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 - 2024 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
ieee80211_send_addba_request(struct sta_info * sta,u16 tid,u8 dialog_token,u16 start_seq_num,u16 agg_size,u16 timeout)61 static void ieee80211_send_addba_request(struct sta_info *sta, u16 tid,
62 u8 dialog_token, u16 start_seq_num,
63 u16 agg_size, u16 timeout)
64 {
65 struct ieee80211_sub_if_data *sdata = sta->sdata;
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) +
72 2 + sizeof(struct ieee80211_addba_ext_ie) +
73 local->hw.extra_tx_headroom);
74 if (!skb)
75 return;
76
77 skb_reserve(skb, local->hw.extra_tx_headroom);
78 mgmt = ieee80211_mgmt_ba(skb, sta->sta.addr, sdata);
79
80 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
81
82 mgmt->u.action.category = WLAN_CATEGORY_BACK;
83 mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
84
85 mgmt->u.action.u.addba_req.dialog_token = dialog_token;
86 capab = IEEE80211_ADDBA_PARAM_AMSDU_MASK;
87 capab |= IEEE80211_ADDBA_PARAM_POLICY_MASK;
88 capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
89 capab |= u16_encode_bits(agg_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
90
91 mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
92
93 mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
94 mgmt->u.action.u.addba_req.start_seq_num =
95 cpu_to_le16(start_seq_num << 4);
96
97 if (sta->sta.deflink.he_cap.has_he)
98 ieee80211_add_addbaext(skb, 0, agg_size);
99
100 ieee80211_tx_skb_tid(sdata, skb, tid, -1);
101 }
102
ieee80211_send_bar(struct ieee80211_vif * vif,u8 * ra,u16 tid,u16 ssn)103 void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn)
104 {
105 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
106 struct ieee80211_local *local = sdata->local;
107 struct sk_buff *skb;
108 struct ieee80211_bar *bar;
109 u16 bar_control = 0;
110
111 skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
112 if (!skb)
113 return;
114
115 skb_reserve(skb, local->hw.extra_tx_headroom);
116 bar = skb_put_zero(skb, sizeof(*bar));
117 bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
118 IEEE80211_STYPE_BACK_REQ);
119 memcpy(bar->ra, ra, ETH_ALEN);
120 memcpy(bar->ta, sdata->vif.addr, ETH_ALEN);
121 bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
122 bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
123 bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT);
124 bar->control = cpu_to_le16(bar_control);
125 bar->start_seq_num = cpu_to_le16(ssn);
126
127 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
128 IEEE80211_TX_CTL_REQ_TX_STATUS;
129 ieee80211_tx_skb_tid(sdata, skb, tid, -1);
130 }
131 EXPORT_SYMBOL(ieee80211_send_bar);
132
ieee80211_assign_tid_tx(struct sta_info * sta,int tid,struct tid_ampdu_tx * tid_tx)133 void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
134 struct tid_ampdu_tx *tid_tx)
135 {
136 lockdep_assert_wiphy(sta->local->hw.wiphy);
137 lockdep_assert_held(&sta->lock);
138 rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
139 }
140
141 /*
142 * When multiple aggregation sessions on multiple stations
143 * are being created/destroyed simultaneously, we need to
144 * refcount the global queue stop caused by that in order
145 * to not get into a situation where one of the aggregation
146 * setup or teardown re-enables queues before the other is
147 * ready to handle that.
148 *
149 * These two functions take care of this issue by keeping
150 * a global "agg_queue_stop" refcount.
