mac80211: split PS buffers into ACs
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / mac80211 / sta_info.c
blob4d85672f0b8f1f56cf6cb7cceb32bddedb1a177d
1 /*
2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
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 */
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/netdevice.h>
13 #include <linux/types.h>
14 #include <linux/slab.h>
15 #include <linux/skbuff.h>
16 #include <linux/if_arp.h>
17 #include <linux/timer.h>
18 #include <linux/rtnetlink.h>
20 #include <net/mac80211.h>
21 #include "ieee80211_i.h"
22 #include "driver-ops.h"
23 #include "rate.h"
24 #include "sta_info.h"
25 #include "debugfs_sta.h"
26 #include "mesh.h"
28 /**
29 * DOC: STA information lifetime rules
31 * STA info structures (&struct sta_info) are managed in a hash table
32 * for faster lookup and a list for iteration. They are managed using
33 * RCU, i.e. access to the list and hash table is protected by RCU.
35 * Upon allocating a STA info structure with sta_info_alloc(), the caller
36 * owns that structure. It must then insert it into the hash table using
37 * either sta_info_insert() or sta_info_insert_rcu(); only in the latter
38 * case (which acquires an rcu read section but must not be called from
39 * within one) will the pointer still be valid after the call. Note that
40 * the caller may not do much with the STA info before inserting it, in
41 * particular, it may not start any mesh peer link management or add
42 * encryption keys.
44 * When the insertion fails (sta_info_insert()) returns non-zero), the
45 * structure will have been freed by sta_info_insert()!
47 * Station entries are added by mac80211 when you establish a link with a
48 * peer. This means different things for the different type of interfaces
49 * we support. For a regular station this mean we add the AP sta when we
50 * receive an association response from the AP. For IBSS this occurs when
51 * get to know about a peer on the same IBSS. For WDS we add the sta for
52 * the peer immediately upon device open. When using AP mode we add stations
53 * for each respective station upon request from userspace through nl80211.
55 * In order to remove a STA info structure, various sta_info_destroy_*()
56 * calls are available.
58 * There is no concept of ownership on a STA entry, each structure is
59 * owned by the global hash table/list until it is removed. All users of
60 * the structure need to be RCU protected so that the structure won't be
61 * freed before they are done using it.
64 /* Caller must hold local->sta_lock */
65 static int sta_info_hash_del(struct ieee80211_local *local,
66 struct sta_info *sta)
68 struct sta_info *s;
70 s = rcu_dereference_protected(local->sta_hash[STA_HASH(sta->sta.addr)],
71 lockdep_is_held(&local->sta_lock));
72 if (!s)
73 return -ENOENT;
74 if (s == sta) {
75 rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)],
76 s->hnext);
77 return 0;
80 while (rcu_access_pointer(s->hnext) &&
81 rcu_access_pointer(s->hnext) != sta)
82 s = rcu_dereference_protected(s->hnext,
83 lockdep_is_held(&local->sta_lock));
84 if (rcu_access_pointer(s->hnext)) {
85 rcu_assign_pointer(s->hnext, sta->hnext);
86 return 0;
89 return -ENOENT;
92 /* protected by RCU */
93 struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata,
94 const u8 *addr)
96 struct ieee80211_local *local = sdata->local;
97 struct sta_info *sta;
99 sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)],
100 lockdep_is_held(&local->sta_lock) ||
101 lockdep_is_held(&local->sta_mtx));
102 while (sta) {
103 if (sta->sdata == sdata && !sta->dummy &&
104 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0)
105 break;
106 sta = rcu_dereference_check(sta->hnext,
107 lockdep_is_held(&local->sta_lock) ||
108 lockdep_is_held(&local->sta_mtx));
110 return sta;
113 /* get a station info entry even if it is a dummy station*/
114 struct sta_info *sta_info_get_rx(struct ieee80211_sub_if_data *sdata,
115 const u8 *addr)
117 struct ieee80211_local *local = sdata->local;
118 struct sta_info *sta;
120 sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)],
121 lockdep_is_held(&local->sta_lock) ||
122 lockdep_is_held(&local->sta_mtx));
123 while (sta) {
124 if (sta->sdata == sdata &&
125 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0)
126 break;
127 sta = rcu_dereference_check(sta->hnext,
128 lockdep_is_held(&local->sta_lock) ||
129 lockdep_is_held(&local->sta_mtx));
131 return sta;
135 * Get sta info either from the specified interface
136 * or from one of its vlans
