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.
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"
25 #include "debugfs_sta.h"
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 owns
36 * that structure. It must then either destroy it using sta_info_destroy()
37 * (which is pretty useless) or insert it into the hash table using
38 * sta_info_insert() which demotes the reference from ownership to a regular
39 * RCU-protected reference; if the function is called without protection by an
40 * RCU critical section the reference is instantly invalidated. Note that the
41 * caller may not do much with the STA info before inserting it, in particular,
42 * it may not start any mesh peer link management or add 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 * sta 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 assocation response from the AP. For IBSS this occurs when
51 * we receive a probe response or a beacon from target IBSS network. For
52 * WDS we add the sta for the peer imediately upon device open. When using
53 * AP mode we add stations for each respective station upon request from
54 * userspace through nl80211.
56 * Because there are debugfs entries for each station, and adding those
57 * must be able to sleep, it is also possible to "pin" a station entry,
58 * that means it can be removed from the hash table but not be freed.
59 * See the comment in __sta_info_unlink() for more information, this is
60 * an internal capability only.
62 * In order to remove a STA info structure, the caller needs to first
63 * unlink it (sta_info_unlink()) from the list and hash tables and
64 * then destroy it; sta_info_destroy() will wait for an RCU grace period
65 * to elapse before actually freeing it. Due to the pinning and the
66 * possibility of multiple callers trying to remove the same STA info at
67 * the same time, sta_info_unlink() can clear the STA info pointer it is
68 * passed to indicate that the STA info is owned by somebody else now.
70 * If sta_info_unlink() did not clear the pointer then the caller owns
71 * the STA info structure now and is responsible of destroying it with
72 * a call to sta_info_destroy().
74 * In all other cases, there is no concept of ownership on a STA entry,
75 * each structure is owned by the global hash table/list until it is
76 * removed. All users of the structure need to be RCU protected so that
77 * the structure won't be freed before they are done using it.
80 /* Caller must hold local->sta_lock */
81 static int sta_info_hash_del(struct ieee80211_local *local,
86 s = local->sta_hash[STA_HASH(sta->sta.addr)];
90 rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)],
95 while (s->hnext && s->hnext != sta)
98 rcu_assign_pointer(s->hnext, sta->hnext);
105 /* protected by RCU */
106 struct sta_info *sta_info_get(struct ieee80211_local *local, const u8 *addr)
108 struct sta_info *sta;
110 sta = rcu_dereference(local->sta_hash[STA_HASH(addr)]);
112 if (memcmp(sta->sta.addr, addr, ETH_ALEN) == 0)
114 sta = rcu_dereference(sta->hnext);
119 struct sta_info *sta_info_get_by_idx(struct ieee80211_local *local, int idx,
120 struct net_device *dev)
122 struct sta_info *sta;
125 list_for_each_entry_rcu(sta, &local->sta_list, list) {
126 if (dev && dev != sta->sdata->dev)
139 * __sta_info_free - internal STA free helper
141 * @local: pointer to the global information
142 * @sta: STA info to free
144 * This function must undo everything done by sta_info_alloc()
145 * that may happen before sta_info_insert().
147 static void __sta_info_free(struct ieee80211_local *local,
148 struct sta_info *sta)
150 rate_control_free_sta(sta);
151 rate_control_put(sta->rate_ctrl);
153 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
154 printk(KERN_DEBUG "%s: Destroyed STA %pM\n",
155 wiphy_name(local->hw.wiphy), sta->sta.addr);
156 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
161 void sta_info_destroy(struct sta_info *sta)
163 struct ieee80211_local *local;
174 cancel_work_sync(&sta->drv_unblock_wk);
176 rate_control_remove_sta_debugfs(sta);
177 ieee80211_sta_debugfs_remove(sta);
179 #ifdef CONFIG_MAC80211_MESH
180 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
181 mesh_plink_deactivate(sta);
185 * We have only unlinked the key, and actually destroying it
186 * may mean it is removed from hardware which requires that
187 * the key->sta pointer is still valid, so flush the key todo
190 * ieee80211_key_todo() will synchronize_rcu() so after this
191 * nothing can reference this sta struct any more.
