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 <net/sock.h>
  17 #include <linux/rtnetlink.h>
  18 #include <linux/wireless.h>
  19 #include <net/wext.h>
  20
  21 #include "net-sysfs.h"
  22
  23 #ifdef CONFIG_SYSFS
  24 static const char fmt_hex[] = "%#x\n";
  25 static const char fmt_long_hex[] = "%#lx\n";
  26 static const char fmt_dec[] = "%d\n";
  27 static const char fmt_ulong[] = "%lu\n";
  28
  29 static inline int dev_isalive(const struct net_device *dev)
  30 {
  31         return dev->reg_state <= NETREG_REGISTERED;
  32 }
  33
  34 /* use same locking rules as GIF* ioctl's */
  35 static ssize_t netdev_show(const struct device *dev,
  36                            struct device_attribute *attr, char *buf,
  37                            ssize_t (*format)(const struct net_device *, char *))
  38 {
  39         struct net_device *net = to_net_dev(dev);
  40         ssize_t ret = -EINVAL;
  41
  42         read_lock(&dev_base_lock);
  43         if (dev_isalive(net))
  44                 ret = (*format)(net, buf);
  45         read_unlock(&dev_base_lock);
  46
  47         return ret;
  48 }
  49
  50 /* generate a show function for simple field */
  51 #define NETDEVICE_SHOW(field, format_string)                            \
  52 static ssize_t format_##field(const struct net_device *net, char *buf)  \
  53 {                                                                       \
  54         return sprintf(buf, format_string, net->field);                 \
  55 }                                                                       \
  56 static ssize_t show_##field(struct device *dev,                         \
  57                             struct device_attribute *attr, char *buf)   \
  58 {                                                                       \
  59         return netdev_show(dev, attr, buf, format_##field);             \
  60 }
  61
  62
  63 /* use same locking and permission rules as SIF* ioctl's */
  64 static ssize_t netdev_store(struct device *dev, struct device_attribute *attr,
  65                             const char *buf, size_t len,
  66                             int (*set)(struct net_device *, unsigned long))
  67 {
  68         struct net_device *net = to_net_dev(dev);
  69         char *endp;
  70         unsigned long new;
  71         int ret = -EINVAL;
  72
  73         if (!capable(CAP_NET_ADMIN))
  74                 return -EPERM;
  75
  76         new = simple_strtoul(buf, &endp, 0);
  77         if (endp == buf)
  78                 goto err;
  79
  80         if (!rtnl_trylock())
  81                 return restart_syscall();
  82
  83         if (dev_isalive(net)) {
  84                 if ((ret = (*set)(net, new)) == 0)
  85                         ret = len;
  86         }
  87         rtnl_unlock();
  88  err:
  89         return ret;
  90 }
  91
  92 NETDEVICE_SHOW(dev_id, fmt_hex);
  93 NETDEVICE_SHOW(addr_len, fmt_dec);
  94 NETDEVICE_SHOW(iflink, fmt_dec);
  95 NETDEVICE_SHOW(ifindex, fmt_dec);
  96 NETDEVICE_SHOW(features, fmt_long_hex);
  97 NETDEVICE_SHOW(type, fmt_dec);
  98 NETDEVICE_SHOW(link_mode, fmt_dec);
  99
 100 /* use same locking rules as GIFHWADDR ioctl's */
 101 static ssize_t show_address(struct device *dev, struct device_attribute *attr,
 102                             char *buf)
 103 {
 104         struct net_device *net = to_net_dev(dev);
 105         ssize_t ret = -EINVAL;
 106
 107         read_lock(&dev_base_lock);
 108         if (dev_isalive(net))
 109                 ret = sysfs_format_mac(buf, net->dev_addr, net->addr_len);
 110         read_unlock(&dev_base_lock);
 111         return ret;
 112 }
 113
 114 static ssize_t show_broadcast(struct device *dev,
 115                             struct device_attribute *attr, char *buf)
 116 {
 117         struct net_device *net = to_net_dev(dev);
 118         if (dev_isalive(net))
 119                 return sysfs_format_mac(buf, net->broadcast, net->addr_len);
 120         return -EINVAL;
 121 }
 122
 123 static ssize_t show_carrier(struct device *dev,
 124                             struct device_attribute *attr, char *buf)
 125 {
 126         struct net_device *netdev = to_net_dev(dev);
 127         if (netif_running(netdev)) {
 128                 return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
 129         }
 130         return -EINVAL;
 131 }
 132
 133 static ssize_t show_speed(struct device *dev,
