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