sta_info.c revision 499f42bb03a9bd8a23f73e7c3886f70f52e7edc5
1/*
2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 */
9
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/etherdevice.h>
13#include <linux/netdevice.h>
14#include <linux/types.h>
15#include <linux/slab.h>
16#include <linux/skbuff.h>
17#include <linux/if_arp.h>
18#include <linux/timer.h>
19#include <linux/rtnetlink.h>
20
21#include <net/mac80211.h>
22#include "ieee80211_i.h"
23#include "driver-ops.h"
24#include "rate.h"
25#include "sta_info.h"
26#include "debugfs_sta.h"
27#include "mesh.h"
28#include "wme.h"
29
30/**
31 * DOC: STA information lifetime rules
32 *
33 * STA info structures (&struct sta_info) are managed in a hash table
34 * for faster lookup and a list for iteration. They are managed using
35 * RCU, i.e. access to the list and hash table is protected by RCU.
36 *
37 * Upon allocating a STA info structure with sta_info_alloc(), the caller
38 * owns that structure. It must then insert it into the hash table using
39 * either sta_info_insert() or sta_info_insert_rcu(); only in the latter
40 * case (which acquires an rcu read section but must not be called from
41 * within one) will the pointer still be valid after the call. Note that
42 * the caller may not do much with the STA info before inserting it, in
43 * particular, it may not start any mesh peer link management or add
44 * encryption keys.
45 *
46 * When the insertion fails (sta_info_insert()) returns non-zero), the
47 * structure will have been freed by sta_info_insert()!
48 *
49 * Station entries are added by mac80211 when you establish a link with a
50 * peer. This means different things for the different type of interfaces
51 * we support. For a regular station this mean we add the AP sta when we
52 * receive an association response from the AP. For IBSS this occurs when
53 * get to know about a peer on the same IBSS. For WDS we add the sta for
54 * the peer immediately upon device open. When using AP mode we add stations
55 * for each respective station upon request from userspace through nl80211.
56 *
57 * In order to remove a STA info structure, various sta_info_destroy_*()
58 * calls are available.
59 *
60 * There is no concept of ownership on a STA entry, each structure is
61 * owned by the global hash table/list until it is removed. All users of
62 * the structure need to be RCU protected so that the structure won't be
63 * freed before they are done using it.
64 */
65
66/* Caller must hold local->sta_mtx */
67static int sta_info_hash_del(struct ieee80211_local *local,
68			     struct sta_info *sta)
69{
70	struct sta_info *s;
71
72	s = rcu_dereference_protected(local->sta_hash[STA_HASH(sta->sta.addr)],
73				      lockdep_is_held(&local->sta_mtx));
74	if (!s)
75		return -ENOENT;
76	if (s == sta) {
77		rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)],
78				   s->hnext);
79		return 0;
80	}
81
82	while (rcu_access_pointer(s->hnext) &&
83	       rcu_access_pointer(s->hnext) != sta)
84		s = rcu_dereference_protected(s->hnext,
85					lockdep_is_held(&local->sta_mtx));
86	if (rcu_access_pointer(s->hnext)) {
87		rcu_assign_pointer(s->hnext, sta->hnext);
88		return 0;
89	}
90
91	return -ENOENT;
92}
93
94/* protected by RCU */
95struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata,
96			      const u8 *addr)
97{
98	struct ieee80211_local *local = sdata->local;
99	struct sta_info *sta;
100
101	sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)],
102				    lockdep_is_held(&local->sta_mtx));
103	while (sta) {
104		if (sta->sdata == sdata &&
105		    ether_addr_equal(sta->sta.addr, addr))
106			break;
107		sta = rcu_dereference_check(sta->hnext,
108					    lockdep_is_held(&local->sta_mtx));
109	}
110	return sta;
111}
112
113/*
114 * Get sta info either from the specified interface
115 * or from one of its vlans
116 */
117struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata,
118				  const u8 *addr)
119{
120	struct ieee80211_local *local = sdata->local;
121	struct sta_info *sta;
122
123	sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)],
124				    lockdep_is_held(&local->sta_mtx));
125	while (sta) {
126		if ((sta->sdata == sdata ||
127		     (sta->sdata->bss && sta->sdata->bss == sdata->bss)) &&
128		    ether_addr_equal(sta->sta.addr, addr))
129			break;
130		sta = rcu_dereference_check(sta->hnext,
131					    lockdep_is_held(&local->sta_mtx));
132	}
133	return sta;
134}
135
136struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata,
137				     int idx)
138{
139	struct ieee80211_local *local = sdata->local;
140	struct sta_info *sta;
141	int i = 0;
142
143	list_for_each_entry_rcu(sta, &local->sta_list, list) {
144		if (sdata != sta->sdata)
145			continue;
146		if (i < idx) {
147			++i;
148			continue;
149		}
150		return sta;
151	}
152
153	return NULL;
154}
155
156/**
157 * sta_info_free - free STA
158 *
159 * @local: pointer to the global information
160 * @sta: STA info to free
161 *
162 * This function must undo everything done by sta_info_alloc()
163 * that may happen before sta_info_insert(). It may only be
164 * called when sta_info_insert() has not been attempted (and
165 * if that fails, the station is freed anyway.)
