xref: /openbmc/linux/net/core/net-sysfs.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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 #ifdef CONFIG_SYSFS
22 static const char fmt_hex[] = "%#x\n";
23 static const char fmt_long_hex[] = "%#lx\n";
24 static const char fmt_dec[] = "%d\n";
25 static const char fmt_ulong[] = "%lu\n";
26 
27 static inline int dev_isalive(const struct net_device *dev)
28 {
29 	return dev->reg_state <= NETREG_REGISTERED;
30 }
31 
32 /* use same locking rules as GIF* ioctl's */
33 static ssize_t netdev_show(const struct device *dev,
34 			   struct device_attribute *attr, char *buf,
35 			   ssize_t (*format)(const struct net_device *, char *))
36 {
37 	struct net_device *net = to_net_dev(dev);
38 	ssize_t ret = -EINVAL;
39 
40 	read_lock(&dev_base_lock);
41 	if (dev_isalive(net))
42 		ret = (*format)(net, buf);
43 	read_unlock(&dev_base_lock);
44 
45 	return ret;
46 }
47 
48 /* generate a show function for simple field */
49 #define NETDEVICE_SHOW(field, format_string)				\
50 static ssize_t format_##field(const struct net_device *net, char *buf)	\
51 {									\
52 	return sprintf(buf, format_string, net->field);			\
53 }									\
54 static ssize_t show_##field(struct device *dev,				\
55 			    struct device_attribute *attr, char *buf)	\
56 {									\
57 	return netdev_show(dev, attr, buf, format_##field);		\
58 }
59 
60 
61 /* use same locking and permission rules as SIF* ioctl's */
62 static ssize_t netdev_store(struct device *dev, struct device_attribute *attr,
63 			    const char *buf, size_t len,
64 			    int (*set)(struct net_device *, unsigned long))
65 {
66 	struct net_device *net = to_net_dev(dev);
67 	char *endp;
68 	unsigned long new;
69 	int ret = -EINVAL;
70 
71 	if (!capable(CAP_NET_ADMIN))
72 		return -EPERM;
73 
74 	new = simple_strtoul(buf, &endp, 0);
75 	if (endp == buf)
76 		goto err;
77 
78 	rtnl_lock();
79 	if (dev_isalive(net)) {
80 		if ((ret = (*set)(net, new)) == 0)
81 			ret = len;
82 	}
83 	rtnl_unlock();
84  err:
85 	return ret;
86 }
87 
88 NETDEVICE_SHOW(addr_len, fmt_dec);
89 NETDEVICE_SHOW(iflink, fmt_dec);
90 NETDEVICE_SHOW(ifindex, fmt_dec);
91 NETDEVICE_SHOW(features, fmt_long_hex);
92 NETDEVICE_SHOW(type, fmt_dec);
93 NETDEVICE_SHOW(link_mode, 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 device *dev, struct device_attribute *attr,
108 			    char *buf)
109 {
110 	struct net_device *net = to_net_dev(dev);
111 	ssize_t ret = -EINVAL;
112 
113 	read_lock(&dev_base_lock);
114 	if (dev_isalive(net))
115 	    ret = format_addr(buf, net->dev_addr, net->addr_len);
116 	read_unlock(&dev_base_lock);
117 	return ret;
118 }
119 
120 static ssize_t show_broadcast(struct device *dev,
121 			    struct device_attribute *attr, char *buf)
122 {
123 	struct net_device *net = to_net_dev(dev);
124 	if (dev_isalive(net))
125 		return format_addr(buf, net->broadcast, net->addr_len);
126 	return -EINVAL;
127 }
128 
129 static ssize_t show_carrier(struct device *dev,
130 			    struct device_attribute *attr, char *buf)
131 {
132 	struct net_device *netdev = to_net_dev(dev);
133 	if (netif_running(netdev)) {
134 		return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
135 	}
136 	return -EINVAL;
137 }
138 
139 static ssize_t show_dormant(struct device *dev,
140 			    struct device_attribute *attr, char *buf)
141 {
142 	struct net_device *netdev = to_net_dev(dev);
143 
144 	if (netif_running(netdev))
145 		return sprintf(buf, fmt_dec, !!netif_dormant(netdev));