138 struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata,
139 const u8 *addr)
141 struct ieee80211_local *local = sdata->local;
142 struct sta_info *sta;
144 sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)],
145 lockdep_is_held(&local->sta_lock) ||
146 lockdep_is_held(&local->sta_mtx));
147 while (sta) {
148 if ((sta->sdata == sdata ||
149 (sta->sdata->bss && sta->sdata->bss == sdata->bss)) &&
150 !sta->dummy &&
151 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0)
152 break;
153 sta = rcu_dereference_check(sta->hnext,
154 lockdep_is_held(&local->sta_lock) ||
155 lockdep_is_held(&local->sta_mtx));
157 return sta;
161 * Get sta info either from the specified interface
162 * or from one of its vlans (including dummy stations)
164 struct sta_info *sta_info_get_bss_rx(struct ieee80211_sub_if_data *sdata,
165 const u8 *addr)
167 struct ieee80211_local *local = sdata->local;
168 struct sta_info *sta;
170 sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)],
171 lockdep_is_held(&local->sta_lock) ||
172 lockdep_is_held(&local->sta_mtx));
173 while (sta) {
174 if ((sta->sdata == sdata ||
175 (sta->sdata->bss && sta->sdata->bss == sdata->bss)) &&
176 memcmp(sta->sta.addr, addr, ETH_ALEN) == 0)
177 break;
178 sta = rcu_dereference_check(sta->hnext,
179 lockdep_is_held(&local->sta_lock) ||
180 lockdep_is_held(&local->sta_mtx));
182 return sta;
185 struct sta_info *sta_info_get_by_idx(struct ieee80211_sub_if_data *sdata,
186 int idx)
188 struct ieee80211_local *local = sdata->local;
189 struct sta_info *sta;
190 int i = 0;
192 list_for_each_entry_rcu(sta, &local->sta_list, list) {
193 if (sdata != sta->sdata)
194 continue;
195 if (i < idx) {
196 ++i;
197 continue;
199 return sta;
202 return NULL;
206 * __sta_info_free - internal STA free helper
208 * @local: pointer to the global information
209 * @sta: STA info to free
211 * This function must undo everything done by sta_info_alloc()
212 * that may happen before sta_info_insert().
214 static void __sta_info_free(struct ieee80211_local *local,
215 struct sta_info *sta)
217 if (sta->rate_ctrl) {
218 rate_control_free_sta(sta);
219 rate_control_put(sta->rate_ctrl);
222 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
223 wiphy_debug(local->hw.wiphy, "Destroyed STA %pM\n", sta->sta.addr);
224 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
226 kfree(sta);
229 /* Caller must hold local->sta_lock */
230 static void sta_info_hash_add(struct ieee80211_local *local,
231 struct sta_info *sta)
233 sta->hnext = local->sta_hash[STA_HASH(sta->sta.addr)];
234 rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], sta);
237 static void sta_unblock(struct work_struct *wk)
239 struct sta_info *sta;
241 sta = container_of(wk, struct sta_info, drv_unblock_wk);
243 if (sta->dead)
244 return;
246 if (!test_sta_flags(sta, WLAN_STA_PS_STA))
247 ieee80211_sta_ps_deliver_wakeup(sta);
248 else if (test_and_clear_sta_flags(sta, WLAN_STA_PSPOLL)) {
249 clear_sta_flags(sta, WLAN_STA_PS_DRIVER);
250 ieee80211_sta_ps_deliver_poll_response(sta);
251 } else
252 clear_sta_flags(sta, WLAN_STA_PS_DRIVER);
255 static int sta_prepare_rate_control(struct ieee80211_local *local,
256 struct sta_info *sta, gfp_t gfp)
258 if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL)
259 return 0;
261 sta->rate_ctrl = rate_control_get(local->rate_ctrl);
262 sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl,
263 &sta->sta, gfp);
264 if (!sta->rate_ctrl_priv) {
265 rate_control_put(sta->rate_ctrl);
266 return -ENOMEM;
269 return 0;
272 struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
273 u8 *addr, gfp_t gfp)
275 struct ieee80211_local *local = sdata->local;
276 struct sta_info *sta;
277 struct timespec uptime;
278 int i;
280 sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp);
281 if (!sta)
282 return NULL;
284 spin_lock_init(&sta->lock);
285 spin_lock_init(&sta->flaglock);
286 INIT_WORK(&sta->drv_unblock_wk, sta_unblock);
287 INIT_WORK(&sta->ampdu_mlme.work, ieee80211_ba_session_work);
288 mutex_init(&sta->ampdu_mlme.mtx);
290 memcpy(sta->sta.addr, addr, ETH_ALEN);
291 sta->local = local;
292 sta->sdata = sdata;
293 sta->last_rx = jiffies;
295 do_posix_clock_monotonic_gettime(&uptime);
296 sta->last_connected = uptime.tv_sec;
297 ewma_init(&sta->avg_signal, 1024, 8);
299 if (sta_prepare_rate_control(local, sta, gfp)) {
300 kfree(sta);
301 return NULL;
304 for (i = 0; i < STA_TID_NUM; i++) {
306 * timer_to_tid must be initialized with identity mapping
307 * to enable session_timer's data differentiation. See
308 * sta_rx_agg_session_timer_expired for usage.
