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 <net/sock.h>
  18 #include <linux/rtnetlink.h>
  19 #include <linux/wireless.h>
  20 #include <net/wext.h>
  21
  22 #include "net-sysfs.h"
  23
  24 #ifdef CONFIG_SYSFS
  25 static const char fmt_hex[] = "%#x\n";
  26 static const char fmt_long_hex[] = "%#lx\n";
  27 static const char fmt_dec[] = "%d\n";
  28 static const char fmt_ulong[] = "%lu\n";
  29
  30 static inline int dev_isalive(const struct net_device *dev)
  31 {
  32         return dev->reg_state <= NETREG_REGISTERED;
  33 }
  34
  35 /* use same locking rules as GIF* ioctl's */
  36 static ssize_t netdev_show(const struct device *dev,
  37                            struct device_attribute *attr, char *buf,
  38                            ssize_t (*format)(const struct net_device *, char *))
  39 {
  40         struct net_device *net = to_net_dev(dev);
  41         ssize_t ret = -EINVAL;
  42
  43         read_lock(&dev_base_lock);
  44         if (dev_isalive(net))
  45                 ret = (*format)(net, buf);
  46         read_unlock(&dev_base_lock);
  47
  48         return ret;
  49 }
  50
  51 /* generate a show function for simple field */
  52 #define NETDEVICE_SHOW(field, format_string)                            \
  53 static ssize_t format_##field(const struct net_device *net, char *buf)  \
  54 {                                                                       \
  55         return sprintf(buf, format_string, net->field);                 \
  56 }                                                                       \
  57 static ssize_t show_##field(struct device *dev,                         \
  58                             struct device_attribute *attr, char *buf)   \
  59 {                                                                       \
  60         return netdev_show(dev, attr, buf, format_##field);             \
  61 }
  62
  63
  64 /* use same locking and permission rules as SIF* ioctl's */
  65 static ssize_t netdev_store(struct device *dev, struct device_attribute *attr,
  66                             const char *buf, size_t len,
  67                             int (*set)(struct net_device *, unsigned long))
  68 {
  69         struct net_device *net = to_net_dev(dev);
  70         char *endp;
  71         unsigned long new;
  72         int ret = -EINVAL;
  73
  74         if (!capable(CAP_NET_ADMIN))
  75                 return -EPERM;
  76
  77         new = simple_strtoul(buf, &endp, 0);
  78         if (endp == buf)
  79                 goto err;
  80
  81         if (!rtnl_trylock())
  82                 return restart_syscall();
  83
  84         if (dev_isalive(net)) {
  85                 if ((ret = (*set)(net, new)) == 0)
  86                         ret = len;
  87         }
  88         rtnl_unlock();
  89  err:
  90         return ret;
  91 }
  92
  93 NETDEVICE_SHOW(dev_id, fmt_hex);
  94 NETDEVICE_SHOW(addr_len, fmt_dec);
  95 NETDEVICE_SHOW(iflink, fmt_dec);
  96 NETDEVICE_SHOW(ifindex, fmt_dec);
  97 NETDEVICE_SHOW(features, fmt_long_hex);
  98 NETDEVICE_SHOW(type, fmt_dec);
  99 NETDEVICE_SHOW(link_mode, fmt_dec);
 100
 101 /* use same locking rules as GIFHWADDR ioctl's */
 102 static ssize_t show_address(struct device *dev, struct device_attribute *attr,
 103                             char *buf)
 104 {
 105         struct net_device *net = to_net_dev(dev);
 106         ssize_t ret = -EINVAL;
 107
 108         read_lock(&dev_base_lock);
 109         if (dev_isalive(net))
 110                 ret = sysfs_format_mac(buf, net->dev_addr, net->addr_len);
 111         read_unlock(&dev_base_lock);
 112         return ret;
 113 }
 114
 115 static ssize_t show_broadcast(struct device *dev,
 116                             struct device_attribute *attr, char *buf)
 117 {
 118         struct net_device *net = to_net_dev(dev);
 119         if (dev_isalive(net))
 120                 return sysfs_format_mac(buf, net->broadcast, net->addr_len);
 121         return -EINVAL;
 122 }
 123
 124 static ssize_t show_carrier(struct device *dev,
 125                             struct device_attribute *attr, char *buf)
 126 {
 127         struct net_device *netdev = to_net_dev(dev);
 128         if (netif_running(netdev)) {
 129                 return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
 130         }
 131         return -EINVAL;
 132 }
 133
 134 static ssize_t show_speed(struct device *dev,
 135                           struct device_attribute *attr, char *buf)
 136 {
 137         struct net_device *netdev = to_net_dev(dev);
 138         int ret = -EINVAL;
 139
 140         if (!rtnl_trylock())
