cpumask_var(mask);
 580                 return err;
 581         }
 582
 583         map = kzalloc(max_t(unsigned,
 584             RPS_MAP_SIZE(cpumask_weight(mask)), L1_CACHE_BYTES),
 585             GFP_KERNEL);
 586         if (!map) {
 587                 free_cpumask_var(mask);
 588                 return -ENOMEM;
 589         }
 590
 591         i = 0;
 592         for_each_cpu_and(cpu, mask, cpu_online_mask)
 593                 map->cpus[i++] = cpu;
 594
 595         if (i)
 596                 map->len = i;
 597         else {
 598                 kfree(map);
 599                 map = NULL;
 600         }
 601
 602         spin_lock(&rps_map_lock);
 603         old_map = rcu_dereference_protected(queue->rps_map,
 604                                             lockdep_is_held(&rps_map_lock));
 605         rcu_assign_pointer(queue->rps_map, map);
 606         spin_unlock(&rps_map_lock);
 607
 608         if (old_map)
 609                 kfree_rcu(old_map, rcu);
 610
 611         free_cpumask_var(mask);
 612         return len;
 613 }
 614
 615 static ssize_t show_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
 616                                            struct rx_queue_attribute *attr,
 617                                            char *buf)
 618 {
 619         struct rps_dev_flow_table *flow_table;
 620         unsigned int val = 0;
 621
 622         rcu_read_lock();
 623         flow_table = rcu_dereference(queue->rps_flow_table);
 624         if (flow_table)
 625                 val = flow_table->mask + 1;
 626         rcu_read_unlock();
 627
 628         return sprintf(buf, "%u\n", val);
 629 }
 630
 631 static void rps_dev_flow_table_release_work(struct work_struct *work)
 632 {
 633         struct rps_dev_flow_table *table = container_of(work,
 634             struct rps_dev_flow_table, free_work);
 635
 636         vfree(table);
 637 }
 638
 639 static void rps_dev_flow_table_release(struct rcu_head *rcu)
 640 {
 641         struct rps_dev_flow_table *table = container_of(rcu,
 642             struct rps_dev_flow_table, rcu);
 643
 644         INIT_WORK(&table->free_work, rps_dev_flow_table_release_work);
 645         schedule_work(&table->free_work);
 646 }
 647
 648 static ssize_t store_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
 649                                      struct rx_queue_attribute *attr,
 650                                      const char *buf, size_t len)
 651 {
 652         unsigned int count;
 653         char *endp;
 654         struct rps_dev_flow_table *table, *old_table;
 655         static DEFINE_SPINLOCK(rps_dev_flow_lock);
 656
 657         if (!capable(CAP_NET_ADMIN))
 658                 return -EPERM;
 659
 660         count = simple_strtoul(buf, &endp, 0);
 661         if (endp == buf)
 662                 return -EINVAL;
 663
 664         if (count) {
 665                 int i;
 666
 667                 if (count > 1<<30) {
 668                         /* Enforce a limit to prevent overflow */
 669                         return -EINVAL;
 670                 }
 671                 count = roundup_pow_of_two(count);
 672                 table = vmalloc(RPS_DEV_FLOW_TABLE_SIZE(count));
 673                 if (!table)
 674                         return -ENOMEM;
 675
 676                 table->mask = count - 1;
 677                 for (i = 0; i < count; i++)
 678                         table->flows[i].cpu = RPS_NO_CPU;
 679         } else
 680                 table = NULL;
 681
 682         spin_lock(&rps_dev_flow_lock);
 683         old_table = rcu_dereference_protected(queue->rps_flow_table,
 684                                               lockdep_is_held(&rps_dev_flow_lock));
 685         rcu_assign_pointer(queue->rps_flow_table, table);
 686         spin_unlock(&rps_dev_flow_lock);
 687
 688         if (old_table)
 689                 call_rcu(&old_table->rcu, rps_dev_flow_table_release);
 690
 691         return len;
 692 }
 693
 694 static struct rx_queue_attribute rps_cpus_attribute =
 695         __ATTR(rps_cpus, S_IRUGO | S_IWUSR, show_rps_map, store_rps_map);
 696
 697
 698 static struct rx_queue_attribute rps_dev_flow_table_cnt_attribute =
 699         __ATTR(rps_flow_cnt, S_IRUGO | S_IWUSR,
 700             show_rps_dev_flow_table_cnt, store_rps_dev_flow_table_cnt);
 701
 702 static struct attribute *rx_queue_default_attrs[] = {
 703         &rps_cpus_attribute.attr,
 704         &rps_dev_flow_table_cnt_attribute.attr,
 705         NULL
