xref: /linux/net/wireless/core.c (revision a33f32244d8550da8b4a26e277ce07d5c6d158b5)
1 /*
2  * This is the linux wireless configuration interface.
3  *
4  * Copyright 2006-2010		Johannes Berg <johannes@sipsolutions.net>
5  */
6 
7 #include <linux/if.h>
8 #include <linux/module.h>
9 #include <linux/err.h>
10 #include <linux/list.h>
11 #include <linux/slab.h>
12 #include <linux/nl80211.h>
13 #include <linux/debugfs.h>
14 #include <linux/notifier.h>
15 #include <linux/device.h>
16 #include <linux/etherdevice.h>
17 #include <linux/rtnetlink.h>
18 #include <linux/sched.h>
19 #include <net/genetlink.h>
20 #include <net/cfg80211.h>
21 #include "nl80211.h"
22 #include "core.h"
23 #include "sysfs.h"
24 #include "debugfs.h"
25 #include "wext-compat.h"
26 #include "ethtool.h"
27 
28 /* name for sysfs, %d is appended */
29 #define PHY_NAME "phy"
30 
31 MODULE_AUTHOR("Johannes Berg");
32 MODULE_LICENSE("GPL");
33 MODULE_DESCRIPTION("wireless configuration support");
34 
35 /* RCU-protected (and cfg80211_mutex for writers) */
36 LIST_HEAD(cfg80211_rdev_list);
37 int cfg80211_rdev_list_generation;
38 
39 DEFINE_MUTEX(cfg80211_mutex);
40 
41 /* for debugfs */
42 static struct dentry *ieee80211_debugfs_dir;
43 
44 /* for the cleanup, scan and event works */
45 struct workqueue_struct *cfg80211_wq;
46 
47 /* requires cfg80211_mutex to be held! */
48 struct cfg80211_registered_device *cfg80211_rdev_by_wiphy_idx(int wiphy_idx)
49 {
50 	struct cfg80211_registered_device *result = NULL, *rdev;
51 
52 	if (!wiphy_idx_valid(wiphy_idx))
53 		return NULL;
54 
55 	assert_cfg80211_lock();
56 
57 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
58 		if (rdev->wiphy_idx == wiphy_idx) {
59 			result = rdev;
60 			break;
61 		}
62 	}
63 
64 	return result;
65 }
66 
67 int get_wiphy_idx(struct wiphy *wiphy)
68 {
69 	struct cfg80211_registered_device *rdev;
70 	if (!wiphy)
71 		return WIPHY_IDX_STALE;
72 	rdev = wiphy_to_dev(wiphy);
73 	return rdev->wiphy_idx;
74 }
75 
76 /* requires cfg80211_rdev_mutex to be held! */
77 struct wiphy *wiphy_idx_to_wiphy(int wiphy_idx)
78 {
79 	struct cfg80211_registered_device *rdev;
80 
81 	if (!wiphy_idx_valid(wiphy_idx))
82 		return NULL;
83 
84 	assert_cfg80211_lock();
85 
86 	rdev = cfg80211_rdev_by_wiphy_idx(wiphy_idx);
87 	if (!rdev)
88 		return NULL;
89 	return &rdev->wiphy;
90 }
91 
92 /* requires cfg80211_mutex to be held! */
93 struct cfg80211_registered_device *
94 __cfg80211_rdev_from_info(struct genl_info *info)
95 {
96 	int ifindex;
97 	struct cfg80211_registered_device *bywiphyidx = NULL, *byifidx = NULL;
98 	struct net_device *dev;
99 	int err = -EINVAL;
100 
101 	assert_cfg80211_lock();
102 
103 	if (info->attrs[NL80211_ATTR_WIPHY]) {
104 		bywiphyidx = cfg80211_rdev_by_wiphy_idx(
105 				nla_get_u32(info->attrs[NL80211_ATTR_WIPHY]));
106 		err = -ENODEV;
107 	}
108 
109 	if (info->attrs[NL80211_ATTR_IFINDEX]) {
110 		ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
111 		dev = dev_get_by_index(genl_info_net(info), ifindex);
112 		if (dev) {
113 			if (dev->ieee80211_ptr)
114 				byifidx =
115 					wiphy_to_dev(dev->ieee80211_ptr->wiphy);
116 			dev_put(dev);
117 		}
