xref: /openbmc/linux/net/mac80211/iface.c (revision b6dcefde)
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/kernel.h>
14 #include <linux/if_arp.h>
15 #include <linux/netdevice.h>
16 #include <linux/rtnetlink.h>
17 #include <net/mac80211.h>
18 #include <net/ieee80211_radiotap.h>
19 #include "ieee80211_i.h"
20 #include "sta_info.h"
21 #include "debugfs_netdev.h"
22 #include "mesh.h"
23 #include "led.h"
24 #include "driver-ops.h"
25 #include "wme.h"
26 
27 /**
28  * DOC: Interface list locking
29  *
30  * The interface list in each struct ieee80211_local is protected
31  * three-fold:
32  *
33  * (1) modifications may only be done under the RTNL
34  * (2) modifications and readers are protected against each other by
35  *     the iflist_mtx.
36  * (3) modifications are done in an RCU manner so atomic readers
37  *     can traverse the list in RCU-safe blocks.
38  *
39  * As a consequence, reads (traversals) of the list can be protected
40  * by either the RTNL, the iflist_mtx or RCU.
41  */
42 
43 
44 static int ieee80211_change_mtu(struct net_device *dev, int new_mtu)
45 {
46 	int meshhdrlen;
47 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
48 
49 	meshhdrlen = (sdata->vif.type == NL80211_IFTYPE_MESH_POINT) ? 5 : 0;
50 
51 	/* FIX: what would be proper limits for MTU?
52 	 * This interface uses 802.3 frames. */
53 	if (new_mtu < 256 ||
54 	    new_mtu > IEEE80211_MAX_DATA_LEN - 24 - 6 - meshhdrlen) {
55 		return -EINVAL;
56 	}
57 
58 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
59 	printk(KERN_DEBUG "%s: setting MTU %d\n", dev->name, new_mtu);
60 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
61 	dev->mtu = new_mtu;
62 	return 0;
63 }
64 
65 static inline int identical_mac_addr_allowed(int type1, int type2)
66 {
67 	return type1 == NL80211_IFTYPE_MONITOR ||
68 		type2 == NL80211_IFTYPE_MONITOR ||
69 		(type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_WDS) ||
70 		(type1 == NL80211_IFTYPE_WDS &&
71 			(type2 == NL80211_IFTYPE_WDS ||
72 			 type2 == NL80211_IFTYPE_AP)) ||
73 		(type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_AP_VLAN) ||
74 		(type1 == NL80211_IFTYPE_AP_VLAN &&
75 			(type2 == NL80211_IFTYPE_AP ||
76 			 type2 == NL80211_IFTYPE_AP_VLAN));
77 }
78 
79 static int ieee80211_open(struct net_device *dev)
80 {
81 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
82 	struct ieee80211_sub_if_data *nsdata;
83 	struct ieee80211_local *local = sdata->local;
84 	struct sta_info *sta;
85 	struct ieee80211_if_init_conf conf;
86 	u32 changed = 0;
87 	int res;
88 	u32 hw_reconf_flags = 0;
89 	u8 null_addr[ETH_ALEN] = {0};
90 
91 	/* fail early if user set an invalid address */
92 	if (compare_ether_addr(dev->dev_addr, null_addr) &&
93 	    !is_valid_ether_addr(dev->dev_addr))
94 		return -EADDRNOTAVAIL;
95 
96 	/* we hold the RTNL here so can safely walk the list */
97 	list_for_each_entry(nsdata, &local->interfaces, list) {
98 		struct net_device *ndev = nsdata->dev;
99 
100 		if (ndev != dev && netif_running(ndev)) {
101 			/*
102 			 * Allow only a single IBSS interface to be up at any
103 			 * time. This is restricted because beacon distribution
104 			 * cannot work properly if both are in the same IBSS.
105 			 *
106 			 * To remove this restriction we'd have to disallow them
107 			 * from setting the same SSID on different IBSS interfaces
108 			 * belonging to the same hardware. Then, however, we're
109 			 * faced with having to adopt two different TSF timers...
110 			 */
111 			if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
112 			    nsdata->vif.type == NL80211_IFTYPE_ADHOC)
113 				return -EBUSY;
114 
115 			/*
116 			 * The remaining checks are only performed for interfaces
117 			 * with the same MAC address.