310 sta->timer_to_tid[i] = i;
312 for (i = 0; i < IEEE80211_NUM_ACS; i++) {
313 skb_queue_head_init(&sta->ps_tx_buf[i]);
314 skb_queue_head_init(&sta->tx_filtered[i]);
317 for (i = 0; i < NUM_RX_DATA_QUEUES; i++)
318 sta->last_seq_ctrl[i] = cpu_to_le16(USHRT_MAX);
320 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
321 wiphy_debug(local->hw.wiphy, "Allocated STA %pM\n", sta->sta.addr);
322 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
324 #ifdef CONFIG_MAC80211_MESH
325 sta->plink_state = NL80211_PLINK_LISTEN;
326 init_timer(&sta->plink_timer);
327 #endif
329 return sta;
332 static int sta_info_finish_insert(struct sta_info *sta,
333 bool async, bool dummy_reinsert)
335 struct ieee80211_local *local = sta->local;
336 struct ieee80211_sub_if_data *sdata = sta->sdata;
337 struct station_info sinfo;
338 unsigned long flags;
339 int err = 0;
341 lockdep_assert_held(&local->sta_mtx);
343 if (!sta->dummy || dummy_reinsert) {
344 /* notify driver */
345 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
346 sdata = container_of(sdata->bss,
347 struct ieee80211_sub_if_data,
348 u.ap);
349 err = drv_sta_add(local, sdata, &sta->sta);
350 if (err) {
351 if (!async)
352 return err;
353 printk(KERN_DEBUG "%s: failed to add IBSS STA %pM to "
354 "driver (%d) - keeping it anyway.\n",
355 sdata->name, sta->sta.addr, err);
356 } else {
357 sta->uploaded = true;
358 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
359 if (async)
360 wiphy_debug(local->hw.wiphy,
361 "Finished adding IBSS STA %pM\n",
362 sta->sta.addr);
363 #endif
366 sdata = sta->sdata;
369 if (!dummy_reinsert) {
370 if (!async) {
371 local->num_sta++;
372 local->sta_generation++;
373 smp_mb();
375 /* make the station visible */
376 spin_lock_irqsave(&local->sta_lock, flags);
377 sta_info_hash_add(local, sta);
378 spin_unlock_irqrestore(&local->sta_lock, flags);
381 list_add(&sta->list, &local->sta_list);
382 } else {
383 sta->dummy = false;
386 if (!sta->dummy) {
387 ieee80211_sta_debugfs_add(sta);
388 rate_control_add_sta_debugfs(sta);
390 memset(&sinfo, 0, sizeof(sinfo));
391 sinfo.filled = 0;
392 sinfo.generation = local->sta_generation;
393 cfg80211_new_sta(sdata->dev, sta->sta.addr, &sinfo, GFP_KERNEL);
396 return 0;
399 static void sta_info_finish_pending(struct ieee80211_local *local)
401 struct sta_info *sta;
402 unsigned long flags;
404 spin_lock_irqsave(&local->sta_lock, flags);
405 while (!list_empty(&local->sta_pending_list)) {
406 sta = list_first_entry(&local->sta_pending_list,
407 struct sta_info, list);
408 list_del(&sta->list);
409 spin_unlock_irqrestore(&local->sta_lock, flags);
411 sta_info_finish_insert(sta, true, false);
413 spin_lock_irqsave(&local->sta_lock, flags);
415 spin_unlock_irqrestore(&local->sta_lock, flags);
418 static void sta_info_finish_work(struct work_struct *work)
420 struct ieee80211_local *local =
421 container_of(work, struct ieee80211_local, sta_finish_work);
423 mutex_lock(&local->sta_mtx);
424 sta_info_finish_pending(local);
425 mutex_unlock(&local->sta_mtx);
428 static int sta_info_insert_check(struct sta_info *sta)
430 struct ieee80211_sub_if_data *sdata = sta->sdata;
433 * Can't be a WARN_ON because it can be triggered through a race:
434 * something inserts a STA (on one CPU) without holding the RTNL
435 * and another CPU turns off the net device.
