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(dev_id, fmt_hex);
  91 NETDEVICE_SHOW(addr_len, fmt_dec);
  92 NETDEVICE_SHOW(iflink, fmt_dec);
  93 NETDEVICE_SHOW(ifindex, fmt_dec);
  94 NETDEVICE_SHOW(features, fmt_long_hex);
  95 NETDEVICE_SHOW(type, fmt_dec);
  96 NETDEVICE_SHOW(link_mode, fmt_dec);
  97
  98 /* use same locking rules as GIFHWADDR ioctl's */
  99 static ssize_t show_address(struct device *dev, struct device_attribute *attr,
 100                             char *buf)
 101 {
 102         struct net_device *net = to_net_dev(dev);
 103         ssize_t ret = -EINVAL;
 104
 105         read_lock(&dev_base_lock);
 106         if (dev_isalive(net))
 107                 ret = sysfs_format_mac(buf, net->dev_addr, net->addr_len);
 108         read_unlock(&dev_base_lock);
 109         return ret;
 110 }
 111
 112 static ssize_t show_broadcast(struct device *dev,
 113                             struct device_attribute *attr, char *buf)
 114 {
 115         struct net_device *net = to_net_dev(dev);
 116         if (dev_isalive(net))
 117                 return sysfs_format_mac(buf, net->broadcast, net->addr_len);
 118         return -EINVAL;
 119 }
 120
 121 static ssize_t show_carrier(struct device *dev,
 122                             struct device_attribute *attr, char *buf)
 123 {
 124         struct net_device *netdev = to_net_dev(dev);
 125         if (netif_running(netdev)) {
 126                 return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
 127         }
 128         return -EINVAL;
 129 }
 130
 131 static ssize_t show_dormant(struct device *dev,
 132                             struct device_attribute *attr, char *buf)
 133 {
 134         struct net_device *netdev = to_net_dev(dev);
 135
 136         if (netif_running(netdev))
 137                 return sprintf(buf, fmt_dec, !!netif_dormant(netdev));
 138
 139         return -EINVAL;
 140 }
 141
 142 static const char *operstates[] = {
 143         "unknown",
 144         "notpresent", /* currently unused */
 145         "down",
 146         "lowerlayerdown",
 147         "testing", /* currently unused */
 148         "dormant",
 149         "up"
 150 };
 151
 152 static ssize_t show_operstate(struct device *dev,
 153                               struct device_attribute *attr, char *buf)
 154 {
 155         const struct net_device *netdev = to_net_dev(dev);
 156         unsigned char operstate;
 157
 158         read_lock(&dev_base_lock);
 159         operstate = netdev->operstate;
 160         if (!netif_running(netdev))
 161                 operstate = IF_OPER_DOWN;
 162         read_unlock(&dev_base_lock);
 163
 164         if (operstate >= ARRAY_SIZE(operstates))
 165                 return -EINVAL; /* should not happen */
 166
 167         return sprintf(buf, "%s\n", operstates[operstate]);
 168 }
 169
 170 /* read-write attributes */
 171 NETDEVICE_SHOW(mtu, fmt_dec);
 172
 173 static int change_mtu(struct net_device *net, unsigned long new_mtu)
 174 {
 175         return dev_set_mtu(net, (int) new_mtu);
 176 }
 177
 178 static ssize_t store_mtu(struct device *dev, struct device_attribute *attr,
 179                          const char *buf, size_t len)
 180 {
 181         return netdev_store(dev, attr, buf, len, change_mtu);
 182 }
 183
 184 NETDEVICE_SHOW(flags, fmt_hex);
 185
 186 static int change_flags(struct net_device *net, unsigned long new_flags)
 187 {
 188         return dev_change_flags(net, (unsigned) new_flags);
 189 }
 190
 191 static ssize_t store_flags(struct device *dev, struct device_attribute *attr,
 192                            const char *buf, size_t len)
 193 {
