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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * HT handling
4 *
5 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
6 * Copyright 2002-2005, Instant802 Networks, Inc.
7 * Copyright 2005-2006, Devicescape Software, Inc.
8 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
9 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
10 * Copyright 2007-2010, Intel Corporation
11 * Copyright(c) 2015-2017 Intel Deutschland GmbH
12 * Copyright (C) 2018 - 2020 Intel Corporation
13 */
14
15#include <linux/ieee80211.h>
16#include <linux/slab.h>
17#include <linux/export.h>
18#include <net/mac80211.h>
19#include "ieee80211_i.h"
20#include "driver-ops.h"
21#include "wme.h"
22
23/**
24 * DOC: TX A-MPDU aggregation
25 *
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.
31 *
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.
37 *
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
45 * setup completion.
46 *
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.
51 *
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().
57 * Note that the sta can get destroyed before the BA tear down is
58 * complete.
59 */
60
61static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
62 const u8 *da, u16 tid,
63 u8 dialog_token, u16 start_seq_num,
64 u16 agg_size, u16 timeout)
65{
66 struct ieee80211_local *local = sdata->local;
67 struct sk_buff *skb;
68 struct ieee80211_mgmt *mgmt;
69 u16 capab;
70
71 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
72
73 if (!skb)
74 return;
75
76 skb_reserve(skb, local->hw.extra_tx_headroom);
77 mgmt = skb_put_zero(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);
86 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
87 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
88
89 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
90 IEEE80211_STYPE_ACTION);
91
92 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
93
94 mgmt->u.action.category = WLAN_CATEGORY_BACK;
95 mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
96
97 mgmt->u.action.u.addba_req.dialog_token = dialog_token;
98 capab = IEEE80211_ADDBA_PARAM_AMSDU_MASK;
99 capab |= IEEE80211_ADDBA_PARAM_POLICY_MASK;
100 capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
101 capab |= u16_encode_bits(agg_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
102
103 mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
104
105 mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
106 mgmt->u.action.u.addba_req.start_seq_num =
107 cpu_to_le16(start_seq_num << 4);
108
109 ieee80211_tx_skb(sdata, skb);
110}
111
112void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn)
113{
114 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
115 struct ieee80211_local *local = sdata->local;
116 struct sk_buff *skb;
117 struct ieee80211_bar *bar;
118 u16 bar_control = 0;
119
120 skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
121 if (!skb)
122 return;
123
124 skb_reserve(skb, local->hw.extra_tx_headroom);
125 bar = skb_put_zero(skb, sizeof(*bar));
126 bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
127 IEEE80211_STYPE_BACK_REQ);
128 memcpy(bar->ra, ra, ETH_ALEN);
129 memcpy(bar->ta, sdata->vif.addr, ETH_ALEN);
130 bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
131 bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
132 bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT);
133 bar->control = cpu_to_le16(bar_control);
134 bar->start_seq_num = cpu_to_le16(ssn);
135
136 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
137 IEEE80211_TX_CTL_REQ_TX_STATUS;
138 ieee80211_tx_skb_tid(sdata, skb, tid);
139}
140EXPORT_SYMBOL(ieee80211_send_bar);
141
142void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
143 struct tid_ampdu_tx *tid_tx)
144{
145 lockdep_assert_held(&sta->ampdu_mlme.mtx);
146 lockdep_assert_held(&sta->lock);
147 rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
148}
149
150/*
151 * When multiple aggregation sessions on multiple stations
152 * are being created/destroyed simultaneously, we need to
153 * refcount the global queue stop caused by that in order
154 * to not get into a situation where one of the aggregation
155 * setup or teardown re-enables queues before the other is
156 * ready to handle that.
157 *
158 * These two functions take care of this issue by keeping
159 * a global "agg_queue_stop" refcount.
160 */
161static void __acquires(agg_queue)
162ieee80211_stop_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
163{
164 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
165
166 /* we do refcounting here, so don't use the queue reason refcounting */
167
168 if (atomic_inc_return(&sdata->local->agg_queue_stop[queue]) == 1)
169 ieee80211_stop_queue_by_reason(
170 &sdata->local->hw, queue,
171 IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
172 false);
173 __acquire(agg_queue);
174}
175
176static void __releases(agg_queue)
177ieee80211_wake_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
178{
179 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
180
181 if (atomic_dec_return(&sdata->local->agg_queue_stop[queue]) == 0)
182 ieee80211_wake_queue_by_reason(
183 &sdata->local->hw, queue,
184 IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
185 false);
186 __release(agg_queue);
187}
188
189static void
190ieee80211_agg_stop_txq(struct sta_info *sta, int tid)
191{
192 struct ieee80211_txq *txq = sta->sta.txq[tid];
193 struct ieee80211_sub_if_data *sdata;
194 struct fq *fq;
195 struct txq_info *txqi;
196
197 if (!txq)
198 return;
199
200 txqi = to_txq_info(txq);
201 sdata = vif_to_sdata(txq->vif);
202 fq = &sdata->local->fq;
203
204 /* Lock here to protect against further seqno updates on dequeue */
205 spin_lock_bh(&fq->lock);
206 set_bit(IEEE80211_TXQ_STOP, &txqi->flags);
207 spin_unlock_bh(&fq->lock);
208}
209
210static void
211ieee80211_agg_start_txq(struct sta_info *sta, int tid, bool enable)
212{
213 struct ieee80211_txq *txq = sta->sta.txq[tid];
214 struct txq_info *txqi;
215
216 if (!txq)
217 return;
218
219 txqi = to_txq_info(txq);
220
221 if (enable)
222 set_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
223 else
224 clear_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
225
226 clear_bit(IEEE80211_TXQ_STOP, &txqi->flags);
227 local_bh_disable();
228 rcu_read_lock();
229 schedule_and_wake_txq(sta->sdata->local, txqi);
230 rcu_read_unlock();
231 local_bh_enable();
232}
233
234/*
235 * splice packets from the STA's pending to the local pending,
236 * requires a call to ieee80211_agg_splice_finish later
237 */
238static void __acquires(agg_queue)
239ieee80211_agg_splice_packets(struct ieee80211_sub_if_data *sdata,
240 struct tid_ampdu_tx *tid_tx, u16 tid)
241{
242 struct ieee80211_local *local = sdata->local;
243 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
244 unsigned long flags;
245
246 ieee80211_stop_queue_agg(sdata, tid);
247
248 if (WARN(!tid_tx,
249 "TID %d gone but expected when splicing aggregates from the pending queue\n",
250 tid))
251 return;
252
253 if (!skb_queue_empty(&tid_tx->pending)) {
254 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
255 /* copy over remaining packets */
256 skb_queue_splice_tail_init(&tid_tx->pending,
257 &local->pending[queue]);
258 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
259 }
260}
261
262static void __releases(agg_queue)
263ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid)
264{
265 ieee80211_wake_queue_agg(sdata, tid);
266}
267
268static void ieee80211_remove_tid_tx(struct sta_info *sta, int tid)
269{
270 struct tid_ampdu_tx *tid_tx;
271
272 lockdep_assert_held(&sta->ampdu_mlme.mtx);
273 lockdep_assert_held(&sta->lock);
274
275 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
276
277 /*
278 * When we get here, the TX path will not be lockless any more wrt.
279 * aggregation, since the OPERATIONAL bit has long been cleared.
280 * Thus it will block on getting the lock, if it occurs. So if we
281 * stop the queue now, we will not get any more packets, and any
282 * that might be being processed will wait for us here, thereby
283 * guaranteeing that no packets go to the tid_tx pending queue any
284 * more.
