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);
74 skb_reserve(skb, local->hw.extra_tx_headroom);
75 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
77 memcpy(mgmt->da, da, ETH_ALEN);
78 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
79 if (sdata->vif.type == NL80211_IFTYPE_AP ||
80 sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
81 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
82 else if (sdata->vif.type == NL80211_IFTYPE_STATION)
83 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
85 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
86 IEEE80211_STYPE_ACTION);
88 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
90 mgmt->u.action.category = WLAN_CATEGORY_BACK;
91 mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
93 mgmt->u.action.u.addba_req.dialog_token = dialog_token;
94 capab = (u16)(1 << 1); /* bit 1 aggregation policy */
95 capab |= (u16)(tid << 2); /* bit 5:2 TID number */
96 capab |= (u16)(agg_size << 6); /* bit 15:6 max size of aggergation */
98 mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
100 mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
101 mgmt->u.action.u.addba_req.start_seq_num =
102 cpu_to_le16(start_seq_num << 4);
104 ieee80211_tx_skb(sdata, skb);
107 void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn)
109 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
110 struct ieee80211_local *local = sdata->local;
112 struct ieee80211_bar *bar;
115 skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
119 skb_reserve(skb, local->hw.extra_tx_headroom);
120 bar = (struct ieee80211_bar *)skb_put(skb, sizeof(*bar));
121 memset(bar, 0, sizeof(*bar));
122 bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
123 IEEE80211_STYPE_BACK_REQ);
124 memcpy(bar->ra, ra, ETH_ALEN);
125 memcpy(bar->ta, sdata->vif.addr, ETH_ALEN);
126 bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
127 bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
128 bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT);
129 bar->control = cpu_to_le16(bar_control);
130 bar->start_seq_num = cpu_to_le16(ssn);
132 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
133 ieee80211_tx_skb(sdata, skb);
135 EXPORT_SYMBOL(ieee80211_send_bar);
137 void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
138 struct tid_ampdu_tx *tid_tx)
140 lockdep_assert_held(&sta->ampdu_mlme.mtx);
141 lockdep_assert_held(&sta->lock);
142 rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
145 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
146 enum ieee80211_back_parties initiator,
149 struct ieee80211_local *local = sta->local;
150 struct tid_ampdu_tx *tid_tx;
153 lockdep_assert_held(&sta->ampdu_mlme.mtx);
155 spin_lock_bh(&sta->lock);
157 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
159 spin_unlock_bh(&sta->lock);
163 /* if we're already stopping ignore any new requests to stop */
164 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
165 spin_unlock_bh(&sta->lock);
169 if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
170 /* not even started yet! */
171 ieee80211_assign_tid_tx(sta, tid, NULL);
172 spin_unlock_bh(&sta->lock);
173 kfree_rcu(tid_tx, rcu_head);
177 set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
179 spin_unlock_bh(&sta->lock);
181 #ifdef CONFIG_MAC80211_HT_DEBUG
182 printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
184 #endif /* CONFIG_MAC80211_HT_DEBUG */
186 del_timer_sync(&tid_tx->addba_resp_timer);
189 * After this packets are no longer handed right through
190 * to the driver but are put onto tid_tx->pending instead,
191 * with locking to ensure proper access.
193 clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
196 * There might be a few packets being processed right now (on
197 * another CPU) that have already gotten past the aggregation
198 * check when it was still OPERATIONAL and consequently have
199 * IEEE80211_TX_CTL_AMPDU set. In that case, this code might
200 * call into the driver at the same time or even before the
201 * TX paths calls into it, which could confuse the driver.
203 * Wait for all currently running TX paths to finish before
204 * telling the driver. New packets will not go through since
205 * the aggregation session is no longer OPERATIONAL.
209 tid_tx->stop_initiator = initiator;
210 tid_tx->tx_stop = tx;
212 ret = drv_ampdu_action(local, sta->sdata,
213 IEEE80211_AMPDU_TX_STOP,
214 &sta->sta, tid, NULL, 0);
216 /* HW shall not deny going back to legacy */
219 * We may have pending packets get stuck in this case...
220 * Not bothering with a workaround for now.
228 * After sending add Block Ack request we activated a timer until
229 * add Block Ack response will arrive from the recipient.
230 * If this timer expires sta_addba_resp_timer_expired will be executed.
