xref: /openbmc/linux/net/wireless/core.c (revision 97da55fc)
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 
372 	return &rdev->wiphy;
373 }
374 EXPORT_SYMBOL(wiphy_new);
375 
376 static int wiphy_verify_combinations(struct wiphy *wiphy)
377 {
378 	const struct ieee80211_iface_combination *c;
379 	int i, j;
380 
381 	for (i = 0; i < wiphy->n_iface_combinations; i++) {
382 		u32 cnt = 0;
383 		u16 all_iftypes = 0;
384 
385 		c = &wiphy->iface_combinations[i];
386 
387 		/*
388 		 * Combinations with just one interface aren't real,
389 		 * however we make an exception for DFS.
390 		 */
391 		if (WARN_ON((c->max_interfaces < 2) && !c->radar_detect_widths))
392 			return -EINVAL;
393 
394 		/* Need at least one channel */
395 		if (WARN_ON(!c->num_different_channels))
396 			return -EINVAL;
397 
398 		/*
399 		 * Put a sane limit on maximum number of different
400 		 * channels to simplify channel accounting code.
401 		 */
402 		if (WARN_ON(c->num_different_channels >
403 				CFG80211_MAX_NUM_DIFFERENT_CHANNELS))
404 			return -EINVAL;
405 
406 		/* DFS only works on one channel. */
407 		if (WARN_ON(c->radar_detect_widths &&
408 			    (c->num_different_channels > 1)))
409 			return -EINVAL;
410 
411 		if (WARN_ON(!c->n_limits))
412 			return -EINVAL;
413 
414 		for (j = 0; j < c->n_limits; j++) {
415 			u16 types = c->limits[j].types;
416 
417 			/*
418 			 * interface types shouldn't overlap, this is
419 			 * used in cfg80211_can_change_interface()
420 			 */
421 			if (WARN_ON(types & all_iftypes))
422 				return -EINVAL;
423 			all_iftypes |= types;
424 
425 			if (WARN_ON(!c->limits[j].max))
426 				return -EINVAL;
427 
428 			/* Shouldn't list software iftypes in combinations! */
429 			if (WARN_ON(wiphy->software_iftypes & types))
430 				return -EINVAL;
431 
432 			/* Only a single P2P_DEVICE can be allowed */
433 			if (WARN_ON(types & BIT(NL80211_IFTYPE_P2P_DEVICE) &&
434 				    c->limits[j].max > 1))
435 				return -EINVAL;
436 
437 			cnt += c->limits[j].max;
438 			/*
439 			 * Don't advertise an unsupported type
440 			 * in a combination.
441 			 */
442 			if (WARN_ON((wiphy->interface_modes & types) != types))
443 				return -EINVAL;
444 		}
445 
446 		/* You can't even choose that many! */
447 		if (WARN_ON(cnt < c->max_interfaces))
448 			return -EINVAL;
449 	}
450 
451 	return 0;
452 }
453 
454 int wiphy_register(struct wiphy *wiphy)
455 {
456 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
457 	int res;
458 	enum ieee80211_band band;
459 	struct ieee80211_supported_band *sband;
460 	bool have_band = false;
461 	int i;
462 	u16 ifmodes = wiphy->interface_modes;
463 
464 #ifdef CONFIG_PM
465 	if (WARN_ON((wiphy->wowlan.flags & WIPHY_WOWLAN_GTK_REKEY_FAILURE) &&
466 		    !(wiphy->wowlan.flags & WIPHY_WOWLAN_SUPPORTS_GTK_REKEY)))
467 		return -EINVAL;
468 #endif
469 
470 	if (WARN_ON(wiphy->ap_sme_capa &&
471 		    !(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME)))
472 		return -EINVAL;
473 
