xref: /linux/net/core/net-sysfs.c (revision d8327c784b51b57dac2c26cfad87dce0d68dfd98)
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/config.h>
14 #include <linux/kernel.h>
15 #include <linux/netdevice.h>
16 #include <linux/if_arp.h>
17 #include <net/sock.h>
18 #include <linux/rtnetlink.h>
19 #include <linux/wireless.h>
20 #include <net/iw_handler.h>
21 
22 #define to_class_dev(obj) container_of(obj,struct class_device,kobj)
23 #define to_net_dev(class) container_of(class, struct net_device, class_dev)
24 
25 static const char fmt_hex[] = "%#x\n";
26 static const char fmt_long_hex[] = "%#lx\n";
27 static const char fmt_dec[] = "%d\n";
28 static const char fmt_ulong[] = "%lu\n";
29 
30 static inline int dev_isalive(const struct net_device *dev)
31 {
32 	return dev->reg_state == NETREG_REGISTERED;
33 }
34 
35 /* use same locking rules as GIF* ioctl's */
36 static ssize_t netdev_show(const struct class_device *cd, char *buf,
37 			   ssize_t (*format)(const struct net_device *, char *))
38 {
39 	struct net_device *net = to_net_dev(cd);
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 class_device *cd, char *buf)		\
57 {									\
58 	return netdev_show(cd, buf, format_##field);			\
59 }
60 
61 
62 /* use same locking and permission rules as SIF* ioctl's */
63 static ssize_t netdev_store(struct class_device *dev,
64 			    const char *buf, size_t len,
65 			    int (*set)(struct net_device *, unsigned long))
66 {
67 	struct net_device *net = to_net_dev(dev);
68 	char *endp;
69 	unsigned long new;
70 	int ret = -EINVAL;
71 
72 	if (!capable(CAP_NET_ADMIN))
73 		return -EPERM;
74 
75 	new = simple_strtoul(buf, &endp, 0);
76 	if (endp == buf)
77 		goto err;
78 
79 	rtnl_lock();
80 	if (dev_isalive(net)) {
81 		if ((ret = (*set)(net, new)) == 0)
82 			ret = len;
83 	}
84 	rtnl_unlock();
85  err:
86 	return ret;
87 }
88 
89 NETDEVICE_SHOW(addr_len, fmt_dec);
90 NETDEVICE_SHOW(iflink, fmt_dec);
91 NETDEVICE_SHOW(ifindex, fmt_dec);
92 NETDEVICE_SHOW(features, fmt_long_hex);
93 NETDEVICE_SHOW(type, fmt_dec);
94 
95 /* use same locking rules as GIFHWADDR ioctl's */
96 static ssize_t format_addr(char *buf, const unsigned char *addr, int len)
97 {
98 	int i;
99 	char *cp = buf;
100 
101 	for (i = 0; i < len; i++)
102 		cp += sprintf(cp, "%02x%c", addr[i],
103 			      i == (len - 1) ? '\n' : ':');
104 	return cp - buf;
105 }
106 
107 static ssize_t show_address(struct class_device *dev, 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 class_device *dev, char *buf)
120 {
121 	struct net_device *net = to_net_dev(dev);
122 	if (dev_isalive(net))
123 		return format_addr(buf, net->broadcast, net->addr_len);
124 	return -EINVAL;
125 }
126 
127 static ssize_t show_carrier(struct class_device *dev, char *buf)
128 {
129 	struct net_device *netdev = to_net_dev(dev);
130 	if (netif_running(netdev)) {
131 		return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
132 	}
133 	return -EINVAL;
134 }
135 
136 /* read-write attributes */
137 NETDEVICE_SHOW(mtu, fmt_dec);
138 
139 static int change_mtu(struct net_device *net, unsigned long new_mtu)
140 {
141 	return dev_set_mtu(net, (int) new_mtu);
142 }
143 
144 static ssize_t store_mtu(struct class_device *dev, const char *buf, size_t len)
145 {
146 	return netdev_store(dev, buf, len, change_mtu);
147 }
148 
149 NETDEVICE_SHOW(flags, fmt_hex);
150 
