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().
58 * Note that the sta can get destroyed before the BA tear down is
62 static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
63 const u8 *da, u16 tid,
64 u8 dialog_token, u16 start_seq_num,
65 u16 agg_size, u16 timeout)
67 struct ieee80211_local *local = sdata->local;
69 struct ieee80211_mgmt *mgmt;
72 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
77 skb_reserve(skb, local->hw.extra_tx_headroom);
78 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
80 memcpy(mgmt->da, da, ETH_ALEN);
81 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
82 if (sdata->vif.type == NL80211_IFTYPE_AP ||
83 sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
84 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
85 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
86 else if (sdata->vif.type == NL80211_IFTYPE_STATION)
87 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
88 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
89 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
91 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
92 IEEE80211_STYPE_ACTION);
94 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
96 mgmt->u.action.category = WLAN_CATEGORY_BACK;
97 mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
99 mgmt->u.action.u.addba_req.dialog_token = dialog_token;
100 capab = (u16)(1 << 1); /* bit 1 aggregation policy */
101 capab |= (u16)(tid << 2); /* bit 5:2 TID number */
102 capab |= (u16)(agg_size << 6); /* bit 15:6 max size of aggergation */
104 mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
106 mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
107 mgmt->u.action.u.addba_req.start_seq_num =
108 cpu_to_le16(start_seq_num << 4);
110 ieee80211_tx_skb(sdata, skb);
113 void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn)
115 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
116 struct ieee80211_local *local = sdata->local;
118 struct ieee80211_bar *bar;
121 skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
125 skb_reserve(skb, local->hw.extra_tx_headroom);
126 bar = (struct ieee80211_bar *)skb_put(skb, sizeof(*bar));
127 memset(bar, 0, sizeof(*bar));
128 bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
129 IEEE80211_STYPE_BACK_REQ);
130 memcpy(bar->ra, ra, ETH_ALEN);
131 memcpy(bar->ta, sdata->vif.addr, ETH_ALEN);
132 bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
133 bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
134 bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT);
135 bar->control = cpu_to_le16(bar_control);
136 bar->start_seq_num = cpu_to_le16(ssn);
138 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
139 ieee80211_tx_skb(sdata, skb);
141 EXPORT_SYMBOL(ieee80211_send_bar);
143 void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
144 struct tid_ampdu_tx *tid_tx)
146 lockdep_assert_held(&sta->ampdu_mlme.mtx);
147 lockdep_assert_held(&sta->lock);
148 rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
151 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
152 enum ieee80211_back_parties initiator,
155 struct ieee80211_local *local = sta->local;
156 struct tid_ampdu_tx *tid_tx;
159 lockdep_assert_held(&sta->ampdu_mlme.mtx);
161 spin_lock_bh(&sta->lock);
163 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
165 spin_unlock_bh(&sta->lock);
169 /* if we're already stopping ignore any new requests to stop */
170 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
171 spin_unlock_bh(&sta->lock);
175 if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
176 /* not even started yet! */
177 ieee80211_assign_tid_tx(sta, tid, NULL);
178 spin_unlock_bh(&sta->lock);
179 kfree_rcu(tid_tx, rcu_head);
183 set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
185 spin_unlock_bh(&sta->lock);
187 #ifdef CONFIG_MAC80211_HT_DEBUG
188 printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
190 #endif /* CONFIG_MAC80211_HT_DEBUG */
192 del_timer_sync(&tid_tx->addba_resp_timer);
193 del_timer_sync(&tid_tx->session_timer);
196 * After this packets are no longer handed right through
197 * to the driver but are put onto tid_tx->pending instead,
198 * with locking to ensure proper access.
200 clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
203 * There might be a few packets being processed right now (on
204 * another CPU) that have already gotten past the aggregation
205 * check when it was still OPERATIONAL and consequently have
206 * IEEE80211_TX_CTL_AMPDU set. In that case, this code might
207 * call into the driver at the same time or even before the
208 * TX paths calls into it, which could confuse the driver.
210 * Wait for all currently running TX paths to finish before
211 * telling the driver. New packets will not go through since
212 * the aggregation session is no longer OPERATIONAL.