474 	if (WARN_ON(wiphy->addresses && !wiphy->n_addresses))
475 		return -EINVAL;
476 
477 	if (WARN_ON(wiphy->addresses &&
478 		    !is_zero_ether_addr(wiphy->perm_addr) &&
479 		    memcmp(wiphy->perm_addr, wiphy->addresses[0].addr,
480 			   ETH_ALEN)))
481 		return -EINVAL;
482 
483 	if (WARN_ON(wiphy->max_acl_mac_addrs &&
484 		    (!(wiphy->flags & WIPHY_FLAG_HAVE_AP_SME) ||
485 		     !rdev->ops->set_mac_acl)))
486 		return -EINVAL;
487 
488 	if (wiphy->addresses)
489 		memcpy(wiphy->perm_addr, wiphy->addresses[0].addr, ETH_ALEN);
490 
491 	/* sanity check ifmodes */
492 	WARN_ON(!ifmodes);
493 	ifmodes &= ((1 << NUM_NL80211_IFTYPES) - 1) & ~1;
494 	if (WARN_ON(ifmodes != wiphy->interface_modes))
495 		wiphy->interface_modes = ifmodes;
496 
497 	res = wiphy_verify_combinations(wiphy);
498 	if (res)
499 		return res;
500 
501 	/* sanity check supported bands/channels */
502 	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
503 		sband = wiphy->bands[band];
504 		if (!sband)
505 			continue;
506 
507 		sband->band = band;
508 		if (WARN_ON(!sband->n_channels))
509 			return -EINVAL;
510 		/*
511 		 * on 60gHz band, there are no legacy rates, so
512 		 * n_bitrates is 0
513 		 */
514 		if (WARN_ON(band != IEEE80211_BAND_60GHZ &&
515 			    !sband->n_bitrates))
516 			return -EINVAL;
517 
518 		/*
519 		 * Since cfg80211_disable_40mhz_24ghz is global, we can
520 		 * modify the sband's ht data even if the driver uses a
521 		 * global structure for that.
522 		 */
523 		if (cfg80211_disable_40mhz_24ghz &&
524 		    band == IEEE80211_BAND_2GHZ &&
525 		    sband->ht_cap.ht_supported) {
526 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
527 			sband->ht_cap.cap &= ~IEEE80211_HT_CAP_SGI_40;
528 		}
529 
530 		/*
531 		 * Since we use a u32 for rate bitmaps in
532 		 * ieee80211_get_response_rate, we cannot
533 		 * have more than 32 legacy rates.
534 		 */
535 		if (WARN_ON(sband->n_bitrates > 32))
536 			return -EINVAL;
537 
538 		for (i = 0; i < sband->n_channels; i++) {
539 			sband->channels[i].orig_flags =
540 				sband->channels[i].flags;
541 			sband->channels[i].orig_mag = INT_MAX;
542 			sband->channels[i].orig_mpwr =
543 				sband->channels[i].max_power;
544 			sband->channels[i].band = band;
545 		}
546 
547 		have_band = true;
548 	}
549 
550 	if (!have_band) {
551 		WARN_ON(1);
552 		return -EINVAL;
553 	}
554 
555 #ifdef CONFIG_PM
556 	if (rdev->wiphy.wowlan.n_patterns) {
557 		if (WARN_ON(!rdev->wiphy.wowlan.pattern_min_len ||
558 			    rdev->wiphy.wowlan.pattern_min_len >
559 			    rdev->wiphy.wowlan.pattern_max_len))
560 			return -EINVAL;
561 	}
562 #endif
563 
564 	/* check and set up bitrates */
565 	ieee80211_set_bitrate_flags(wiphy);
566 
567 	mutex_lock(&cfg80211_mutex);
568 
569 	res = device_add(&rdev->wiphy.dev);
570 	if (res) {
571 		mutex_unlock(&cfg80211_mutex);
572 		return res;
573 	}
574 
575 	/* set up regulatory info */
576 	wiphy_regulatory_register(wiphy);
577 
578 	list_add_rcu(&rdev->list, &cfg80211_rdev_list);
