4 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
5 * Copyright 2002-2005, Instant802 Networks, Inc.
6 * Copyright 2005-2006, Devicescape Software, Inc.
7 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
8 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
9 * Copyright 2007-2010, Intel Corporation
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
16 #include <linux/ieee80211.h>
17 #include <linux/slab.h>
18 #include <linux/export.h>
19 #include <net/mac80211.h>
20 #include "ieee80211_i.h"
21 #include "driver-ops.h"
25 * DOC: TX A-MPDU aggregation
27 * Aggregation on the TX side requires setting the hardware flag
28 * %IEEE80211_HW_AMPDU_AGGREGATION. The driver will then be handed
29 * packets with a flag indicating A-MPDU aggregation. The driver
30 * or device is responsible for actually aggregating the frames,
31 * as well as deciding how many and which to aggregate.
33 * When TX aggregation is started by some subsystem (usually the rate
34 * control algorithm would be appropriate) by calling the
35 * ieee80211_start_tx_ba_session() function, the driver will be
36 * notified via its @ampdu_action function, with the
37 * %IEEE80211_AMPDU_TX_START action.
39 * In response to that, the driver is later required to call the
40 * ieee80211_start_tx_ba_cb_irqsafe() function, which will really
41 * start the aggregation session after the peer has also responded.
42 * If the peer responds negatively, the session will be stopped
43 * again right away. Note that it is possible for the aggregation
44 * session to be stopped before the driver has indicated that it
45 * is done setting it up, in which case it must not indicate the
48 * Also note that, since we also need to wait for a response from
49 * the peer, the driver is notified of the completion of the
50 * handshake by the %IEEE80211_AMPDU_TX_OPERATIONAL action to the
51 * @ampdu_action callback.
53 * Similarly, when the aggregation session is stopped by the peer
54 * or something calling ieee80211_stop_tx_ba_session(), the driver's
55 * @ampdu_action function will be called with the action
56 * %IEEE80211_AMPDU_TX_STOP. In this case, the call must not fail,
57 * and the driver must later call ieee80211_stop_tx_ba_cb_irqsafe().
60 static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
61 const u8 *da, u16 tid,
62 u8 dialog_token, u16 start_seq_num,
63 u16 agg_size, u16 timeout)
65 struct ieee80211_local *local = sdata->local;
67 struct ieee80211_mgmt *mgmt;
70 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
75 skb_reserve(skb, local->hw.extra_tx_headroom);
76 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
78 memcpy(mgmt->da, da, ETH_ALEN);
79 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
80 if (sdata->vif.type == NL80211_IFTYPE_AP ||
81 sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
82 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
83 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
84 else if (sdata->vif.type == NL80211_IFTYPE_STATION)
85 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
87 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
88 IEEE80211_STYPE_ACTION);
90 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
92 mgmt->u.action.category = WLAN_CATEGORY_BACK;
93 mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
95 mgmt->u.action.u.addba_req.dialog_token = dialog_token;
96 capab = (u16)(1 << 1); /* bit 1 aggregation policy */
97 capab |= (u16)(tid << 2); /* bit 5:2 TID number */
98 capab |= (u16)(agg_size << 6); /* bit 15:6 max size of aggergation */
100 mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
102 mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
103 mgmt->u.action.u.addba_req.start_seq_num =
104 cpu_to_le16(start_seq_num << 4);
106 ieee80211_tx_skb(sdata, skb);
109 void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn)
111 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
112 struct ieee80211_local *local = sdata->local;
114 struct ieee80211_bar *bar;
117 skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
121 skb_reserve(skb, local->hw.extra_tx_headroom);
122 bar = (struct ieee80211_bar *)skb_put(skb, sizeof(*bar));
123 memset(bar, 0, sizeof(*bar));
124 bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
125 IEEE80211_STYPE_BACK_REQ);
126 memcpy(bar->ra, ra, ETH_ALEN);
127 memcpy(bar->ta, sdata->vif.addr, ETH_ALEN);
128 bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
129 bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
130 bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT);
131 bar->control = cpu_to_le16(bar_control);
132 bar->start_seq_num = cpu_to_le16(ssn);
134 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
135 ieee80211_tx_skb(sdata, skb);
137 EXPORT_SYMBOL(ieee80211_send_bar);
139 void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
140 struct tid_ampdu_tx *tid_tx)
142 lockdep_assert_held(&sta->ampdu_mlme.mtx);
143 lockdep_assert_held(&sta->lock);
144 rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
147 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
148 enum ieee80211_back_parties initiator,
151 struct ieee80211_local *local = sta->local;
152 struct tid_ampdu_tx *tid_tx;
155 lockdep_assert_held(&sta->ampdu_mlme.mtx);
157 spin_lock_bh(&sta->lock);
159 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
161 spin_unlock_bh(&sta->lock);
165 if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
166 /* not even started yet! */
167 ieee80211_assign_tid_tx(sta, tid, NULL);
168 spin_unlock_bh(&sta->lock);
169 kfree_rcu(tid_tx, rcu_head);
173 spin_unlock_bh(&sta->lock);
175 #ifdef CONFIG_MAC80211_HT_DEBUG
176 printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
178 #endif /* CONFIG_MAC80211_HT_DEBUG */
180 set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
182 del_timer_sync(&tid_tx->addba_resp_timer);
183 del_timer_sync(&tid_tx->session_timer);
186 * After this packets are no longer handed right through
187 * to the driver but are put onto tid_tx->pending instead,
188 * with locking to ensure proper access.
