xref: /openbmc/linux/net/wireless/core.c (revision 9d749629)
1 /*
2  * This is the linux wireless configuration interface.
3  *
4  * Copyright 2006-2010		Johannes Berg <johannes@sipsolutions.net>
5  */
6 
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8 
9 #include <linux/if.h>
10 #include <linux/module.h>
11 #include <linux/err.h>
12 #include <linux/list.h>
13 #include <linux/slab.h>
14 #include <linux/nl80211.h>
15 #include <linux/debugfs.h>
16 #include <linux/notifier.h>
17 #include <linux/device.h>
18 #include <linux/etherdevice.h>
19 #include <linux/rtnetlink.h>
20 #include <linux/sched.h>
21 #include <net/genetlink.h>
22 #include <net/cfg80211.h>
23 #include "nl80211.h"
24 #include "core.h"
25 #include "sysfs.h"
26 #include "debugfs.h"
27 #include "wext-compat.h"
28 #include "ethtool.h"
29 #include "rdev-ops.h"
30 
31 /* name for sysfs, %d is appended */
32 #define PHY_NAME "phy"
33 
34 MODULE_AUTHOR("Johannes Berg");
35 MODULE_LICENSE("GPL");
36 MODULE_DESCRIPTION("wireless configuration support");
37 
38 /* RCU-protected (and cfg80211_mutex for writers) */
39 LIST_HEAD(cfg80211_rdev_list);
40 int cfg80211_rdev_list_generation;
41 
42 DEFINE_MUTEX(cfg80211_mutex);
43 
44 /* for debugfs */
45 static struct dentry *ieee80211_debugfs_dir;
46 
47 /* for the cleanup, scan and event works */
48 struct workqueue_struct *cfg80211_wq;
49 
50 static bool cfg80211_disable_40mhz_24ghz;
51 module_param(cfg80211_disable_40mhz_24ghz, bool, 0644);
52 MODULE_PARM_DESC(cfg80211_disable_40mhz_24ghz,
53 		 "Disable 40MHz support in the 2.4GHz band");
54 
55 /* requires cfg80211_mutex to be held! */
56 struct cfg80211_registered_device *cfg80211_rdev_by_wiphy_idx(int wiphy_idx)
57 {
58 	struct cfg80211_registered_device *result = NULL, *rdev;
59 
60 	assert_cfg80211_lock();
61 
62 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
63 		if (rdev->wiphy_idx == wiphy_idx) {
64 			result = rdev;
65 			break;
66 		}
67 	}
68 
69 	return result;
70 }
71 
72 int get_wiphy_idx(struct wiphy *wiphy)
73 {
74 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
75 
76 	return rdev->wiphy_idx;
77 }
78 
79 /* requires cfg80211_rdev_mutex to be held! */
80 struct wiphy *wiphy_idx_to_wiphy(int wiphy_idx)
81 {
82 	struct cfg80211_registered_device *rdev;
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 struct cfg80211_registered_device *
93 cfg80211_get_dev_from_ifindex(struct net *net, int ifindex)
94 {
95 	struct cfg80211_registered_device *rdev = ERR_PTR(-ENODEV);
96 	struct net_device *dev;
97 
98 	mutex_lock(&cfg80211_mutex);
99 	dev = dev_get_by_index(net, ifindex);
100 	if (!dev)
101 		goto out;
102 	if (dev->ieee80211_ptr) {
103 		rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
104 		mutex_lock(&rdev->mtx);
105 	} else
106 		rdev = ERR_PTR(-ENODEV);
107 	dev_put(dev);
108  out:
109 	mutex_unlock(&cfg80211_mutex);
110 	return rdev;
111 }
112 
113 /* requires cfg80211_mutex to be held */
114 int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
115 			char *newname)
116 {
117 	struct cfg80211_registered_device *rdev2;
118 	int wiphy_idx, taken = -1, result, digits;
119 
120 	assert_cfg80211_lock();
121 
122 	/* prohibit calling the thing phy%d when %d is not its number */
123 	sscanf(newname, PHY_NAME "%d%n", &wiphy_idx, &taken);
124 	if (taken == strlen(newname) && wiphy_idx != rdev->wiphy_idx) {
125 		/* count number of places needed to print wiphy_idx */
126 		digits = 1;
127 		while (wiphy_idx /= 10)
128 			digits++;
129 		/*
130 		 * deny the name if it is phy<idx> where <idx> is printed
131 		 * without leading zeroes. taken == strlen(newname) here
132 		 */
133 		if (taken == strlen(PHY_NAME) + digits)
134 			return -EINVAL;
135 	}
136 
137 
138 	/* Ignore nop renames */
139 	if (strcmp(newname, dev_name(&rdev->wiphy.dev)) == 0)