579 	cfg80211_rdev_list_generation++;
580 
581 	/* add to debugfs */
582 	rdev->wiphy.debugfsdir =
583 		debugfs_create_dir(wiphy_name(&rdev->wiphy),
584 				   ieee80211_debugfs_dir);
585 	if (IS_ERR(rdev->wiphy.debugfsdir))
586 		rdev->wiphy.debugfsdir = NULL;
587 
588 	if (wiphy->flags & WIPHY_FLAG_CUSTOM_REGULATORY) {
589 		struct regulatory_request request;
590 
591 		request.wiphy_idx = get_wiphy_idx(wiphy);
592 		request.initiator = NL80211_REGDOM_SET_BY_DRIVER;
593 		request.alpha2[0] = '9';
594 		request.alpha2[1] = '9';
595 
596 		nl80211_send_reg_change_event(&request);
597 	}
598 
599 	cfg80211_debugfs_rdev_add(rdev);
600 	mutex_unlock(&cfg80211_mutex);
601 
602 	/*
603 	 * due to a locking dependency this has to be outside of the
604 	 * cfg80211_mutex lock
605 	 */
606 	res = rfkill_register(rdev->rfkill);
607 	if (res)
608 		goto out_rm_dev;
609 
610 	rtnl_lock();
611 	rdev->wiphy.registered = true;
612 	rtnl_unlock();
613 	return 0;
614 
615 out_rm_dev:
616 	device_del(&rdev->wiphy.dev);
617 	return res;
618 }
619 EXPORT_SYMBOL(wiphy_register);
620 
621 void wiphy_rfkill_start_polling(struct wiphy *wiphy)
622 {
623 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
624 
625 	if (!rdev->ops->rfkill_poll)
626 		return;
627 	rdev->rfkill_ops.poll = cfg80211_rfkill_poll;
628 	rfkill_resume_polling(rdev->rfkill);
629 }
630 EXPORT_SYMBOL(wiphy_rfkill_start_polling);
631 
632 void wiphy_rfkill_stop_polling(struct wiphy *wiphy)
633 {
634 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
635 
636 	rfkill_pause_polling(rdev->rfkill);
637 }
638 EXPORT_SYMBOL(wiphy_rfkill_stop_polling);
639 
640 void wiphy_unregister(struct wiphy *wiphy)
641 {
642 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
643 
644 	rtnl_lock();
645 	rdev->wiphy.registered = false;
646 	rtnl_unlock();
647 
648 	rfkill_unregister(rdev->rfkill);
649 
650 	/* protect the device list */
651 	mutex_lock(&cfg80211_mutex);
652 
653 	wait_event(rdev->dev_wait, ({
654 		int __count;
655 		mutex_lock(&rdev->devlist_mtx);
656 		__count = rdev->opencount;
657 		mutex_unlock(&rdev->devlist_mtx);
658 		__count == 0; }));
659 
660 	mutex_lock(&rdev->devlist_mtx);
661 	BUG_ON(!list_empty(&rdev->wdev_list));
662 	mutex_unlock(&rdev->devlist_mtx);
663 
664 	/*
665 	 * First remove the hardware from everywhere, this makes
666 	 * it impossible to find from userspace.
667 	 */
668 	debugfs_remove_recursive(rdev->wiphy.debugfsdir);
669 	list_del_rcu(&rdev->list);
670 	synchronize_rcu();
671 
672 	/*
673 	 * Try to grab rdev->mtx. If a command is still in progress,
674 	 * hopefully the driver will refuse it since it's tearing
675 	 * down the device already. We wait for this command to complete
676 	 * before unlinking the item from the list.
677 	 * Note: as codified by the BUG_ON above we cannot get here if
678 	 * a virtual interface is still present. Hence, we can only get
679 	 * to lock contention here if userspace issues a command that
680 	 * identified the hardware by wiphy index.
