xref: /openbmc/linux/net/mac80211/iface.c (revision 55de908ab292c03f1eb280f51170ddb9c6b57e31)
1 /*
2  * Interface handling (except master interface)
3  *
4  * Copyright 2002-2005, Instant802 Networks, Inc.
5  * Copyright 2005-2006, Devicescape Software, Inc.
6  * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
7  * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 #include <linux/slab.h>
14 #include <linux/kernel.h>
15 #include <linux/if_arp.h>
16 #include <linux/netdevice.h>
17 #include <linux/rtnetlink.h>
18 #include <net/mac80211.h>
19 #include <net/ieee80211_radiotap.h>
20 #include "ieee80211_i.h"
21 #include "sta_info.h"
22 #include "debugfs_netdev.h"
23 #include "mesh.h"
24 #include "led.h"
25 #include "driver-ops.h"
26 #include "wme.h"
27 #include "rate.h"
28 
29 /**
30  * DOC: Interface list locking
31  *
32  * The interface list in each struct ieee80211_local is protected
33  * three-fold:
34  *
35  * (1) modifications may only be done under the RTNL
36  * (2) modifications and readers are protected against each other by
37  *     the iflist_mtx.
38  * (3) modifications are done in an RCU manner so atomic readers
39  *     can traverse the list in RCU-safe blocks.
40  *
41  * As a consequence, reads (traversals) of the list can be protected
42  * by either the RTNL, the iflist_mtx or RCU.
43  */
44 
45 
46 static u32 ieee80211_idle_off(struct ieee80211_local *local,
47 			      const char *reason)
48 {
49 	if (!(local->hw.conf.flags & IEEE80211_CONF_IDLE))
50 		return 0;
51 
52 	local->hw.conf.flags &= ~IEEE80211_CONF_IDLE;
53 	return IEEE80211_CONF_CHANGE_IDLE;
54 }
55 
56 static u32 ieee80211_idle_on(struct ieee80211_local *local)
57 {
58 	if (local->hw.conf.flags & IEEE80211_CONF_IDLE)
59 		return 0;
60 
61 	drv_flush(local, false);
62 
63 	local->hw.conf.flags |= IEEE80211_CONF_IDLE;
64 	return IEEE80211_CONF_CHANGE_IDLE;
65 }
66 
67 static u32 __ieee80211_recalc_idle(struct ieee80211_local *local)
68 {
69 	struct ieee80211_sub_if_data *sdata;
70 	int count = 0;
71 	bool working = false, scanning = false;
72 	unsigned int led_trig_start = 0, led_trig_stop = 0;
73 	struct ieee80211_roc_work *roc;
74 
75 #ifdef CONFIG_PROVE_LOCKING
76 	WARN_ON(debug_locks && !lockdep_rtnl_is_held() &&
77 		!lockdep_is_held(&local->iflist_mtx));
78 #endif
79 	lockdep_assert_held(&local->mtx);
80 
81 	list_for_each_entry(sdata, &local->interfaces, list) {
82 		if (!ieee80211_sdata_running(sdata)) {
83 			sdata->vif.bss_conf.idle = true;
84 			continue;
85 		}
86 
87 		sdata->old_idle = sdata->vif.bss_conf.idle;
88 
89 		/* do not count disabled managed interfaces */
90 		if (sdata->vif.type == NL80211_IFTYPE_STATION &&
91 		    !sdata->u.mgd.associated &&
92 		    !sdata->u.mgd.auth_data &&
93 		    !sdata->u.mgd.assoc_data) {
94 			sdata->vif.bss_conf.idle = true;
95 			continue;
96 		}
97 		/* do not count unused IBSS interfaces */
98 		if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
99 		    !sdata->u.ibss.ssid_len) {
100 			sdata->vif.bss_conf.idle = true;
101 			continue;
102 		}
103 
104 		if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE)
105 			continue;
106 
107 		/* count everything else */
108 		sdata->vif.bss_conf.idle = false;
109 		count++;
110 	}
111 
112 	if (!local->ops->remain_on_channel) {
113 		list_for_each_entry(roc, &local->roc_list, list) {
114 			working = true;
115 			roc->sdata->vif.bss_conf.idle = false;
116 		}
117 	}
118 
119 	sdata = rcu_dereference_protected(local->scan_sdata,
120 					  lockdep_is_held(&local->mtx));
121 	if (sdata && !(local->hw.flags & IEEE80211_HW_SCAN_WHILE_IDLE)) {
122 		scanning = true;
123 		sdata->vif.bss_conf.idle = false;
124 	}
125 
126 	list_for_each_entry(sdata, &local->interfaces, list) {
127 		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
128 		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
129 		    sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE)
130 			continue;
131 		if (sdata->old_idle == sdata->vif.bss_conf.idle)
132 			continue;
133 		if (!ieee80211_sdata_running(sdata))
134 			continue;
135 		ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IDLE);
136 	}
137 
138 	if (working || scanning)
139 		led_trig_start |= IEEE80211_TPT_LEDTRIG_FL_WORK;
140 	else
141 		led_trig_stop |= IEEE80211_TPT_LEDTRIG_FL_WORK;
142 
143 	if (count)
144 		led_trig_start |= IEEE80211_TPT_LEDTRIG_FL_CONNECTED;
145 	else
146 		led_trig_stop |= IEEE80211_TPT_LEDTRIG_FL_CONNECTED;
147 
148 	ieee80211_mod_tpt_led_trig(local, led_trig_start, led_trig_stop);
149 
150 	if (working)
151 		return ieee80211_idle_off(local, "working");
152 	if (scanning)
153 		return ieee80211_idle_off(local, "scanning");
154 	if (!count)
155 		return ieee80211_idle_on(local);
156 	else
157 		return ieee80211_idle_off(local, "in use");
158 
159 	return 0;
160 }
161 
162 void ieee80211_recalc_idle(struct ieee80211_local *local)
163 {
164 	u32 chg;
165 
166 	mutex_lock(&local->iflist_mtx);
167 	chg = __ieee80211_recalc_idle(local);
168 	mutex_unlock(&local->iflist_mtx);
169 	if (chg)
170 		ieee80211_hw_config(local, chg);
171 }
172 
173 static int ieee80211_change_mtu(struct net_device *dev, int new_mtu)
174 {
175 	int meshhdrlen;
176 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
177 
178 	meshhdrlen = (sdata->vif.type == NL80211_IFTYPE_MESH_POINT) ? 5 : 0;
179 
180 	/* FIX: what would be proper limits for MTU?
181 	 * This interface uses 802.3 frames. */
182 	if (new_mtu < 256 ||
183 	    new_mtu > IEEE80211_MAX_DATA_LEN - 24 - 6 - meshhdrlen) {
184 		return -EINVAL;
185 	}
186 
187 	dev->mtu = new_mtu;
188 	return 0;
189 }
190 
191 static int ieee80211_change_mac(struct net_device *dev, void *addr)
192 {
193 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
194 	struct sockaddr *sa = addr;
195 	int ret;
196 
197 	if (ieee80211_sdata_running(sdata))
198 		return -EBUSY;
199 
200 	ret = eth_mac_addr(dev, sa);
201 
202 	if (ret == 0)
203 		memcpy(sdata->vif.addr, sa->sa_data, ETH_ALEN);
204 
205 	return ret;
206 }
207 
208 static inline int identical_mac_addr_allowed(int type1, int type2)
209 {
210 	return type1 == NL80211_IFTYPE_MONITOR ||
211 		type2 == NL80211_IFTYPE_MONITOR ||
212 		type1 == NL80211_IFTYPE_P2P_DEVICE ||
213 		type2 == NL80211_IFTYPE_P2P_DEVICE ||
214 		(type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_WDS) ||
215 		(type1 == NL80211_IFTYPE_WDS &&
216 			(type2 == NL80211_IFTYPE_WDS ||
217 			 type2 == NL80211_IFTYPE_AP)) ||
218 		(type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_AP_VLAN) ||
219 		(type1 == NL80211_IFTYPE_AP_VLAN &&
220 			(type2 == NL80211_IFTYPE_AP ||
221 			 type2 == NL80211_IFTYPE_AP_VLAN));
222 }
223 
224 static int ieee80211_check_concurrent_iface(struct ieee80211_sub_if_data *sdata,
225 					    enum nl80211_iftype iftype)
226 {
227 	struct ieee80211_local *local = sdata->local;
228 	struct ieee80211_sub_if_data *nsdata;
229 
230 	ASSERT_RTNL();
231 
232 	/* we hold the RTNL here so can safely walk the list */
233 	list_for_each_entry(nsdata, &local->interfaces, list) {
234 		if (nsdata != sdata && ieee80211_sdata_running(nsdata)) {
235 			/*
236 			 * Allow only a single IBSS interface to be up at any
237 			 * time. This is restricted because beacon distribution
238 			 * cannot work properly if both are in the same IBSS.