140 		return 0;
141 
142 	/* Ensure another device does not already have this name. */
143 	list_for_each_entry(rdev2, &cfg80211_rdev_list, list)
144 		if (strcmp(newname, dev_name(&rdev2->wiphy.dev)) == 0)
145 			return -EINVAL;
146 
147 	result = device_rename(&rdev->wiphy.dev, newname);
148 	if (result)
149 		return result;
150 
151 	if (rdev->wiphy.debugfsdir &&
152 	    !debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
153 			    rdev->wiphy.debugfsdir,
154 			    rdev->wiphy.debugfsdir->d_parent,
155 			    newname))
156 		pr_err("failed to rename debugfs dir to %s!\n", newname);
157 
158 	nl80211_notify_dev_rename(rdev);
159 
160 	return 0;
161 }
162 
163 int cfg80211_switch_netns(struct cfg80211_registered_device *rdev,
164 			  struct net *net)
165 {
166 	struct wireless_dev *wdev;
167 	int err = 0;
168 
169 	if (!(rdev->wiphy.flags & WIPHY_FLAG_NETNS_OK))
170 		return -EOPNOTSUPP;
171 
172 	list_for_each_entry(wdev, &rdev->wdev_list, list) {
173 		if (!wdev->netdev)
174 			continue;
175 		wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
176 		err = dev_change_net_namespace(wdev->netdev, net, "wlan%d");
177 		if (err)
178 			break;
179 		wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
180 	}
181 
182 	if (err) {
183 		/* failed -- clean up to old netns */
184 		net = wiphy_net(&rdev->wiphy);
185 
186 		list_for_each_entry_continue_reverse(wdev, &rdev->wdev_list,
187 						     list) {
188 			if (!wdev->netdev)
189 				continue;
190 			wdev->netdev->features &= ~NETIF_F_NETNS_LOCAL;
191 			err = dev_change_net_namespace(wdev->netdev, net,
192 							"wlan%d");
193 			WARN_ON(err);
194 			wdev->netdev->features |= NETIF_F_NETNS_LOCAL;
195 		}
196 
197 		return err;
198 	}
199 
200 	wiphy_net_set(&rdev->wiphy, net);
201 
202 	err = device_rename(&rdev->wiphy.dev, dev_name(&rdev->wiphy.dev));
203 	WARN_ON(err);
204 
205 	return 0;
206 }
207 
208 static void cfg80211_rfkill_poll(struct rfkill *rfkill, void *data)
209 {
210 	struct cfg80211_registered_device *rdev = data;
211 
212 	rdev_rfkill_poll(rdev);
213 }
214 
215 static int cfg80211_rfkill_set_block(void *data, bool blocked)
216 {
217 	struct cfg80211_registered_device *rdev = data;
218 	struct wireless_dev *wdev;
219 
220 	if (!blocked)
221 		return 0;
222 
223 	rtnl_lock();
224 	mutex_lock(&rdev->devlist_mtx);
225 
226 	list_for_each_entry(wdev, &rdev->wdev_list, list) {
227 		if (wdev->netdev) {
228 			dev_close(wdev->netdev);
229 			continue;
230 		}
231 		/* otherwise, check iftype */
232 		switch (wdev->iftype) {
233 		case NL80211_IFTYPE_P2P_DEVICE:
234 			if (!wdev->p2p_started)
235 				break;
236 			rdev_stop_p2p_device(rdev, wdev);
237 			wdev->p2p_started = false;
238 			rdev->opencount--;
239 			break;
240 		default:
241 			break;
242 		}
243 	}
244 
245 	mutex_unlock(&rdev->devlist_mtx);
246 	rtnl_unlock();
247 
248 	return 0;
249 }
250 
251 static void cfg80211_rfkill_sync_work(struct work_struct *work)
252 {
253 	struct cfg80211_registered_device *rdev;
254 
255 	rdev = container_of(work, struct cfg80211_registered_device, rfkill_sync);
256 	cfg80211_rfkill_set_block(rdev, rfkill_blocked(rdev->rfkill));
257 }
258 
259 static void cfg80211_event_work(struct work_struct *work)
260 {
261 	struct cfg80211_registered_device *rdev;
262 
263 	rdev = container_of(work, struct cfg80211_registered_device,
264 			    event_work);
265 
266 	rtnl_lock();
267 	cfg80211_lock_rdev(rdev);
268 
269 	cfg80211_process_rdev_events(rdev);
270 	cfg80211_unlock_rdev(rdev);
271 	rtnl_unlock();
272 }
273 
274 /* exported functions */
275 
276 struct wiphy *wiphy_new(const struct cfg80211_ops *ops, int sizeof_priv)
277 {
278 	static int wiphy_counter;
279 
280 	struct cfg80211_registered_device *rdev;
281 	int alloc_size;
282 