118 		err = -ENODEV;
119 	}
120 
121 	if (bywiphyidx && byifidx) {
122 		if (bywiphyidx != byifidx)
123 			return ERR_PTR(-EINVAL);
124 		else
125 			return bywiphyidx; /* == byifidx */
126 	}
127 	if (bywiphyidx)
128 		return bywiphyidx;
129 
130 	if (byifidx)
131 		return byifidx;
132 
133 	return ERR_PTR(err);
134 }
135 
136 struct cfg80211_registered_device *
137 cfg80211_get_dev_from_info(struct genl_info *info)
138 {
139 	struct cfg80211_registered_device *rdev;
140 
141 	mutex_lock(&cfg80211_mutex);
142 	rdev = __cfg80211_rdev_from_info(info);
143 
144 	/* if it is not an error we grab the lock on
145 	 * it to assure it won't be going away while
146 	 * we operate on it */
147 	if (!IS_ERR(rdev))
148 		mutex_lock(&rdev->mtx);
149 
150 	mutex_unlock(&cfg80211_mutex);
151 
152 	return rdev;
153 }
154 
155 struct cfg80211_registered_device *
156 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
157 {
158 	struct cfg80211_registered_device *rdev = ERR_PTR(-ENODEV);
159 	struct net_device *dev;
160 
161 	mutex_lock(&cfg80211_mutex);
162 	dev = dev_get_by_index(net, ifindex);
163 	if (!dev)
164 		goto out;
165 	if (dev->ieee80211_ptr) {
166 		rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
167 		mutex_lock(&rdev->mtx);
168 	} else
169 		rdev = ERR_PTR(-ENODEV);
170 	dev_put(dev);
171  out:
172 	mutex_unlock(&cfg80211_mutex);
173 	return rdev;
174 }
175 
176 /* requires cfg80211_mutex to be held */
177 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
178 			char *newname)
179 {
180 	struct cfg80211_registered_device *rdev2;
181 	int wiphy_idx, taken = -1, result, digits;
182 
183 	assert_cfg80211_lock();
184 
185 	/* prohibit calling the thing phy%d when %d is not its number */
186 	sscanf(newname, PHY_NAME "%d%n", &wiphy_idx, &taken);
187 	if (taken == strlen(newname) && wiphy_idx != rdev->wiphy_idx) {
188 		/* count number of places needed to print wiphy_idx */
189 		digits = 1;
190 		while (wiphy_idx /= 10)
191 			digits++;
192 		/*
193 		 * deny the name if it is phy<idx> where <idx> is printed
194 		 * without leading zeroes. taken == strlen(newname) here
195 		 */
196 		if (taken == strlen(PHY_NAME) + digits)
197 			return -EINVAL;
198 	}
199 
200 
201 	/* Ignore nop renames */
202 	if (strcmp(newname, dev_name(&rdev->wiphy.dev)) == 0)
203 		return 0;
204 
205 	/* Ensure another device does not already have this name. */
206 	list_for_each_entry(rdev2, &cfg80211_rdev_list, list)
207 		if (strcmp(newname, dev_name(&rdev2->wiphy.dev)) == 0)
208 			return -EINVAL;
209 
210 	result = device_rename(&rdev->wiphy.dev, newname);
211 	if (result)
212 		return result;
213 
214 	if (rdev->wiphy.debugfsdir &&
215 	    !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
216 			    rdev->wiphy.debugfsdir,
217 			    rdev->wiphy.debugfsdir->d_parent,
218 			    newname))
219 		printk(KERN_ERR "cfg80211: failed to rename debugfs dir to %s!\n",
220 		       newname);
221 
222 	nl80211_notify_dev_rename(rdev);
223 
224 	return 0;
225 }
226 
227 int cfg80211_switch_netns(struct cfg80211_registered_device *rdev,
228 			  struct net *net)
229 {
230 	struct wireless_dev *wdev;
231 	int err = 0;
232 
