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