283 	WARN_ON(ops->add_key && (!ops->del_key || !ops->set_default_key));
284 	WARN_ON(ops->auth && (!ops->assoc || !ops->deauth || !ops->disassoc));
285 	WARN_ON(ops->connect && !ops->disconnect);
286 	WARN_ON(ops->join_ibss && !ops->leave_ibss);
287 	WARN_ON(ops->add_virtual_intf && !ops->del_virtual_intf);
288 	WARN_ON(ops->add_station && !ops->del_station);
289 	WARN_ON(ops->add_mpath && !ops->del_mpath);
290 	WARN_ON(ops->join_mesh && !ops->leave_mesh);
291 
292 	alloc_size = sizeof(*rdev) + sizeof_priv;
293 
294 	rdev = kzalloc(alloc_size, GFP_KERNEL);
295 	if (!rdev)
296 		return NULL;
297 
298 	rdev->ops = ops;
299 
300 	mutex_lock(&cfg80211_mutex);
301 
302 	rdev->wiphy_idx = wiphy_counter++;
303 
304 	if (unlikely(rdev->wiphy_idx < 0)) {
305 		wiphy_counter--;
306 		mutex_unlock(&cfg80211_mutex);
307 		/* ugh, wrapped! */
308 		kfree(rdev);
309 		return NULL;
310 	}
311 
312 	mutex_unlock(&cfg80211_mutex);
313 
314 	/* give it a proper name */
315 	dev_set_name(&rdev->wiphy.dev, PHY_NAME "%d", rdev->wiphy_idx);
316 
317 	mutex_init(&rdev->mtx);
318 	mutex_init(&rdev->devlist_mtx);
319 	mutex_init(&rdev->sched_scan_mtx);
320 	INIT_LIST_HEAD(&rdev->wdev_list);
321 	INIT_LIST_HEAD(&rdev->beacon_registrations);
322 	spin_lock_init(&rdev->beacon_registrations_lock);
323 	spin_lock_init(&rdev->bss_lock);
324 	INIT_LIST_HEAD(&rdev->bss_list);
325 	INIT_WORK(&rdev->scan_done_wk, __cfg80211_scan_done);
326 	INIT_WORK(&rdev->sched_scan_results_wk, __cfg80211_sched_scan_results);
327 	INIT_DELAYED_WORK(&rdev->dfs_update_channels_wk,
328 			  cfg80211_dfs_channels_update_work);
329 #ifdef CONFIG_CFG80211_WEXT
330 	rdev->wiphy.wext = &cfg80211_wext_handler;
331 #endif
332 
333 	device_initialize(&rdev->wiphy.dev);
334 	rdev->wiphy.dev.class = &ieee80211_class;
335 	rdev->wiphy.dev.platform_data = rdev;
336 
337 #ifdef CONFIG_CFG80211_DEFAULT_PS
338 	rdev->wiphy.flags |= WIPHY_FLAG_PS_ON_BY_DEFAULT;
339 #endif
340 
341 	wiphy_net_set(&rdev->wiphy, &init_net);
342 
343 	rdev->rfkill_ops.set_block = cfg80211_rfkill_set_block;
344 	rdev->rfkill = rfkill_alloc(dev_name(&rdev->wiphy.dev),
345 				   &rdev->wiphy.dev, RFKILL_TYPE_WLAN,
346 				   &rdev->rfkill_ops, rdev);
347 
348 	if (!rdev->rfkill) {
349 		kfree(rdev);
350 		return NULL;
351 	}
352 
353 	INIT_WORK(&rdev->rfkill_sync, cfg80211_rfkill_sync_work);
354 	INIT_WORK(&rdev->conn_work, cfg80211_conn_work);
355 	INIT_WORK(&rdev->event_work, cfg80211_event_work);
356 
357 	init_waitqueue_head(&rdev->dev_wait);
358 
359 	/*
360 	 * Initialize wiphy parameters to IEEE 802.11 MIB default values.
361 	 * Fragmentation and RTS threshold are disabled by default with the
362 	 * special -1 value.
363 	 */
364 	rdev->wiphy.retry_short = 7;
365 	rdev->wiphy.retry_long = 4;
366 	rdev->wiphy.frag_threshold = (u32) -1;
367 	rdev->wiphy.rts_threshold = (u32) -1;
368 	rdev->wiphy.coverage_class = 0;
369 
370 	rdev->wiphy.features = NL80211_FEATURE_SCAN_FLUSH |
371 			       NL80211_FEATURE_ADVERTISE_CHAN_LIMITS;
372 
373 	return &rdev->wiphy;
374 }
375 EXPORT_SYMBOL(wiphy_new);
376 
377 static int wiphy_verify_combinations(struct wiphy *wiphy)
378 {
379 	const struct ieee80211_iface_combination *c;
380 	int i, j;
381 
382 	for (i = 0; i < wiphy->n_iface_combinations; i++) {
383 		u32 cnt = 0;
384 		u16 all_iftypes = 0;
385 
386 		c = &wiphy->iface_combinations[i];
387 
388 		/*
389 		 * Combinations with just one interface aren't real,
390 		 * however we make an exception for DFS.
391 		 */
392 		if (WARN_ON((c->max_interfaces < 2) && !c->radar_detect_widths))
393 			return -EINVAL;
394 
395 		/* Need at least one channel */
396 		if (WARN_ON(!c->num_different_channels))
397 			return -EINVAL;
398 
399 		/*
400 		 * Put a sane limit on maximum number of different
401 		 * channels to simplify channel accounting code.