151 */
__acquires(agg_queue)152 static void __acquires(agg_queue)
153 ieee80211_stop_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
154 {
155 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
156
157 /* we do refcounting here, so don't use the queue reason refcounting */
158
159 if (atomic_inc_return(&sdata->local->agg_queue_stop[queue]) == 1)
160 ieee80211_stop_queue_by_reason(
161 &sdata->local->hw, queue,
162 IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
163 false);
164 __acquire(agg_queue);
165 }
166
__releases(agg_queue)167 static void __releases(agg_queue)
168 ieee80211_wake_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
169 {
170 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
171
172 if (atomic_dec_return(&sdata->local->agg_queue_stop[queue]) == 0)
173 ieee80211_wake_queue_by_reason(
174 &sdata->local->hw, queue,
175 IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
176 false);
177 __release(agg_queue);
178 }
179
180 static void
ieee80211_agg_stop_txq(struct sta_info * sta,int tid)181 ieee80211_agg_stop_txq(struct sta_info *sta, int tid)
182 {
183 struct ieee80211_txq *txq = sta->sta.txq[tid];
184 struct ieee80211_sub_if_data *sdata;
185 struct fq *fq;
186 struct txq_info *txqi;
187
188 if (!txq)
189 return;
190
191 txqi = to_txq_info(txq);
192 sdata = vif_to_sdata(txq->vif);
193 fq = &sdata->local->fq;
194
195 /* Lock here to protect against further seqno updates on dequeue */
196 spin_lock_bh(&fq->lock);
197 set_bit(IEEE80211_TXQ_STOP, &txqi->flags);
198 spin_unlock_bh(&fq->lock);
199 }
200
201 static void
ieee80211_agg_start_txq(struct sta_info * sta,int tid,bool enable)202 ieee80211_agg_start_txq(struct sta_info *sta, int tid, bool enable)
203 {
204 struct ieee80211_txq *txq = sta->sta.txq[tid];
205 struct txq_info *txqi;
206
207 lockdep_assert_wiphy(sta->local->hw.wiphy);
208
209 if (!txq)
210 return;
211
212 txqi = to_txq_info(txq);
213
214 if (enable)
215 set_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
216 else
217 clear_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
218
219 clear_bit(IEEE80211_TXQ_STOP, &txqi->flags);
220 local_bh_disable();
221 rcu_read_lock();
222 schedule_and_wake_txq(sta->sdata->local, txqi);
223 rcu_read_unlock();
224 local_bh_enable();
225 }
226
227 /*
228 * splice packets from the STA's pending to the local pending,
229 * requires a call to ieee80211_agg_splice_finish later
230 */
__acquires(agg_queue)231 static void __acquires(agg_queue)
232 ieee80211_agg_splice_packets(struct ieee80211_sub_if_data *sdata,
233 struct tid_ampdu_tx *tid_tx, u16 tid)
234 {
235 struct ieee80211_local *local = sdata->local;
236 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
237 unsigned long flags;
238
239 ieee80211_stop_queue_agg(sdata, tid);
240
241 if (WARN(!tid_tx,
242 "TID %d gone but expected when splicing aggregates from the pending queue\n",
243 tid))
244 return;
245
246 if (!skb_queue_empty(&tid_tx->pending)) {
247 spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
248 /* copy over remaining packets */
249 skb_queue_splice_tail_init(&tid_tx->pending,
250 &local->pending[queue]);
251 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
252 }
253 }
254
__releases(agg_queue)255 static void __releases(agg_queue)
256 ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid)
257 {
258 ieee80211_wake_queue_agg(sdata, tid);
259 }
260
ieee80211_remove_tid_tx(struct sta_info * sta,int tid)261 static void ieee80211_remove_tid_tx(struct sta_info *sta, int tid)
262 {
263 struct tid_ampdu_tx *tid_tx;
264
265 lockdep_assert_wiphy(sta->local->hw.wiphy);
266 lockdep_assert_held(&sta->lock);
267
268 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
269
270 /*
271 * When we get here, the TX path will not be lockless any more wrt.
272 * aggregation, since the OPERATIONAL bit has long been cleared.
273 * Thus it will block on getting the lock, if it occurs. So if we
274 * stop the queue now, we will not get any more packets, and any
275 * that might be being processed will wait for us here, thereby
276 * guaranteeing that no packets go to the tid_tx pending queue any
277 * more.