232 static void sta_addba_resp_timer_expired(unsigned long data)
234 /* not an elegant detour, but there is no choice as the timer passes
235 * only one argument, and both sta_info and TID are needed, so init
236 * flow in sta_info_create gives the TID as data, while the timer_to_id
237 * array gives the sta through container_of */
238 u16 tid = *(u8 *)data;
239 struct sta_info *sta = container_of((void *)data,
240 struct sta_info, timer_to_tid[tid]);
241 struct tid_ampdu_tx *tid_tx;
243 /* check if the TID waits for addBA response */
245 tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
247 test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
249 #ifdef CONFIG_MAC80211_HT_DEBUG
250 printk(KERN_DEBUG "timer expired on tid %d but we are not "
251 "(or no longer) expecting addBA response there\n",
257 #ifdef CONFIG_MAC80211_HT_DEBUG
258 printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
261 ieee80211_stop_tx_ba_session(&sta->sta, tid);
265 static inline int ieee80211_ac_from_tid(int tid)
267 return ieee802_1d_to_ac[tid & 7];
271 * When multiple aggregation sessions on multiple stations
272 * are being created/destroyed simultaneously, we need to
273 * refcount the global queue stop caused by that in order
274 * to not get into a situation where one of the aggregation
275 * setup or teardown re-enables queues before the other is
276 * ready to handle that.
278 * These two functions take care of this issue by keeping
279 * a global "agg_queue_stop" refcount.
281 static void __acquires(agg_queue)
282 ieee80211_stop_queue_agg(struct ieee80211_local *local, int tid)
284 int queue = ieee80211_ac_from_tid(tid);
286 if (atomic_inc_return(&local->agg_queue_stop[queue]) == 1)
287 ieee80211_stop_queue_by_reason(
289 IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
290 __acquire(agg_queue);
293 static void __releases(agg_queue)
294 ieee80211_wake_queue_agg(struct ieee80211_local *local, int tid)
296 int queue = ieee80211_ac_from_tid(tid);
298 if (atomic_dec_return(&local->agg_queue_stop[queue]) == 0)
299 ieee80211_wake_queue_by_reason(
301 IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
302 __release(agg_queue);
305 void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
307 struct tid_ampdu_tx *tid_tx;
308 struct ieee80211_local *local = sta->local;
309 struct ieee80211_sub_if_data *sdata = sta->sdata;
313 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
316 * While we're asking the driver about the aggregation,
317 * stop the AC queue so that we don't have to worry
318 * about frames that came in while we were doing that,
319 * which would require us to put them to the AC pending
320 * afterwards which just makes the code more complex.
322 ieee80211_stop_queue_agg(local, tid);
324 clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
327 * make sure no packets are being processed to get
328 * valid starting sequence number
332 start_seq_num = sta->tid_seq[tid] >> 4;
334 ret = drv_ampdu_action(local, sdata, IEEE80211_AMPDU_TX_START,
335 &sta->sta, tid, &start_seq_num, 0);
337 #ifdef CONFIG_MAC80211_HT_DEBUG
338 printk(KERN_DEBUG "BA request denied - HW unavailable for"
341 spin_lock_bh(&sta->lock);
342 ieee80211_assign_tid_tx(sta, tid, NULL);
343 spin_unlock_bh(&sta->lock);
345 ieee80211_wake_queue_agg(local, tid);
346 kfree_rcu(tid_tx, rcu_head);
350 /* we can take packets again now */
351 ieee80211_wake_queue_agg(local, tid);
353 /* activate the timer for the recipient's addBA response */
354 mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
355 #ifdef CONFIG_MAC80211_HT_DEBUG
356 printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
359 spin_lock_bh(&sta->lock);
360 sta->ampdu_mlme.addba_req_num[tid]++;
361 spin_unlock_bh(&sta->lock);
363 /* send AddBA request */
364 ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
365 tid_tx->dialog_token, start_seq_num,
366 local->hw.max_tx_aggregation_subframes,
370 int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
373 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
374 struct ieee80211_sub_if_data *sdata = sta->sdata;
375 struct ieee80211_local *local = sdata->local;
376 struct tid_ampdu_tx *tid_tx;
379 trace_api_start_tx_ba_session(pubsta, tid);
381 if (WARN_ON(!local->ops->ampdu_action))
384 if ((tid >= STA_TID_NUM) ||
385 !(local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) ||
386 (local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW))
389 #ifdef CONFIG_MAC80211_HT_DEBUG
390 printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
392 #endif /* CONFIG_MAC80211_HT_DEBUG */
395 * The aggregation code is not prepared to handle
396 * anything but STA/AP due to the BSSID handling.