402 		 */
403 		if (WARN_ON(c->num_different_channels >
404 				CFG80211_MAX_NUM_DIFFERENT_CHANNELS))
405 			return -EINVAL;
406 
407 		/* DFS only works on one channel. */
408 		if (WARN_ON(c->radar_detect_widths &&
409 			    (c->num_different_channels > 1)))
410 			return -EINVAL;
411 
412 		if (WARN_ON(!c->n_limits))
413 			return -EINVAL;
414 
415 		for (j = 0; j < c->n_limits; j++) {
416 			u16 types = c->limits[j].types;
417 
418 			/*
419 			 * interface types shouldn't overlap, this is
420 			 * used in cfg80211_can_change_interface()
421 			 */
422 			if (WARN_ON(types & all_iftypes))
423 				return -EINVAL;
424 			all_iftypes |= types;
425 
426 			if (WARN_ON(!c->limits[j].max))
427 				return -EINVAL;
428 
429 			/* Shouldn't list software iftypes in combinations! */
430 			if (WARN_ON(wiphy->software_iftypes & types))
431 				return -EINVAL;
432 
433 			/* Only a single P2P_DEVICE can be allowed */
434 			if (WARN_ON(types & BIT(NL80211_IFTYPE_P2P_DEVICE) &&
435 				    c->limits[j].max > 1))
436 				return -EINVAL;
437 
438 			cnt += c->limits[j].max;
439 			/*
440 			 * Don't advertise an unsupported type
441 			 * in a combination.
442 			 */
443 			if (WARN_ON((wiphy->interface_modes & types) != types))
444 				return -EINVAL;
445 		}
446 
447 		/* You can't even choose that many! */
448 		if (WARN_ON(cnt < c->max_interfaces))
449 			return -EINVAL;
450 	}
451 
452 	return 0;
453 }
454 
455 int wiphy_register(struct wiphy *wiphy)
456 {
457 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
458 	int res;
459 	enum ieee80211_band band;
460 	struct ieee80211_supported_band *sband;
461 	bool have_band = false;
462 	int i;
463 	u16 ifmodes = wiphy->interface_modes;
464 
465 #ifdef CONFIG_PM
466 	if (WARN_ON((wiphy->wowlan.flags & WIPHY_WOWLAN_GTK_REKEY_FAILURE) &&
467 		    !(wiphy->wowlan.flags & WIPHY_WOWLAN_SUPPORTS_GTK_REKEY)))
468 		return -EINVAL;
469 #endif
470 
471 	if (WARN_ON(wiphy->ap_sme_capa &&
472 		    !(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME)))
473 		return -EINVAL;
474 
475 	if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
476 		return -EINVAL;
477 
478 	if (WARN_ON(wiphy->addresses &&
479 		    !is_zero_ether_addr(wiphy->perm_addr) &&
480 		    memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
481 			   ETH_ALEN)))
482 		return -EINVAL;
483 
484 	if (WARN_ON(wiphy->max_acl_mac_addrs &&
485 		    (!(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME) ||
486 		     !rdev->ops->set_mac_acl)))
487 		return -EINVAL;
488 
489 	if (wiphy->addresses)
490 		memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
491 
492 	/* sanity check ifmodes */
493 	WARN_ON(!ifmodes);
494 	ifmodes &= ((1 << NUM_NL80211_IFTYPES) - 1) & ~1;
495 	if (WARN_ON(ifmodes != wiphy->interface_modes))
496 		wiphy->interface_modes = ifmodes;
497 
498 	res = wiphy_verify_combinations(wiphy);
499 	if (res)
500 		return res;
501 
502 	/* sanity check supported bands/channels */
503 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
504 		sband = wiphy->bands[band];
505 		if (!sband)
506 			continue;
507 
508 		sband->band = band;
509 		if (WARN_ON(!sband->n_channels))
510 			return -EINVAL;
511 		/*
512 		 * on 60gHz band, there are no legacy rates, so
513 		 * n_bitrates is 0
514 		 */
515 		if (WARN_ON(band != IEEE80211_BAND_60GHZ &&
516 			    !sband->n_bitrates))
517 			return -EINVAL;
518 
519 		/*
520 		 * Since cfg80211_disable_40mhz_24ghz is global, we can
521 		 * modify the sband's ht data even if the driver uses a
522 		 * global structure for that.
523 		 */
524 		if (cfg80211_disable_40mhz_24ghz &&
525 		    band == IEEE80211_BAND_2GHZ &&
526 		    sband->ht_cap.ht_supported) {
527 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
528 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SGI_40;
529 		}
530 
531 		/*
532 		 * Since we use a u32 for rate bitmaps in
533 		 * ieee80211_get_response_rate, we cannot
534 		 * have more than 32 legacy rates.
