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 <net/mac80211.h>
19 #include "ieee80211_i.h"
20 #include "driver-ops.h"
24 * DOC: TX A-MPDU aggregation
26 * Aggregation on the TX side requires setting the hardware flag
27 * %IEEE80211_HW_AMPDU_AGGREGATION. The driver will then be handed
28 * packets with a flag indicating A-MPDU aggregation. The driver
29 * or device is responsible for actually aggregating the frames,
30 * as well as deciding how many and which to aggregate.
32 * When TX aggregation is started by some subsystem (usually the rate
33 * control algorithm would be appropriate) by calling the
34 * ieee80211_start_tx_ba_session() function, the driver will be
35 * notified via its @ampdu_action function, with the
36 * %IEEE80211_AMPDU_TX_START action.
38 * In response to that, the driver is later required to call the
39 * ieee80211_start_tx_ba_cb_irqsafe() function, which will really
40 * start the aggregation session after the peer has also responded.
41 * If the peer responds negatively, the session will be stopped
42 * again right away. Note that it is possible for the aggregation
43 * session to be stopped before the driver has indicated that it
44 * is done setting it up, in which case it must not indicate the
47 * Also note that, since we also need to wait for a response from
48 * the peer, the driver is notified of the completion of the
49 * handshake by the %IEEE80211_AMPDU_TX_OPERATIONAL action to the
50 * @ampdu_action callback.
52 * Similarly, when the aggregation session is stopped by the peer
53 * or something calling ieee80211_stop_tx_ba_session(), the driver's
54 * @ampdu_action function will be called with the action
55 * %IEEE80211_AMPDU_TX_STOP. In this case, the call must not fail,
56 * and the driver must later call ieee80211_stop_tx_ba_cb_irqsafe().
59 static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
60 const u8 *da, u16 tid,
61 u8 dialog_token, u16 start_seq_num,
62 u16 agg_size, u16 timeout)
64 struct ieee80211_local *local = sdata->local;
66 struct ieee80211_mgmt *mgmt;
69 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
72 printk(KERN_ERR "%s: failed to allocate buffer "
73 "for addba request frame\n", sdata->name);
76 skb_reserve(skb, local->hw.extra_tx_headroom);
77 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
79 memcpy(mgmt->da, da, ETH_ALEN);
80 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
81 if (sdata->vif.type == NL80211_IFTYPE_AP ||
82 sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
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_sub_if_data *sdata, u8 *ra, u16 tid, u16 ssn)
111 struct ieee80211_local *local = sdata->local;
113 struct ieee80211_bar *bar;
116 skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
118 printk(KERN_ERR "%s: failed to allocate buffer for "
119 "bar frame\n", sdata->name);
122 skb_reserve(skb, local->hw.extra_tx_headroom);
123 bar = (struct ieee80211_bar *)skb_put(skb, sizeof(*bar));
124 memset(bar, 0, sizeof(*bar));
125 bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
126 IEEE80211_STYPE_BACK_REQ);
127 memcpy(bar->ra, ra, ETH_ALEN);
128 memcpy(bar->ta, sdata->vif.addr, ETH_ALEN);
129 bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
130 bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
131 bar_control |= (u16)(tid << 12);
132 bar->control = cpu_to_le16(bar_control);
133 bar->start_seq_num = cpu_to_le16(ssn);
135 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
136 ieee80211_tx_skb(sdata, skb);
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 static void kfree_tid_tx(struct rcu_head *rcu_head)
149 struct tid_ampdu_tx *tid_tx =
150 container_of(rcu_head, struct tid_ampdu_tx, rcu_head);
155 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
156 enum ieee80211_back_parties initiator,
159 struct ieee80211_local *local = sta->local;
160 struct tid_ampdu_tx *tid_tx = sta->ampdu_mlme.tid_tx[tid];
163 lockdep_assert_held(&sta->ampdu_mlme.mtx);
168 spin_lock_bh(&sta->lock);
170 if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
171 /* not even started yet! */
172 ieee80211_assign_tid_tx(sta, tid, NULL);
173 spin_unlock_bh(&sta->lock);
174 call_rcu(&tid_tx->rcu_head, kfree_tid_tx);
178 spin_unlock_bh(&sta->lock);
180 #ifdef CONFIG_MAC80211_HT_DEBUG
181 printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
183 #endif /* CONFIG_MAC80211_HT_DEBUG */
185 set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
187 del_timer_sync(&tid_tx->addba_resp_timer);
190 * After this packets are no longer handed right through
191 * to the driver but are put onto tid_tx->pending instead,
192 * with locking to ensure proper access.