239 			 *
240 			 * To remove this restriction we'd have to disallow them
241 			 * from setting the same SSID on different IBSS interfaces
242 			 * belonging to the same hardware. Then, however, we're
243 			 * faced with having to adopt two different TSF timers...
244 			 */
245 			if (iftype == NL80211_IFTYPE_ADHOC &&
246 			    nsdata->vif.type == NL80211_IFTYPE_ADHOC)
247 				return -EBUSY;
248 
249 			/*
250 			 * The remaining checks are only performed for interfaces
251 			 * with the same MAC address.
252 			 */
253 			if (!ether_addr_equal(sdata->vif.addr,
254 					      nsdata->vif.addr))
255 				continue;
256 
257 			/*
258 			 * check whether it may have the same address
259 			 */
260 			if (!identical_mac_addr_allowed(iftype,
261 							nsdata->vif.type))
262 				return -ENOTUNIQ;
263 
264 			/*
265 			 * can only add VLANs to enabled APs
266 			 */
267 			if (iftype == NL80211_IFTYPE_AP_VLAN &&
268 			    nsdata->vif.type == NL80211_IFTYPE_AP)
269 				sdata->bss = &nsdata->u.ap;
270 		}
271 	}
272 
273 	return 0;
274 }
275 
276 static int ieee80211_check_queues(struct ieee80211_sub_if_data *sdata)
277 {
278 	int n_queues = sdata->local->hw.queues;
279 	int i;
280 
281 	if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE) {
282 		for (i = 0; i < IEEE80211_NUM_ACS; i++) {
283 			if (WARN_ON_ONCE(sdata->vif.hw_queue[i] ==
284 					 IEEE80211_INVAL_HW_QUEUE))
285 				return -EINVAL;
286 			if (WARN_ON_ONCE(sdata->vif.hw_queue[i] >=
287 					 n_queues))
288 				return -EINVAL;
289 		}
290 	}
291 
292 	if ((sdata->vif.type != NL80211_IFTYPE_AP) ||
293 	    !(sdata->local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)) {
294 		sdata->vif.cab_queue = IEEE80211_INVAL_HW_QUEUE;
295 		return 0;
296 	}
297 
298 	if (WARN_ON_ONCE(sdata->vif.cab_queue == IEEE80211_INVAL_HW_QUEUE))
299 		return -EINVAL;
300 
301 	if (WARN_ON_ONCE(sdata->vif.cab_queue >= n_queues))
302 		return -EINVAL;
303 
304 	return 0;
305 }
306 
307 void ieee80211_adjust_monitor_flags(struct ieee80211_sub_if_data *sdata,
308 				    const int offset)
309 {
310 	struct ieee80211_local *local = sdata->local;
311 	u32 flags = sdata->u.mntr_flags;
312 
313 #define ADJUST(_f, _s)	do {					\
314 	if (flags & MONITOR_FLAG_##_f)				\
315 		local->fif_##_s += offset;			\
316 	} while (0)
317 
318 	ADJUST(FCSFAIL, fcsfail);
319 	ADJUST(PLCPFAIL, plcpfail);
320 	ADJUST(CONTROL, control);
321 	ADJUST(CONTROL, pspoll);
322 	ADJUST(OTHER_BSS, other_bss);
323 
324 #undef ADJUST
325 }
326 
327 static void ieee80211_set_default_queues(struct ieee80211_sub_if_data *sdata)
328 {
329 	struct ieee80211_local *local = sdata->local;
330 	int i;
331 
332 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
333 		if (local->hw.flags & IEEE80211_HW_QUEUE_CONTROL)
334 			sdata->vif.hw_queue[i] = IEEE80211_INVAL_HW_QUEUE;
335 		else if (local->hw.queues >= IEEE80211_NUM_ACS)
336 			sdata->vif.hw_queue[i] = i;
337 		else
338 			sdata->vif.hw_queue[i] = 0;
339 	}
340 	sdata->vif.cab_queue = IEEE80211_INVAL_HW_QUEUE;
341 }
342 
343 static int ieee80211_add_virtual_monitor(struct ieee80211_local *local)
344 {
345 	struct ieee80211_sub_if_data *sdata;
346 	int ret = 0;
347 
348 	if (!(local->hw.flags & IEEE80211_HW_WANT_MONITOR_VIF))
349 		return 0;
350 
351 	mutex_lock(&local->iflist_mtx);
352 
353 	if (local->monitor_sdata)
354 		goto out_unlock;
355 
356 	sdata = kzalloc(sizeof(*sdata) + local->hw.vif_data_size, GFP_KERNEL);
357 	if (!sdata) {
358 		ret = -ENOMEM;
359 		goto out_unlock;
360 	}
361 
362 	/* set up data */
363 	sdata->local = local;
364 	sdata->vif.type = NL80211_IFTYPE_MONITOR;
365 	snprintf(sdata->name, IFNAMSIZ, "%s-monitor",
366 		 wiphy_name(local->hw.wiphy));
367 
368 	ieee80211_set_default_queues(sdata);
369 
370 	ret = drv_add_interface(local, sdata);
371 	if (WARN_ON(ret)) {
372 		/* ok .. stupid driver, it asked for this! */
373 		kfree(sdata);
374 		goto out_unlock;
375 	}
376 
377 	ret = ieee80211_check_queues(sdata);
378 	if (ret) {
379 		kfree(sdata);
380 		goto out_unlock;
381 	}
382 
383 	ret = ieee80211_vif_use_channel(sdata, local->monitor_channel,
384 					local->monitor_channel_type,
385 					IEEE80211_CHANCTX_EXCLUSIVE);
386 	if (ret) {
387 		drv_remove_interface(local, sdata);
388 		kfree(sdata);
389 		goto out_unlock;
390 	}
391 
392 	rcu_assign_pointer(local->monitor_sdata, sdata);
393  out_unlock:
394 	mutex_unlock(&local->iflist_mtx);
395 	return ret;
396 }
397 
398 static void ieee80211_del_virtual_monitor(struct ieee80211_local *local)
399 {
400 	struct ieee80211_sub_if_data *sdata;
401 
402 	if (!(local->hw.flags & IEEE80211_HW_WANT_MONITOR_VIF))
403 		return;
404 
405 	mutex_lock(&local->iflist_mtx);
406 
407 	sdata = rcu_dereference_protected(local->monitor_sdata,
408 					  lockdep_is_held(&local->iflist_mtx));
409 	if (!sdata)
410 		goto out_unlock;
411 
412 	rcu_assign_pointer(local->monitor_sdata, NULL);
413 	synchronize_net();
414 
415 	ieee80211_vif_release_channel(sdata);
416 
417 	drv_remove_interface(local, sdata);
418 
419 	kfree(sdata);
420  out_unlock:
421 	mutex_unlock(&local->iflist_mtx);
422 }
423 
424 /*
425  * NOTE: Be very careful when changing this function, it must NOT return
426  * an error on interface type changes that have been pre-checked, so most
427  * checks should be in ieee80211_check_concurrent_iface.