118 			 */
119 			if (compare_ether_addr(dev->dev_addr, ndev->dev_addr))
120 				continue;
121 
122 			/*
123 			 * check whether it may have the same address
124 			 */
125 			if (!identical_mac_addr_allowed(sdata->vif.type,
126 							nsdata->vif.type))
127 				return -ENOTUNIQ;
128 
129 			/*
130 			 * can only add VLANs to enabled APs
131 			 */
132 			if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
133 			    nsdata->vif.type == NL80211_IFTYPE_AP)
134 				sdata->bss = &nsdata->u.ap;
135 		}
136 	}
137 
138 	switch (sdata->vif.type) {
139 	case NL80211_IFTYPE_WDS:
140 		if (!is_valid_ether_addr(sdata->u.wds.remote_addr))
141 			return -ENOLINK;
142 		break;
143 	case NL80211_IFTYPE_AP_VLAN:
144 		if (!sdata->bss)
145 			return -ENOLINK;
146 		list_add(&sdata->u.vlan.list, &sdata->bss->vlans);
147 		break;
148 	case NL80211_IFTYPE_AP:
149 		sdata->bss = &sdata->u.ap;
150 		break;
151 	case NL80211_IFTYPE_MESH_POINT:
152 		if (!ieee80211_vif_is_mesh(&sdata->vif))
153 			break;
154 		/* mesh ifaces must set allmulti to forward mcast traffic */
155 		atomic_inc(&local->iff_allmultis);
156 		break;
157 	case NL80211_IFTYPE_STATION:
158 	case NL80211_IFTYPE_MONITOR:
159 	case NL80211_IFTYPE_ADHOC:
160 		/* no special treatment */
161 		break;
162 	case NL80211_IFTYPE_UNSPECIFIED:
163 	case __NL80211_IFTYPE_AFTER_LAST:
164 		/* cannot happen */
165 		WARN_ON(1);
166 		break;
167 	}
168 
169 	if (local->open_count == 0) {
170 		res = drv_start(local);
171 		if (res)
172 			goto err_del_bss;
173 		/* we're brought up, everything changes */
174 		hw_reconf_flags = ~0;
175 		ieee80211_led_radio(local, true);
176 	}
177 
178 	/*
179 	 * Check all interfaces and copy the hopefully now-present
180 	 * MAC address to those that have the special null one.
181 	 */
182 	list_for_each_entry(nsdata, &local->interfaces, list) {
183 		struct net_device *ndev = nsdata->dev;
184 
185 		/*
186 		 * No need to check netif_running since we do not allow
187 		 * it to start up with this invalid address.
188 		 */
189 		if (compare_ether_addr(null_addr, ndev->dev_addr) == 0) {
190 			memcpy(ndev->dev_addr,
191 			       local->hw.wiphy->perm_addr,
192 			       ETH_ALEN);
193 			memcpy(ndev->perm_addr, ndev->dev_addr, ETH_ALEN);
194 		}
195 	}
196 
197 	/*
198 	 * Validate the MAC address for this device.
199 	 */
200 	if (!is_valid_ether_addr(dev->dev_addr)) {
201 		if (!local->open_count)
202 			drv_stop(local);
203 		return -EADDRNOTAVAIL;
204 	}
205 
206 	switch (sdata->vif.type) {
207 	case NL80211_IFTYPE_AP_VLAN:
208 		/* no need to tell driver */
209 		break;
210 	case NL80211_IFTYPE_MONITOR:
211 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
212 			local->cooked_mntrs++;
213 			break;
214 		}
215 
216 		/* must be before the call to ieee80211_configure_filter */
217 		local->monitors++;
218 		if (local->monitors == 1) {
219 			local->hw.conf.flags |= IEEE80211_CONF_MONITOR;
220 			hw_reconf_flags |= IEEE80211_CONF_CHANGE_MONITOR;
221 		}
222 
223 		if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
224 			local->fif_fcsfail++;
225 		if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
226 			local->fif_plcpfail++;
227 		if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL) {
228 			local->fif_control++;
229 			local->fif_pspoll++;
230 		}
231 		if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
232 			local->fif_other_bss++;
233 
234 		ieee80211_configure_filter(local);
235 		break;
236 	default:
237 		conf.vif = &sdata->vif;
238 		conf.type = sdata->vif.type;
239 		conf.mac_addr = dev->dev_addr;
240 		res = drv_add_interface(local, &conf);
241 		if (res)
242 			goto err_stop;
243 
244 		if (ieee80211_vif_is_mesh(&sdata->vif)) {
245 			local->fif_other_bss++;
246 			ieee80211_configure_filter(local);
247 
248 			ieee80211_start_mesh(sdata);
249 		} else if (sdata->vif.type == NL80211_IFTYPE_AP) {
250 			local->fif_pspoll++;
251 
252 			ieee80211_configure_filter(local);
253 		}
254 
255 		changed |= ieee80211_reset_erp_info(sdata);
256 		ieee80211_bss_info_change_notify(sdata, changed);
257 		ieee80211_enable_keys(sdata);
258 
259 		if (sdata->vif.type == NL80211_IFTYPE_STATION)
260 			netif_carrier_off(dev);
261 		else
262 			netif_carrier_on(dev);
263 	}
264 
265 	if (sdata->vif.type == NL80211_IFTYPE_WDS) {
266 		/* Create STA entry for the WDS peer */
267 		sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
268 				     GFP_KERNEL);
269 		if (!sta) {
270 			res = -ENOMEM;
271 			goto err_del_interface;
272 		}
273 
274 		/* no locking required since STA is not live yet */
275 		sta->flags |= WLAN_STA_AUTHORIZED;
276 
277 		res = sta_info_insert(sta);
278 		if (res) {
279 			/* STA has been freed */
280 			goto err_del_interface;
281 		}
282 	}
283 
284 	/*
285 	 * set_multicast_list will be invoked by the networking core
286 	 * which will check whether any increments here were done in
287 	 * error and sync them down to the hardware as filter flags.