 706 };
 707
 708 static void rx_queue_release(struct kobject *kobj)
 709 {
 710         struct netdev_rx_queue *queue = to_rx_queue(kobj);
 711         struct rps_map *map;
 712         struct rps_dev_flow_table *flow_table;
 713
 714
 715         map = rcu_dereference_protected(queue->rps_map, 1);
 716         if (map) {
 717                 RCU_INIT_POINTER(queue->rps_map, NULL);
 718                 kfree_rcu(map, rcu);
 719         }
 720
 721         flow_table = rcu_dereference_protected(queue->rps_flow_table, 1);
 722         if (flow_table) {
 723                 RCU_INIT_POINTER(queue->rps_flow_table, NULL);
 724                 call_rcu(&flow_table->rcu, rps_dev_flow_table_release);
 725         }
 726
 727         memset(kobj, 0, sizeof(*kobj));
 728         dev_put(queue->dev);
 729 }
 730
 731 static struct kobj_type rx_queue_ktype = {
 732         .sysfs_ops = &rx_queue_sysfs_ops,
 733         .release = rx_queue_release,
 734         .default_attrs = rx_queue_default_attrs,
 735 };
 736
 737 static int rx_queue_add_kobject(struct net_device *net, int index)
 738 {
 739         struct netdev_rx_queue *queue = net->_rx + index;
 740         struct kobject *kobj = &queue->kobj;
 741         int error = 0;
 742
 743         kobj->kset = net->queues_kset;
 744         error = kobject_init_and_add(kobj, &rx_queue_ktype, NULL,
 745             "rx-%u", index);
 746         if (error) {
 747                 kobject_put(kobj);
 748                 return error;
 749         }
 750
 751         kobject_uevent(kobj, KOBJ_ADD);
 752         dev_hold(queue->dev);
 753
 754         return error;
 755 }
 756 #endif /* CONFIG_RPS */
 757
 758 int
 759 net_rx_queue_update_kobjects(struct net_device *net, int old_num, int new_num)
 760 {
 761 #ifdef CONFIG_RPS
 762         int i;
 763         int error = 0;
 764
 765         for (i = old_num; i < new_num; i++) {
 766                 error = rx_queue_add_kobject(net, i);
 767                 if (error) {
 768                         new_num = old_num;
 769                         break;
 770                 }
 771         }
 772
 773         while (--i >= new_num)
 774                 kobject_put(&net->_rx[i].kobj);
 775
 776         return error;
 777 #else
 778         return 0;
 779 #endif
 780 }
 781
 782 #ifdef CONFIG_XPS
 783 /*
 784  * netdev_queue sysfs structures and functions.
 785  */
 786 struct netdev_queue_attribute {
 787         struct attribute attr;
 788         ssize_t (*show)(struct netdev_queue *queue,
 789             struct netdev_queue_attribute *attr, char *buf);
 790         ssize_t (*store)(struct netdev_queue *queue,
 791             struct netdev_queue_attribute *attr, const char *buf, size_t len);
 792 };
 793 #define to_netdev_queue_attr(_attr) container_of(_attr,         \
 794     struct netdev_queue_attribute, attr)
 795
 796 #define to_netdev_queue(obj) container_of(obj, struct netdev_queue, kobj)
 797
 798 static ssize_t netdev_queue_attr_show(struct kobject *kobj,
 799                                       struct attribute *attr, char *buf)
 800 {
 801         struct netdev_queue_attribute *attribute = to_netdev_queue_attr(attr);
 802         struct netdev_queue *queue = to_netdev_queue(kobj);
 803
 804         if (!attribute->show)
 805                 return -EIO;
 806
 807         return attribute->show(queue, attribute, buf);
 808 }
 809
 810 static ssize_t netdev_queue_attr_store(struct kobject *kobj,
 811                                        struct attribute *attr,
 812                                        const char *buf, size_t count)
 813 {
 814         struct netdev_queue_attribute *attribute = to_netdev_queue_attr(attr);
 815         struct netdev_queue *queue = to_netdev_queue(kobj);
 816
 817         if (!attribute->store)
 818                 return -EIO;
 819
 820         return attribute->store(queue, attribute, buf, count);
 821 }
 822
 823 static const struct sysfs_ops netdev_queue_sysfs_ops = {
 824         .show = netdev_queue_attr_show,
 825         .store = netdev_queue_attr_store,
 826 };
 827
 828 static inline unsigned int get_netdev_queue_index(struct netdev_queue *queue)
 829 {
 830         struct net_device *dev = queue->dev;
 831         int i;
 832
 833         for (i = 0; i < dev->num_tx_queues; i++)
 834                 if (queue == &dev->_tx[i])
 835                         break;
 836
 837         BUG_ON(i >= dev->num_tx_queues);
 838
 839         return i;
 840 }
 841
 842