428  */
429 int ieee80211_do_open(struct wireless_dev *wdev, bool coming_up)
430 {
431 	struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
432 	struct net_device *dev = wdev->netdev;
433 	struct ieee80211_local *local = sdata->local;
434 	struct sta_info *sta;
435 	u32 changed = 0;
436 	int res;
437 	u32 hw_reconf_flags = 0;
438 
439 	switch (sdata->vif.type) {
440 	case NL80211_IFTYPE_WDS:
441 		if (!is_valid_ether_addr(sdata->u.wds.remote_addr))
442 			return -ENOLINK;
443 		break;
444 	case NL80211_IFTYPE_AP_VLAN: {
445 		struct ieee80211_sub_if_data *master;
446 
447 		if (!sdata->bss)
448 			return -ENOLINK;
449 
450 		list_add(&sdata->u.vlan.list, &sdata->bss->vlans);
451 
452 		master = container_of(sdata->bss,
453 				      struct ieee80211_sub_if_data, u.ap);
454 		sdata->control_port_protocol =
455 			master->control_port_protocol;
456 		sdata->control_port_no_encrypt =
457 			master->control_port_no_encrypt;
458 		break;
459 		}
460 	case NL80211_IFTYPE_AP:
461 		sdata->bss = &sdata->u.ap;
462 		break;
463 	case NL80211_IFTYPE_MESH_POINT:
464 	case NL80211_IFTYPE_STATION:
465 	case NL80211_IFTYPE_MONITOR:
466 	case NL80211_IFTYPE_ADHOC:
467 	case NL80211_IFTYPE_P2P_DEVICE:
468 		/* no special treatment */
469 		break;
470 	case NL80211_IFTYPE_UNSPECIFIED:
471 	case NUM_NL80211_IFTYPES:
472 	case NL80211_IFTYPE_P2P_CLIENT:
473 	case NL80211_IFTYPE_P2P_GO:
474 		/* cannot happen */
475 		WARN_ON(1);
476 		break;
477 	}
478 
479 	if (local->open_count == 0) {
480 		res = drv_start(local);
481 		if (res)
482 			goto err_del_bss;
483 		if (local->ops->napi_poll)
484 			napi_enable(&local->napi);
485 		/* we're brought up, everything changes */
486 		hw_reconf_flags = ~0;
487 		ieee80211_led_radio(local, true);
488 		ieee80211_mod_tpt_led_trig(local,
489 					   IEEE80211_TPT_LEDTRIG_FL_RADIO, 0);
490 	}
491 
492 	/*
493 	 * Copy the hopefully now-present MAC address to
494 	 * this interface, if it has the special null one.
495 	 */
496 	if (dev && is_zero_ether_addr(dev->dev_addr)) {
497 		memcpy(dev->dev_addr,
498 		       local->hw.wiphy->perm_addr,
499 		       ETH_ALEN);
500 		memcpy(dev->perm_addr, dev->dev_addr, ETH_ALEN);
501 
502 		if (!is_valid_ether_addr(dev->dev_addr)) {
503 			res = -EADDRNOTAVAIL;
504 			goto err_stop;
505 		}
506 	}
507 
508 	switch (sdata->vif.type) {
509 	case NL80211_IFTYPE_AP_VLAN:
510 		/* no need to tell driver, but set carrier */
511 		if (rtnl_dereference(sdata->bss->beacon))
512 			netif_carrier_on(dev);
513 		else
514 			netif_carrier_off(dev);
515 		break;
516 	case NL80211_IFTYPE_MONITOR:
517 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
518 			local->cooked_mntrs++;
519 			break;
520 		}
521 
522 		if (local->monitors == 0 && local->open_count == 0) {
523 			res = ieee80211_add_virtual_monitor(local);
524 			if (res)
525 				goto err_stop;
526 		}
527 
528 		/* must be before the call to ieee80211_configure_filter */
529 		local->monitors++;
530 		if (local->monitors == 1) {
531 			local->hw.conf.flags |= IEEE80211_CONF_MONITOR;
532 			hw_reconf_flags |= IEEE80211_CONF_CHANGE_MONITOR;
533 		}
534 
535 		ieee80211_adjust_monitor_flags(sdata, 1);
536 		ieee80211_configure_filter(local);
537 
538 		netif_carrier_on(dev);
539 		break;
540 	default:
541 		if (coming_up) {
542 			ieee80211_del_virtual_monitor(local);
543 
544 			res = drv_add_interface(local, sdata);
545 			if (res)
546 				goto err_stop;
547 			res = ieee80211_check_queues(sdata);
548 			if (res)
549 				goto err_del_interface;
550 		}
551 
552 		if (sdata->vif.type == NL80211_IFTYPE_AP) {
553 			local->fif_pspoll++;
554 			local->fif_probe_req++;
555 
556 			ieee80211_configure_filter(local);
557 		} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
558 			local->fif_probe_req++;
559 		}
560 
561 		if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE)
562 			changed |= ieee80211_reset_erp_info(sdata);
563 		ieee80211_bss_info_change_notify(sdata, changed);
564 
565 		switch (sdata->vif.type) {
566 		case NL80211_IFTYPE_STATION:
567 		case NL80211_IFTYPE_ADHOC:
568 		case NL80211_IFTYPE_AP:
569 		case NL80211_IFTYPE_MESH_POINT:
570 			netif_carrier_off(dev);
571 			break;
572 		case NL80211_IFTYPE_WDS:
573 		case NL80211_IFTYPE_P2P_DEVICE:
574 			break;
575 		default:
576 			netif_carrier_on(dev);
577 		}
578 
579 		/*
580 		 * set default queue parameters so drivers don't
581 		 * need to initialise the hardware if the hardware
582 		 * doesn't start up with sane defaults
583 		 */
584 		ieee80211_set_wmm_default(sdata, true);
585 	}
586 
587 	set_bit(SDATA_STATE_RUNNING, &sdata->state);
588 
589 	if (sdata->vif.type == NL80211_IFTYPE_WDS) {
590 		/* Create STA entry for the WDS peer */
591 		sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
592 				     GFP_KERNEL);
593 		if (!sta) {
594 			res = -ENOMEM;
595 			goto err_del_interface;
596 		}
597 
598 		sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
599 		sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
600 		sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
601 
602 		res = sta_info_insert(sta);
603 		if (res) {
604 			/* STA has been freed */
605 			goto err_del_interface;
606 		}
607 
608 		rate_control_rate_init(sta);
609 		netif_carrier_on(dev);
610 	} else if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE) {
611 		rcu_assign_pointer(local->p2p_sdata, sdata);
612 	}
613 
614 	/*
615 	 * set_multicast_list will be invoked by the networking core
616 	 * which will check whether any increments here were done in
617 	 * error and sync them down to the hardware as filter flags.
