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(addr_len, fmt_dec);
  91 NETDEVICE_SHOW(iflink, fmt_dec);
  92 NETDEVICE_SHOW(ifindex, fmt_dec);
  93 NETDEVICE_SHOW(features, fmt_long_hex);
  94 NETDEVICE_SHOW(type, fmt_dec);
  95 NETDEVICE_SHOW(link_mode, fmt_dec);
  96
  97 /* use same locking rules as GIFHWADDR ioctl's */
  98 static ssize_t format_addr(char *buf, const unsigned char *addr, int len)
  99 {
 100         int i;
 101         char *cp = buf;
 102
 103         for (i = 0; i < len; i++)
 104                 cp += sprintf(cp, "%02x%c", addr[i],
 105                               i == (len - 1) ? '\n' : ':');
 106         return cp - buf;
 107 }
 108
 109 static ssize_t show_address(struct device *dev, struct device_attribute *attr,
 110                             char *buf)
 111 {
 112         struct net_device *net = to_net_dev(dev);
 113         ssize_t ret = -EINVAL;
 114
 115         read_lock(&dev_base_lock);
 116         if (dev_isalive(net))
 117             ret = format_addr(buf, net->dev_addr, net->addr_len);
 118         read_unlock(&dev_base_lock);
 119         return ret;
 120 }
 121
 122 static ssize_t show_broadcast(struct device *dev,
 123                             struct device_attribute *attr, char *buf)
 124 {
 125         struct net_device *net = to_net_dev(dev);
 126         if (dev_isalive(net))
 127                 return format_addr(buf, net->broadcast, net->addr_len);
 128         return -EINVAL;
 129 }
 130
 131 static ssize_t show_carrier(struct device *dev,
 132                             struct device_attribute *attr, char *buf)
 133 {
 134         struct net_device *netdev = to_net_dev(dev);
 135         if (netif_running(netdev)) {
 136                 return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
 137         }
 138         return -EINVAL;
 139 }
 140
 141 static ssize_t show_dormant(struct device *dev,
 142                             struct device_attribute *attr, char *buf)
 143 {
 144         struct net_device *netdev = to_net_dev(dev);
 145
 146         if (netif_running(netdev))
 147                 return sprintf(buf, fmt_dec, !!netif_dormant(netdev));
 148
 149         return -EINVAL;
 150 }
 151
 152 static const char *operstates[] = {
 153         "unknown",
 154         "notpresent", /* currently unused */
 155         "down",
 156         "lowerlayerdown",
 157         "testing", /* currently unused */
 158         "dormant",
 159         "up"
 160 };
 161
 162 static ssize_t show_operstate(struct device *dev,
 163                               struct device_attribute *attr, char *buf)
 164 {
 165         const struct net_device *netdev = to_net_dev(dev);
 166         unsigned char operstate;
 167
 168         read_lock(&dev_base_lock);
 169         operstate = netdev->operstate;
 170         if (!netif_running(netdev))
 171                 operstate = IF_OPER_DOWN;
 172         read_unlock(&dev_base_lock);
 173
 174         if (operstate >= ARRAY_SIZE(operstates))
 175                 return -EINVAL; /* should not happen */
 176
 177         return sprintf(buf, "%s\n", operstates[operstate]);
 178 }
 179
 180 /* read-write attributes */
 181 NETDEVICE_SHOW(mtu, fmt_dec);
 182
 183 static int change_mtu(struct net_device *net, unsigned long new_mtu)
 184 {
 185         return dev_set_mtu(net, (int) new_mtu);
 186 }
 187
 188 static ssize_t store_mtu(struct device *dev, struct device_attribute *attr,
 189                          const char *buf, size_t len)
 190 {
 191         return netdev_store(dev, attr, buf, len, change_mtu);
 192 }
 193
 194 NETDEVICE_SHOW(flags, fmt_hex);
 195
 196 static int change_flags(struct net_device *net, unsigned long new_flags)