151 static int change_flags(struct net_device *net, unsigned long new_flags)
152 {
153 	return dev_change_flags(net, (unsigned) new_flags);
154 }
155 
156 static ssize_t store_flags(struct class_device *dev, const char *buf, size_t len)
157 {
158 	return netdev_store(dev, buf, len, change_flags);
159 }
160 
161 NETDEVICE_SHOW(tx_queue_len, fmt_ulong);
162 
163 static int change_tx_queue_len(struct net_device *net, unsigned long new_len)
164 {
165 	net->tx_queue_len = new_len;
166 	return 0;
167 }
168 
169 static ssize_t store_tx_queue_len(struct class_device *dev, const char *buf, size_t len)
170 {
171 	return netdev_store(dev, buf, len, change_tx_queue_len);
172 }
173 
174 NETDEVICE_SHOW(weight, fmt_dec);
175 
176 static int change_weight(struct net_device *net, unsigned long new_weight)
177 {
178 	net->weight = new_weight;
179 	return 0;
180 }
181 
182 static ssize_t store_weight(struct class_device *dev, const char *buf, size_t len)
183 {
184 	return netdev_store(dev, buf, len, change_weight);
185 }
186 
187 static struct class_device_attribute net_class_attributes[] = {
188 	__ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
189 	__ATTR(iflink, S_IRUGO, show_iflink, NULL),
190 	__ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
191 	__ATTR(features, S_IRUGO, show_features, NULL),
192 	__ATTR(type, S_IRUGO, show_type, NULL),
193 	__ATTR(address, S_IRUGO, show_address, NULL),
194 	__ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
195 	__ATTR(carrier, S_IRUGO, show_carrier, NULL),
196 	__ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
197 	__ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
198 	__ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
199 	       store_tx_queue_len),
200 	__ATTR(weight, S_IRUGO | S_IWUSR, show_weight, store_weight),
201 	{}
202 };
203 
204 /* Show a given an attribute in the statistics group */
205 static ssize_t netstat_show(const struct class_device *cd, char *buf,
206 			    unsigned long offset)
207 {
208 	struct net_device *dev = to_net_dev(cd);
209 	struct net_device_stats *stats;
210 	ssize_t ret = -EINVAL;
211 
212 	if (offset > sizeof(struct net_device_stats) ||
213 	    offset % sizeof(unsigned long) != 0)
214 		WARN_ON(1);
215 
216 	read_lock(&dev_base_lock);
217 	if (dev_isalive(dev) && dev->get_stats &&
218 	    (stats = (*dev->get_stats)(dev)))
219 		ret = sprintf(buf, fmt_ulong,
220 			      *(unsigned long *)(((u8 *) stats) + offset));
221 
222 	read_unlock(&dev_base_lock);
223 	return ret;
224 }
225 
226 /* generate a read-only statistics attribute */
227 #define NETSTAT_ENTRY(name)						\
228 static ssize_t show_##name(struct class_device *cd, char *buf) 		\
229 {									\
230 	return netstat_show(cd, buf, 					\
231 			    offsetof(struct net_device_stats, name));	\
232 }									\
233 static CLASS_DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
234 
235 NETSTAT_ENTRY(rx_packets);
236 NETSTAT_ENTRY(tx_packets);
237 NETSTAT_ENTRY(rx_bytes);
238 NETSTAT_ENTRY(tx_bytes);
239 NETSTAT_ENTRY(rx_errors);
240 NETSTAT_ENTRY(tx_errors);
241 NETSTAT_ENTRY(rx_dropped);
242 NETSTAT_ENTRY(tx_dropped);
243 NETSTAT_ENTRY(multicast);
244 NETSTAT_ENTRY(collisions);
245 NETSTAT_ENTRY(rx_length_errors);
246 NETSTAT_ENTRY(rx_over_errors);
247 NETSTAT_ENTRY(rx_crc_errors);
248 NETSTAT_ENTRY(rx_frame_errors);