278 */
279
280 ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
281
282 /* future packets must not find the tid_tx struct any more */
283 ieee80211_assign_tid_tx(sta, tid, NULL);
284
285 ieee80211_agg_splice_finish(sta->sdata, tid);
286
287 kfree_rcu(tid_tx, rcu_head);
288 }
289
__ieee80211_stop_tx_ba_session(struct sta_info * sta,u16 tid,enum ieee80211_agg_stop_reason reason)290 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
291 enum ieee80211_agg_stop_reason reason)
292 {
293 struct ieee80211_local *local = sta->local;
294 struct tid_ampdu_tx *tid_tx;
295 struct ieee80211_ampdu_params params = {
296 .sta = &sta->sta,
297 .tid = tid,
298 .buf_size = 0,
299 .amsdu = false,
300 .timeout = 0,
301 .ssn = 0,
302 };
303 int ret;
304
305 lockdep_assert_wiphy(sta->local->hw.wiphy);
306
307 switch (reason) {
308 case AGG_STOP_DECLINED:
309 case AGG_STOP_LOCAL_REQUEST:
310 case AGG_STOP_PEER_REQUEST:
311 params.action = IEEE80211_AMPDU_TX_STOP_CONT;
312 break;
313 case AGG_STOP_DESTROY_STA:
314 params.action = IEEE80211_AMPDU_TX_STOP_FLUSH;
315 break;
316 default:
317 WARN_ON_ONCE(1);
318 return -EINVAL;
319 }
320
321 spin_lock_bh(&sta->lock);
322
323 /* free struct pending for start, if present */
324 tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
325 kfree(tid_tx);
326 sta->ampdu_mlme.tid_start_tx[tid] = NULL;
327
328 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
329 if (!tid_tx) {
330 spin_unlock_bh(&sta->lock);
331 return -ENOENT;
332 }
333
334 /*
335 * if we're already stopping ignore any new requests to stop
336 * unless we're destroying it in which case notify the driver
337 */
338 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
339 spin_unlock_bh(&sta->lock);
340 if (reason != AGG_STOP_DESTROY_STA)
341 return -EALREADY;
342 params.action = IEEE80211_AMPDU_TX_STOP_FLUSH_CONT;
343 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
344 WARN_ON_ONCE(ret);
345 return 0;
346 }
347
348 if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
349 /* not even started yet! */
350 ieee80211_assign_tid_tx(sta, tid, NULL);
351 spin_unlock_bh(&sta->lock);
352 kfree_rcu(tid_tx, rcu_head);
353 return 0;
354 }
355
356 set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
357
358 ieee80211_agg_stop_txq(sta, tid);
359
360 spin_unlock_bh(&sta->lock);
361
362 ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n",
363 sta->sta.addr, tid);
364
365 timer_delete_sync(&tid_tx->addba_resp_timer);
366 timer_delete_sync(&tid_tx->session_timer);
367
368 /*
369 * After this packets are no longer handed right through
370 * to the driver but are put onto tid_tx->pending instead,
371 * with locking to ensure proper access.
372 */
373 clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
374
375 /*
376 * There might be a few packets being processed right now (on
377 * another CPU) that have already gotten past the aggregation
378 * check when it was still OPERATIONAL and consequently have
379 * IEEE80211_TX_CTL_AMPDU set. In that case, this code might
380 * call into the driver at the same time or even before the
381 * TX paths calls into it, which could confuse the driver.
382 *
383 * Wait for all currently running TX paths to finish before
384 * telling the driver. New packets will not go through since
385 * the aggregation session is no longer OPERATIONAL.
386 */
387 if (!local->in_reconfig)
388 synchronize_net();
389
390 tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ?
391 WLAN_BACK_RECIPIENT :
392 WLAN_BACK_INITIATOR;
393 tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST;
394
395 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
396
397 /* HW shall not deny going back to legacy */
398 if (WARN_ON(ret)) {
399 /*
400 * We may have pending packets get stuck in this case...
401 * Not bothering with a workaround for now.
402 */
403 }
404
405 /*
406 * In the case of AGG_STOP_DESTROY_STA, the driver won't
407 * necessarily call ieee80211_stop_tx_ba_cb(), so this may
408 * seem like we can leave the tid_tx data pending forever.
409 * This is true, in a way, but "forever" is only until the
410 * station struct is actually destroyed. In the meantime,
411 * leaving it around ensures that we don't transmit packets
412 * to the driver on this TID which might confuse it.
413 */
414
415 return 0;
416 }
417
418 /*
419 * After sending add Block Ack request we activated a timer until
420 * add Block Ack response will arrive from the recipient.
421 * If this timer expires sta_addba_resp_timer_expired will be executed.