 197 {
 198         return dev_change_flags(net, (unsigned) new_flags);
 199 }
 200
 201 static ssize_t store_flags(struct device *dev, struct device_attribute *attr,
 202                            const char *buf, size_t len)
 203 {
 204         return netdev_store(dev, attr, buf, len, change_flags);
 205 }
 206
 207 NETDEVICE_SHOW(tx_queue_len, fmt_ulong);
 208
 209 static int change_tx_queue_len(struct net_device *net, unsigned long new_len)
 210 {
 211         net->tx_queue_len = new_len;
 212         return 0;
 213 }
 214
 215 static ssize_t store_tx_queue_len(struct device *dev,
 216                                   struct device_attribute *attr,
 217                                   const char *buf, size_t len)
 218 {
 219         return netdev_store(dev, attr, buf, len, change_tx_queue_len);
 220 }
 221
 222 static struct device_attribute net_class_attributes[] = {
 223         __ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
 224         __ATTR(iflink, S_IRUGO, show_iflink, NULL),
 225         __ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
 226         __ATTR(features, S_IRUGO, show_features, NULL),
 227         __ATTR(type, S_IRUGO, show_type, NULL),
 228         __ATTR(link_mode, S_IRUGO, show_link_mode, NULL),
 229         __ATTR(address, S_IRUGO, show_address, NULL),
 230         __ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
 231         __ATTR(carrier, S_IRUGO, show_carrier, NULL),
 232         __ATTR(dormant, S_IRUGO, show_dormant, NULL),
 233         __ATTR(operstate, S_IRUGO, show_operstate, NULL),
 234         __ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
 235         __ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
 236         __ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
 237                store_tx_queue_len),
 238         {}
 239 };
 240
 241 /* Show a given an attribute in the statistics group */
 242 static ssize_t netstat_show(const struct device *d,
 243                             struct device_attribute *attr, char *buf,
 244                             unsigned long offset)
 245 {
 246         struct net_device *dev = to_net_dev(d);
 247         struct net_device_stats *stats;
 248         ssize_t ret = -EINVAL;
 249
 250         WARN_ON(offset > sizeof(struct net_device_stats) ||
 251                         offset % sizeof(unsigned long) != 0);
 252
 253         read_lock(&dev_base_lock);
 254         if (dev_isalive(dev) && dev->get_stats &&
 255             (stats = (*dev->get_stats)(dev)))
 256                 ret = sprintf(buf, fmt_ulong,
 257                               *(unsigned long *)(((u8 *) stats) + offset));
 258
 259         read_unlock(&dev_base_lock);
 260         return ret;
 261 }
 262
 263 /* generate a read-only statistics attribute */
 264 #define NETSTAT_ENTRY(name)                                             \
 265 static ssize_t show_##name(struct device *d,                            \
 266                            struct device_attribute *attr, char *buf)    \
 267 {                                                                       \
 268         return netstat_show(d, attr, buf,                               \
 269                             offsetof(struct net_device_stats, name));   \
 270 }                                                                       \
 271 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
 272
 273 NETSTAT_ENTRY(rx_packets);
 274 NETSTAT_ENTRY(tx_packets);
 275 NETSTAT_ENTRY(rx_bytes);
 276 NETSTAT_ENTRY(tx_bytes);
 277 NETSTAT_ENTRY(rx_errors);
 278 NETSTAT_ENTRY(tx_errors);
 279 NETSTAT_ENTRY(rx_dropped);
 280 NETSTAT_ENTRY(tx_dropped);
