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 NETDEVICE_SHOW(weight, fmt_dec);
 220
 221 static int change_weight(struct net_device *net, unsigned long new_weight)
 222 {
 223         net->weight = new_weight;
 224         return 0;
 225 }
 226
 227 static ssize_t store_weight(struct device *dev, struct device_attribute *attr,
 228                             const char *buf, size_t len)
 229 {
 230         return netdev_store(dev, attr, buf, len, change_weight);
 231 }
 232
 233 static struct device_attribute net_class_attributes[] = {
 234         __ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
 235         __ATTR(iflink, S_IRUGO, show_iflink, NULL),
 236         __ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
 237         __ATTR(features, S_IRUGO, show_features, NULL),
 238         __ATTR(type, S_IRUGO, show_type, NULL),
 239         __ATTR(link_mode, S_IRUGO, show_link_mode, NULL),
 240         __ATTR(address, S_IRUGO, show_address, NULL),
 241         __ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
 242         __ATTR(carrier, S_IRUGO, show_carrier, NULL),
 243         __ATTR(dormant, S_IRUGO, show_dormant, NULL),
 244         __ATTR(operstate, S_IRUGO, show_operstate, NULL),
 245         __ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
 246         __ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
 247         __ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
 248                store_tx_queue_len),
 249         __ATTR(weight, S_IRUGO | S_IWUSR, show_weight, store_weight),
 250         {}
 251 };
 252
 253 /* Show a given an attribute in the statistics group */
 254 static ssize_t netstat_show(const struct device *d,
 255                             struct device_attribute *attr, char *buf,
 256                             unsigned long offset)
 257 {
 258         struct net_device *dev = to_net_dev(d);
 259         struct net_device_stats *stats;
 260         ssize_t ret = -EINVAL;
 261
 262         if (offset > sizeof(struct net_device_stats) ||
 263             offset % sizeof(unsigned long) != 0)
 264                 WARN_ON(1);
 265
 266         read_lock(&dev_base_lock);
 267         if (dev_isalive(dev) && dev->get_stats &&
 268             (stats = (*dev->get_stats)(dev)))
 269                 ret = sprintf(buf, fmt_ulong,
 270                               *(unsigned long *)(((u8 *) stats) + offset));
 271
 272         read_unlock(&dev_base_lock);
 273         return ret;
 274 }
 275
 276 /* generate a read-only statistics attribute */
 277 #define NETSTAT_ENTRY(name)                                             \
 278 static ssize_t show_##name(struct device *d,                            \
 279                            struct device_attribute *attr, char *buf)    \
 280 {                                                                       \
 281         return netstat_show(d, attr, buf,                               \
 282                             offsetof(struct net_device_stats, name));   \
 283 }                                                                       \
 284 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
 285
 286 NETSTAT_ENTRY(rx_packets);
 287 NETSTAT_ENTRY(tx_packets);
 288 NETSTAT_ENTRY(rx_bytes);
 289 NETSTAT_ENTRY(tx_bytes);
 290 NETSTAT_ENTRY(rx_errors);
 291 NETSTAT_ENTRY(tx_errors);
 292 NETSTAT_ENTRY(rx_dropped);
 293 NETSTAT_ENTRY(tx_dropped);
 294 NETSTAT_ENTRY(multicast);
 295 NETSTAT_ENTRY(collisions);
 296 NETSTAT_ENTRY(rx_length_errors);
 297 NETSTAT_ENTRY(rx_over_errors);
 298 NETSTAT_ENTRY(rx_crc_errors);
 299 NETSTAT_ENTRY(rx_frame_errors);
 300 NETSTAT_ENTRY(rx_fifo_errors);