288 	 */
289 	if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
290 		atomic_inc(&local->iff_allmultis);
291 
292 	if (sdata->flags & IEEE80211_SDATA_PROMISC)
293 		atomic_inc(&local->iff_promiscs);
294 
295 	hw_reconf_flags |= __ieee80211_recalc_idle(local);
296 
297 	local->open_count++;
298 	if (hw_reconf_flags) {
299 		ieee80211_hw_config(local, hw_reconf_flags);
300 		/*
301 		 * set default queue parameters so drivers don't
302 		 * need to initialise the hardware if the hardware
303 		 * doesn't start up with sane defaults
304 		 */
305 		ieee80211_set_wmm_default(sdata);
306 	}
307 
308 	ieee80211_recalc_ps(local, -1);
309 
310 	/*
311 	 * ieee80211_sta_work is disabled while network interface
312 	 * is down. Therefore, some configuration changes may not
313 	 * yet be effective. Trigger execution of ieee80211_sta_work
314 	 * to fix this.
315 	 */
316 	if (sdata->vif.type == NL80211_IFTYPE_STATION)
317 		ieee80211_queue_work(&local->hw, &sdata->u.mgd.work);
318 
319 	netif_tx_start_all_queues(dev);
320 
321 	return 0;
322  err_del_interface:
323 	drv_remove_interface(local, &conf);
324  err_stop:
325 	if (!local->open_count)
326 		drv_stop(local);
327  err_del_bss:
328 	sdata->bss = NULL;
329 	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
330 		list_del(&sdata->u.vlan.list);
331 	return res;
332 }
333 
334 static int ieee80211_stop(struct net_device *dev)
335 {
336 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
337 	struct ieee80211_local *local = sdata->local;
338 	struct ieee80211_if_init_conf conf;
339 	struct sta_info *sta;
340 	unsigned long flags;
341 	struct sk_buff *skb, *tmp;
342 	u32 hw_reconf_flags = 0;
343 	int i;
344 
345 	/*
346 	 * Stop TX on this interface first.
347 	 */
348 	netif_tx_stop_all_queues(dev);
349 
350 	/*
351 	 * Now delete all active aggregation sessions.
352 	 */
353 	rcu_read_lock();
354 
355 	list_for_each_entry_rcu(sta, &local->sta_list, list) {
356 		if (sta->sdata == sdata)
357 			ieee80211_sta_tear_down_BA_sessions(sta);
358 	}
359 
360 	rcu_read_unlock();
361 
362 	/*
363 	 * Remove all stations associated with this interface.
364 	 *
365 	 * This must be done before calling ops->remove_interface()
366 	 * because otherwise we can later invoke ops->sta_notify()
367 	 * whenever the STAs are removed, and that invalidates driver
368 	 * assumptions about always getting a vif pointer that is valid
369 	 * (because if we remove a STA after ops->remove_interface()
370 	 * the driver will have removed the vif info already!)
371 	 *
372 	 * We could relax this and only unlink the stations from the
373 	 * hash table and list but keep them on a per-sdata list that
374 	 * will be inserted back again when the interface is brought
375 	 * up again, but I don't currently see a use case for that,
376 	 * except with WDS which gets a STA entry created when it is
377 	 * brought up.
378 	 */
379 	sta_info_flush(local, sdata);
380 
381 	/*
382 	 * Don't count this interface for promisc/allmulti while it
383 	 * is down. dev_mc_unsync() will invoke set_multicast_list
384 	 * on the master interface which will sync these down to the
385 	 * hardware as filter flags.