190 clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
192 tid_tx->stop_initiator = initiator;
193 tid_tx->tx_stop = tx;
195 ret = drv_ampdu_action(local, sta->sdata,
196 IEEE80211_AMPDU_TX_STOP,
197 &sta->sta, tid, NULL, 0);
199 /* HW shall not deny going back to legacy */
202 * We may have pending packets get stuck in this case...
203 * Not bothering with a workaround for now.
211 * After sending add Block Ack request we activated a timer until
212 * add Block Ack response will arrive from the recipient.
213 * If this timer expires sta_addba_resp_timer_expired will be executed.
215 static void sta_addba_resp_timer_expired(unsigned long data)
217 /* not an elegant detour, but there is no choice as the timer passes
218 * only one argument, and both sta_info and TID are needed, so init
219 * flow in sta_info_create gives the TID as data, while the timer_to_id
220 * array gives the sta through container_of */
221 u16 tid = *(u8 *)data;
222 struct sta_info *sta = container_of((void *)data,
223 struct sta_info, timer_to_tid[tid]);
224 struct tid_ampdu_tx *tid_tx;
226 /* check if the TID waits for addBA response */
228 tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
230 test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
232 #ifdef CONFIG_MAC80211_HT_DEBUG
233 printk(KERN_DEBUG "timer expired on tid %d but we are not "
234 "(or no longer) expecting addBA response there\n",
240 #ifdef CONFIG_MAC80211_HT_DEBUG
241 printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
244 ieee80211_stop_tx_ba_session(&sta->sta, tid);
248 static inline int ieee80211_ac_from_tid(int tid)
250 return ieee802_1d_to_ac[tid & 7];
254 * When multiple aggregation sessions on multiple stations
255 * are being created/destroyed simultaneously, we need to
256 * refcount the global queue stop caused by that in order
257 * to not get into a situation where one of the aggregation
258 * setup or teardown re-enables queues before the other is
259 * ready to handle that.
261 * These two functions take care of this issue by keeping
262 * a global "agg_queue_stop" refcount.
264 static void __acquires(agg_queue)
265 ieee80211_stop_queue_agg(struct ieee80211_local *local, int tid)
267 int queue = ieee80211_ac_from_tid(tid);
269 if (atomic_inc_return(&local->agg_queue_stop[queue]) == 1)
270 ieee80211_stop_queue_by_reason(
272 IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
273 __acquire(agg_queue);
276 static void __releases(agg_queue)
277 ieee80211_wake_queue_agg(struct ieee80211_local *local, int tid)
279 int queue = ieee80211_ac_from_tid(tid);
281 if (atomic_dec_return(&local->agg_queue_stop[queue]) == 0)
282 ieee80211_wake_queue_by_reason(
284 IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
285 __release(agg_queue);
288 void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
290 struct tid_ampdu_tx *tid_tx;
291 struct ieee80211_local *local = sta->local;
292 struct ieee80211_sub_if_data *sdata = sta->sdata;
296 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
299 * While we're asking the driver about the aggregation,
300 * stop the AC queue so that we don't have to worry
301 * about frames that came in while we were doing that,
302 * which would require us to put them to the AC pending
303 * afterwards which just makes the code more complex.