618 	 */
619 	if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
620 		atomic_inc(&local->iff_allmultis);
621 
622 	if (sdata->flags & IEEE80211_SDATA_PROMISC)
623 		atomic_inc(&local->iff_promiscs);
624 
625 	mutex_lock(&local->mtx);
626 	hw_reconf_flags |= __ieee80211_recalc_idle(local);
627 	mutex_unlock(&local->mtx);
628 
629 	if (coming_up)
630 		local->open_count++;
631 
632 	if (hw_reconf_flags)
633 		ieee80211_hw_config(local, hw_reconf_flags);
634 
635 	ieee80211_recalc_ps(local, -1);
636 
637 	if (dev)
638 		netif_tx_start_all_queues(dev);
639 
640 	return 0;
641  err_del_interface:
642 	drv_remove_interface(local, sdata);
643  err_stop:
644 	if (!local->open_count)
645 		drv_stop(local);
646  err_del_bss:
647 	sdata->bss = NULL;
648 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
649 		list_del(&sdata->u.vlan.list);
650 	/* might already be clear but that doesn't matter */
651 	clear_bit(SDATA_STATE_RUNNING, &sdata->state);
652 	return res;
653 }
654 
655 static int ieee80211_open(struct net_device *dev)
656 {
657 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
658 	int err;
659 
660 	/* fail early if user set an invalid address */
661 	if (!is_valid_ether_addr(dev->dev_addr))
662 		return -EADDRNOTAVAIL;
663 
664 	err = ieee80211_check_concurrent_iface(sdata, sdata->vif.type);
665 	if (err)
666 		return err;
667 
668 	return ieee80211_do_open(&sdata->wdev, true);
669 }
670 
671 static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
672 			      bool going_down)
673 {
674 	struct ieee80211_local *local = sdata->local;
675 	unsigned long flags;
676 	struct sk_buff *skb, *tmp;
677 	u32 hw_reconf_flags = 0;
678 	int i;
679 
680 	clear_bit(SDATA_STATE_RUNNING, &sdata->state);
681 
682 	if (rcu_access_pointer(local->scan_sdata) == sdata)
683 		ieee80211_scan_cancel(local);
684 
685 	/*
686 	 * Stop TX on this interface first.
687 	 */
688 	if (sdata->dev)
689 		netif_tx_stop_all_queues(sdata->dev);
690 
691 	ieee80211_roc_purge(sdata);
692 
693 	/*
694 	 * Remove all stations associated with this interface.
695 	 *
696 	 * This must be done before calling ops->remove_interface()
697 	 * because otherwise we can later invoke ops->sta_notify()
698 	 * whenever the STAs are removed, and that invalidates driver
699 	 * assumptions about always getting a vif pointer that is valid
700 	 * (because if we remove a STA after ops->remove_interface()
701 	 * the driver will have removed the vif info already!)
702 	 *
703 	 * This is relevant only in AP, WDS and mesh modes, since in
704 	 * all other modes we've already removed all stations when
705 	 * disconnecting etc.
706 	 */
707 	sta_info_flush(local, sdata);
708 
709 	/*
710 	 * Don't count this interface for promisc/allmulti while it
711 	 * is down. dev_mc_unsync() will invoke set_multicast_list
712 	 * on the master interface which will sync these down to the
713 	 * hardware as filter flags.
714 	 */
715 	if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
716 		atomic_dec(&local->iff_allmultis);
717 
718 	if (sdata->flags & IEEE80211_SDATA_PROMISC)
719 		atomic_dec(&local->iff_promiscs);
720 
721 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
722 		local->fif_pspoll--;
723 		local->fif_probe_req--;
724 	} else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
725 		local->fif_probe_req--;
726 	}
727 
728 	if (sdata->dev) {
729 		netif_addr_lock_bh(sdata->dev);
730 		spin_lock_bh(&local->filter_lock);
731 		__hw_addr_unsync(&local->mc_list, &sdata->dev->mc,
732 				 sdata->dev->addr_len);
733 		spin_unlock_bh(&local->filter_lock);
734 		netif_addr_unlock_bh(sdata->dev);
735 
736 		ieee80211_configure_filter(local);
737 	}
738 
739 	del_timer_sync(&local->dynamic_ps_timer);
740 	cancel_work_sync(&local->dynamic_ps_enable_work);
741 
742 	/* APs need special treatment */
743 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
744 		struct ieee80211_sub_if_data *vlan, *tmpsdata;
745 		struct beacon_data *old_beacon =
746 			rtnl_dereference(sdata->u.ap.beacon);
747 		struct probe_resp *old_probe_resp =
748 			rtnl_dereference(sdata->u.ap.probe_resp);
749 
750 		/* sdata_running will return false, so this will disable */
751 		ieee80211_bss_info_change_notify(sdata,
752 						 BSS_CHANGED_BEACON_ENABLED);
753 
754 		/* remove beacon and probe response */
755 		RCU_INIT_POINTER(sdata->u.ap.beacon, NULL);
756 		RCU_INIT_POINTER(sdata->u.ap.probe_resp, NULL);
757 		synchronize_rcu();
758 		kfree(old_beacon);
759 		kfree(old_probe_resp);
760 
761 		/* down all dependent devices, that is VLANs */
762 		list_for_each_entry_safe(vlan, tmpsdata, &sdata->u.ap.vlans,
763 					 u.vlan.list)
764 			dev_close(vlan->dev);
765 		WARN_ON(!list_empty(&sdata->u.ap.vlans));
766 
767 		/* free all potentially still buffered bcast frames */
768 		local->total_ps_buffered -= skb_queue_len(&sdata->u.ap.ps_bc_buf);
769 		skb_queue_purge(&sdata->u.ap.ps_bc_buf);
770 	} else if (sdata->vif.type == NL80211_IFTYPE_STATION) {
771 		ieee80211_mgd_stop(sdata);
772 	}
773 
774 	if (going_down)
775 		local->open_count--;
776 
777 	switch (sdata->vif.type) {
778 	case NL80211_IFTYPE_AP_VLAN:
779 		list_del(&sdata->u.vlan.list);
780 		/* no need to tell driver */
781 		break;
782 	case NL80211_IFTYPE_MONITOR:
783 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
784 			local->cooked_mntrs--;
785 			break;
786 		}
787 
788 		local->monitors--;
789 		if (local->monitors == 0) {
790 			local->hw.conf.flags &= ~IEEE80211_CONF_MONITOR;
791 			hw_reconf_flags |= IEEE80211_CONF_CHANGE_MONITOR;
792 			ieee80211_del_virtual_monitor(local);
793 		}
794 
795 		ieee80211_adjust_monitor_flags(sdata, -1);
796 		ieee80211_configure_filter(local);
797 		break;
798 	case NL80211_IFTYPE_P2P_DEVICE:
799 		/* relies on synchronize_rcu() below */
800 		rcu_assign_pointer(local->p2p_sdata, NULL);
801 		/* fall through */
802 	default:
803 		flush_work(&sdata->work);
804 		/*
805 		 * When we get here, the interface is marked down.
806 		 * Call rcu_barrier() to wait both for the RX path
807 		 * should it be using the interface and enqueuing
808 		 * frames at this very time on another CPU, and
809 		 * for the sta free call_rcu callbacks.
810 		 */
811 		rcu_barrier();
812 
813 		/*
814 		 * free_sta_rcu() enqueues a work for the actual
815 		 * sta cleanup, so we need to flush it while
816 		 * sdata is still valid.
817 		 */
818 		flush_workqueue(local->workqueue);
819 
820 		skb_queue_purge(&sdata->skb_queue);
821 
822 		/*
823 		 * Free all remaining keys, there shouldn't be any,
824 		 * except maybe group keys in AP more or WDS?