166 */
167void sta_info_free(struct ieee80211_local *local, struct sta_info *sta)
168{
169	if (sta->rate_ctrl)
170		rate_control_free_sta(sta);
171
172#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
173	wiphy_debug(local->hw.wiphy, "Destroyed STA %pM\n", sta->sta.addr);
174#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
175
176	kfree(sta);
177}
178
179/* Caller must hold local->sta_mtx */
180static void sta_info_hash_add(struct ieee80211_local *local,
181			      struct sta_info *sta)
182{
183	lockdep_assert_held(&local->sta_mtx);
184	sta->hnext = local->sta_hash[STA_HASH(sta->sta.addr)];
185	rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], sta);
186}
187
188static void sta_unblock(struct work_struct *wk)
189{
190	struct sta_info *sta;
191
192	sta = container_of(wk, struct sta_info, drv_unblock_wk);
193
194	if (sta->dead)
195		return;
196
197	if (!test_sta_flag(sta, WLAN_STA_PS_STA)) {
198		local_bh_disable();
199		ieee80211_sta_ps_deliver_wakeup(sta);
200		local_bh_enable();
201	} else if (test_and_clear_sta_flag(sta, WLAN_STA_PSPOLL)) {
202		clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
203
204		local_bh_disable();
205		ieee80211_sta_ps_deliver_poll_response(sta);
206		local_bh_enable();
207	} else if (test_and_clear_sta_flag(sta, WLAN_STA_UAPSD)) {
208		clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
209
210		local_bh_disable();
211		ieee80211_sta_ps_deliver_uapsd(sta);
212		local_bh_enable();
213	} else
214		clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
215}
216
217static int sta_prepare_rate_control(struct ieee80211_local *local,
218				    struct sta_info *sta, gfp_t gfp)
219{
220	if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL)
221		return 0;
222
223	sta->rate_ctrl = local->rate_ctrl;
224	sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl,
225						     &sta->sta, gfp);
226	if (!sta->rate_ctrl_priv)
227		return -ENOMEM;
228
229	return 0;
230}
231
232struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
233				const u8 *addr, gfp_t gfp)
234{
235	struct ieee80211_local *local = sdata->local;
236	struct sta_info *sta;
237	struct timespec uptime;
238	int i;
239
240	sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp);
241	if (!sta)
242		return NULL;
243
244	spin_lock_init(&sta->lock);
245	INIT_WORK(&sta->drv_unblock_wk, sta_unblock);
246	INIT_WORK(&sta->ampdu_mlme.work, ieee80211_ba_session_work);
247	mutex_init(&sta->ampdu_mlme.mtx);
248
249	memcpy(sta->sta.addr, addr, ETH_ALEN);
250	sta->local = local;
251	sta->sdata = sdata;
252	sta->last_rx = jiffies;
253
254	sta->sta_state = IEEE80211_STA_NONE;
255
256	do_posix_clock_monotonic_gettime(&uptime);
257	sta->last_connected = uptime.tv_sec;
258	ewma_init(&sta->avg_signal, 1024, 8);
259
260	if (sta_prepare_rate_control(local, sta, gfp)) {
261		kfree(sta);
262		return NULL;
263	}
264
265	for (i = 0; i < STA_TID_NUM; i++) {
266		/*
267		 * timer_to_tid must be initialized with identity mapping
268		 * to enable session_timer's data differentiation. See
269		 * sta_rx_agg_session_timer_expired for usage.
270		 */
271		sta->timer_to_tid[i] = i;
272	}
273	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
274		skb_queue_head_init(&sta->ps_tx_buf[i]);
275		skb_queue_head_init(&sta->tx_filtered[i]);
276	}
277
278	for (i = 0; i < NUM_RX_DATA_QUEUES; i++)
279		sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX);
280
281#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
282	wiphy_debug(local->hw.wiphy, "Allocated STA %pM\n", sta->sta.addr);
283#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
284
285#ifdef CONFIG_MAC80211_MESH
286	sta->plink_state = NL80211_PLINK_LISTEN;
287	init_timer(&sta->plink_timer);
288#endif
289
290	return sta;
291}
292
293static int sta_info_insert_check(struct sta_info *sta)
294{
295	struct ieee80211_sub_if_data *sdata = sta->sdata;
296
297	/*
298	 * Can't be a WARN_ON because it can be triggered through a race:
299	 * something inserts a STA (on one CPU) without holding the RTNL
300	 * and another CPU turns off the net device.
301	 */
302	if (unlikely(!ieee80211_sdata_running(sdata)))
303		return -ENETDOWN;
304
305	if (WARN_ON(ether_addr_equal(sta->sta.addr, sdata->vif.addr) ||
306		    is_multicast_ether_addr(sta->sta.addr)))
307		return -EINVAL;
308
309	return 0;
310}
311
312static int sta_info_insert_drv_state(struct ieee80211_local *local,
313				     struct ieee80211_sub_if_data *sdata,
314				     struct sta_info *sta)
315{
316	enum ieee80211_sta_state state;
317	int err = 0;
318
319	for (state = IEEE80211_STA_NOTEXIST; state < sta->sta_state; state++) {
320		err = drv_sta_state(local, sdata, sta, state, state + 1);
321		if (err)
322			break;
323	}
324
325	if (!err) {
326		/*
327		 * Drivers using legacy sta_add/sta_remove callbacks only
328		 * get uploaded set to true after sta_add is called.