681 	 */
682 	cfg80211_lock_rdev(rdev);
683 	/* nothing */
684 	cfg80211_unlock_rdev(rdev);
685 
686 	/*
687 	 * If this device got a regulatory hint tell core its
688 	 * free to listen now to a new shiny device regulatory hint
689 	 */
690 	wiphy_regulatory_deregister(wiphy);
691 
692 	cfg80211_rdev_list_generation++;
693 	device_del(&rdev->wiphy.dev);
694 
695 	mutex_unlock(&cfg80211_mutex);
696 
697 	flush_work(&rdev->scan_done_wk);
698 	cancel_work_sync(&rdev->conn_work);
699 	flush_work(&rdev->event_work);
700 	cancel_delayed_work_sync(&rdev->dfs_update_channels_wk);
701 
702 	if (rdev->wowlan && rdev->ops->set_wakeup)
703 		rdev_set_wakeup(rdev, false);
704 	cfg80211_rdev_free_wowlan(rdev);
705 }
706 EXPORT_SYMBOL(wiphy_unregister);
707 
708 void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
709 {
710 	struct cfg80211_internal_bss *scan, *tmp;
711 	struct cfg80211_beacon_registration *reg, *treg;
712 	rfkill_destroy(rdev->rfkill);
713 	mutex_destroy(&rdev->mtx);
714 	mutex_destroy(&rdev->devlist_mtx);
715 	mutex_destroy(&rdev->sched_scan_mtx);
716 	list_for_each_entry_safe(reg, treg, &rdev->beacon_registrations, list) {
717 		list_del(&reg->list);
718 		kfree(reg);
719 	}
720 	list_for_each_entry_safe(scan, tmp, &rdev->bss_list, list)
721 		cfg80211_put_bss(&rdev->wiphy, &scan->pub);
722 	kfree(rdev);
723 }
724 
725 void wiphy_free(struct wiphy *wiphy)
726 {
727 	put_device(&wiphy->dev);
728 }
729 EXPORT_SYMBOL(wiphy_free);
730 
731 void wiphy_rfkill_set_hw_state(struct wiphy *wiphy, bool blocked)
732 {
733 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wiphy);
734 
735 	if (rfkill_set_hw_state(rdev->rfkill, blocked))
736 		schedule_work(&rdev->rfkill_sync);
737 }
738 EXPORT_SYMBOL(wiphy_rfkill_set_hw_state);
739 
740 static void wdev_cleanup_work(struct work_struct *work)
741 {
742 	struct wireless_dev *wdev;
743 	struct cfg80211_registered_device *rdev;
744 
745 	wdev = container_of(work, struct wireless_dev, cleanup_work);
746 	rdev = wiphy_to_dev(wdev->wiphy);
747 
748 	cfg80211_lock_rdev(rdev);
749 
750 	if (WARN_ON(rdev->scan_req && rdev->scan_req->wdev == wdev)) {
751 		rdev->scan_req->aborted = true;
752 		___cfg80211_scan_done(rdev, true);
753 	}
754 
755 	cfg80211_unlock_rdev(rdev);
756 
757 	mutex_lock(&rdev->sched_scan_mtx);
758 
759 	if (WARN_ON(rdev->sched_scan_req &&
760 		    rdev->sched_scan_req->dev == wdev->netdev)) {
761 		__cfg80211_stop_sched_scan(rdev, false);
762 	}
763 
764 	mutex_unlock(&rdev->sched_scan_mtx);
765 
766 	mutex_lock(&rdev->devlist_mtx);
767 	rdev->opencount--;
768 	mutex_unlock(&rdev->devlist_mtx);
769 	wake_up(&rdev->dev_wait);
770 
771 	dev_put(wdev->netdev);
772 }
773 
774 void cfg80211_unregister_wdev(struct wireless_dev *wdev)
775 {
776 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
777 
778 	ASSERT_RTNL();
779 
780 	if (WARN_ON(wdev->netdev))
781 		return;
782 
783 	mutex_lock(&rdev->devlist_mtx);
784 	list_del_rcu(&wdev->list);
785 	rdev->devlist_generation++;
786 
787 	switch (wdev->iftype) {
788 	case NL80211_IFTYPE_P2P_DEVICE:
789 		if (!wdev->p2p_started)
790 			break;
791 		rdev_stop_p2p_device(rdev, wdev);
792 		wdev->p2p_started = false;
793 		rdev->opencount--;
794 		break;
795 	default:
796 		WARN_ON_ONCE(1);
797 		break;
798 	}
799 	mutex_unlock(&rdev->devlist_mtx);
800 }
801 EXPORT_SYMBOL(cfg80211_unregister_wdev);
802 
803 static struct device_type wiphy_type = {
804 	.name	= "wlan",
805 };
806 
807 void cfg80211_update_iface_num(struct cfg80211_registered_device *rdev,
808 			       enum nl80211_iftype iftype, int num)
809 {
810 	ASSERT_RTNL();
811 
812 	rdev->num_running_ifaces += num;
813 	if (iftype == NL80211_IFTYPE_MONITOR)
814 		rdev->num_running_monitor_ifaces += num;
815 }
816 
817 static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
818 					 unsigned long state,
819 					 void *ndev)
820 {
821 	struct net_device *dev = ndev;
822 	struct wireless_dev *wdev = dev->ieee80211_ptr;
823 	struct cfg80211_registered_device *rdev;
824 	int ret;
825 
826 	if (!wdev)
827 		return NOTIFY_DONE;
828 
829 	rdev = wiphy_to_dev(wdev->wiphy);
830 
831 	WARN_ON(wdev->iftype == NL80211_IFTYPE_UNSPECIFIED);
832 
833 	switch (state) {
834 	case NETDEV_POST_INIT:
835 		SET_NETDEV_DEVTYPE(dev, &wiphy_type);
836 		break;
837 	case NETDEV_REGISTER:
838 		/*
839 		 * NB: cannot take rdev->mtx here because this may be
840 		 * called within code protected by it when interfaces
841 		 * are added with nl80211.