305 ieee80211_stop_queue_agg(local, tid);
307 clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
310 * make sure no packets are being processed to get
311 * valid starting sequence number
315 start_seq_num = sta->tid_seq[tid] >> 4;
317 ret = drv_ampdu_action(local, sdata, IEEE80211_AMPDU_TX_START,
318 &sta->sta, tid, &start_seq_num, 0);
320 #ifdef CONFIG_MAC80211_HT_DEBUG
321 printk(KERN_DEBUG "BA request denied - HW unavailable for"
324 spin_lock_bh(&sta->lock);
325 ieee80211_assign_tid_tx(sta, tid, NULL);
326 spin_unlock_bh(&sta->lock);
328 ieee80211_wake_queue_agg(local, tid);
329 kfree_rcu(tid_tx, rcu_head);
333 /* we can take packets again now */
334 ieee80211_wake_queue_agg(local, tid);
336 /* activate the timer for the recipient's addBA response */
337 mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
338 #ifdef CONFIG_MAC80211_HT_DEBUG
339 printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
342 spin_lock_bh(&sta->lock);
343 sta->ampdu_mlme.addba_req_num[tid]++;
344 spin_unlock_bh(&sta->lock);
346 /* send AddBA request */
347 ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
348 tid_tx->dialog_token, start_seq_num,
349 local->hw.max_tx_aggregation_subframes,
354 * After accepting the AddBA Response we activated a timer,
355 * resetting it after each frame that we send.
357 static void sta_tx_agg_session_timer_expired(unsigned long data)
359 /* not an elegant detour, but there is no choice as the timer passes
360 * only one argument, and various sta_info are needed here, so init
361 * flow in sta_info_create gives the TID as data, while the timer_to_id
362 * array gives the sta through container_of */
363 u8 *ptid = (u8 *)data;
364 u8 *timer_to_id = ptid - *ptid;
365 struct sta_info *sta = container_of(timer_to_id, struct sta_info,
368 #ifdef CONFIG_MAC80211_HT_DEBUG
369 printk(KERN_DEBUG "tx session timer expired on tid %d\n", (u16)*ptid);
372 ieee80211_stop_tx_ba_session(&sta->sta, *ptid);
375 int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
378 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
379 struct ieee80211_sub_if_data *sdata = sta->sdata;
380 struct ieee80211_local *local = sdata->local;
381 struct tid_ampdu_tx *tid_tx;
384 trace_api_start_tx_ba_session(pubsta, tid);
386 if (WARN_ON(!local->ops->ampdu_action))
389 if ((tid >= STA_TID_NUM) ||
390 !(local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) ||
391 (local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW))
394 #ifdef CONFIG_MAC80211_HT_DEBUG
395 printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
397 #endif /* CONFIG_MAC80211_HT_DEBUG */
399 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
400 sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
401 sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
402 sdata->vif.type != NL80211_IFTYPE_AP)
405 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
406 #ifdef CONFIG_MAC80211_HT_DEBUG
407 printk(KERN_DEBUG "BA sessions blocked. "
408 "Denying BA session request\n");
413 spin_lock_bh(&sta->lock);
415 /* we have tried too many times, receiver does not want A-MPDU */
416 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
421 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
422 /* check if the TID is not in aggregation flow already */
423 if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) {
424 #ifdef CONFIG_MAC80211_HT_DEBUG
425 printk(KERN_DEBUG "BA request denied - session is not "
426 "idle on tid %u\n", tid);
427 #endif /* CONFIG_MAC80211_HT_DEBUG */
432 /* prepare A-MPDU MLME for Tx aggregation */
433 tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
439 skb_queue_head_init(&tid_tx->pending);
440 __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
442 tid_tx->timeout = timeout;
445 tid_tx->addba_resp_timer.function = sta_addba_resp_timer_expired;
446 tid_tx->addba_resp_timer.data = (unsigned long)&sta->timer_to_tid[tid];
447 init_timer(&tid_tx->addba_resp_timer);
450 tid_tx->session_timer.function = sta_tx_agg_session_timer_expired;
451 tid_tx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid];
452 init_timer(&tid_tx->session_timer);
454 /* assign a dialog token */
455 sta->ampdu_mlme.dialog_token_allocator++;
456 tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
459 * Finally, assign it to the start array; the work item will
460 * collect it and move it to the normal array.