535 		 */
536 		if (WARN_ON(sband->n_bitrates > 32))
537 			return -EINVAL;
538 
539 		for (i = 0; i < sband->n_channels; i++) {
540 			sband->channels[i].orig_flags =
541 				sband->channels[i].flags;
542 			sband->channels[i].orig_mag = INT_MAX;
543 			sband->channels[i].orig_mpwr =
544 				sband->channels[i].max_power;
545 			sband->channels[i].band = band;
546 		}
547 
548 		have_band = true;
549 	}
550 
551 	if (!have_band) {
552 		WARN_ON(1);
553 		return -EINVAL;
554 	}
555 
556 #ifdef CONFIG_PM
557 	if (rdev->wiphy.wowlan.n_patterns) {
558 		if (WARN_ON(!rdev->wiphy.wowlan.pattern_min_len ||
559 			    rdev->wiphy.wowlan.pattern_min_len >
560 			    rdev->wiphy.wowlan.pattern_max_len))
561 			return -EINVAL;
562 	}
563 #endif
564 
565 	/* check and set up bitrates */
566 	ieee80211_set_bitrate_flags(wiphy);
567 
568 	mutex_lock(&cfg80211_mutex);
569 
570 	res = device_add(&rdev->wiphy.dev);
571 	if (res) {
572 		mutex_unlock(&cfg80211_mutex);
573 		return res;
574 	}
575 
576 	/* set up regulatory info */
577 	wiphy_regulatory_register(wiphy);
578 
579 	list_add_rcu(&rdev->list, &cfg80211_rdev_list);
580 	cfg80211_rdev_list_generation++;
581 
582 	/* add to debugfs */
583 	rdev->wiphy.debugfsdir =
584 		debugfs_create_dir(wiphy_name(&rdev->wiphy),
585 				   ieee80211_debugfs_dir);
586 	if (IS_ERR(rdev->wiphy.debugfsdir))
587 		rdev->wiphy.debugfsdir = NULL;
588 
589 	if (wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
590 		struct regulatory_request request;
591 
592 		request.wiphy_idx = get_wiphy_idx(wiphy);
593 		request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
594 		request.alpha2[0] = '9';
595 		request.alpha2[1] = '9';
596 
597 		nl80211_send_reg_change_event(&request);
598 	}
599 
600 	cfg80211_debugfs_rdev_add(rdev);
601 	mutex_unlock(&cfg80211_mutex);
602 
603 	/*
604 	 * due to a locking dependency this has to be outside of the
605 	 * cfg80211_mutex lock
606 	 */
607 	res = rfkill_register(rdev->rfkill);
608 	if (res)
609 		goto out_rm_dev;
610 
611 	rtnl_lock();
612 	rdev->wiphy.registered = true;
613 	rtnl_unlock();
614 	return 0;
615 
616 out_rm_dev:
617 	device_del(&rdev->wiphy.dev);
618 	return res;
619 }
620 EXPORT_SYMBOL(wiphy_register);
621 
622 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
623 {
624 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
625 
626 	if (!rdev->ops->rfkill_poll)
627 		return;
628 	rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
629 	rfkill_resume_polling(rdev->rfkill);
630 }
631 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
632 
633 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
634 {
635 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
636 
637 	rfkill_pause_polling(rdev->rfkill);
638 }
639 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
640 
641 void wiphy_unregister(struct wiphy *wiphy)
642 {
643 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
644 
645 	rtnl_lock();
646 	rdev->wiphy.registered = false;
647 	rtnl_unlock();
648 
649 	rfkill_unregister(rdev->rfkill);
650 
651 	/* protect the device list */
652 	mutex_lock(&cfg80211_mutex);
653 
654 	wait_event(rdev->dev_wait, ({
655 		int __count;
656 		mutex_lock(&rdev->devlist_mtx);
657 		__count = rdev->opencount;
658 		mutex_unlock(&rdev->devlist_mtx);
659 		__count == 0; }));
660 
661 	mutex_lock(&rdev->devlist_mtx);
662 	BUG_ON(!list_empty(&rdev->wdev_list));
663 	mutex_unlock(&rdev->devlist_mtx);
664 
665 	/*
666 	 * First remove the hardware from everywhere, this makes
667 	 * it impossible to find from userspace.
668 	 */
669 	debugfs_remove_recursive(rdev->wiphy.debugfsdir);
670 	list_del_rcu(&rdev->list);
671 	synchronize_rcu();
672 
673 	/*
674 	 * Try to grab rdev->mtx. If a command is still in progress,
675 	 * hopefully the driver will refuse it since it's tearing
676 	 * down the device already. We wait for this command to complete
677 	 * before unlinking the item from the list.
678 	 * Note: as codified by the BUG_ON above we cannot get here if
679 	 * a virtual interface is still present. Hence, we can only get
680 	 * to lock contention here if userspace issues a command that
681 	 * identified the hardware by wiphy index.