 141                 return restart_syscall();
 142
 143         if (netif_running(netdev) &&
 144             netdev->ethtool_ops &&
 145             netdev->ethtool_ops->get_settings) {
 146                 struct ethtool_cmd cmd = { ETHTOOL_GSET };
 147
 148                 if (!netdev->ethtool_ops->get_settings(netdev, &cmd))
 149                         ret = sprintf(buf, fmt_dec, ethtool_cmd_speed(&cmd));
 150         }
 151         rtnl_unlock();
 152         return ret;
 153 }
 154
 155 static ssize_t show_duplex(struct device *dev,
 156                            struct device_attribute *attr, char *buf)
 157 {
 158         struct net_device *netdev = to_net_dev(dev);
 159         int ret = -EINVAL;
 160
 161         if (!rtnl_trylock())
 162                 return restart_syscall();
 163
 164         if (netif_running(netdev) &&
 165             netdev->ethtool_ops &&
 166             netdev->ethtool_ops->get_settings) {
 167                 struct ethtool_cmd cmd = { ETHTOOL_GSET };
 168
 169                 if (!netdev->ethtool_ops->get_settings(netdev, &cmd))
 170                         ret = sprintf(buf, "%s\n", 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 static struct device_attribute net_class_attributes[] = {
 294         __ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
 295         __ATTR(dev_id, S_IRUGO, show_dev_id, NULL),
 296         __ATTR(ifalias, S_IRUGO | S_IWUSR, show_ifalias, store_ifalias),
 297         __ATTR(iflink, S_IRUGO, show_iflink, NULL),
 298         __ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
 299         __ATTR(features, S_IRUGO, show_features, NULL),
 300         __ATTR(type, S_IRUGO, show_type, NULL),
 301         __ATTR(link_mode, S_IRUGO, show_link_mode, NULL),
 302         __ATTR(address, S_IRUGO, show_address, NULL),
 303         __ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
 304         __ATTR(carrier, S_IRUGO, show_carrier, NULL),
 305         __ATTR(speed, S_IRUGO, show_speed, NULL),
 306         __ATTR(duplex, S_IRUGO, show_duplex, NULL),
 307         __ATTR(dormant, S_IRUGO, show_dormant, NULL),
 308         __ATTR(operstate, S_IRUGO, show_operstate, NULL),
 309         __ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
 310         __ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
 311         __ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
 312                store_tx_queue_len),
 313         {}
 314 };
 315
 316 /* Show a given an attribute in the statistics group */
 317 static ssize_t netstat_show(const struct device *d,
 318                             struct device_attribute *attr, char *buf,
 319                             unsigned long offset)
 320 {
 321         struct net_device *dev = to_net_dev(d);
 322         ssize_t ret = -EINVAL;
 323
 324         WARN_ON(offset > sizeof(struct net_device_stats) ||
 325                         offset % sizeof(unsigned long) != 0);
 326
 327         read_lock(&dev_base_lock);
 328         if (dev_isalive(dev)) {
 329                 const struct net_device_stats *stats = dev_get_stats(dev);
 330                 ret = sprintf(buf, fmt_ulong,
 331                               *(unsigned long *)(((u8 *) stats) + offset));
 332         }
 333         read_unlock(&dev_base_lock);
 334         return ret;
 335 }
 336
 337 /* generate a read-only statistics attribute */
 338 #define NETSTAT_ENTRY(name)                                             \
 339 static ssize_t show_##name(struct device *d,                            \
 340                            struct device_attribute *attr, char *buf)    \
 341 {                                                                       \
 342         return netstat_show(d, attr, buf,                               \
 343                             offsetof(struct net_device_stats, name));   \
 344 }                                                                       \
 345 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
 346
 347 NETSTAT_ENTRY(rx_packets);
 348 NETSTAT_ENTRY(tx_packets);
 349 NETSTAT_ENTRY(rx_bytes);
 350 NETSTAT_ENTRY(tx_bytes);
 351 NETSTAT_ENTRY(rx_errors);
 352 NETSTAT_ENTRY(tx_errors);
 353 NETSTAT_ENTRY(rx_dropped);
 354 NETSTAT_ENTRY(tx_dropped);
 355 NETSTAT_ENTRY(multicast);
 356 NETSTAT_ENTRY(collisions);
 357 NETSTAT_ENTRY(rx_length_errors);
 358 NETSTAT_ENTRY(rx_over_errors);
 359 NETSTAT_ENTRY(rx_crc_errors);
 360 NETSTAT_ENTRY(rx_frame_errors);
 361 NETSTAT_ENTRY(rx_fifo_errors);
 362 NETSTAT_ENTRY(rx_missed_errors);
 363 NETSTAT_ENTRY(tx_aborted_errors);
 364 NETSTAT_ENTRY(tx_carrier_errors);
 365 NETSTAT_ENTRY(tx_fifo_errors);