216 tid_tx->stop_initiator = initiator;
217 tid_tx->tx_stop = tx;
219 ret = drv_ampdu_action(local, sta->sdata,
220 IEEE80211_AMPDU_TX_STOP,
221 &sta->sta, tid, NULL, 0);
223 /* HW shall not deny going back to legacy */
226 * We may have pending packets get stuck in this case...
227 * Not bothering with a workaround for now.
235 * After sending add Block Ack request we activated a timer until
236 * add Block Ack response will arrive from the recipient.
237 * If this timer expires sta_addba_resp_timer_expired will be executed.
239 static void sta_addba_resp_timer_expired(unsigned long data)
241 /* not an elegant detour, but there is no choice as the timer passes
242 * only one argument, and both sta_info and TID are needed, so init
243 * flow in sta_info_create gives the TID as data, while the timer_to_id
244 * array gives the sta through container_of */
245 u16 tid = *(u8 *)data;
246 struct sta_info *sta = container_of((void *)data,
247 struct sta_info, timer_to_tid[tid]);
248 struct tid_ampdu_tx *tid_tx;
250 /* check if the TID waits for addBA response */
252 tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
254 test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
256 #ifdef CONFIG_MAC80211_HT_DEBUG
257 printk(KERN_DEBUG "timer expired on tid %d but we are not "
258 "(or no longer) expecting addBA response there\n",
264 #ifdef CONFIG_MAC80211_HT_DEBUG
265 printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
268 ieee80211_stop_tx_ba_session(&sta->sta, tid);
272 static inline int ieee80211_ac_from_tid(int tid)
274 return ieee802_1d_to_ac[tid & 7];
278 * When multiple aggregation sessions on multiple stations
279 * are being created/destroyed simultaneously, we need to
280 * refcount the global queue stop caused by that in order
281 * to not get into a situation where one of the aggregation
282 * setup or teardown re-enables queues before the other is
283 * ready to handle that.
285 * These two functions take care of this issue by keeping
286 * a global "agg_queue_stop" refcount.
288 static void __acquires(agg_queue)
289 ieee80211_stop_queue_agg(struct ieee80211_local *local, int tid)
291 int queue = ieee80211_ac_from_tid(tid);
293 if (atomic_inc_return(&local->agg_queue_stop[queue]) == 1)
294 ieee80211_stop_queue_by_reason(
296 IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
297 __acquire(agg_queue);
300 static void __releases(agg_queue)
301 ieee80211_wake_queue_agg(struct ieee80211_local *local, int tid)
303 int queue = ieee80211_ac_from_tid(tid);
305 if (atomic_dec_return(&local->agg_queue_stop[queue]) == 0)
306 ieee80211_wake_queue_by_reason(
308 IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
309 __release(agg_queue);
312 void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
314 struct tid_ampdu_tx *tid_tx;
315 struct ieee80211_local *local = sta->local;
316 struct ieee80211_sub_if_data *sdata = sta->sdata;
320 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
323 * While we're asking the driver about the aggregation,
324 * stop the AC queue so that we don't have to worry
325 * about frames that came in while we were doing that,
326 * which would require us to put them to the AC pending
327 * afterwards which just makes the code more complex.
329 ieee80211_stop_queue_agg(local, tid);
331 clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
334 * make sure no packets are being processed to get
335 * valid starting sequence number
339 start_seq_num = sta->tid_seq[tid] >> 4;
341 ret = drv_ampdu_action(local, sdata, IEEE80211_AMPDU_TX_START,
342 &sta->sta, tid, &start_seq_num, 0);
344 #ifdef CONFIG_MAC80211_HT_DEBUG
345 printk(KERN_DEBUG "BA request denied - HW unavailable for"
348 spin_lock_bh(&sta->lock);
349 ieee80211_assign_tid_tx(sta, tid, NULL);
350 spin_unlock_bh(&sta->lock);
352 ieee80211_wake_queue_agg(local, tid);
353 kfree_rcu(tid_tx, rcu_head);
357 /* we can take packets again now */
358 ieee80211_wake_queue_agg(local, tid);
360 /* activate the timer for the recipient's addBA response */
361 mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
362 #ifdef CONFIG_MAC80211_HT_DEBUG
363 printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
366 spin_lock_bh(&sta->lock);
367 sta->ampdu_mlme.addba_req_num[tid]++;
368 spin_unlock_bh(&sta->lock);
370 /* send AddBA request */
371 ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
372 tid_tx->dialog_token, start_seq_num,
373 local->hw.max_tx_aggregation_subframes,
378 * After accepting the AddBA Response we activated a timer,
379 * resetting it after each frame that we send.