 194         return netdev_store(dev, attr, buf, len, change_flags);
 195 }
 196
 197 NETDEVICE_SHOW(tx_queue_len, fmt_ulong);
 198
 199 static int change_tx_queue_len(struct net_device *net, unsigned long new_len)
 200 {
 201         net->tx_queue_len = new_len;
 202         return 0;
 203 }
 204
 205 static ssize_t store_tx_queue_len(struct device *dev,
 206                                   struct device_attribute *attr,
 207                                   const char *buf, size_t len)
 208 {
 209         return netdev_store(dev, attr, buf, len, change_tx_queue_len);
 210 }
 211
 212 static struct device_attribute net_class_attributes[] = {
 213         __ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
 214         __ATTR(dev_id, S_IRUGO, show_dev_id, NULL),
 215         __ATTR(iflink, S_IRUGO, show_iflink, NULL),
 216         __ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
 217         __ATTR(features, S_IRUGO, show_features, NULL),
 218         __ATTR(type, S_IRUGO, show_type, NULL),
 219         __ATTR(link_mode, S_IRUGO, show_link_mode, NULL),
 220         __ATTR(address, S_IRUGO, show_address, NULL),
 221         __ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
 222         __ATTR(carrier, S_IRUGO, show_carrier, NULL),
 223         __ATTR(dormant, S_IRUGO, show_dormant, NULL),
 224         __ATTR(operstate, S_IRUGO, show_operstate, NULL),
 225         __ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
 226         __ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
 227         __ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
 228                store_tx_queue_len),
 229         {}
 230 };
 231
 232 /* Show a given an attribute in the statistics group */
 233 static ssize_t netstat_show(const struct device *d,
 234                             struct device_attribute *attr, char *buf,
 235                             unsigned long offset)
 236 {
 237         struct net_device *dev = to_net_dev(d);
 238         struct net_device_stats *stats;
 239         ssize_t ret = -EINVAL;
 240
 241         WARN_ON(offset > sizeof(struct net_device_stats) ||
 242                         offset % sizeof(unsigned long) != 0);
 243
 244         read_lock(&dev_base_lock);
 245         if (dev_isalive(dev)) {
 246                 stats = dev->get_stats(dev);
 247                 ret = sprintf(buf, fmt_ulong,
 248                               *(unsigned long *)(((u8 *) stats) + offset));
 249         }
 250         read_unlock(&dev_base_lock);
 251         return ret;
 252 }
 253
 254 /* generate a read-only statistics attribute */
 255 #define NETSTAT_ENTRY(name)                                             \
 256 static ssize_t show_##name(struct device *d,                            \
 257                            struct device_attribute *attr, char *buf)    \
 258 {                                                                       \
 259         return netstat_show(d, attr, buf,                               \
 260                             offsetof(struct net_device_stats, name));   \
 261 }                                                                       \
 262 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
 263
 264 NETSTAT_ENTRY(rx_packets);
 265 NETSTAT_ENTRY(tx_packets);
 266 NETSTAT_ENTRY(rx_bytes);
 267 NETSTAT_ENTRY(tx_bytes);
 268 NETSTAT_ENTRY(rx_errors);
 269 NETSTAT_ENTRY(tx_errors);
 270 NETSTAT_ENTRY(rx_dropped);
 271 NETSTAT_ENTRY(tx_dropped);
 272 NETSTAT_ENTRY(multicast);
 273 NETSTAT_ENTRY(collisions);
 274 NETSTAT_ENTRY(rx_length_errors);
 275 NETSTAT_ENTRY(rx_over_errors);
 276 NETSTAT_ENTRY(rx_crc_errors);
 277 NETSTAT_ENTRY(rx_frame_errors);
 278 NETSTAT_ENTRY(rx_fifo_errors);