 134                           struct device_attribute *attr, char *buf)
 135 {
 136         struct net_device *netdev = to_net_dev(dev);
 137         int ret = -EINVAL;
 138
 139         if (!rtnl_trylock())
 140                 return restart_syscall();
 141
 142         if (netif_running(netdev) &&
 143             netdev->ethtool_ops &&
 144             netdev->ethtool_ops->get_settings) {
 145                 struct ethtool_cmd cmd = { ETHTOOL_GSET };
 146
 147                 if (!netdev->ethtool_ops->get_settings(netdev, &cmd))
 148                         ret = sprintf(buf, fmt_dec, ethtool_cmd_speed(&cmd));
 149         }
 150         rtnl_unlock();
 151         return ret;
 152 }
 153
 154 static ssize_t show_duplex(struct device *dev,
 155                            struct device_attribute *attr, char *buf)
 156 {
 157         struct net_device *netdev = to_net_dev(dev);
 158         int ret = -EINVAL;
 159
 160         if (!rtnl_trylock())
 161                 return restart_syscall();
 162
 163         if (netif_running(netdev) &&
 164             netdev->ethtool_ops &&
 165             netdev->ethtool_ops->get_settings) {
 166                 struct ethtool_cmd cmd = { ETHTOOL_GSET };
 167
 168                 if (!netdev->ethtool_ops->get_settings(netdev, &cmd))
 169                         ret = sprintf(buf, "%s\n", cmd.duplex ? "full" : "half");
 170         }
 171         rtnl_unlock();
 172         return ret;
 173 }
 174
 175 static ssize_t show_dormant(struct device *dev,
 176                             struct device_attribute *attr, char *buf)
 177 {
 178         struct net_device *netdev = to_net_dev(dev);
 179
 180         if (netif_running(netdev))
 181                 return sprintf(buf, fmt_dec, !!netif_dormant(netdev));
 182
 183         return -EINVAL;
 184 }
 185
 186 static const char *const operstates[] = {
 187         "unknown",
 188         "notpresent", /* currently unused */
 189         "down",
 190         "lowerlayerdown",
 191         "testing", /* currently unused */
 192         "dormant",
 193         "up"
 194 };
 195
 196 static ssize_t show_operstate(struct device *dev,
 197                               struct device_attribute *attr, char *buf)
 198 {
 199         const struct net_device *netdev = to_net_dev(dev);
 200         unsigned char operstate;
 201
 202         read_lock(&dev_base_lock);
 203         operstate = netdev->operstate;
 204         if (!netif_running(netdev))
 205                 operstate = IF_OPER_DOWN;
 206         read_unlock(&dev_base_lock);
 207
 208         if (operstate >= ARRAY_SIZE(operstates))
 209                 return -EINVAL; /* should not happen */
 210
 211         return sprintf(buf, "%s\n", operstates[operstate]);
 212 }
 213
 214 /* read-write attributes */
 215 NETDEVICE_SHOW(mtu, fmt_dec);
 216
 217 static int change_mtu(struct net_device *net, unsigned long new_mtu)
 218 {
 219         return dev_set_mtu(net, (int) new_mtu);
 220 }
 221
 222 static ssize_t store_mtu(struct device *dev, struct device_attribute *attr,
 223                          const char *buf, size_t len)
 224 {
 225         return netdev_store(dev, attr, buf, len, change_mtu);
 226 }
 227
 228 NETDEVICE_SHOW(flags, fmt_hex);
 229
 230 static int change_flags(struct net_device *net, unsigned long new_flags)
 231 {
 232         return dev_change_flags(net, (unsigned) new_flags);
 233 }
 234
 235 static ssize_t store_flags(struct device *dev, struct device_attribute *attr,
 236                            const char *buf, size_t len)
 237 {
 238         return netdev_store(dev, attr, buf, len, change_flags);
 239 }
 240
 241 NETDEVICE_SHOW(tx_queue_len, fmt_ulong);
 242
 243 static int change_tx_queue_len(struct net_device *net, unsigned long new_len)
 244 {
 245         net->tx_queue_len = new_len;
 246         return 0;
 247 }
 248
 249 static ssize_t store_tx_queue_len(struct device *dev,
 250                                   struct device_attribute *attr,
 251                                   const char *buf, size_t len)
 252 {
 253         return netdev_store(dev, attr, buf, len, change_tx_queue_len);
 254 }
 255
 256 static ssize_t store_ifalias(struct device *dev, struct device_attribute *attr,
 257                              const char *buf, size_t len)
 258 {
 259         struct net_device *netdev = to_net_dev(dev);
 260         size_t count = len;
 261         ssize_t ret;
 262
 263         if (!capable(CAP_NET_ADMIN))
 264                 return -EPERM;
 265
