[NET]: Take dev_base_lock when moving device name hash list entry
[linux-2.6] / 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 }