233 	if (!(rdev->wiphy.flags & WIPHY_FLAG_NETNS_OK))
234 		return -EOPNOTSUPP;
235 
236 	list_for_each_entry(wdev, &rdev->netdev_list, list) {
237 		wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
238 		err = dev_change_net_namespace(wdev->netdev, net, "wlan%d");
239 		if (err)
240 			break;
241 		wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
242 	}
243 
244 	if (err) {
245 		/* failed -- clean up to old netns */
246 		net = wiphy_net(&rdev->wiphy);
247 
248 		list_for_each_entry_continue_reverse(wdev, &rdev->netdev_list,
249 						     list) {
250 			wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
251 			err = dev_change_net_namespace(wdev->netdev, net,
252 							"wlan%d");
253 			WARN_ON(err);
254 			wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
255 		}
256 	}
257 
258 	wiphy_net_set(&rdev->wiphy, net);
259 
260 	return err;
261 }
262 
263 static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
264 {
265 	struct cfg80211_registered_device *rdev = data;
266 
267 	rdev->ops->rfkill_poll(&rdev->wiphy);
268 }
269 
270 static int cfg80211_rfkill_set_block(void *data, bool blocked)
271 {
272 	struct cfg80211_registered_device *rdev = data;
273 	struct wireless_dev *wdev;
274 
275 	if (!blocked)
276 		return 0;
277 
278 	rtnl_lock();
279 	mutex_lock(&rdev->devlist_mtx);
280 
281 	list_for_each_entry(wdev, &rdev->netdev_list, list)
282 		dev_close(wdev->netdev);
283 
284 	mutex_unlock(&rdev->devlist_mtx);
285 	rtnl_unlock();
286 
287 	return 0;
288 }
289 
290 static void cfg80211_rfkill_sync_work(struct work_struct *work)
291 {
292 	struct cfg80211_registered_device *rdev;
293 
294 	rdev = container_of(work, struct cfg80211_registered_device, rfkill_sync);
295 	cfg80211_rfkill_set_block(rdev, rfkill_blocked(rdev->rfkill));
296 }
297 
298 static void cfg80211_event_work(struct work_struct *work)
299 {
300 	struct cfg80211_registered_device *rdev;
301 
302 	rdev = container_of(work, struct cfg80211_registered_device,
303 			    event_work);
304 
305 	rtnl_lock();
306 	cfg80211_lock_rdev(rdev);
307 
308 	cfg80211_process_rdev_events(rdev);
309 	cfg80211_unlock_rdev(rdev);
310 	rtnl_unlock();
311 }
312 
313 /* exported functions */
314 
315 struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
316 {
317 	static int wiphy_counter;
318 
319 	struct cfg80211_registered_device *rdev;
320 	int alloc_size;
321 
322 	WARN_ON(ops->add_key && (!ops->del_key || !ops->set_default_key));
323 	WARN_ON(ops->auth && (!ops->assoc || !ops->deauth || !ops->disassoc));
324 	WARN_ON(ops->connect && !ops->disconnect);
325 	WARN_ON(ops->join_ibss && !ops->leave_ibss);
326 	WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
327 	WARN_ON(ops->add_station && !ops->del_station);
328 	WARN_ON(ops->add_mpath && !ops->del_mpath);
329 
330 	alloc_size = sizeof(*rdev) + sizeof_priv;
331 
332 	rdev = kzalloc(alloc_size, GFP_KERNEL);
333 	if (!rdev)
334 		return NULL;
335 
336 	rdev->ops = ops;
337 
338 	mutex_lock(&cfg80211_mutex);
339 
340 	rdev->wiphy_idx = wiphy_counter++;
341 
342 	if (unlikely(!wiphy_idx_valid(rdev->wiphy_idx))) {
343 		wiphy_counter--;
344 		mutex_unlock(&cfg80211_mutex);
345 		/* ugh, wrapped! */