381 static void sta_tx_agg_session_timer_expired(unsigned long data)
383 /* not an elegant detour, but there is no choice as the timer passes
384 * only one argument, and various sta_info are needed here, so init
385 * flow in sta_info_create gives the TID as data, while the timer_to_id
386 * array gives the sta through container_of */
387 u8 *ptid = (u8 *)data;
388 u8 *timer_to_id = ptid - *ptid;
389 struct sta_info *sta = container_of(timer_to_id, struct sta_info,
392 #ifdef CONFIG_MAC80211_HT_DEBUG
393 printk(KERN_DEBUG "tx session timer expired on tid %d\n", (u16)*ptid);
396 ieee80211_stop_tx_ba_session(&sta->sta, *ptid);
399 int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
402 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
403 struct ieee80211_sub_if_data *sdata = sta->sdata;
404 struct ieee80211_local *local = sdata->local;
405 struct tid_ampdu_tx *tid_tx;
408 trace_api_start_tx_ba_session(pubsta, tid);
410 if (WARN_ON(!local->ops->ampdu_action))
413 if ((tid >= STA_TID_NUM) ||
414 !(local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION) ||
415 (local->hw.flags & IEEE80211_HW_TX_AMPDU_SETUP_IN_HW))
418 #ifdef CONFIG_MAC80211_HT_DEBUG
419 printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
421 #endif /* CONFIG_MAC80211_HT_DEBUG */
423 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
424 sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
425 sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
426 sdata->vif.type != NL80211_IFTYPE_AP &&
427 sdata->vif.type != NL80211_IFTYPE_ADHOC)
430 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
431 #ifdef CONFIG_MAC80211_HT_DEBUG
432 printk(KERN_DEBUG "BA sessions blocked. "
433 "Denying BA session request\n");
439 * 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a
440 * member of an IBSS, and has no other existing Block Ack agreement
441 * with the recipient STA, then the initiating STA shall transmit a
442 * Probe Request frame to the recipient STA and shall not transmit an
443 * ADDBA Request frame unless it receives a Probe Response frame
444 * from the recipient within dot11ADDBAFailureTimeout.
446 * The probe request mechanism for ADDBA is currently not implemented,
447 * but we only build up Block Ack session with HT STAs. This information
448 * is set when we receive a bss info from a probe response or a beacon.
450 if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC &&
451 !sta->sta.ht_cap.ht_supported) {
452 #ifdef CONFIG_MAC80211_HT_DEBUG
453 printk(KERN_DEBUG "BA request denied - IBSS STA %pM"
454 "does not advertise HT support\n", pubsta->addr);
455 #endif /* CONFIG_MAC80211_HT_DEBUG */
459 spin_lock_bh(&sta->lock);
461 /* we have tried too many times, receiver does not want A-MPDU */
462 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
467 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
468 /* check if the TID is not in aggregation flow already */
469 if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) {
470 #ifdef CONFIG_MAC80211_HT_DEBUG
471 printk(KERN_DEBUG "BA request denied - session is not "
472 "idle on tid %u\n", tid);
473 #endif /* CONFIG_MAC80211_HT_DEBUG */
478 /* prepare A-MPDU MLME for Tx aggregation */
479 tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
485 skb_queue_head_init(&tid_tx->pending);
486 __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
488 tid_tx->timeout = timeout;
491 tid_tx->addba_resp_timer.function = sta_addba_resp_timer_expired;
492 tid_tx->addba_resp_timer.data = (unsigned long)&sta->timer_to_tid[tid];
493 init_timer(&tid_tx->addba_resp_timer);
496 tid_tx->session_timer.function = sta_tx_agg_session_timer_expired;
497 tid_tx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid];
498 init_timer(&tid_tx->session_timer);
500 /* assign a dialog token */
501 sta->ampdu_mlme.dialog_token_allocator++;
502 tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
505 * Finally, assign it to the start array; the work item will
506 * collect it and move it to the normal array.