329		 */
330		if (!local->ops->sta_add)
331			sta->uploaded = true;
332		return 0;
333	}
334
335	if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
336		pr_debug("%s: failed to move IBSS STA %pM to state %d (%d) - keeping it anyway\n",
337			 sdata->name, sta->sta.addr, state + 1, err);
338		err = 0;
339	}
340
341	/* unwind on error */
342	for (; state > IEEE80211_STA_NOTEXIST; state--)
343		WARN_ON(drv_sta_state(local, sdata, sta, state, state - 1));
344
345	return err;
346}
347
348/*
349 * should be called with sta_mtx locked
350 * this function replaces the mutex lock
351 * with a RCU lock
352 */
353static int sta_info_insert_finish(struct sta_info *sta) __acquires(RCU)
354{
355	struct ieee80211_local *local = sta->local;
356	struct ieee80211_sub_if_data *sdata = sta->sdata;
357	struct station_info sinfo;
358	int err = 0;
359
360	lockdep_assert_held(&local->sta_mtx);
361
362	/* check if STA exists already */
363	if (sta_info_get_bss(sdata, sta->sta.addr)) {
364		err = -EEXIST;
365		goto out_err;
366	}
367
368	/* notify driver */
369	err = sta_info_insert_drv_state(local, sdata, sta);
370	if (err)
371		goto out_err;
372
373	local->num_sta++;
374	local->sta_generation++;
375	smp_mb();
376
377	/* make the station visible */
378	sta_info_hash_add(local, sta);
379
380	list_add(&sta->list, &local->sta_list);
381
382	set_sta_flag(sta, WLAN_STA_INSERTED);
383
384	ieee80211_sta_debugfs_add(sta);
385	rate_control_add_sta_debugfs(sta);
386
387	memset(&sinfo, 0, sizeof(sinfo));
388	sinfo.filled = 0;
389	sinfo.generation = local->sta_generation;
390	cfg80211_new_sta(sdata->dev, sta->sta.addr, &sinfo, GFP_KERNEL);
391
392#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
393	wiphy_debug(local->hw.wiphy, "Inserted STA %pM\n", sta->sta.addr);
394#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
395
396	/* move reference to rcu-protected */
397	rcu_read_lock();
398	mutex_unlock(&local->sta_mtx);
399
400	if (ieee80211_vif_is_mesh(&sdata->vif))
401		mesh_accept_plinks_update(sdata);
402
403	return 0;
404 out_err:
405	mutex_unlock(&local->sta_mtx);
406	rcu_read_lock();
407	return err;
408}
409
410int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU)
411{
412	struct ieee80211_local *local = sta->local;
413	int err = 0;
414
415	might_sleep();
416
417	err = sta_info_insert_check(sta);
418	if (err) {
419		rcu_read_lock();
420		goto out_free;
421	}
422
423	mutex_lock(&local->sta_mtx);
424
425	err = sta_info_insert_finish(sta);
426	if (err)
427		goto out_free;
428
429	return 0;
430 out_free:
431	BUG_ON(!err);
432	sta_info_free(local, sta);
433	return err;
434}
435
436int sta_info_insert(struct sta_info *sta)
437{
438	int err = sta_info_insert_rcu(sta);
439
440	rcu_read_unlock();
441
442	return err;
443}
444
445static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid)
446{
447	/*
448	 * This format has been mandated by the IEEE specifications,
449	 * so this line may not be changed to use the __set_bit() format.
450	 */
451	bss->tim[aid / 8] |= (1 << (aid % 8));
452}
453
454static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid)
455{
456	/*
457	 * This format has been mandated by the IEEE specifications,
458	 * so this line may not be changed to use the __clear_bit() format.
459	 */
460	bss->tim[aid / 8] &= ~(1 << (aid % 8));
461}
462
463static unsigned long ieee80211_tids_for_ac(int ac)
464{
465	/* If we ever support TIDs > 7, this obviously needs to be adjusted */
466	switch (ac) {
467	case IEEE80211_AC_VO:
468		return BIT(6) | BIT(7);
469	case IEEE80211_AC_VI:
470		return BIT(4) | BIT(5);
471	case IEEE80211_AC_BE:
472		return BIT(0) | BIT(3);
473	case IEEE80211_AC_BK:
474		return BIT(1) | BIT(2);
475	default:
476		WARN_ON(1);
477		return 0;
478	}
479}
480
481void sta_info_recalc_tim(struct sta_info *sta)
482{
483	struct ieee80211_local *local = sta->local;
484	struct ieee80211_if_ap *bss = sta->sdata->bss;
485	unsigned long flags;
486	bool indicate_tim = false;
487	u8 ignore_for_tim = sta->sta.uapsd_queues;
488	int ac;
489
490	if (WARN_ON_ONCE(!sta->sdata->bss))
491		return;
492
493	/* No need to do anything if the driver does all */
494	if (local->hw.flags & IEEE80211_HW_AP_LINK_PS)
495		return;
496
497	if (sta->dead)
498		goto done;
499
500	/*
501	 * If all ACs are delivery-enabled then we should build
502	 * the TIM bit for all ACs anyway; if only some are then
503	 * we ignore those and build the TIM bit using only the
504	 * non-enabled ones.
505	 */
506	if (ignore_for_tim == BIT(IEEE80211_NUM_ACS) - 1)
507		ignore_for_tim = 0;
508
509	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
510		unsigned long tids;
511
512		if (ignore_for_tim & BIT(ac))
513			continue;
514
515		indicate_tim |= !skb_queue_empty(&sta->tx_filtered[ac]) ||
516				!skb_queue_empty(&sta->ps_tx_buf[ac]);
517		if (indicate_tim)
518			break;
519
520		tids = ieee80211_tids_for_ac(ac);
521
522		indicate_tim |=
523			sta->driver_buffered_tids & tids;
524	}
525
526 done:
527	spin_lock_irqsave(&local->tim_lock, flags);
528
529	if (indicate_tim)
530		__bss_tim_set(bss, sta->sta.aid);
531	else
532		__bss_tim_clear(bss, sta->sta.aid);
533
534	if (local->ops->set_tim) {
535		local->tim_in_locked_section = true;
536		drv_set_tim(local, &sta->sta, indicate_tim);
537		local->tim_in_locked_section = false;
538	}
539
540	spin_unlock_irqrestore(&local->tim_lock, flags);
541}
542
543static bool sta_info_buffer_expired(struct sta_info *sta, struct sk_buff *skb)
544{
545	struct ieee80211_tx_info *info;
546	int timeout;
547
548	if (!skb)
549		return false;
550
551	info = IEEE80211_SKB_CB(skb);
552
553	/* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */
554	timeout = (sta->listen_interval *
555		   sta->sdata->vif.bss_conf.beacon_int *
556		   32 / 15625) * HZ;
557	if (timeout < STA_TX_BUFFER_EXPIRE)
558		timeout = STA_TX_BUFFER_EXPIRE;
559	return time_after(jiffies, info->control.jiffies + timeout);
560}
561
562
563static bool sta_info_cleanup_expire_buffered_ac(struct ieee80211_local *local,
564						struct sta_info *sta, int ac)
565{
566	unsigned long flags;
567	struct sk_buff *skb;
568
569	/*
570	 * First check for frames that should expire on the filtered
571	 * queue. Frames here were rejected by the driver and are on
572	 * a separate queue to avoid reordering with normal PS-buffered
573	 * frames. They also aren't accounted for right now in the
574	 * total_ps_buffered counter.