346 		kfree(rdev);
347 		return NULL;
348 	}
349 
350 	mutex_unlock(&cfg80211_mutex);
351 
352 	/* give it a proper name */
353 	dev_set_name(&rdev->wiphy.dev, PHY_NAME "%d", rdev->wiphy_idx);
354 
355 	mutex_init(&rdev->mtx);
356 	mutex_init(&rdev->devlist_mtx);
357 	INIT_LIST_HEAD(&rdev->netdev_list);
358 	spin_lock_init(&rdev->bss_lock);
359 	INIT_LIST_HEAD(&rdev->bss_list);
360 	INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
361 
362 #ifdef CONFIG_CFG80211_WEXT
363 	rdev->wiphy.wext = &cfg80211_wext_handler;
364 #endif
365 
366 	device_initialize(&rdev->wiphy.dev);
367 	rdev->wiphy.dev.class = &ieee80211_class;
368 	rdev->wiphy.dev.platform_data = rdev;
369 
370 #ifdef CONFIG_CFG80211_DEFAULT_PS
371 	rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
372 #endif
373 
374 	wiphy_net_set(&rdev->wiphy, &init_net);
375 
376 	rdev->rfkill_ops.set_block = cfg80211_rfkill_set_block;
377 	rdev->rfkill = rfkill_alloc(dev_name(&rdev->wiphy.dev),
378 				   &rdev->wiphy.dev, RFKILL_TYPE_WLAN,
379 				   &rdev->rfkill_ops, rdev);
380 
381 	if (!rdev->rfkill) {
382 		kfree(rdev);
383 		return NULL;
384 	}
385 
386 	INIT_WORK(&rdev->rfkill_sync, cfg80211_rfkill_sync_work);
387 	INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
388 	INIT_WORK(&rdev->event_work, cfg80211_event_work);
389 
390 	init_waitqueue_head(&rdev->dev_wait);
391 
392 	/*
393 	 * Initialize wiphy parameters to IEEE 802.11 MIB default values.
394 	 * Fragmentation and RTS threshold are disabled by default with the
395 	 * special -1 value.
396 	 */
397 	rdev->wiphy.retry_short = 7;
398 	rdev->wiphy.retry_long = 4;
399 	rdev->wiphy.frag_threshold = (u32) -1;
400 	rdev->wiphy.rts_threshold = (u32) -1;
401 	rdev->wiphy.coverage_class = 0;
402 
403 	return &rdev->wiphy;
404 }
405 EXPORT_SYMBOL(wiphy_new);
406 
407 int wiphy_register(struct wiphy *wiphy)
408 {
409 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
410 	int res;
411 	enum ieee80211_band band;
412 	struct ieee80211_supported_band *sband;
413 	bool have_band = false;
414 	int i;
415 	u16 ifmodes = wiphy->interface_modes;
416 
417 	if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
418 		return -EINVAL;
419 
420 	if (WARN_ON(wiphy->addresses &&
421 		    !is_zero_ether_addr(wiphy->perm_addr) &&
422 		    memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
423 			   ETH_ALEN)))
424 		return -EINVAL;
425 
426 	if (wiphy->addresses)
427 		memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
428 
429 	/* sanity check ifmodes */
430 	WARN_ON(!ifmodes);
431 	ifmodes &= ((1 << __NL80211_IFTYPE_AFTER_LAST) - 1) & ~1;
432 	if (WARN_ON(ifmodes != wiphy->interface_modes))
433 		wiphy->interface_modes = ifmodes;
434 
435 	/* sanity check supported bands/channels */
436 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
437 		sband = wiphy->bands[band];
438 		if (!sband)
439 			continue;
440 
441 		sband->band = band;
442 
443 		if (WARN_ON(!sband->n_channels || !sband->n_bitrates))
444 			return -EINVAL;
445 
446 		/*
447 		 * Since we use a u32 for rate bitmaps in
448 		 * ieee80211_get_response_rate, we cannot
449 		 * have more than 32 legacy rates.