 281 NETSTAT_ENTRY(multicast);
 282 NETSTAT_ENTRY(collisions);
 283 NETSTAT_ENTRY(rx_length_errors);
 284 NETSTAT_ENTRY(rx_over_errors);
 285 NETSTAT_ENTRY(rx_crc_errors);
 286 NETSTAT_ENTRY(rx_frame_errors);
 287 NETSTAT_ENTRY(rx_fifo_errors);
 288 NETSTAT_ENTRY(rx_missed_errors);
 289 NETSTAT_ENTRY(tx_aborted_errors);
 290 NETSTAT_ENTRY(tx_carrier_errors);
 291 NETSTAT_ENTRY(tx_fifo_errors);
 292 NETSTAT_ENTRY(tx_heartbeat_errors);
 293 NETSTAT_ENTRY(tx_window_errors);
 294 NETSTAT_ENTRY(rx_compressed);
 295 NETSTAT_ENTRY(tx_compressed);
 296
 297 static struct attribute *netstat_attrs[] = {
 298         &dev_attr_rx_packets.attr,
 299         &dev_attr_tx_packets.attr,
 300         &dev_attr_rx_bytes.attr,
 301         &dev_attr_tx_bytes.attr,
 302         &dev_attr_rx_errors.attr,
 303         &dev_attr_tx_errors.attr,
 304         &dev_attr_rx_dropped.attr,
 305         &dev_attr_tx_dropped.attr,
 306         &dev_attr_multicast.attr,
 307         &dev_attr_collisions.attr,
 308         &dev_attr_rx_length_errors.attr,
 309         &dev_attr_rx_over_errors.attr,
 310         &dev_attr_rx_crc_errors.attr,
 311         &dev_attr_rx_frame_errors.attr,
 312         &dev_attr_rx_fifo_errors.attr,
 313         &dev_attr_rx_missed_errors.attr,
 314         &dev_attr_tx_aborted_errors.attr,
 315         &dev_attr_tx_carrier_errors.attr,
 316         &dev_attr_tx_fifo_errors.attr,
 317         &dev_attr_tx_heartbeat_errors.attr,
 318         &dev_attr_tx_window_errors.attr,
 319         &dev_attr_rx_compressed.attr,
 320         &dev_attr_tx_compressed.attr,
 321         NULL
 322 };
 323
 324
 325 static struct attribute_group netstat_group = {
 326         .name  = "statistics",
 327         .attrs  = netstat_attrs,
 328 };
 329
 330 #ifdef CONFIG_WIRELESS_EXT
 331 /* helper function that does all the locking etc for wireless stats */
 332 static ssize_t wireless_show(struct device *d, char *buf,
 333                              ssize_t (*format)(const struct iw_statistics *,
 334                                                char *))
 335 {
 336         struct net_device *dev = to_net_dev(d);
 337         const struct iw_statistics *iw = NULL;
 338         ssize_t ret = -EINVAL;
 339
 340         read_lock(&dev_base_lock);
 341         if (dev_isalive(dev)) {
 342                 if (dev->wireless_handlers &&
 343                     dev->wireless_handlers->get_wireless_stats)
 344                         iw = dev->wireless_handlers->get_wireless_stats(dev);
 345                 if (iw != NULL)
 346                         ret = (*format)(iw, buf);
 347         }
 348         read_unlock(&dev_base_lock);
 349
 350         return ret;
 351 }
 352
 353 /* show function template for wireless fields */
 354 #define WIRELESS_SHOW(name, field, format_string)                       \
 355 static ssize_t format_iw_##name(const struct iw_statistics *iw, char *buf) \
 356 {                                                                       \
 357         return sprintf(buf, format_string, iw->field);                  \
 358 }                                                                       \
 359 static ssize_t show_iw_##name(struct device *d,                         \
 360                               struct device_attribute *attr, char *buf) \
 361 {                                                                       \
 362         return wireless_show(d, buf, format_iw_##name);                 \
 363 }                                                                       \
 364 static DEVICE_ATTR(name, S_IRUGO, show_iw_##name, NULL)
 365
 366 WIRELESS_SHOW(status, status, fmt_hex);
 367 WIRELESS_SHOW(link, qual.qual, fmt_dec);