 266         /* ignore trailing newline */
 267         if (len >  0 && buf[len - 1] == '\n')
 268                 --count;
 269
 270         if (!rtnl_trylock())
 271                 return restart_syscall();
 272         ret = dev_set_alias(netdev, buf, count);
 273         rtnl_unlock();
 274
 275         return ret < 0 ? ret : len;
 276 }
 277
 278 static ssize_t show_ifalias(struct device *dev,
 279                             struct device_attribute *attr, char *buf)
 280 {
 281         const struct net_device *netdev = to_net_dev(dev);
 282         ssize_t ret = 0;
 283
 284         if (!rtnl_trylock())
 285                 return restart_syscall();
 286         if (netdev->ifalias)
 287                 ret = sprintf(buf, "%s\n", netdev->ifalias);
 288         rtnl_unlock();
 289         return ret;
 290 }
 291
 292 static struct device_attribute net_class_attributes[] = {
 293         __ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
 294         __ATTR(dev_id, S_IRUGO, show_dev_id, NULL),
 295         __ATTR(ifalias, S_IRUGO | S_IWUSR, show_ifalias, store_ifalias),
 296         __ATTR(iflink, S_IRUGO, show_iflink, NULL),
 297         __ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
 298         __ATTR(features, S_IRUGO, show_features, NULL),
 299         __ATTR(type, S_IRUGO, show_type, NULL),
 300         __ATTR(link_mode, S_IRUGO, show_link_mode, NULL),
 301         __ATTR(address, S_IRUGO, show_address, NULL),
 302         __ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
 303         __ATTR(carrier, S_IRUGO, show_carrier, NULL),
 304         __ATTR(speed, S_IRUGO, show_speed, NULL),
 305         __ATTR(duplex, S_IRUGO, show_duplex, NULL),
 306         __ATTR(dormant, S_IRUGO, show_dormant, NULL),
 307         __ATTR(operstate, S_IRUGO, show_operstate, NULL),
 308         __ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
 309         __ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
 310         __ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
 311                store_tx_queue_len),
 312         {}
 313 };
 314
 315 /* Show a given an attribute in the statistics group */
 316 static ssize_t netstat_show(const struct device *d,
 317                             struct device_attribute *attr, char *buf,
 318                             unsigned long offset)
 319 {
 320         struct net_device *dev = to_net_dev(d);
 321         ssize_t ret = -EINVAL;
 322
 323         WARN_ON(offset > sizeof(struct net_device_stats) ||
 324                         offset % sizeof(unsigned long) != 0);
 325
 326         read_lock(&dev_base_lock);
 327         if (dev_isalive(dev)) {
 328                 const struct net_device_stats *stats = dev_get_stats(dev);
 329                 ret = sprintf(buf, fmt_ulong,
 330                               *(unsigned long *)(((u8 *) stats) + offset));
 331         }
 332         read_unlock(&dev_base_lock);
 333         return ret;
 334 }
 335
 336 /* generate a read-only statistics attribute */
 337 #define NETSTAT_ENTRY(name)                                             \
 338 static ssize_t show_##name(struct device *d,                            \
 339                            struct device_attribute *attr, char *buf)    \
 340 {                                                                       \
 341         return netstat_show(d, attr, buf,                               \
 342                             offsetof(struct net_device_stats, name));   \
 343 }                                                                       \
 344 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
 345
 346 NETSTAT_ENTRY(rx_packets);
 347 NETSTAT_ENTRY(tx_packets);
 348 NETSTAT_ENTRY(rx_bytes);
 349 NETSTAT_ENTRY(tx_bytes);
 350 NETSTAT_ENTRY(rx_errors);
 351 NETSTAT_ENTRY(tx_errors);
 352 NETSTAT_ENTRY(rx_dropped);
 353 NETSTAT_ENTRY(tx_dropped);
 354 NETSTAT_ENTRY(multicast);
 355 NETSTAT_ENTRY(collisions);
 356 NETSTAT_ENTRY(rx_length_errors);
 357 NETSTAT_ENTRY(rx_over_errors);
 358 NETSTAT_ENTRY(rx_crc_errors);
 359 NETSTAT_ENTRY(rx_frame_errors);
 360 NETSTAT_ENTRY(rx_fifo_errors);
 361 NETSTAT_ENTRY(rx_missed_errors);
 362 NETSTAT_ENTRY(tx_aborted_errors);
 363 NETSTAT_ENTRY(tx_carrier_errors);
 364 NETSTAT_ENTRY(tx_fifo_errors);
 365 NETSTAT_ENTRY(tx_heartbeat_errors);
 366 NETSTAT_ENTRY(tx_window_errors);
 367 NETSTAT_ENTRY(rx_compressed);
 368 NETSTAT_ENTRY(tx_compressed);
 369
 370 static struct attribute *netstat_attrs[] = {