285 */
286
287 ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
288
289 /* future packets must not find the tid_tx struct any more */
290 ieee80211_assign_tid_tx(sta, tid, NULL);
291
292 ieee80211_agg_splice_finish(sta->sdata, tid);
293 ieee80211_agg_start_txq(sta, tid, false);
294
295 kfree_rcu(tid_tx, rcu_head);
296}
297
298int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
299 enum ieee80211_agg_stop_reason reason)
300{
301 struct ieee80211_local *local = sta->local;
302 struct tid_ampdu_tx *tid_tx;
303 struct ieee80211_ampdu_params params = {
304 .sta = &sta->sta,
305 .tid = tid,
306 .buf_size = 0,
307 .amsdu = false,
308 .timeout = 0,
309 .ssn = 0,
310 };
311 int ret;
312
313 lockdep_assert_held(&sta->ampdu_mlme.mtx);
314
315 switch (reason) {
316 case AGG_STOP_DECLINED:
317 case AGG_STOP_LOCAL_REQUEST:
318 case AGG_STOP_PEER_REQUEST:
319 params.action = IEEE80211_AMPDU_TX_STOP_CONT;
320 break;
321 case AGG_STOP_DESTROY_STA:
322 params.action = IEEE80211_AMPDU_TX_STOP_FLUSH;
323 break;
324 default:
325 WARN_ON_ONCE(1);
326 return -EINVAL;
327 }
328
329 spin_lock_bh(&sta->lock);
330
331 /* free struct pending for start, if present */
332 tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
333 kfree(tid_tx);
334 sta->ampdu_mlme.tid_start_tx[tid] = NULL;
335
336 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
337 if (!tid_tx) {
338 spin_unlock_bh(&sta->lock);
339 return -ENOENT;
340 }
341
342 /*
343 * if we're already stopping ignore any new requests to stop
344 * unless we're destroying it in which case notify the driver
345 */
346 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
347 spin_unlock_bh(&sta->lock);
348 if (reason != AGG_STOP_DESTROY_STA)
349 return -EALREADY;
350 params.action = IEEE80211_AMPDU_TX_STOP_FLUSH_CONT;
351 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
352 WARN_ON_ONCE(ret);
353 return 0;
354 }
355
356 if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
357 /* not even started yet! */
358 ieee80211_assign_tid_tx(sta, tid, NULL);
359 spin_unlock_bh(&sta->lock);
360 kfree_rcu(tid_tx, rcu_head);
361 return 0;
362 }
363
364 set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
365
366 ieee80211_agg_stop_txq(sta, tid);
367
368 spin_unlock_bh(&sta->lock);
369
370 ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n",
371 sta->sta.addr, tid);
372
373 del_timer_sync(&tid_tx->addba_resp_timer);
374 del_timer_sync(&tid_tx->session_timer);
375
376 /*
377 * After this packets are no longer handed right through
378 * to the driver but are put onto tid_tx->pending instead,
379 * with locking to ensure proper access.
380 */
381 clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
382
383 /*
384 * There might be a few packets being processed right now (on
385 * another CPU) that have already gotten past the aggregation
386 * check when it was still OPERATIONAL and consequently have
387 * IEEE80211_TX_CTL_AMPDU set. In that case, this code might
388 * call into the driver at the same time or even before the
389 * TX paths calls into it, which could confuse the driver.
390 *
391 * Wait for all currently running TX paths to finish before
392 * telling the driver. New packets will not go through since
393 * the aggregation session is no longer OPERATIONAL.
394 */
395 if (!local->in_reconfig)
396 synchronize_net();
397
398 tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ?
399 WLAN_BACK_RECIPIENT :
400 WLAN_BACK_INITIATOR;
401 tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST;
402
403 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
404
405 /* HW shall not deny going back to legacy */
406 if (WARN_ON(ret)) {
407 /*
408 * We may have pending packets get stuck in this case...
409 * Not bothering with a workaround for now.
410 */
411 }
412
413 /*
414 * In the case of AGG_STOP_DESTROY_STA, the driver won't
415 * necessarily call ieee80211_stop_tx_ba_cb(), so this may
416 * seem like we can leave the tid_tx data pending forever.
417 * This is true, in a way, but "forever" is only until the
418 * station struct is actually destroyed. In the meantime,
419 * leaving it around ensures that we don't transmit packets
420 * to the driver on this TID which might confuse it.
421 */
422
423 return 0;
424}
425
426/*
427 * After sending add Block Ack request we activated a timer until
428 * add Block Ack response will arrive from the recipient.
429 * If this timer expires sta_addba_resp_timer_expired will be executed.
430 */
431static void sta_addba_resp_timer_expired(struct timer_list *t)
432{
433 struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, addba_resp_timer);
434 struct sta_info *sta = tid_tx->sta;
435 u8 tid = tid_tx->tid;
436
437 /* check if the TID waits for addBA response */
438 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
439 ht_dbg(sta->sdata,
440 "timer expired on %pM tid %d not expecting addBA response\n",
441 sta->sta.addr, tid);
442 return;
443 }
444
445 ht_dbg(sta->sdata, "addBA response timer expired on %pM tid %d\n",
446 sta->sta.addr, tid);
447
448 ieee80211_stop_tx_ba_session(&sta->sta, tid);
449}
450
451static void ieee80211_send_addba_with_timeout(struct sta_info *sta,
452 struct tid_ampdu_tx *tid_tx)
453{
454 struct ieee80211_sub_if_data *sdata = sta->sdata;
455 struct ieee80211_local *local = sta->local;
456 u8 tid = tid_tx->tid;
457 u16 buf_size;
458
459 /* activate the timer for the recipient's addBA response */
460 mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
461 ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n",
462 sta->sta.addr, tid);
463
464 spin_lock_bh(&sta->lock);
465 sta->ampdu_mlme.last_addba_req_time[tid] = jiffies;
466 sta->ampdu_mlme.addba_req_num[tid]++;
467 spin_unlock_bh(&sta->lock);
468
469 if (sta->sta.he_cap.has_he) {
470 buf_size = local->hw.max_tx_aggregation_subframes;
471 } else {
472 /*
473 * We really should use what the driver told us it will
474 * transmit as the maximum, but certain APs (e.g. the
475 * LinkSys WRT120N with FW v1.0.07 build 002 Jun 18 2012)
476 * will crash when we use a lower number.
477 */
478 buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
479 }
480
481 /* send AddBA request */
482 ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
483 tid_tx->dialog_token,
484 sta->tid_seq[tid] >> 4,
485 buf_size, tid_tx->timeout);
486
487 WARN_ON(test_and_set_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state));
488}
489
490void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
491{
492 struct tid_ampdu_tx *tid_tx;
493 struct ieee80211_local *local = sta->local;
494 struct ieee80211_sub_if_data *sdata = sta->sdata;
495 struct ieee80211_ampdu_params params = {
496 .sta = &sta->sta,
497 .action = IEEE80211_AMPDU_TX_START,
498 .tid = tid,
499 .buf_size = 0,
500 .amsdu = false,
501 .timeout = 0,
502 };
503 int ret;
504
505 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
506
507 /*
508 * Start queuing up packets for this aggregation session.
509 * We're going to release them once the driver is OK with
510 * that.
511 */
512 clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
513
514 ieee80211_agg_stop_txq(sta, tid);
515
516 /*
517 * Make sure no packets are being processed. This ensures that
518 * we have a valid starting sequence number and that in-flight
519 * packets have been flushed out and no packets for this TID
520 * will go into the driver during the ampdu_action call.