575	 */
576	for (;;) {
577		spin_lock_irqsave(&sta->tx_filtered[ac].lock, flags);
578		skb = skb_peek(&sta->tx_filtered[ac]);
579		if (sta_info_buffer_expired(sta, skb))
580			skb = __skb_dequeue(&sta->tx_filtered[ac]);
581		else
582			skb = NULL;
583		spin_unlock_irqrestore(&sta->tx_filtered[ac].lock, flags);
584
585		/*
586		 * Frames are queued in order, so if this one
587		 * hasn't expired yet we can stop testing. If
588		 * we actually reached the end of the queue we
589		 * also need to stop, of course.
590		 */
591		if (!skb)
592			break;
593		dev_kfree_skb(skb);
594	}
595
596	/*
597	 * Now also check the normal PS-buffered queue, this will
598	 * only find something if the filtered queue was emptied
599	 * since the filtered frames are all before the normal PS
600	 * buffered frames.
601	 */
602	for (;;) {
603		spin_lock_irqsave(&sta->ps_tx_buf[ac].lock, flags);
604		skb = skb_peek(&sta->ps_tx_buf[ac]);
605		if (sta_info_buffer_expired(sta, skb))
606			skb = __skb_dequeue(&sta->ps_tx_buf[ac]);
607		else
608			skb = NULL;
609		spin_unlock_irqrestore(&sta->ps_tx_buf[ac].lock, flags);
610
611		/*
612		 * frames are queued in order, so if this one
613		 * hasn't expired yet (or we reached the end of
614		 * the queue) we can stop testing
615		 */
616		if (!skb)
617			break;
618
619		local->total_ps_buffered--;
620#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
621		pr_debug("Buffered frame expired (STA %pM)\n", sta->sta.addr);
622#endif
623		dev_kfree_skb(skb);
624	}
625
626	/*
627	 * Finally, recalculate the TIM bit for this station -- it might
628	 * now be clear because the station was too slow to retrieve its
629	 * frames.
630	 */
631	sta_info_recalc_tim(sta);
632
633	/*
634	 * Return whether there are any frames still buffered, this is
635	 * used to check whether the cleanup timer still needs to run,
636	 * if there are no frames we don't need to rearm the timer.
637	 */
638	return !(skb_queue_empty(&sta->ps_tx_buf[ac]) &&
639		 skb_queue_empty(&sta->tx_filtered[ac]));
640}
641
642static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
643					     struct sta_info *sta)
644{
645	bool have_buffered = false;
646	int ac;
647
648	/* This is only necessary for stations on BSS interfaces */
649	if (!sta->sdata->bss)
650		return false;
651
652	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
653		have_buffered |=
654			sta_info_cleanup_expire_buffered_ac(local, sta, ac);
655
656	return have_buffered;
657}
658
659int __must_check __sta_info_destroy(struct sta_info *sta)
660{
661	struct ieee80211_local *local;
662	struct ieee80211_sub_if_data *sdata;
663	int ret, i, ac;
664	struct tid_ampdu_tx *tid_tx;
665
666	might_sleep();
667
668	if (!sta)
669		return -ENOENT;
670
671	local = sta->local;
672	sdata = sta->sdata;
673
674	lockdep_assert_held(&local->sta_mtx);
675
676	/*
677	 * Before removing the station from the driver and
678	 * rate control, it might still start new aggregation
679	 * sessions -- block that to make sure the tear-down
680	 * will be sufficient.
681	 */
682	set_sta_flag(sta, WLAN_STA_BLOCK_BA);
683	ieee80211_sta_tear_down_BA_sessions(sta, true);
684
685	ret = sta_info_hash_del(local, sta);
686	if (ret)
687		return ret;
688
689	list_del(&sta->list);
690
691	mutex_lock(&local->key_mtx);
692	for (i = 0; i < NUM_DEFAULT_KEYS; i++)
693		__ieee80211_key_free(key_mtx_dereference(local, sta->gtk[i]));
694	if (sta->ptk)
695		__ieee80211_key_free(key_mtx_dereference(local, sta->ptk));
696	mutex_unlock(&local->key_mtx);
697
698	sta->dead = true;
699
700	local->num_sta--;
701	local->sta_generation++;
702
703	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
704		RCU_INIT_POINTER(sdata->u.vlan.sta, NULL);
705
706	while (sta->sta_state > IEEE80211_STA_NONE) {
707		ret = sta_info_move_state(sta, sta->sta_state - 1);
708		if (ret) {
709			WARN_ON_ONCE(1);
710			break;
711		}
712	}
713
714	if (sta->uploaded) {
715		ret = drv_sta_state(local, sdata, sta, IEEE80211_STA_NONE,
716				    IEEE80211_STA_NOTEXIST);
717		WARN_ON_ONCE(ret != 0);
718	}
719
720	/*
721	 * At this point, after we wait for an RCU grace period,
722	 * neither mac80211 nor the driver can reference this
723	 * sta struct any more except by still existing timers
724	 * associated with this station that we clean up below.
725	 */
726	synchronize_rcu();
727
728	if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
729		BUG_ON(!sdata->bss);
730
731		clear_sta_flag(sta, WLAN_STA_PS_STA);
732
733		atomic_dec(&sdata->bss->num_sta_ps);
734		sta_info_recalc_tim(sta);
735	}
736
737	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
738		local->total_ps_buffered -= skb_queue_len(&sta->ps_tx_buf[ac]);
739		__skb_queue_purge(&sta->ps_tx_buf[ac]);
740		__skb_queue_purge(&sta->tx_filtered[ac]);
741	}
742
743#ifdef CONFIG_MAC80211_MESH
744	if (ieee80211_vif_is_mesh(&sdata->vif))
745		mesh_accept_plinks_update(sdata);
746#endif
747
748#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
749	wiphy_debug(local->hw.wiphy, "Removed STA %pM\n", sta->sta.addr);
750#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
751	cancel_work_sync(&sta->drv_unblock_wk);
752
753	cfg80211_del_sta(sdata->dev, sta->sta.addr, GFP_KERNEL);
754
755	rate_control_remove_sta_debugfs(sta);
756	ieee80211_sta_debugfs_remove(sta);
757
758#ifdef CONFIG_MAC80211_MESH
759	if (ieee80211_vif_is_mesh(&sta->sdata->vif)) {
760		mesh_plink_deactivate(sta);
761		del_timer_sync(&sta->plink_timer);
762	}
763#endif
764
765	/*
766	 * Destroy aggregation state here. It would be nice to wait for the
767	 * driver to finish aggregation stop and then clean up, but for now
768	 * drivers have to handle aggregation stop being requested, followed
769	 * directly by station destruction.