450 		 */
451 		if (WARN_ON(sband->n_bitrates > 32))
452 			return -EINVAL;
453 
454 		for (i = 0; i < sband->n_channels; i++) {
455 			sband->channels[i].orig_flags =
456 				sband->channels[i].flags;
457 			sband->channels[i].orig_mag =
458 				sband->channels[i].max_antenna_gain;
459 			sband->channels[i].orig_mpwr =
460 				sband->channels[i].max_power;
461 			sband->channels[i].band = band;
462 		}
463 
464 		have_band = true;
465 	}
466 
467 	if (!have_band) {
468 		WARN_ON(1);
469 		return -EINVAL;
470 	}
471 
472 	/* check and set up bitrates */
473 	ieee80211_set_bitrate_flags(wiphy);
474 
475 	res = device_add(&rdev->wiphy.dev);
476 	if (res)
477 		return res;
478 
479 	res = rfkill_register(rdev->rfkill);
480 	if (res)
481 		goto out_rm_dev;
482 
483 	mutex_lock(&cfg80211_mutex);
484 
485 	/* set up regulatory info */
486 	wiphy_update_regulatory(wiphy, NL80211_REGDOM_SET_BY_CORE);
487 
488 	list_add_rcu(&rdev->list, &cfg80211_rdev_list);
489 	cfg80211_rdev_list_generation++;
490 
491 	mutex_unlock(&cfg80211_mutex);
492 
493 	/* add to debugfs */
494 	rdev->wiphy.debugfsdir =
495 		debugfs_create_dir(wiphy_name(&rdev->wiphy),
496 				   ieee80211_debugfs_dir);
497 	if (IS_ERR(rdev->wiphy.debugfsdir))
498 		rdev->wiphy.debugfsdir = NULL;
499 
500 	if (wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
501 		struct regulatory_request request;
502 
503 		request.wiphy_idx = get_wiphy_idx(wiphy);
504 		request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
505 		request.alpha2[0] = '9';
506 		request.alpha2[1] = '9';
507 
508 		nl80211_send_reg_change_event(&request);
509 	}
510 
511 	cfg80211_debugfs_rdev_add(rdev);
512 
513 	return 0;
514 
515  out_rm_dev:
516 	device_del(&rdev->wiphy.dev);
517 	return res;
518 }
519 EXPORT_SYMBOL(wiphy_register);
520 
521 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
522 {
523 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
524 
525 	if (!rdev->ops->rfkill_poll)
526 		return;
527 	rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
528 	rfkill_resume_polling(rdev->rfkill);
529 }
530 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
531 
532 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
533 {
534 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
535 
536 	rfkill_pause_polling(rdev->rfkill);
537 }
538 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
539 
540 void wiphy_unregister(struct wiphy *wiphy)
541 {
542 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
543 
544 	rfkill_unregister(rdev->rfkill);
545 
546 	/* protect the device list */
547 	mutex_lock(&cfg80211_mutex);
548 
549 	wait_event(rdev->dev_wait, ({
550 		int __count;
551 		mutex_lock(&rdev->devlist_mtx);
552 		__count = rdev->opencount;
553 		mutex_unlock(&rdev->devlist_mtx);
554 		__count == 0;}));
555 
556 	mutex_lock(&rdev->devlist_mtx);
557 	BUG_ON(!list_empty(&rdev->netdev_list));
558 	mutex_unlock(&rdev->devlist_mtx);
559 
560 	/*
561 	 * First remove the hardware from everywhere, this makes
562 	 * it impossible to find from userspace.
563 	 */
564 	debugfs_remove_recursive(rdev->wiphy.debugfsdir);
565 	list_del_rcu(&rdev->list);
566 	synchronize_rcu();
567 
568 	/*
569 	 * Try to grab rdev->mtx. If a command is still in progress,
570 	 * hopefully the driver will refuse it since it's tearing
571 	 * down the device already. We wait for this command to complete
572 	 * before unlinking the item from the list.
