xref: /openbmc/linux/net/core/net-sysfs.c (revision a09d2831)
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/wext.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 	if (!rtnl_trylock())
81 		return restart_syscall();
82 
83 	if (dev_isalive(net)) {
84 		if ((ret = (*set)(net, new)) == 0)
85 			ret = len;
86 	}
87 	rtnl_unlock();
88  err:
89 	return ret;
90 }
91 
92 NETDEVICE_SHOW(dev_id, fmt_hex);
93 NETDEVICE_SHOW(addr_len, fmt_dec);
94 NETDEVICE_SHOW(iflink, fmt_dec);
95 NETDEVICE_SHOW(ifindex, fmt_dec);
96 NETDEVICE_SHOW(features, fmt_long_hex);
97 NETDEVICE_SHOW(type, fmt_dec);
98 NETDEVICE_SHOW(link_mode, fmt_dec);
99 
100 /* use same locking rules as GIFHWADDR ioctl's */
101 static ssize_t show_address(struct device *dev, struct device_attribute *attr,
102 			    char *buf)
103 {
104 	struct net_device *net = to_net_dev(dev);
105 	ssize_t ret = -EINVAL;
106 
107 	read_lock(&dev_base_lock);
108 	if (dev_isalive(net))
109 		ret = sysfs_format_mac(buf, net->dev_addr, net->addr_len);
110 	read_unlock(&dev_base_lock);
111 	return ret;
112 }
113 
114 static ssize_t show_broadcast(struct device *dev,
115 			    struct device_attribute *attr, char *buf)
116 {
117 	struct net_device *net = to_net_dev(dev);
118 	if (dev_isalive(net))
119 		return sysfs_format_mac(buf, net->broadcast, net->addr_len);
120 	return -EINVAL;
121 }
122 
123 static ssize_t show_carrier(struct device *dev,
124 			    struct device_attribute *attr, char *buf)
125 {
126 	struct net_device *netdev = to_net_dev(dev);
127 	if (netif_running(netdev)) {
128 		return sprintf(buf, fmt_dec, !!netif_carrier_ok(netdev));
129 	}
130 	return -EINVAL;
131 }
132 
133 static ssize_t show_speed(struct device *dev,
134 			  struct device_attribute *attr, char *buf)
135 {
136 	struct net_device *netdev = to_net_dev(dev);
137 	int ret = -EINVAL;
138 
139 	if (!rtnl_trylock())
140 		return restart_syscall();
141 
142 	if (netif_running(netdev) &&
143 	    netdev->ethtool_ops &&
144 	    netdev->ethtool_ops->get_settings) {
145 		struct ethtool_cmd cmd = { ETHTOOL_GSET };
146 
147 		if (!netdev->ethtool_ops->get_settings(netdev, &cmd))
148 			ret = sprintf(buf, fmt_dec, ethtool_cmd_speed(&cmd));
149 	}
150 	rtnl_unlock();
151 	return ret;
152 }
153 
154 static ssize_t show_duplex(struct device *dev,
155 			   struct device_attribute *attr, char *buf)
156 {
157 	struct net_device *netdev = to_net_dev(dev);
158 	int ret = -EINVAL;
159 
160 	if (!rtnl_trylock())
161 		return restart_syscall();
162 
163 	if (netif_running(netdev) &&
164 	    netdev->ethtool_ops &&
165 	    netdev->ethtool_ops->get_settings) {
166 		struct ethtool_cmd cmd = { ETHTOOL_GSET };
167 
168 		if (!netdev->ethtool_ops->get_settings(netdev, &cmd))
169 			ret = sprintf(buf, "%s\n", cmd.duplex ? "full" : "half");
170 	}
171 	rtnl_unlock();
172 	return ret;
173 }
174 
175 static ssize_t show_dormant(struct device *dev,
176 			    struct device_attribute *attr, char *buf)
177 {
178 	struct net_device *netdev = to_net_dev(dev);
179 
180 	if (netif_running(netdev))
181 		return sprintf(buf, fmt_dec, !!netif_dormant(netdev));
182 
183 	return -EINVAL;