386 	 */
387 	if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
388 		atomic_dec(&local->iff_allmultis);
389 
390 	if (sdata->flags & IEEE80211_SDATA_PROMISC)
391 		atomic_dec(&local->iff_promiscs);
392 
393 	if (sdata->vif.type == NL80211_IFTYPE_AP)
394 		local->fif_pspoll--;
395 
396 	netif_addr_lock_bh(dev);
397 	spin_lock_bh(&local->filter_lock);
398 	__dev_addr_unsync(&local->mc_list, &local->mc_count,
399 			  &dev->mc_list, &dev->mc_count);
400 	spin_unlock_bh(&local->filter_lock);
401 	netif_addr_unlock_bh(dev);
402 
403 	ieee80211_configure_filter(local);
404 
405 	del_timer_sync(&local->dynamic_ps_timer);
406 	cancel_work_sync(&local->dynamic_ps_enable_work);
407 
408 	/* APs need special treatment */
409 	if (sdata->vif.type == NL80211_IFTYPE_AP) {
410 		struct ieee80211_sub_if_data *vlan, *tmpsdata;
411 		struct beacon_data *old_beacon = sdata->u.ap.beacon;
412 
413 		/* remove beacon */
414 		rcu_assign_pointer(sdata->u.ap.beacon, NULL);
415 		synchronize_rcu();
416 		kfree(old_beacon);
417 
418 		/* down all dependent devices, that is VLANs */
419 		list_for_each_entry_safe(vlan, tmpsdata, &sdata->u.ap.vlans,
420 					 u.vlan.list)
421 			dev_close(vlan->dev);
422 		WARN_ON(!list_empty(&sdata->u.ap.vlans));
423 	}
424 
425 	local->open_count--;
426 
427 	switch (sdata->vif.type) {
428 	case NL80211_IFTYPE_AP_VLAN:
429 		list_del(&sdata->u.vlan.list);
430 		/* no need to tell driver */
431 		break;
432 	case NL80211_IFTYPE_MONITOR:
433 		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
434 			local->cooked_mntrs--;
435 			break;
436 		}
437 
438 		local->monitors--;
439 		if (local->monitors == 0) {
440 			local->hw.conf.flags &= ~IEEE80211_CONF_MONITOR;
441 			hw_reconf_flags |= IEEE80211_CONF_CHANGE_MONITOR;
442 		}
443 
444 		if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
445 			local->fif_fcsfail--;
446 		if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
447 			local->fif_plcpfail--;
448 		if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL) {
449 			local->fif_pspoll--;
450 			local->fif_control--;
451 		}
452 		if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
453 			local->fif_other_bss--;
454 
455 		ieee80211_configure_filter(local);
456 		break;
457 	case NL80211_IFTYPE_STATION:
458 		del_timer_sync(&sdata->u.mgd.chswitch_timer);
459 		del_timer_sync(&sdata->u.mgd.timer);
460 		del_timer_sync(&sdata->u.mgd.conn_mon_timer);
461 		del_timer_sync(&sdata->u.mgd.bcn_mon_timer);
462 		/*
463 		 * If any of the timers fired while we waited for it, it will
464 		 * have queued its work. Now the work will be running again
465 		 * but will not rearm the timer again because it checks
466 		 * whether the interface is running, which, at this point,
467 		 * it no longer is.
468 		 */
469 		cancel_work_sync(&sdata->u.mgd.work);
470 		cancel_work_sync(&sdata->u.mgd.chswitch_work);
471 		cancel_work_sync(&sdata->u.mgd.monitor_work);
472 		cancel_work_sync(&sdata->u.mgd.beacon_loss_work);
473 
474 		/*
475 		 * When we get here, the interface is marked down.
476 		 * Call synchronize_rcu() to wait for the RX path
477 		 * should it be using the interface and enqueuing
478 		 * frames at this very time on another CPU.
479 		 */
480 		synchronize_rcu();
481 		skb_queue_purge(&sdata->u.mgd.skb_queue);
482 		/* fall through */
483 	case NL80211_IFTYPE_ADHOC:
484 		if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
485 			del_timer_sync(&sdata->u.ibss.timer);
486 			cancel_work_sync(&sdata->u.ibss.work);
487 			synchronize_rcu();
488 			skb_queue_purge(&sdata->u.ibss.skb_queue);
489 		}
490 		/* fall through */
491 	case NL80211_IFTYPE_MESH_POINT:
492 		if (ieee80211_vif_is_mesh(&sdata->vif)) {
493 			/* other_bss and allmulti are always set on mesh
494 			 * ifaces */
495 			local->fif_other_bss--;
496 			atomic_dec(&local->iff_allmultis);
497 
498 			ieee80211_configure_filter(local);
499 
500 			ieee80211_stop_mesh(sdata);
501 		}
502 		/* fall through */
503 	default:
504 		if (local->scan_sdata == sdata)
505 			ieee80211_scan_cancel(local);
506 
507 		/*
508 		 * Disable beaconing for AP and mesh, IBSS can't
509 		 * still be joined to a network at this point.