437 if (unlikely(!ieee80211_sdata_running(sdata)))
438 return -ENETDOWN;
440 if (WARN_ON(compare_ether_addr(sta->sta.addr, sdata->vif.addr) == 0 ||
441 is_multicast_ether_addr(sta->sta.addr)))
442 return -EINVAL;
444 return 0;
447 static int sta_info_insert_ibss(struct sta_info *sta) __acquires(RCU)
449 struct ieee80211_local *local = sta->local;
450 struct ieee80211_sub_if_data *sdata = sta->sdata;
451 unsigned long flags;
453 spin_lock_irqsave(&local->sta_lock, flags);
454 /* check if STA exists already */
455 if (sta_info_get_bss_rx(sdata, sta->sta.addr)) {
456 spin_unlock_irqrestore(&local->sta_lock, flags);
457 rcu_read_lock();
458 return -EEXIST;
461 local->num_sta++;
462 local->sta_generation++;
463 smp_mb();
464 sta_info_hash_add(local, sta);
466 list_add_tail(&sta->list, &local->sta_pending_list);
468 rcu_read_lock();
469 spin_unlock_irqrestore(&local->sta_lock, flags);
471 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
472 wiphy_debug(local->hw.wiphy, "Added IBSS STA %pM\n",
473 sta->sta.addr);
474 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
476 ieee80211_queue_work(&local->hw, &local->sta_finish_work);
478 return 0;
482 * should be called with sta_mtx locked
483 * this function replaces the mutex lock
484 * with a RCU lock
486 static int sta_info_insert_non_ibss(struct sta_info *sta) __acquires(RCU)
488 struct ieee80211_local *local = sta->local;
489 struct ieee80211_sub_if_data *sdata = sta->sdata;
490 unsigned long flags;
491 struct sta_info *exist_sta;
492 bool dummy_reinsert = false;
493 int err = 0;
495 lockdep_assert_held(&local->sta_mtx);
498 * On first glance, this will look racy, because the code
499 * in this function, which inserts a station with sleeping,
500 * unlocks the sta_lock between checking existence in the
501 * hash table and inserting into it.
503 * However, it is not racy against itself because it keeps
504 * the mutex locked.
507 spin_lock_irqsave(&local->sta_lock, flags);
509 * check if STA exists already.
510 * only accept a scenario of a second call to sta_info_insert_non_ibss
511 * with a dummy station entry that was inserted earlier
512 * in that case - assume that the dummy station flag should
513 * be removed.
515 exist_sta = sta_info_get_bss_rx(sdata, sta->sta.addr);
516 if (exist_sta) {
517 if (exist_sta == sta && sta->dummy) {
518 dummy_reinsert = true;
519 } else {
520 spin_unlock_irqrestore(&local->sta_lock, flags);
521 mutex_unlock(&local->sta_mtx);
522 rcu_read_lock();
523 return -EEXIST;
527 spin_unlock_irqrestore(&local->sta_lock, flags);
529 err = sta_info_finish_insert(sta, false, dummy_reinsert);
530 if (err) {
531 mutex_unlock(&local->sta_mtx);
532 rcu_read_lock();
533 return err;
536 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
537 wiphy_debug(local->hw.wiphy, "Inserted %sSTA %pM\n",
538 sta->dummy ? "dummy " : "", sta->sta.addr);
539 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
541 /* move reference to rcu-protected */
542 rcu_read_lock();
543 mutex_unlock(&local->sta_mtx);
545 if (ieee80211_vif_is_mesh(&sdata->vif))
546 mesh_accept_plinks_update(sdata);
548 return 0;
551 int sta_info_insert_rcu(struct sta_info *sta) __acquires(RCU)
553 struct ieee80211_local *local = sta->local;
554 struct ieee80211_sub_if_data *sdata = sta->sdata;
555 int err = 0;
557 err = sta_info_insert_check(sta);
558 if (err) {
559 rcu_read_lock();
560 goto out_free;
564 * In ad-hoc mode, we sometimes need to insert stations
565 * from tasklet context from the RX path. To avoid races,
566 * always do so in that case -- see the comment below.
568 if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {
569 err = sta_info_insert_ibss(sta);
570 if (err)
571 goto out_free;
573 return 0;
577 * It might seem that the function called below is in race against
578 * the function call above that atomically inserts the station... That,
579 * however, is not true because the above code can only
580 * be invoked for IBSS interfaces, and the below code will
581 * not be -- and the two do not race against each other as
582 * the hash table also keys off the interface.
585 might_sleep();
587 mutex_lock(&local->sta_mtx);
589 err = sta_info_insert_non_ibss(sta);
590 if (err)
591 goto out_free;
593 return 0;
594 out_free:
595 BUG_ON(!err);
596 __sta_info_free(local, sta);
597 return err;
600 int sta_info_insert(struct sta_info *sta)
602 int err = sta_info_insert_rcu(sta);
604 rcu_read_unlock();
606 return err;
609 /* Caller must hold sta->local->sta_mtx */
610 int sta_info_reinsert(struct sta_info *sta)
612 struct ieee80211_local *local = sta->local;
613 int err = 0;
615 err = sta_info_insert_check(sta);
616 if (err) {
617 mutex_unlock(&local->sta_mtx);
618 return err;
621 might_sleep();
623 err = sta_info_insert_non_ibss(sta);
624 rcu_read_unlock();
625 return err;
628 static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid)
631 * This format has been mandated by the IEEE specifications,
632 * so this line may not be changed to use the __set_bit() format.
634 bss->tim[aid / 8] |= (1 << (aid % 8));
637 static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid)
640 * This format has been mandated by the IEEE specifications,
641 * so this line may not be changed to use the __clear_bit() format.