573 	 * Note: as codified by the BUG_ON above we cannot get here if
574 	 * a virtual interface is still present. Hence, we can only get
575 	 * to lock contention here if userspace issues a command that
576 	 * identified the hardware by wiphy index.
577 	 */
578 	cfg80211_lock_rdev(rdev);
579 	/* nothing */
580 	cfg80211_unlock_rdev(rdev);
581 
582 	/* If this device got a regulatory hint tell core its
583 	 * free to listen now to a new shiny device regulatory hint */
584 	reg_device_remove(wiphy);
585 
586 	cfg80211_rdev_list_generation++;
587 	device_del(&rdev->wiphy.dev);
588 
589 	mutex_unlock(&cfg80211_mutex);
590 
591 	flush_work(&rdev->scan_done_wk);
592 	cancel_work_sync(&rdev->conn_work);
593 	flush_work(&rdev->event_work);
594 }
595 EXPORT_SYMBOL(wiphy_unregister);
596 
597 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
598 {
599 	struct cfg80211_internal_bss *scan, *tmp;
600 	rfkill_destroy(rdev->rfkill);
601 	mutex_destroy(&rdev->mtx);
602 	mutex_destroy(&rdev->devlist_mtx);
603 	list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
604 		cfg80211_put_bss(&scan->pub);
605 	kfree(rdev);
606 }
607 
608 void wiphy_free(struct wiphy *wiphy)
609 {
610 	put_device(&wiphy->dev);
611 }
612 EXPORT_SYMBOL(wiphy_free);
613 
614 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
615 {
616 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
617 
618 	if (rfkill_set_hw_state(rdev->rfkill, blocked))
619 		schedule_work(&rdev->rfkill_sync);
620 }
621 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
622 
623 static void wdev_cleanup_work(struct work_struct *work)
624 {
625 	struct wireless_dev *wdev;
626 	struct cfg80211_registered_device *rdev;
627 
628 	wdev = container_of(work, struct wireless_dev, cleanup_work);
629 	rdev = wiphy_to_dev(wdev->wiphy);
630 
631 	cfg80211_lock_rdev(rdev);
632 
633 	if (WARN_ON(rdev->scan_req && rdev->scan_req->dev == wdev->netdev)) {
634 		rdev->scan_req->aborted = true;
635 		___cfg80211_scan_done(rdev, true);
636 	}
637 
638 	cfg80211_unlock_rdev(rdev);
639 
640 	mutex_lock(&rdev->devlist_mtx);
641 	rdev->opencount--;
642 	mutex_unlock(&rdev->devlist_mtx);
643 	wake_up(&rdev->dev_wait);
644 
645 	dev_put(wdev->netdev);
646 }
647 
648 static struct device_type wiphy_type = {
649 	.name	= "wlan",
650 };
651 
652 static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
653 					 unsigned long state,
654 					 void *ndev)
655 {
656 	struct net_device *dev = ndev;
657 	struct wireless_dev *wdev = dev->ieee80211_ptr;
658 	struct cfg80211_registered_device *rdev;
659 
660 	if (!wdev)
661 		return NOTIFY_DONE;
662 
663 	rdev = wiphy_to_dev(wdev->wiphy);
664 
665 	WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
666 
667 	switch (state) {
668 	case NETDEV_POST_INIT:
669 		SET_NETDEV_DEVTYPE(dev, &wiphy_type);
670 		break;
671 	case NETDEV_REGISTER:
672 		/*
673 		 * NB: cannot take rdev->mtx here because this may be
674 		 * called within code protected by it when interfaces
675 		 * are added with nl80211.