 843 static ssize_t show_xps_map(struct netdev_queue *queue,
 844                             struct netdev_queue_attribute *attribute, char *buf)
 845 {
 846         struct net_device *dev = queue->dev;
 847         struct xps_dev_maps *dev_maps;
 848         cpumask_var_t mask;
 849         unsigned long index;
 850         size_t len = 0;
 851         int i;
 852
 853         if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
 854                 return -ENOMEM;
 855
 856         index = get_netdev_queue_index(queue);
 857
 858         rcu_read_lock();
 859         dev_maps = rcu_dereference(dev->xps_maps);
 860         if (dev_maps) {
 861                 for_each_possible_cpu(i) {
 862                         struct xps_map *map =
 863                             rcu_dereference(dev_maps->cpu_map[i]);
 864                         if (map) {
 865                                 int j;
 866                                 for (j = 0; j < map->len; j++) {
 867                                         if (map->queues[j] == index) {
 868                                                 cpumask_set_cpu(i, mask);
 869                                                 break;
 870                                         }
 871                                 }
 872                         }
 873                 }
 874         }
 875         rcu_read_unlock();
 876
 877         len += cpumask_scnprintf(buf + len, PAGE_SIZE, mask);
 878         if (PAGE_SIZE - len < 3) {
 879                 free_cpumask_var(mask);
 880                 return -EINVAL;
 881         }
 882
 883         free_cpumask_var(mask);
 884         len += sprintf(buf + len, "\n");
 885         return len;
 886 }
 887
 888 static DEFINE_MUTEX(xps_map_mutex);
 889 #define xmap_dereference(P)             \
 890         rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
 891
 892 static ssize_t store_xps_map(struct netdev_queue *queue,
 893                       struct netdev_queue_attribute *attribute,
 894                       const char *buf, size_t len)
 895 {
 896         struct net_device *dev = queue->dev;
 897         cpumask_var_t mask;
 898         int err, i, cpu, pos, map_len, alloc_len, need_set;
 899         unsigned long index;
 900         struct xps_map *map, *new_map;
 901         struct xps_dev_maps *dev_maps, *new_dev_maps;
 902         int nonempty = 0;
 903         int numa_node = -2;
 904
 905         if (!capable(CAP_NET_ADMIN))
 906                 return -EPERM;
 907
 908         if (!alloc_cpumask_var(&mask, GFP_KERNEL))
 909                 return -ENOMEM;
 910
 911         index = get_netdev_queue_index(queue);
 912
 913         err = bitmap_parse(buf, len, cpumask_bits(mask), nr_cpumask_bits);
 914         if (err) {
 915                 free_cpumask_var(mask);
 916                 return err;
 917         }
 918
 919         new_dev_maps = kzalloc(max_t(unsigned,
 920             XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES), GFP_KERNEL);
 921         if (!new_dev_maps) {
 922                 free_cpumask_var(mask);
 923                 return -ENOMEM;
 924         }
 925
 926         mutex_lock(&xps_map_mutex);
 927
 928         dev_maps = xmap_dereference(dev->xps_maps);
 929
 930         for_each_possible_cpu(cpu) {
 931                 map = dev_maps ?
 932                         xmap_dereference(dev_maps->cpu_map[cpu]) : NULL;
 933                 new_map = map;
 934                 if (map) {
 935                         for (pos = 0; pos < map->len; pos++)
 936                                 if (map->queues[pos] == index)
 937                                         break;
 938                         map_len = map->len;
 939                         alloc_len = map->alloc_len;
 940                 } else
 941                         pos = map_len = alloc_len = 0;
 942
 943                 need_set = cpumask_test_cpu(cpu, mask) && cpu_online(cpu);
 944 #ifdef CONFIG_NUMA
 945                 if (need_set) {
 946                         if (numa_node == -2)
 947                                 numa_node = cpu_to_node(cpu);
 948                         else if (numa_node != cpu_to_node(cpu))
 949                                 numa_node = -1;
 950                 }
 951 #endif
 952                 if (need_set && pos >= map_len) {
 953                         /* Need to add queue to this CPU's map */
 954                         if (map_len >= alloc_len) {
 955                                 alloc_len = alloc_len ?
