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 #ifdef CONFIG_SYSFS
  22 static const char fmt_hex[] = "%#x\n";
  23 static const char fmt_long_hex[] = "%#lx\n";
  24 static const char fmt_dec[] = "%d\n";
  25 static const char fmt_ulong[] = "%lu\n";
  26
  27 static inline int dev_isalive(const struct net_device *dev)
  28 {
  29         return dev->reg_state <= NETREG_REGISTERED;
  30 }
  31
  32 /* use same locking rules as GIF* ioctl's */
  33 static ssize_t netdev_show(const struct device *dev,
  34                            struct device_attribute *attr, char *buf,
  35                            ssize_t (*format)(const struct net_device *, char *))
  36 {
  37         struct net_device *net = to_net_dev(dev);
  38         ssize_t ret = -EINVAL;
  39
  40         read_lock(&dev_base_lock);
  41         if (dev_isalive(net))
  42                 ret = (*format)(net, buf);
  43         read_unlock(&dev_base_lock);
  44
  45         return ret;
  46 }
  47
  48 /* generate a show function for simple field */
  49 #define NETDEVICE_SHOW(field, format_string)                            \
  50 static ssize_t format_##field(const struct net_device *net, char *buf)  \
  51 {                                                                       \
  52         return sprintf(buf, format_string, net->field);                 \
  53 }                                                                       \
  54 static ssize_t show_##field(struct device *dev,                         \
  55                             struct device_attribute *attr, char *buf)   \
  56 {                                                                       \
  57         return netdev_show(dev, attr, buf, format_##field);             \
  58 }
  59
  60
  61 /* use same locking and permission rules as SIF* ioctl's */
  62 static ssize_t netdev_store(struct device *dev, struct device_attribute *attr,
  63                             const char *buf, size_t len,
  64                             int (*set)(struct net_device *, unsigned long))
  65 {
  66         struct net_device *net = to_net_dev(dev);
  67         char *endp;
  68         unsigned long new;
  69         int ret = -EINVAL;
  70
  71         if (!capable(CAP_NET_ADMIN))
  72                 return -EPERM;
  73
  74         new = simple_strtoul(buf, &endp, 0);
  75         if (endp == buf)
  76                 goto err;
  77
  78         rtnl_lock();
  79         if (dev_isalive(net)) {
  80                 if ((ret = (*set)(net, new)) == 0)
  81                         ret = len;
  82         }
  83         rtnl_unlock();
  84  err:
  85         return ret;
  86 }
  87
  88 NETDEVICE_SHOW(addr_len, fmt_dec);
  89 NETDEVICE_SHOW(iflink, fmt_dec);
  90 NETDEVICE_SHOW(ifindex, fmt_dec);
  91 NETDEVICE_SHOW(features, fmt_long_hex);
  92 NETDEVICE_SHOW(type, fmt_dec);
  93 NETDEVICE_SHOW(link_mode, fmt_dec);
  94
  95 /* use same locking rules as GIFHWADDR ioctl's */
  96 static ssize_t format_addr(char *buf, const unsigned char *addr, int len)
  97 {
  98         int i;
  99         char *cp = buf;
 100
 101         for (i = 0; i < len; i++)
 102                 cp += sprintf(cp, "%02x%c", addr[i],
 103                               i == (len - 1) ? '\n' : ':');
 104         return cp - buf;
 105 }
 106
 107 static ssize_t show_address(struct device *dev, struct device_attribute *attr,
 108                             char *buf)
 109 {
 110         struct net_device *net = to_net_dev(dev);
 111         ssize_t ret = -EINVAL;
 112
 113         read_lock(&dev_base_lock);
 114         if (dev_isalive(net))
 115             ret = format_addr(buf, net->dev_addr, net->addr_len);
 116         read_unlock(&dev_base_lock);
 117         return ret;
 118 }
 119
 120 static ssize_t show_broadcast(struct device *dev,
 121                             struct device_attribute *attr, char *buf)
 122 {
 123         struct net_device *net = to_net_dev(dev);
 124         if (dev_isalive(net))
 125                 return format_addr(buf, net->broadcast, net->addr_len);
 126         return -EINVAL;
 127 }
 128
 129 static ssize_t show_carrier(struct device *dev,
 130                             struct device_attribute *attr, char *buf)
 131 {
 132         struct net_device *netdev = to_net_dev(dev);
 133         if (netif_running(netdev)) {