676 		 */
677 		mutex_init(&wdev->mtx);
678 		INIT_WORK(&wdev->cleanup_work, wdev_cleanup_work);
679 		INIT_LIST_HEAD(&wdev->event_list);
680 		spin_lock_init(&wdev->event_lock);
681 		INIT_LIST_HEAD(&wdev->action_registrations);
682 		spin_lock_init(&wdev->action_registrations_lock);
683 
684 		mutex_lock(&rdev->devlist_mtx);
685 		list_add_rcu(&wdev->list, &rdev->netdev_list);
686 		rdev->devlist_generation++;
687 		/* can only change netns with wiphy */
688 		dev->features |= NETIF_F_NETNS_LOCAL;
689 
690 		if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
691 				      "phy80211")) {
692 			printk(KERN_ERR "wireless: failed to add phy80211 "
693 				"symlink to netdev!\n");
694 		}
695 		wdev->netdev = dev;
696 		wdev->sme_state = CFG80211_SME_IDLE;
697 		mutex_unlock(&rdev->devlist_mtx);
698 #ifdef CONFIG_CFG80211_WEXT
699 		wdev->wext.default_key = -1;
700 		wdev->wext.default_mgmt_key = -1;
701 		wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
702 #endif
703 
704 		if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
705 			wdev->ps = true;
706 		else
707 			wdev->ps = false;
708 		wdev->ps_timeout = 100;
709 		if (rdev->ops->set_power_mgmt)
710 			if (rdev->ops->set_power_mgmt(wdev->wiphy, dev,
711 						      wdev->ps,
712 						      wdev->ps_timeout)) {
713 				/* assume this means it's off */
714 				wdev->ps = false;
715 			}
716 
717 		if (!dev->ethtool_ops)
718 			dev->ethtool_ops = &cfg80211_ethtool_ops;
719 
720 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
721 		     wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
722 			dev->priv_flags |= IFF_DONT_BRIDGE;
723 		break;
724 	case NETDEV_GOING_DOWN:
725 		switch (wdev->iftype) {
726 		case NL80211_IFTYPE_ADHOC:
727 			cfg80211_leave_ibss(rdev, dev, true);
728 			break;
729 		case NL80211_IFTYPE_STATION:
730 			wdev_lock(wdev);
731 #ifdef CONFIG_CFG80211_WEXT
732 			kfree(wdev->wext.ie);
733 			wdev->wext.ie = NULL;
734 			wdev->wext.ie_len = 0;
735 			wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
736 #endif
737 			__cfg80211_disconnect(rdev, dev,
738 					      WLAN_REASON_DEAUTH_LEAVING, true);
739 			cfg80211_mlme_down(rdev, dev);
740 			wdev_unlock(wdev);
741 			break;
742 		default:
743 			break;
744 		}
745 		break;
746 	case NETDEV_DOWN:
747 		dev_hold(dev);
748 		queue_work(cfg80211_wq, &wdev->cleanup_work);
749 		break;
750 	case NETDEV_UP:
751 		/*
752 		 * If we have a really quick DOWN/UP succession we may
753 		 * have this work still pending ... cancel it and see
754 		 * if it was pending, in which case we need to account
755 		 * for some of the work it would have done.
756 		 */
757 		if (cancel_work_sync(&wdev->cleanup_work)) {
758 			mutex_lock(&rdev->devlist_mtx);
759 			rdev->opencount--;
760 			mutex_unlock(&rdev->devlist_mtx);
761 			dev_put(dev);
762 		}
763 		cfg80211_lock_rdev(rdev);
764 		mutex_lock(&rdev->devlist_mtx);
765 #ifdef CONFIG_CFG80211_WEXT
766 		wdev_lock(wdev);
767 		switch (wdev->iftype) {
768 		case NL80211_IFTYPE_ADHOC:
769 			cfg80211_ibss_wext_join(rdev, wdev);
770 			break;
771 		case NL80211_IFTYPE_STATION:
772 			cfg80211_mgd_wext_connect(rdev, wdev);
773 			break;
774 		default:
775 			break;
776 		}
777 		wdev_unlock(wdev);
778 #endif
779 		rdev->opencount++;
780 		mutex_unlock(&rdev->devlist_mtx);
781 		cfg80211_unlock_rdev(rdev);
782 		break;
783 	case NETDEV_UNREGISTER:
784 		/*
785 		 * NB: cannot take rdev->mtx here because this may be
786 		 * called within code protected by it when interfaces
787 		 * are removed with nl80211.