770	 */
771	for (i = 0; i < STA_TID_NUM; i++) {
772		tid_tx = rcu_dereference_raw(sta->ampdu_mlme.tid_tx[i]);
773		if (!tid_tx)
774			continue;
775		__skb_queue_purge(&tid_tx->pending);
776		kfree(tid_tx);
777	}
778
779	sta_info_free(local, sta);
780
781	return 0;
782}
783
784int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata, const u8 *addr)
785{
786	struct sta_info *sta;
787	int ret;
788
789	mutex_lock(&sdata->local->sta_mtx);
790	sta = sta_info_get(sdata, addr);
791	ret = __sta_info_destroy(sta);
792	mutex_unlock(&sdata->local->sta_mtx);
793
794	return ret;
795}
796
797int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata,
798			      const u8 *addr)
799{
800	struct sta_info *sta;
801	int ret;
802
803	mutex_lock(&sdata->local->sta_mtx);
804	sta = sta_info_get_bss(sdata, addr);
805	ret = __sta_info_destroy(sta);
806	mutex_unlock(&sdata->local->sta_mtx);
807
808	return ret;
809}
810
811static void sta_info_cleanup(unsigned long data)
812{
813	struct ieee80211_local *local = (struct ieee80211_local *) data;
814	struct sta_info *sta;
815	bool timer_needed = false;
816
817	rcu_read_lock();
818	list_for_each_entry_rcu(sta, &local->sta_list, list)
819		if (sta_info_cleanup_expire_buffered(local, sta))
820			timer_needed = true;
821	rcu_read_unlock();
822
823	if (local->quiescing)
824		return;
825
826	if (!timer_needed)
827		return;
828
829	mod_timer(&local->sta_cleanup,
830		  round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL));
831}
832
833void sta_info_init(struct ieee80211_local *local)
834{
835	spin_lock_init(&local->tim_lock);
836	mutex_init(&local->sta_mtx);
837	INIT_LIST_HEAD(&local->sta_list);
838
839	setup_timer(&local->sta_cleanup, sta_info_cleanup,
840		    (unsigned long)local);
841}
842
843void sta_info_stop(struct ieee80211_local *local)
844{
845	del_timer(&local->sta_cleanup);
846	sta_info_flush(local, NULL);
847}
848
849/**
850 * sta_info_flush - flush matching STA entries from the STA table
851 *
852 * Returns the number of removed STA entries.
853 *
854 * @local: local interface data
855 * @sdata: matching rule for the net device (sta->dev) or %NULL to match all STAs
856 */
857int sta_info_flush(struct ieee80211_local *local,
858		   struct ieee80211_sub_if_data *sdata)
859{
860	struct sta_info *sta, *tmp;
861	int ret = 0;
862
863	might_sleep();
864
865	mutex_lock(&local->sta_mtx);
866	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
867		if (!sdata || sdata == sta->sdata) {
868			WARN_ON(__sta_info_destroy(sta));
869			ret++;
870		}
871	}
872	mutex_unlock(&local->sta_mtx);
873
874	return ret;
875}
876
877void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata,
878			  unsigned long exp_time)
879{
880	struct ieee80211_local *local = sdata->local;
881	struct sta_info *sta, *tmp;
882
883	mutex_lock(&local->sta_mtx);
884
885	list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
886		if (sdata != sta->sdata)
887			continue;
888
889		if (time_after(jiffies, sta->last_rx + exp_time)) {
890			ibss_vdbg("%s: expiring inactive STA %pM\n",
891				  sdata->name, sta->sta.addr);
892			WARN_ON(__sta_info_destroy(sta));
893		}
894	}
895
896	mutex_unlock(&local->sta_mtx);
897}
898
899struct ieee80211_sta *ieee80211_find_sta_by_ifaddr(struct ieee80211_hw *hw,
900					       const u8 *addr,
901					       const u8 *localaddr)
902{
903	struct sta_info *sta, *nxt;
904
905	/*
906	 * Just return a random station if localaddr is NULL
907	 * ... first in list.