 134                 return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
 135         }
 136         return -EINVAL;
 137 }
 138
 139 static ssize_t show_dormant(struct device *dev,
 140                             struct device_attribute *attr, char *buf)
 141 {
 142         struct net_device *netdev = to_net_dev(dev);
 143
 144         if (netif_running(netdev))
 145                 return sprintf(buf, fmt_dec, !!netif_dormant(netdev));
 146
 147         return -EINVAL;
 148 }
 149
 150 static const char *operstates[] = {
 151         "unknown",
 152         "notpresent", /* currently unused */
 153         "down",
 154         "lowerlayerdown",
 155         "testing", /* currently unused */
 156         "dormant",
 157         "up"
 158 };
 159
 160 static ssize_t show_operstate(struct device *dev,
 161                               struct device_attribute *attr, char *buf)
 162 {
 163         const struct net_device *netdev = to_net_dev(dev);
 164         unsigned char operstate;
 165
 166         read_lock(&dev_base_lock);
 167         operstate = netdev->operstate;
 168         if (!netif_running(netdev))
 169                 operstate = IF_OPER_DOWN;
 170         read_unlock(&dev_base_lock);
 171
 172         if (operstate >= ARRAY_SIZE(operstates))
 173                 return -EINVAL; /* should not happen */
 174
 175         return sprintf(buf, "%s\n", operstates[operstate]);
 176 }
 177
 178 /* read-write attributes */
 179 NETDEVICE_SHOW(mtu, fmt_dec);
 180
 181 static int change_mtu(struct net_device *net, unsigned long new_mtu)
 182 {
 183         return dev_set_mtu(net, (int) new_mtu);
 184 }
 185
 186 static ssize_t store_mtu(struct device *dev, struct device_attribute *attr,
 187                          const char *buf, size_t len)
 188 {
 189         return netdev_store(dev, attr, buf, len, change_mtu);
 190 }
 191
 192 NETDEVICE_SHOW(flags, fmt_hex);
 193
 194 static int change_flags(struct net_device *net, unsigned long new_flags)
 195 {
 196         return dev_change_flags(net, (unsigned) new_flags);
 197 }
 198
 199 static ssize_t store_flags(struct device *dev, struct device_attribute *attr,
 200                            const char *buf, size_t len)
 201 {
 202         return netdev_store(dev, attr, buf, len, change_flags);
 203 }
 204
 205 NETDEVICE_SHOW(tx_queue_len, fmt_ulong);
 206
 207 static int change_tx_queue_len(struct net_device *net, unsigned long new_len)
 208 {
 209         net->tx_queue_len = new_len;
 210         return 0;
 211 }
 212
 213 static ssize_t store_tx_queue_len(struct device *dev,
 214                                   struct device_attribute *attr,
 215                                   const char *buf, size_t len)
 216 {
 217         return netdev_store(dev, attr, buf, len, change_tx_queue_len);
 218 }
 219
 220 static struct device_attribute net_class_attributes[] = {
 221         __ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
 222         __ATTR(iflink, S_IRUGO, show_iflink, NULL),
 223         __ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
 224         __ATTR(features, S_IRUGO, show_features, NULL),
 225         __ATTR(type, S_IRUGO, show_type, NULL),
 226         __ATTR(link_mode, S_IRUGO, show_link_mode, NULL),
 227         __ATTR(address, S_IRUGO, show_address, NULL),
 228         __ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
 229         __ATTR(carrier, S_IRUGO, show_carrier, NULL),
 230         __ATTR(dormant, S_IRUGO, show_dormant, NULL),
 231         __ATTR(operstate, S_IRUGO, show_operstate, NULL),
 232         __ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
 233         __ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
 234         __ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
 235                store_tx_queue_len),
 236         {}
 237 };
 238
 239 /* Show a given an attribute in the statistics group */
 240 static ssize_t netstat_show(const struct device *d,
 241                             struct device_attribute *attr, char *buf,
 242                             unsigned long offset)
 243 {
 244         struct net_device *dev = to_net_dev(d);
 245         struct net_device_stats *stats;
 246         ssize_t ret = -EINVAL;
 247
 248         if (offset > sizeof(struct net_device_stats) ||
 249             offset % sizeof(unsigned long) != 0)
