Merge tag 'io_uring-6.5-2023-07-21' of git://git.kernel.dk/linux
[platform/kernel/linux-starfive.git] / net / mac80211 / agg-rx.c
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) 2018-2022 Intel Corporation
13  */
14
15 /**
16  * DOC: RX A-MPDU aggregation
17  *
18  * Aggregation on the RX side requires only implementing the
19  * @ampdu_action callback that is invoked to start/stop any
20  * block-ack sessions for RX aggregation.
21  *
22  * When RX aggregation is started by the peer, the driver is
23  * notified via @ampdu_action function, with the
24  * %IEEE80211_AMPDU_RX_START action, and may reject the request
25  * in which case a negative response is sent to the peer, if it
26  * accepts it a positive response is sent.
27  *
28  * While the session is active, the device/driver are required
29  * to de-aggregate frames and pass them up one by one to mac80211,
30  * which will handle the reorder buffer.
31  *
32  * When the aggregation session is stopped again by the peer or
33  * ourselves, the driver's @ampdu_action function will be called
34  * with the action %IEEE80211_AMPDU_RX_STOP. In this case, the
35  * call must not fail.
36  */
37
38 #include <linux/ieee80211.h>
39 #include <linux/slab.h>
40 #include <linux/export.h>
41 #include <net/mac80211.h>
42 #include "ieee80211_i.h"
43 #include "driver-ops.h"
44
45 static void ieee80211_free_tid_rx(struct rcu_head *h)
46 {
47         struct tid_ampdu_rx *tid_rx =
48                 container_of(h, struct tid_ampdu_rx, rcu_head);
49         int i;
50
51         for (i = 0; i < tid_rx->buf_size; i++)
52                 __skb_queue_purge(&tid_rx->reorder_buf[i]);
53         kfree(tid_rx->reorder_buf);
54         kfree(tid_rx->reorder_time);
55         kfree(tid_rx);
56 }
57
58 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
59                                      u16 initiator, u16 reason, bool tx)
60 {
61         struct ieee80211_local *local = sta->local;
62         struct tid_ampdu_rx *tid_rx;
63         struct ieee80211_ampdu_params params = {
64                 .sta = &sta->sta,
65                 .action = IEEE80211_AMPDU_RX_STOP,
66                 .tid = tid,
67                 .amsdu = false,
68                 .timeout = 0,
69                 .ssn = 0,
70         };
71
72         lockdep_assert_held(&sta->ampdu_mlme.mtx);
73
74         tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid],
75                                         lockdep_is_held(&sta->ampdu_mlme.mtx));
76
77         if (!test_bit(tid, sta->ampdu_mlme.agg_session_valid))
78                 return;
79
80         RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL);
81         __clear_bit(tid, sta->ampdu_mlme.agg_session_valid);
82
83         ht_dbg(sta->sdata,
84                "Rx BA session stop requested for %pM tid %u %s reason: %d\n",
85                sta->sta.addr, tid,
86                initiator == WLAN_BACK_RECIPIENT ? "recipient" : "initiator",
87                (int)reason);
88
89         if (drv_ampdu_action(local, sta->sdata, &params))
90                 sdata_info(sta->sdata,
91                            "HW problem - can not stop rx aggregation for %pM tid %d\n",
92                            sta->sta.addr, tid);
93
94         /* check if this is a self generated aggregation halt */
95         if (initiator == WLAN_BACK_RECIPIENT && tx)
96                 ieee80211_send_delba(sta->sdata, sta->sta.addr,
97                                      tid, WLAN_BACK_RECIPIENT, reason);
98
99         /*
100          * return here in case tid_rx is not assigned - which will happen if
101          * IEEE80211_HW_SUPPORTS_REORDERING_BUFFER is set.
102          */
103         if (!tid_rx)
104                 return;
105
106         del_timer_sync(&tid_rx->session_timer);
107
108         /* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */
109         spin_lock_bh(&tid_rx->reorder_lock);
110         tid_rx->removed = true;
111         spin_unlock_bh(&tid_rx->reorder_lock);
112         del_timer_sync(&tid_rx->reorder_timer);
113
114         call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx);
115 }
116
117 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
118                                     u16 initiator, u16 reason, bool tx)
119 {
120         mutex_lock(&sta->ampdu_mlme.mtx);
121         ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx);
122         mutex_unlock(&sta->ampdu_mlme.mtx);
123 }
124
125 void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap,
126                                   const u8 *addr)
127 {
128         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
129         struct sta_info *sta;
130         int i;
131
132         rcu_read_lock();
133         sta = sta_info_get_bss(sdata, addr);
134         if (!sta) {
135                 rcu_read_unlock();
136                 return;
137         }
138
139         for (i = 0; i < IEEE80211_NUM_TIDS; i++)
140                 if (ba_rx_bitmap & BIT(i))
141                         set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested);
142
143         ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
144         rcu_read_unlock();
145 }
146 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session);
147
148 /*
149  * After accepting the AddBA Request we activated a timer,
150  * resetting it after each frame that arrives from the originator.