184 }
185 
186 static const char *const operstates[] = {
187 	"unknown",
188 	"notpresent", /* currently unused */
189 	"down",
190 	"lowerlayerdown",
191 	"testing", /* currently unused */
192 	"dormant",
193 	"up"
194 };
195 
196 static ssize_t show_operstate(struct device *dev,
197 			      struct device_attribute *attr, char *buf)
198 {
199 	const struct net_device *netdev = to_net_dev(dev);
200 	unsigned char operstate;
201 
202 	read_lock(&dev_base_lock);
203 	operstate = netdev->operstate;
204 	if (!netif_running(netdev))
205 		operstate = IF_OPER_DOWN;
206 	read_unlock(&dev_base_lock);
207 
208 	if (operstate >= ARRAY_SIZE(operstates))
209 		return -EINVAL; /* should not happen */
210 
211 	return sprintf(buf, "%s\n", operstates[operstate]);
212 }
213 
214 /* read-write attributes */
215 NETDEVICE_SHOW(mtu, fmt_dec);
216 
217 static int change_mtu(struct net_device *net, unsigned long new_mtu)
218 {
219 	return dev_set_mtu(net, (int) new_mtu);
220 }
221 
222 static ssize_t store_mtu(struct device *dev, struct device_attribute *attr,
223 			 const char *buf, size_t len)
224 {
225 	return netdev_store(dev, attr, buf, len, change_mtu);
226 }
227 
228 NETDEVICE_SHOW(flags, fmt_hex);
229 
230 static int change_flags(struct net_device *net, unsigned long new_flags)
231 {
232 	return dev_change_flags(net, (unsigned) new_flags);
233 }
234 
235 static ssize_t store_flags(struct device *dev, struct device_attribute *attr,
236 			   const char *buf, size_t len)
237 {
238 	return netdev_store(dev, attr, buf, len, change_flags);
239 }
240 
241 NETDEVICE_SHOW(tx_queue_len, fmt_ulong);
242 
243 static int change_tx_queue_len(struct net_device *net, unsigned long new_len)
244 {
245 	net->tx_queue_len = new_len;
246 	return 0;
247 }
248 
249 static ssize_t store_tx_queue_len(struct device *dev,
250 				  struct device_attribute *attr,
251 				  const char *buf, size_t len)
252 {
253 	return netdev_store(dev, attr, buf, len, change_tx_queue_len);
254 }
255 
256 static ssize_t store_ifalias(struct device *dev, struct device_attribute *attr,
257 			     const char *buf, size_t len)
258 {
259 	struct net_device *netdev = to_net_dev(dev);
260 	size_t count = len;
261 	ssize_t ret;
262 
263 	if (!capable(CAP_NET_ADMIN))
264 		return -EPERM;
265 
266 	/* ignore trailing newline */
267 	if (len >  0 && buf[len - 1] == '\n')
268 		--count;
269 
270 	if (!rtnl_trylock())
271 		return restart_syscall();
272 	ret = dev_set_alias(netdev, buf, count);
273 	rtnl_unlock();
274 
275 	return ret < 0 ? ret : len;
276 }
277 
278 static ssize_t show_ifalias(struct device *dev,
279 			    struct device_attribute *attr, char *buf)
280 {
281 	const struct net_device *netdev = to_net_dev(dev);
282 	ssize_t ret = 0;
283 
284 	if (!rtnl_trylock())
285 		return restart_syscall();
286 	if (netdev->ifalias)
287 		ret = sprintf(buf, "%s\n", netdev->ifalias);
288 	rtnl_unlock();
289 	return ret;
290 }
291 
292 static struct device_attribute net_class_attributes[] = {
293 	__ATTR(addr_len, S_IRUGO, show_addr_len, NULL),
294 	__ATTR(dev_id, S_IRUGO, show_dev_id, NULL),
295 	__ATTR(ifalias, S_IRUGO | S_IWUSR, show_ifalias, store_ifalias),