682 	 */
683 	cfg80211_lock_rdev(rdev);
684 	/* nothing */
685 	cfg80211_unlock_rdev(rdev);
686 
687 	/*
688 	 * If this device got a regulatory hint tell core its
689 	 * free to listen now to a new shiny device regulatory hint
690 	 */
691 	wiphy_regulatory_deregister(wiphy);
692 
693 	cfg80211_rdev_list_generation++;
694 	device_del(&rdev->wiphy.dev);
695 
696 	mutex_unlock(&cfg80211_mutex);
697 
698 	flush_work(&rdev->scan_done_wk);
699 	cancel_work_sync(&rdev->conn_work);
700 	flush_work(&rdev->event_work);
701 	cancel_delayed_work_sync(&rdev->dfs_update_channels_wk);
702 
703 	if (rdev->wowlan && rdev->ops->set_wakeup)
704 		rdev_set_wakeup(rdev, false);
705 	cfg80211_rdev_free_wowlan(rdev);
706 }
707 EXPORT_SYMBOL(wiphy_unregister);
708 
709 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
710 {
711 	struct cfg80211_internal_bss *scan, *tmp;
712 	struct cfg80211_beacon_registration *reg, *treg;
713 	rfkill_destroy(rdev->rfkill);
714 	mutex_destroy(&rdev->mtx);
715 	mutex_destroy(&rdev->devlist_mtx);
716 	mutex_destroy(&rdev->sched_scan_mtx);
717 	list_for_each_entry_safe(reg, treg, &rdev->beacon_registrations, list) {
718 		list_del(&reg->list);
719 		kfree(reg);
720 	}
721 	list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
722 		cfg80211_put_bss(&rdev->wiphy, &scan->pub);
723 	kfree(rdev);
724 }
725 
726 void wiphy_free(struct wiphy *wiphy)
727 {
728 	put_device(&wiphy->dev);
729 }
730 EXPORT_SYMBOL(wiphy_free);
731 
732 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
733 {
734 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
735 
736 	if (rfkill_set_hw_state(rdev->rfkill, blocked))
737 		schedule_work(&rdev->rfkill_sync);
738 }
739 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
740 
741 static void wdev_cleanup_work(struct work_struct *work)
742 {
743 	struct wireless_dev *wdev;
744 	struct cfg80211_registered_device *rdev;
745 
746 	wdev = container_of(work, struct wireless_dev, cleanup_work);
747 	rdev = wiphy_to_dev(wdev->wiphy);
748 
749 	cfg80211_lock_rdev(rdev);
750 
751 	if (WARN_ON(rdev->scan_req && rdev->scan_req->wdev == wdev)) {
752 		rdev->scan_req->aborted = true;
753 		___cfg80211_scan_done(rdev, true);
754 	}
755 
756 	cfg80211_unlock_rdev(rdev);
757 
758 	mutex_lock(&rdev->sched_scan_mtx);
759 
760 	if (WARN_ON(rdev->sched_scan_req &&
761 		    rdev->sched_scan_req->dev == wdev->netdev)) {
762 		__cfg80211_stop_sched_scan(rdev, false);
763 	}
764 
765 	mutex_unlock(&rdev->sched_scan_mtx);
766 
767 	mutex_lock(&rdev->devlist_mtx);
768 	rdev->opencount--;
769 	mutex_unlock(&rdev->devlist_mtx);
770 	wake_up(&rdev->dev_wait);
771 
772 	dev_put(wdev->netdev);
773 }
774 
775 void cfg80211_unregister_wdev(struct wireless_dev *wdev)
776 {
777 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
778 
779 	ASSERT_RTNL();
780 
781 	if (WARN_ON(wdev->netdev))
782 		return;
783 
784 	mutex_lock(&rdev->devlist_mtx);
785 	list_del_rcu(&wdev->list);
786 	rdev->devlist_generation++;
787 
788 	switch (wdev->iftype) {
789 	case NL80211_IFTYPE_P2P_DEVICE:
790 		if (!wdev->p2p_started)
791 			break;
792 		rdev_stop_p2p_device(rdev, wdev);
793 		wdev->p2p_started = false;
794 		rdev->opencount--;
795 		break;
796 	default:
797 		WARN_ON_ONCE(1);
798 		break;
799 	}
800 	mutex_unlock(&rdev->devlist_mtx);
801 }
802 EXPORT_SYMBOL(cfg80211_unregister_wdev);
803 
804 static struct device_type wiphy_type = {
805 	.name	= "wlan",
806 };
807 
808 void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,
809 			       enum nl80211_iftype iftype, int num)
810 {
811 	ASSERT_RTNL();
812 
813 	rdev->num_running_ifaces += num;
814 	if (iftype == NL80211_IFTYPE_MONITOR)
815 		rdev->num_running_monitor_ifaces += num;
816 }
817 
818 static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
819 					 unsigned long state,
820 					 void *ndev)
821 {
822 	struct net_device *dev = ndev;
823 	struct wireless_dev *wdev = dev->ieee80211_ptr;
824 	struct cfg80211_registered_device *rdev;
825 	int ret;
826 
827 	if (!wdev)
828 		return NOTIFY_DONE;
829 
830 	rdev = wiphy_to_dev(wdev->wiphy);
831 
832 	WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
833 
834 	switch (state) {
835 	case NETDEV_POST_INIT:
836 		SET_NETDEV_DEVTYPE(dev, &wiphy_type);
837 		break;
838 	case NETDEV_REGISTER:
839 		/*
840 		 * NB: cannot take rdev->mtx here because this may be
841 		 * called within code protected by it when interfaces
842 		 * are added with nl80211.