508 sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
510 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
512 /* this flow continues off the work */
514 spin_unlock_bh(&sta->lock);
517 EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
520 * splice packets from the STA's pending to the local pending,
521 * requires a call to ieee80211_agg_splice_finish later
523 static void __acquires(agg_queue)
524 ieee80211_agg_splice_packets(struct ieee80211_local *local,
525 struct tid_ampdu_tx *tid_tx, u16 tid)
527 int queue = ieee80211_ac_from_tid(tid);
530 ieee80211_stop_queue_agg(local, tid);
532 if (WARN(!tid_tx, "TID %d gone but expected when splicing aggregates"
533 " from the pending queue\n", tid))
536 if (!skb_queue_empty(&tid_tx->pending)) {
537 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
538 /* copy over remaining packets */
539 skb_queue_splice_tail_init(&tid_tx->pending,
540 &local->pending[queue]);
541 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
545 static void __releases(agg_queue)
546 ieee80211_agg_splice_finish(struct ieee80211_local *local, u16 tid)
548 ieee80211_wake_queue_agg(local, tid);
551 static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
552 struct sta_info *sta, u16 tid)
554 struct tid_ampdu_tx *tid_tx;
556 lockdep_assert_held(&sta->ampdu_mlme.mtx);
558 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
560 #ifdef CONFIG_MAC80211_HT_DEBUG
561 printk(KERN_DEBUG "Aggregation is on for tid %d\n", tid);
564 drv_ampdu_action(local, sta->sdata,
565 IEEE80211_AMPDU_TX_OPERATIONAL,
566 &sta->sta, tid, NULL, tid_tx->buf_size);
569 * synchronize with TX path, while splicing the TX path
570 * should block so it won't put more packets onto pending.
572 spin_lock_bh(&sta->lock);
574 ieee80211_agg_splice_packets(local, tid_tx, tid);
576 * Now mark as operational. This will be visible
577 * in the TX path, and lets it go lock-free in
580 set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
581 ieee80211_agg_splice_finish(local, tid);
583 spin_unlock_bh(&sta->lock);
586 void ieee80211_start_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u16 tid)
588 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
589 struct ieee80211_local *local = sdata->local;
590 struct sta_info *sta;
591 struct tid_ampdu_tx *tid_tx;
593 trace_api_start_tx_ba_cb(sdata, ra, tid);
595 if (tid >= STA_TID_NUM) {
596 #ifdef CONFIG_MAC80211_HT_DEBUG
597 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
603 mutex_lock(&local->sta_mtx);
604 sta = sta_info_get_bss(sdata, ra);
606 mutex_unlock(&local->sta_mtx);
607 #ifdef CONFIG_MAC80211_HT_DEBUG
608 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
613 mutex_lock(&sta->ampdu_mlme.mtx);
614 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
616 if (WARN_ON(!tid_tx)) {
617 #ifdef CONFIG_MAC80211_HT_DEBUG
618 printk(KERN_DEBUG "addBA was not requested!\n");
623 if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
626 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
627 ieee80211_agg_tx_operational(local, sta, tid);
630 mutex_unlock(&sta->ampdu_mlme.mtx);
631 mutex_unlock(&local->sta_mtx);
634 void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
635 const u8 *ra, u16 tid)
637 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
638 struct ieee80211_local *local = sdata->local;
639 struct ieee80211_ra_tid *ra_tid;
640 struct sk_buff *skb = dev_alloc_skb(0);
645 ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
646 memcpy(&ra_tid->ra, ra, ETH_ALEN);
649 skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_START;
650 skb_queue_tail(&sdata->skb_queue, skb);
651 ieee80211_queue_work(&local->hw, &sdata->work);
653 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
655 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
656 enum ieee80211_back_parties initiator,
661 mutex_lock(&sta->ampdu_mlme.mtx);
663 ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator, tx);
665 mutex_unlock(&sta->ampdu_mlme.mtx);
670 int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
672 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
673 struct ieee80211_sub_if_data *sdata = sta->sdata;
674 struct ieee80211_local *local = sdata->local;
675 struct tid_ampdu_tx *tid_tx;
678 trace_api_stop_tx_ba_session(pubsta, tid);
680 if (!local->ops->ampdu_action)
683 if (tid >= STA_TID_NUM)
686 spin_lock_bh(&sta->lock);
687 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
694 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
695 /* already in progress stopping it */
700 set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