296 	__ATTR(iflink, S_IRUGO, show_iflink, NULL),
297 	__ATTR(ifindex, S_IRUGO, show_ifindex, NULL),
298 	__ATTR(features, S_IRUGO, show_features, NULL),
299 	__ATTR(type, S_IRUGO, show_type, NULL),
300 	__ATTR(link_mode, S_IRUGO, show_link_mode, NULL),
301 	__ATTR(address, S_IRUGO, show_address, NULL),
302 	__ATTR(broadcast, S_IRUGO, show_broadcast, NULL),
303 	__ATTR(carrier, S_IRUGO, show_carrier, NULL),
304 	__ATTR(speed, S_IRUGO, show_speed, NULL),
305 	__ATTR(duplex, S_IRUGO, show_duplex, NULL),
306 	__ATTR(dormant, S_IRUGO, show_dormant, NULL),
307 	__ATTR(operstate, S_IRUGO, show_operstate, NULL),
308 	__ATTR(mtu, S_IRUGO | S_IWUSR, show_mtu, store_mtu),
309 	__ATTR(flags, S_IRUGO | S_IWUSR, show_flags, store_flags),
310 	__ATTR(tx_queue_len, S_IRUGO | S_IWUSR, show_tx_queue_len,
311 	       store_tx_queue_len),
312 	{}
313 };
314 
315 /* Show a given an attribute in the statistics group */
316 static ssize_t netstat_show(const struct device *d,
317 			    struct device_attribute *attr, char *buf,
318 			    unsigned long offset)
319 {
320 	struct net_device *dev = to_net_dev(d);
321 	ssize_t ret = -EINVAL;
322 
323 	WARN_ON(offset > sizeof(struct net_device_stats) ||
324 			offset % sizeof(unsigned long) != 0);
325 
326 	read_lock(&dev_base_lock);
327 	if (dev_isalive(dev)) {
328 		const struct net_device_stats *stats = dev_get_stats(dev);
329 		ret = sprintf(buf, fmt_ulong,
330 			      *(unsigned long *)(((u8 *) stats) + offset));
331 	}
332 	read_unlock(&dev_base_lock);
333 	return ret;
334 }
335 
336 /* generate a read-only statistics attribute */
337 #define NETSTAT_ENTRY(name)						\
338 static ssize_t show_##name(struct device *d,				\
339 			   struct device_attribute *attr, char *buf) 	\
340 {									\
341 	return netstat_show(d, attr, buf,				\
342 			    offsetof(struct net_device_stats, name));	\
343 }									\
344 static DEVICE_ATTR(name, S_IRUGO, show_##name, NULL)
345 
346 NETSTAT_ENTRY(rx_packets);
347 NETSTAT_ENTRY(tx_packets);
348 NETSTAT_ENTRY(rx_bytes);
349 NETSTAT_ENTRY(tx_bytes);
350 NETSTAT_ENTRY(rx_errors);
351 NETSTAT_ENTRY(tx_errors);
352 NETSTAT_ENTRY(rx_dropped);
353 NETSTAT_ENTRY(tx_dropped);
354 NETSTAT_ENTRY(multicast);
355 NETSTAT_ENTRY(collisions);
356 NETSTAT_ENTRY(rx_length_errors);
357 NETSTAT_ENTRY(rx_over_errors);
358 NETSTAT_ENTRY(rx_crc_errors);
359 NETSTAT_ENTRY(rx_frame_errors);
360 NETSTAT_ENTRY(rx_fifo_errors);
361 NETSTAT_ENTRY(rx_missed_errors);
362 NETSTAT_ENTRY(tx_aborted_errors);
363 NETSTAT_ENTRY(tx_carrier_errors);
364 NETSTAT_ENTRY(tx_fifo_errors);
365 NETSTAT_ENTRY(tx_heartbeat_errors);
366 NETSTAT_ENTRY(tx_window_errors);
367 NETSTAT_ENTRY(rx_compressed);
368 NETSTAT_ENTRY(tx_compressed);
369 
370 static struct attribute *netstat_attrs[] = {
371 	&dev_attr_rx_packets.attr,
372 	&dev_attr_tx_packets.attr,
373 	&dev_attr_rx_bytes.attr,
374 	&dev_attr_tx_bytes.attr,
375 	&dev_attr_rx_errors.attr,
376 	&dev_attr_tx_errors.attr,
377 	&dev_attr_rx_dropped.attr,
378 	&dev_attr_tx_dropped.attr,
379 	&dev_attr_multicast.attr,
380 	&dev_attr_collisions.attr,
381 	&dev_attr_rx_length_errors.attr,