 371         &dev_attr_rx_packets.attr,
 372         &dev_attr_tx_packets.attr,
 373         &dev_attr_rx_bytes.attr,
 374         &dev_attr_tx_bytes.attr,
 375         &dev_attr_rx_errors.attr,
 376         &dev_attr_tx_errors.attr,
 377         &dev_attr_rx_dropped.attr,
 378         &dev_attr_tx_dropped.attr,
 379         &dev_attr_multicast.attr,
 380         &dev_attr_collisions.attr,
 381         &dev_attr_rx_length_errors.attr,
 382         &dev_attr_rx_over_errors.attr,
 383         &dev_attr_rx_crc_errors.attr,
 384         &dev_attr_rx_frame_errors.attr,
 385         &dev_attr_rx_fifo_errors.attr,
 386         &dev_attr_rx_missed_errors.attr,
 387         &dev_attr_tx_aborted_errors.attr,
 388         &dev_attr_tx_carrier_errors.attr,
 389         &dev_attr_tx_fifo_errors.attr,
 390         &dev_attr_tx_heartbeat_errors.attr,
 391         &dev_attr_tx_window_errors.attr,
 392         &dev_attr_rx_compressed.attr,
 393         &dev_attr_tx_compressed.attr,
 394         NULL
 395 };
 396
 397
 398 static struct attribute_group netstat_group = {
 399         .name  = "statistics",
 400         .attrs  = netstat_attrs,
 401 };
 402
 403 #ifdef CONFIG_WIRELESS_EXT_SYSFS
 404 /* helper function that does all the locking etc for wireless stats */
 405 static ssize_t wireless_show(struct device *d, char *buf,
 406                              ssize_t (*format)(const struct iw_statistics *,
 407                                                char *))
 408 {
 409         struct net_device *dev = to_net_dev(d);
 410         const struct iw_statistics *iw;
 411         ssize_t ret = -EINVAL;
 412
 413         if (!rtnl_trylock())
 414                 return restart_syscall();
 415         if (dev_isalive(dev)) {
 416                 iw = get_wireless_stats(dev);
 417                 if (iw)
 418                         ret = (*format)(iw, buf);
 419         }
 420         rtnl_unlock();
 421
 422         return ret;
 423 }
 424
 425 /* show function template for wireless fields */
 426 #define WIRELESS_SHOW(name, field, format_string)                       \
 427 static ssize_t format_iw_##name(const struct iw_statistics *iw, char *buf) \
 428 {                                                                       \
 429         return sprintf(buf, format_string, iw->field);                  \
 430 }                                                                       \
 431 static ssize_t show_iw_##name(struct device *d,                         \
 432                               struct device_attribute *attr, char *buf) \
 433 {                                                                       \
 434         return wireless_show(d, buf, format_iw_##name);                 \
 435 }                                                                       \
 436 static DEVICE_ATTR(name, S_IRUGO, show_iw_##name, NULL)
 437
 438 WIRELESS_SHOW(status, status, fmt_hex);
 439 WIRELESS_SHOW(link, qual.qual, fmt_dec);
 440 WIRELESS_SHOW(level, qual.level, fmt_dec);
 441 WIRELESS_SHOW(noise, qual.noise, fmt_dec);
 442 WIRELESS_SHOW(nwid, discard.nwid, fmt_dec);
 443 WIRELESS_SHOW(crypt, discard.code, fmt_dec);
 444 WIRELESS_SHOW(fragment, discard.fragment, fmt_dec);
 445 WIRELESS_SHOW(misc, discard.misc, fmt_dec);
 446 WIRELESS_SHOW(retries, discard.retries, fmt_dec);
 447 WIRELESS_SHOW(beacon, miss.beacon, fmt_dec);
 448
 449 static struct attribute *wireless_attrs[] = {
 450         &dev_attr_status.attr,
 451         &dev_attr_link.attr,
 452         &dev_attr_level.attr,
 453         &dev_attr_noise.attr,
 454         &dev_attr_nwid.attr,
 455         &dev_attr_crypt.attr,
 456         &dev_attr_fragment.attr,
 457         &dev_attr_retries.attr,
 458         &dev_attr_misc.attr,
 459         &dev_attr_beacon.attr,
 460         NULL
 461 };
 462
 463 static struct attribute_group wireless_group = {
 464         .name = "wireless",
 465         .attrs = wireless_attrs,
 466 };
 467 #endif
 468
 469 #endif /* CONFIG_SYSFS */
 470
 471 #ifdef CONFIG_HOTPLUG
 472 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
 473 {
 474         struct net_device *dev = to_net_dev(d);
 475         int retval;
 476
 477         if (!net_eq(dev_net(dev), &init_net))
 478                 return 0;
 479
 480         /* pass interface to uevent. */
 481         retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
 482         if (retval)
 483                 goto exit;
 484
 485         /* pass ifindex to uevent.