842 		 */
843 		mutex_init(&wdev->mtx);
844 		INIT_WORK(&wdev->cleanup_work, wdev_cleanup_work);
845 		INIT_LIST_HEAD(&wdev->event_list);
846 		spin_lock_init(&wdev->event_lock);
847 		INIT_LIST_HEAD(&wdev->mgmt_registrations);
848 		spin_lock_init(&wdev->mgmt_registrations_lock);
849 
850 		mutex_lock(&rdev->devlist_mtx);
851 		wdev->identifier = ++rdev->wdev_id;
852 		list_add_rcu(&wdev->list, &rdev->wdev_list);
853 		rdev->devlist_generation++;
854 		/* can only change netns with wiphy */
855 		dev->features |= NETIF_F_NETNS_LOCAL;
856 
857 		if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
858 				      "phy80211")) {
859 			pr_err("failed to add phy80211 symlink to netdev!\n");
860 		}
861 		wdev->netdev = dev;
862 		wdev->sme_state = CFG80211_SME_IDLE;
863 		mutex_unlock(&rdev->devlist_mtx);
864 #ifdef CONFIG_CFG80211_WEXT
865 		wdev->wext.default_key = -1;
866 		wdev->wext.default_mgmt_key = -1;
867 		wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
868 #endif
869 
870 		if (wdev->wiphy->flags & WIPHY_FLAG_PS_ON_BY_DEFAULT)
871 			wdev->ps = true;
872 		else
873 			wdev->ps = false;
874 		/* allow mac80211 to determine the timeout */
875 		wdev->ps_timeout = -1;
876 
877 		netdev_set_default_ethtool_ops(dev, &cfg80211_ethtool_ops);
878 
879 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
880 		     wdev->iftype == NL80211_IFTYPE_P2P_CLIENT ||
881 		     wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr)
882 			dev->priv_flags |= IFF_DONT_BRIDGE;
883 		break;
884 	case NETDEV_GOING_DOWN:
885 		switch (wdev->iftype) {
886 		case NL80211_IFTYPE_ADHOC:
887 			cfg80211_leave_ibss(rdev, dev, true);
888 			break;
889 		case NL80211_IFTYPE_P2P_CLIENT:
890 		case NL80211_IFTYPE_STATION:
891 			mutex_lock(&rdev->sched_scan_mtx);
892 			__cfg80211_stop_sched_scan(rdev, false);
893 			mutex_unlock(&rdev->sched_scan_mtx);
894 
895 			wdev_lock(wdev);
896 #ifdef CONFIG_CFG80211_WEXT
897 			kfree(wdev->wext.ie);
898 			wdev->wext.ie = NULL;
899 			wdev->wext.ie_len = 0;
900 			wdev->wext.connect.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
901 #endif
902 			__cfg80211_disconnect(rdev, dev,
903 					      WLAN_REASON_DEAUTH_LEAVING, true);
904 			cfg80211_mlme_down(rdev, dev);
905 			wdev_unlock(wdev);
906 			break;
907 		case NL80211_IFTYPE_MESH_POINT:
908 			cfg80211_leave_mesh(rdev, dev);
909 			break;
910 		case NL80211_IFTYPE_AP:
911 			cfg80211_stop_ap(rdev, dev);
912 			break;
913 		default:
914 			break;
915 		}
916 		wdev->beacon_interval = 0;
917 		break;
918 	case NETDEV_DOWN:
919 		cfg80211_update_iface_num(rdev, wdev->iftype, -1);
920 		dev_hold(dev);
921 		queue_work(cfg80211_wq, &wdev->cleanup_work);
922 		break;
923 	case NETDEV_UP:
924 		/*
925 		 * If we have a really quick DOWN/UP succession we may
926 		 * have this work still pending ... cancel it and see
927 		 * if it was pending, in which case we need to account
928 		 * for some of the work it would have done.