843 		 */
844 		mutex_init(&wdev->mtx);
845 		INIT_WORK(&wdev->cleanup_work, wdev_cleanup_work);
846 		INIT_LIST_HEAD(&wdev->event_list);
847 		spin_lock_init(&wdev->event_lock);
848 		INIT_LIST_HEAD(&wdev->mgmt_registrations);
849 		spin_lock_init(&wdev->mgmt_registrations_lock);
850 
851 		mutex_lock(&rdev->devlist_mtx);
852 		wdev->identifier = ++rdev->wdev_id;
853 		list_add_rcu(&wdev->list, &rdev->wdev_list);
854 		rdev->devlist_generation++;
855 		/* can only change netns with wiphy */
856 		dev->features |= NETIF_F_NETNS_LOCAL;
857 
858 		if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
859 				      "phy80211")) {
860 			pr_err("failed to add phy80211 symlink to netdev!\n");
861 		}
862 		wdev->netdev = dev;
863 		wdev->sme_state = CFG80211_SME_IDLE;
864 		mutex_unlock(&rdev->devlist_mtx);
865 #ifdef CONFIG_CFG80211_WEXT
866 		wdev->wext.default_key = -1;
867 		wdev->wext.default_mgmt_key = -1;
868 		wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
869 #endif
870 
871 		if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
872 			wdev->ps = true;
873 		else
874 			wdev->ps = false;
875 		/* allow mac80211 to determine the timeout */
876 		wdev->ps_timeout = -1;
877 
878 		netdev_set_default_ethtool_ops(dev, &cfg80211_ethtool_ops);
879 
880 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
881 		     wdev->iftype == NL80211_IFTYPE_P2P_CLIENT ||
882 		     wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
883 			dev->priv_flags |= IFF_DONT_BRIDGE;
884 		break;
885 	case NETDEV_GOING_DOWN:
886 		switch (wdev->iftype) {
887 		case NL80211_IFTYPE_ADHOC:
888 			cfg80211_leave_ibss(rdev, dev, true);
889 			break;
890 		case NL80211_IFTYPE_P2P_CLIENT:
891 		case NL80211_IFTYPE_STATION:
892 			mutex_lock(&rdev->sched_scan_mtx);
893 			__cfg80211_stop_sched_scan(rdev, false);
894 			mutex_unlock(&rdev->sched_scan_mtx);
895 
896 			wdev_lock(wdev);
897 #ifdef CONFIG_CFG80211_WEXT
898 			kfree(wdev->wext.ie);
899 			wdev->wext.ie = NULL;
900 			wdev->wext.ie_len = 0;
901 			wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
902 #endif
903 			__cfg80211_disconnect(rdev, dev,
904 					      WLAN_REASON_DEAUTH_LEAVING, true);
905 			cfg80211_mlme_down(rdev, dev);
906 			wdev_unlock(wdev);
907 			break;
908 		case NL80211_IFTYPE_MESH_POINT:
909 			cfg80211_leave_mesh(rdev, dev);
910 			break;
911 		case NL80211_IFTYPE_AP:
912 			cfg80211_stop_ap(rdev, dev);
913 			break;
914 		default:
915 			break;
916 		}
917 		wdev->beacon_interval = 0;
918 		break;
919 	case NETDEV_DOWN:
920 		cfg80211_update_iface_num(rdev, wdev->iftype, -1);
921 		dev_hold(dev);
922 		queue_work(cfg80211_wq, &wdev->cleanup_work);
923 		break;
924 	case NETDEV_UP:
925 		/*
926 		 * If we have a really quick DOWN/UP succession we may
927 		 * have this work still pending ... cancel it and see
928 		 * if it was pending, in which case we need to account
929 		 * for some of the work it would have done.
930 		 */
931 		if (cancel_work_sync(&wdev->cleanup_work)) {
932 			mutex_lock(&rdev->devlist_mtx);
933 			rdev->opencount--;
934 			mutex_unlock(&rdev->devlist_mtx);
935 			dev_put(dev);
936 		}
937 		cfg80211_update_iface_num(rdev, wdev->iftype, 1);
938 		cfg80211_lock_rdev(rdev);
939 		mutex_lock(&rdev->devlist_mtx);
940 		wdev_lock(wdev);
941 		switch (wdev->iftype) {
942 #ifdef CONFIG_CFG80211_WEXT
943 		case NL80211_IFTYPE_ADHOC:
944 			cfg80211_ibss_wext_join(rdev, wdev);
945 			break;
946 		case NL80211_IFTYPE_STATION:
947 			cfg80211_mgd_wext_connect(rdev, wdev);
948 			break;
949 #endif
950 #ifdef CONFIG_MAC80211_MESH
951 		case NL80211_IFTYPE_MESH_POINT:
952 			{
953 				/* backward compat code... */
954 				struct mesh_setup setup;
955 				memcpy(&setup, &default_mesh_setup,
956 						sizeof(setup));
957 				 /* back compat only needed for mesh_id */
958 				setup.mesh_id = wdev->ssid;
959 				setup.mesh_id_len = wdev->mesh_id_up_len;
960 				if (wdev->mesh_id_up_len)
961 					__cfg80211_join_mesh(rdev, dev,
962 							&setup,
963 							&default_mesh_config);
964 				break;
965 			}
966 #endif
967 		default:
968 			break;
969 		}
970 		wdev_unlock(wdev);
971 		rdev->opencount++;
972 		mutex_unlock(&rdev->devlist_mtx);
973 		cfg80211_unlock_rdev(rdev);
974 
975 		/*
976 		 * Configure power management to the driver here so that its
977 		 * correctly set also after interface type changes etc.