193 ieee80211_key_todo();
195 #ifdef CONFIG_MAC80211_MESH
196 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
197 del_timer_sync(&sta->plink_timer);
200 while ((skb = skb_dequeue(&sta->ps_tx_buf)) != NULL) {
201 local->total_ps_buffered--;
202 dev_kfree_skb_any(skb);
205 while ((skb = skb_dequeue(&sta->tx_filtered)) != NULL)
206 dev_kfree_skb_any(skb);
208 for (i = 0; i < STA_TID_NUM; i++) {
209 struct tid_ampdu_rx *tid_rx;
210 struct tid_ampdu_tx *tid_tx;
212 spin_lock_bh(&sta->lock);
213 tid_rx = sta->ampdu_mlme.tid_rx[i];
214 /* Make sure timer won't free the tid_rx struct, see below */
216 tid_rx->shutdown = true;
218 spin_unlock_bh(&sta->lock);
221 * Outside spinlock - shutdown is true now so that the timer
222 * won't free tid_rx, we have to do that now. Can't let the
223 * timer do it because we have to sync the timer outside the
224 * lock that it takes itself.
227 del_timer_sync(&tid_rx->session_timer);
232 * No need to do such complications for TX agg sessions, the
233 * path leading to freeing the tid_tx struct goes via a call
234 * from the driver, and thus needs to look up the sta struct
235 * again, which cannot be found when we get here. Hence, we
236 * just need to delete the timer and free the aggregation
237 * info; we won't be telling the peer about it then but that
238 * doesn't matter if we're not talking to it again anyway.
240 tid_tx = sta->ampdu_mlme.tid_tx[i];
242 del_timer_sync(&tid_tx->addba_resp_timer);
244 * STA removed while aggregation session being
245 * started? Bit odd, but purge frames anyway.
247 skb_queue_purge(&tid_tx->pending);
252 __sta_info_free(local, sta);
256 /* Caller must hold local->sta_lock */
257 static void sta_info_hash_add(struct ieee80211_local *local,
258 struct sta_info *sta)
260 sta->hnext = local->sta_hash[STA_HASH(sta->sta.addr)];
261 rcu_assign_pointer(local->sta_hash[STA_HASH(sta->sta.addr)], sta);
264 static void sta_unblock(struct work_struct *wk)
266 struct sta_info *sta;
268 sta = container_of(wk, struct sta_info, drv_unblock_wk);
273 if (!test_sta_flags(sta, WLAN_STA_PS_STA))
274 ieee80211_sta_ps_deliver_wakeup(sta);
275 else if (test_and_clear_sta_flags(sta, WLAN_STA_PSPOLL))
276 ieee80211_sta_ps_deliver_poll_response(sta);
279 struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
282 struct ieee80211_local *local = sdata->local;
283 struct sta_info *sta;
286 sta = kzalloc(sizeof(*sta) + local->hw.sta_data_size, gfp);
290 spin_lock_init(&sta->lock);
291 spin_lock_init(&sta->flaglock);
292 INIT_WORK(&sta->drv_unblock_wk, sta_unblock);
294 memcpy(sta->sta.addr, addr, ETH_ALEN);
298 sta->rate_ctrl = rate_control_get(local->rate_ctrl);
299 sta->rate_ctrl_priv = rate_control_alloc_sta(sta->rate_ctrl,
301 if (!sta->rate_ctrl_priv) {
302 rate_control_put(sta->rate_ctrl);
307 for (i = 0; i < STA_TID_NUM; i++) {
308 /* timer_to_tid must be initialized with identity mapping to
309 * enable session_timer's data differentiation. refer to
310 * sta_rx_agg_session_timer_expired for useage */
311 sta->timer_to_tid[i] = i;
313 sta->ampdu_mlme.tid_state_rx[i] = HT_AGG_STATE_IDLE;
314 sta->ampdu_mlme.tid_rx[i] = NULL;
316 sta->ampdu_mlme.tid_state_tx[i] = HT_AGG_STATE_IDLE;
317 sta->ampdu_mlme.tid_tx[i] = NULL;
318 sta->ampdu_mlme.addba_req_num[i] = 0;
320 skb_queue_head_init(&sta->ps_tx_buf);
321 skb_queue_head_init(&sta->tx_filtered);
323 for (i = 0; i < NUM_RX_DATA_QUEUES; i++)
324 sta->last_seq_ctrl[i] = cpu_to_le16(USHORT_MAX);
326 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
327 printk(KERN_DEBUG "%s: Allocated STA %pM\n",
328 wiphy_name(local->hw.wiphy), sta->sta.addr);
329 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
331 #ifdef CONFIG_MAC80211_MESH
332 sta->plink_state = PLINK_LISTEN;
333 init_timer(&sta->plink_timer);
339 int sta_info_insert(struct sta_info *sta)
341 struct ieee80211_local *local = sta->local;
342 struct ieee80211_sub_if_data *sdata = sta->sdata;
347 * Can't be a WARN_ON because it can be triggered through a race:
348 * something inserts a STA (on one CPU) without holding the RTNL
349 * and another CPU turns off the net device.
