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