521 */
522 synchronize_net();
523
524 params.ssn = sta->tid_seq[tid] >> 4;
525 ret = drv_ampdu_action(local, sdata, ¶ms);
526 if (ret == IEEE80211_AMPDU_TX_START_DELAY_ADDBA) {
527 return;
528 } else if (ret == IEEE80211_AMPDU_TX_START_IMMEDIATE) {
529 /*
530 * We didn't send the request yet, so don't need to check
531 * here if we already got a response, just mark as driver
532 * ready immediately.
533 */
534 set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state);
535 } else if (ret) {
536 ht_dbg(sdata,
537 "BA request denied - HW unavailable for %pM tid %d\n",
538 sta->sta.addr, tid);
539 spin_lock_bh(&sta->lock);
540 ieee80211_agg_splice_packets(sdata, tid_tx, tid);
541 ieee80211_assign_tid_tx(sta, tid, NULL);
542 ieee80211_agg_splice_finish(sdata, tid);
543 spin_unlock_bh(&sta->lock);
544
545 ieee80211_agg_start_txq(sta, tid, false);
546
547 kfree_rcu(tid_tx, rcu_head);
548 return;
549 }
550
551 ieee80211_send_addba_with_timeout(sta, tid_tx);
552}
553
554/*
555 * After accepting the AddBA Response we activated a timer,
556 * resetting it after each frame that we send.
557 */
558static void sta_tx_agg_session_timer_expired(struct timer_list *t)
559{
560 struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, session_timer);
561 struct sta_info *sta = tid_tx->sta;
562 u8 tid = tid_tx->tid;
563 unsigned long timeout;
564
565 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
566 return;
567 }
568
569 timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout);
570 if (time_is_after_jiffies(timeout)) {
571 mod_timer(&tid_tx->session_timer, timeout);
572 return;
573 }
574
575 ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n",
576 sta->sta.addr, tid);
577
578 ieee80211_stop_tx_ba_session(&sta->sta, tid);
579}
580
581int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
582 u16 timeout)
583{
584 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
585 struct ieee80211_sub_if_data *sdata = sta->sdata;
586 struct ieee80211_local *local = sdata->local;
587 struct tid_ampdu_tx *tid_tx;
588 int ret = 0;
589
590 trace_api_start_tx_ba_session(pubsta, tid);
591
592 if (WARN(sta->reserved_tid == tid,
593 "Requested to start BA session on reserved tid=%d", tid))
594 return -EINVAL;
595
596 if (!pubsta->ht_cap.ht_supported &&
597 sta->sdata->vif.bss_conf.chandef.chan->band != NL80211_BAND_6GHZ)
598 return -EINVAL;
599
600 if (WARN_ON_ONCE(!local->ops->ampdu_action))
601 return -EINVAL;
602
603 if ((tid >= IEEE80211_NUM_TIDS) ||
604 !ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) ||
605 ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW))
606 return -EINVAL;
607
608 if (WARN_ON(tid >= IEEE80211_FIRST_TSPEC_TSID))
609 return -EINVAL;
610
611 ht_dbg(sdata, "Open BA session requested for %pM tid %u\n",
612 pubsta->addr, tid);
613
614 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
615 sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
616 sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
617 sdata->vif.type != NL80211_IFTYPE_AP &&
618 sdata->vif.type != NL80211_IFTYPE_ADHOC)
619 return -EINVAL;
620
621 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
622 ht_dbg(sdata,
623 "BA sessions blocked - Denying BA session request %pM tid %d\n",
624 sta->sta.addr, tid);
625 return -EINVAL;
626 }
627
628 /*
629 * 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a
630 * member of an IBSS, and has no other existing Block Ack agreement
631 * with the recipient STA, then the initiating STA shall transmit a
632 * Probe Request frame to the recipient STA and shall not transmit an
633 * ADDBA Request frame unless it receives a Probe Response frame
634 * from the recipient within dot11ADDBAFailureTimeout.
635 *
636 * The probe request mechanism for ADDBA is currently not implemented,
637 * but we only build up Block Ack session with HT STAs. This information
638 * is set when we receive a bss info from a probe response or a beacon.
639 */
640 if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC &&
641 !sta->sta.ht_cap.ht_supported) {
642 ht_dbg(sdata,
643 "BA request denied - IBSS STA %pM does not advertise HT support\n",
644 pubsta->addr);
645 return -EINVAL;
646 }
647
648 spin_lock_bh(&sta->lock);
649
650 /* we have tried too many times, receiver does not want A-MPDU */
651 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
652 ret = -EBUSY;
653 goto err_unlock_sta;
654 }
655
656 /*
657 * if we have tried more than HT_AGG_BURST_RETRIES times we
658 * will spread our requests in time to avoid stalling connection
659 * for too long
660 */
661 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES &&
662 time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] +
663 HT_AGG_RETRIES_PERIOD)) {
664 ht_dbg(sdata,
665 "BA request denied - %d failed requests on %pM tid %u\n",
666 sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid);
667 ret = -EBUSY;
668 goto err_unlock_sta;
669 }
670
671 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
672 /* check if the TID is not in aggregation flow already */
673 if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) {
674 ht_dbg(sdata,
675 "BA request denied - session is not idle on %pM tid %u\n",
676 sta->sta.addr, tid);
677 ret = -EAGAIN;
678 goto err_unlock_sta;
679 }
680
681 /* prepare A-MPDU MLME for Tx aggregation */
682 tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
683 if (!tid_tx) {
684 ret = -ENOMEM;
685 goto err_unlock_sta;
686 }
687
688 skb_queue_head_init(&tid_tx->pending);
689 __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
690
691 tid_tx->timeout = timeout;
692 tid_tx->sta = sta;
693 tid_tx->tid = tid;
694
695 /* response timer */
696 timer_setup(&tid_tx->addba_resp_timer, sta_addba_resp_timer_expired, 0);
697
698 /* tx timer */
699 timer_setup(&tid_tx->session_timer,
700 sta_tx_agg_session_timer_expired, TIMER_DEFERRABLE);
701
702 /* assign a dialog token */
703 sta->ampdu_mlme.dialog_token_allocator++;
704 tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
705
706 /*
707 * Finally, assign it to the start array; the work item will
708 * collect it and move it to the normal array.
709 */
710 sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
711
712 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
713
714 /* this flow continues off the work */
715 err_unlock_sta:
716 spin_unlock_bh(&sta->lock);
717 return ret;
718}
719EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
720
721static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
722 struct sta_info *sta, u16 tid)
723{
724 struct tid_ampdu_tx *tid_tx;
725 struct ieee80211_ampdu_params params = {
726 .sta = &sta->sta,
727 .action = IEEE80211_AMPDU_TX_OPERATIONAL,
728 .tid = tid,
729 .timeout = 0,
730 .ssn = 0,
731 };
732
733 lockdep_assert_held(&sta->ampdu_mlme.mtx);
734
735 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
736 params.buf_size = tid_tx->buf_size;
737 params.amsdu = tid_tx->amsdu;
738
739 ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n",
740 sta->sta.addr, tid);
741
742 drv_ampdu_action(local, sta->sdata, ¶ms);
743
744 /*
745 * synchronize with TX path, while splicing the TX path
746 * should block so it won't put more packets onto pending.
747 */
748 spin_lock_bh(&sta->lock);
749
750 ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
751 /*
752 * Now mark as operational. This will be visible
753 * in the TX path, and lets it go lock-free in
754 * the common case.