 301 NETSTAT_ENTRY(rx_missed_errors);
 302 NETSTAT_ENTRY(tx_aborted_errors);
 303 NETSTAT_ENTRY(tx_carrier_errors);
 304 NETSTAT_ENTRY(tx_fifo_errors);
 305 NETSTAT_ENTRY(tx_heartbeat_errors);
 306 NETSTAT_ENTRY(tx_window_errors);
 307 NETSTAT_ENTRY(rx_compressed);
 308 NETSTAT_ENTRY(tx_compressed);
 309
 310 static struct attribute *netstat_attrs[] = {
 311         &dev_attr_rx_packets.attr,
 312         &dev_attr_tx_packets.attr,
 313         &dev_attr_rx_bytes.attr,
 314         &dev_attr_tx_bytes.attr,
 315         &dev_attr_rx_errors.attr,
 316         &dev_attr_tx_errors.attr,
 317         &dev_attr_rx_dropped.attr,
 318         &dev_attr_tx_dropped.attr,
 319         &dev_attr_multicast.attr,
 320         &dev_attr_collisions.attr,
 321         &dev_attr_rx_length_errors.attr,
 322         &dev_attr_rx_over_errors.attr,
 323         &dev_attr_rx_crc_errors.attr,
 324         &dev_attr_rx_frame_errors.attr,
 325         &dev_attr_rx_fifo_errors.attr,
 326         &dev_attr_rx_missed_errors.attr,
 327         &dev_attr_tx_aborted_errors.attr,
 328         &dev_attr_tx_carrier_errors.attr,
 329         &dev_attr_tx_fifo_errors.attr,
 330         &dev_attr_tx_heartbeat_errors.attr,
 331         &dev_attr_tx_window_errors.attr,
 332         &dev_attr_rx_compressed.attr,
 333         &dev_attr_tx_compressed.attr,
 334         NULL
 335 };
 336
 337
 338 static struct attribute_group netstat_group = {
 339         .name  = "statistics",
 340         .attrs  = netstat_attrs,
 341 };
 342
 343 #ifdef CONFIG_WIRELESS_EXT
 344 /* helper function that does all the locking etc for wireless stats */
 345 static ssize_t wireless_show(struct device *d, char *buf,
 346                              ssize_t (*format)(const struct iw_statistics *,
 347                                                char *))
 348 {
 349         struct net_device *dev = to_net_dev(d);
 350         const struct iw_statistics *iw = NULL;
 351         ssize_t ret = -EINVAL;
 352
 353         read_lock(&dev_base_lock);
 354         if (dev_isalive(dev)) {
 355                 if (dev->wireless_handlers &&
 356                     dev->wireless_handlers->get_wireless_stats)
 357                         iw = dev->wireless_handlers->get_wireless_stats(dev);
 358                 if (iw != NULL)
 359                         ret = (*format)(iw, buf);
 360         }
 361         read_unlock(&dev_base_lock);
 362
 363         return ret;
 364 }
 365
 366 /* show function template for wireless fields */
 367 #define WIRELESS_SHOW(name, field, format_string)                       \
 368 static ssize_t format_iw_##name(const struct iw_statistics *iw, char *buf) \
 369 {                                                                       \
 370         return sprintf(buf, format_string, iw->field);                  \
 371 }                                                                       \
 372 static ssize_t show_iw_##name(struct device *d,                         \
 373                               struct device_attribute *attr, char *buf) \
 374 {                                                                       \
 375         return wireless_show(d, buf, format_iw_##name);                 \
 376 }                                                                       \
 377 static DEVICE_ATTR(name, S_IRUGO, show_iw_##name, NULL)
 378
 379 WIRELESS_SHOW(status, status, fmt_hex);
 380 WIRELESS_SHOW(link, qual.qual, fmt_dec);
 381 WIRELESS_SHOW(level, qual.level, fmt_dec);
 382 WIRELESS_SHOW(noise, qual.noise, fmt_dec);
 383 WIRELESS_SHOW(nwid, discard.nwid, fmt_dec);
 384 WIRELESS_SHOW(crypt, discard.code, fmt_dec);