908	 */
909	for_each_sta_info(hw_to_local(hw), addr, sta, nxt) {
910		if (localaddr &&
911		    !ether_addr_equal(sta->sdata->vif.addr, localaddr))
912			continue;
913		if (!sta->uploaded)
914			return NULL;
915		return &sta->sta;
916	}
917
918	return NULL;
919}
920EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_ifaddr);
921
922struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_vif *vif,
923					 const u8 *addr)
924{
925	struct sta_info *sta;
926
927	if (!vif)
928		return NULL;
929
930	sta = sta_info_get_bss(vif_to_sdata(vif), addr);
931	if (!sta)
932		return NULL;
933
934	if (!sta->uploaded)
935		return NULL;
936
937	return &sta->sta;
938}
939EXPORT_SYMBOL(ieee80211_find_sta);
940
941static void clear_sta_ps_flags(void *_sta)
942{
943	struct sta_info *sta = _sta;
944	struct ieee80211_sub_if_data *sdata = sta->sdata;
945
946	clear_sta_flag(sta, WLAN_STA_PS_DRIVER);
947	if (test_and_clear_sta_flag(sta, WLAN_STA_PS_STA))
948		atomic_dec(&sdata->bss->num_sta_ps);
949}
950
951/* powersave support code */
952void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta)
953{
954	struct ieee80211_sub_if_data *sdata = sta->sdata;
955	struct ieee80211_local *local = sdata->local;
956	struct sk_buff_head pending;
957	int filtered = 0, buffered = 0, ac;
958
959	clear_sta_flag(sta, WLAN_STA_SP);
960
961	BUILD_BUG_ON(BITS_TO_LONGS(STA_TID_NUM) > 1);
962	sta->driver_buffered_tids = 0;
963
964	if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
965		drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta);
966
967	skb_queue_head_init(&pending);
968
969	/* Send all buffered frames to the station */
970	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
971		int count = skb_queue_len(&pending), tmp;
972
973		skb_queue_splice_tail_init(&sta->tx_filtered[ac], &pending);
974		tmp = skb_queue_len(&pending);
975		filtered += tmp - count;
976		count = tmp;
977
978		skb_queue_splice_tail_init(&sta->ps_tx_buf[ac], &pending);
979		tmp = skb_queue_len(&pending);
980		buffered += tmp - count;
981	}
982
983	ieee80211_add_pending_skbs_fn(local, &pending, clear_sta_ps_flags, sta);
984
985	local->total_ps_buffered -= buffered;
986
987	sta_info_recalc_tim(sta);
988
989#ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
990	pr_debug("%s: STA %pM aid %d sending %d filtered/%d PS frames since STA not sleeping anymore\n",
991		 sdata->name, sta->sta.addr, sta->sta.aid, filtered, buffered);
992#endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
993}
994
995static void ieee80211_send_null_response(struct ieee80211_sub_if_data *sdata,
996					 struct sta_info *sta, int tid,
997					 enum ieee80211_frame_release_type reason)
998{
999	struct ieee80211_local *local = sdata->local;
1000	struct ieee80211_qos_hdr *nullfunc;
1001	struct sk_buff *skb;
1002	int size = sizeof(*nullfunc);
1003	__le16 fc;
1004	bool qos = test_sta_flag(sta, WLAN_STA_WME);
1005	struct ieee80211_tx_info *info;
1006
1007	if (qos) {
1008		fc = cpu_to_le16(IEEE80211_FTYPE_DATA |
1009				 IEEE80211_STYPE_QOS_NULLFUNC |
1010				 IEEE80211_FCTL_FROMDS);
1011	} else {
1012		size -= 2;
1013		fc = cpu_to_le16(IEEE80211_FTYPE_DATA |
1014				 IEEE80211_STYPE_NULLFUNC |
1015				 IEEE80211_FCTL_FROMDS);
1016	}
1017
1018	skb = dev_alloc_skb(local->hw.extra_tx_headroom + size);
1019	if (!skb)
1020		return;
1021
1022	skb_reserve(skb, local->hw.extra_tx_headroom);
1023
1024	nullfunc = (void *) skb_put(skb, size);
1025	nullfunc->frame_control = fc;
1026	nullfunc->duration_id = 0;
1027	memcpy(nullfunc->addr1, sta->sta.addr, ETH_ALEN);
1028	memcpy(nullfunc->addr2, sdata->vif.addr, ETH_ALEN);
1029	memcpy(nullfunc->addr3, sdata->vif.addr, ETH_ALEN);
1030
1031	skb->priority = tid;
1032	skb_set_queue_mapping(skb, ieee802_1d_to_ac[tid]);
1033	if (qos) {
1034		nullfunc->qos_ctrl = cpu_to_le16(tid);
1035
1036		if (reason == IEEE80211_FRAME_RELEASE_UAPSD)
1037			nullfunc->qos_ctrl |=
1038				cpu_to_le16(IEEE80211_QOS_CTL_EOSP);
1039	}
1040
1041	info = IEEE80211_SKB_CB(skb);
1042
1043	/*
1044	 * Tell TX path to send this frame even though the
1045	 * STA may still remain is PS mode after this frame
1046	 * exchange. Also set EOSP to indicate this packet
1047	 * ends the poll/service period.
1048	 */
1049	info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER |
1050		       IEEE80211_TX_STATUS_EOSP |
1051		       IEEE80211_TX_CTL_REQ_TX_STATUS;
1052
1053	drv_allow_buffered_frames(local, sta, BIT(tid), 1, reason, false);
1054
1055	ieee80211_xmit(sdata, skb);
1056}
1057
1058static void
1059ieee80211_sta_ps_deliver_response(struct sta_info *sta,
1060				  int n_frames, u8 ignored_acs,
1061				  enum ieee80211_frame_release_type reason)
1062{
1063	struct ieee80211_sub_if_data *sdata = sta->sdata;
1064	struct ieee80211_local *local = sdata->local;
1065	bool found = false;
1066	bool more_data = false;
1067	int ac;
1068	unsigned long driver_release_tids = 0;
1069	struct sk_buff_head frames;
1070
1071	/* Service or PS-Poll period starts */
1072	set_sta_flag(sta, WLAN_STA_SP);
1073
1074	__skb_queue_head_init(&frames);
1075
1076	/*
1077	 * Get response frame(s) and more data bit for it.
1078	 */
1079	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
1080		unsigned long tids;
1081
1082		if (ignored_acs & BIT(ac))
1083			continue;
1084
1085		tids = ieee80211_tids_for_ac(ac);
1086
1087		if (!found) {
1088			driver_release_tids = sta->driver_buffered_tids & tids;
1089			if (driver_release_tids) {
1090				found = true;
1091			} else {
1092				struct sk_buff *skb;
1093
1094				while (n_frames > 0) {
1095					skb = skb_dequeue(&sta->tx_filtered[ac]);
1096					if (!skb) {
1097						skb = skb_dequeue(
1098							&sta->ps_tx_buf[ac]);
1099						if (skb)
1100							local->total_ps_buffered--;
1101					}
1102					if (!skb)
1103						break;
1104					n_frames--;
1105					found = true;
1106					__skb_queue_tail(&frames, skb);
1107				}
1108			}
1109
1110			/*
1111			 * If the driver has data on more than one TID then
1112			 * certainly there's more data if we release just a
1113			 * single frame now (from a single TID).