755 */
756 set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
757 ieee80211_agg_splice_finish(sta->sdata, tid);
758
759 spin_unlock_bh(&sta->lock);
760
761 ieee80211_agg_start_txq(sta, tid, true);
762}
763
764void ieee80211_start_tx_ba_cb(struct sta_info *sta, int tid,
765 struct tid_ampdu_tx *tid_tx)
766{
767 struct ieee80211_sub_if_data *sdata = sta->sdata;
768 struct ieee80211_local *local = sdata->local;
769
770 if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
771 return;
772
773 if (!test_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state)) {
774 ieee80211_send_addba_with_timeout(sta, tid_tx);
775 /* RESPONSE_RECEIVED state whould trigger the flow again */
776 return;
777 }
778
779 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
780 ieee80211_agg_tx_operational(local, sta, tid);
781}
782
783static struct tid_ampdu_tx *
784ieee80211_lookup_tid_tx(struct ieee80211_sub_if_data *sdata,
785 const u8 *ra, u16 tid, struct sta_info **sta)
786{
787 struct tid_ampdu_tx *tid_tx;
788
789 if (tid >= IEEE80211_NUM_TIDS) {
790 ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n",
791 tid, IEEE80211_NUM_TIDS);
792 return NULL;
793 }
794
795 *sta = sta_info_get_bss(sdata, ra);
796 if (!*sta) {
797 ht_dbg(sdata, "Could not find station: %pM\n", ra);
798 return NULL;
799 }
800
801 tid_tx = rcu_dereference((*sta)->ampdu_mlme.tid_tx[tid]);
802
803 if (WARN_ON(!tid_tx))
804 ht_dbg(sdata, "addBA was not requested!\n");
805
806 return tid_tx;
807}
808
809void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
810 const u8 *ra, u16 tid)
811{
812 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
813 struct ieee80211_local *local = sdata->local;
814 struct sta_info *sta;
815 struct tid_ampdu_tx *tid_tx;
816
817 trace_api_start_tx_ba_cb(sdata, ra, tid);
818
819 rcu_read_lock();
820 tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
821 if (!tid_tx)
822 goto out;
823
824 set_bit(HT_AGG_STATE_START_CB, &tid_tx->state);
825 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
826 out:
827 rcu_read_unlock();
828}
829EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
830
831int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
832 enum ieee80211_agg_stop_reason reason)
833{
834 int ret;
835
836 mutex_lock(&sta->ampdu_mlme.mtx);
837
838 ret = ___ieee80211_stop_tx_ba_session(sta, tid, reason);
839
840 mutex_unlock(&sta->ampdu_mlme.mtx);
841
842 return ret;
843}
844
845int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
846{
847 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
848 struct ieee80211_sub_if_data *sdata = sta->sdata;
849 struct ieee80211_local *local = sdata->local;
850 struct tid_ampdu_tx *tid_tx;
851 int ret = 0;
852
853 trace_api_stop_tx_ba_session(pubsta, tid);
854
855 if (!local->ops->ampdu_action)
856 return -EINVAL;
857
858 if (tid >= IEEE80211_NUM_TIDS)
859 return -EINVAL;
860
861 spin_lock_bh(&sta->lock);
862 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
863
864 if (!tid_tx) {
865 ret = -ENOENT;
866 goto unlock;
867 }
868
869 WARN(sta->reserved_tid == tid,
870 "Requested to stop BA session on reserved tid=%d", tid);
871
872 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
873 /* already in progress stopping it */
874 ret = 0;
875 goto unlock;
876 }
877
878 set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
879 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
880
881 unlock:
882 spin_unlock_bh(&sta->lock);
883 return ret;
884}
885EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
886
887void ieee80211_stop_tx_ba_cb(struct sta_info *sta, int tid,
888 struct tid_ampdu_tx *tid_tx)
889{
890 struct ieee80211_sub_if_data *sdata = sta->sdata;
891 bool send_delba = false;
892
893 ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n",
894 sta->sta.addr, tid);
895
896 spin_lock_bh(&sta->lock);
897
898 if (!test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
899 ht_dbg(sdata,
900 "unexpected callback to A-MPDU stop for %pM tid %d\n",
901 sta->sta.addr, tid);
902 goto unlock_sta;
903 }
904
905 if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
906 send_delba = true;
907
908 ieee80211_remove_tid_tx(sta, tid);
909
910 unlock_sta:
911 spin_unlock_bh(&sta->lock);
912
913 if (send_delba)
914 ieee80211_send_delba(sdata, sta->sta.addr, tid,
915 WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
916}
917
918void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
919 const u8 *ra, u16 tid)
920{
921 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
922 struct ieee80211_local *local = sdata->local;
923 struct sta_info *sta;
924 struct tid_ampdu_tx *tid_tx;
925
926 trace_api_stop_tx_ba_cb(sdata, ra, tid);
927
928 rcu_read_lock();
929 tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
930 if (!tid_tx)
931 goto out;
932
933 set_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state);
934 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
935 out:
936 rcu_read_unlock();
937}
938EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
939
940
941void ieee80211_process_addba_resp(struct ieee80211_local *local,
942 struct sta_info *sta,
943 struct ieee80211_mgmt *mgmt,
944 size_t len)
945{
946 struct tid_ampdu_tx *tid_tx;
947 struct ieee80211_txq *txq;
948 u16 capab, tid, buf_size;
949 bool amsdu;
950
951 capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
952 amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK;
953 tid = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_TID_MASK);
954 buf_size = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
955 buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes);
956
957 txq = sta->sta.txq[tid];
958 if (!amsdu && txq)
959 set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags);
960
961 mutex_lock(&sta->ampdu_mlme.mtx);
962
963 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
964 if (!tid_tx)
965 goto out;
966
967 if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
968 ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n",
969 sta->sta.addr, tid);
970 goto out;
971 }
972
973 del_timer_sync(&tid_tx->addba_resp_timer);
974
975 ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n",
976 sta->sta.addr, tid);
977
978 /*
979 * addba_resp_timer may have fired before we got here, and
980 * caused WANT_STOP to be set. If the stop then was already
981 * processed further, STOPPING might be set.
982 */
983 if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) ||
984 test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
985 ht_dbg(sta->sdata,
986 "got addBA resp for %pM tid %d but we already gave up\n",
987 sta->sta.addr, tid);
988 goto out;
989 }
990
991 /*
992 * IEEE 802.11-2007 7.3.1.14:
993 * In an ADDBA Response frame, when the Status Code field
994 * is set to 0, the Buffer Size subfield is set to a value
995 * of at least 1.
996 */
997 if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
998 == WLAN_STATUS_SUCCESS && buf_size) {
999 if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
1000 &tid_tx->state)) {
1001 /* ignore duplicate response */
1002 goto out;
1003 }
1004
1005 tid_tx->buf_size = buf_size;
1006 tid_tx->amsdu = amsdu;
1007
1008 if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
1009 ieee80211_agg_tx_operational(local, sta, tid);
1010
1011 sta->ampdu_mlme.addba_req_num[tid] = 0;
1012
1013 tid_tx->timeout =
1014 le16_to_cpu(mgmt->u.action.u.addba_resp.timeout);
1015
1016 if (tid_tx->timeout) {
1017 mod_timer(&tid_tx->session_timer,
1018 TU_TO_EXP_TIME(tid_tx->timeout));
1019 tid_tx->last_tx = jiffies;
1020 }
1021
1022 } else {
1023 ___ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED);
1024 }
1025
1026 out:
1027 mutex_unlock(&sta->ampdu_mlme.mtx);
1028}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * HT handling
4 *
5 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
6 * Copyright 2002-2005, Instant802 Networks, Inc.
7 * Copyright 2005-2006, Devicescape Software, Inc.
8 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
9 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
10 * Copyright 2007-2010, Intel Corporation
11 * Copyright(c) 2015-2017 Intel Deutschland GmbH
12 * Copyright (C) 2018 - 2023 Intel Corporation
13 */
14
15#include <linux/ieee80211.h>
16#include <linux/slab.h>
17#include <linux/export.h>
18#include <net/mac80211.h>
19#include "ieee80211_i.h"
20#include "driver-ops.h"
21#include "wme.h"
22
23/**
24 * DOC: TX A-MPDU aggregation
25 *
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.