194 clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
196 tid_tx->stop_initiator = initiator;
197 tid_tx->tx_stop = tx;
199 ret = drv_ampdu_action(local, sta->sdata,
200 IEEE80211_AMPDU_TX_STOP,
201 &sta->sta, tid, NULL, 0);
203 /* HW shall not deny going back to legacy */
206 * We may have pending packets get stuck in this case...
207 * Not bothering with a workaround for now.
215 * After sending add Block Ack request we activated a timer until
216 * add Block Ack response will arrive from the recipient.
217 * If this timer expires sta_addba_resp_timer_expired will be executed.
219 static void sta_addba_resp_timer_expired(unsigned long data)
221 /* not an elegant detour, but there is no choice as the timer passes
222 * only one argument, and both sta_info and TID are needed, so init
223 * flow in sta_info_create gives the TID as data, while the timer_to_id
224 * array gives the sta through container_of */
225 u16 tid = *(u8 *)data;
226 struct sta_info *sta = container_of((void *)data,
227 struct sta_info, timer_to_tid[tid]);
228 struct tid_ampdu_tx *tid_tx;
230 /* check if the TID waits for addBA response */
232 tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
234 test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
236 #ifdef CONFIG_MAC80211_HT_DEBUG
237 printk(KERN_DEBUG "timer expired on tid %d but we are not "
238 "(or no longer) expecting addBA response there\n",
244 #ifdef CONFIG_MAC80211_HT_DEBUG
245 printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
248 ieee80211_stop_tx_ba_session(&sta->sta, tid);
252 static inline int ieee80211_ac_from_tid(int tid)
254 return ieee802_1d_to_ac[tid & 7];
258 * When multiple aggregation sessions on multiple stations
259 * are being created/destroyed simultaneously, we need to
260 * refcount the global queue stop caused by that in order
261 * to not get into a situation where one of the aggregation
262 * setup or teardown re-enables queues before the other is
263 * ready to handle that.
265 * These two functions take care of this issue by keeping
266 * a global "agg_queue_stop" refcount.
268 static void __acquires(agg_queue)
269 ieee80211_stop_queue_agg(struct ieee80211_local *local, int tid)
271 int queue = ieee80211_ac_from_tid(tid);
273 if (atomic_inc_return(&local->agg_queue_stop[queue]) == 1)
274 ieee80211_stop_queue_by_reason(
276 IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
277 __acquire(agg_queue);
280 static void __releases(agg_queue)
281 ieee80211_wake_queue_agg(struct ieee80211_local *local, int tid)
283 int queue = ieee80211_ac_from_tid(tid);
285 if (atomic_dec_return(&local->agg_queue_stop[queue]) == 0)
286 ieee80211_wake_queue_by_reason(
288 IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
289 __release(agg_queue);
292 void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
294 struct tid_ampdu_tx *tid_tx = sta->ampdu_mlme.tid_tx[tid];
295 struct ieee80211_local *local = sta->local;
296 struct ieee80211_sub_if_data *sdata = sta->sdata;
300 lockdep_assert_held(&sta->ampdu_mlme.mtx);
303 * While we're asking the driver about the aggregation,
304 * stop the AC queue so that we don't have to worry
305 * about frames that came in while we were doing that,
306 * which would require us to put them to the AC pending
307 * afterwards which just makes the code more complex.
