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