382 	&dev_attr_rx_over_errors.attr,
383 	&dev_attr_rx_crc_errors.attr,
384 	&dev_attr_rx_frame_errors.attr,
385 	&dev_attr_rx_fifo_errors.attr,
386 	&dev_attr_rx_missed_errors.attr,
387 	&dev_attr_tx_aborted_errors.attr,
388 	&dev_attr_tx_carrier_errors.attr,
389 	&dev_attr_tx_fifo_errors.attr,
390 	&dev_attr_tx_heartbeat_errors.attr,
391 	&dev_attr_tx_window_errors.attr,
392 	&dev_attr_rx_compressed.attr,
393 	&dev_attr_tx_compressed.attr,
394 	NULL
395 };
396 
397 
398 static struct attribute_group netstat_group = {
399 	.name  = "statistics",
400 	.attrs  = netstat_attrs,
401 };
402 
403 #ifdef CONFIG_WIRELESS_EXT_SYSFS
404 /* helper function that does all the locking etc for wireless stats */
405 static ssize_t wireless_show(struct device *d, char *buf,
406 			     ssize_t (*format)(const struct iw_statistics *,
407 					       char *))
408 {
409 	struct net_device *dev = to_net_dev(d);
410 	const struct iw_statistics *iw;
411 	ssize_t ret = -EINVAL;
412 
413 	rtnl_lock();
414 	if (dev_isalive(dev)) {
415 		iw = get_wireless_stats(dev);
416 		if (iw)
417 			ret = (*format)(iw, buf);
418 	}
419 	rtnl_unlock();
420 
421 	return ret;
422 }
423 
424 /* show function template for wireless fields */
425 #define WIRELESS_SHOW(name, field, format_string)			\
426 static ssize_t format_iw_##name(const struct iw_statistics *iw, char *buf) \
427 {									\
428 	return sprintf(buf, format_string, iw->field);			\
429 }									\
430 static ssize_t show_iw_##name(struct device *d,				\
431 			      struct device_attribute *attr, char *buf)	\
432 {									\
433 	return wireless_show(d, buf, format_iw_##name);			\
434 }									\
435 static DEVICE_ATTR(name, S_IRUGO, show_iw_##name, NULL)
436 
437 WIRELESS_SHOW(status, status, fmt_hex);
438 WIRELESS_SHOW(link, qual.qual, fmt_dec);
439 WIRELESS_SHOW(level, qual.level, fmt_dec);
440 WIRELESS_SHOW(noise, qual.noise, fmt_dec);
441 WIRELESS_SHOW(nwid, discard.nwid, fmt_dec);
442 WIRELESS_SHOW(crypt, discard.code, fmt_dec);
443 WIRELESS_SHOW(fragment, discard.fragment, fmt_dec);
444 WIRELESS_SHOW(misc, discard.misc, fmt_dec);
445 WIRELESS_SHOW(retries, discard.retries, fmt_dec);
446 WIRELESS_SHOW(beacon, miss.beacon, fmt_dec);
447 
448 static struct attribute *wireless_attrs[] = {
449 	&dev_attr_status.attr,
450 	&dev_attr_link.attr,
451 	&dev_attr_level.attr,
452 	&dev_attr_noise.attr,
453 	&dev_attr_nwid.attr,
454 	&dev_attr_crypt.attr,
455 	&dev_attr_fragment.attr,
456 	&dev_attr_retries.attr,
457 	&dev_attr_misc.attr,
458 	&dev_attr_beacon.attr,
459 	NULL
460 };
461 
462 static struct attribute_group wireless_group = {
463 	.name = "wireless",
464 	.attrs = wireless_attrs,
465 };
466 #endif
467 
468 #endif /* CONFIG_SYSFS */
469 
470 #ifdef CONFIG_HOTPLUG
471 static int netdev_uevent(struct device *d, struct kobj_uevent_env *env)
472 {
473 	struct net_device *dev = to_net_dev(d);
474 	int retval;
475 
476 	if (!net_eq(dev_net(dev), &init_net))
477 		return 0;
478 
479 	/* pass interface to uevent. */
480 	retval = add_uevent_var(env, "INTERFACE=%s", dev->name);
481 	if (retval)
482 		goto exit;
483 
484 	/* pass ifindex to uevent.