 956                                     2 * alloc_len : XPS_MIN_MAP_ALLOC;
 957                                 new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len),
 958                                                        GFP_KERNEL,
 959                                                        cpu_to_node(cpu));
 960                                 if (!new_map)
 961                                         goto error;
 962                                 new_map->alloc_len = alloc_len;
 963                                 for (i = 0; i < map_len; i++)
 964                                         new_map->queues[i] = map->queues[i];
 965                                 new_map->len = map_len;
 966                         }
 967                         new_map->queues[new_map->len++] = index;
 968                 } else if (!need_set && pos < map_len) {
 969                         /* Need to remove queue from this CPU's map */
 970                         if (map_len > 1)
 971                                 new_map->queues[pos] =
 972                                     new_map->queues[--new_map->len];
 973                         else
 974                                 new_map = NULL;
 975                 }
 976                 RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], new_map);
 977         }
 978
 979         /* Cleanup old maps */
 980         for_each_possible_cpu(cpu) {
 981                 map = dev_maps ?
 982                         xmap_dereference(dev_maps->cpu_map[cpu]) : NULL;
 983                 if (map && xmap_dereference(new_dev_maps->cpu_map[cpu]) != map)
 984                         kfree_rcu(map, rcu);
 985                 if (new_dev_maps->cpu_map[cpu])
 986                         nonempty = 1;
 987         }
 988
 989         if (nonempty)
 990                 RCU_INIT_POINTER(dev->xps_maps, new_dev_maps);
 991         else {
 992                 kfree(new_dev_maps);
 993                 RCU_INIT_POINTER(dev->xps_maps, NULL);
 994         }
 995
 996         if (dev_maps)
 997                 kfree_rcu(dev_maps, rcu);
 998
 999         netdev_queue_numa_node_write(queue, (numa_node >= 0) ? numa_node :
1000                                             NUMA_NO_NODE);
1001
1002         mutex_unlock(&xps_map_mutex);
1003
1004         free_cpumask_var(mask);
1005         return len;
1006
1007 error:
1008         mutex_unlock(&xps_map_mutex);
1009
1010         if (new_dev_maps)
1011                 for_each_possible_cpu(i)
1012                         kfree(rcu_dereference_protected(
1013                                 new_dev_maps->cpu_map[i],
1014                                 1));
1015         kfree(new_dev_maps);
1016         free_cpumask_var(mask);
1017         return -ENOMEM;
1018 }
1019
1020 static struct netdev_queue_attribute xps_cpus_attribute =
1021     __ATTR(xps_cpus, S_IRUGO | S_IWUSR, show_xps_map, store_xps_map);
1022
1023 static struct attribute *netdev_queue_default_attrs[] = {
1024         &xps_cpus_attribute.attr,
1025         NULL
1026 };
1027
1028 static void netdev_queue_release(struct kobject *kobj)
1029 {
1030         struct netdev_queue *queue = to_netdev_queue(kobj);
1031         struct net_device *dev = queue->dev;
1032         struct xps_dev_maps *dev_maps;
1033         struct xps_map *map;
1034         unsigned long index;
1035         int i, pos, nonempty = 0;
1036
1037         index = get_netdev_queue_index(queue);
1038
1039         mutex_lock(&xps_map_mutex);
1040         dev_maps = xmap_dereference(dev->xps_maps);
1041
1042         if (dev_maps) {
1043                 for_each_possible_cpu(i) {
1044                         map = xmap_dereference(dev_maps->cpu_map[i]);
1045                         if (!map)
1046                                 continue;
1047
1048                         for (pos = 0; pos < map->len; pos++)
1049                                 if (map->queues[pos] == index)
1050                                         break;
1051
1052                         if (pos < map->len) {
1053                                 if (map->len > 1)
1054                                         map->queues[pos] =
1055                                             map->queues[--map->len];
1056                                 else {
1057                                         RCU_INIT_POINTER(dev_maps->cpu_map[i],
1058                                             NULL);
1059                                         kfree_rcu(map, rcu);
1060                                         map = NULL;
1061                                 }
1062                         }
1063                         if (map)
