xref: /openbmc/linux/net/core/net-sysfs.c (revision a1e58bbd)
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 }
475