929 		 */
930 		if (cancel_work_sync(&wdev->cleanup_work)) {
931 			mutex_lock(&rdev->devlist_mtx);
932 			rdev->opencount--;
933 			mutex_unlock(&rdev->devlist_mtx);
934 			dev_put(dev);
935 		}
936 		cfg80211_update_iface_num(rdev, wdev->iftype, 1);
937 		cfg80211_lock_rdev(rdev);
938 		mutex_lock(&rdev->devlist_mtx);
939 		wdev_lock(wdev);
940 		switch (wdev->iftype) {
941 #ifdef CONFIG_CFG80211_WEXT
942 		case NL80211_IFTYPE_ADHOC:
943 			cfg80211_ibss_wext_join(rdev, wdev);
944 			break;
945 		case NL80211_IFTYPE_STATION:
946 			cfg80211_mgd_wext_connect(rdev, wdev);
947 			break;
948 #endif
949 #ifdef CONFIG_MAC80211_MESH
950 		case NL80211_IFTYPE_MESH_POINT:
951 			{
952 				/* backward compat code... */
953 				struct mesh_setup setup;
954 				memcpy(&setup, &default_mesh_setup,
955 						sizeof(setup));
956 				 /* back compat only needed for mesh_id */
957 				setup.mesh_id = wdev->ssid;
958 				setup.mesh_id_len = wdev->mesh_id_up_len;
959 				if (wdev->mesh_id_up_len)
960 					__cfg80211_join_mesh(rdev, dev,
961 							&setup,
962 							&default_mesh_config);
963 				break;
964 			}
965 #endif
966 		default:
967 			break;
968 		}
969 		wdev_unlock(wdev);
970 		rdev->opencount++;
971 		mutex_unlock(&rdev->devlist_mtx);
972 		cfg80211_unlock_rdev(rdev);
973 
974 		/*
975 		 * Configure power management to the driver here so that its
976 		 * correctly set also after interface type changes etc.
977 		 */
978 		if ((wdev->iftype == NL80211_IFTYPE_STATION ||
979 		     wdev->iftype == NL80211_IFTYPE_P2P_CLIENT) &&
980 		    rdev->ops->set_power_mgmt)
981 			if (rdev_set_power_mgmt(rdev, dev, wdev->ps,
982 						wdev->ps_timeout)) {
983 				/* assume this means it's off */
984 				wdev->ps = false;
985 			}
986 		break;
987 	case NETDEV_UNREGISTER:
988 		/*
989 		 * NB: cannot take rdev->mtx here because this may be
990 		 * called within code protected by it when interfaces
991 		 * are removed with nl80211.
992 		 */
993 		mutex_lock(&rdev->devlist_mtx);
994 		/*
995 		 * It is possible to get NETDEV_UNREGISTER
996 		 * multiple times. To detect that, check
997 		 * that the interface is still on the list
998 		 * of registered interfaces, and only then
999 		 * remove and clean it up.
1000 		 */
1001 		if (!list_empty(&wdev->list)) {
1002 			sysfs_remove_link(&dev->dev.kobj, "phy80211");
1003 			list_del_rcu(&wdev->list);
1004 			rdev->devlist_generation++;
1005 			cfg80211_mlme_purge_registrations(wdev);
1006 #ifdef CONFIG_CFG80211_WEXT
1007 			kfree(wdev->wext.keys);
1008 #endif
1009 		}
1010 		mutex_unlock(&rdev->devlist_mtx);
1011 		/*
1012 		 * synchronise (so that we won't find this netdev
1013 		 * from other code any more) and then clear the list
1014 		 * head so that the above code can safely check for
1015 		 * !list_empty() to avoid double-cleanup.