510 		 */
511 		if (sdata->vif.type == NL80211_IFTYPE_AP ||
512 		    sdata->vif.type == NL80211_IFTYPE_MESH_POINT) {
513 			ieee80211_bss_info_change_notify(sdata,
514 				BSS_CHANGED_BEACON_ENABLED);
515 		}
516 
517 		conf.vif = &sdata->vif;
518 		conf.type = sdata->vif.type;
519 		conf.mac_addr = dev->dev_addr;
520 		/* disable all keys for as long as this netdev is down */
521 		ieee80211_disable_keys(sdata);
522 		drv_remove_interface(local, &conf);
523 	}
524 
525 	sdata->bss = NULL;
526 
527 	hw_reconf_flags |= __ieee80211_recalc_idle(local);
528 
529 	ieee80211_recalc_ps(local, -1);
530 
531 	if (local->open_count == 0) {
532 		ieee80211_clear_tx_pending(local);
533 		ieee80211_stop_device(local);
534 
535 		/* no reconfiguring after stop! */
536 		hw_reconf_flags = 0;
537 	}
538 
539 	/* do after stop to avoid reconfiguring when we stop anyway */
540 	if (hw_reconf_flags)
541 		ieee80211_hw_config(local, hw_reconf_flags);
542 
543 	spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
544 	for (i = 0; i < IEEE80211_MAX_QUEUES; i++) {
545 		skb_queue_walk_safe(&local->pending[i], skb, tmp) {
546 			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
547 			if (info->control.vif == &sdata->vif) {
548 				__skb_unlink(skb, &local->pending[i]);
549 				dev_kfree_skb_irq(skb);
550 			}
551 		}
552 	}
553 	spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
554 
555 	return 0;
556 }
557 
558 static void ieee80211_set_multicast_list(struct net_device *dev)
559 {
560 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
561 	struct ieee80211_local *local = sdata->local;
562 	int allmulti, promisc, sdata_allmulti, sdata_promisc;
563 
564 	allmulti = !!(dev->flags & IFF_ALLMULTI);
565 	promisc = !!(dev->flags & IFF_PROMISC);
566 	sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
567 	sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
568 
569 	if (allmulti != sdata_allmulti) {
570 		if (dev->flags & IFF_ALLMULTI)
571 			atomic_inc(&local->iff_allmultis);
572 		else
573 			atomic_dec(&local->iff_allmultis);
574 		sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
575 	}
576 
577 	if (promisc != sdata_promisc) {
578 		if (dev->flags & IFF_PROMISC)
579 			atomic_inc(&local->iff_promiscs);
580 		else
581 			atomic_dec(&local->iff_promiscs);
582 		sdata->flags ^= IEEE80211_SDATA_PROMISC;
583 	}
584 	spin_lock_bh(&local->filter_lock);
585 	__dev_addr_sync(&local->mc_list, &local->mc_count,
586 			&dev->mc_list, &dev->mc_count);
587 	spin_unlock_bh(&local->filter_lock);
588 	ieee80211_queue_work(&local->hw, &local->reconfig_filter);
589 }
590 
591 /*
592  * Called when the netdev is removed or, by the code below, before
593  * the interface type changes.