 279 NETSTAT_ENTRY(rx_missed_errors);
 280 NETSTAT_ENTRY(tx_aborted_errors);
 281 NETSTAT_ENTRY(tx_carrier_errors);
 282 NETSTAT_ENTRY(tx_fifo_errors);
 283 NETSTAT_ENTRY(tx_heartbeat_errors);
 284 NETSTAT_ENTRY(tx_window_errors);
 285 NETSTAT_ENTRY(rx_compressed);
 286 NETSTAT_ENTRY(tx_compressed);
 287
 288 static struct attribute *netstat_attrs[] = {
 289         &dev_attr_rx_packets.attr,
 290         &dev_attr_tx_packets.attr,
 291         &dev_attr_rx_bytes.attr,
 292         &dev_attr_tx_bytes.attr,
 293         &dev_attr_rx_errors.attr,
 294         &dev_attr_tx_errors.attr,
 295         &dev_attr_rx_dropped.attr,
 296         &dev_attr_tx_dropped.attr,
 297         &dev_attr_multicast.attr,
 298         &dev_attr_collisions.attr,
 299         &dev_attr_rx_length_errors.attr,
 300         &dev_attr_rx_over_errors.attr,
 301         &dev_attr_rx_crc_errors.attr,
 302         &dev_attr_rx_frame_errors.attr,
 303         &dev_attr_rx_fifo_errors.attr,
 304         &dev_attr_rx_missed_errors.attr,
 305         &dev_attr_tx_aborted_errors.attr,
 306         &dev_attr_tx_carrier_errors.attr,
 307         &dev_attr_tx_fifo_errors.attr,
 308         &dev_attr_tx_heartbeat_errors.attr,
 309         &dev_attr_tx_window_errors.attr,
 310         &dev_attr_rx_compressed.attr,
 311         &dev_attr_tx_compressed.attr,
 312         NULL
 313 };
 314
 315
 316 static struct attribute_group netstat_group = {
 317         .name  = "statistics",
 318         .attrs  = netstat_attrs,
 319 };
 320
 321 #ifdef CONFIG_WIRELESS_EXT
 322 /* helper function that does all the locking etc for wireless stats */
 323 static ssize_t wireless_show(struct device *d, char *buf,
 324                              ssize_t (*format)(const struct iw_statistics *,
 325                                                char *))
 326 {
 327         struct net_device *dev = to_net_dev(d);
 328         const struct iw_statistics *iw = NULL;
 329         ssize_t ret = -EINVAL;
 330
 331         read_lock(&dev_base_lock);
 332         if (dev_isalive(dev)) {
 333                 if (dev->wireless_handlers &&
 334                     dev->wireless_handlers->get_wireless_stats)
 335                         iw = dev->wireless_handlers->get_wireless_stats(dev);
 336                 if (iw != NULL)
 337                         ret = (*format)(iw, buf);
 338         }
 339         read_unlock(&dev_base_lock);
 340
 341         return ret;
 342 }
 343
 344 /* show function template for wireless fields */
 345 #define WIRELESS_SHOW(name, field, format_string)                       \
 346 static ssize_t format_iw_##name(const struct iw_statistics *iw, char *buf) \
 347 {                                                                       \
 348         return sprintf(buf, format_string, iw->field);                  \
 349 }                                                                       \
 350 static ssize_t show_iw_##name(struct device *d,                         \
 351                               struct device_attribute *attr, char *buf) \
 352 {                                                                       \
 353         return wireless_show(d, buf, format_iw_##name);                 \
 354 }                                                                       \
 355 static DEVICE_ATTR(name, S_IRUGO, show_iw_##name, NULL)
 356
 357 WIRELESS_SHOW(status, status, fmt_hex);
 358 WIRELESS_SHOW(link, qual.qual, fmt_dec);
 359 WIRELESS_SHOW(level, qual.level, fmt_dec);
 360 WIRELESS_SHOW(noise, qual.noise, fmt_dec);
 361 WIRELESS_SHOW(nwid, discard.nwid, fmt_dec);
 362 WIRELESS_SHOW(crypt, discard.code, fmt_dec);