978 		 */
979 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
980 		     wdev->iftype == NL80211_IFTYPE_P2P_CLIENT) &&
981 		    rdev->ops->set_power_mgmt)
982 			if (rdev_set_power_mgmt(rdev, dev, wdev->ps,
983 						wdev->ps_timeout)) {
984 				/* assume this means it's off */
985 				wdev->ps = false;
986 			}
987 		break;
988 	case NETDEV_UNREGISTER:
989 		/*
990 		 * NB: cannot take rdev->mtx here because this may be
991 		 * called within code protected by it when interfaces
992 		 * are removed with nl80211.
993 		 */
994 		mutex_lock(&rdev->devlist_mtx);
995 		/*
996 		 * It is possible to get NETDEV_UNREGISTER
997 		 * multiple times. To detect that, check
998 		 * that the interface is still on the list
999 		 * of registered interfaces, and only then
1000 		 * remove and clean it up.
1001 		 */
1002 		if (!list_empty(&wdev->list)) {
1003 			sysfs_remove_link(&dev->dev.kobj, "phy80211");
1004 			list_del_rcu(&wdev->list);
1005 			rdev->devlist_generation++;
1006 			cfg80211_mlme_purge_registrations(wdev);
1007 #ifdef CONFIG_CFG80211_WEXT
1008 			kfree(wdev->wext.keys);
1009 #endif
1010 		}
1011 		mutex_unlock(&rdev->devlist_mtx);
1012 		/*
1013 		 * synchronise (so that we won't find this netdev
1014 		 * from other code any more) and then clear the list
1015 		 * head so that the above code can safely check for
1016 		 * !list_empty() to avoid double-cleanup.
1017 		 */
1018 		synchronize_rcu();
1019 		INIT_LIST_HEAD(&wdev->list);
1020 		/*
1021 		 * Ensure that all events have been processed and
1022 		 * freed.
1023 		 */
1024 		cfg80211_process_wdev_events(wdev);
1025 		break;
1026 	case NETDEV_PRE_UP:
1027 		if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
1028 			return notifier_from_errno(-EOPNOTSUPP);
1029 		if (rfkill_blocked(rdev->rfkill))
1030 			return notifier_from_errno(-ERFKILL);
1031 		mutex_lock(&rdev->devlist_mtx);
1032 		ret = cfg80211_can_add_interface(rdev, wdev->iftype);
1033 		mutex_unlock(&rdev->devlist_mtx);
1034 		if (ret)
1035 			return notifier_from_errno(ret);
1036 		break;
1037 	}
1038 
1039 	return NOTIFY_DONE;
1040 }
1041 
1042 static struct notifier_block cfg80211_netdev_notifier = {
1043 	.notifier_call = cfg80211_netdev_notifier_call,
1044 };
1045 
1046 static void __net_exit cfg80211_pernet_exit(struct net *net)
1047 {
1048 	struct cfg80211_registered_device *rdev;
1049 
1050 	rtnl_lock();
1051 	mutex_lock(&cfg80211_mutex);
1052 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1053 		if (net_eq(wiphy_net(&rdev->wiphy), net))
1054 			WARN_ON(cfg80211_switch_netns(rdev, &init_net));
1055 	}
1056 	mutex_unlock(&cfg80211_mutex);
1057 	rtnl_unlock();
1058 }
1059 
1060 static struct pernet_operations cfg80211_pernet_ops = {
1061 	.exit = cfg80211_pernet_exit,
1062 };
1063 
1064 static int __init cfg80211_init(void)
1065 {
1066 	int err;
1067 
1068 	err = register_pernet_device(&cfg80211_pernet_ops);
1069 	if (err)
1070 		goto out_fail_pernet;
1071 
1072 	err = wiphy_sysfs_init();
1073 	if (err)
1074 		goto out_fail_sysfs;
1075 
1076 	err = register_netdevice_notifier(&cfg80211_netdev_notifier);
1077 	if (err)
1078 		goto out_fail_notifier;
1079 
1080 	err = nl80211_init();
1081 	if (err)
1082 		goto out_fail_nl80211;
1083 
1084 	ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
1085 
1086 	err = regulatory_init();
1087 	if (err)
1088 		goto out_fail_reg;
1089 
1090 	cfg80211_wq = create_singlethread_workqueue("cfg80211");
1091 	if (!cfg80211_wq)
1092 		goto out_fail_wq;
1093 
1094 	return 0;
1095 
1096 out_fail_wq:
1097 	regulatory_exit();
1098 out_fail_reg:
1099 	debugfs_remove(ieee80211_debugfs_dir);
1100 out_fail_nl80211:
1101 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1102 out_fail_notifier:
1103 	wiphy_sysfs_exit();
1104 out_fail_sysfs:
1105 	unregister_pernet_device(&cfg80211_pernet_ops);
1106 out_fail_pernet:
1107 	return err;
1108 }
1109 subsys_initcall(cfg80211_init);
1110 
1111 static void __exit cfg80211_exit(void)
1112 {
1113 	debugfs_remove(ieee80211_debugfs_dir);
1114 	nl80211_exit();
1115 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1116 	wiphy_sysfs_exit();
1117 	regulatory_exit();
1118 	unregister_pernet_device(&cfg80211_pernet_ops);
1119 	destroy_workqueue(cfg80211_wq);
1120 }
1121 module_exit(cfg80211_exit);
1122