351 if (unlikely(!netif_running(sdata->dev))) {
356 if (WARN_ON(compare_ether_addr(sta->sta.addr, sdata->dev->dev_addr) == 0 ||
357 is_multicast_ether_addr(sta->sta.addr))) {
362 spin_lock_irqsave(&local->sta_lock, flags);
363 /* check if STA exists already */
364 if (sta_info_get(local, sta->sta.addr)) {
365 spin_unlock_irqrestore(&local->sta_lock, flags);
369 list_add(&sta->list, &local->sta_list);
370 local->sta_generation++;
372 sta_info_hash_add(local, sta);
375 if (local->ops->sta_notify) {
376 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
377 sdata = container_of(sdata->bss,
378 struct ieee80211_sub_if_data,
381 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_ADD, &sta->sta);
385 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
386 printk(KERN_DEBUG "%s: Inserted STA %pM\n",
387 wiphy_name(local->hw.wiphy), sta->sta.addr);
388 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
390 spin_unlock_irqrestore(&local->sta_lock, flags);
392 #ifdef CONFIG_MAC80211_DEBUGFS
394 * Debugfs entry adding might sleep, so schedule process
395 * context task for adding entry for STAs that do not yet
397 * NOTE: due to auto-freeing semantics this may only be done
398 * if the insertion is successful!
400 schedule_work(&local->sta_debugfs_add);
403 if (ieee80211_vif_is_mesh(&sdata->vif))
404 mesh_accept_plinks_update(sdata);
409 __sta_info_free(local, sta);
413 static inline void __bss_tim_set(struct ieee80211_if_ap *bss, u16 aid)
416 * This format has been mandated by the IEEE specifications,
417 * so this line may not be changed to use the __set_bit() format.
419 bss->tim[aid / 8] |= (1 << (aid % 8));
422 static inline void __bss_tim_clear(struct ieee80211_if_ap *bss, u16 aid)
425 * This format has been mandated by the IEEE specifications,
426 * so this line may not be changed to use the __clear_bit() format.
428 bss->tim[aid / 8] &= ~(1 << (aid % 8));
431 static void __sta_info_set_tim_bit(struct ieee80211_if_ap *bss,
432 struct sta_info *sta)
436 __bss_tim_set(bss, sta->sta.aid);
438 if (sta->local->ops->set_tim) {
439 sta->local->tim_in_locked_section = true;
440 drv_set_tim(sta->local, &sta->sta, true);
441 sta->local->tim_in_locked_section = false;
445 void sta_info_set_tim_bit(struct sta_info *sta)
449 BUG_ON(!sta->sdata->bss);
451 spin_lock_irqsave(&sta->local->sta_lock, flags);
452 __sta_info_set_tim_bit(sta->sdata->bss, sta);
453 spin_unlock_irqrestore(&sta->local->sta_lock, flags);
456 static void __sta_info_clear_tim_bit(struct ieee80211_if_ap *bss,
457 struct sta_info *sta)
461 __bss_tim_clear(bss, sta->sta.aid);
463 if (sta->local->ops->set_tim) {
464 sta->local->tim_in_locked_section = true;
465 drv_set_tim(sta->local, &sta->sta, false);
466 sta->local->tim_in_locked_section = false;
470 void sta_info_clear_tim_bit(struct sta_info *sta)
474 BUG_ON(!sta->sdata->bss);
476 spin_lock_irqsave(&sta->local->sta_lock, flags);
477 __sta_info_clear_tim_bit(sta->sdata->bss, sta);
478 spin_unlock_irqrestore(&sta->local->sta_lock, flags);
481 static void __sta_info_unlink(struct sta_info **sta)
483 struct ieee80211_local *local = (*sta)->local;
484 struct ieee80211_sub_if_data *sdata = (*sta)->sdata;
486 * pull caller's reference if we're already gone.