151  */
152 static void sta_rx_agg_session_timer_expired(struct timer_list *t)
153 {
154         struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, session_timer);
155         struct sta_info *sta = tid_rx->sta;
156         u8 tid = tid_rx->tid;
157         unsigned long timeout;
158
159         timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout);
160         if (time_is_after_jiffies(timeout)) {
161                 mod_timer(&tid_rx->session_timer, timeout);
162                 return;
163         }
164
165         ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n",
166                sta->sta.addr, tid);
167
168         set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
169         ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
170 }
171
172 static void sta_rx_agg_reorder_timer_expired(struct timer_list *t)
173 {
174         struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, reorder_timer);
175
176         rcu_read_lock();
177         ieee80211_release_reorder_timeout(tid_rx->sta, tid_rx->tid);
178         rcu_read_unlock();
179 }
180
181 static void ieee80211_add_addbaext(struct ieee80211_sub_if_data *sdata,
182                                    struct sk_buff *skb,
183                                    const struct ieee80211_addba_ext_ie *req,
184                                    u16 buf_size)
185 {
186         struct ieee80211_addba_ext_ie *resp;
187         u8 *pos;
188
189         pos = skb_put_zero(skb, 2 + sizeof(struct ieee80211_addba_ext_ie));
190         *pos++ = WLAN_EID_ADDBA_EXT;
191         *pos++ = sizeof(struct ieee80211_addba_ext_ie);
192         resp = (struct ieee80211_addba_ext_ie *)pos;
193         resp->data = req->data & IEEE80211_ADDBA_EXT_NO_FRAG;
194
195         resp->data |= u8_encode_bits(buf_size >> IEEE80211_ADDBA_EXT_BUF_SIZE_SHIFT,
196                                      IEEE80211_ADDBA_EXT_BUF_SIZE_MASK);
197 }
198
199 static void ieee80211_send_addba_resp(struct sta_info *sta, u8 *da, u16 tid,
200                                       u8 dialog_token, u16 status, u16 policy,
201                                       u16 buf_size, u16 timeout,
202                                       const struct ieee80211_addba_ext_ie *addbaext)
203 {
204         struct ieee80211_sub_if_data *sdata = sta->sdata;
205         struct ieee80211_local *local = sdata->local;
206         struct sk_buff *skb;
207         struct ieee80211_mgmt *mgmt;
208         bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU);
209         u16 capab;
210
211         skb = dev_alloc_skb(sizeof(*mgmt) +
212                     2 + sizeof(struct ieee80211_addba_ext_ie) +
213                     local->hw.extra_tx_headroom);
214         if (!skb)
215                 return;
216
217         skb_reserve(skb, local->hw.extra_tx_headroom);
218         mgmt = skb_put_zero(skb, 24);
219         memcpy(mgmt->da, da, ETH_ALEN);
220         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
221         if (sdata->vif.type == NL80211_IFTYPE_AP ||
222             sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
223             sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
224                 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
225         else if (sdata->vif.type == NL80211_IFTYPE_STATION)
226                 memcpy(mgmt->bssid, sdata->vif.cfg.ap_addr, ETH_ALEN);
227         else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
228                 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
229
230         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
231                                           IEEE80211_STYPE_ACTION);
232
233         skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
234         mgmt->u.action.category = WLAN_CATEGORY_BACK;
235         mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
236         mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
237
238         capab = u16_encode_bits(amsdu, IEEE80211_ADDBA_PARAM_AMSDU_MASK);
239         capab |= u16_encode_bits(policy, IEEE80211_ADDBA_PARAM_POLICY_MASK);
240         capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
241         capab |= u16_encode_bits(buf_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
242
243         mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
244         mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
245         mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
246
247         if (sta->sta.deflink.he_cap.has_he && addbaext)
248                 ieee80211_add_addbaext(sdata, skb, addbaext, buf_size);
249
250         ieee80211_tx_skb(sdata, skb);
251 }
252
253 void ___ieee80211_start_rx_ba_session(struct sta_info *sta,
254                                       u8 dialog_token, u16 timeout,
255                                       u16 start_seq_num, u16 ba_policy, u16 tid,
256                                       u16 buf_size, bool tx, bool auto_seq,
257                                       const struct ieee80211_addba_ext_ie *addbaext)
258 {
259         struct ieee80211_local *local = sta->sdata->local;
260         struct tid_ampdu_rx *tid_agg_rx;
261         struct ieee80211_ampdu_params params = {
262                 .sta = &sta->sta,
263                 .action = IEEE80211_AMPDU_RX_START,
264                 .tid = tid,
265                 .amsdu = false,
266                 .timeout = timeout,
267                 .ssn = start_seq_num,
268         };
269         int i, ret = -EOPNOTSUPP;
270         u16 status = WLAN_STATUS_REQUEST_DECLINED;
271         u16 max_buf_size;
272
273         if (tid >= IEEE80211_FIRST_TSPEC_TSID) {
274                 ht_dbg(sta->sdata,
275                        "STA %pM requests BA session on unsupported tid %d\n",
276                        sta->sta.addr, tid);
277                 goto end;
278         }
279
280         if (!sta->sta.deflink.ht_cap.ht_supported &&