422 */
sta_addba_resp_timer_expired(struct timer_list * t)423 static void sta_addba_resp_timer_expired(struct timer_list *t)
424 {
425 struct tid_ampdu_tx *tid_tx = timer_container_of(tid_tx, t,
426 addba_resp_timer);
427 struct sta_info *sta = tid_tx->sta;
428 u8 tid = tid_tx->tid;
429
430 /* check if the TID waits for addBA response */
431 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
432 ht_dbg(sta->sdata,
433 "timer expired on %pM tid %d not expecting addBA response\n",
434 sta->sta.addr, tid);
435 return;
436 }
437
438 ht_dbg(sta->sdata, "addBA response timer expired on %pM tid %d\n",
439 sta->sta.addr, tid);
440
441 ieee80211_stop_tx_ba_session(&sta->sta, tid);
442 }
443
ieee80211_send_addba_with_timeout(struct sta_info * sta,struct tid_ampdu_tx * tid_tx)444 static void ieee80211_send_addba_with_timeout(struct sta_info *sta,
445 struct tid_ampdu_tx *tid_tx)
446 {
447 struct ieee80211_sub_if_data *sdata = sta->sdata;
448 struct ieee80211_local *local = sta->local;
449 u8 tid = tid_tx->tid;
450 u16 buf_size;
451
452 if (WARN_ON_ONCE(test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state) ||
453 test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state)))
454 return;
455
456 lockdep_assert_wiphy(sta->local->hw.wiphy);
457
458 /* activate the timer for the recipient's addBA response */
459 mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
460 ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n",
461 sta->sta.addr, tid);
462
463 spin_lock_bh(&sta->lock);
464 sta->ampdu_mlme.last_addba_req_time[tid] = jiffies;
465 sta->ampdu_mlme.addba_req_num[tid]++;
466 spin_unlock_bh(&sta->lock);
467
468 if (sta->sta.valid_links ||
469 sta->sta.deflink.eht_cap.has_eht ||
470 ieee80211_hw_check(&local->hw, STRICT)) {
471 buf_size = local->hw.max_tx_aggregation_subframes;
472 } else if (sta->sta.deflink.he_cap.has_he) {
473 buf_size = min_t(u16, local->hw.max_tx_aggregation_subframes,
474 IEEE80211_MAX_AMPDU_BUF_HE);
475 } else {
476 /*
477 * We really should use what the driver told us it will
478 * transmit as the maximum, but certain APs (e.g. the
479 * LinkSys WRT120N with FW v1.0.07 build 002 Jun 18 2012)
480 * will crash when we use a lower number.
481 */
482 buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
483 }
484
485 /* send AddBA request */
486 ieee80211_send_addba_request(sta, tid, tid_tx->dialog_token,
487 tid_tx->ssn, buf_size, tid_tx->timeout);
488
489 WARN_ON(test_and_set_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state));
490 }
491
ieee80211_tx_ba_session_handle_start(struct sta_info * sta,int tid)492 void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
493 {
494 struct tid_ampdu_tx *tid_tx;
495 struct ieee80211_local *local = sta->local;
496 struct ieee80211_sub_if_data *sdata = sta->sdata;
497 struct ieee80211_ampdu_params params = {
498 .sta = &sta->sta,
499 .action = IEEE80211_AMPDU_TX_START,
500 .tid = tid,
501 .buf_size = 0,
502 .amsdu = false,
503 .timeout = 0,
504 };
505 int ret;
506
507 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
508
509 /*
510 * Start queuing up packets for this aggregation session.
511 * We're going to release them once the driver is OK with
512 * that.
513 */
514 clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
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 tid_tx->ssn = params.ssn;
527 if (ret == IEEE80211_AMPDU_TX_START_DELAY_ADDBA) {
528 return;
529 } else if (ret == IEEE80211_AMPDU_TX_START_IMMEDIATE) {
530 /*
531 * We didn't send the request yet, so don't need to check
532 * here if we already got a response, just mark as driver
533 * ready immediately.