 385 WIRELESS_SHOW(fragment, discard.fragment, fmt_dec);
 386 WIRELESS_SHOW(misc, discard.misc, fmt_dec);
 387 WIRELESS_SHOW(retries, discard.retries, fmt_dec);
 388 WIRELESS_SHOW(beacon, miss.beacon, fmt_dec);
 389
 390 static struct attribute *wireless_attrs[] = {
 391         &dev_attr_status.attr,
 392         &dev_attr_link.attr,
 393         &dev_attr_level.attr,
 394         &dev_attr_noise.attr,
 395         &dev_attr_nwid.attr,
 396         &dev_attr_crypt.attr,
 397         &dev_attr_fragment.attr,
 398         &dev_attr_retries.attr,
 399         &dev_attr_misc.attr,
 400         &dev_attr_beacon.attr,
 401         NULL
 402 };
 403
 404 static struct attribute_group wireless_group = {
 405         .name = "wireless",
 406         .attrs = wireless_attrs,
 407 };
 408 #endif
 409
 410 #ifdef CONFIG_HOTPLUG
 411 static int netdev_uevent(struct device *d, char **envp,
 412                          int num_envp, char *buf, int size)
 413 {
 414         struct net_device *dev = to_net_dev(d);
 415         int retval, len = 0, i = 0;
 416
 417         /* pass interface to uevent. */
 418         retval = add_uevent_var(envp, num_envp, &i,
 419                                 buf, size, &len,
 420                                 "INTERFACE=%s", dev->name);
 421         if (retval)
 422                 goto exit;
 423
 424         /* pass ifindex to uevent.
 425          * ifindex is useful as it won't change (interface name may change)
 426          * and is what RtNetlink uses natively. */
 427         retval = add_uevent_var(envp, num_envp, &i,
 428                                 buf, size, &len,
 429                                 "IFINDEX=%d", dev->ifindex);
 430
 431 exit:
 432         envp[i] = NULL;
 433         return retval;
 434 }
 435 #endif
 436
 437 /*
 438  *      netdev_release -- destroy and free a dead device.
 439  *      Called when last reference to device kobject is gone.
 440  */
 441 static void netdev_release(struct device *d)
 442 {
 443         struct net_device *dev = to_net_dev(d);
 444
 445         BUG_ON(dev->reg_state != NETREG_RELEASED);
 446
 447         kfree((char *)dev - dev->padded);
 448 }
 449
 450 static struct class net_class = {
 451         .name = "net",
 452         .dev_release = netdev_release,
 453         .dev_attrs = net_class_attributes,
 454 #ifdef CONFIG_HOTPLUG
 455         .dev_uevent = netdev_uevent,
 456 #endif
 457 };
 458
 459 /* Delete sysfs entries but hold kobject reference until after all
 460  * netdev references are gone.
 461  */
 462 void netdev_unregister_sysfs(struct net_device * net)
 463 {
 464         struct device *dev = &(net->dev);
 465
 466         kobject_get(&dev->kobj);
 467         device_del(dev);
 468 }
 469
 470 /* Create sysfs entries for network device. */
 471 int netdev_register_sysfs(struct net_device *net)
 472 {
 473         struct device *dev = &(net->dev);
 474         struct attribute_group **groups = net->sysfs_groups;
 475
 476         device_initialize(dev);
 477         dev->class = &net_class;
 478         dev->platform_data = net;
 479         dev->groups = groups;
 480
 481         BUILD_BUG_ON(BUS_ID_SIZE < IFNAMSIZ);
 482         strlcpy(dev->bus_id, net->name, BUS_ID_SIZE);
 483
 484         if (net->get_stats)
 485                 *groups++ = &netstat_group;
 486
 487 #ifdef CONFIG_WIRELESS_EXT
 488         if (net->wireless_handlers && net->wireless_handlers->get_wireless_stats)
 489                 *groups++ = &wireless_group;
 490 #endif
 491
 492         return device_add(dev);
 493 }
 494
 495 int netdev_sysfs_init(void)
 496 {
 497         return class_register(&net_class);
 498 }