31 *
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.
37 *
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
45 * setup completion.
46 *
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.
51 *
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().
57 * Note that the sta can get destroyed before the BA tear down is
58 * complete.
59 */
60
61static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
62 const u8 *da, u16 tid,
63 u8 dialog_token, u16 start_seq_num,
64 u16 agg_size, u16 timeout)
65{
66 struct ieee80211_local *local = sdata->local;
67 struct sk_buff *skb;
68 struct ieee80211_mgmt *mgmt;
69 u16 capab;
70
71 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
72
73 if (!skb)
74 return;
75
76 skb_reserve(skb, local->hw.extra_tx_headroom);
77 mgmt = skb_put_zero(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->vif.cfg.ap_addr, ETH_ALEN);
86 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
87 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
88
89 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
90 IEEE80211_STYPE_ACTION);
91
92 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
93
94 mgmt->u.action.category = WLAN_CATEGORY_BACK;
95 mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
96
97 mgmt->u.action.u.addba_req.dialog_token = dialog_token;
98 capab = IEEE80211_ADDBA_PARAM_AMSDU_MASK;
99 capab |= IEEE80211_ADDBA_PARAM_POLICY_MASK;
100 capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
101 capab |= u16_encode_bits(agg_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
102
103 mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
104
105 mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
106 mgmt->u.action.u.addba_req.start_seq_num =
107 cpu_to_le16(start_seq_num << 4);
108
109 ieee80211_tx_skb_tid(sdata, skb, tid, -1);
110}
111
112void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn)
113{
114 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
115 struct ieee80211_local *local = sdata->local;
116 struct sk_buff *skb;
117 struct ieee80211_bar *bar;
118 u16 bar_control = 0;
119
120 skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
121 if (!skb)
122 return;
123
124 skb_reserve(skb, local->hw.extra_tx_headroom);
125 bar = skb_put_zero(skb, sizeof(*bar));
126 bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
127 IEEE80211_STYPE_BACK_REQ);
128 memcpy(bar->ra, ra, ETH_ALEN);
129 memcpy(bar->ta, sdata->vif.addr, ETH_ALEN);
130 bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
131 bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
132 bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT);
133 bar->control = cpu_to_le16(bar_control);
134 bar->start_seq_num = cpu_to_le16(ssn);
135
136 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
137 IEEE80211_TX_CTL_REQ_TX_STATUS;
138 ieee80211_tx_skb_tid(sdata, skb, tid, -1);
139}
140EXPORT_SYMBOL(ieee80211_send_bar);
141
142void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
143 struct tid_ampdu_tx *tid_tx)
144{
145 lockdep_assert_wiphy(sta->local->hw.wiphy);
146 lockdep_assert_held(&sta->lock);
147 rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
148}
149
150/*
151 * When multiple aggregation sessions on multiple stations
152 * are being created/destroyed simultaneously, we need to
153 * refcount the global queue stop caused by that in order
154 * to not get into a situation where one of the aggregation
155 * setup or teardown re-enables queues before the other is
156 * ready to handle that.
157 *
158 * These two functions take care of this issue by keeping
159 * a global "agg_queue_stop" refcount.
160 */
161static void __acquires(agg_queue)
162ieee80211_stop_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
163{
164 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
165
166 /* we do refcounting here, so don't use the queue reason refcounting */
167
168 if (atomic_inc_return(&sdata->local->agg_queue_stop[queue]) == 1)
169 ieee80211_stop_queue_by_reason(
170 &sdata->local->hw, queue,
171 IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
172 false);
173 __acquire(agg_queue);
174}
175
176static void __releases(agg_queue)
177ieee80211_wake_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
178{
179 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
180
181 if (atomic_dec_return(&sdata->local->agg_queue_stop[queue]) == 0)
182 ieee80211_wake_queue_by_reason(
183 &sdata->local->hw, queue,
184 IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
185 false);
186 __release(agg_queue);
187}
188
189static void
190ieee80211_agg_stop_txq(struct sta_info *sta, int tid)
191{
192 struct ieee80211_txq *txq = sta->sta.txq[tid];
193 struct ieee80211_sub_if_data *sdata;
194 struct fq *fq;
195 struct txq_info *txqi;
196
197 if (!txq)
198 return;
199
200 txqi = to_txq_info(txq);
201 sdata = vif_to_sdata(txq->vif);
202 fq = &sdata->local->fq;
203
204 /* Lock here to protect against further seqno updates on dequeue */
205 spin_lock_bh(&fq->lock);
206 set_bit(IEEE80211_TXQ_STOP, &txqi->flags);
207 spin_unlock_bh(&fq->lock);
208}
209
210static void
211ieee80211_agg_start_txq(struct sta_info *sta, int tid, bool enable)
212{
213 struct ieee80211_txq *txq = sta->sta.txq[tid];
214 struct txq_info *txqi;
215
216 lockdep_assert_wiphy(sta->local->hw.wiphy);
217
218 if (!txq)
219 return;
220
221 txqi = to_txq_info(txq);
222
223 if (enable)
224 set_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
225 else
226 clear_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
227
228 clear_bit(IEEE80211_TXQ_STOP, &txqi->flags);
229 local_bh_disable();
230 rcu_read_lock();
231 schedule_and_wake_txq(sta->sdata->local, txqi);
232 rcu_read_unlock();
233 local_bh_enable();
234}
235
236/*
237 * splice packets from the STA's pending to the local pending,
238 * requires a call to ieee80211_agg_splice_finish later
239 */
240static void __acquires(agg_queue)
241ieee80211_agg_splice_packets(struct ieee80211_sub_if_data *sdata,
242 struct tid_ampdu_tx *tid_tx, u16 tid)
243{
244 struct ieee80211_local *local = sdata->local;
245 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
246 unsigned long flags;
247
248 ieee80211_stop_queue_agg(sdata, tid);
249
250 if (WARN(!tid_tx,
251 "TID %d gone but expected when splicing aggregates from the pending queue\n",
252 tid))
253 return;
254
255 if (!skb_queue_empty(&tid_tx->pending)) {
256 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
257 /* copy over remaining packets */
258 skb_queue_splice_tail_init(&tid_tx->pending,
259 &local->pending[queue]);
260 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
261 }
262}
263
264static void __releases(agg_queue)
265ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid)
266{
267 ieee80211_wake_queue_agg(sdata, tid);
268}
269
270static void ieee80211_remove_tid_tx(struct sta_info *sta, int tid)
271{
272 struct tid_ampdu_tx *tid_tx;
273
274 lockdep_assert_wiphy(sta->local->hw.wiphy);
275 lockdep_assert_held(&sta->lock);
276
277 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
278
279 /*
280 * When we get here, the TX path will not be lockless any more wrt.
281 * aggregation, since the OPERATIONAL bit has long been cleared.
282 * Thus it will block on getting the lock, if it occurs. So if we
283 * stop the queue now, we will not get any more packets, and any
284 * that might be being processed will wait for us here, thereby
285 * guaranteeing that no packets go to the tid_tx pending queue any
286 * more.