534 */
535 set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state);
536 } else if (ret) {
537 ht_dbg(sdata,
538 "BA request denied - HW unavailable for %pM tid %d\n",
539 sta->sta.addr, tid);
540 spin_lock_bh(&sta->lock);
541 ieee80211_agg_splice_packets(sdata, tid_tx, tid);
542 ieee80211_assign_tid_tx(sta, tid, NULL);
543 ieee80211_agg_splice_finish(sdata, tid);
544 spin_unlock_bh(&sta->lock);
545
546 ieee80211_agg_start_txq(sta, tid, false);
547
548 kfree_rcu(tid_tx, rcu_head);
549 return;
550 }
551
552 ieee80211_send_addba_with_timeout(sta, tid_tx);
553 }
554
ieee80211_refresh_tx_agg_session_timer(struct ieee80211_sta * pubsta,u16 tid)555 void ieee80211_refresh_tx_agg_session_timer(struct ieee80211_sta *pubsta,
556 u16 tid)
557 {
558 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
559 struct tid_ampdu_tx *tid_tx;
560
561 if (WARN_ON_ONCE(tid >= IEEE80211_NUM_TIDS))
562 return;
563
564 tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
565 if (!tid_tx)
566 return;
567
568 tid_tx->last_tx = jiffies;
569 }
570 EXPORT_SYMBOL(ieee80211_refresh_tx_agg_session_timer);
571
572 /*
573 * After accepting the AddBA Response we activated a timer,
574 * resetting it after each frame that we send.
575 */
sta_tx_agg_session_timer_expired(struct timer_list * t)576 static void sta_tx_agg_session_timer_expired(struct timer_list *t)
577 {
578 struct tid_ampdu_tx *tid_tx = timer_container_of(tid_tx, t,
579 session_timer);
580 struct sta_info *sta = tid_tx->sta;
581 u8 tid = tid_tx->tid;
582 unsigned long timeout;
583
584 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
585 return;
586 }
587
588 timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout);
589 if (time_is_after_jiffies(timeout)) {
590 mod_timer(&tid_tx->session_timer, timeout);
591 return;
592 }
593
594 ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n",
595 sta->sta.addr, tid);
596
597 ieee80211_stop_tx_ba_session(&sta->sta, tid);
598 }
599
ieee80211_start_tx_ba_session(struct ieee80211_sta * pubsta,u16 tid,u16 timeout)600 int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
601 u16 timeout)
602 {
603 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
604 struct ieee80211_sub_if_data *sdata = sta->sdata;
605 struct ieee80211_local *local = sdata->local;
606 struct tid_ampdu_tx *tid_tx;
607 int ret = 0;
608
609 trace_api_start_tx_ba_session(pubsta, tid);
610
611 if (WARN(sta->reserved_tid == tid,
612 "Requested to start BA session on reserved tid=%d", tid))
613 return -EINVAL;
614
615 if (!pubsta->valid_links &&
616 !pubsta->deflink.ht_cap.ht_supported &&
617 !pubsta->deflink.vht_cap.vht_supported &&
618 !pubsta->deflink.he_cap.has_he &&
619 !pubsta->deflink.eht_cap.has_eht &&
620 !pubsta->deflink.s1g_cap.s1g)
621 return -EINVAL;
622
623 if (WARN_ON_ONCE(!local->ops->ampdu_action))
624 return -EINVAL;
625
626 if ((tid >= IEEE80211_NUM_TIDS) ||
627 !ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) ||
628 ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW))
629 return -EINVAL;
630
631 if (WARN_ON(tid >= IEEE80211_FIRST_TSPEC_TSID))
632 return -EINVAL;
633
634 ht_dbg(sdata, "Open BA session requested for %pM tid %u\n",
635 pubsta->addr, tid);
636
637 if (sdata->vif.type != NL80211_IFTYPE_STATION &&
638 sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
639 sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
640 sdata->vif.type != NL80211_IFTYPE_AP &&
641 sdata->vif.type != NL80211_IFTYPE_ADHOC)
642 return -EINVAL;
643
644 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
645 ht_dbg(sdata,
646 "BA sessions blocked - Denying BA session request %pM tid %d\n",
647 sta->sta.addr, tid);
648 return -EINVAL;
649 }
650
651 if (test_sta_flag(sta, WLAN_STA_MFP) &&
652 !test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
653 ht_dbg(sdata,
654 "MFP STA not authorized - deny BA session request %pM tid %d\n",
655 sta->sta.addr, tid);
656 return -EINVAL;
657 }
658
659 /*
660 * 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a
661 * member of an IBSS, and has no other existing Block Ack agreement
662 * with the recipient STA, then the initiating STA shall transmit a
663 * Probe Request frame to the recipient STA and shall not transmit an
664 * ADDBA Request frame unless it receives a Probe Response frame
665 * from the recipient within dot11ADDBAFailureTimeout.