309 ieee80211_stop_queue_agg(local, tid);
311 clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
314 * make sure no packets are being processed to get
315 * valid starting sequence number
319 start_seq_num = sta->tid_seq[tid] >> 4;
321 ret = drv_ampdu_action(local, sdata, IEEE80211_AMPDU_TX_START,
322 &sta->sta, tid, &start_seq_num, 0);
324 #ifdef CONFIG_MAC80211_HT_DEBUG
325 printk(KERN_DEBUG "BA request denied - HW unavailable for"
328 spin_lock_bh(&sta->lock);
329 ieee80211_assign_tid_tx(sta, tid, NULL);
330 spin_unlock_bh(&sta->lock);
332 ieee80211_wake_queue_agg(local, tid);
333 call_rcu(&tid_tx->rcu_head, kfree_tid_tx);
337 /* we can take packets again now */
338 ieee80211_wake_queue_agg(local, tid);
340 /* activate the timer for the recipient's addBA response */
341 mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
342 #ifdef CONFIG_MAC80211_HT_DEBUG
343 printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
346 spin_lock_bh(&sta->lock);
347 sta->ampdu_mlme.addba_req_num[tid]++;
348 spin_unlock_bh(&sta->lock);
350 /* send AddBA request */
351 ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
352 tid_tx->dialog_token, start_seq_num,
353 local->hw.max_tx_aggregation_subframes,
357 int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
360 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
361 struct ieee80211_sub_if_data *sdata = sta->sdata;
362 struct ieee80211_local *local = sdata->local;
363 struct tid_ampdu_tx *tid_tx;
366 trace_api_start_tx_ba_session(pubsta, tid);
368 if (WARN_ON(!local->ops->ampdu_action))
371 if ((tid >= STA_TID_NUM) ||
372 !(local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION))
375 #ifdef CONFIG_MAC80211_HT_DEBUG
376 printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
378 #endif /* CONFIG_MAC80211_HT_DEBUG */
381 * The aggregation code is not prepared to handle
382 * anything but STA/AP due to the BSSID handling.
383 * IBSS could work in the code but isn't supported
384 * by drivers or the standard.
386 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
387 sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
388 sdata->vif.type != NL80211_IFTYPE_AP)
391 if (test_sta_flags(sta, WLAN_STA_BLOCK_BA)) {
392 #ifdef CONFIG_MAC80211_HT_DEBUG
393 printk(KERN_DEBUG "BA sessions blocked. "
394 "Denying BA session request\n");
399 spin_lock_bh(&sta->lock);
401 /* we have tried too many times, receiver does not want A-MPDU */
402 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
407 tid_tx = sta->ampdu_mlme.tid_tx[tid];
408 /* check if the TID is not in aggregation flow already */
409 if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) {
410 #ifdef CONFIG_MAC80211_HT_DEBUG
411 printk(KERN_DEBUG "BA request denied - session is not "
412 "idle on tid %u\n", tid);
413 #endif /* CONFIG_MAC80211_HT_DEBUG */
418 /* prepare A-MPDU MLME for Tx aggregation */
419 tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
421 #ifdef CONFIG_MAC80211_HT_DEBUG
423 printk(KERN_ERR "allocate tx mlme to tid %d failed\n",
430 skb_queue_head_init(&tid_tx->pending);
431 __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
433 tid_tx->timeout = timeout;
436 tid_tx->addba_resp_timer.function = sta_addba_resp_timer_expired;
437 tid_tx->addba_resp_timer.data = (unsigned long)&sta->timer_to_tid[tid];
438 init_timer(&tid_tx->addba_resp_timer);
440 /* assign a dialog token */
441 sta->ampdu_mlme.dialog_token_allocator++;
442 tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
445 * Finally, assign it to the start array; the work item will
446 * collect it and move it to the normal array.