462 sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
464 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
466 /* this flow continues off the work */
468 spin_unlock_bh(&sta->lock);
471 EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
474 * splice packets from the STA's pending to the local pending,
475 * requires a call to ieee80211_agg_splice_finish later
477 static void __acquires(agg_queue)
478 ieee80211_agg_splice_packets(struct ieee80211_local *local,
479 struct tid_ampdu_tx *tid_tx, u16 tid)
481 int queue = ieee80211_ac_from_tid(tid);
484 ieee80211_stop_queue_agg(local, tid);
486 if (WARN(!tid_tx, "TID %d gone but expected when splicing aggregates"
487 " from the pending queue\n", tid))
490 if (!skb_queue_empty(&tid_tx->pending)) {
491 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
492 /* copy over remaining packets */
493 skb_queue_splice_tail_init(&tid_tx->pending,
494 &local->pending[queue]);
495 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
499 static void __releases(agg_queue)
500 ieee80211_agg_splice_finish(struct ieee80211_local *local, u16 tid)
502 ieee80211_wake_queue_agg(local, tid);
505 static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
506 struct sta_info *sta, u16 tid)
508 struct tid_ampdu_tx *tid_tx;
510 lockdep_assert_held(&sta->ampdu_mlme.mtx);
512 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
514 #ifdef CONFIG_MAC80211_HT_DEBUG
515 printk(KERN_DEBUG "Aggregation is on for tid %d\n", tid);
518 drv_ampdu_action(local, sta->sdata,
519 IEEE80211_AMPDU_TX_OPERATIONAL,
520 &sta->sta, tid, NULL, tid_tx->buf_size);
523 * synchronize with TX path, while splicing the TX path
524 * should block so it won't put more packets onto pending.
526 spin_lock_bh(&sta->lock);
528 ieee80211_agg_splice_packets(local, tid_tx, tid);
530 * Now mark as operational. This will be visible
531 * in the TX path, and lets it go lock-free in
534 set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
535 ieee80211_agg_splice_finish(local, tid);
537 spin_unlock_bh(&sta->lock);
540 void ieee80211_start_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u16 tid)
542 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
543 struct ieee80211_local *local = sdata->local;
544 struct sta_info *sta;
545 struct tid_ampdu_tx *tid_tx;
547 trace_api_start_tx_ba_cb(sdata, ra, tid);
549 if (tid >= STA_TID_NUM) {
550 #ifdef CONFIG_MAC80211_HT_DEBUG
551 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
557 mutex_lock(&local->sta_mtx);
558 sta = sta_info_get_bss(sdata, ra);
560 mutex_unlock(&local->sta_mtx);
561 #ifdef CONFIG_MAC80211_HT_DEBUG
562 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
567 mutex_lock(&sta->ampdu_mlme.mtx);
568 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
570 if (WARN_ON(!tid_tx)) {
571 #ifdef CONFIG_MAC80211_HT_DEBUG
572 printk(KERN_DEBUG "addBA was not requested!\n");
577 if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
580 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
581 ieee80211_agg_tx_operational(local, sta, tid);
584 mutex_unlock(&sta->ampdu_mlme.mtx);
585 mutex_unlock(&local->sta_mtx);
588 void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
589 const u8 *ra, u16 tid)
591 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
592 struct ieee80211_local *local = sdata->local;
593 struct ieee80211_ra_tid *ra_tid;
594 struct sk_buff *skb = dev_alloc_skb(0);
599 ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
600 memcpy(&ra_tid->ra, ra, ETH_ALEN);
603 skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_START;
604 skb_queue_tail(&sdata->skb_queue, skb);
605 ieee80211_queue_work(&local->hw, &sdata->work);
607 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
609 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
610 enum ieee80211_back_parties initiator,
615 mutex_lock(&sta->ampdu_mlme.mtx);
617 ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator, tx);
619 mutex_unlock(&sta->ampdu_mlme.mtx);
624 int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
626 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
627 struct ieee80211_sub_if_data *sdata = sta->sdata;
628 struct ieee80211_local *local = sdata->local;
629 struct tid_ampdu_tx *tid_tx;
632 trace_api_stop_tx_ba_session(pubsta, tid);
634 if (!local->ops->ampdu_action)
637 if (tid >= STA_TID_NUM)
640 spin_lock_bh(&sta->lock);