488 if (sta_info_hash_del(local, *sta)) {
494 ieee80211_key_free((*sta)->key);
495 WARN_ON((*sta)->key);
498 list_del(&(*sta)->list);
501 if (test_and_clear_sta_flags(*sta,
502 WLAN_STA_PS_STA | WLAN_STA_PS_DRIVER)) {
505 atomic_dec(&sdata->bss->num_sta_ps);
506 __sta_info_clear_tim_bit(sdata->bss, *sta);
510 local->sta_generation++;
512 if (local->ops->sta_notify) {
513 if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
514 sdata = container_of(sdata->bss,
515 struct ieee80211_sub_if_data,
518 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_REMOVE,
520 sdata = (*sta)->sdata;
523 if (ieee80211_vif_is_mesh(&sdata->vif)) {
524 mesh_accept_plinks_update(sdata);
525 #ifdef CONFIG_MAC80211_MESH
526 del_timer(&(*sta)->plink_timer);
530 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
531 printk(KERN_DEBUG "%s: Removed STA %pM\n",
532 wiphy_name(local->hw.wiphy), (*sta)->sta.addr);
533 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
536 * Finally, pull caller's reference if the STA is pinned by the
537 * task that is adding the debugfs entries. In that case, we
538 * leave the STA "to be freed".
540 * The rules are not trivial, but not too complex either:
541 * (1) pin_status is only modified under the sta_lock
542 * (2) STAs may only be pinned under the RTNL so that
543 * sta_info_flush() is guaranteed to actually destroy
544 * all STAs that are active for a given interface, this
545 * is required for correctness because otherwise we
546 * could notify a driver that an interface is going
547 * away and only after that (!) notify it about a STA
548 * on that interface going away.
549 * (3) sta_info_debugfs_add_work() will set the status
550 * to PINNED when it found an item that needs a new
551 * debugfs directory created. In that case, that item
552 * must not be freed although all *RCU* users are done
553 * with it. Hence, we tell the caller of _unlink()
554 * that the item is already gone (as can happen when
555 * two tasks try to unlink/destroy at the same time)
556 * (4) We set the pin_status to DESTROY here when we
558 * (5) sta_info_debugfs_add_work() will reset the pin_status
559 * from PINNED to NORMAL when it is done with the item,
560 * but will check for DESTROY before resetting it in
561 * which case it will free the item.
563 if ((*sta)->pin_status == STA_INFO_PIN_STAT_PINNED) {
564 (*sta)->pin_status = STA_INFO_PIN_STAT_DESTROY;
570 void sta_info_unlink(struct sta_info **sta)
572 struct ieee80211_local *local = (*sta)->local;
575 spin_lock_irqsave(&local->sta_lock, flags);
576 __sta_info_unlink(sta);
577 spin_unlock_irqrestore(&local->sta_lock, flags);
580 static int sta_info_buffer_expired(struct sta_info *sta,
583 struct ieee80211_tx_info *info;
589 info = IEEE80211_SKB_CB(skb);
591 /* Timeout: (2 * listen_interval * beacon_int * 1024 / 1000000) sec */
592 timeout = (sta->listen_interval *
593 sta->sdata->vif.bss_conf.beacon_int *
595 if (timeout < STA_TX_BUFFER_EXPIRE)
596 timeout = STA_TX_BUFFER_EXPIRE;
597 return time_after(jiffies, info->control.jiffies + timeout);
601 static void sta_info_cleanup_expire_buffered(struct ieee80211_local *local,
602 struct sta_info *sta)
606 struct ieee80211_sub_if_data *sdata;
608 if (skb_queue_empty(&sta->ps_tx_buf))
612 spin_lock_irqsave(&sta->ps_tx_buf.lock, flags);
613 skb = skb_peek(&sta->ps_tx_buf);
614 if (sta_info_buffer_expired(sta, skb))
615 skb = __skb_dequeue(&sta->ps_tx_buf);
618 spin_unlock_irqrestore(&sta->ps_tx_buf.lock, flags);
624 local->total_ps_buffered--;
625 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
626 printk(KERN_DEBUG "Buffered frame expired (STA %pM)\n",
631 if (skb_queue_empty(&sta->ps_tx_buf))
632 sta_info_clear_tim_bit(sta);
637 static void sta_info_cleanup(unsigned long data)
639 struct ieee80211_local *local = (struct ieee80211_local *) data;
640 struct sta_info *sta;
643 list_for_each_entry_rcu(sta, &local->sta_list, list)
644 sta_info_cleanup_expire_buffered(local, sta);
647 if (local->quiescing)
650 local->sta_cleanup.expires =
651 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL);
652 add_timer(&local->sta_cleanup);
655 #ifdef CONFIG_MAC80211_DEBUGFS
657 * See comment in __sta_info_unlink,
658 * caller must hold local->sta_lock.