 250                 WARN_ON(1);
 251
 252         read_lock(&dev_base_lock);
 253         if (dev_isalive(dev) && dev->get_stats &&
 254             (stats = (*dev->get_stats)(dev)))
 255                 ret = sprintf(buf, fmt_ulong,
 256                               *(unsigned long *)(((u8 *) stats) + offset));
 257
 258         read_unlock(&dev_base_lock);
 259         return ret;
 260 }
 261
 262 /* generate a read-only statistics attribute */
 263 #define NETSTAT_ENTRY(name)                                             \
 264 static ssize_t show_##name(struct device *d,                            \
 265                            struct device_attribute *attr, char *buf)    \
 266 {                                                                       \
 267         return netstat_show(d, attr, buf,                               \
 268                             offsetof(struct net_device_stats, name));   \
 269 }                                                                       \
 270 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
 271
 272 NETSTAT_ENTRY(rx_packets);
 273 NETSTAT_ENTRY(tx_packets);
 274 NETSTAT_ENTRY(rx_bytes);
 275 NETSTAT_ENTRY(tx_bytes);
 276 NETSTAT_ENTRY(rx_errors);
 277 NETSTAT_ENTRY(tx_errors);
 278 NETSTAT_ENTRY(rx_dropped);
 279 NETSTAT_ENTRY(tx_dropped);
 280 NETSTAT_ENTRY(multicast);
 281 NETSTAT_ENTRY(collisions);
 282 NETSTAT_ENTRY(rx_length_errors);
 283 NETSTAT_ENTRY(rx_over_errors);
 284 NETSTAT_ENTRY(rx_crc_errors);
 285 NETSTAT_ENTRY(rx_frame_errors);
 286 NETSTAT_ENTRY(rx_fifo_errors);
 287 NETSTAT_ENTRY(rx_missed_errors);
 288 NETSTAT_ENTRY(tx_aborted_errors);
 289 NETSTAT_ENTRY(tx_carrier_errors);
 290 NETSTAT_ENTRY(tx_fifo_errors);
 291 NETSTAT_ENTRY(tx_heartbeat_errors);
 292 NETSTAT_ENTRY(tx_window_errors);
 293 NETSTAT_ENTRY(rx_compressed);
 294 NETSTAT_ENTRY(tx_compressed);
 295
 296 static struct attribute *netstat_attrs[] = {
 297         &dev_attr_rx_packets.attr,
 298         &dev_attr_tx_packets.attr,
 299         &dev_attr_rx_bytes.attr,
 300         &dev_attr_tx_bytes.attr,
 301         &dev_attr_rx_errors.attr,
 302         &dev_attr_tx_errors.attr,
 303         &dev_attr_rx_dropped.attr,
 304         &dev_attr_tx_dropped.attr,
 305         &dev_attr_multicast.attr,
 306         &dev_attr_collisions.attr,
 307         &dev_attr_rx_length_errors.attr,
 308         &dev_attr_rx_over_errors.attr,
 309         &dev_attr_rx_crc_errors.attr,
 310         &dev_attr_rx_frame_errors.attr,
 311         &dev_attr_rx_fifo_errors.attr,
 312         &dev_attr_rx_missed_errors.attr,
 313         &dev_attr_tx_aborted_errors.attr,
 314         &dev_attr_tx_carrier_errors.attr,
 315         &dev_attr_tx_fifo_errors.attr,
 316         &dev_attr_tx_heartbeat_errors.attr,
 317         &dev_attr_tx_window_errors.attr,
 318         &dev_attr_rx_compressed.attr,
 319         &dev_attr_tx_compressed.attr,
 320         NULL
 321 };
 322
 323
 324 static struct attribute_group netstat_group = {
 325         .name  = "statistics",
 326         .attrs  = netstat_attrs,
 327 };
 328
 329 #ifdef CONFIG_WIRELESS_EXT
 330 /* helper function that does all the locking etc for wireless stats */
 331 static ssize_t wireless_show(struct device *d, char *buf,
 332                              ssize_t (*format)(const struct iw_statistics *,
 333                                                char *))
 334 {
 335         struct net_device *dev = to_net_dev(d);
 336         const struct iw_statistics *iw = NULL;
 337         ssize_t ret = -EINVAL;
 338
 339         read_lock(&dev_base_lock);
 340         if (dev_isalive(dev)) {
 341                 if (dev->wireless_handlers &&
 342                     dev->wireless_handlers->get_wireless_stats)
 343                         iw = dev->wireless_handlers->get_wireless_stats(dev);
 344                 if (iw != NULL)
 345                         ret = (*format)(iw, buf);
 346         }
 347         read_unlock(&dev_base_lock);
 348
 349         return ret;
 350 }
 351
 352 /* show function template for wireless fields */
 353 #define WIRELESS_SHOW(name, field, format_string)                       \
 354 static ssize_t format_iw_##name(const struct iw_statistics *iw, char *buf) \
 355 {                                                                       \
 356         return sprintf(buf, format_string, iw->field);                  \