641 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
648 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
649 /* already in progress stopping it */
654 set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
655 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
658 spin_unlock_bh(&sta->lock);
661 EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
663 void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
665 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
666 struct ieee80211_local *local = sdata->local;
667 struct sta_info *sta;
668 struct tid_ampdu_tx *tid_tx;
670 trace_api_stop_tx_ba_cb(sdata, ra, tid);
672 if (tid >= STA_TID_NUM) {
673 #ifdef CONFIG_MAC80211_HT_DEBUG
674 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
680 #ifdef CONFIG_MAC80211_HT_DEBUG
681 printk(KERN_DEBUG "Stopping Tx BA session for %pM tid %d\n",
683 #endif /* CONFIG_MAC80211_HT_DEBUG */
685 mutex_lock(&local->sta_mtx);
687 sta = sta_info_get_bss(sdata, ra);
689 #ifdef CONFIG_MAC80211_HT_DEBUG
690 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
695 mutex_lock(&sta->ampdu_mlme.mtx);
696 spin_lock_bh(&sta->lock);
697 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
699 if (!tid_tx || !test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
700 #ifdef CONFIG_MAC80211_HT_DEBUG
701 printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
706 if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
707 ieee80211_send_delba(sta->sdata, ra, tid,
708 WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
711 * When we get here, the TX path will not be lockless any more wrt.
712 * aggregation, since the OPERATIONAL bit has long been cleared.
713 * Thus it will block on getting the lock, if it occurs. So if we
714 * stop the queue now, we will not get any more packets, and any
715 * that might be being processed will wait for us here, thereby
716 * guaranteeing that no packets go to the tid_tx pending queue any
720 ieee80211_agg_splice_packets(local, tid_tx, tid);
722 /* future packets must not find the tid_tx struct any more */
723 ieee80211_assign_tid_tx(sta, tid, NULL);
725 ieee80211_agg_splice_finish(local, tid);
727 kfree_rcu(tid_tx, rcu_head);
730 spin_unlock_bh(&sta->lock);
731 mutex_unlock(&sta->ampdu_mlme.mtx);
733 mutex_unlock(&local->sta_mtx);
736 void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
737 const u8 *ra, u16 tid)
739 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
740 struct ieee80211_local *local = sdata->local;
741 struct ieee80211_ra_tid *ra_tid;
742 struct sk_buff *skb = dev_alloc_skb(0);
747 ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
748 memcpy(&ra_tid->ra, ra, ETH_ALEN);
751 skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_STOP;
752 skb_queue_tail(&sdata->skb_queue, skb);
753 ieee80211_queue_work(&local->hw, &sdata->work);
755 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
758 void ieee80211_process_addba_resp(struct ieee80211_local *local,
759 struct sta_info *sta,
760 struct ieee80211_mgmt *mgmt,
763 struct tid_ampdu_tx *tid_tx;
767 capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
768 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
769 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
771 mutex_lock(&sta->ampdu_mlme.mtx);
773 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
777 if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
778 #ifdef CONFIG_MAC80211_HT_DEBUG
779 printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
784 del_timer(&tid_tx->addba_resp_timer);
786 #ifdef CONFIG_MAC80211_HT_DEBUG
787 printk(KERN_DEBUG "switched off addBA timer for tid %d\n", tid);
790 * IEEE 802.11-2007 7.3.1.14:
791 * In an ADDBA Response frame, when the Status Code field
792 * is set to 0, the Buffer Size subfield is set to a value
795 if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
796 == WLAN_STATUS_SUCCESS && buf_size) {
797 if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
799 /* ignore duplicate response */
803 tid_tx->buf_size = buf_size;
805 if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
806 ieee80211_agg_tx_operational(local, sta, tid);
808 sta->ampdu_mlme.addba_req_num[tid] = 0;
811 mod_timer(&tid_tx->session_timer,
812 TU_TO_EXP_TIME(tid_tx->timeout));
815 ___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR,
820 mutex_unlock(&sta->ampdu_mlme.mtx);