448 sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
450 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
452 /* this flow continues off the work */
454 spin_unlock_bh(&sta->lock);
457 EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
460 * splice packets from the STA's pending to the local pending,
461 * requires a call to ieee80211_agg_splice_finish later
463 static void __acquires(agg_queue)
464 ieee80211_agg_splice_packets(struct ieee80211_local *local,
465 struct tid_ampdu_tx *tid_tx, u16 tid)
467 int queue = ieee80211_ac_from_tid(tid);
470 ieee80211_stop_queue_agg(local, tid);
472 if (WARN(!tid_tx, "TID %d gone but expected when splicing aggregates"
473 " from the pending queue\n", tid))
476 if (!skb_queue_empty(&tid_tx->pending)) {
477 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
478 /* copy over remaining packets */
479 skb_queue_splice_tail_init(&tid_tx->pending,
480 &local->pending[queue]);
481 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
485 static void __releases(agg_queue)
486 ieee80211_agg_splice_finish(struct ieee80211_local *local, u16 tid)
488 ieee80211_wake_queue_agg(local, tid);
491 static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
492 struct sta_info *sta, u16 tid)
494 lockdep_assert_held(&sta->ampdu_mlme.mtx);
496 #ifdef CONFIG_MAC80211_HT_DEBUG
497 printk(KERN_DEBUG "Aggregation is on for tid %d\n", tid);
500 drv_ampdu_action(local, sta->sdata,
501 IEEE80211_AMPDU_TX_OPERATIONAL,
502 &sta->sta, tid, NULL,
503 sta->ampdu_mlme.tid_tx[tid]->buf_size);
506 * synchronize with TX path, while splicing the TX path
507 * should block so it won't put more packets onto pending.
509 spin_lock_bh(&sta->lock);
511 ieee80211_agg_splice_packets(local, sta->ampdu_mlme.tid_tx[tid], tid);
513 * Now mark as operational. This will be visible
514 * in the TX path, and lets it go lock-free in
517 set_bit(HT_AGG_STATE_OPERATIONAL, &sta->ampdu_mlme.tid_tx[tid]->state);
518 ieee80211_agg_splice_finish(local, tid);
520 spin_unlock_bh(&sta->lock);
523 void ieee80211_start_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u16 tid)
525 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
526 struct ieee80211_local *local = sdata->local;
527 struct sta_info *sta;
528 struct tid_ampdu_tx *tid_tx;
530 trace_api_start_tx_ba_cb(sdata, ra, tid);
532 if (tid >= STA_TID_NUM) {
533 #ifdef CONFIG_MAC80211_HT_DEBUG
534 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
540 mutex_lock(&local->sta_mtx);
541 sta = sta_info_get(sdata, ra);
543 mutex_unlock(&local->sta_mtx);
544 #ifdef CONFIG_MAC80211_HT_DEBUG
545 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
550 mutex_lock(&sta->ampdu_mlme.mtx);
551 tid_tx = sta->ampdu_mlme.tid_tx[tid];
553 if (WARN_ON(!tid_tx)) {
554 #ifdef CONFIG_MAC80211_HT_DEBUG
555 printk(KERN_DEBUG "addBA was not requested!\n");
560 if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
563 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
564 ieee80211_agg_tx_operational(local, sta, tid);
567 mutex_unlock(&sta->ampdu_mlme.mtx);
568 mutex_unlock(&local->sta_mtx);
571 void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
572 const u8 *ra, u16 tid)
574 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
575 struct ieee80211_local *local = sdata->local;
576 struct ieee80211_ra_tid *ra_tid;
577 struct sk_buff *skb = dev_alloc_skb(0);
579 if (unlikely(!skb)) {
580 #ifdef CONFIG_MAC80211_HT_DEBUG
582 printk(KERN_WARNING "%s: Not enough memory, "
583 "dropping start BA session", sdata->name);
587 ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
588 memcpy(&ra_tid->ra, ra, ETH_ALEN);
591 skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_START;
592 skb_queue_tail(&sdata->skb_queue, skb);
593 ieee80211_queue_work(&local->hw, &sdata->work);
595 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
597 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
598 enum ieee80211_back_parties initiator,
603 mutex_lock(&sta->ampdu_mlme.mtx);
605 ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator, tx);
607 mutex_unlock(&sta->ampdu_mlme.mtx);
612 int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
614 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
615 struct ieee80211_sub_if_data *sdata = sta->sdata;
616 struct ieee80211_local *local = sdata->local;
617 struct tid_ampdu_tx *tid_tx;
620 trace_api_stop_tx_ba_session(pubsta, tid);
622 if (!local->ops->ampdu_action)
625 if (tid >= STA_TID_NUM)