660 static void __sta_info_pin(struct sta_info *sta)
662 WARN_ON(sta->pin_status != STA_INFO_PIN_STAT_NORMAL);
663 sta->pin_status = STA_INFO_PIN_STAT_PINNED;
667 * See comment in __sta_info_unlink, returns sta if it
668 * needs to be destroyed.
670 static struct sta_info *__sta_info_unpin(struct sta_info *sta)
672 struct sta_info *ret = NULL;
675 spin_lock_irqsave(&sta->local->sta_lock, flags);
676 WARN_ON(sta->pin_status != STA_INFO_PIN_STAT_DESTROY &&
677 sta->pin_status != STA_INFO_PIN_STAT_PINNED);
678 if (sta->pin_status == STA_INFO_PIN_STAT_DESTROY)
680 sta->pin_status = STA_INFO_PIN_STAT_NORMAL;
681 spin_unlock_irqrestore(&sta->local->sta_lock, flags);
686 static void sta_info_debugfs_add_work(struct work_struct *work)
688 struct ieee80211_local *local =
689 container_of(work, struct ieee80211_local, sta_debugfs_add);
690 struct sta_info *sta, *tmp;
693 /* We need to keep the RTNL across the whole pinned status. */
698 spin_lock_irqsave(&local->sta_lock, flags);
699 list_for_each_entry(tmp, &local->sta_list, list) {
701 * debugfs.add_has_run will be set by
702 * ieee80211_sta_debugfs_add regardless
703 * of what else it does.
705 if (!tmp->debugfs.add_has_run) {
711 spin_unlock_irqrestore(&local->sta_lock, flags);
716 ieee80211_sta_debugfs_add(sta);
717 rate_control_add_sta_debugfs(sta);
719 sta = __sta_info_unpin(sta);
720 sta_info_destroy(sta);
726 void sta_info_init(struct ieee80211_local *local)
728 spin_lock_init(&local->sta_lock);
729 INIT_LIST_HEAD(&local->sta_list);
731 setup_timer(&local->sta_cleanup, sta_info_cleanup,
732 (unsigned long)local);
733 local->sta_cleanup.expires =
734 round_jiffies(jiffies + STA_INFO_CLEANUP_INTERVAL);
736 #ifdef CONFIG_MAC80211_DEBUGFS
737 INIT_WORK(&local->sta_debugfs_add, sta_info_debugfs_add_work);
741 int sta_info_start(struct ieee80211_local *local)
743 add_timer(&local->sta_cleanup);
747 void sta_info_stop(struct ieee80211_local *local)
749 del_timer(&local->sta_cleanup);
750 #ifdef CONFIG_MAC80211_DEBUGFS
752 * Make sure the debugfs adding work isn't pending after this
753 * because we're about to be destroyed. It doesn't matter
754 * whether it ran or not since we're going to flush all STAs
757 cancel_work_sync(&local->sta_debugfs_add);
760 sta_info_flush(local, NULL);
764 * sta_info_flush - flush matching STA entries from the STA table
766 * Returns the number of removed STA entries.