666 *
667 * The probe request mechanism for ADDBA is currently not implemented,
668 * but we only build up Block Ack session with HT STAs. This information
669 * is set when we receive a bss info from a probe response or a beacon.
670 */
671 if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC &&
672 !sta->sta.deflink.ht_cap.ht_supported) {
673 ht_dbg(sdata,
674 "BA request denied - IBSS STA %pM does not advertise HT support\n",
675 pubsta->addr);
676 return -EINVAL;
677 }
678
679 spin_lock_bh(&sta->lock);
680
681 /* we have tried too many times, receiver does not want A-MPDU */
682 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
683 ret = -EBUSY;
684 goto err_unlock_sta;
685 }
686
687 /*
688 * if we have tried more than HT_AGG_BURST_RETRIES times we
689 * will spread our requests in time to avoid stalling connection
690 * for too long
691 */
692 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES &&
693 time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] +
694 HT_AGG_RETRIES_PERIOD)) {
695 ht_dbg(sdata,
696 "BA request denied - %d failed requests on %pM tid %u\n",
697 sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid);
698 ret = -EBUSY;
699 goto err_unlock_sta;
700 }
701
702 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
703 /* check if the TID is not in aggregation flow already */
704 if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) {
705 ht_dbg(sdata,
706 "BA request denied - session is not idle on %pM tid %u\n",
707 sta->sta.addr, tid);
708 ret = -EAGAIN;
709 goto err_unlock_sta;
710 }
711
712 /* prepare A-MPDU MLME for Tx aggregation */
713 tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
714 if (!tid_tx) {
715 ret = -ENOMEM;
716 goto err_unlock_sta;
717 }
718
719 skb_queue_head_init(&tid_tx->pending);
720 __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
721
722 tid_tx->timeout = timeout;
723 tid_tx->sta = sta;
724 tid_tx->tid = tid;
725
726 /* response timer */
727 timer_setup(&tid_tx->addba_resp_timer, sta_addba_resp_timer_expired, 0);
728
729 /* tx timer */
730 timer_setup(&tid_tx->session_timer,
731 sta_tx_agg_session_timer_expired, TIMER_DEFERRABLE);
732
733 /* assign a dialog token */
734 sta->ampdu_mlme.dialog_token_allocator++;
735 tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
736
737 /*
738 * Finally, assign it to the start array; the work item will
739 * collect it and move it to the normal array.
740 */
741 sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
742
743 wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
744
745 /* this flow continues off the work */
746 err_unlock_sta:
747 spin_unlock_bh(&sta->lock);
748 return ret;
749 }
750 EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
751
ieee80211_agg_tx_operational(struct ieee80211_local * local,struct sta_info * sta,u16 tid)752 static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
753 struct sta_info *sta, u16 tid)
754 {
755 struct tid_ampdu_tx *tid_tx;
756 struct ieee80211_ampdu_params params = {
757 .sta = &sta->sta,
758 .action = IEEE80211_AMPDU_TX_OPERATIONAL,
759 .tid = tid,
760 .timeout = 0,
761 .ssn = 0,
762 };
763
764 lockdep_assert_wiphy(sta->local->hw.wiphy);
765
766 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
767 params.buf_size = tid_tx->buf_size;
768 params.amsdu = tid_tx->amsdu;
769
770 ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n",
771 sta->sta.addr, tid);
772
773 drv_ampdu_action(local, sta->sdata, ¶ms);
774
775 /*
776 * synchronize with TX path, while splicing the TX path
777 * should block so it won't put more packets onto pending.
778 */
779 spin_lock_bh(&sta->lock);
780
781 ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
782 /*
783 * Now mark as operational. This will be visible
784 * in the TX path, and lets it go lock-free in
785 * the common case.