397 * IBSS could work in the code but isn't supported
398 * by drivers or the standard.
400 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
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);
449 /* assign a dialog token */
450 sta->ampdu_mlme.dialog_token_allocator++;
451 tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
454 * Finally, assign it to the start array; the work item will
455 * collect it and move it to the normal array.
457 sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
459 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
461 /* this flow continues off the work */
463 spin_unlock_bh(&sta->lock);
466 EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
469 * splice packets from the STA's pending to the local pending,
470 * requires a call to ieee80211_agg_splice_finish later
472 static void __acquires(agg_queue)
473 ieee80211_agg_splice_packets(struct ieee80211_local *local,
474 struct tid_ampdu_tx *tid_tx, u16 tid)
476 int queue = ieee80211_ac_from_tid(tid);
479 ieee80211_stop_queue_agg(local, tid);
481 if (WARN(!tid_tx, "TID %d gone but expected when splicing aggregates"
482 " from the pending queue\n", tid))
485 if (!skb_queue_empty(&tid_tx->pending)) {
486 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
487 /* copy over remaining packets */
488 skb_queue_splice_tail_init(&tid_tx->pending,
489 &local->pending[queue]);
490 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
494 static void __releases(agg_queue)
495 ieee80211_agg_splice_finish(struct ieee80211_local *local, u16 tid)
497 ieee80211_wake_queue_agg(local, tid);
500 static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
501 struct sta_info *sta, u16 tid)
503 struct tid_ampdu_tx *tid_tx;
505 lockdep_assert_held(&sta->ampdu_mlme.mtx);
507 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
509 #ifdef CONFIG_MAC80211_HT_DEBUG
510 printk(KERN_DEBUG "Aggregation is on for tid %d\n", tid);
513 drv_ampdu_action(local, sta->sdata,
514 IEEE80211_AMPDU_TX_OPERATIONAL,
515 &sta->sta, tid, NULL, tid_tx->buf_size);
518 * synchronize with TX path, while splicing the TX path
519 * should block so it won't put more packets onto pending.
521 spin_lock_bh(&sta->lock);
523 ieee80211_agg_splice_packets(local, tid_tx, tid);
525 * Now mark as operational. This will be visible
526 * in the TX path, and lets it go lock-free in
529 set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
530 ieee80211_agg_splice_finish(local, tid);
532 spin_unlock_bh(&sta->lock);
535 void ieee80211_start_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u16 tid)
537 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
538 struct ieee80211_local *local = sdata->local;
539 struct sta_info *sta;
540 struct tid_ampdu_tx *tid_tx;
542 trace_api_start_tx_ba_cb(sdata, ra, tid);
544 if (tid >= STA_TID_NUM) {
545 #ifdef CONFIG_MAC80211_HT_DEBUG
546 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
552 mutex_lock(&local->sta_mtx);
553 sta = sta_info_get(sdata, ra);
555 mutex_unlock(&local->sta_mtx);
556 #ifdef CONFIG_MAC80211_HT_DEBUG
557 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
562 mutex_lock(&sta->ampdu_mlme.mtx);
563 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
565 if (WARN_ON(!tid_tx)) {
566 #ifdef CONFIG_MAC80211_HT_DEBUG
567 printk(KERN_DEBUG "addBA was not requested!\n");
572 if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
575 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
576 ieee80211_agg_tx_operational(local, sta, tid);
579 mutex_unlock(&sta->ampdu_mlme.mtx);
580 mutex_unlock(&local->sta_mtx);
583 void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
584 const u8 *ra, u16 tid)
586 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
587 struct ieee80211_local *local = sdata->local;
588 struct ieee80211_ra_tid *ra_tid;
589 struct sk_buff *skb = dev_alloc_skb(0);
594 ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
595 memcpy(&ra_tid->ra, ra, ETH_ALEN);
598 skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_START;
599 skb_queue_tail(&sdata->skb_queue, skb);
600 ieee80211_queue_work(&local->hw, &sdata->work);
602 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
604 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
605 enum ieee80211_back_parties initiator,
610 mutex_lock(&sta->ampdu_mlme.mtx);
612 ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator, tx);
614 mutex_unlock(&sta->ampdu_mlme.mtx);
619 int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
621 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
622 struct ieee80211_sub_if_data *sdata = sta->sdata;
623 struct ieee80211_local *local = sdata->local;
624 struct tid_ampdu_tx *tid_tx;
627 trace_api_stop_tx_ba_session(pubsta, tid);
629 if (!local->ops->ampdu_action)