788 		 */
789 		mutex_lock(&rdev->devlist_mtx);
790 		/*
791 		 * It is possible to get NETDEV_UNREGISTER
792 		 * multiple times. To detect that, check
793 		 * that the interface is still on the list
794 		 * of registered interfaces, and only then
795 		 * remove and clean it up.
796 		 */
797 		if (!list_empty(&wdev->list)) {
798 			sysfs_remove_link(&dev->dev.kobj, "phy80211");
799 			list_del_rcu(&wdev->list);
800 			rdev->devlist_generation++;
801 			cfg80211_mlme_purge_actions(wdev);
802 #ifdef CONFIG_CFG80211_WEXT
803 			kfree(wdev->wext.keys);
804 #endif
805 		}
806 		mutex_unlock(&rdev->devlist_mtx);
807 		/*
808 		 * synchronise (so that we won't find this netdev
809 		 * from other code any more) and then clear the list
810 		 * head so that the above code can safely check for
811 		 * !list_empty() to avoid double-cleanup.
812 		 */
813 		synchronize_rcu();
814 		INIT_LIST_HEAD(&wdev->list);
815 		break;
816 	case NETDEV_PRE_UP:
817 		if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
818 			return notifier_from_errno(-EOPNOTSUPP);
819 		if (rfkill_blocked(rdev->rfkill))
820 			return notifier_from_errno(-ERFKILL);
821 		break;
822 	}
823 
824 	return NOTIFY_DONE;
825 }
826 
827 static struct notifier_block cfg80211_netdev_notifier = {
828 	.notifier_call = cfg80211_netdev_notifier_call,
829 };
830 
831 static void __net_exit cfg80211_pernet_exit(struct net *net)
832 {
833 	struct cfg80211_registered_device *rdev;
834 
835 	rtnl_lock();
836 	mutex_lock(&cfg80211_mutex);
837 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
838 		if (net_eq(wiphy_net(&rdev->wiphy), net))
839 			WARN_ON(cfg80211_switch_netns(rdev, &init_net));
840 	}
841 	mutex_unlock(&cfg80211_mutex);
842 	rtnl_unlock();
843 }
844 
845 static struct pernet_operations cfg80211_pernet_ops = {
846 	.exit = cfg80211_pernet_exit,
847 };
848 
849 static int __init cfg80211_init(void)
850 {
851 	int err;
852 
853 	err = register_pernet_device(&cfg80211_pernet_ops);
854 	if (err)
855 		goto out_fail_pernet;
856 
857 	err = wiphy_sysfs_init();
858 	if (err)
859 		goto out_fail_sysfs;
860 
861 	err = register_netdevice_notifier(&cfg80211_netdev_notifier);
862 	if (err)
863 		goto out_fail_notifier;
864 
865 	err = nl80211_init();
866 	if (err)
867 		goto out_fail_nl80211;
868 
869 	ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
870 
871 	err = regulatory_init();
872 	if (err)
873 		goto out_fail_reg;
874 
875 	cfg80211_wq = create_singlethread_workqueue("cfg80211");
876 	if (!cfg80211_wq)
877 		goto out_fail_wq;
878 
879 	return 0;
880 
881 out_fail_wq:
882 	regulatory_exit();
883 out_fail_reg:
884 	debugfs_remove(ieee80211_debugfs_dir);
885 out_fail_nl80211:
886 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
887 out_fail_notifier:
888 	wiphy_sysfs_exit();
889 out_fail_sysfs:
890 	unregister_pernet_device(&cfg80211_pernet_ops);
891 out_fail_pernet:
892 	return err;
893 }
894 subsys_initcall(cfg80211_init);
895 
896 static void cfg80211_exit(void)
897 {
898 	debugfs_remove(ieee80211_debugfs_dir);
899 	nl80211_exit();
900 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
901 	wiphy_sysfs_exit();
902 	regulatory_exit();
903 	unregister_pernet_device(&cfg80211_pernet_ops);
904 	destroy_workqueue(cfg80211_wq);
905 }
906 module_exit(cfg80211_exit);
907