 486          * ifindex is useful as it won't change (interface name may change)
 487          * and is what RtNetlink uses natively. */
 488         retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
 489
 490 exit:
 491         return retval;
 492 }
 493 #endif
 494
 495 /*
 496  *      netdev_release -- destroy and free a dead device.
 497  *      Called when last reference to device kobject is gone.
 498  */
 499 static void netdev_release(struct device *d)
 500 {
 501         struct net_device *dev = to_net_dev(d);
 502
 503         BUG_ON(dev->reg_state != NETREG_RELEASED);
 504
 505         kfree(dev->ifalias);
 506         kfree((char *)dev - dev->padded);
 507 }
 508
 509 static struct class net_class = {
 510         .name = "net",
 511         .dev_release = netdev_release,
 512 #ifdef CONFIG_SYSFS
 513         .dev_attrs = net_class_attributes,
 514 #endif /* CONFIG_SYSFS */
 515 #ifdef CONFIG_HOTPLUG
 516         .dev_uevent = netdev_uevent,
 517 #endif
 518 };
 519
 520 /* Delete sysfs entries but hold kobject reference until after all
 521  * netdev references are gone.
 522  */
 523 void netdev_unregister_kobject(struct net_device * net)
 524 {
 525         struct device *dev = &(net->dev);
 526
 527         kobject_get(&dev->kobj);
 528
 529         if (!net_eq(dev_net(net), &init_net))
 530                 return;
 531
 532         device_del(dev);
 533 }
 534
 535 /* Create sysfs entries for network device. */
 536 int netdev_register_kobject(struct net_device *net)
 537 {
 538         struct device *dev = &(net->dev);
 539         const struct attribute_group **groups = net->sysfs_groups;
 540
 541         dev->class = &net_class;
 542         dev->platform_data = net;
 543         dev->groups = groups;
 544
 545         dev_set_name(dev, "%s", net->name);
 546
 547 #ifdef CONFIG_SYSFS
 548         /* Allow for a device specific group */
 549         if (*groups)
 550                 groups++;
 551
 552         *groups++ = &netstat_group;
 553 #ifdef CONFIG_WIRELESS_EXT_SYSFS
 554         if (net->ieee80211_ptr)
 555                 *groups++ = &wireless_group;
 556 #ifdef CONFIG_WIRELESS_EXT
 557         else if (net->wireless_handlers)
 558                 *groups++ = &wireless_group;
 559 #endif
 560 #endif
 561 #endif /* CONFIG_SYSFS */
 562
 563         if (!net_eq(dev_net(net), &init_net))
 564                 return 0;
 565
 566         return device_add(dev);
 567 }
 568
 569 int netdev_class_create_file(struct class_attribute *class_attr)
 570 {
 571         return class_create_file(&net_class, class_attr);
 572 }
 573
 574 void netdev_class_remove_file(struct class_attribute *class_attr)
 575 {
 576         class_remove_file(&net_class, class_attr);
 577 }
 578
 579 EXPORT_SYMBOL(netdev_class_create_file);
 580 EXPORT_SYMBOL(netdev_class_remove_file);
 581
 582 void netdev_initialize_kobject(struct net_device *net)
 583 {
 584         struct device *device = &(net->dev);
 585         device_initialize(device);
 586 }
 587
 588 int netdev_kobject_init(void)
 589 {
 590         return class_register(&net_class);
 591 }