628 spin_lock_bh(&sta->lock);
629 tid_tx = sta->ampdu_mlme.tid_tx[tid];
636 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
637 /* already in progress stopping it */
642 set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
643 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
646 spin_unlock_bh(&sta->lock);
649 EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
651 void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
653 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
654 struct ieee80211_local *local = sdata->local;
655 struct sta_info *sta;
656 struct tid_ampdu_tx *tid_tx;
658 trace_api_stop_tx_ba_cb(sdata, ra, tid);
660 if (tid >= STA_TID_NUM) {
661 #ifdef CONFIG_MAC80211_HT_DEBUG
662 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
668 #ifdef CONFIG_MAC80211_HT_DEBUG
669 printk(KERN_DEBUG "Stopping Tx BA session for %pM tid %d\n",
671 #endif /* CONFIG_MAC80211_HT_DEBUG */
673 mutex_lock(&local->sta_mtx);
675 sta = sta_info_get(sdata, ra);
677 #ifdef CONFIG_MAC80211_HT_DEBUG
678 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
683 mutex_lock(&sta->ampdu_mlme.mtx);
684 spin_lock_bh(&sta->lock);
685 tid_tx = sta->ampdu_mlme.tid_tx[tid];
687 if (!tid_tx || !test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
688 #ifdef CONFIG_MAC80211_HT_DEBUG
689 printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
694 if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
695 ieee80211_send_delba(sta->sdata, ra, tid,
696 WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
699 * When we get here, the TX path will not be lockless any more wrt.
700 * aggregation, since the OPERATIONAL bit has long been cleared.
701 * Thus it will block on getting the lock, if it occurs. So if we
702 * stop the queue now, we will not get any more packets, and any
703 * that might be being processed will wait for us here, thereby
704 * guaranteeing that no packets go to the tid_tx pending queue any
708 ieee80211_agg_splice_packets(local, tid_tx, tid);
710 /* future packets must not find the tid_tx struct any more */
711 ieee80211_assign_tid_tx(sta, tid, NULL);
713 ieee80211_agg_splice_finish(local, tid);
715 call_rcu(&tid_tx->rcu_head, kfree_tid_tx);
718 spin_unlock_bh(&sta->lock);
719 mutex_unlock(&sta->ampdu_mlme.mtx);
721 mutex_unlock(&local->sta_mtx);
724 void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
725 const u8 *ra, u16 tid)
727 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
728 struct ieee80211_local *local = sdata->local;
729 struct ieee80211_ra_tid *ra_tid;
730 struct sk_buff *skb = dev_alloc_skb(0);
732 if (unlikely(!skb)) {
733 #ifdef CONFIG_MAC80211_HT_DEBUG
735 printk(KERN_WARNING "%s: Not enough memory, "
736 "dropping stop BA session", sdata->name);
740 ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
741 memcpy(&ra_tid->ra, ra, ETH_ALEN);
744 skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_STOP;
745 skb_queue_tail(&sdata->skb_queue, skb);
746 ieee80211_queue_work(&local->hw, &sdata->work);
748 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
751 void ieee80211_process_addba_resp(struct ieee80211_local *local,
752 struct sta_info *sta,
753 struct ieee80211_mgmt *mgmt,
756 struct tid_ampdu_tx *tid_tx;
760 capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
761 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
762 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
764 mutex_lock(&sta->ampdu_mlme.mtx);
766 tid_tx = sta->ampdu_mlme.tid_tx[tid];
770 if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
771 #ifdef CONFIG_MAC80211_HT_DEBUG
772 printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
777 del_timer(&tid_tx->addba_resp_timer);
779 #ifdef CONFIG_MAC80211_HT_DEBUG
780 printk(KERN_DEBUG "switched off addBA timer for tid %d\n", tid);
783 if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
784 == WLAN_STATUS_SUCCESS) {
786 * IEEE 802.11-2007 7.3.1.14:
787 * In an ADDBA Response frame, when the Status Code field
788 * is set to 0, the Buffer Size subfield is set to a value
794 if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
796 /* ignore duplicate response */
800 tid_tx->buf_size = buf_size;
802 if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
803 ieee80211_agg_tx_operational(local, sta, tid);
805 sta->ampdu_mlme.addba_req_num[tid] = 0;
807 ___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR,
812 mutex_unlock(&sta->ampdu_mlme.mtx);