 366 NETSTAT_ENTRY(tx_heartbeat_errors);
 367 NETSTAT_ENTRY(tx_window_errors);
 368 NETSTAT_ENTRY(rx_compressed);
 369 NETSTAT_ENTRY(tx_compressed);
 370
 371 static struct attribute *netstat_attrs[] = {
 372         &dev_attr_rx_packets.attr,
 373         &dev_attr_tx_packets.attr,
 374         &dev_attr_rx_bytes.attr,
 375         &dev_attr_tx_bytes.attr,
 376         &dev_attr_rx_errors.attr,
 377         &dev_attr_tx_errors.attr,
 378         &dev_attr_rx_dropped.attr,
 379         &dev_attr_tx_dropped.attr,
 380         &dev_attr_multicast.attr,
 381         &dev_attr_collisions.attr,
 382         &dev_attr_rx_length_errors.attr,
 383         &dev_attr_rx_over_errors.attr,
 384         &dev_attr_rx_crc_errors.attr,
 385         &dev_attr_rx_frame_errors.attr,
 386         &dev_attr_rx_fifo_errors.attr,
 387         &dev_attr_rx_missed_errors.attr,
 388         &dev_attr_tx_aborted_errors.attr,
 389         &dev_attr_tx_carrier_errors.attr,
 390         &dev_attr_tx_fifo_errors.attr,
 391         &dev_attr_tx_heartbeat_errors.attr,
 392         &dev_attr_tx_window_errors.attr,
 393         &dev_attr_rx_compressed.attr,
 394         &dev_attr_tx_compressed.attr,
 395         NULL
 396 };
 397
 398
 399 static struct attribute_group netstat_group = {
 400         .name  = "statistics",
 401         .attrs  = netstat_attrs,
 402 };
 403
 404 #ifdef CONFIG_WIRELESS_EXT_SYSFS
 405 /* helper function that does all the locking etc for wireless stats */
 406 static ssize_t wireless_show(struct device *d, char *buf,
 407                              ssize_t (*format)(const struct iw_statistics *,
 408                                                char *))
 409 {
 410         struct net_device *dev = to_net_dev(d);
 411         const struct iw_statistics *iw;
 412         ssize_t ret = -EINVAL;
 413
 414         if (!rtnl_trylock())
 415                 return restart_syscall();
 416         if (dev_isalive(dev)) {
 417                 iw = get_wireless_stats(dev);
 418                 if (iw)
 419                         ret = (*format)(iw, buf);
 420         }
 421         rtnl_unlock();
 422
 423         return ret;
 424 }
 425
 426 /* show function template for wireless fields */
 427 #define WIRELESS_SHOW(name, field, format_string)                       \
 428 static ssize_t format_iw_##name(const struct iw_statistics *iw, char *buf) \
 429 {                                                                       \
 430         return sprintf(buf, format_string, iw->field);                  \
 431 }                                                                       \
 432 static ssize_t show_iw_##name(struct device *d,                         \
 433                               struct device_attribute *attr, char *buf) \
 434 {                                                                       \
 435         return wireless_show(d, buf, format_iw_##name);                 \
 436 }                                                                       \
 437 static DEVICE_ATTR(name, S_IRUGO, show_iw_##name, NULL)
 438
 439 WIRELESS_SHOW(status, status, fmt_hex);
 440 WIRELESS_SHOW(link, qual.qual, fmt_dec);
 441 WIRELESS_SHOW(level, qual.level, fmt_dec);
 442 WIRELESS_SHOW(noise, qual.noise, fmt_dec);
 443 WIRELESS_SHOW(nwid, discard.nwid, fmt_dec);
 444 WIRELESS_SHOW(crypt, discard.code, fmt_dec);
 445 WIRELESS_SHOW(fragment, discard.fragment, fmt_dec);
 446 WIRELESS_SHOW(misc, discard.misc, fmt_dec);
 447 WIRELESS_SHOW(retries, discard.retries, fmt_dec);
 448 WIRELESS_SHOW(beacon, miss.beacon, fmt_dec);
 449
 450 static struct attribute *wireless_attrs[] = {
 451         &dev_attr_status.attr,
 452         &dev_attr_link.attr,
 453         &dev_attr_level.attr,
 454         &dev_attr_noise.attr,
 455         &dev_attr_nwid.attr,
 456         &dev_attr_crypt.attr,
 457         &dev_attr_fragment.attr,
 458         &dev_attr_retries.attr,
 459         &dev_attr_misc.attr,
 460         &dev_attr_beacon.attr,
 461         NULL
 462 };
 463
 464 static struct attribute_group wireless_group = {
 465         .name = "wireless",
 466         .attrs = wireless_attrs,
 467 };
 468 #endif
 469
 470 #endif /* CONFIG_SYSFS */
 471
 472 #ifdef CONFIG_HOTPLUG
 473 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
 474 {
 475         struct net_device *dev = to_net_dev(d);
 476         int retval;
 477
 478         if (!net_eq(dev_net(dev), &init_net))
 479                 return 0;
 480
 481         /* pass interface to uevent. */
 482         retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
 483         if (retval)
 484                 goto exit;
 485
 486         /* pass ifindex to uevent.