786 */
787 set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
788 ieee80211_agg_splice_finish(sta->sdata, tid);
789
790 spin_unlock_bh(&sta->lock);
791
792 ieee80211_agg_start_txq(sta, tid, true);
793 }
794
ieee80211_start_tx_ba_cb(struct sta_info * sta,int tid,struct tid_ampdu_tx * tid_tx)795 void ieee80211_start_tx_ba_cb(struct sta_info *sta, int tid,
796 struct tid_ampdu_tx *tid_tx)
797 {
798 struct ieee80211_sub_if_data *sdata = sta->sdata;
799 struct ieee80211_local *local = sdata->local;
800
801 lockdep_assert_wiphy(sta->local->hw.wiphy);
802
803 if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
804 return;
805
806 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state) ||
807 test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state))
808 return;
809
810 if (!test_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state)) {
811 ieee80211_send_addba_with_timeout(sta, tid_tx);
812 /* RESPONSE_RECEIVED state would trigger the flow again */
813 return;
814 }
815
816 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
817 ieee80211_agg_tx_operational(local, sta, tid);
818 }
819
820 static struct tid_ampdu_tx *
ieee80211_lookup_tid_tx(struct ieee80211_sub_if_data * sdata,const u8 * ra,u16 tid,struct sta_info ** sta)821 ieee80211_lookup_tid_tx(struct ieee80211_sub_if_data *sdata,
822 const u8 *ra, u16 tid, struct sta_info **sta)
823 {
824 struct tid_ampdu_tx *tid_tx;
825
826 if (tid >= IEEE80211_NUM_TIDS) {
827 ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n",
828 tid, IEEE80211_NUM_TIDS);
829 return NULL;
830 }
831
832 *sta = sta_info_get_bss(sdata, ra);
833 if (!*sta) {
834 ht_dbg(sdata, "Could not find station: %pM\n", ra);
835 return NULL;
836 }
837
838 tid_tx = rcu_dereference((*sta)->ampdu_mlme.tid_tx[tid]);
839
840 if (WARN_ON(!tid_tx))
841 ht_dbg(sdata, "addBA was not requested!\n");
842
843 return tid_tx;
844 }
845
ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif * vif,const u8 * ra,u16 tid)846 void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
847 const u8 *ra, u16 tid)
848 {
849 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
850 struct ieee80211_local *local = sdata->local;
851 struct sta_info *sta;
852 struct tid_ampdu_tx *tid_tx;
853
854 trace_api_start_tx_ba_cb(sdata, ra, tid);
855
856 rcu_read_lock();
857 tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
858 if (!tid_tx)
859 goto out;
860
861 set_bit(HT_AGG_STATE_START_CB, &tid_tx->state);
862 wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
863 out:
864 rcu_read_unlock();
865 }
866 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
867
ieee80211_stop_tx_ba_session(struct ieee80211_sta * pubsta,u16 tid)868 int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
869 {
870 struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
871 struct ieee80211_sub_if_data *sdata = sta->sdata;
872 struct ieee80211_local *local = sdata->local;
873 struct tid_ampdu_tx *tid_tx;
874 int ret = 0;
875
876 trace_api_stop_tx_ba_session(pubsta, tid);
877
878 if (!local->ops->ampdu_action)
879 return -EINVAL;
880
881 if (tid >= IEEE80211_NUM_TIDS)
882 return -EINVAL;
883
884 spin_lock_bh(&sta->lock);
885 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
886
887 if (!tid_tx) {
888 ret = -ENOENT;
889 goto unlock;
890 }
891
892 WARN(sta->reserved_tid == tid,
893 "Requested to stop BA session on reserved tid=%d", tid);
894
895 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
896 /* already in progress stopping it */
897 ret = 0;
898 goto unlock;
899 }
900
901 set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
902 wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
903
904 unlock:
905 spin_unlock_bh(&sta->lock);
906 return ret;
907 }
908 EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
909
ieee80211_stop_tx_ba_cb(struct sta_info * sta,int tid,struct tid_ampdu_tx * tid_tx)910 void ieee80211_stop_tx_ba_cb(struct sta_info *sta, int tid,
911 struct tid_ampdu_tx *tid_tx)
912 {
913 struct ieee80211_sub_if_data *sdata = sta->sdata;
914 bool send_delba = false;
915 bool start_txq = false;
916
917 ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n",
918 sta->sta.addr, tid);
919
920 spin_lock_bh(&sta->lock);
921
922 if (!test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