146 
147 	return -EINVAL;
148 }
149 
150 static const char *operstates[] = {
151 	"unknown",
152 	"notpresent", /* currently unused */
153 	"down",
154 	"lowerlayerdown",
155 	"testing", /* currently unused */
156 	"dormant",
157 	"up"
158 };
159 
160 static ssize_t show_operstate(struct device *dev,
161 			      struct device_attribute *attr, char *buf)
162 {
163 	const struct net_device *netdev = to_net_dev(dev);
164 	unsigned char operstate;
165 
166 	read_lock(&dev_base_lock);
167 	operstate = netdev->operstate;
168 	if (!netif_running(netdev))
169 		operstate = IF_OPER_DOWN;
170 	read_unlock(&dev_base_lock);
171 
172 	if (operstate >= ARRAY_SIZE(operstates))
173 		return -EINVAL; /* should not happen */
174 
175 	return sprintf(buf, "%s\n", operstates[operstate]);
176 }
177 
178 /* read-write attributes */
179 NETDEVICE_SHOW(mtu, fmt_dec);
180 
181 static int change_mtu(struct net_device *net, unsigned long new_mtu)
182 {
183 	return dev_set_mtu(net, (int) new_mtu);
184 }
185 
186 static ssize_t store_mtu(struct device *dev, struct device_attribute *attr,
187 			 const char *buf, size_t len)
188 {
189 	return netdev_store(dev, attr, buf, len, change_mtu);
190 }
191 
192 NETDEVICE_SHOW(flags, fmt_hex);
193 
194 static int change_flags(struct net_device *net, unsigned long new_flags)
195 {
196 	return dev_change_flags(net, (unsigned) new_flags);
197 }
198 
199 static ssize_t store_flags(struct device *dev, struct device_attribute *attr,
200 			   const char *buf, size_t len)
201 {
202 	return netdev_store(dev, attr, buf, len, change_flags);
203 }
204 
205 NETDEVICE_SHOW(tx_queue_len, fmt_ulong);
206 
207 static int change_tx_queue_len(struct net_device *net, unsigned long new_len)
208 {
209 	net->tx_queue_len = new_len;
210 	return 0;
211 }
212 
213 static ssize_t store_tx_queue_len(struct device *dev,
214 				  struct device_attribute *attr,
215 				  const char *buf, size_t len)
216 {
217 	return netdev_store(dev, attr, buf, len, change_tx_queue_len);
218 }
219 
220 static struct device_attribute net_class_attributes[] = {
221 	__ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
222 	__ATTR(iflink, S_IRUGO, show_iflink, NULL),
223 	__ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
224 	__ATTR(features, S_IRUGO, show_features, NULL),
225 	__ATTR(type, S_IRUGO, show_type, NULL),
226 	__ATTR(link_mode, S_IRUGO, show_link_mode, NULL),
227 	__ATTR(address, S_IRUGO, show_address, NULL),
228 	__ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
229 	__ATTR(carrier, S_IRUGO, show_carrier, NULL),
230 	__ATTR(dormant, S_IRUGO, show_dormant, NULL),
231 	__ATTR(operstate, S_IRUGO, show_operstate, NULL),
232 	__ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
233 	__ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
234 	__ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
235 	       store_tx_queue_len),
236 	{}
237 };
238 
239 /* Show a given an attribute in the statistics group */
240 static ssize_t netstat_show(const struct device *d,
241 			    struct device_attribute *attr, char *buf,
242 			    unsigned long offset)
243 {
244 	struct net_device *dev = to_net_dev(d);
245 	struct net_device_stats *stats;
246 	ssize_t ret = -EINVAL;
247 
248 	if (offset > sizeof(struct net_device_stats) ||
249 	    offset % sizeof(unsigned long) != 0)
250 		WARN_ON(1);
251 
252 	read_lock(&dev_base_lock);
253 	if (dev_isalive(dev) && dev->get_stats &&
254 	    (stats = (*dev->get_stats)(dev)))