1114			 */
1115			if (reason == IEEE80211_FRAME_RELEASE_PSPOLL &&
1116			    hweight16(driver_release_tids) > 1) {
1117				more_data = true;
1118				driver_release_tids =
1119					BIT(ffs(driver_release_tids) - 1);
1120				break;
1121			}
1122		}
1123
1124		if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
1125		    !skb_queue_empty(&sta->ps_tx_buf[ac])) {
1126			more_data = true;
1127			break;
1128		}
1129	}
1130
1131	if (!found) {
1132		int tid;
1133
1134		/*
1135		 * For PS-Poll, this can only happen due to a race condition
1136		 * when we set the TIM bit and the station notices it, but
1137		 * before it can poll for the frame we expire it.
1138		 *
1139		 * For uAPSD, this is said in the standard (11.2.1.5 h):
1140		 *	At each unscheduled SP for a non-AP STA, the AP shall
1141		 *	attempt to transmit at least one MSDU or MMPDU, but no
1142		 *	more than the value specified in the Max SP Length field
1143		 *	in the QoS Capability element from delivery-enabled ACs,
1144		 *	that are destined for the non-AP STA.
1145		 *
1146		 * Since we have no other MSDU/MMPDU, transmit a QoS null frame.
1147		 */
1148
1149		/* This will evaluate to 1, 3, 5 or 7. */
1150		tid = 7 - ((ffs(~ignored_acs) - 1) << 1);
1151
1152		ieee80211_send_null_response(sdata, sta, tid, reason);
1153		return;
1154	}
1155
1156	if (!driver_release_tids) {
1157		struct sk_buff_head pending;
1158		struct sk_buff *skb;
1159		int num = 0;
1160		u16 tids = 0;
1161
1162		skb_queue_head_init(&pending);
1163
1164		while ((skb = __skb_dequeue(&frames))) {
1165			struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1166			struct ieee80211_hdr *hdr = (void *) skb->data;
1167			u8 *qoshdr = NULL;
1168
1169			num++;
1170
1171			/*
1172			 * Tell TX path to send this frame even though the
1173			 * STA may still remain is PS mode after this frame
1174			 * exchange.
1175			 */
1176			info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
1177
1178			/*
1179			 * Use MoreData flag to indicate whether there are
1180			 * more buffered frames for this STA
1181			 */
1182			if (more_data || !skb_queue_empty(&frames))
1183				hdr->frame_control |=
1184					cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1185			else
1186				hdr->frame_control &=
1187					cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1188
1189			if (ieee80211_is_data_qos(hdr->frame_control) ||
1190			    ieee80211_is_qos_nullfunc(hdr->frame_control))
1191				qoshdr = ieee80211_get_qos_ctl(hdr);
1192
1193			/* end service period after last frame */
1194			if (skb_queue_empty(&frames)) {
1195				if (reason == IEEE80211_FRAME_RELEASE_UAPSD &&
1196				    qoshdr)
1197					*qoshdr |= IEEE80211_QOS_CTL_EOSP;
1198
1199				info->flags |= IEEE80211_TX_STATUS_EOSP |
1200					       IEEE80211_TX_CTL_REQ_TX_STATUS;
1201			}
1202
1203			if (qoshdr)
1204				tids |= BIT(*qoshdr & IEEE80211_QOS_CTL_TID_MASK);
1205			else
1206				tids |= BIT(0);
1207
1208			__skb_queue_tail(&pending, skb);
1209		}
1210
1211		drv_allow_buffered_frames(local, sta, tids, num,
1212					  reason, more_data);
1213
1214		ieee80211_add_pending_skbs(local, &pending);
1215
1216		sta_info_recalc_tim(sta);
1217	} else {
1218		/*
1219		 * We need to release a frame that is buffered somewhere in the
1220		 * driver ... it'll have to handle that.
1221		 * Note that, as per the comment above, it'll also have to see
1222		 * if there is more than just one frame on the specific TID that
1223		 * we're releasing from, and it needs to set the more-data bit
1224		 * accordingly if we tell it that there's no more data. If we do
1225		 * tell it there's more data, then of course the more-data bit
1226		 * needs to be set anyway.
1227		 */
1228		drv_release_buffered_frames(local, sta, driver_release_tids,
1229					    n_frames, reason, more_data);
1230
1231		/*
1232		 * Note that we don't recalculate the TIM bit here as it would
1233		 * most likely have no effect at all unless the driver told us
1234		 * that the TID became empty before returning here from the
1235		 * release function.
1236		 * Either way, however, when the driver tells us that the TID
1237		 * became empty we'll do the TIM recalculation.
1238		 */
1239	}
1240}
1241
1242void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta)
1243{
1244	u8 ignore_for_response = sta->sta.uapsd_queues;
1245
1246	/*
1247	 * If all ACs are delivery-enabled then we should reply
1248	 * from any of them, if only some are enabled we reply
1249	 * only from the non-enabled ones.
1250	 */
1251	if (ignore_for_response == BIT(IEEE80211_NUM_ACS) - 1)
1252		ignore_for_response = 0;
1253
1254	ieee80211_sta_ps_deliver_response(sta, 1, ignore_for_response,
1255					  IEEE80211_FRAME_RELEASE_PSPOLL);
1256}
1257
1258void ieee80211_sta_ps_deliver_uapsd(struct sta_info *sta)
1259{
1260	int n_frames = sta->sta.max_sp;
1261	u8 delivery_enabled = sta->sta.uapsd_queues;
1262
1263	/*
1264	 * If we ever grow support for TSPEC this might happen if
1265	 * the TSPEC update from hostapd comes in between a trigger
1266	 * frame setting WLAN_STA_UAPSD in the RX path and this
1267	 * actually getting called.