825 		 */
826 		ieee80211_free_keys(sdata);
827 
828 		if (going_down)
829 			drv_remove_interface(local, sdata);
830 	}
831 
832 	sdata->bss = NULL;
833 
834 	mutex_lock(&local->mtx);
835 	hw_reconf_flags |= __ieee80211_recalc_idle(local);
836 	mutex_unlock(&local->mtx);
837 
838 	ieee80211_recalc_ps(local, -1);
839 
840 	if (local->open_count == 0) {
841 		if (local->ops->napi_poll)
842 			napi_disable(&local->napi);
843 		ieee80211_clear_tx_pending(local);
844 		ieee80211_stop_device(local);
845 
846 		/* no reconfiguring after stop! */
847 		hw_reconf_flags = 0;
848 	}
849 
850 	/* do after stop to avoid reconfiguring when we stop anyway */
851 	if (hw_reconf_flags)
852 		ieee80211_hw_config(local, hw_reconf_flags);
853 
854 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
855 	for (i = 0; i < IEEE80211_MAX_QUEUES; i++) {
856 		skb_queue_walk_safe(&local->pending[i], skb, tmp) {
857 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
858 			if (info->control.vif == &sdata->vif) {
859 				__skb_unlink(skb, &local->pending[i]);
860 				dev_kfree_skb_irq(skb);
861 			}
862 		}
863 	}
864 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
865 
866 	if (local->monitors == local->open_count && local->monitors > 0)
867 		ieee80211_add_virtual_monitor(local);
868 }
869 
870 static int ieee80211_stop(struct net_device *dev)
871 {
872 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
873 
874 	ieee80211_do_stop(sdata, true);
875 
876 	return 0;
877 }
878 
879 static void ieee80211_set_multicast_list(struct net_device *dev)
880 {
881 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
882 	struct ieee80211_local *local = sdata->local;
883 	int allmulti, promisc, sdata_allmulti, sdata_promisc;
884 
885 	allmulti = !!(dev->flags & IFF_ALLMULTI);
886 	promisc = !!(dev->flags & IFF_PROMISC);
887 	sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
888 	sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
889 
890 	if (allmulti != sdata_allmulti) {
891 		if (dev->flags & IFF_ALLMULTI)
892 			atomic_inc(&local->iff_allmultis);
893 		else
894 			atomic_dec(&local->iff_allmultis);
895 		sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
896 	}
897 
898 	if (promisc != sdata_promisc) {
899 		if (dev->flags & IFF_PROMISC)
900 			atomic_inc(&local->iff_promiscs);
901 		else
902 			atomic_dec(&local->iff_promiscs);
903 		sdata->flags ^= IEEE80211_SDATA_PROMISC;
904 	}
905 	spin_lock_bh(&local->filter_lock);
906 	__hw_addr_sync(&local->mc_list, &dev->mc, dev->addr_len);
907 	spin_unlock_bh(&local->filter_lock);
908 	ieee80211_queue_work(&local->hw, &local->reconfig_filter);
909 }
910 
911 /*
912  * Called when the netdev is removed or, by the code below, before
913  * the interface type changes.
914  */
915 static void ieee80211_teardown_sdata(struct ieee80211_sub_if_data *sdata)
916 {
917 	struct ieee80211_local *local = sdata->local;
918 	int flushed;
919 	int i;
920 
921 	/* free extra data */
922 	ieee80211_free_keys(sdata);
923 
924 	ieee80211_debugfs_remove_netdev(sdata);
925 
926 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
927 		__skb_queue_purge(&sdata->fragments[i].skb_list);
928 	sdata->fragment_next = 0;
929 
930 	if (ieee80211_vif_is_mesh(&sdata->vif))
931 		mesh_rmc_free(sdata);
932 
933 	flushed = sta_info_flush(local, sdata);
934 	WARN_ON(flushed);
935 }
936 
937 static void ieee80211_uninit(struct net_device *dev)
938 {
939 	ieee80211_teardown_sdata(IEEE80211_DEV_TO_SUB_IF(dev));
940 }
941 
942 static u16 ieee80211_netdev_select_queue(struct net_device *dev,
943 					 struct sk_buff *skb)
944 {
945 	return ieee80211_select_queue(IEEE80211_DEV_TO_SUB_IF(dev), skb);
946 }
947 
948 static const struct net_device_ops ieee80211_dataif_ops = {
949 	.ndo_open		= ieee80211_open,
950 	.ndo_stop		= ieee80211_stop,
951 	.ndo_uninit		= ieee80211_uninit,
952 	.ndo_start_xmit		= ieee80211_subif_start_xmit,
953 	.ndo_set_rx_mode	= ieee80211_set_multicast_list,
954 	.ndo_change_mtu 	= ieee80211_change_mtu,
955 	.ndo_set_mac_address 	= ieee80211_change_mac,
956 	.ndo_select_queue	= ieee80211_netdev_select_queue,
957 };
958 
959 static u16 ieee80211_monitor_select_queue(struct net_device *dev,
960 					  struct sk_buff *skb)
961 {
962 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
963 	struct ieee80211_local *local = sdata->local;
964 	struct ieee80211_hdr *hdr;
965 	struct ieee80211_radiotap_header *rtap = (void *)skb->data;
966 
967 	if (local->hw.queues < IEEE80211_NUM_ACS)
968 		return 0;
969 
970 	if (skb->len < 4 ||
971 	    skb->len < le16_to_cpu(rtap->it_len) + 2 /* frame control */)
972 		return 0; /* doesn't matter, frame will be dropped */
973 
974 	hdr = (void *)((u8 *)skb->data + le16_to_cpu(rtap->it_len));
975 
976 	return ieee80211_select_queue_80211(sdata, skb, hdr);
977 }
978 
979 static const struct net_device_ops ieee80211_monitorif_ops = {
980 	.ndo_open		= ieee80211_open,
981 	.ndo_stop		= ieee80211_stop,
982 	.ndo_uninit		= ieee80211_uninit,
983 	.ndo_start_xmit		= ieee80211_monitor_start_xmit,
984 	.ndo_set_rx_mode	= ieee80211_set_multicast_list,
985 	.ndo_change_mtu 	= ieee80211_change_mtu,
986 	.ndo_set_mac_address 	= eth_mac_addr,
987 	.ndo_select_queue	= ieee80211_monitor_select_queue,
988 };
989 
990 static void ieee80211_if_setup(struct net_device *dev)
991 {
992 	ether_setup(dev);
993 	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
994 	dev->netdev_ops = &ieee80211_dataif_ops;
995 	dev->destructor = free_netdev;
996 }
997 
998 static void ieee80211_iface_work(struct work_struct *work)
999 {
1000 	struct ieee80211_sub_if_data *sdata =
1001 		container_of(work, struct ieee80211_sub_if_data, work);
1002 	struct ieee80211_local *local = sdata->local;
1003 	struct sk_buff *skb;
1004 	struct sta_info *sta;
1005 	struct ieee80211_ra_tid *ra_tid;
1006 
1007 	if (!ieee80211_sdata_running(sdata))
1008 		return;
1009 
1010 	if (local->scanning)
1011 		return;
1012 
1013 	/*
1014 	 * ieee80211_queue_work() should have picked up most cases,
1015 	 * here we'll pick the rest.
1016 	 */
1017 	if (WARN(local->suspended,
1018 		 "interface work scheduled while going to suspend\n"))
1019 		return;
1020 
1021 	/* first process frames */
1022 	while ((skb = skb_dequeue(&sdata->skb_queue))) {
1023 		struct ieee80211_mgmt *mgmt = (void *)skb->data;
1024 
1025 		if (skb->pkt_type == IEEE80211_SDATA_QUEUE_AGG_START) {
1026 			ra_tid = (void *)&skb->cb;
1027 			ieee80211_start_tx_ba_cb(&sdata->vif, ra_tid->ra,
1028 						 ra_tid->tid);
1029 		} else if (skb->pkt_type == IEEE80211_SDATA_QUEUE_AGG_STOP) {
1030 			ra_tid = (void *)&skb->cb;
1031 			ieee80211_stop_tx_ba_cb(&sdata->vif, ra_tid->ra,
1032 						ra_tid->tid);
1033 		} else if (ieee80211_is_action(mgmt->frame_control) &&
1034 			   mgmt->u.action.category == WLAN_CATEGORY_BACK) {
1035 			int len = skb->len;
1036 
1037 			mutex_lock(&local->sta_mtx);
1038 			sta = sta_info_get_bss(sdata, mgmt->sa);
1039 			if (sta) {
1040 				switch (mgmt->u.action.u.addba_req.action_code) {
1041 				case WLAN_ACTION_ADDBA_REQ:
1042 					ieee80211_process_addba_request(
1043 							local, sta, mgmt, len);
1044 					break;
1045 				case WLAN_ACTION_ADDBA_RESP:
1046 					ieee80211_process_addba_resp(local, sta,
1047 								     mgmt, len);
1048 					break;
1049 				case WLAN_ACTION_DELBA:
1050 					ieee80211_process_delba(sdata, sta,
1051 								mgmt, len);
1052 					break;
1053 				default:
1054 					WARN_ON(1);
1055 					break;
1056 				}
1057 			}
1058 			mutex_unlock(&local->sta_mtx);
1059 		} else if (ieee80211_is_data_qos(mgmt->frame_control)) {
1060 			struct ieee80211_hdr *hdr = (void *)mgmt;
1061 			/*
1062 			 * So the frame isn't mgmt, but frame_control
1063 			 * is at the right place anyway, of course, so
1064 			 * the if statement is correct.