255 		ret = sprintf(buf, fmt_ulong,
256 			      *(unsigned long *)(((u8 *) stats) + offset));
257 
258 	read_unlock(&dev_base_lock);
259 	return ret;
260 }
261 
262 /* generate a read-only statistics attribute */
263 #define NETSTAT_ENTRY(name)						\
264 static ssize_t show_##name(struct device *d,				\
265 			   struct device_attribute *attr, char *buf) 	\
266 {									\
267 	return netstat_show(d, attr, buf,				\
268 			    offsetof(struct net_device_stats, name));	\
269 }									\
270 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
271 
272 NETSTAT_ENTRY(rx_packets);
273 NETSTAT_ENTRY(tx_packets);
274 NETSTAT_ENTRY(rx_bytes);
275 NETSTAT_ENTRY(tx_bytes);
276 NETSTAT_ENTRY(rx_errors);
277 NETSTAT_ENTRY(tx_errors);
278 NETSTAT_ENTRY(rx_dropped);
279 NETSTAT_ENTRY(tx_dropped);
280 NETSTAT_ENTRY(multicast);
281 NETSTAT_ENTRY(collisions);
282 NETSTAT_ENTRY(rx_length_errors);
283 NETSTAT_ENTRY(rx_over_errors);
284 NETSTAT_ENTRY(rx_crc_errors);
285 NETSTAT_ENTRY(rx_frame_errors);
286 NETSTAT_ENTRY(rx_fifo_errors);
287 NETSTAT_ENTRY(rx_missed_errors);
288 NETSTAT_ENTRY(tx_aborted_errors);
289 NETSTAT_ENTRY(tx_carrier_errors);
290 NETSTAT_ENTRY(tx_fifo_errors);
291 NETSTAT_ENTRY(tx_heartbeat_errors);
292 NETSTAT_ENTRY(tx_window_errors);
293 NETSTAT_ENTRY(rx_compressed);
294 NETSTAT_ENTRY(tx_compressed);
295 
296 static struct attribute *netstat_attrs[] = {
297 	&dev_attr_rx_packets.attr,
298 	&dev_attr_tx_packets.attr,
299 	&dev_attr_rx_bytes.attr,
300 	&dev_attr_tx_bytes.attr,
301 	&dev_attr_rx_errors.attr,
302 	&dev_attr_tx_errors.attr,
303 	&dev_attr_rx_dropped.attr,
304 	&dev_attr_tx_dropped.attr,
305 	&dev_attr_multicast.attr,
306 	&dev_attr_collisions.attr,
307 	&dev_attr_rx_length_errors.attr,
308 	&dev_attr_rx_over_errors.attr,
309 	&dev_attr_rx_crc_errors.attr,
310 	&dev_attr_rx_frame_errors.attr,
311 	&dev_attr_rx_fifo_errors.attr,
312 	&dev_attr_rx_missed_errors.attr,
313 	&dev_attr_tx_aborted_errors.attr,
314 	&dev_attr_tx_carrier_errors.attr,
315 	&dev_attr_tx_fifo_errors.attr,
316 	&dev_attr_tx_heartbeat_errors.attr,
317 	&dev_attr_tx_window_errors.attr,
318 	&dev_attr_rx_compressed.attr,
319 	&dev_attr_tx_compressed.attr,
320 	NULL
321 };
322 
323 
324 static struct attribute_group netstat_group = {
325 	.name  = "statistics",
326 	.attrs  = netstat_attrs,
327 };
328 
329 #ifdef CONFIG_WIRELESS_EXT
330 /* helper function that does all the locking etc for wireless stats */
331 static ssize_t wireless_show(struct device *d, char *buf,
332 			     ssize_t (*format)(const struct iw_statistics *,
333 					       char *))
334 {
335 	struct net_device *dev = to_net_dev(d);
336 	const struct iw_statistics *iw = NULL;
337 	ssize_t ret = -EINVAL;
338 
339 	read_lock(&dev_base_lock);
340 	if (dev_isalive(dev)) {
341 		if (dev->wireless_handlers &&
342 		    dev->wireless_handlers->get_wireless_stats)
343 			iw = dev->wireless_handlers->get_wireless_stats(dev);
344 		if (iw != NULL)
345 			ret = (*format)(iw, buf);
346 	}
347 	read_unlock(&dev_base_lock);
348 
349 	return ret;
350 }
351 
352 /* show function template for wireless fields */
353 #define WIRELESS_SHOW(name, field, format_string)			\
354 static ssize_t format_iw_##name(const struct iw_statistics *iw, char *buf) \
355 {									\
356 	return sprintf(buf, format_string, iw->field);			\
357 }									\
358 static ssize_t show_iw_##name(struct device *d,				\
359 			      struct device_attribute *attr, char *buf)	\