643 bss->tim[aid / 8] &= ~(1 << (aid % 8));
646 static unsigned long ieee80211_tids_for_ac(int ac)
648 /* If we ever support TIDs > 7, this obviously needs to be adjusted */
649 switch (ac) {
650 case IEEE80211_AC_VO:
651 return BIT(6) | BIT(7);
652 case IEEE80211_AC_VI:
653 return BIT(4) | BIT(5);
654 case IEEE80211_AC_BE:
655 return BIT(0) | BIT(3);
656 case IEEE80211_AC_BK:
657 return BIT(1) | BIT(2);
658 default:
659 WARN_ON(1);
660 return 0;
664 void sta_info_recalc_tim(struct sta_info *sta)
666 struct ieee80211_local *local = sta->local;
667 struct ieee80211_if_ap *bss = sta->sdata->bss;
668 unsigned long flags;
669 bool indicate_tim = false;
670 u8 ignore_for_tim = sta->sta.uapsd_queues;
671 int ac;
673 if (WARN_ON_ONCE(!sta->sdata->bss))
674 return;
676 /* No need to do anything if the driver does all */
677 if (local->hw.flags & IEEE80211_HW_AP_LINK_PS)
678 return;
680 if (sta->dead)
681 goto done;
684 * If all ACs are delivery-enabled then we should build
685 * the TIM bit for all ACs anyway; if only some are then
686 * we ignore those and build the TIM bit using only the
687 * non-enabled ones.
689 if (ignore_for_tim == BIT(IEEE80211_NUM_ACS) - 1)
690 ignore_for_tim = 0;
692 for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
693 unsigned long tids;
695 if (ignore_for_tim & BIT(ac))
696 continue;
698 indicate_tim |= !skb_queue_empty(&sta->tx_filtered[ac]) ||
699 !skb_queue_empty(&sta->ps_tx_buf[ac]);
700 if (indicate_tim)
701 break;
703 tids = ieee80211_tids_for_ac(ac);
705 indicate_tim |=
706 sta->driver_buffered_tids & tids;
709 done:
710 spin_lock_irqsave(&local->sta_lock, flags);
712 if (indicate_tim)
713 __bss_tim_set(bss, sta->sta.aid);
714 else
715 __bss_tim_clear(bss, sta->sta.aid);
717 if (local->ops->set_tim) {
718 local->tim_in_locked_section = true;
719 drv_set_tim(local, &sta->sta, indicate_tim);
720 local->tim_in_locked_section = false;
723 spin_unlock_irqrestore(&local->sta_lock, flags);
726 static bool sta_info_buffer_expired(struct sta_info *sta, struct sk_buff *skb)
728 struct ieee80211_tx_info *info;
729 int timeout;
731 if (!skb)
732 return false;
734 info = IEEE80211_SKB_CB(skb);
736 /* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */
737 timeout = (sta->listen_interval *
738 sta->sdata->vif.bss_conf.beacon_int *
739 32 / 15625) * HZ;
740 if (timeout < STA_TX_BUFFER_EXPIRE)
741 timeout = STA_TX_BUFFER_EXPIRE;
742 return time_after(jiffies, info->control.jiffies + timeout);
746 static bool sta_info_cleanup_expire_buffered_ac(struct ieee80211_local *local,
747 struct sta_info *sta, int ac)
749 unsigned long flags;
750 struct sk_buff *skb;
753 * First check for frames that should expire on the filtered
754 * queue. Frames here were rejected by the driver and are on
755 * a separate queue to avoid reordering with normal PS-buffered
756 * frames. They also aren't accounted for right now in the
757 * total_ps_buffered counter.
759 for (;;) {
760 spin_lock_irqsave(&sta->tx_filtered[ac].lock, flags);
761 skb = skb_peek(&sta->tx_filtered[ac]);
762 if (sta_info_buffer_expired(sta, skb))
763 skb = __skb_dequeue(&sta->tx_filtered[ac]);
764 else
765 skb = NULL;
766 spin_unlock_irqrestore(&sta->tx_filtered[ac].lock, flags);
769 * Frames are queued in order, so if this one
770 * hasn't expired yet we can stop testing. If
771 * we actually reached the end of the queue we
772 * also need to stop, of course.
774 if (!skb)
775 break;
776 dev_kfree_skb(skb);
780 * Now also check the normal PS-buffered queue, this will
781 * only find something if the filtered queue was emptied
782 * since the filtered frames are all before the normal PS
783 * buffered frames.