 363 WIRELESS_SHOW(fragment, discard.fragment, fmt_dec);
 364 WIRELESS_SHOW(misc, discard.misc, fmt_dec);
 365 WIRELESS_SHOW(retries, discard.retries, fmt_dec);
 366 WIRELESS_SHOW(beacon, miss.beacon, fmt_dec);
 367
 368 static struct attribute *wireless_attrs[] = {
 369         &dev_attr_status.attr,
 370         &dev_attr_link.attr,
 371         &dev_attr_level.attr,
 372         &dev_attr_noise.attr,
 373         &dev_attr_nwid.attr,
 374         &dev_attr_crypt.attr,
 375         &dev_attr_fragment.attr,
 376         &dev_attr_retries.attr,
 377         &dev_attr_misc.attr,
 378         &dev_attr_beacon.attr,
 379         NULL
 380 };
 381
 382 static struct attribute_group wireless_group = {
 383         .name = "wireless",
 384         .attrs = wireless_attrs,
 385 };
 386 #endif
 387
 388 #endif /* CONFIG_SYSFS */
 389
 390 #ifdef CONFIG_HOTPLUG
 391 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
 392 {
 393         struct net_device *dev = to_net_dev(d);
 394         int retval;
 395
 396         /* pass interface to uevent. */
 397         retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
 398         if (retval)
 399                 goto exit;
 400
 401         /* pass ifindex to uevent.
 402          * ifindex is useful as it won't change (interface name may change)
 403          * and is what RtNetlink uses natively. */
 404         retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
 405
 406 exit:
 407         return retval;
 408 }
 409 #endif
 410
 411 /*
 412  *      netdev_release -- destroy and free a dead device.
 413  *      Called when last reference to device kobject is gone.
 414  */
 415 static void netdev_release(struct device *d)
 416 {
 417         struct net_device *dev = to_net_dev(d);
 418
 419         BUG_ON(dev->reg_state != NETREG_RELEASED);
 420
 421         kfree((char *)dev - dev->padded);
 422 }
 423
 424 static struct class net_class = {
 425         .name = "net",
 426         .dev_release = netdev_release,
 427 #ifdef CONFIG_SYSFS
 428         .dev_attrs = net_class_attributes,
 429 #endif /* CONFIG_SYSFS */
 430 #ifdef CONFIG_HOTPLUG
 431         .dev_uevent = netdev_uevent,
 432 #endif
 433 };
 434
 435 /* Delete sysfs entries but hold kobject reference until after all
 436  * netdev references are gone.
 437  */
 438 void netdev_unregister_kobject(struct net_device * net)
 439 {
 440         struct device *dev = &(net->dev);
 441
 442         kobject_get(&dev->kobj);
 443         device_del(dev);
 444 }
 445
 446 /* Create sysfs entries for network device. */
 447 int netdev_register_kobject(struct net_device *net)
 448 {
 449         struct device *dev = &(net->dev);
 450         struct attribute_group **groups = net->sysfs_groups;
 451
 452         dev->class = &net_class;
 453         dev->platform_data = net;
 454         dev->groups = groups;
 455
 456         BUILD_BUG_ON(BUS_ID_SIZE < IFNAMSIZ);
 457         strlcpy(dev->bus_id, net->name, BUS_ID_SIZE);
 458
 459 #ifdef CONFIG_SYSFS
 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_class_create_file(struct class_attribute *class_attr)
 472 {
 473         return class_create_file(&net_class, class_attr);
 474 }
 475
 476 void netdev_class_remove_file(struct class_attribute *class_attr)
 477 {
 478         class_remove_file(&net_class, class_attr);
 479 }
 480
 481 EXPORT_SYMBOL(netdev_class_create_file);
 482 EXPORT_SYMBOL(netdev_class_remove_file);
 483
 484 void netdev_initialize_kobject(struct net_device *net)
 485 {
 486         struct device *device = &(net->dev);
 487         device_initialize(device);
 488 }
 489
 490 int netdev_kobject_init(void)
 491 {
 492         return class_register(&net_class);
 493 }