 357 }                                                                       \
 358 static ssize_t show_iw_##name(struct device *d,                         \
 359                               struct device_attribute *attr, char *buf) \
 360 {                                                                       \
 361         return wireless_show(d, buf, format_iw_##name);                 \
 362 }                                                                       \
 363 static DEVICE_ATTR(name, S_IRUGO, show_iw_##name, NULL)
 364
 365 WIRELESS_SHOW(status, status, fmt_hex);
 366 WIRELESS_SHOW(link, qual.qual, fmt_dec);
 367 WIRELESS_SHOW(level, qual.level, fmt_dec);
 368 WIRELESS_SHOW(noise, qual.noise, fmt_dec);
 369 WIRELESS_SHOW(nwid, discard.nwid, fmt_dec);
 370 WIRELESS_SHOW(crypt, discard.code, fmt_dec);
 371 WIRELESS_SHOW(fragment, discard.fragment, fmt_dec);
 372 WIRELESS_SHOW(misc, discard.misc, fmt_dec);
 373 WIRELESS_SHOW(retries, discard.retries, fmt_dec);
 374 WIRELESS_SHOW(beacon, miss.beacon, fmt_dec);
 375
 376 static struct attribute *wireless_attrs[] = {
 377         &dev_attr_status.attr,
 378         &dev_attr_link.attr,
 379         &dev_attr_level.attr,
 380         &dev_attr_noise.attr,
 381         &dev_attr_nwid.attr,
 382         &dev_attr_crypt.attr,
 383         &dev_attr_fragment.attr,
 384         &dev_attr_retries.attr,
 385         &dev_attr_misc.attr,
 386         &dev_attr_beacon.attr,
 387         NULL
 388 };
 389
 390 static struct attribute_group wireless_group = {
 391         .name = "wireless",
 392         .attrs = wireless_attrs,
 393 };
 394 #endif
 395
 396 #endif /* CONFIG_SYSFS */
 397
 398 #ifdef CONFIG_HOTPLUG
 399 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
 400 {
 401         struct net_device *dev = to_net_dev(d);
 402         int retval;
 403
 404         /* pass interface to uevent. */
 405         retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
 406         if (retval)
 407                 goto exit;
 408
 409         /* pass ifindex to uevent.
 410          * ifindex is useful as it won't change (interface name may change)
 411          * and is what RtNetlink uses natively. */
 412         retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
 413
 414 exit:
 415         return retval;
 416 }
 417 #endif
 418
 419 /*
 420  *      netdev_release -- destroy and free a dead device.
 421  *      Called when last reference to device kobject is gone.
 422  */
 423 static void netdev_release(struct device *d)
 424 {
 425         struct net_device *dev = to_net_dev(d);
 426
 427         BUG_ON(dev->reg_state != NETREG_RELEASED);
 428
 429         kfree((char *)dev - dev->padded);
 430 }
 431
 432 static struct class net_class = {
 433         .name = "net",
 434         .dev_release = netdev_release,
 435 #ifdef CONFIG_SYSFS
 436         .dev_attrs = net_class_attributes,
 437 #endif /* CONFIG_SYSFS */
 438 #ifdef CONFIG_HOTPLUG
 439         .dev_uevent = netdev_uevent,
 440 #endif
 441 };
 442
 443 /* Delete sysfs entries but hold kobject reference until after all
 444  * netdev references are gone.
 445  */
 446 void netdev_unregister_kobject(struct net_device * net)
 447 {
 448         struct device *dev = &(net->dev);
 449
 450         kobject_get(&dev->kobj);
 451         device_del(dev);
 452 }
 453
 454 /* Create sysfs entries for network device. */
 455 int netdev_register_kobject(struct net_device *net)
 456 {
 457         struct device *dev = &(net->dev);
 458         struct attribute_group **groups = net->sysfs_groups;
 459
 460         device_initialize(dev);
 461         dev->class = &net_class;
 462         dev->platform_data = net;
 463         dev->groups = groups;
 464
 465         BUILD_BUG_ON(BUS_ID_SIZE < IFNAMSIZ);
 466         strlcpy(dev->bus_id, net->name, BUS_ID_SIZE);
 467
 468 #ifdef CONFIG_SYSFS
 469         if (net->get_stats)
 470                 *groups++ = &netstat_group;
 471
 472 #ifdef CONFIG_WIRELESS_EXT
 473         if (net->wireless_handlers && net->wireless_handlers->get_wireless_stats)
 474                 *groups++ = &wireless_group;
 475 #endif
 476 #endif /* CONFIG_SYSFS */
 477
 478         return device_add(dev);
 479 }
 480
 481 int netdev_kobject_init(void)
 482 {
 483         return class_register(&net_class);
 484 }