785 for (;;) {
786 spin_lock_irqsave(&sta->ps_tx_buf[ac].lock, flags);
787 skb = skb_peek(&sta->ps_tx_buf[ac]);
788 if (sta_info_buffer_expired(sta, skb))
789 skb = __skb_dequeue(&sta->ps_tx_buf[ac]);
790 else
791 skb = NULL;
792 spin_unlock_irqrestore(&sta->ps_tx_buf[ac].lock, flags);
795 * frames are queued in order, so if this one
796 * hasn't expired yet (or we reached the end of
797 * the queue) we can stop testing
799 if (!skb)
800 break;
802 local->total_ps_buffered--;
803 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
804 printk(KERN_DEBUG "Buffered frame expired (STA %pM)\n",
805 sta->sta.addr);
806 #endif
807 dev_kfree_skb(skb);
811 * Finally, recalculate the TIM bit for this station -- it might
812 * now be clear because the station was too slow to retrieve its
813 * frames.
815 sta_info_recalc_tim(sta);
818 * Return whether there are any frames still buffered, this is
819 * used to check whether the cleanup timer still needs to run,
820 * if there are no frames we don't need to rearm the timer.
822 return !(skb_queue_empty(&sta->ps_tx_buf[ac]) &&
823 skb_queue_empty(&sta->tx_filtered[ac]));
826 static bool sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
827 struct sta_info *sta)
829 bool have_buffered = false;
830 int ac;
832 /* This is only necessary for stations on BSS interfaces */
833 if (!sta->sdata->bss)
834 return false;
836 for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
837 have_buffered |=
838 sta_info_cleanup_expire_buffered_ac(local, sta, ac);
840 return have_buffered;
843 static int __must_check __sta_info_destroy(struct sta_info *sta)
845 struct ieee80211_local *local;
846 struct ieee80211_sub_if_data *sdata;
847 unsigned long flags;
848 int ret, i, ac;
850 might_sleep();
852 if (!sta)
853 return -ENOENT;
855 local = sta->local;
856 sdata = sta->sdata;
859 * Before removing the station from the driver and
860 * rate control, it might still start new aggregation
861 * sessions -- block that to make sure the tear-down
862 * will be sufficient.
864 set_sta_flags(sta, WLAN_STA_BLOCK_BA);
865 ieee80211_sta_tear_down_BA_sessions(sta, true);
867 spin_lock_irqsave(&local->sta_lock, flags);
868 ret = sta_info_hash_del(local, sta);
869 /* this might still be the pending list ... which is fine */
870 if (!ret)
871 list_del(&sta->list);
872 spin_unlock_irqrestore(&local->sta_lock, flags);
873 if (ret)
874 return ret;
876 mutex_lock(&local->key_mtx);
877 for (i = 0; i < NUM_DEFAULT_KEYS; i++)
878 __ieee80211_key_free(key_mtx_dereference(local, sta->gtk[i]));
879 if (sta->ptk)
880 __ieee80211_key_free(key_mtx_dereference(local, sta->ptk));
881 mutex_unlock(&local->key_mtx);
883 sta->dead = true;
885 if (test_and_clear_sta_flags(sta,
886 WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) {
887 BUG_ON(!sdata->bss);
889 atomic_dec(&sdata->bss->num_sta_ps);
890 sta_info_recalc_tim(sta);
893 local->num_sta--;
894 local->sta_generation++;
896 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
897 rcu_assign_pointer(sdata->u.vlan.sta, NULL);
899 if (sta->uploaded) {
900 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
901 sdata = container_of(sdata->bss,
902 struct ieee80211_sub_if_data,
903 u.ap);
904 drv_sta_remove(local, sdata, &sta->sta);
905 sdata = sta->sdata;
909 * At this point, after we wait for an RCU grace period,
910 * neither mac80211 nor the driver can reference this
911 * sta struct any more except by still existing timers
912 * associated with this station that we clean up below.