594  */
595 static void ieee80211_teardown_sdata(struct net_device *dev)
596 {
597 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
598 	struct ieee80211_local *local = sdata->local;
599 	struct beacon_data *beacon;
600 	struct sk_buff *skb;
601 	int flushed;
602 	int i;
603 
604 	/* free extra data */
605 	ieee80211_free_keys(sdata);
606 
607 	ieee80211_debugfs_remove_netdev(sdata);
608 
609 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
610 		__skb_queue_purge(&sdata->fragments[i].skb_list);
611 	sdata->fragment_next = 0;
612 
613 	switch (sdata->vif.type) {
614 	case NL80211_IFTYPE_AP:
615 		beacon = sdata->u.ap.beacon;
616 		rcu_assign_pointer(sdata->u.ap.beacon, NULL);
617 		synchronize_rcu();
618 		kfree(beacon);
619 
620 		while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
621 			local->total_ps_buffered--;
622 			dev_kfree_skb(skb);
623 		}
624 
625 		break;
626 	case NL80211_IFTYPE_MESH_POINT:
627 		if (ieee80211_vif_is_mesh(&sdata->vif))
628 			mesh_rmc_free(sdata);
629 		break;
630 	case NL80211_IFTYPE_ADHOC:
631 		if (WARN_ON(sdata->u.ibss.presp))
632 			kfree_skb(sdata->u.ibss.presp);
633 		break;
634 	case NL80211_IFTYPE_STATION:
635 	case NL80211_IFTYPE_WDS:
636 	case NL80211_IFTYPE_AP_VLAN:
637 	case NL80211_IFTYPE_MONITOR:
638 		break;
639 	case NL80211_IFTYPE_UNSPECIFIED:
640 	case __NL80211_IFTYPE_AFTER_LAST:
641 		BUG();
642 		break;
643 	}
644 
645 	flushed = sta_info_flush(local, sdata);
646 	WARN_ON(flushed);
647 }
648 
649 static u16 ieee80211_netdev_select_queue(struct net_device *dev,
650 					 struct sk_buff *skb)
651 {
652 	return ieee80211_select_queue(IEEE80211_DEV_TO_SUB_IF(dev), skb);
653 }
654 
655 static const struct net_device_ops ieee80211_dataif_ops = {
656 	.ndo_open		= ieee80211_open,
657 	.ndo_stop		= ieee80211_stop,
658 	.ndo_uninit		= ieee80211_teardown_sdata,
659 	.ndo_start_xmit		= ieee80211_subif_start_xmit,
660 	.ndo_set_multicast_list = ieee80211_set_multicast_list,
661 	.ndo_change_mtu 	= ieee80211_change_mtu,
662 	.ndo_set_mac_address 	= eth_mac_addr,
663 	.ndo_select_queue	= ieee80211_netdev_select_queue,
664 };
665 
666 static u16 ieee80211_monitor_select_queue(struct net_device *dev,
667 					  struct sk_buff *skb)
668 {
669 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
670 	struct ieee80211_local *local = sdata->local;
671 	struct ieee80211_hdr *hdr;
672 	struct ieee80211_radiotap_header *rtap = (void *)skb->data;
673 	u8 *p;
674 
675 	if (local->hw.queues < 4)
676 		return 0;
677 
678 	if (skb->len < 4 ||
679 	    skb->len < le16_to_cpu(rtap->it_len) + 2 /* frame control */)
680 		return 0; /* doesn't matter, frame will be dropped */
681 
682 	hdr = (void *)((u8 *)skb->data + le16_to_cpu(rtap->it_len));
683 
684 	if (!ieee80211_is_data_qos(hdr->frame_control)) {
685 		skb->priority = 7;
686 		return ieee802_1d_to_ac[skb->priority];
687 	}
688 
689 	p = ieee80211_get_qos_ctl(hdr);
690 	skb->priority = *p & IEEE80211_QOS_CTL_TAG1D_MASK;
691 
692 	return ieee80211_downgrade_queue(local, skb);
693 }
694 
695 static const struct net_device_ops ieee80211_monitorif_ops = {
696 	.ndo_open		= ieee80211_open,
697 	.ndo_stop		= ieee80211_stop,
698 	.ndo_uninit		= ieee80211_teardown_sdata,
699 	.ndo_start_xmit		= ieee80211_monitor_start_xmit,
700 	.ndo_set_multicast_list = ieee80211_set_multicast_list,
701 	.ndo_change_mtu 	= ieee80211_change_mtu,
702 	.ndo_set_mac_address 	= eth_mac_addr,
703 	.ndo_select_queue	= ieee80211_monitor_select_queue,
704 };
705 
706 static void ieee80211_if_setup(struct net_device *dev)
707 {
708 	ether_setup(dev);
709 	dev->netdev_ops = &ieee80211_dataif_ops;
710 	dev->destructor = free_netdev;
711 }
712 
713 /*
714  * Helper function to initialise an interface to a specific type.