1064                                 nonempty = 1;
1065                 }
1066
1067                 if (!nonempty) {
1068                         RCU_INIT_POINTER(dev->xps_maps, NULL);
1069                         kfree_rcu(dev_maps, rcu);
1070                 }
1071         }
1072
1073         mutex_unlock(&xps_map_mutex);
1074
1075         memset(kobj, 0, sizeof(*kobj));
1076         dev_put(queue->dev);
1077 }
1078
1079 static struct kobj_type netdev_queue_ktype = {
1080         .sysfs_ops = &netdev_queue_sysfs_ops,
1081         .release = netdev_queue_release,
1082         .default_attrs = netdev_queue_default_attrs,
1083 };
1084
1085 static int netdev_queue_add_kobject(struct net_device *net, int index)
1086 {
1087         struct netdev_queue *queue = net->_tx + index;
1088         struct kobject *kobj = &queue->kobj;
1089         int error = 0;
1090
1091         kobj->kset = net->queues_kset;
1092         error = kobject_init_and_add(kobj, &netdev_queue_ktype, NULL,
1093             "tx-%u", index);
1094         if (error) {
1095                 kobject_put(kobj);
1096                 return error;
1097         }
1098
1099         kobject_uevent(kobj, KOBJ_ADD);
1100         dev_hold(queue->dev);
1101
1102         return error;
1103 }
1104 #endif /* CONFIG_XPS */
1105
1106 int
1107 netdev_queue_update_kobjects(struct net_device *net, int old_num, int new_num)
1108 {
1109 #ifdef CONFIG_XPS
1110         int i;
1111         int error = 0;
1112
1113         for (i = old_num; i < new_num; i++) {
1114                 error = netdev_queue_add_kobject(net, i);
1115                 if (error) {
1116                         new_num = old_num;
1117                         break;
1118                 }
1119         }
1120
1121         while (--i >= new_num)
1122                 kobject_put(&net->_tx[i].kobj);
1123
1124         return error;
1125 #else
1126         return 0;
1127 #endif
1128 }
1129
1130 static int register_queue_kobjects(struct net_device *net)
1131 {
1132         int error = 0, txq = 0, rxq = 0, real_rx = 0, real_tx = 0;
1133
1134 #if defined(CONFIG_RPS) || defined(CONFIG_XPS)
1135         net->queues_kset = kset_create_and_add("queues",
1136             NULL, &net->dev.kobj);
1137         if (!net->queues_kset)
1138                 return -ENOMEM;
1139 #endif
1140
1141 #ifdef CONFIG_RPS
1142         real_rx = net->real_num_rx_queues;
1143 #endif
1144         real_tx = net->real_num_tx_queues;
1145
1146         error = net_rx_queue_update_kobjects(net, 0, real_rx);
1147         if (error)
1148                 goto error;
1149         rxq = real_rx;
1150
1151         error = netdev_queue_update_kobjects(net, 0, real_tx);
1152         if (error)
1153                 goto error;
1154         txq = real_tx;
1155
1156         return 0;
1157
1158 error:
1159         netdev_queue_update_kobjects(net, txq, 0);
1160         net_rx_queue_update_kobjects(net, rxq, 0);
1161         return error;
1162 }
1163
1164 static void remove_queue_kobjects(struct net_device *net)
1165 {
1166         int real_rx = 0, real_tx = 0;
1167
1168 #ifdef CONFIG_RPS
1169         real_rx = net->real_num_rx_queues;
1170 #endif
1171         real_tx = net->real_num_tx_queues;
1172
1173         net_rx_queue_update_kobjects(net, real_rx, 0);
1174         netdev_queue_update_kobjects(net, real_tx, 0);
1175 #if defined(CONFIG_RPS) || defined(CONFIG_XPS)
1176         kset_unregister(net->queues_kset);
1177 #endif
1178 }
1179
1180 static void *net_grab_current_ns(void)
1181 {
1182         struct net *ns = current->nsproxy->net_ns;
1183 #ifdef CONFIG_NET_NS
1184         if (ns)
1185                 atomic_inc(&ns->passive);
1186 #endif
1187         return ns;
1188 }
1189
1190 static const void *net_initial_ns(void)
1191 {
1192         return &init_net;
1193 }
1194
1195 static const void *net_netlink_ns(struct sock *sk)
1196 {
1197         return sock_net(sk);
1198 }
1199
1200 struct kobj_ns_type_operations net_ns_type_operations = {
1201         .type = KOBJ_NS_TYPE_NET,
1202         .grab_current_ns = net_grab_current_ns,
1203         .netlink_ns = net_netlink_ns,
1204         .initial_ns = net_initial_ns,
1205         .drop_ns = net_drop_ns,
1206 };
1207 EXPORT_SYMBOL_GPL(net_ns_type_operations);
1208
1209 #ifdef CONFIG_HOTPLUG
1210 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
1211 {
1212         struct net_device *dev = to_net_dev(d);
1213         int retval;
1214
1215         /* pass interface to uevent. */
1216         retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
1217         if (retval)
1218                 goto exit;
1219
1220         /* pass ifindex to uevent.