1065 			 *
1066 			 * Warn if we have other data frame types here,
1067 			 * they must not get here.
1068 			 */
1069 			WARN_ON(hdr->frame_control &
1070 					cpu_to_le16(IEEE80211_STYPE_NULLFUNC));
1071 			WARN_ON(!(hdr->seq_ctrl &
1072 					cpu_to_le16(IEEE80211_SCTL_FRAG)));
1073 			/*
1074 			 * This was a fragment of a frame, received while
1075 			 * a block-ack session was active. That cannot be
1076 			 * right, so terminate the session.
1077 			 */
1078 			mutex_lock(&local->sta_mtx);
1079 			sta = sta_info_get_bss(sdata, mgmt->sa);
1080 			if (sta) {
1081 				u16 tid = *ieee80211_get_qos_ctl(hdr) &
1082 						IEEE80211_QOS_CTL_TID_MASK;
1083 
1084 				__ieee80211_stop_rx_ba_session(
1085 					sta, tid, WLAN_BACK_RECIPIENT,
1086 					WLAN_REASON_QSTA_REQUIRE_SETUP,
1087 					true);
1088 			}
1089 			mutex_unlock(&local->sta_mtx);
1090 		} else switch (sdata->vif.type) {
1091 		case NL80211_IFTYPE_STATION:
1092 			ieee80211_sta_rx_queued_mgmt(sdata, skb);
1093 			break;
1094 		case NL80211_IFTYPE_ADHOC:
1095 			ieee80211_ibss_rx_queued_mgmt(sdata, skb);
1096 			break;
1097 		case NL80211_IFTYPE_MESH_POINT:
1098 			if (!ieee80211_vif_is_mesh(&sdata->vif))
1099 				break;
1100 			ieee80211_mesh_rx_queued_mgmt(sdata, skb);
1101 			break;
1102 		default:
1103 			WARN(1, "frame for unexpected interface type");
1104 			break;
1105 		}
1106 
1107 		kfree_skb(skb);
1108 	}
1109 
1110 	/* then other type-dependent work */
1111 	switch (sdata->vif.type) {
1112 	case NL80211_IFTYPE_STATION:
1113 		ieee80211_sta_work(sdata);
1114 		break;
1115 	case NL80211_IFTYPE_ADHOC:
1116 		ieee80211_ibss_work(sdata);
1117 		break;
1118 	case NL80211_IFTYPE_MESH_POINT:
1119 		if (!ieee80211_vif_is_mesh(&sdata->vif))
1120 			break;
1121 		ieee80211_mesh_work(sdata);
1122 		break;
1123 	default:
1124 		break;
1125 	}
1126 }
1127 
1128 
1129 /*
1130  * Helper function to initialise an interface to a specific type.
1131  */
1132 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
1133 				  enum nl80211_iftype type)
1134 {
1135 	/* clear type-dependent union */
1136 	memset(&sdata->u, 0, sizeof(sdata->u));
1137 
1138 	/* and set some type-dependent values */
1139 	sdata->vif.type = type;
1140 	sdata->vif.p2p = false;
1141 	sdata->wdev.iftype = type;
1142 
1143 	sdata->control_port_protocol = cpu_to_be16(ETH_P_PAE);
1144 	sdata->control_port_no_encrypt = false;
1145 
1146 	sdata->noack_map = 0;
1147 
1148 	/* only monitor/p2p-device differ */
1149 	if (sdata->dev) {
1150 		sdata->dev->netdev_ops = &ieee80211_dataif_ops;
1151 		sdata->dev->type = ARPHRD_ETHER;
1152 	}
1153 
1154 	skb_queue_head_init(&sdata->skb_queue);
1155 	INIT_WORK(&sdata->work, ieee80211_iface_work);
1156 
1157 	switch (type) {
1158 	case NL80211_IFTYPE_P2P_GO:
1159 		type = NL80211_IFTYPE_AP;
1160 		sdata->vif.type = type;
1161 		sdata->vif.p2p = true;
1162 		/* fall through */
1163 	case NL80211_IFTYPE_AP:
1164 		skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
1165 		INIT_LIST_HEAD(&sdata->u.ap.vlans);
1166 		break;
1167 	case NL80211_IFTYPE_P2P_CLIENT:
1168 		type = NL80211_IFTYPE_STATION;
1169 		sdata->vif.type = type;
1170 		sdata->vif.p2p = true;
1171 		/* fall through */
1172 	case NL80211_IFTYPE_STATION:
1173 		ieee80211_sta_setup_sdata(sdata);
1174 		break;
1175 	case NL80211_IFTYPE_ADHOC:
1176 		ieee80211_ibss_setup_sdata(sdata);
1177 		break;
1178 	case NL80211_IFTYPE_MESH_POINT:
1179 		if (ieee80211_vif_is_mesh(&sdata->vif))
1180 			ieee80211_mesh_init_sdata(sdata);
1181 		break;
1182 	case NL80211_IFTYPE_MONITOR:
1183 		sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
1184 		sdata->dev->netdev_ops = &ieee80211_monitorif_ops;
1185 		sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
1186 				      MONITOR_FLAG_OTHER_BSS;
1187 		break;
1188 	case NL80211_IFTYPE_WDS:
1189 	case NL80211_IFTYPE_AP_VLAN:
1190 	case NL80211_IFTYPE_P2P_DEVICE:
1191 		break;
1192 	case NL80211_IFTYPE_UNSPECIFIED:
1193 	case NUM_NL80211_IFTYPES:
1194 		BUG();
1195 		break;
1196 	}
1197 
1198 	ieee80211_debugfs_add_netdev(sdata);
1199 }
1200 
1201 static int ieee80211_runtime_change_iftype(struct ieee80211_sub_if_data *sdata,
1202 					   enum nl80211_iftype type)
1203 {
1204 	struct ieee80211_local *local = sdata->local;
1205 	int ret, err;
1206 	enum nl80211_iftype internal_type = type;
1207 	bool p2p = false;
1208 
1209 	ASSERT_RTNL();
1210 
1211 	if (!local->ops->change_interface)
1212 		return -EBUSY;
1213 
1214 	switch (sdata->vif.type) {
1215 	case NL80211_IFTYPE_AP:
1216 	case NL80211_IFTYPE_STATION:
1217 	case NL80211_IFTYPE_ADHOC:
1218 		/*
1219 		 * Could maybe also all others here?
1220 		 * Just not sure how that interacts
1221 		 * with the RX/config path e.g. for
1222 		 * mesh.
1223 		 */
1224 		break;
1225 	default:
1226 		return -EBUSY;
1227 	}
1228 
1229 	switch (type) {
1230 	case NL80211_IFTYPE_AP:
1231 	case NL80211_IFTYPE_STATION:
1232 	case NL80211_IFTYPE_ADHOC:
1233 		/*
1234 		 * Could probably support everything
1235 		 * but WDS here (WDS do_open can fail
1236 		 * under memory pressure, which this
1237 		 * code isn't prepared to handle).