287 */
288
289 ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
290
291 /* future packets must not find the tid_tx struct any more */
292 ieee80211_assign_tid_tx(sta, tid, NULL);
293
294 ieee80211_agg_splice_finish(sta->sdata, tid);
295
296 kfree_rcu(tid_tx, rcu_head);
297}
298
299int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
300 enum ieee80211_agg_stop_reason reason)
301{
302 struct ieee80211_local *local = sta->local;
303 struct tid_ampdu_tx *tid_tx;
304 struct ieee80211_ampdu_params params = {
305 .sta = &sta->sta,
306 .tid = tid,
307 .buf_size = 0,
308 .amsdu = false,
309 .timeout = 0,
310 .ssn = 0,
311 };
312 int ret;
313
314 lockdep_assert_wiphy(sta->local->hw.wiphy);
315
316 switch (reason) {
317 case AGG_STOP_DECLINED:
318 case AGG_STOP_LOCAL_REQUEST:
319 case AGG_STOP_PEER_REQUEST:
320 params.action = IEEE80211_AMPDU_TX_STOP_CONT;
321 break;
322 case AGG_STOP_DESTROY_STA:
323 params.action = IEEE80211_AMPDU_TX_STOP_FLUSH;
324 break;
325 default:
326 WARN_ON_ONCE(1);
327 return -EINVAL;
328 }
329
330 spin_lock_bh(&sta->lock);
331
332 /* free struct pending for start, if present */
333 tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
334 kfree(tid_tx);
335 sta->ampdu_mlme.tid_start_tx[tid] = NULL;
336
337 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
338 if (!tid_tx) {
339 spin_unlock_bh(&sta->lock);
340 return -ENOENT;
341 }
342
343 /*
344 * if we're already stopping ignore any new requests to stop
345 * unless we're destroying it in which case notify the driver
346 */
347 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
348 spin_unlock_bh(&sta->lock);
349 if (reason != AGG_STOP_DESTROY_STA)
350 return -EALREADY;
351 params.action = IEEE80211_AMPDU_TX_STOP_FLUSH_CONT;
352 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
353 WARN_ON_ONCE(ret);
354 return 0;
355 }
356
357 if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
358 /* not even started yet! */
359 ieee80211_assign_tid_tx(sta, tid, NULL);
360 spin_unlock_bh(&sta->lock);
361 kfree_rcu(tid_tx, rcu_head);
362 return 0;
363 }
364
365 set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
366
367 ieee80211_agg_stop_txq(sta, tid);
368
369 spin_unlock_bh(&sta->lock);
370
371 ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n",
372 sta->sta.addr, tid);
373
374 del_timer_sync(&tid_tx->addba_resp_timer);
375 del_timer_sync(&tid_tx->session_timer);
376
377 /*
378 * After this packets are no longer handed right through
379 * to the driver but are put onto tid_tx->pending instead,
380 * with locking to ensure proper access.
381 */
382 clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
383
384 /*
385 * There might be a few packets being processed right now (on
386 * another CPU) that have already gotten past the aggregation
387 * check when it was still OPERATIONAL and consequently have
388 * IEEE80211_TX_CTL_AMPDU set. In that case, this code might
389 * call into the driver at the same time or even before the
390 * TX paths calls into it, which could confuse the driver.
391 *
392 * Wait for all currently running TX paths to finish before
393 * telling the driver. New packets will not go through since
394 * the aggregation session is no longer OPERATIONAL.
395 */
396 if (!local->in_reconfig)
397 synchronize_net();
398
399 tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ?
400 WLAN_BACK_RECIPIENT :
401 WLAN_BACK_INITIATOR;
402 tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST;
403
404 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
405
406 /* HW shall not deny going back to legacy */
407 if (WARN_ON(ret)) {
408 /*
409 * We may have pending packets get stuck in this case...
410 * Not bothering with a workaround for now.
411 */
412 }
413
414 /*
415 * In the case of AGG_STOP_DESTROY_STA, the driver won't
416 * necessarily call ieee80211_stop_tx_ba_cb(), so this may
417 * seem like we can leave the tid_tx data pending forever.
418 * This is true, in a way, but "forever" is only until the
419 * station struct is actually destroyed. In the meantime,
420 * leaving it around ensures that we don't transmit packets
421 * to the driver on this TID which might confuse it.
422 */
423
424 return 0;
425}
426
427/*
428 * After sending add Block Ack request we activated a timer until
429 * add Block Ack response will arrive from the recipient.
430 * If this timer expires sta_addba_resp_timer_expired will be executed.
431 */
432static void sta_addba_resp_timer_expired(struct timer_list *t)
433{
434 struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, addba_resp_timer);
435 struct sta_info *sta = tid_tx->sta;
436 u8 tid = tid_tx->tid;
437
438 /* check if the TID waits for addBA response */
439 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
440 ht_dbg(sta->sdata,
441 "timer expired on %pM tid %d not expecting addBA response\n",
442 sta->sta.addr, tid);
443 return;
444 }
445
446 ht_dbg(sta->sdata, "addBA response timer expired on %pM tid %d\n",
447 sta->sta.addr, tid);
448
449 ieee80211_stop_tx_ba_session(&sta->sta, tid);
450}
451
452static void ieee80211_send_addba_with_timeout(struct sta_info *sta,
453 struct tid_ampdu_tx *tid_tx)
454{
455 struct ieee80211_sub_if_data *sdata = sta->sdata;
456 struct ieee80211_local *local = sta->local;
457 u8 tid = tid_tx->tid;
458 u16 buf_size;
459
460 if (WARN_ON_ONCE(test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state) ||
461 test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state)))
462 return;
463
464 lockdep_assert_wiphy(sta->local->hw.wiphy);
465
466 /* activate the timer for the recipient's addBA response */
467 mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
468 ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n",
469 sta->sta.addr, tid);
470
471 spin_lock_bh(&sta->lock);
472 sta->ampdu_mlme.last_addba_req_time[tid] = jiffies;
473 sta->ampdu_mlme.addba_req_num[tid]++;
474 spin_unlock_bh(&sta->lock);
475
476 if (sta->sta.deflink.he_cap.has_he) {
477 buf_size = local->hw.max_tx_aggregation_subframes;
478 } else {
479 /*
480 * We really should use what the driver told us it will
481 * transmit as the maximum, but certain APs (e.g. the
482 * LinkSys WRT120N with FW v1.0.07 build 002 Jun 18 2012)
483 * will crash when we use a lower number.
484 */
485 buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
486 }
487
488 /* send AddBA request */
489 ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
490 tid_tx->dialog_token, tid_tx->ssn,
491 buf_size, tid_tx->timeout);
492
493 WARN_ON(test_and_set_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state));
494}
495
496void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
497{
498 struct tid_ampdu_tx *tid_tx;
499 struct ieee80211_local *local = sta->local;
500 struct ieee80211_sub_if_data *sdata = sta->sdata;
501 struct ieee80211_ampdu_params params = {
502 .sta = &sta->sta,
503 .action = IEEE80211_AMPDU_TX_START,
504 .tid = tid,
505 .buf_size = 0,
506 .amsdu = false,
507 .timeout = 0,
508 };
509 int ret;
510
511 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
512
513 /*
514 * Start queuing up packets for this aggregation session.
515 * We're going to release them once the driver is OK with
516 * that.
517 */
518 clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
519
520 /*
521 * Make sure no packets are being processed. This ensures that
522 * we have a valid starting sequence number and that in-flight
523 * packets have been flushed out and no packets for this TID
524 * will go into the driver during the ampdu_action call.
525 */
526 synchronize_net();
527
528 params.ssn = sta->tid_seq[tid] >> 4;
529 ret = drv_ampdu_action(local, sdata, ¶ms);
530 tid_tx->ssn = params.ssn;
531 if (ret == IEEE80211_AMPDU_TX_START_DELAY_ADDBA) {
532 return;
533 } else if (ret == IEEE80211_AMPDU_TX_START_IMMEDIATE) {
534 /*
535 * We didn't send the request yet, so don't need to check
536 * here if we already got a response, just mark as driver
537 * ready immediately.