485 	 * ifindex is useful as it won't change (interface name may change)
486 	 * and is what RtNetlink uses natively. */
487 	retval = add_uevent_var(env, "IFINDEX=%d", dev->ifindex);
488 
489 exit:
490 	return retval;
491 }
492 #endif
493 
494 /*
495  *	netdev_release -- destroy and free a dead device.
496  *	Called when last reference to device kobject is gone.
497  */
498 static void netdev_release(struct device *d)
499 {
500 	struct net_device *dev = to_net_dev(d);
501 
502 	BUG_ON(dev->reg_state != NETREG_RELEASED);
503 
504 	kfree(dev->ifalias);
505 	kfree((char *)dev - dev->padded);
506 }
507 
508 static struct class net_class = {
509 	.name = "net",
510 	.dev_release = netdev_release,
511 #ifdef CONFIG_SYSFS
512 	.dev_attrs = net_class_attributes,
513 #endif /* CONFIG_SYSFS */
514 #ifdef CONFIG_HOTPLUG
515 	.dev_uevent = netdev_uevent,
516 #endif
517 };
518 
519 /* Delete sysfs entries but hold kobject reference until after all
520  * netdev references are gone.
521  */
522 void netdev_unregister_kobject(struct net_device * net)
523 {
524 	struct device *dev = &(net->dev);
525 
526 	kobject_get(&dev->kobj);
527 
528 	if (!net_eq(dev_net(net), &init_net))
529 		return;
530 
531 	device_del(dev);
532 }
533 
534 /* Create sysfs entries for network device. */
535 int netdev_register_kobject(struct net_device *net)
536 {
537 	struct device *dev = &(net->dev);
538 	const struct attribute_group **groups = net->sysfs_groups;
539 
540 	dev->class = &net_class;
541 	dev->platform_data = net;
542 	dev->groups = groups;
543 
544 	dev_set_name(dev, "%s", net->name);
545 
546 #ifdef CONFIG_SYSFS
547 	/* Allow for a device specific group */
548 	if (*groups)
549 		groups++;
550 
551 	*groups++ = &netstat_group;
552 #ifdef CONFIG_WIRELESS_EXT_SYSFS
553 	if (net->ieee80211_ptr)
554 		*groups++ = &wireless_group;
555 #ifdef CONFIG_WIRELESS_EXT
556 	else if (net->wireless_handlers)
557 		*groups++ = &wireless_group;
558 #endif
559 #endif
560 #endif /* CONFIG_SYSFS */
561 
562 	if (!net_eq(dev_net(net), &init_net))
563 		return 0;
564 
565 	return device_add(dev);
566 }
567 
568 int netdev_class_create_file(struct class_attribute *class_attr)
569 {
570 	return class_create_file(&net_class, class_attr);
571 }
572 
573 void netdev_class_remove_file(struct class_attribute *class_attr)
574 {
575 	class_remove_file(&net_class, class_attr);
576 }
577 
578 EXPORT_SYMBOL(netdev_class_create_file);
579 EXPORT_SYMBOL(netdev_class_remove_file);
580 
581 void netdev_initialize_kobject(struct net_device *net)
582 {
583 	struct device *device = &(net->dev);
584 	device_initialize(device);
585 }
586 
587 int netdev_kobject_init(void)
588 {
589 	return class_register(&net_class);
590 }
591