701 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
704 spin_unlock_bh(&sta->lock);
707 EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
709 void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
711 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
712 struct ieee80211_local *local = sdata->local;
713 struct sta_info *sta;
714 struct tid_ampdu_tx *tid_tx;
716 trace_api_stop_tx_ba_cb(sdata, ra, tid);
718 if (tid >= STA_TID_NUM) {
719 #ifdef CONFIG_MAC80211_HT_DEBUG
720 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
726 #ifdef CONFIG_MAC80211_HT_DEBUG
727 printk(KERN_DEBUG "Stopping Tx BA session for %pM tid %d\n",
729 #endif /* CONFIG_MAC80211_HT_DEBUG */
731 mutex_lock(&local->sta_mtx);
733 sta = sta_info_get_bss(sdata, ra);
735 #ifdef CONFIG_MAC80211_HT_DEBUG
736 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
741 mutex_lock(&sta->ampdu_mlme.mtx);
742 spin_lock_bh(&sta->lock);
743 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
745 if (!tid_tx || !test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
746 #ifdef CONFIG_MAC80211_HT_DEBUG
747 printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
752 if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
753 ieee80211_send_delba(sta->sdata, ra, tid,
754 WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
757 * When we get here, the TX path will not be lockless any more wrt.
758 * aggregation, since the OPERATIONAL bit has long been cleared.
759 * Thus it will block on getting the lock, if it occurs. So if we
760 * stop the queue now, we will not get any more packets, and any
761 * that might be being processed will wait for us here, thereby
762 * guaranteeing that no packets go to the tid_tx pending queue any
766 ieee80211_agg_splice_packets(local, tid_tx, tid);
768 /* future packets must not find the tid_tx struct any more */
769 ieee80211_assign_tid_tx(sta, tid, NULL);
771 ieee80211_agg_splice_finish(local, tid);
773 kfree_rcu(tid_tx, rcu_head);
776 spin_unlock_bh(&sta->lock);
777 mutex_unlock(&sta->ampdu_mlme.mtx);
779 mutex_unlock(&local->sta_mtx);
782 void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
783 const u8 *ra, u16 tid)
785 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
786 struct ieee80211_local *local = sdata->local;
787 struct ieee80211_ra_tid *ra_tid;
788 struct sk_buff *skb = dev_alloc_skb(0);
793 ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
794 memcpy(&ra_tid->ra, ra, ETH_ALEN);
797 skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_STOP;
798 skb_queue_tail(&sdata->skb_queue, skb);
799 ieee80211_queue_work(&local->hw, &sdata->work);
801 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
804 void ieee80211_process_addba_resp(struct ieee80211_local *local,
805 struct sta_info *sta,
806 struct ieee80211_mgmt *mgmt,
809 struct tid_ampdu_tx *tid_tx;
813 capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
814 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
815 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
817 mutex_lock(&sta->ampdu_mlme.mtx);
819 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
823 if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
824 #ifdef CONFIG_MAC80211_HT_DEBUG
825 printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
830 del_timer_sync(&tid_tx->addba_resp_timer);
832 #ifdef CONFIG_MAC80211_HT_DEBUG
833 printk(KERN_DEBUG "switched off addBA timer for tid %d\n", tid);
837 * addba_resp_timer may have fired before we got here, and
838 * caused WANT_STOP to be set. If the stop then was already
839 * processed further, STOPPING might be set.
841 if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) ||
842 test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
843 #ifdef CONFIG_MAC80211_HT_DEBUG
845 "got addBA resp for tid %d but we already gave up\n",
852 * IEEE 802.11-2007 7.3.1.14:
853 * In an ADDBA Response frame, when the Status Code field
854 * is set to 0, the Buffer Size subfield is set to a value
857 if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
858 == WLAN_STATUS_SUCCESS && buf_size) {
859 if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
861 /* ignore duplicate response */
865 tid_tx->buf_size = buf_size;
867 if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
868 ieee80211_agg_tx_operational(local, sta, tid);
870 sta->ampdu_mlme.addba_req_num[tid] = 0;
873 mod_timer(&tid_tx->session_timer,
874 TU_TO_EXP_TIME(tid_tx->timeout));
877 ___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR,
882 mutex_unlock(&sta->ampdu_mlme.mtx);