914 synchronize_rcu();
916 for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
917 local->total_ps_buffered -= skb_queue_len(&sta->ps_tx_buf[ac]);
918 __skb_queue_purge(&sta->ps_tx_buf[ac]);
919 __skb_queue_purge(&sta->tx_filtered[ac]);
922 #ifdef CONFIG_MAC80211_MESH
923 if (ieee80211_vif_is_mesh(&sdata->vif))
924 mesh_accept_plinks_update(sdata);
925 #endif
927 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
928 wiphy_debug(local->hw.wiphy, "Removed STA %pM\n", sta->sta.addr);
929 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
930 cancel_work_sync(&sta->drv_unblock_wk);
932 cfg80211_del_sta(sdata->dev, sta->sta.addr, GFP_KERNEL);
934 rate_control_remove_sta_debugfs(sta);
935 ieee80211_sta_debugfs_remove(sta);
937 #ifdef CONFIG_MAC80211_MESH
938 if (ieee80211_vif_is_mesh(&sta->sdata->vif)) {
939 mesh_plink_deactivate(sta);
940 del_timer_sync(&sta->plink_timer);
942 #endif
944 __sta_info_free(local, sta);
946 return 0;
949 int sta_info_destroy_addr(struct ieee80211_sub_if_data *sdata, const u8 *addr)
951 struct sta_info *sta;
952 int ret;
954 mutex_lock(&sdata->local->sta_mtx);
955 sta = sta_info_get_rx(sdata, addr);
956 ret = __sta_info_destroy(sta);
957 mutex_unlock(&sdata->local->sta_mtx);
959 return ret;
962 int sta_info_destroy_addr_bss(struct ieee80211_sub_if_data *sdata,
963 const u8 *addr)
965 struct sta_info *sta;
966 int ret;
968 mutex_lock(&sdata->local->sta_mtx);
969 sta = sta_info_get_bss_rx(sdata, addr);
970 ret = __sta_info_destroy(sta);
971 mutex_unlock(&sdata->local->sta_mtx);
973 return ret;
976 static void sta_info_cleanup(unsigned long data)
978 struct ieee80211_local *local = (struct ieee80211_local *) data;
979 struct sta_info *sta;
980 bool timer_needed = false;
982 rcu_read_lock();
983 list_for_each_entry_rcu(sta, &local->sta_list, list)
984 if (sta_info_cleanup_expire_buffered(local, sta))
985 timer_needed = true;
986 rcu_read_unlock();
988 if (local->quiescing)
989 return;
991 if (!timer_needed)
992 return;
994 mod_timer(&local->sta_cleanup,
995 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL));
998 void sta_info_init(struct ieee80211_local *local)
1000 spin_lock_init(&local->sta_lock);
1001 mutex_init(&local->sta_mtx);
1002 INIT_LIST_HEAD(&local->sta_list);
1003 INIT_LIST_HEAD(&local->sta_pending_list);
1004 INIT_WORK(&local->sta_finish_work, sta_info_finish_work);
1006 setup_timer(&local->sta_cleanup, sta_info_cleanup,
1007 (unsigned long)local);
1010 void sta_info_stop(struct ieee80211_local *local)
1012 del_timer(&local->sta_cleanup);
1013 sta_info_flush(local, NULL);
1017 * sta_info_flush - flush matching STA entries from the STA table
1019 * Returns the number of removed STA entries.
1021 * @local: local interface data
1022 * @sdata: matching rule for the net device (sta->dev) or %NULL to match all STAs
1024 int sta_info_flush(struct ieee80211_local *local,
1025 struct ieee80211_sub_if_data *sdata)
1027 struct sta_info *sta, *tmp;
1028 int ret = 0;
1030 might_sleep();
1032 mutex_lock(&local->sta_mtx);
1034 sta_info_finish_pending(local);
1036 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
1037 if (!sdata || sdata == sta->sdata)
1038 WARN_ON(__sta_info_destroy(sta));
1040 mutex_unlock(&local->sta_mtx);
1042 return ret;
1045 void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata,
1046 unsigned long exp_time)
1048 struct ieee80211_local *local = sdata->local;
1049 struct sta_info *sta, *tmp;
1051 mutex_lock(&local->sta_mtx);
1052 list_for_each_entry_safe(sta, tmp, &local->sta_list, list)
1053 if (time_after(jiffies, sta->last_rx + exp_time)) {
1054 #ifdef CONFIG_MAC80211_IBSS_DEBUG
1055 printk(KERN_DEBUG "%s: expiring inactive STA %pM\n",
1056 sdata->name, sta->sta.addr);
1057 #endif
1058 WARN_ON(__sta_info_destroy(sta));
1060 mutex_unlock(&local->sta_mtx);
1063 struct ieee80211_sta *ieee80211_find_sta_by_ifaddr(struct ieee80211_hw *hw,
1064 const u8 *addr,
1065 const u8 *localaddr)
1067 struct sta_info *sta, *nxt;
1070 * Just return a random station if localaddr is NULL
1071 * ... first in list.