1238 		 */
1239 		break;
1240 	case NL80211_IFTYPE_P2P_CLIENT:
1241 		p2p = true;
1242 		internal_type = NL80211_IFTYPE_STATION;
1243 		break;
1244 	case NL80211_IFTYPE_P2P_GO:
1245 		p2p = true;
1246 		internal_type = NL80211_IFTYPE_AP;
1247 		break;
1248 	default:
1249 		return -EBUSY;
1250 	}
1251 
1252 	ret = ieee80211_check_concurrent_iface(sdata, internal_type);
1253 	if (ret)
1254 		return ret;
1255 
1256 	ieee80211_do_stop(sdata, false);
1257 
1258 	ieee80211_teardown_sdata(sdata);
1259 
1260 	ret = drv_change_interface(local, sdata, internal_type, p2p);
1261 	if (ret)
1262 		type = sdata->vif.type;
1263 
1264 	/*
1265 	 * Ignore return value here, there's not much we can do since
1266 	 * the driver changed the interface type internally already.
1267 	 * The warnings will hopefully make driver authors fix it :-)
1268 	 */
1269 	ieee80211_check_queues(sdata);
1270 
1271 	ieee80211_setup_sdata(sdata, type);
1272 
1273 	err = ieee80211_do_open(&sdata->wdev, false);
1274 	WARN(err, "type change: do_open returned %d", err);
1275 
1276 	return ret;
1277 }
1278 
1279 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
1280 			     enum nl80211_iftype type)
1281 {
1282 	int ret;
1283 
1284 	ASSERT_RTNL();
1285 
1286 	if (type == ieee80211_vif_type_p2p(&sdata->vif))
1287 		return 0;
1288 
1289 	if (ieee80211_sdata_running(sdata)) {
1290 		ret = ieee80211_runtime_change_iftype(sdata, type);
1291 		if (ret)
1292 			return ret;
1293 	} else {
1294 		/* Purge and reset type-dependent state. */
1295 		ieee80211_teardown_sdata(sdata);
1296 		ieee80211_setup_sdata(sdata, type);
1297 	}
1298 
1299 	/* reset some values that shouldn't be kept across type changes */
1300 	sdata->drop_unencrypted = 0;
1301 	if (type == NL80211_IFTYPE_STATION)
1302 		sdata->u.mgd.use_4addr = false;
1303 
1304 	return 0;
1305 }
1306 
1307 static void ieee80211_assign_perm_addr(struct ieee80211_local *local,
1308 				       u8 *perm_addr, enum nl80211_iftype type)
1309 {
1310 	struct ieee80211_sub_if_data *sdata;
1311 	u64 mask, start, addr, val, inc;
1312 	u8 *m;
1313 	u8 tmp_addr[ETH_ALEN];
1314 	int i;
1315 
1316 	/* default ... something at least */
1317 	memcpy(perm_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
1318 
1319 	if (is_zero_ether_addr(local->hw.wiphy->addr_mask) &&
1320 	    local->hw.wiphy->n_addresses <= 1)
1321 		return;
1322 
1323 	mutex_lock(&local->iflist_mtx);
1324 
1325 	switch (type) {
1326 	case NL80211_IFTYPE_MONITOR:
1327 		/* doesn't matter */
1328 		break;
1329 	case NL80211_IFTYPE_WDS:
1330 	case NL80211_IFTYPE_AP_VLAN:
1331 		/* match up with an AP interface */
1332 		list_for_each_entry(sdata, &local->interfaces, list) {
1333 			if (sdata->vif.type != NL80211_IFTYPE_AP)
1334 				continue;
1335 			memcpy(perm_addr, sdata->vif.addr, ETH_ALEN);
1336 			break;
1337 		}
1338 		/* keep default if no AP interface present */
1339 		break;
1340 	case NL80211_IFTYPE_P2P_CLIENT:
1341 	case NL80211_IFTYPE_P2P_GO:
1342 		if (local->hw.flags & IEEE80211_HW_P2P_DEV_ADDR_FOR_INTF) {
1343 			list_for_each_entry(sdata, &local->interfaces, list) {
1344 				if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE)
1345 					continue;
1346 				if (!ieee80211_sdata_running(sdata))
1347 					continue;
1348 				memcpy(perm_addr, sdata->vif.addr, ETH_ALEN);
1349 				goto out_unlock;
1350 			}
1351 		}
1352 		/* otherwise fall through */
1353 	default:
1354 		/* assign a new address if possible -- try n_addresses first */
1355 		for (i = 0; i < local->hw.wiphy->n_addresses; i++) {
1356 			bool used = false;
1357 
1358 			list_for_each_entry(sdata, &local->interfaces, list) {
1359 				if (memcmp(local->hw.wiphy->addresses[i].addr,
1360 					   sdata->vif.addr, ETH_ALEN) == 0) {
1361 					used = true;
1362 					break;
1363 				}
1364 			}
1365 
1366 			if (!used) {
1367 				memcpy(perm_addr,
1368 				       local->hw.wiphy->addresses[i].addr,
1369 				       ETH_ALEN);
1370 				break;
1371 			}
1372 		}
1373 
1374 		/* try mask if available */
1375 		if (is_zero_ether_addr(local->hw.wiphy->addr_mask))
1376 			break;
1377 
1378 		m = local->hw.wiphy->addr_mask;
1379 		mask =	((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
1380 			((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
1381 			((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
1382 
1383 		if (__ffs64(mask) + hweight64(mask) != fls64(mask)) {
1384 			/* not a contiguous mask ... not handled now! */
1385 			pr_info("not contiguous\n");
1386 			break;
1387 		}
1388 
1389 		m = local->hw.wiphy->perm_addr;
1390 		start = ((u64)m[0] << 5*8) | ((u64)m[1] << 4*8) |
1391 			((u64)m[2] << 3*8) | ((u64)m[3] << 2*8) |
1392 			((u64)m[4] << 1*8) | ((u64)m[5] << 0*8);
1393 
1394 		inc = 1ULL<<__ffs64(mask);
1395 		val = (start & mask);
1396 		addr = (start & ~mask) | (val & mask);
1397 		do {
1398 			bool used = false;
1399 
1400 			tmp_addr[5] = addr >> 0*8;
1401 			tmp_addr[4] = addr >> 1*8;
1402 			tmp_addr[3] = addr >> 2*8;
1403 			tmp_addr[2] = addr >> 3*8;
1404 			tmp_addr[1] = addr >> 4*8;
1405 			tmp_addr[0] = addr >> 5*8;
1406 
1407 			val += inc;
1408 
1409 			list_for_each_entry(sdata, &local->interfaces, list) {
1410 				if (memcmp(tmp_addr, sdata->vif.addr,
1411 							ETH_ALEN) == 0) {
1412 					used = true;
1413 					break;
1414 				}
1415 			}
1416 
1417 			if (!used) {
1418 				memcpy(perm_addr, tmp_addr, ETH_ALEN);
1419 				break;
1420 			}
1421 			addr = (start & ~mask) | (val & mask);
1422 		} while (addr != start);
1423 
1424 		break;
1425 	}
1426 
1427  out_unlock:
1428 	mutex_unlock(&local->iflist_mtx);
1429 }
1430 
1431 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
1432 		     struct wireless_dev **new_wdev, enum nl80211_iftype type,
1433 		     struct vif_params *params)
1434 {
1435 	struct net_device *ndev = NULL;
1436 	struct ieee80211_sub_if_data *sdata = NULL;
1437 	int ret, i;
1438 	int txqs = 1;
1439 
1440 	ASSERT_RTNL();
1441 
1442 	if (type == NL80211_IFTYPE_P2P_DEVICE) {