281             !sta->sta.deflink.he_cap.has_he) {
282                 ht_dbg(sta->sdata,
283                        "STA %pM erroneously requests BA session on tid %d w/o HT\n",
284                        sta->sta.addr, tid);
285                 /* send a response anyway, it's an error case if we get here */
286                 goto end;
287         }
288
289         if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
290                 ht_dbg(sta->sdata,
291                        "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
292                        sta->sta.addr, tid);
293                 goto end;
294         }
295
296         if (sta->sta.deflink.eht_cap.has_eht)
297                 max_buf_size = IEEE80211_MAX_AMPDU_BUF_EHT;
298         else if (sta->sta.deflink.he_cap.has_he)
299                 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HE;
300         else
301                 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
302
303         /* sanity check for incoming parameters:
304          * check if configuration can support the BA policy
305          * and if buffer size does not exceeds max value */
306         /* XXX: check own ht delayed BA capability?? */
307         if (((ba_policy != 1) &&
308              (!(sta->sta.deflink.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
309             (buf_size > max_buf_size)) {
310                 status = WLAN_STATUS_INVALID_QOS_PARAM;
311                 ht_dbg_ratelimited(sta->sdata,
312                                    "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
313                                    sta->sta.addr, tid, ba_policy, buf_size);
314                 goto end;
315         }
316         /* determine default buffer size */
317         if (buf_size == 0)
318                 buf_size = max_buf_size;
319
320         /* make sure the size doesn't exceed the maximum supported by the hw */
321         if (buf_size > sta->sta.max_rx_aggregation_subframes)
322                 buf_size = sta->sta.max_rx_aggregation_subframes;
323         params.buf_size = buf_size;
324
325         ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
326                buf_size, sta->sta.addr);
327
328         /* examine state machine */
329         lockdep_assert_held(&sta->ampdu_mlme.mtx);
330
331         if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) {
332                 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) {
333                         struct tid_ampdu_rx *tid_rx;
334
335                         ht_dbg_ratelimited(sta->sdata,
336                                            "updated AddBA Req from %pM on tid %u\n",
337                                            sta->sta.addr, tid);
338                         /* We have no API to update the timeout value in the
339                          * driver so reject the timeout update if the timeout
340                          * changed. If it did not change, i.e., no real update,
341                          * just reply with success.
342                          */
343                         rcu_read_lock();
344                         tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
345                         if (tid_rx && tid_rx->timeout == timeout)
346                                 status = WLAN_STATUS_SUCCESS;
347                         else
348                                 status = WLAN_STATUS_REQUEST_DECLINED;
349                         rcu_read_unlock();
350                         goto end;
351                 }
352
353                 ht_dbg_ratelimited(sta->sdata,
354                                    "unexpected AddBA Req from %pM on tid %u\n",
355                                    sta->sta.addr, tid);
356
357                 /* delete existing Rx BA session on the same tid */
358                 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
359                                                 WLAN_STATUS_UNSPECIFIED_QOS,
360                                                 false);
361         }
362
363         if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) {
364                 ret = drv_ampdu_action(local, sta->sdata, &params);
365                 ht_dbg(sta->sdata,
366                        "Rx A-MPDU request on %pM tid %d result %d\n",
367                        sta->sta.addr, tid, ret);
368                 if (!ret)
369                         status = WLAN_STATUS_SUCCESS;
370                 goto end;
371         }
372
373         /* prepare A-MPDU MLME for Rx aggregation */
374         tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL);
375         if (!tid_agg_rx)
376                 goto end;
377
378         spin_lock_init(&tid_agg_rx->reorder_lock);
379
380         /* rx timer */
381         timer_setup(&tid_agg_rx->session_timer,
382                     sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE);
383
384         /* rx reorder timer */
385         timer_setup(&tid_agg_rx->reorder_timer,
386                     sta_rx_agg_reorder_timer_expired, 0);
387
388         /* prepare reordering buffer */
389         tid_agg_rx->reorder_buf =
390                 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
391         tid_agg_rx->reorder_time =
392                 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
393         if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
394                 kfree(tid_agg_rx->reorder_buf);
395                 kfree(tid_agg_rx->reorder_time);
396                 kfree(tid_agg_rx);
397                 goto end;
398         }
399
400         for (i = 0; i < buf_size; i++)
401                 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
402
403         ret = drv_ampdu_action(local, sta->sdata, &params);
404         ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
405                sta->sta.addr, tid, ret);
