xref: /openbmc/linux/net/core/net-sysfs.c (revision 545e4006)
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_SYSFS
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_SYSFS
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 }
494