1073 for_each_sta_info(hw_to_local(hw), addr, sta, nxt) {
1074 if (localaddr &&
1075 compare_ether_addr(sta->sdata->vif.addr, localaddr) != 0)
1076 continue;
1077 if (!sta->uploaded)
1078 return NULL;
1079 return &sta->sta;
1082 return NULL;
1084 EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_ifaddr);
1086 struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_vif *vif,
1087 const u8 *addr)
1089 struct sta_info *sta;
1091 if (!vif)
1092 return NULL;
1094 sta = sta_info_get_bss(vif_to_sdata(vif), addr);
1095 if (!sta)
1096 return NULL;
1098 if (!sta->uploaded)
1099 return NULL;
1101 return &sta->sta;
1103 EXPORT_SYMBOL(ieee80211_find_sta);
1105 static void clear_sta_ps_flags(void *_sta)
1107 struct sta_info *sta = _sta;
1109 clear_sta_flags(sta, WLAN_STA_PS_DRIVER | WLAN_STA_PS_STA);
1112 /* powersave support code */
1113 void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta)
1115 struct ieee80211_sub_if_data *sdata = sta->sdata;
1116 struct ieee80211_local *local = sdata->local;
1117 struct sk_buff_head pending;
1118 int filtered = 0, buffered = 0, ac;
1120 BUILD_BUG_ON(BITS_TO_LONGS(STA_TID_NUM) > 1);
1121 sta->driver_buffered_tids = 0;
1123 if (!(local->hw.flags & IEEE80211_HW_AP_LINK_PS))
1124 drv_sta_notify(local, sdata, STA_NOTIFY_AWAKE, &sta->sta);
1126 skb_queue_head_init(&pending);
1128 /* Send all buffered frames to the station */
1129 for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
1130 int count = skb_queue_len(&pending), tmp;
1132 skb_queue_splice_tail_init(&sta->tx_filtered[ac], &pending);
1133 tmp = skb_queue_len(&pending);
1134 filtered += tmp - count;
1135 count = tmp;
1137 skb_queue_splice_tail_init(&sta->ps_tx_buf[ac], &pending);
1138 tmp = skb_queue_len(&pending);
1139 buffered += tmp - count;
1142 ieee80211_add_pending_skbs_fn(local, &pending, clear_sta_ps_flags, sta);
1144 local->total_ps_buffered -= buffered;
1146 sta_info_recalc_tim(sta);
1148 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1149 printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames "
1150 "since STA not sleeping anymore\n", sdata->name,
1151 sta->sta.addr, sta->sta.aid, filtered, buffered);
1152 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1155 void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta)
1157 struct ieee80211_sub_if_data *sdata = sta->sdata;
1158 struct ieee80211_local *local = sdata->local;
1159 struct sk_buff *skb = NULL;
1160 bool more_data = false;
1161 int ac;
1162 u8 ignore_for_response = sta->sta.uapsd_queues;
1165 * If all ACs are delivery-enabled then we should reply
1166 * from any of them, if only some are enabled we reply
1167 * only from the non-enabled ones.
1169 if (ignore_for_response == BIT(IEEE80211_NUM_ACS) - 1)
1170 ignore_for_response = 0;
1173 * Get response frame and more data bit for it.
1175 for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
1176 if (ignore_for_response & BIT(ac))
1177 continue;
1179 if (!skb) {
1180 skb = skb_dequeue(&sta->tx_filtered[ac]);
1181 if (!skb) {
1182 skb = skb_dequeue(&sta->ps_tx_buf[ac]);
1183 if (skb)
1184 local->total_ps_buffered--;
1188 /* FIXME: take into account driver-buffered frames */
1190 if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
1191 !skb_queue_empty(&sta->ps_tx_buf[ac])) {
1192 more_data = true;
1193 break;
1197 if (skb) {
1198 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1199 struct ieee80211_hdr *hdr =
1200 (struct ieee80211_hdr *) skb->data;
1203 * Tell TX path to send this frame even though the STA may
1204 * still remain is PS mode after this frame exchange.
1206 info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE;
1208 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1209 printk(KERN_DEBUG "STA %pM aid %d: PS Poll\n",
1210 sta->sta.addr, sta->sta.aid);
1211 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1213 /* Use MoreData flag to indicate whether there are more
1214 * buffered frames for this STA */
1215 if (!more_data)
1216 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
1217 else
1218 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
1220 ieee80211_add_pending_skb(local, skb);
1222 sta_info_recalc_tim(sta);
1223 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
1224 } else {
1226 * FIXME: This can be the result of a race condition between
1227 * us expiring a frame and the station polling for it.
1228 * Should we send it a null-func frame indicating we
1229 * have nothing buffered for it?
1231 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
1232 "though there are no buffered frames for it\n",
1233 sdata->name, sta->sta.addr);
1234 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
1238 void ieee80211_sta_block_awake(struct ieee80211_hw *hw,
1239 struct ieee80211_sta *pubsta, bool block)
1241 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1243 trace_api_sta_block_awake(sta->local, pubsta, block);
1245 if (block)
1246 set_sta_flags(sta, WLAN_STA_PS_DRIVER);
1247 else if (test_sta_flags(sta, WLAN_STA_PS_DRIVER))
1248 ieee80211_queue_work(hw, &sta->drv_unblock_wk);
1250 EXPORT_SYMBOL(ieee80211_sta_block_awake);
1252 void ieee80211_sta_set_buffered(struct ieee80211_sta *pubsta,
1253 u8 tid, bool buffered)
1255 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
1257 if (WARN_ON(tid >= STA_TID_NUM))
1258 return;
1260 if (buffered)
1261 set_bit(tid, &sta->driver_buffered_tids);
1262 else
1263 clear_bit(tid, &sta->driver_buffered_tids);
1265 sta_info_recalc_tim(sta);
1267 EXPORT_SYMBOL(ieee80211_sta_set_buffered);