715  */
716 static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,
717 				  enum nl80211_iftype type)
718 {
719 	/* clear type-dependent union */
720 	memset(&sdata->u, 0, sizeof(sdata->u));
721 
722 	/* and set some type-dependent values */
723 	sdata->vif.type = type;
724 	sdata->dev->netdev_ops = &ieee80211_dataif_ops;
725 	sdata->wdev.iftype = type;
726 
727 	/* only monitor differs */
728 	sdata->dev->type = ARPHRD_ETHER;
729 
730 	switch (type) {
731 	case NL80211_IFTYPE_AP:
732 		skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
733 		INIT_LIST_HEAD(&sdata->u.ap.vlans);
734 		break;
735 	case NL80211_IFTYPE_STATION:
736 		ieee80211_sta_setup_sdata(sdata);
737 		break;
738 	case NL80211_IFTYPE_ADHOC:
739 		ieee80211_ibss_setup_sdata(sdata);
740 		break;
741 	case NL80211_IFTYPE_MESH_POINT:
742 		if (ieee80211_vif_is_mesh(&sdata->vif))
743 			ieee80211_mesh_init_sdata(sdata);
744 		break;
745 	case NL80211_IFTYPE_MONITOR:
746 		sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;
747 		sdata->dev->netdev_ops = &ieee80211_monitorif_ops;
748 		sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
749 				      MONITOR_FLAG_OTHER_BSS;
750 		break;
751 	case NL80211_IFTYPE_WDS:
752 	case NL80211_IFTYPE_AP_VLAN:
753 		break;
754 	case NL80211_IFTYPE_UNSPECIFIED:
755 	case __NL80211_IFTYPE_AFTER_LAST:
756 		BUG();
757 		break;
758 	}
759 
760 	ieee80211_debugfs_add_netdev(sdata);
761 }
762 
763 int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,
764 			     enum nl80211_iftype type)
765 {
766 	ASSERT_RTNL();
767 
768 	if (type == sdata->vif.type)
769 		return 0;
770 
771 	/* Setting ad-hoc mode on non-IBSS channel is not supported. */
772 	if (sdata->local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS &&
773 	    type == NL80211_IFTYPE_ADHOC)
774 		return -EOPNOTSUPP;
775 
776 	/*
777 	 * We could, here, on changes between IBSS/STA/MESH modes,
778 	 * invoke an MLME function instead that disassociates etc.
779 	 * and goes into the requested mode.
780 	 */
781 
782 	if (netif_running(sdata->dev))
783 		return -EBUSY;
784 
785 	/* Purge and reset type-dependent state. */
786 	ieee80211_teardown_sdata(sdata->dev);
787 	ieee80211_setup_sdata(sdata, type);
788 
789 	/* reset some values that shouldn't be kept across type changes */
790 	sdata->vif.bss_conf.basic_rates =
791 		ieee80211_mandatory_rates(sdata->local,
792 			sdata->local->hw.conf.channel->band);
793 	sdata->drop_unencrypted = 0;
794 	if (type == NL80211_IFTYPE_STATION)
795 		sdata->u.mgd.use_4addr = false;
796 
797 	return 0;
798 }
799 
800 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
801 		     struct net_device **new_dev, enum nl80211_iftype type,
802 		     struct vif_params *params)
803 {
804 	struct net_device *ndev;
805 	struct ieee80211_sub_if_data *sdata = NULL;
806 	int ret, i;
807 
808 	ASSERT_RTNL();
809 
810 	ndev = alloc_netdev_mq(sizeof(*sdata) + local->hw.vif_data_size,
811 			       name, ieee80211_if_setup, local->hw.queues);
812 	if (!ndev)
813 		return -ENOMEM;
814 	dev_net_set(ndev, wiphy_net(local->hw.wiphy));
815 
816 	ndev->needed_headroom = local->tx_headroom +
817 				4*6 /* four MAC addresses */
818 				+ 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
819 				+ 6 /* mesh */
820 				+ 8 /* rfc1042/bridge tunnel */
821 				- ETH_HLEN /* ethernet hard_header_len */
822 				+ IEEE80211_ENCRYPT_HEADROOM;
823 	ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;
824 
825 	ret = dev_alloc_name(ndev, ndev->name);
826 	if (ret < 0)
827 		goto fail;
828 
829 	memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
830 	memcpy(ndev->perm_addr, ndev->dev_addr, ETH_ALEN);
831 	SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
832 
833 	/* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
834 	sdata = netdev_priv(ndev);
835 	ndev->ieee80211_ptr = &sdata->wdev;
836 
837 	/* initialise type-independent data */
838 	sdata->wdev.wiphy = local->hw.wiphy;
839 	sdata->local = local;
840 	sdata->dev = ndev;
841 