1443 		struct wireless_dev *wdev;
1444 
1445 		sdata = kzalloc(sizeof(*sdata) + local->hw.vif_data_size,
1446 				GFP_KERNEL);
1447 		if (!sdata)
1448 			return -ENOMEM;
1449 		wdev = &sdata->wdev;
1450 
1451 		sdata->dev = NULL;
1452 		strlcpy(sdata->name, name, IFNAMSIZ);
1453 		ieee80211_assign_perm_addr(local, wdev->address, type);
1454 		memcpy(sdata->vif.addr, wdev->address, ETH_ALEN);
1455 	} else {
1456 		if (local->hw.queues >= IEEE80211_NUM_ACS)
1457 			txqs = IEEE80211_NUM_ACS;
1458 
1459 		ndev = alloc_netdev_mqs(sizeof(*sdata) +
1460 					local->hw.vif_data_size,
1461 					name, ieee80211_if_setup, txqs, 1);
1462 		if (!ndev)
1463 			return -ENOMEM;
1464 		dev_net_set(ndev, wiphy_net(local->hw.wiphy));
1465 
1466 		ndev->needed_headroom = local->tx_headroom +
1467 					4*6 /* four MAC addresses */
1468 					+ 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
1469 					+ 6 /* mesh */
1470 					+ 8 /* rfc1042/bridge tunnel */
1471 					- ETH_HLEN /* ethernet hard_header_len */
1472 					+ IEEE80211_ENCRYPT_HEADROOM;
1473 		ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
1474 
1475 		ret = dev_alloc_name(ndev, ndev->name);
1476 		if (ret < 0) {
1477 			free_netdev(ndev);
1478 			return ret;
1479 		}
1480 
1481 		ieee80211_assign_perm_addr(local, ndev->perm_addr, type);
1482 		memcpy(ndev->dev_addr, ndev->perm_addr, ETH_ALEN);
1483 		SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
1484 
1485 		/* don't use IEEE80211_DEV_TO_SUB_IF -- it checks too much */
1486 		sdata = netdev_priv(ndev);
1487 		ndev->ieee80211_ptr = &sdata->wdev;
1488 		memcpy(sdata->vif.addr, ndev->dev_addr, ETH_ALEN);
1489 		memcpy(sdata->name, ndev->name, IFNAMSIZ);
1490 
1491 		sdata->dev = ndev;
1492 	}
1493 
1494 	/* initialise type-independent data */
1495 	sdata->wdev.wiphy = local->hw.wiphy;
1496 	sdata->local = local;
1497 #ifdef CONFIG_INET
1498 	sdata->arp_filter_state = true;
1499 #endif
1500 
1501 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
1502 		skb_queue_head_init(&sdata->fragments[i].skb_list);
1503 
1504 	INIT_LIST_HEAD(&sdata->key_list);
1505 
1506 	for (i = 0; i < IEEE80211_NUM_BANDS; i++) {
1507 		struct ieee80211_supported_band *sband;
1508 		sband = local->hw.wiphy->bands[i];
1509 		sdata->rc_rateidx_mask[i] =
1510 			sband ? (1 << sband->n_bitrates) - 1 : 0;
1511 		if (sband)
1512 			memcpy(sdata->rc_rateidx_mcs_mask[i],
1513 			       sband->ht_cap.mcs.rx_mask,
1514 			       sizeof(sdata->rc_rateidx_mcs_mask[i]));
1515 		else
1516 			memset(sdata->rc_rateidx_mcs_mask[i], 0,
1517 			       sizeof(sdata->rc_rateidx_mcs_mask[i]));
1518 	}
1519 
1520 	ieee80211_set_default_queues(sdata);
1521 
1522 	/* setup type-dependent data */
1523 	ieee80211_setup_sdata(sdata, type);
1524 
1525 	if (ndev) {
1526 		if (params) {
1527 			ndev->ieee80211_ptr->use_4addr = params->use_4addr;
1528 			if (type == NL80211_IFTYPE_STATION)
1529 				sdata->u.mgd.use_4addr = params->use_4addr;
1530 		}
1531 
1532 		ndev->features |= local->hw.netdev_features;
1533 
1534 		ret = register_netdevice(ndev);
1535 		if (ret) {
1536 			free_netdev(ndev);
1537 			return ret;
1538 		}
1539 	}
1540 
1541 	mutex_lock(&local->iflist_mtx);
1542 	list_add_tail_rcu(&sdata->list, &local->interfaces);
1543 	mutex_unlock(&local->iflist_mtx);
1544 
1545 	if (new_wdev)
1546 		*new_wdev = &sdata->wdev;
1547 
1548 	return 0;
1549 }
1550 
1551 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
1552 {
1553 	ASSERT_RTNL();
1554 
1555 	mutex_lock(&sdata->local->iflist_mtx);
1556 	list_del_rcu(&sdata->list);
1557 	mutex_unlock(&sdata->local->iflist_mtx);
1558 
1559 	synchronize_rcu();
1560 
1561 	if (sdata->dev) {
1562 		unregister_netdevice(sdata->dev);
1563 	} else {
1564 		cfg80211_unregister_wdev(&sdata->wdev);
1565 		kfree(sdata);
1566 	}
1567 }
1568 
1569 void ieee80211_sdata_stop(struct ieee80211_sub_if_data *sdata)
1570 {
1571 	if (WARN_ON_ONCE(!test_bit(SDATA_STATE_RUNNING, &sdata->state)))
1572 		return;
1573 	ieee80211_do_stop(sdata, true);
1574 	ieee80211_teardown_sdata(sdata);
1575 }
1576 
1577 /*
1578  * Remove all interfaces, may only be called at hardware unregistration
1579  * time because it doesn't do RCU-safe list removals.
1580  */
1581 void ieee80211_remove_interfaces(struct ieee80211_local *local)
1582 {
1583 	struct ieee80211_sub_if_data *sdata, *tmp;
1584 	LIST_HEAD(unreg_list);
1585 	LIST_HEAD(wdev_list);
1586 
1587 	ASSERT_RTNL();
1588 
1589 	mutex_lock(&local->iflist_mtx);
1590 	list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
1591 		list_del(&sdata->list);
1592 
1593 		if (sdata->dev)
1594 			unregister_netdevice_queue(sdata->dev, &unreg_list);
1595 		else
1596 			list_add(&sdata->list, &wdev_list);
1597 	}
1598 	mutex_unlock(&local->iflist_mtx);
1599 	unregister_netdevice_many(&unreg_list);
1600 	list_del(&unreg_list);
1601 
1602 	list_for_each_entry_safe(sdata, tmp, &wdev_list, list) {
1603 		list_del(&sdata->list);
1604 		cfg80211_unregister_wdev(&sdata->wdev);
1605 		kfree(sdata);
1606 	}
1607 }
1608 
1609 static int netdev_notify(struct notifier_block *nb,
1610 			 unsigned long state,
1611 			 void *ndev)
1612 {
1613 	struct net_device *dev = ndev;
1614 	struct ieee80211_sub_if_data *sdata;
1615 
1616 	if (state != NETDEV_CHANGENAME)
1617 		return 0;
1618 
1619 	if (!dev->ieee80211_ptr || !dev->ieee80211_ptr->wiphy)
1620 		return 0;
1621 
1622 	if (dev->ieee80211_ptr->wiphy->privid != mac80211_wiphy_privid)
1623 		return 0;
1624 
1625 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
1626 
1627 	memcpy(sdata->name, dev->name, IFNAMSIZ);
1628 
1629 	ieee80211_debugfs_rename_netdev(sdata);
1630 	return 0;
1631 }
1632 
1633 static struct notifier_block mac80211_netdev_notifier = {
1634 	.notifier_call = netdev_notify,
1635 };
1636 
1637 int ieee80211_iface_init(void)
1638 {
1639 	return register_netdevice_notifier(&mac80211_netdev_notifier);
1640 }
1641 
1642 void ieee80211_iface_exit(void)
1643 {
1644 	unregister_netdevice_notifier(&mac80211_netdev_notifier);
1645 }
1646