249 NETSTAT_ENTRY(rx_fifo_errors);
250 NETSTAT_ENTRY(rx_missed_errors);
251 NETSTAT_ENTRY(tx_aborted_errors);
252 NETSTAT_ENTRY(tx_carrier_errors);
253 NETSTAT_ENTRY(tx_fifo_errors);
254 NETSTAT_ENTRY(tx_heartbeat_errors);
255 NETSTAT_ENTRY(tx_window_errors);
256 NETSTAT_ENTRY(rx_compressed);
257 NETSTAT_ENTRY(tx_compressed);
258 
259 static struct attribute *netstat_attrs[] = {
260 	&class_device_attr_rx_packets.attr,
261 	&class_device_attr_tx_packets.attr,
262 	&class_device_attr_rx_bytes.attr,
263 	&class_device_attr_tx_bytes.attr,
264 	&class_device_attr_rx_errors.attr,
265 	&class_device_attr_tx_errors.attr,
266 	&class_device_attr_rx_dropped.attr,
267 	&class_device_attr_tx_dropped.attr,
268 	&class_device_attr_multicast.attr,
269 	&class_device_attr_collisions.attr,
270 	&class_device_attr_rx_length_errors.attr,
271 	&class_device_attr_rx_over_errors.attr,
272 	&class_device_attr_rx_crc_errors.attr,
273 	&class_device_attr_rx_frame_errors.attr,
274 	&class_device_attr_rx_fifo_errors.attr,
275 	&class_device_attr_rx_missed_errors.attr,
276 	&class_device_attr_tx_aborted_errors.attr,
277 	&class_device_attr_tx_carrier_errors.attr,
278 	&class_device_attr_tx_fifo_errors.attr,
279 	&class_device_attr_tx_heartbeat_errors.attr,
280 	&class_device_attr_tx_window_errors.attr,
281 	&class_device_attr_rx_compressed.attr,
282 	&class_device_attr_tx_compressed.attr,
283 	NULL
284 };
285 
286 
287 static struct attribute_group netstat_group = {
288 	.name  = "statistics",
289 	.attrs  = netstat_attrs,
290 };
291 
292 #ifdef WIRELESS_EXT
293 /* helper function that does all the locking etc for wireless stats */
294 static ssize_t wireless_show(struct class_device *cd, char *buf,
295 			     ssize_t (*format)(const struct iw_statistics *,
296 					       char *))
297 {
298 	struct net_device *dev = to_net_dev(cd);
299 	const struct iw_statistics *iw = NULL;
300 	ssize_t ret = -EINVAL;
301 
302 	read_lock(&dev_base_lock);
303 	if (dev_isalive(dev)) {
304 		if(dev->wireless_handlers &&
305 		   dev->wireless_handlers->get_wireless_stats)
306 			iw = dev->wireless_handlers->get_wireless_stats(dev);
307 		else if (dev->get_wireless_stats)
308 			iw = dev->get_wireless_stats(dev);
309 		if (iw != NULL)
310 			ret = (*format)(iw, buf);
311 	}
312 	read_unlock(&dev_base_lock);
313 
314 	return ret;
315 }
316 
317 /* show function template for wireless fields */
318 #define WIRELESS_SHOW(name, field, format_string)			\
319 static ssize_t format_iw_##name(const struct iw_statistics *iw, char *buf) \
320 {									\
321 	return sprintf(buf, format_string, iw->field);			\
322 }									\
323 static ssize_t show_iw_##name(struct class_device *cd, char *buf)	\
324 {									\
325 	return wireless_show(cd, buf, format_iw_##name);		\
326 }									\
327 static CLASS_DEVICE_ATTR(name, S_IRUGO, show_iw_##name, NULL)
328 
329 WIRELESS_SHOW(status, status, fmt_hex);
330 WIRELESS_SHOW(link, qual.qual, fmt_dec);
331 WIRELESS_SHOW(level, qual.level, fmt_dec);
332 WIRELESS_SHOW(noise, qual.noise, fmt_dec);
333 WIRELESS_SHOW(nwid, discard.nwid, fmt_dec);
334 WIRELESS_SHOW(crypt, discard.code, fmt_dec);
335 WIRELESS_SHOW(fragment, discard.fragment, fmt_dec);
336 WIRELESS_SHOW(misc, discard.misc, fmt_dec);
337 WIRELESS_SHOW(retries, discard.retries, fmt_dec);
338 WIRELESS_SHOW(beacon, miss.beacon, fmt_dec);
339 