632 if (tid >= STA_TID_NUM)
635 spin_lock_bh(&sta->lock);
636 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
643 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
644 /* already in progress stopping it */
649 set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
650 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
653 spin_unlock_bh(&sta->lock);
656 EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
658 void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
660 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
661 struct ieee80211_local *local = sdata->local;
662 struct sta_info *sta;
663 struct tid_ampdu_tx *tid_tx;
665 trace_api_stop_tx_ba_cb(sdata, ra, tid);
667 if (tid >= STA_TID_NUM) {
668 #ifdef CONFIG_MAC80211_HT_DEBUG
669 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
675 #ifdef CONFIG_MAC80211_HT_DEBUG
676 printk(KERN_DEBUG "Stopping Tx BA session for %pM tid %d\n",
678 #endif /* CONFIG_MAC80211_HT_DEBUG */
680 mutex_lock(&local->sta_mtx);
682 sta = sta_info_get(sdata, ra);
684 #ifdef CONFIG_MAC80211_HT_DEBUG
685 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
690 mutex_lock(&sta->ampdu_mlme.mtx);
691 spin_lock_bh(&sta->lock);
692 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
694 if (!tid_tx || !test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
695 #ifdef CONFIG_MAC80211_HT_DEBUG
696 printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
701 if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
702 ieee80211_send_delba(sta->sdata, ra, tid,
703 WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
706 * When we get here, the TX path will not be lockless any more wrt.
707 * aggregation, since the OPERATIONAL bit has long been cleared.
708 * Thus it will block on getting the lock, if it occurs. So if we
709 * stop the queue now, we will not get any more packets, and any
710 * that might be being processed will wait for us here, thereby
711 * guaranteeing that no packets go to the tid_tx pending queue any
715 ieee80211_agg_splice_packets(local, tid_tx, tid);
717 /* future packets must not find the tid_tx struct any more */
718 ieee80211_assign_tid_tx(sta, tid, NULL);
720 ieee80211_agg_splice_finish(local, tid);
722 kfree_rcu(tid_tx, rcu_head);
725 spin_unlock_bh(&sta->lock);
726 mutex_unlock(&sta->ampdu_mlme.mtx);
728 mutex_unlock(&local->sta_mtx);
731 void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
732 const u8 *ra, u16 tid)
734 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
735 struct ieee80211_local *local = sdata->local;
736 struct ieee80211_ra_tid *ra_tid;
737 struct sk_buff *skb = dev_alloc_skb(0);
742 ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
743 memcpy(&ra_tid->ra, ra, ETH_ALEN);
746 skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_STOP;
747 skb_queue_tail(&sdata->skb_queue, skb);
748 ieee80211_queue_work(&local->hw, &sdata->work);
750 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
753 void ieee80211_process_addba_resp(struct ieee80211_local *local,
754 struct sta_info *sta,
755 struct ieee80211_mgmt *mgmt,
758 struct tid_ampdu_tx *tid_tx;
762 capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
763 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
764 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
766 mutex_lock(&sta->ampdu_mlme.mtx);
768 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
772 if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
773 #ifdef CONFIG_MAC80211_HT_DEBUG
774 printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
779 del_timer_sync(&tid_tx->addba_resp_timer);
781 #ifdef CONFIG_MAC80211_HT_DEBUG
782 printk(KERN_DEBUG "switched off addBA timer for tid %d\n", tid);
786 * addba_resp_timer may have fired before we got here, and
787 * caused WANT_STOP to be set. If the stop then was already
788 * processed further, STOPPING might be set.
790 if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) ||
791 test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
792 #ifdef CONFIG_MAC80211_HT_DEBUG
794 "got addBA resp for tid %d but we already gave up\n",
801 * IEEE 802.11-2007 7.3.1.14:
802 * In an ADDBA Response frame, when the Status Code field
803 * is set to 0, the Buffer Size subfield is set to a value
806 if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
807 == WLAN_STATUS_SUCCESS && buf_size) {
808 if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
810 /* ignore duplicate response */
814 tid_tx->buf_size = buf_size;
816 if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
817 ieee80211_agg_tx_operational(local, sta, tid);
819 sta->ampdu_mlme.addba_req_num[tid] = 0;
821 ___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR,
826 mutex_unlock(&sta->ampdu_mlme.mtx);