923 ht_dbg(sdata,
924 "unexpected callback to A-MPDU stop for %pM tid %d\n",
925 sta->sta.addr, tid);
926 goto unlock_sta;
927 }
928
929 if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
930 send_delba = true;
931
932 ieee80211_remove_tid_tx(sta, tid);
933 start_txq = true;
934
935 unlock_sta:
936 spin_unlock_bh(&sta->lock);
937
938 if (start_txq)
939 ieee80211_agg_start_txq(sta, tid, false);
940
941 if (send_delba)
942 ieee80211_send_delba(sdata, sta->sta.addr, tid,
943 WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
944 }
945
ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif * vif,const u8 * ra,u16 tid)946 void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
947 const u8 *ra, u16 tid)
948 {
949 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
950 struct ieee80211_local *local = sdata->local;
951 struct sta_info *sta;
952 struct tid_ampdu_tx *tid_tx;
953
954 trace_api_stop_tx_ba_cb(sdata, ra, tid);
955
956 rcu_read_lock();
957 tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
958 if (!tid_tx)
959 goto out;
960
961 set_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state);
962 wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
963 out:
964 rcu_read_unlock();
965 }
966 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
967
968
ieee80211_process_addba_resp(struct ieee80211_local * local,struct sta_info * sta,struct ieee80211_mgmt * mgmt,size_t len)969 void ieee80211_process_addba_resp(struct ieee80211_local *local,
970 struct sta_info *sta,
971 struct ieee80211_mgmt *mgmt,
972 size_t len)
973 {
974 struct tid_ampdu_tx *tid_tx;
975 struct ieee80211_txq *txq;
976 u16 capab, tid, buf_size;
977 bool amsdu;
978
979 lockdep_assert_wiphy(sta->local->hw.wiphy);
980
981 capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
982 amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK;
983 tid = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_TID_MASK);
984 buf_size = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
985
986 ieee80211_retrieve_addba_ext_data(sta,
987 mgmt->u.action.u.addba_resp.variable,
988 len - offsetof(typeof(*mgmt),
989 u.action.u.addba_resp.variable),
990 &buf_size);
991
992 buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes);
993
994 txq = sta->sta.txq[tid];
995 if (!amsdu && txq)
996 set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags);
997
998 tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
999 if (!tid_tx)
1000 return;
1001
1002 if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
1003 ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n",
1004 sta->sta.addr, tid);
1005 return;
1006 }
1007
1008 timer_delete_sync(&tid_tx->addba_resp_timer);
1009
1010 ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n",
1011 sta->sta.addr, tid);
1012
1013 /*
1014 * addba_resp_timer may have fired before we got here, and
1015 * caused WANT_STOP to be set. If the stop then was already
1016 * processed further, STOPPING might be set.
1017 */
1018 if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) ||
1019 test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
1020 ht_dbg(sta->sdata,
1021 "got addBA resp for %pM tid %d but we already gave up\n",
1022 sta->sta.addr, tid);
1023 return;
1024 }
1025
1026 /*
1027 * IEEE 802.11-2007 7.3.1.14:
1028 * In an ADDBA Response frame, when the Status Code field
1029 * is set to 0, the Buffer Size subfield is set to a value
1030 * of at least 1.
1031 */
1032 if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
1033 == WLAN_STATUS_SUCCESS && buf_size) {
1034 if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
1035 &tid_tx->state)) {
1036 /* ignore duplicate response */
1037 return;
1038 }
1039
1040 tid_tx->buf_size = buf_size;
1041 tid_tx->amsdu = amsdu;
1042
1043 if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
1044 ieee80211_agg_tx_operational(local, sta, tid);
1045
1046 sta->ampdu_mlme.addba_req_num[tid] = 0;
1047
1048 tid_tx->timeout =
1049 le16_to_cpu(mgmt->u.action.u.addba_resp.timeout);
1050
1051 if (tid_tx->timeout) {
1052 mod_timer(&tid_tx->session_timer,
1053 TU_TO_EXP_TIME(tid_tx->timeout));
1054 tid_tx->last_tx = jiffies;
1055 }
1056
1057 } else {
1058 __ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED);
1059 }
1060 }
1061