1016 		 */
1017 		synchronize_rcu();
1018 		INIT_LIST_HEAD(&wdev->list);
1019 		/*
1020 		 * Ensure that all events have been processed and
1021 		 * freed.
1022 		 */
1023 		cfg80211_process_wdev_events(wdev);
1024 		break;
1025 	case NETDEV_PRE_UP:
1026 		if (!(wdev->wiphy->interface_modes & BIT(wdev->iftype)))
1027 			return notifier_from_errno(-EOPNOTSUPP);
1028 		if (rfkill_blocked(rdev->rfkill))
1029 			return notifier_from_errno(-ERFKILL);
1030 		mutex_lock(&rdev->devlist_mtx);
1031 		ret = cfg80211_can_add_interface(rdev, wdev->iftype);
1032 		mutex_unlock(&rdev->devlist_mtx);
1033 		if (ret)
1034 			return notifier_from_errno(ret);
1035 		break;
1036 	}
1037 
1038 	return NOTIFY_DONE;
1039 }
1040 
1041 static struct notifier_block cfg80211_netdev_notifier = {
1042 	.notifier_call = cfg80211_netdev_notifier_call,
1043 };
1044 
1045 static void __net_exit cfg80211_pernet_exit(struct net *net)
1046 {
1047 	struct cfg80211_registered_device *rdev;
1048 
1049 	rtnl_lock();
1050 	mutex_lock(&cfg80211_mutex);
1051 	list_for_each_entry(rdev, &cfg80211_rdev_list, list) {
1052 		if (net_eq(wiphy_net(&rdev->wiphy), net))
1053 			WARN_ON(cfg80211_switch_netns(rdev, &init_net));
1054 	}
1055 	mutex_unlock(&cfg80211_mutex);
1056 	rtnl_unlock();
1057 }
1058 
1059 static struct pernet_operations cfg80211_pernet_ops = {
1060 	.exit = cfg80211_pernet_exit,
1061 };
1062 
1063 static int __init cfg80211_init(void)
1064 {
1065 	int err;
1066 
1067 	err = register_pernet_device(&cfg80211_pernet_ops);
1068 	if (err)
1069 		goto out_fail_pernet;
1070 
1071 	err = wiphy_sysfs_init();
1072 	if (err)
1073 		goto out_fail_sysfs;
1074 
1075 	err = register_netdevice_notifier(&cfg80211_netdev_notifier);
1076 	if (err)
1077 		goto out_fail_notifier;
1078 
1079 	err = nl80211_init();
1080 	if (err)
1081 		goto out_fail_nl80211;
1082 
1083 	ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
1084 
1085 	err = regulatory_init();
1086 	if (err)
1087 		goto out_fail_reg;
1088 
1089 	cfg80211_wq = create_singlethread_workqueue("cfg80211");
1090 	if (!cfg80211_wq)
1091 		goto out_fail_wq;
1092 
1093 	return 0;
1094 
1095 out_fail_wq:
1096 	regulatory_exit();
1097 out_fail_reg:
1098 	debugfs_remove(ieee80211_debugfs_dir);
1099 out_fail_nl80211:
1100 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1101 out_fail_notifier:
1102 	wiphy_sysfs_exit();
1103 out_fail_sysfs:
1104 	unregister_pernet_device(&cfg80211_pernet_ops);
1105 out_fail_pernet:
1106 	return err;
1107 }
1108 subsys_initcall(cfg80211_init);
1109 
1110 static void __exit cfg80211_exit(void)
1111 {
1112 	debugfs_remove(ieee80211_debugfs_dir);
1113 	nl80211_exit();
1114 	unregister_netdevice_notifier(&cfg80211_netdev_notifier);
1115 	wiphy_sysfs_exit();
1116 	regulatory_exit();
1117 	unregister_pernet_device(&cfg80211_pernet_ops);
1118 	destroy_workqueue(cfg80211_wq);
1119 }
1120 module_exit(cfg80211_exit);
1121