768 * @local: local interface data
769 * @sdata: matching rule for the net device (sta->dev) or %NULL to match all STAs
771 int sta_info_flush(struct ieee80211_local *local,
772 struct ieee80211_sub_if_data *sdata)
774 struct sta_info *sta, *tmp;
781 spin_lock_irqsave(&local->sta_lock, flags);
782 list_for_each_entry_safe(sta, tmp, &local->sta_list, list) {
783 if (!sdata || sdata == sta->sdata) {
784 __sta_info_unlink(&sta);
786 list_add_tail(&sta->list, &tmp_list);
791 spin_unlock_irqrestore(&local->sta_lock, flags);
793 list_for_each_entry_safe(sta, tmp, &tmp_list, list)
794 sta_info_destroy(sta);
799 void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata,
800 unsigned long exp_time)
802 struct ieee80211_local *local = sdata->local;
803 struct sta_info *sta, *tmp;
807 spin_lock_irqsave(&local->sta_lock, flags);
808 list_for_each_entry_safe(sta, tmp, &local->sta_list, list)
809 if (time_after(jiffies, sta->last_rx + exp_time)) {
810 #ifdef CONFIG_MAC80211_IBSS_DEBUG
811 printk(KERN_DEBUG "%s: expiring inactive STA %pM\n",
812 sdata->dev->name, sta->sta.addr);
814 __sta_info_unlink(&sta);
816 list_add(&sta->list, &tmp_list);
818 spin_unlock_irqrestore(&local->sta_lock, flags);
820 list_for_each_entry_safe(sta, tmp, &tmp_list, list)
821 sta_info_destroy(sta);
824 struct ieee80211_sta *ieee80211_find_sta_by_hw(struct ieee80211_hw *hw,
827 struct sta_info *sta = sta_info_get(hw_to_local(hw), addr);
833 EXPORT_SYMBOL_GPL(ieee80211_find_sta_by_hw);
835 struct ieee80211_sta *ieee80211_find_sta(struct ieee80211_vif *vif,
838 struct ieee80211_sub_if_data *sdata;
843 sdata = vif_to_sdata(vif);
845 return ieee80211_find_sta_by_hw(&sdata->local->hw, addr);
847 EXPORT_SYMBOL(ieee80211_find_sta);
849 /* powersave support code */
850 void ieee80211_sta_ps_deliver_wakeup(struct sta_info *sta)
852 struct ieee80211_sub_if_data *sdata = sta->sdata;
853 struct ieee80211_local *local = sdata->local;
856 drv_sta_notify(local, &sdata->vif, STA_NOTIFY_AWAKE, &sta->sta);
858 if (!skb_queue_empty(&sta->ps_tx_buf))
859 sta_info_clear_tim_bit(sta);
861 /* Send all buffered frames to the station */
862 sent = ieee80211_add_pending_skbs(local, &sta->tx_filtered);
863 buffered = ieee80211_add_pending_skbs(local, &sta->ps_tx_buf);
865 local->total_ps_buffered -= buffered;
867 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
868 printk(KERN_DEBUG "%s: STA %pM aid %d sending %d filtered/%d PS frames "
869 "since STA not sleeping anymore\n", sdata->dev->name,
870 sta->sta.addr, sta->sta.aid, sent - buffered, buffered);
871 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
874 void ieee80211_sta_ps_deliver_poll_response(struct sta_info *sta)
876 struct ieee80211_sub_if_data *sdata = sta->sdata;
877 struct ieee80211_local *local = sdata->local;
881 skb = skb_dequeue(&sta->tx_filtered);
883 skb = skb_dequeue(&sta->ps_tx_buf);
885 local->total_ps_buffered--;
887 no_pending_pkts = skb_queue_empty(&sta->tx_filtered) &&
888 skb_queue_empty(&sta->ps_tx_buf);
891 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
892 struct ieee80211_hdr *hdr =
893 (struct ieee80211_hdr *) skb->data;
896 * Tell TX path to send this frame even though the STA may
897 * still remain is PS mode after this frame exchange.
899 info->flags |= IEEE80211_TX_CTL_PSPOLL_RESPONSE;
901 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
902 printk(KERN_DEBUG "STA %pM aid %d: PS Poll (entries after %d)\n",
903 sta->sta.addr, sta->sta.aid,
904 skb_queue_len(&sta->ps_tx_buf));
905 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
907 /* Use MoreData flag to indicate whether there are more
908 * buffered frames for this STA */
910 hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
912 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_MOREDATA);
914 ieee80211_add_pending_skb(local, skb);
917 sta_info_clear_tim_bit(sta);
918 #ifdef CONFIG_MAC80211_VERBOSE_PS_DEBUG
921 * FIXME: This can be the result of a race condition between
922 * us expiring a frame and the station polling for it.
923 * Should we send it a null-func frame indicating we
924 * have nothing buffered for it?
926 printk(KERN_DEBUG "%s: STA %pM sent PS Poll even "
927 "though there are no buffered frames for it\n",
928 sdata->dev->name, sta->sta.addr);
929 #endif /* CONFIG_MAC80211_VERBOSE_PS_DEBUG */
933 void ieee80211_sta_block_awake(struct ieee80211_hw *hw,
934 struct ieee80211_sta *pubsta, bool block)
936 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
939 set_sta_flags(sta, WLAN_STA_PS_DRIVER);
941 ieee80211_queue_work(hw, &sta->drv_unblock_wk);
943 EXPORT_SYMBOL(ieee80211_sta_block_awake);