1221          * ifindex is useful as it won't change (interface name may change)
1222          * and is what RtNetlink uses natively. */
1223         retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
1224
1225 exit:
1226         return retval;
1227 }
1228 #endif
1229
1230 /*
1231  *      netdev_release -- destroy and free a dead device.
1232  *      Called when last reference to device kobject is gone.
1233  */
1234 static void netdev_release(struct device *d)
1235 {
1236         struct net_device *dev = to_net_dev(d);
1237
1238         BUG_ON(dev->reg_state != NETREG_RELEASED);
1239
1240         kfree(dev->ifalias);
1241         kfree((char *)dev - dev->padded);
1242 }
1243
1244 static const void *net_namespace(struct device *d)
1245 {
1246         struct net_device *dev;
1247         dev = container_of(d, struct net_device, dev);
1248         return dev_net(dev);
1249 }
1250
1251 static struct class net_class = {
1252         .name = "net",
1253         .dev_release = netdev_release,
1254 #ifdef CONFIG_SYSFS
1255         .dev_attrs = net_class_attributes,
1256 #endif /* CONFIG_SYSFS */
1257 #ifdef CONFIG_HOTPLUG
1258         .dev_uevent = netdev_uevent,
1259 #endif
1260         .ns_type = &net_ns_type_operations,
1261         .namespace = net_namespace,
1262 };
1263
1264 /* Delete sysfs entries but hold kobject reference until after all
1265  * netdev references are gone.
1266  */
1267 void netdev_unregister_kobject(struct net_device * net)
1268 {
1269         struct device *dev = &(net->dev);
1270
1271         kobject_get(&dev->kobj);
1272
1273         remove_queue_kobjects(net);
1274
1275         device_del(dev);
1276 }
1277
1278 /* Create sysfs entries for network device. */
1279 int netdev_register_kobject(struct net_device *net)
1280 {
1281         struct device *dev = &(net->dev);
1282         const struct attribute_group **groups = net->sysfs_groups;
1283         int error = 0;
1284
1285         device_initialize(dev);
1286         dev->class = &net_class;
1287         dev->platform_data = net;
1288         dev->groups = groups;
1289
1290         dev_set_name(dev, "%s", net->name);
1291
1292 #ifdef CONFIG_SYSFS
1293         /* Allow for a device specific group */
1294         if (*groups)
1295                 groups++;
1296
1297         *groups++ = &netstat_group;
1298 #ifdef CONFIG_WIRELESS_EXT_SYSFS
1299         if (net->ieee80211_ptr)
1300                 *groups++ = &wireless_group;
1301 #ifdef CONFIG_WIRELESS_EXT
1302         else if (net->wireless_handlers)
1303                 *groups++ = &wireless_group;
1304 #endif
1305 #endif
1306 #endif /* CONFIG_SYSFS */
1307
1308         error = device_add(dev);
1309         if (error)
1310                 return error;
1311
1312         error = register_queue_kobjects(net);
1313         if (error) {
1314                 device_del(dev);
1315                 return error;
1316         }
1317
1318         return error;
1319 }
1320
1321 int netdev_class_create_file(struct class_attribute *class_attr)
1322 {
1323         return class_create_file(&net_class, class_attr);
1324 }
1325 EXPORT_SYMBOL(netdev_class_create_file);
1326
1327 void netdev_class_remove_file(struct class_attribute *class_attr)
1328 {
1329         class_remove_file(&net_class, class_attr);
1330 }
1331 EXPORT_SYMBOL(netdev_class_remove_file);
1332
1333 int netdev_kobject_init(void)
1334 {
1335         kobj_ns_type_register(&net_ns_type_operations);
1336         return class_register(&net_class);
1337 }