340 static struct attribute *wireless_attrs[] = {
341 	&class_device_attr_status.attr,
342 	&class_device_attr_link.attr,
343 	&class_device_attr_level.attr,
344 	&class_device_attr_noise.attr,
345 	&class_device_attr_nwid.attr,
346 	&class_device_attr_crypt.attr,
347 	&class_device_attr_fragment.attr,
348 	&class_device_attr_retries.attr,
349 	&class_device_attr_misc.attr,
350 	&class_device_attr_beacon.attr,
351 	NULL
352 };
353 
354 static struct attribute_group wireless_group = {
355 	.name = "wireless",
356 	.attrs = wireless_attrs,
357 };
358 #endif
359 
360 #ifdef CONFIG_HOTPLUG
361 static int netdev_uevent(struct class_device *cd, char **envp,
362 			 int num_envp, char *buf, int size)
363 {
364 	struct net_device *dev = to_net_dev(cd);
365 	int i = 0;
366 	int n;
367 
368 	/* pass interface to uevent. */
369 	envp[i++] = buf;
370 	n = snprintf(buf, size, "INTERFACE=%s", dev->name) + 1;
371 	buf += n;
372 	size -= n;
373 
374 	if ((size <= 0) || (i >= num_envp))
375 		return -ENOMEM;
376 
377 	envp[i] = NULL;
378 	return 0;
379 }
380 #endif
381 
382 /*
383  *	netdev_release -- destroy and free a dead device.
384  *	Called when last reference to class_device kobject is gone.
385  */
386 static void netdev_release(struct class_device *cd)
387 {
388 	struct net_device *dev
389 		= container_of(cd, struct net_device, class_dev);
390 
391 	BUG_ON(dev->reg_state != NETREG_RELEASED);
392 
393 	kfree((char *)dev - dev->padded);
394 }
395 
396 static struct class net_class = {
397 	.name = "net",
398 	.release = netdev_release,
399 	.class_dev_attrs = net_class_attributes,
400 #ifdef CONFIG_HOTPLUG
401 	.uevent = netdev_uevent,
402 #endif
403 };
404 
405 void netdev_unregister_sysfs(struct net_device * net)
406 {
407 	struct class_device * class_dev = &(net->class_dev);
408 
409 	if (net->get_stats)
410 		sysfs_remove_group(&class_dev->kobj, &netstat_group);
411 
412 #ifdef WIRELESS_EXT
413 	if (net->get_wireless_stats || (net->wireless_handlers &&
414 			net->wireless_handlers->get_wireless_stats))
415 		sysfs_remove_group(&class_dev->kobj, &wireless_group);
416 #endif
417 	class_device_del(class_dev);
418 
419 }
420 
421 /* Create sysfs entries for network device. */
422 int netdev_register_sysfs(struct net_device *net)
423 {
424 	struct class_device *class_dev = &(net->class_dev);
425 	int ret;
426 
427 	class_dev->class = &net_class;
428 	class_dev->class_data = net;
429 
430 	strlcpy(class_dev->class_id, net->name, BUS_ID_SIZE);
431 	if ((ret = class_device_register(class_dev)))
432 		goto out;
433 
434 	if (net->get_stats &&
435 	    (ret = sysfs_create_group(&class_dev->kobj, &netstat_group)))
436 		goto out_unreg;
437 
438 #ifdef WIRELESS_EXT
439 	if (net->get_wireless_stats || (net->wireless_handlers &&
440 			net->wireless_handlers->get_wireless_stats)) {
441 		ret = sysfs_create_group(&class_dev->kobj, &wireless_group);
442 		if (ret)
443 			goto out_cleanup;
444 	}
445 	return 0;
446 out_cleanup:
447 	if (net->get_stats)
448 		sysfs_remove_group(&class_dev->kobj, &netstat_group);
449 #else
450 	return 0;
451 #endif
452 
453 out_unreg:
454 	printk(KERN_WARNING "%s: sysfs attribute registration failed %d\n",
455 	       net->name, ret);
456 	class_device_unregister(class_dev);
457 out:
458 	return ret;
459 }
460 
461 int netdev_sysfs_init(void)
462 {
463 	return class_register(&net_class);
464 }
465