 368 WIRELESS_SHOW(level, qual.level, fmt_dec);
 369 WIRELESS_SHOW(noise, qual.noise, fmt_dec);
 370 WIRELESS_SHOW(nwid, discard.nwid, fmt_dec);
 371 WIRELESS_SHOW(crypt, discard.code, fmt_dec);
 372 WIRELESS_SHOW(fragment, discard.fragment, fmt_dec);
 373 WIRELESS_SHOW(misc, discard.misc, fmt_dec);
 374 WIRELESS_SHOW(retries, discard.retries, fmt_dec);
 375 WIRELESS_SHOW(beacon, miss.beacon, fmt_dec);
 376
 377 static struct attribute *wireless_attrs[] = {
 378         &dev_attr_status.attr,
 379         &dev_attr_link.attr,
 380         &dev_attr_level.attr,
 381         &dev_attr_noise.attr,
 382         &dev_attr_nwid.attr,
 383         &dev_attr_crypt.attr,
 384         &dev_attr_fragment.attr,
 385         &dev_attr_retries.attr,
 386         &dev_attr_misc.attr,
 387         &dev_attr_beacon.attr,
 388         NULL
 389 };
 390
 391 static struct attribute_group wireless_group = {
 392         .name = "wireless",
 393         .attrs = wireless_attrs,
 394 };
 395 #endif
 396
 397 #endif /* CONFIG_SYSFS */
 398
 399 #ifdef CONFIG_HOTPLUG
 400 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
 401 {
 402         struct net_device *dev = to_net_dev(d);
 403         int retval;
 404
 405         /* pass interface to uevent. */
 406         retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
 407         if (retval)
 408                 goto exit;
 409
 410         /* pass ifindex to uevent.
 411          * ifindex is useful as it won't change (interface name may change)
 412          * and is what RtNetlink uses natively. */
 413         retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
 414
 415 exit:
 416         return retval;
 417 }
 418 #endif
 419
 420 /*
 421  *      netdev_release -- destroy and free a dead device.
 422  *      Called when last reference to device kobject is gone.
 423  */
 424 static void netdev_release(struct device *d)
 425 {
 426         struct net_device *dev = to_net_dev(d);
 427
 428         BUG_ON(dev->reg_state != NETREG_RELEASED);
 429
 430         kfree((char *)dev - dev->padded);
 431 }
 432
 433 static struct class net_class = {
 434         .name = "net",
 435         .dev_release = netdev_release,
 436 #ifdef CONFIG_SYSFS
 437         .dev_attrs = net_class_attributes,
 438 #endif /* CONFIG_SYSFS */
 439 #ifdef CONFIG_HOTPLUG
 440         .dev_uevent = netdev_uevent,
 441 #endif
 442 };
 443
 444 /* Delete sysfs entries but hold kobject reference until after all
 445  * netdev references are gone.
 446  */
 447 void netdev_unregister_kobject(struct net_device * net)
 448 {
 449         struct device *dev = &(net->dev);
 450
 451         kobject_get(&dev->kobj);
 452         device_del(dev);
 453 }
 454
 455 /* Create sysfs entries for network device. */
 456 int netdev_register_kobject(struct net_device *net)
 457 {
 458         struct device *dev = &(net->dev);
 459         struct attribute_group **groups = net->sysfs_groups;
 460
 461         device_initialize(dev);
 462         dev->class = &net_class;
 463         dev->platform_data = net;
 464         dev->groups = groups;
 465
 466         BUILD_BUG_ON(BUS_ID_SIZE < IFNAMSIZ);
 467         strlcpy(dev->bus_id, net->name, BUS_ID_SIZE);
 468
 469 #ifdef CONFIG_SYSFS
 470         if (net->get_stats)
 471                 *groups++ = &netstat_group;
 472
 473 #ifdef CONFIG_WIRELESS_EXT
 474         if (net->wireless_handlers && net->wireless_handlers->get_wireless_stats)
 475                 *groups++ = &wireless_group;
 476 #endif
 477 #endif /* CONFIG_SYSFS */
 478
 479         return device_add(dev);
 480 }
 481
 482 int netdev_kobject_init(void)
 483 {
 484         return class_register(&net_class);
 485 }