538 */
539 set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state);
540 } else if (ret) {
541 ht_dbg(sdata,
542 "BA request denied - HW unavailable for %pM tid %d\n",
543 sta->sta.addr, tid);
544 spin_lock_bh(&sta->lock);
545 ieee80211_agg_splice_packets(sdata, tid_tx, tid);
546 ieee80211_assign_tid_tx(sta, tid, NULL);
547 ieee80211_agg_splice_finish(sdata, tid);
548 spin_unlock_bh(&sta->lock);
549
550 ieee80211_agg_start_txq(sta, tid, false);
551
552 kfree_rcu(tid_tx, rcu_head);
553 return;
554 }
555
556 ieee80211_send_addba_with_timeout(sta, tid_tx);
557}
558
559void ieee80211_refresh_tx_agg_session_timer(struct ieee80211_sta *pubsta,
560 u16 tid)
561{
562 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
563 struct tid_ampdu_tx *tid_tx;
564
565 if (WARN_ON_ONCE(tid >= IEEE80211_NUM_TIDS))
566 return;
567
568 tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
569 if (!tid_tx)
570 return;
571
572 tid_tx->last_tx = jiffies;
573}
574EXPORT_SYMBOL(ieee80211_refresh_tx_agg_session_timer);
575
576/*
577 * After accepting the AddBA Response we activated a timer,
578 * resetting it after each frame that we send.
579 */
580static void sta_tx_agg_session_timer_expired(struct timer_list *t)
581{
582 struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, session_timer);
583 struct sta_info *sta = tid_tx->sta;
584 u8 tid = tid_tx->tid;
585 unsigned long timeout;
586
587 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
588 return;
589 }
590
591 timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout);
592 if (time_is_after_jiffies(timeout)) {
593 mod_timer(&tid_tx->session_timer, timeout);
594 return;
595 }
596
597 ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n",
598 sta->sta.addr, tid);
599
600 ieee80211_stop_tx_ba_session(&sta->sta, tid);
601}
602
603int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
604 u16 timeout)
605{
606 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
607 struct ieee80211_sub_if_data *sdata = sta->sdata;
608 struct ieee80211_local *local = sdata->local;
609 struct tid_ampdu_tx *tid_tx;
610 int ret = 0;
611
612 trace_api_start_tx_ba_session(pubsta, tid);
613
614 if (WARN(sta->reserved_tid == tid,
615 "Requested to start BA session on reserved tid=%d", tid))
616 return -EINVAL;
617
618 if (!pubsta->deflink.ht_cap.ht_supported &&
619 sta->sdata->vif.bss_conf.chanreq.oper.chan->band != NL80211_BAND_6GHZ)
620 return -EINVAL;
621
622 if (WARN_ON_ONCE(!local->ops->ampdu_action))
623 return -EINVAL;
624
625 if ((tid >= IEEE80211_NUM_TIDS) ||
626 !ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) ||
627 ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW))
628 return -EINVAL;
629
630 if (WARN_ON(tid >= IEEE80211_FIRST_TSPEC_TSID))
631 return -EINVAL;
632
633 ht_dbg(sdata, "Open BA session requested for %pM tid %u\n",
634 pubsta->addr, tid);
635
636 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
637 sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
638 sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
639 sdata->vif.type != NL80211_IFTYPE_AP &&
640 sdata->vif.type != NL80211_IFTYPE_ADHOC)
641 return -EINVAL;
642
643 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
644 ht_dbg(sdata,
645 "BA sessions blocked - Denying BA session request %pM tid %d\n",
646 sta->sta.addr, tid);
647 return -EINVAL;
648 }
649
650 if (test_sta_flag(sta, WLAN_STA_MFP) &&
651 !test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
652 ht_dbg(sdata,
653 "MFP STA not authorized - deny BA session request %pM tid %d\n",
654 sta->sta.addr, tid);
655 return -EINVAL;
656 }
657
658 /*
659 * 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a
660 * member of an IBSS, and has no other existing Block Ack agreement
661 * with the recipient STA, then the initiating STA shall transmit a
662 * Probe Request frame to the recipient STA and shall not transmit an
663 * ADDBA Request frame unless it receives a Probe Response frame
664 * from the recipient within dot11ADDBAFailureTimeout.
665 *
666 * The probe request mechanism for ADDBA is currently not implemented,
667 * but we only build up Block Ack session with HT STAs. This information
668 * is set when we receive a bss info from a probe response or a beacon.
669 */
670 if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC &&
671 !sta->sta.deflink.ht_cap.ht_supported) {
672 ht_dbg(sdata,
673 "BA request denied - IBSS STA %pM does not advertise HT support\n",
674 pubsta->addr);
675 return -EINVAL;
676 }
677
678 spin_lock_bh(&sta->lock);
679
680 /* we have tried too many times, receiver does not want A-MPDU */
681 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
682 ret = -EBUSY;
683 goto err_unlock_sta;
684 }
685
686 /*
687 * if we have tried more than HT_AGG_BURST_RETRIES times we
688 * will spread our requests in time to avoid stalling connection
689 * for too long
690 */
691 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES &&
692 time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] +
693 HT_AGG_RETRIES_PERIOD)) {
694 ht_dbg(sdata,
695 "BA request denied - %d failed requests on %pM tid %u\n",
696 sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid);
697 ret = -EBUSY;
698 goto err_unlock_sta;
699 }
700
701 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
702 /* check if the TID is not in aggregation flow already */
703 if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) {
704 ht_dbg(sdata,
705 "BA request denied - session is not idle on %pM tid %u\n",
706 sta->sta.addr, tid);
707 ret = -EAGAIN;
708 goto err_unlock_sta;
709 }
710
711 /* prepare A-MPDU MLME for Tx aggregation */
712 tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
713 if (!tid_tx) {
714 ret = -ENOMEM;
715 goto err_unlock_sta;
716 }
717
718 skb_queue_head_init(&tid_tx->pending);
719 __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
720
721 tid_tx->timeout = timeout;
722 tid_tx->sta = sta;
723 tid_tx->tid = tid;
724
725 /* response timer */
726 timer_setup(&tid_tx->addba_resp_timer, sta_addba_resp_timer_expired, 0);
727
728 /* tx timer */
729 timer_setup(&tid_tx->session_timer,
730 sta_tx_agg_session_timer_expired, TIMER_DEFERRABLE);
731
732 /* assign a dialog token */
733 sta->ampdu_mlme.dialog_token_allocator++;
734 tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
735
736 /*
737 * Finally, assign it to the start array; the work item will
738 * collect it and move it to the normal array.
739 */
740 sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
741
742 wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
743
744 /* this flow continues off the work */
745 err_unlock_sta:
746 spin_unlock_bh(&sta->lock);
747 return ret;
748}
749EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
750
751static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
752 struct sta_info *sta, u16 tid)
753{
754 struct tid_ampdu_tx *tid_tx;
755 struct ieee80211_ampdu_params params = {
756 .sta = &sta->sta,
757 .action = IEEE80211_AMPDU_TX_OPERATIONAL,
758 .tid = tid,
759 .timeout = 0,
760 .ssn = 0,
761 };
762
763 lockdep_assert_wiphy(sta->local->hw.wiphy);
764
765 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
766 params.buf_size = tid_tx->buf_size;
767 params.amsdu = tid_tx->amsdu;
768
769 ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n",
770 sta->sta.addr, tid);
771
772 drv_ampdu_action(local, sta->sdata, ¶ms);
773
774 /*
775 * synchronize with TX path, while splicing the TX path
776 * should block so it won't put more packets onto pending.