1268	 */
1269	if (!delivery_enabled)
1270		return;
1271
1272	switch (sta->sta.max_sp) {
1273	case 1:
1274		n_frames = 2;
1275		break;
1276	case 2:
1277		n_frames = 4;
1278		break;
1279	case 3:
1280		n_frames = 6;
1281		break;
1282	case 0:
1283		/* XXX: what is a good value? */
1284		n_frames = 8;
1285		break;
1286	}
1287
1288	ieee80211_sta_ps_deliver_response(sta, n_frames, ~delivery_enabled,
1289					  IEEE80211_FRAME_RELEASE_UAPSD);
1290}
1291
1292void ieee80211_sta_block_awake(struct ieee80211_hw *hw,
1293			       struct ieee80211_sta *pubsta, bool block)
1294{
1295	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1296
1297	trace_api_sta_block_awake(sta->local, pubsta, block);
1298
1299	if (block)
1300		set_sta_flag(sta, WLAN_STA_PS_DRIVER);
1301	else if (test_sta_flag(sta, WLAN_STA_PS_DRIVER))
1302		ieee80211_queue_work(hw, &sta->drv_unblock_wk);
1303}
1304EXPORT_SYMBOL(ieee80211_sta_block_awake);
1305
1306void ieee80211_sta_eosp_irqsafe(struct ieee80211_sta *pubsta)
1307{
1308	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1309	struct ieee80211_local *local = sta->local;
1310	struct sk_buff *skb;
1311	struct skb_eosp_msg_data *data;
1312
1313	trace_api_eosp(local, pubsta);
1314
1315	skb = alloc_skb(0, GFP_ATOMIC);
1316	if (!skb) {
1317		/* too bad ... but race is better than loss */
1318		clear_sta_flag(sta, WLAN_STA_SP);
1319		return;
1320	}
1321
1322	data = (void *)skb->cb;
1323	memcpy(data->sta, pubsta->addr, ETH_ALEN);
1324	memcpy(data->iface, sta->sdata->vif.addr, ETH_ALEN);
1325	skb->pkt_type = IEEE80211_EOSP_MSG;
1326	skb_queue_tail(&local->skb_queue, skb);
1327	tasklet_schedule(&local->tasklet);
1328}
1329EXPORT_SYMBOL(ieee80211_sta_eosp_irqsafe);
1330
1331void ieee80211_sta_set_buffered(struct ieee80211_sta *pubsta,
1332				u8 tid, bool buffered)
1333{
1334	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1335
1336	if (WARN_ON(tid >= STA_TID_NUM))
1337		return;
1338
1339	if (buffered)
1340		set_bit(tid, &sta->driver_buffered_tids);
1341	else
1342		clear_bit(tid, &sta->driver_buffered_tids);
1343
1344	sta_info_recalc_tim(sta);
1345}
1346EXPORT_SYMBOL(ieee80211_sta_set_buffered);
1347
1348int sta_info_move_state(struct sta_info *sta,
1349			enum ieee80211_sta_state new_state)
1350{
1351	might_sleep();
1352
1353	if (sta->sta_state == new_state)
1354		return 0;
1355
1356	/* check allowed transitions first */
1357
1358	switch (new_state) {
1359	case IEEE80211_STA_NONE:
1360		if (sta->sta_state != IEEE80211_STA_AUTH)
1361			return -EINVAL;
1362		break;
1363	case IEEE80211_STA_AUTH:
1364		if (sta->sta_state != IEEE80211_STA_NONE &&
1365		    sta->sta_state != IEEE80211_STA_ASSOC)
1366			return -EINVAL;
1367		break;
1368	case IEEE80211_STA_ASSOC:
1369		if (sta->sta_state != IEEE80211_STA_AUTH &&
1370		    sta->sta_state != IEEE80211_STA_AUTHORIZED)
1371			return -EINVAL;
1372		break;
1373	case IEEE80211_STA_AUTHORIZED:
1374		if (sta->sta_state != IEEE80211_STA_ASSOC)
1375			return -EINVAL;
1376		break;
1377	default:
1378		WARN(1, "invalid state %d", new_state);
1379		return -EINVAL;
1380	}
1381
1382#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
1383	pr_debug("%s: moving STA %pM to state %d\n",
1384		 sta->sdata->name, sta->sta.addr, new_state);
1385#endif
1386
1387	/*
1388	 * notify the driver before the actual changes so it can
1389	 * fail the transition
1390	 */
1391	if (test_sta_flag(sta, WLAN_STA_INSERTED)) {
1392		int err = drv_sta_state(sta->local, sta->sdata, sta,
1393					sta->sta_state, new_state);
1394		if (err)
1395			return err;
1396	}
1397
1398	/* reflect the change in all state variables */
1399
1400	switch (new_state) {
1401	case IEEE80211_STA_NONE:
1402		if (sta->sta_state == IEEE80211_STA_AUTH)
1403			clear_bit(WLAN_STA_AUTH, &sta->_flags);
1404		break;
1405	case IEEE80211_STA_AUTH:
1406		if (sta->sta_state == IEEE80211_STA_NONE)
1407			set_bit(WLAN_STA_AUTH, &sta->_flags);
1408		else if (sta->sta_state == IEEE80211_STA_ASSOC)
1409			clear_bit(WLAN_STA_ASSOC, &sta->_flags);
1410		break;
1411	case IEEE80211_STA_ASSOC:
1412		if (sta->sta_state == IEEE80211_STA_AUTH) {
1413			set_bit(WLAN_STA_ASSOC, &sta->_flags);
1414		} else if (sta->sta_state == IEEE80211_STA_AUTHORIZED) {
1415			if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1416			    (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1417			     !sta->sdata->u.vlan.sta))
1418				atomic_dec(&sta->sdata->bss->num_mcast_sta);
1419			clear_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
1420		}
1421		break;
1422	case IEEE80211_STA_AUTHORIZED:
1423		if (sta->sta_state == IEEE80211_STA_ASSOC) {
1424			if (sta->sdata->vif.type == NL80211_IFTYPE_AP ||
1425			    (sta->sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
1426			     !sta->sdata->u.vlan.sta))
1427				atomic_inc(&sta->sdata->bss->num_mcast_sta);
1428			set_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
1429		}
1430		break;
1431	default:
1432		break;
1433	}
1434
1435	sta->sta_state = new_state;
1436
1437	return 0;
1438}
1439