842 	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
843 		skb_queue_head_init(&sdata->fragments[i].skb_list);
844 
845 	INIT_LIST_HEAD(&sdata->key_list);
846 
847 	sdata->force_unicast_rateidx = -1;
848 	sdata->max_ratectrl_rateidx = -1;
849 
850 	/* setup type-dependent data */
851 	ieee80211_setup_sdata(sdata, type);
852 
853 	if (params) {
854 		ndev->ieee80211_ptr->use_4addr = params->use_4addr;
855 		if (type == NL80211_IFTYPE_STATION)
856 			sdata->u.mgd.use_4addr = params->use_4addr;
857 	}
858 
859 	ret = register_netdevice(ndev);
860 	if (ret)
861 		goto fail;
862 
863 	if (ieee80211_vif_is_mesh(&sdata->vif) &&
864 	    params && params->mesh_id_len)
865 		ieee80211_sdata_set_mesh_id(sdata,
866 					    params->mesh_id_len,
867 					    params->mesh_id);
868 
869 	mutex_lock(&local->iflist_mtx);
870 	list_add_tail_rcu(&sdata->list, &local->interfaces);
871 	mutex_unlock(&local->iflist_mtx);
872 
873 	if (new_dev)
874 		*new_dev = ndev;
875 
876 	return 0;
877 
878  fail:
879 	free_netdev(ndev);
880 	return ret;
881 }
882 
883 void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)
884 {
885 	ASSERT_RTNL();
886 
887 	mutex_lock(&sdata->local->iflist_mtx);
888 	list_del_rcu(&sdata->list);
889 	mutex_unlock(&sdata->local->iflist_mtx);
890 
891 	synchronize_rcu();
892 	unregister_netdevice(sdata->dev);
893 }
894 
895 /*
896  * Remove all interfaces, may only be called at hardware unregistration
897  * time because it doesn't do RCU-safe list removals.
898  */
899 void ieee80211_remove_interfaces(struct ieee80211_local *local)
900 {
901 	struct ieee80211_sub_if_data *sdata, *tmp;
902 	LIST_HEAD(unreg_list);
903 
904 	ASSERT_RTNL();
905 
906 	mutex_lock(&local->iflist_mtx);
907 	list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {
908 		list_del(&sdata->list);
909 
910 		unregister_netdevice_queue(sdata->dev, &unreg_list);
911 	}
912 	mutex_unlock(&local->iflist_mtx);
913 	unregister_netdevice_many(&unreg_list);
914 }
915 
916 static u32 ieee80211_idle_off(struct ieee80211_local *local,
917 			      const char *reason)
918 {
919 	if (!(local->hw.conf.flags & IEEE80211_CONF_IDLE))
920 		return 0;
921 
922 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
923 	printk(KERN_DEBUG "%s: device no longer idle - %s\n",
924 	       wiphy_name(local->hw.wiphy), reason);
925 #endif
926 
927 	local->hw.conf.flags &= ~IEEE80211_CONF_IDLE;
928 	return IEEE80211_CONF_CHANGE_IDLE;
929 }
930 
931 static u32 ieee80211_idle_on(struct ieee80211_local *local)
932 {
933 	if (local->hw.conf.flags & IEEE80211_CONF_IDLE)
934 		return 0;
935 
936 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
937 	printk(KERN_DEBUG "%s: device now idle\n",
938 	       wiphy_name(local->hw.wiphy));
939 #endif
940 
941 	local->hw.conf.flags |= IEEE80211_CONF_IDLE;
942 	return IEEE80211_CONF_CHANGE_IDLE;
943 }
944 
945 u32 __ieee80211_recalc_idle(struct ieee80211_local *local)
946 {
947 	struct ieee80211_sub_if_data *sdata;
948 	int count = 0;
949 
950 	if (local->scanning)
951 		return ieee80211_idle_off(local, "scanning");
952 
953 	list_for_each_entry(sdata, &local->interfaces, list) {
954 		if (!netif_running(sdata->dev))
955 			continue;
956 		/* do not count disabled managed interfaces */
957 		if (sdata->vif.type == NL80211_IFTYPE_STATION &&
958 		    !sdata->u.mgd.associated &&
959 		    list_empty(&sdata->u.mgd.work_list))
960 			continue;
961 		/* do not count unused IBSS interfaces */
962 		if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
963 		    !sdata->u.ibss.ssid_len)
964 			continue;
965 		/* count everything else */
966 		count++;
967 	}
968 
969 	if (!count)
970 		return ieee80211_idle_on(local);
971 	else
972 		return ieee80211_idle_off(local, "in use");
973 
974 	return 0;
975 }
976 
977 void ieee80211_recalc_idle(struct ieee80211_local *local)
978 {
979 	u32 chg;
980 
981 	mutex_lock(&local->iflist_mtx);
982 	chg = __ieee80211_recalc_idle(local);
983 	mutex_unlock(&local->iflist_mtx);
984 	if (chg)
985 		ieee80211_hw_config(local, chg);
986 }
987