360 {									\
361 	return wireless_show(d, buf, format_iw_##name);			\
362 }									\
363 static DEVICE_ATTR(name, S_IRUGO, show_iw_##name, NULL)
364 
365 WIRELESS_SHOW(status, status, fmt_hex);
366 WIRELESS_SHOW(link, qual.qual, fmt_dec);
367 WIRELESS_SHOW(level, qual.level, fmt_dec);
368 WIRELESS_SHOW(noise, qual.noise, fmt_dec);
369 WIRELESS_SHOW(nwid, discard.nwid, fmt_dec);
370 WIRELESS_SHOW(crypt, discard.code, fmt_dec);
371 WIRELESS_SHOW(fragment, discard.fragment, fmt_dec);
372 WIRELESS_SHOW(misc, discard.misc, fmt_dec);
373 WIRELESS_SHOW(retries, discard.retries, fmt_dec);
374 WIRELESS_SHOW(beacon, miss.beacon, fmt_dec);
375 
376 static struct attribute *wireless_attrs[] = {
377 	&dev_attr_status.attr,
378 	&dev_attr_link.attr,
379 	&dev_attr_level.attr,
380 	&dev_attr_noise.attr,
381 	&dev_attr_nwid.attr,
382 	&dev_attr_crypt.attr,
383 	&dev_attr_fragment.attr,
384 	&dev_attr_retries.attr,
385 	&dev_attr_misc.attr,
386 	&dev_attr_beacon.attr,
387 	NULL
388 };
389 
390 static struct attribute_group wireless_group = {
391 	.name = "wireless",
392 	.attrs = wireless_attrs,
393 };
394 #endif
395 
396 #endif /* CONFIG_SYSFS */
397 
398 #ifdef CONFIG_HOTPLUG
399 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
400 {
401 	struct net_device *dev = to_net_dev(d);
402 	int retval;
403 
404 	/* pass interface to uevent. */
405 	retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
406 	if (retval)
407 		goto exit;
408 
409 	/* pass ifindex to uevent.
410 	 * ifindex is useful as it won't change (interface name may change)
411 	 * and is what RtNetlink uses natively. */
412 	retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
413 
414 exit:
415 	return retval;
416 }
417 #endif
418 
419 /*
420  *	netdev_release -- destroy and free a dead device.
421  *	Called when last reference to device kobject is gone.
422  */
423 static void netdev_release(struct device *d)
424 {
425 	struct net_device *dev = to_net_dev(d);
426 
427 	BUG_ON(dev->reg_state != NETREG_RELEASED);
428 
429 	kfree((char *)dev - dev->padded);
430 }
431 
432 static struct class net_class = {
433 	.name = "net",
434 	.dev_release = netdev_release,
435 #ifdef CONFIG_SYSFS
436 	.dev_attrs = net_class_attributes,
437 #endif /* CONFIG_SYSFS */
438 #ifdef CONFIG_HOTPLUG
439 	.dev_uevent = netdev_uevent,
440 #endif
441 };
442 
443 /* Delete sysfs entries but hold kobject reference until after all
444  * netdev references are gone.
445  */
446 void netdev_unregister_kobject(struct net_device * net)
447 {
448 	struct device *dev = &(net->dev);
449 
450 	kobject_get(&dev->kobj);
451 	device_del(dev);
452 }
453 
454 /* Create sysfs entries for network device. */
455 int netdev_register_kobject(struct net_device *net)
456 {
457 	struct device *dev = &(net->dev);
458 	struct attribute_group **groups = net->sysfs_groups;
459 
460 	device_initialize(dev);
461 	dev->class = &net_class;
462 	dev->platform_data = net;
463 	dev->groups = groups;
464 
465 	BUILD_BUG_ON(BUS_ID_SIZE < IFNAMSIZ);
466 	strlcpy(dev->bus_id, net->name, BUS_ID_SIZE);
467 
468 #ifdef CONFIG_SYSFS
469 	if (net->get_stats)
470 		*groups++ = &netstat_group;
471 
472 #ifdef CONFIG_WIRELESS_EXT
473 	if (net->wireless_handlers && net->wireless_handlers->get_wireless_stats)
474 		*groups++ = &wireless_group;
475 #endif
476 #endif /* CONFIG_SYSFS */
477 
478 	return device_add(dev);
479 }
480 
481 int netdev_kobject_init(void)
482 {
483 	return class_register(&net_class);
484 }
485