 487          * ifindex is useful as it won't change (interface name may change)
 488          * and is what RtNetlink uses natively. */
 489         retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
 490
 491 exit:
 492         return retval;
 493 }
 494 #endif
 495
 496 /*
 497  *      netdev_release -- destroy and free a dead device.
 498  *      Called when last reference to device kobject is gone.
 499  */
 500 static void netdev_release(struct device *d)
 501 {
 502         struct net_device *dev = to_net_dev(d);
 503
 504         BUG_ON(dev->reg_state != NETREG_RELEASED);
 505
 506         kfree(dev->ifalias);
 507         kfree((char *)dev - dev->padded);
 508 }
 509
 510 static struct class net_class = {
 511         .name = "net",
 512         .dev_release = netdev_release,
 513 #ifdef CONFIG_SYSFS
 514         .dev_attrs = net_class_attributes,
 515 #endif /* CONFIG_SYSFS */
 516 #ifdef CONFIG_HOTPLUG
 517         .dev_uevent = netdev_uevent,
 518 #endif
 519 };
 520
 521 /* Delete sysfs entries but hold kobject reference until after all
 522  * netdev references are gone.
 523  */
 524 void netdev_unregister_kobject(struct net_device * net)
 525 {
 526         struct device *dev = &(net->dev);
 527
 528         kobject_get(&dev->kobj);
 529
 530         if (!net_eq(dev_net(net), &init_net))
 531                 return;
 532
 533         device_del(dev);
 534 }
 535
 536 /* Create sysfs entries for network device. */
 537 int netdev_register_kobject(struct net_device *net)
 538 {
 539         struct device *dev = &(net->dev);
 540         const struct attribute_group **groups = net->sysfs_groups;
 541
 542         dev->class = &net_class;
 543         dev->platform_data = net;
 544         dev->groups = groups;
 545
 546         dev_set_name(dev, "%s", net->name);
 547
 548 #ifdef CONFIG_SYSFS
 549         /* Allow for a device specific group */
 550         if (*groups)
 551                 groups++;
 552
 553         *groups++ = &netstat_group;
 554 #ifdef CONFIG_WIRELESS_EXT_SYSFS
 555         if (net->ieee80211_ptr)
 556                 *groups++ = &wireless_group;
 557 #ifdef CONFIG_WIRELESS_EXT
 558         else if (net->wireless_handlers)
 559                 *groups++ = &wireless_group;
 560 #endif
 561 #endif
 562 #endif /* CONFIG_SYSFS */
 563
 564         if (!net_eq(dev_net(net), &init_net))
 565                 return 0;
 566
 567         return device_add(dev);
 568 }
 569
 570 int netdev_class_create_file(struct class_attribute *class_attr)
 571 {
 572         return class_create_file(&net_class, class_attr);
 573 }
 574
 575 void netdev_class_remove_file(struct class_attribute *class_attr)
 576 {
 577         class_remove_file(&net_class, class_attr);
 578 }
 579
 580 EXPORT_SYMBOL(netdev_class_create_file);
 581 EXPORT_SYMBOL(netdev_class_remove_file);
 582
 583 void netdev_initialize_kobject(struct net_device *net)
 584 {
 585         struct device *device = &(net->dev);
 586         device_initialize(device);
 587 }
 588
 589 int netdev_kobject_init(void)
 590 {
 591         return class_register(&net_class);
 592 }