777 */
778 spin_lock_bh(&sta->lock);
779
780 ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
781 /*
782 * Now mark as operational. This will be visible
783 * in the TX path, and lets it go lock-free in
784 * the common case.
785 */
786 set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
787 ieee80211_agg_splice_finish(sta->sdata, tid);
788
789 spin_unlock_bh(&sta->lock);
790
791 ieee80211_agg_start_txq(sta, tid, true);
792}
793
794void ieee80211_start_tx_ba_cb(struct sta_info *sta, int tid,
795 struct tid_ampdu_tx *tid_tx)
796{
797 struct ieee80211_sub_if_data *sdata = sta->sdata;
798 struct ieee80211_local *local = sdata->local;
799
800 lockdep_assert_wiphy(sta->local->hw.wiphy);
801
802 if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
803 return;
804
805 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state) ||
806 test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state))
807 return;
808
809 if (!test_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state)) {
810 ieee80211_send_addba_with_timeout(sta, tid_tx);
811 /* RESPONSE_RECEIVED state whould trigger the flow again */
812 return;
813 }
814
815 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
816 ieee80211_agg_tx_operational(local, sta, tid);
817}
818
819static struct tid_ampdu_tx *
820ieee80211_lookup_tid_tx(struct ieee80211_sub_if_data *sdata,
821 const u8 *ra, u16 tid, struct sta_info **sta)
822{
823 struct tid_ampdu_tx *tid_tx;
824
825 if (tid >= IEEE80211_NUM_TIDS) {
826 ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n",
827 tid, IEEE80211_NUM_TIDS);
828 return NULL;
829 }
830
831 *sta = sta_info_get_bss(sdata, ra);
832 if (!*sta) {
833 ht_dbg(sdata, "Could not find station: %pM\n", ra);
834 return NULL;
835 }
836
837 tid_tx = rcu_dereference((*sta)->ampdu_mlme.tid_tx[tid]);
838
839 if (WARN_ON(!tid_tx))
840 ht_dbg(sdata, "addBA was not requested!\n");
841
842 return tid_tx;
843}
844
845void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
846 const u8 *ra, u16 tid)
847{
848 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
849 struct ieee80211_local *local = sdata->local;
850 struct sta_info *sta;
851 struct tid_ampdu_tx *tid_tx;
852
853 trace_api_start_tx_ba_cb(sdata, ra, tid);
854
855 rcu_read_lock();
856 tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
857 if (!tid_tx)
858 goto out;
859
860 set_bit(HT_AGG_STATE_START_CB, &tid_tx->state);
861 wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
862 out:
863 rcu_read_unlock();
864}
865EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
866
867int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
868{
869 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
870 struct ieee80211_sub_if_data *sdata = sta->sdata;
871 struct ieee80211_local *local = sdata->local;
872 struct tid_ampdu_tx *tid_tx;
873 int ret = 0;
874
875 trace_api_stop_tx_ba_session(pubsta, tid);
876
877 if (!local->ops->ampdu_action)
878 return -EINVAL;
879
880 if (tid >= IEEE80211_NUM_TIDS)
881 return -EINVAL;
882
883 spin_lock_bh(&sta->lock);
884 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
885
886 if (!tid_tx) {
887 ret = -ENOENT;
888 goto unlock;
889 }
890
891 WARN(sta->reserved_tid == tid,
892 "Requested to stop BA session on reserved tid=%d", tid);
893
894 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
895 /* already in progress stopping it */
896 ret = 0;
897 goto unlock;
898 }
899
900 set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
901 wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
902
903 unlock:
904 spin_unlock_bh(&sta->lock);
905 return ret;
906}
907EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
908
909void ieee80211_stop_tx_ba_cb(struct sta_info *sta, int tid,
910 struct tid_ampdu_tx *tid_tx)
911{
912 struct ieee80211_sub_if_data *sdata = sta->sdata;
913 bool send_delba = false;
914 bool start_txq = false;
915
916 ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n",
917 sta->sta.addr, tid);
918
919 spin_lock_bh(&sta->lock);
920
921 if (!test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
922 ht_dbg(sdata,
923 "unexpected callback to A-MPDU stop for %pM tid %d\n",
924 sta->sta.addr, tid);
925 goto unlock_sta;
926 }
927
928 if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
929 send_delba = true;
930
931 ieee80211_remove_tid_tx(sta, tid);
932 start_txq = true;
933
934 unlock_sta:
935 spin_unlock_bh(&sta->lock);
936
937 if (start_txq)
938 ieee80211_agg_start_txq(sta, tid, false);
939
940 if (send_delba)
941 ieee80211_send_delba(sdata, sta->sta.addr, tid,
942 WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
943}
944
945void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
946 const u8 *ra, u16 tid)
947{
948 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
949 struct ieee80211_local *local = sdata->local;
950 struct sta_info *sta;
951 struct tid_ampdu_tx *tid_tx;
952
953 trace_api_stop_tx_ba_cb(sdata, ra, tid);
954
955 rcu_read_lock();
956 tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
957 if (!tid_tx)
958 goto out;
959
960 set_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state);
961 wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
962 out:
963 rcu_read_unlock();
964}
965EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
966
967
968void ieee80211_process_addba_resp(struct ieee80211_local *local,
969 struct sta_info *sta,
970 struct ieee80211_mgmt *mgmt,
971 size_t len)
972{
973 struct tid_ampdu_tx *tid_tx;
974 struct ieee80211_txq *txq;
975 u16 capab, tid, buf_size;
976 bool amsdu;
977
978 lockdep_assert_wiphy(sta->local->hw.wiphy);
979
980 capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
981 amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK;
982 tid = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_TID_MASK);
983 buf_size = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
984 buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes);
985
986 txq = sta->sta.txq[tid];
987 if (!amsdu && txq)
988 set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags);
989
990 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
991 if (!tid_tx)
992 return;
993
994 if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
995 ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n",
996 sta->sta.addr, tid);
997 return;
998 }
999
1000 del_timer_sync(&tid_tx->addba_resp_timer);
1001
1002 ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n",
1003 sta->sta.addr, tid);
1004
1005 /*
1006 * addba_resp_timer may have fired before we got here, and
1007 * caused WANT_STOP to be set. If the stop then was already
1008 * processed further, STOPPING might be set.
1009 */
1010 if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) ||
1011 test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
1012 ht_dbg(sta->sdata,
1013 "got addBA resp for %pM tid %d but we already gave up\n",
1014 sta->sta.addr, tid);
1015 return;
1016 }
1017
1018 /*
1019 * IEEE 802.11-2007 7.3.1.14:
1020 * In an ADDBA Response frame, when the Status Code field
1021 * is set to 0, the Buffer Size subfield is set to a value
1022 * of at least 1.
1023 */
1024 if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
1025 == WLAN_STATUS_SUCCESS && buf_size) {
1026 if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
1027 &tid_tx->state)) {
1028 /* ignore duplicate response */
1029 return;
1030 }
1031
1032 tid_tx->buf_size = buf_size;
1033 tid_tx->amsdu = amsdu;
1034
1035 if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
1036 ieee80211_agg_tx_operational(local, sta, tid);
1037
1038 sta->ampdu_mlme.addba_req_num[tid] = 0;
1039
1040 tid_tx->timeout =
1041 le16_to_cpu(mgmt->u.action.u.addba_resp.timeout);
1042
1043 if (tid_tx->timeout) {
1044 mod_timer(&tid_tx->session_timer,
1045 TU_TO_EXP_TIME(tid_tx->timeout));
1046 tid_tx->last_tx = jiffies;
1047 }
1048
1049 } else {
1050 __ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED);
1051 }
1052}