406         if (ret) {
407                 kfree(tid_agg_rx->reorder_buf);
408                 kfree(tid_agg_rx->reorder_time);
409                 kfree(tid_agg_rx);
410                 goto end;
411         }
412
413         /* update data */
414         tid_agg_rx->ssn = start_seq_num;
415         tid_agg_rx->head_seq_num = start_seq_num;
416         tid_agg_rx->buf_size = buf_size;
417         tid_agg_rx->timeout = timeout;
418         tid_agg_rx->stored_mpdu_num = 0;
419         tid_agg_rx->auto_seq = auto_seq;
420         tid_agg_rx->started = false;
421         tid_agg_rx->reorder_buf_filtered = 0;
422         tid_agg_rx->tid = tid;
423         tid_agg_rx->sta = sta;
424         status = WLAN_STATUS_SUCCESS;
425
426         /* activate it for RX */
427         rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
428
429         if (timeout) {
430                 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
431                 tid_agg_rx->last_rx = jiffies;
432         }
433
434 end:
435         if (status == WLAN_STATUS_SUCCESS) {
436                 __set_bit(tid, sta->ampdu_mlme.agg_session_valid);
437                 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg);
438                 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token;
439         }
440
441         if (tx)
442                 ieee80211_send_addba_resp(sta, sta->sta.addr, tid,
443                                           dialog_token, status, 1, buf_size,
444                                           timeout, addbaext);
445 }
446
447 static void __ieee80211_start_rx_ba_session(struct sta_info *sta,
448                                             u8 dialog_token, u16 timeout,
449                                             u16 start_seq_num, u16 ba_policy,
450                                             u16 tid, u16 buf_size, bool tx,
451                                             bool auto_seq,
452                                             const struct ieee80211_addba_ext_ie *addbaext)
453 {
454         mutex_lock(&sta->ampdu_mlme.mtx);
455         ___ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
456                                          start_seq_num, ba_policy, tid,
457                                          buf_size, tx, auto_seq, addbaext);
458         mutex_unlock(&sta->ampdu_mlme.mtx);
459 }
460
461 void ieee80211_process_addba_request(struct ieee80211_local *local,
462                                      struct sta_info *sta,
463                                      struct ieee80211_mgmt *mgmt,
464                                      size_t len)
465 {
466         u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
467         struct ieee802_11_elems *elems = NULL;
468         u8 dialog_token;
469         int ies_len;
470
471         /* extract session parameters from addba request frame */
472         dialog_token = mgmt->u.action.u.addba_req.dialog_token;
473         timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
474         start_seq_num =
475                 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
476
477         capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
478         ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
479         tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
480         buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
481
482         ies_len = len - offsetof(struct ieee80211_mgmt,
483                                  u.action.u.addba_req.variable);
484         if (ies_len) {
485                 elems = ieee802_11_parse_elems(mgmt->u.action.u.addba_req.variable,
486                                                ies_len, true, NULL);
487                 if (!elems || elems->parse_error)
488                         goto free;
489         }
490
491         if (sta->sta.deflink.eht_cap.has_eht && elems && elems->addba_ext_ie) {
492                 u8 buf_size_1k = u8_get_bits(elems->addba_ext_ie->data,
493                                              IEEE80211_ADDBA_EXT_BUF_SIZE_MASK);
494
495                 buf_size |= buf_size_1k << IEEE80211_ADDBA_EXT_BUF_SIZE_SHIFT;
496         }
497
498         __ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
499                                         start_seq_num, ba_policy, tid,
500                                         buf_size, true, false,
501                                         elems ? elems->addba_ext_ie : NULL);
502 free:
503         kfree(elems);
504 }
505
506 void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif,
507                                  const u8 *addr, unsigned int tid)
508 {
509         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
510         struct ieee80211_local *local = sdata->local;
511         struct sta_info *sta;
512
513         rcu_read_lock();
514         sta = sta_info_get_bss(sdata, addr);
515         if (!sta)
516                 goto unlock;
517
518         set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl);
519         ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
520  unlock:
521         rcu_read_unlock();
522 }
523 EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl);
524
525 void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif,
526                                    const u8 *addr, unsigned int tid)
527 {
528         struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
529         struct ieee80211_local *local = sdata->local;
530         struct sta_info *sta;
531
532         rcu_read_lock();
533         sta = sta_info_get_bss(sdata, addr);
534         if (!sta)
535                 goto unlock;
536
537         set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
538         ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
539
540  unlock:
541         rcu_read_unlock();
542 }
543 EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired);