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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/**
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
45static 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
58void ___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, ¶ms))
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
117void __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
125void 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}
146EXPORT_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 */
152static 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
172static 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
181static void ieee80211_add_addbaext(struct ieee80211_sub_if_data *sdata,
182 struct sk_buff *skb,
183 const struct ieee80211_addba_ext_ie *req)
184{
185 struct ieee80211_supported_band *sband;
186 struct ieee80211_addba_ext_ie *resp;
187 const struct ieee80211_sta_he_cap *he_cap;
188 u8 frag_level, cap_frag_level;
189 u8 *pos;
190
191 sband = ieee80211_get_sband(sdata);
192 if (!sband)
193 return;
194 he_cap = ieee80211_get_he_iftype_cap(sband, sdata->vif.type);
195 if (!he_cap)
196 return;
197
198 pos = skb_put_zero(skb, 2 + sizeof(struct ieee80211_addba_ext_ie));
199 *pos++ = WLAN_EID_ADDBA_EXT;
200 *pos++ = sizeof(struct ieee80211_addba_ext_ie);
201 resp = (struct ieee80211_addba_ext_ie *)pos;
202 resp->data = req->data & IEEE80211_ADDBA_EXT_NO_FRAG;
203
204 frag_level = u32_get_bits(req->data,
205 IEEE80211_ADDBA_EXT_FRAG_LEVEL_MASK);
206 cap_frag_level = u32_get_bits(he_cap->he_cap_elem.mac_cap_info[0],
207 IEEE80211_HE_MAC_CAP0_DYNAMIC_FRAG_MASK);
208 if (frag_level > cap_frag_level)
209 frag_level = cap_frag_level;
210 resp->data |= u8_encode_bits(frag_level,
211 IEEE80211_ADDBA_EXT_FRAG_LEVEL_MASK);
212}
213
214static void ieee80211_send_addba_resp(struct sta_info *sta, u8 *da, u16 tid,
215 u8 dialog_token, u16 status, u16 policy,
216 u16 buf_size, u16 timeout,
217 const struct ieee80211_addba_ext_ie *addbaext)
218{
219 struct ieee80211_sub_if_data *sdata = sta->sdata;
220 struct ieee80211_local *local = sdata->local;
221 struct sk_buff *skb;
222 struct ieee80211_mgmt *mgmt;
223 bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU);
224 u16 capab;
225
226 skb = dev_alloc_skb(sizeof(*mgmt) +
227 2 + sizeof(struct ieee80211_addba_ext_ie) +
228 local->hw.extra_tx_headroom);
229 if (!skb)
230 return;
231
232 skb_reserve(skb, local->hw.extra_tx_headroom);
233 mgmt = skb_put_zero(skb, 24);
234 memcpy(mgmt->da, da, ETH_ALEN);
235 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
236 if (sdata->vif.type == NL80211_IFTYPE_AP ||
237 sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
238 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
239 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
240 else if (sdata->vif.type == NL80211_IFTYPE_STATION)
241 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
242 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
243 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
244
245 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
246 IEEE80211_STYPE_ACTION);
247
248 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
249 mgmt->u.action.category = WLAN_CATEGORY_BACK;
250 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
251 mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
252
253 capab = u16_encode_bits(amsdu, IEEE80211_ADDBA_PARAM_AMSDU_MASK);
254 capab |= u16_encode_bits(policy, IEEE80211_ADDBA_PARAM_POLICY_MASK);
255 capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
256 capab |= u16_encode_bits(buf_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
257
258 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
259 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
260 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
261
262 if (sta->sta.he_cap.has_he && addbaext)
263 ieee80211_add_addbaext(sdata, skb, addbaext);
264
265 ieee80211_tx_skb(sdata, skb);
266}
267
268void ___ieee80211_start_rx_ba_session(struct sta_info *sta,
269 u8 dialog_token, u16 timeout,
270 u16 start_seq_num, u16 ba_policy, u16 tid,
271 u16 buf_size, bool tx, bool auto_seq,
272 const struct ieee80211_addba_ext_ie *addbaext)
273{
274 struct ieee80211_local *local = sta->sdata->local;
275 struct tid_ampdu_rx *tid_agg_rx;
276 struct ieee80211_ampdu_params params = {
277 .sta = &sta->sta,
278 .action = IEEE80211_AMPDU_RX_START,
279 .tid = tid,
280 .amsdu = false,
281 .timeout = timeout,
282 .ssn = start_seq_num,
283 };
284 int i, ret = -EOPNOTSUPP;
285 u16 status = WLAN_STATUS_REQUEST_DECLINED;
286 u16 max_buf_size;
287
288 if (tid >= IEEE80211_FIRST_TSPEC_TSID) {
289 ht_dbg(sta->sdata,
290 "STA %pM requests BA session on unsupported tid %d\n",
291 sta->sta.addr, tid);
292 goto end;
293 }
294
295 if (!sta->sta.ht_cap.ht_supported &&
296 sta->sdata->vif.bss_conf.chandef.chan->band != NL80211_BAND_6GHZ) {
297 ht_dbg(sta->sdata,
298 "STA %pM erroneously requests BA session on tid %d w/o QoS\n",
299 sta->sta.addr, tid);
300 /* send a response anyway, it's an error case if we get here */
301 goto end;
302 }
303
304 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
305 ht_dbg(sta->sdata,
306 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
307 sta->sta.addr, tid);
308 goto end;
309 }
310
311 if (sta->sta.he_cap.has_he)
312 max_buf_size = IEEE80211_MAX_AMPDU_BUF;
313 else
314 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
315
316 /* sanity check for incoming parameters:
317 * check if configuration can support the BA policy
318 * and if buffer size does not exceeds max value */
319 /* XXX: check own ht delayed BA capability?? */
320 if (((ba_policy != 1) &&
321 (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
322 (buf_size > max_buf_size)) {
323 status = WLAN_STATUS_INVALID_QOS_PARAM;
324 ht_dbg_ratelimited(sta->sdata,
325 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
326 sta->sta.addr, tid, ba_policy, buf_size);
327 goto end;
328 }
329 /* determine default buffer size */
330 if (buf_size == 0)
331 buf_size = max_buf_size;
332
333 /* make sure the size doesn't exceed the maximum supported by the hw */
334 if (buf_size > sta->sta.max_rx_aggregation_subframes)
335 buf_size = sta->sta.max_rx_aggregation_subframes;
336 params.buf_size = buf_size;
337
338 ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
339 buf_size, sta->sta.addr);
340
341 /* examine state machine */
342 lockdep_assert_held(&sta->ampdu_mlme.mtx);
343
344 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) {
345 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) {
346 struct tid_ampdu_rx *tid_rx;
347
348 ht_dbg_ratelimited(sta->sdata,
349 "updated AddBA Req from %pM on tid %u\n",
350 sta->sta.addr, tid);
351 /* We have no API to update the timeout value in the
352 * driver so reject the timeout update if the timeout
353 * changed. If it did not change, i.e., no real update,
354 * just reply with success.
355 */
356 rcu_read_lock();
357 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
358 if (tid_rx && tid_rx->timeout == timeout)
359 status = WLAN_STATUS_SUCCESS;
360 else
361 status = WLAN_STATUS_REQUEST_DECLINED;
362 rcu_read_unlock();
363 goto end;
364 }
365
366 ht_dbg_ratelimited(sta->sdata,
367 "unexpected AddBA Req from %pM on tid %u\n",
368 sta->sta.addr, tid);
369
370 /* delete existing Rx BA session on the same tid */
371 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
372 WLAN_STATUS_UNSPECIFIED_QOS,
373 false);
374 }
375
376 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) {
377 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
378 ht_dbg(sta->sdata,
379 "Rx A-MPDU request on %pM tid %d result %d\n",
380 sta->sta.addr, tid, ret);
381 if (!ret)
382 status = WLAN_STATUS_SUCCESS;
383 goto end;
384 }
385
386 /* prepare A-MPDU MLME for Rx aggregation */
387 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL);
388 if (!tid_agg_rx)
389 goto end;
390
391 spin_lock_init(&tid_agg_rx->reorder_lock);
392
393 /* rx timer */
394 timer_setup(&tid_agg_rx->session_timer,
395 sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE);
396
397 /* rx reorder timer */
398 timer_setup(&tid_agg_rx->reorder_timer,
399 sta_rx_agg_reorder_timer_expired, 0);
400
401 /* prepare reordering buffer */
402 tid_agg_rx->reorder_buf =
403 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
404 tid_agg_rx->reorder_time =
405 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
406 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
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 for (i = 0; i < buf_size; i++)
414 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
415
416 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
417 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
418 sta->sta.addr, tid, ret);
419 if (ret) {
420 kfree(tid_agg_rx->reorder_buf);
421 kfree(tid_agg_rx->reorder_time);
422 kfree(tid_agg_rx);
423 goto end;
424 }
425
426 /* update data */
427 tid_agg_rx->ssn = start_seq_num;
428 tid_agg_rx->head_seq_num = start_seq_num;
429 tid_agg_rx->buf_size = buf_size;
430 tid_agg_rx->timeout = timeout;
431 tid_agg_rx->stored_mpdu_num = 0;
432 tid_agg_rx->auto_seq = auto_seq;
433 tid_agg_rx->started = false;
434 tid_agg_rx->reorder_buf_filtered = 0;
435 tid_agg_rx->tid = tid;
436 tid_agg_rx->sta = sta;
437 status = WLAN_STATUS_SUCCESS;
438
439 /* activate it for RX */
440 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
441
442 if (timeout) {
443 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
444 tid_agg_rx->last_rx = jiffies;
445 }
446
447end:
448 if (status == WLAN_STATUS_SUCCESS) {
449 __set_bit(tid, sta->ampdu_mlme.agg_session_valid);
450 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg);
451 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token;
452 }
453
454 if (tx)
455 ieee80211_send_addba_resp(sta, sta->sta.addr, tid,
456 dialog_token, status, 1, buf_size,
457 timeout, addbaext);
458}
459
460static void __ieee80211_start_rx_ba_session(struct sta_info *sta,
461 u8 dialog_token, u16 timeout,
462 u16 start_seq_num, u16 ba_policy,
463 u16 tid, u16 buf_size, bool tx,
464 bool auto_seq,
465 const struct ieee80211_addba_ext_ie *addbaext)
466{
467 mutex_lock(&sta->ampdu_mlme.mtx);
468 ___ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
469 start_seq_num, ba_policy, tid,
470 buf_size, tx, auto_seq, addbaext);
471 mutex_unlock(&sta->ampdu_mlme.mtx);
472}
473
474void ieee80211_process_addba_request(struct ieee80211_local *local,
475 struct sta_info *sta,
476 struct ieee80211_mgmt *mgmt,
477 size_t len)
478{
479 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
480 struct ieee802_11_elems elems = { };
481 u8 dialog_token;
482 int ies_len;
483
484 /* extract session parameters from addba request frame */
485 dialog_token = mgmt->u.action.u.addba_req.dialog_token;
486 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
487 start_seq_num =
488 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
489
490 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
491 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
492 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
493 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
494
495 ies_len = len - offsetof(struct ieee80211_mgmt,
496 u.action.u.addba_req.variable);
497 if (ies_len) {
498 ieee802_11_parse_elems(mgmt->u.action.u.addba_req.variable,
499 ies_len, true, &elems, mgmt->bssid, NULL);
500 if (elems.parse_error)
501 return;
502 }
503
504 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
505 start_seq_num, ba_policy, tid,
506 buf_size, true, false,
507 elems.addba_ext_ie);
508}
509
510void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif,
511 const u8 *addr, unsigned int tid)
512{
513 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
514 struct ieee80211_local *local = sdata->local;
515 struct sta_info *sta;
516
517 rcu_read_lock();
518 sta = sta_info_get_bss(sdata, addr);
519 if (!sta)
520 goto unlock;
521
522 set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl);
523 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
524 unlock:
525 rcu_read_unlock();
526}
527EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl);
528
529void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif,
530 const u8 *addr, unsigned int tid)
531{
532 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
533 struct ieee80211_local *local = sdata->local;
534 struct sta_info *sta;
535
536 rcu_read_lock();
537 sta = sta_info_get_bss(sdata, addr);
538 if (!sta)
539 goto unlock;
540
541 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
542 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
543
544 unlock:
545 rcu_read_unlock();
546}
547EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired);
1/*
2 * HT handling
3 *
4 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
5 * Copyright 2002-2005, Instant802 Networks, Inc.
6 * Copyright 2005-2006, Devicescape Software, Inc.
7 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
8 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
9 * Copyright 2007-2010, Intel Corporation
10 * Copyright(c) 2015 Intel Deutschland GmbH
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
15 */
16
17/**
18 * DOC: RX A-MPDU aggregation
19 *
20 * Aggregation on the RX side requires only implementing the
21 * @ampdu_action callback that is invoked to start/stop any
22 * block-ack sessions for RX aggregation.
23 *
24 * When RX aggregation is started by the peer, the driver is
25 * notified via @ampdu_action function, with the
26 * %IEEE80211_AMPDU_RX_START action, and may reject the request
27 * in which case a negative response is sent to the peer, if it
28 * accepts it a positive response is sent.
29 *
30 * While the session is active, the device/driver are required
31 * to de-aggregate frames and pass them up one by one to mac80211,
32 * which will handle the reorder buffer.
33 *
34 * When the aggregation session is stopped again by the peer or
35 * ourselves, the driver's @ampdu_action function will be called
36 * with the action %IEEE80211_AMPDU_RX_STOP. In this case, the
37 * call must not fail.
38 */
39
40#include <linux/ieee80211.h>
41#include <linux/slab.h>
42#include <linux/export.h>
43#include <net/mac80211.h>
44#include "ieee80211_i.h"
45#include "driver-ops.h"
46
47static void ieee80211_free_tid_rx(struct rcu_head *h)
48{
49 struct tid_ampdu_rx *tid_rx =
50 container_of(h, struct tid_ampdu_rx, rcu_head);
51 int i;
52
53 for (i = 0; i < tid_rx->buf_size; i++)
54 __skb_queue_purge(&tid_rx->reorder_buf[i]);
55 kfree(tid_rx->reorder_buf);
56 kfree(tid_rx->reorder_time);
57 kfree(tid_rx);
58}
59
60void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
61 u16 initiator, u16 reason, bool tx)
62{
63 struct ieee80211_local *local = sta->local;
64 struct tid_ampdu_rx *tid_rx;
65 struct ieee80211_ampdu_params params = {
66 .sta = &sta->sta,
67 .action = IEEE80211_AMPDU_RX_STOP,
68 .tid = tid,
69 .amsdu = false,
70 .timeout = 0,
71 .ssn = 0,
72 };
73
74 lockdep_assert_held(&sta->ampdu_mlme.mtx);
75
76 tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid],
77 lockdep_is_held(&sta->ampdu_mlme.mtx));
78
79 if (!test_bit(tid, sta->ampdu_mlme.agg_session_valid))
80 return;
81
82 RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL);
83 __clear_bit(tid, sta->ampdu_mlme.agg_session_valid);
84
85 ht_dbg(sta->sdata,
86 "Rx BA session stop requested for %pM tid %u %s reason: %d\n",
87 sta->sta.addr, tid,
88 initiator == WLAN_BACK_RECIPIENT ? "recipient" : "inititator",
89 (int)reason);
90
91 if (drv_ampdu_action(local, sta->sdata, ¶ms))
92 sdata_info(sta->sdata,
93 "HW problem - can not stop rx aggregation for %pM tid %d\n",
94 sta->sta.addr, tid);
95
96 /* check if this is a self generated aggregation halt */
97 if (initiator == WLAN_BACK_RECIPIENT && tx)
98 ieee80211_send_delba(sta->sdata, sta->sta.addr,
99 tid, WLAN_BACK_RECIPIENT, reason);
100
101 /*
102 * return here in case tid_rx is not assigned - which will happen if
103 * IEEE80211_HW_SUPPORTS_REORDERING_BUFFER is set.
104 */
105 if (!tid_rx)
106 return;
107
108 del_timer_sync(&tid_rx->session_timer);
109
110 /* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */
111 spin_lock_bh(&tid_rx->reorder_lock);
112 tid_rx->removed = true;
113 spin_unlock_bh(&tid_rx->reorder_lock);
114 del_timer_sync(&tid_rx->reorder_timer);
115
116 call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx);
117}
118
119void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
120 u16 initiator, u16 reason, bool tx)
121{
122 mutex_lock(&sta->ampdu_mlme.mtx);
123 ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx);
124 mutex_unlock(&sta->ampdu_mlme.mtx);
125}
126
127void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap,
128 const u8 *addr)
129{
130 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
131 struct sta_info *sta;
132 int i;
133
134 rcu_read_lock();
135 sta = sta_info_get_bss(sdata, addr);
136 if (!sta) {
137 rcu_read_unlock();
138 return;
139 }
140
141 for (i = 0; i < IEEE80211_NUM_TIDS; i++)
142 if (ba_rx_bitmap & BIT(i))
143 set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested);
144
145 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
146 rcu_read_unlock();
147}
148EXPORT_SYMBOL(ieee80211_stop_rx_ba_session);
149
150/*
151 * After accepting the AddBA Request we activated a timer,
152 * resetting it after each frame that arrives from the originator.
153 */
154static void sta_rx_agg_session_timer_expired(unsigned long data)
155{
156 /* not an elegant detour, but there is no choice as the timer passes
157 * only one argument, and various sta_info are needed here, so init
158 * flow in sta_info_create gives the TID as data, while the timer_to_id
159 * array gives the sta through container_of */
160 u8 *ptid = (u8 *)data;
161 u8 *timer_to_id = ptid - *ptid;
162 struct sta_info *sta = container_of(timer_to_id, struct sta_info,
163 timer_to_tid[0]);
164 struct tid_ampdu_rx *tid_rx;
165 unsigned long timeout;
166
167 rcu_read_lock();
168 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[*ptid]);
169 if (!tid_rx) {
170 rcu_read_unlock();
171 return;
172 }
173
174 timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout);
175 if (time_is_after_jiffies(timeout)) {
176 mod_timer(&tid_rx->session_timer, timeout);
177 rcu_read_unlock();
178 return;
179 }
180 rcu_read_unlock();
181
182 ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n",
183 sta->sta.addr, (u16)*ptid);
184
185 set_bit(*ptid, sta->ampdu_mlme.tid_rx_timer_expired);
186 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
187}
188
189static void sta_rx_agg_reorder_timer_expired(unsigned long data)
190{
191 u8 *ptid = (u8 *)data;
192 u8 *timer_to_id = ptid - *ptid;
193 struct sta_info *sta = container_of(timer_to_id, struct sta_info,
194 timer_to_tid[0]);
195
196 rcu_read_lock();
197 ieee80211_release_reorder_timeout(sta, *ptid);
198 rcu_read_unlock();
199}
200
201static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
202 u8 dialog_token, u16 status, u16 policy,
203 u16 buf_size, u16 timeout)
204{
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) + local->hw.extra_tx_headroom);
212 if (!skb)
213 return;
214
215 skb_reserve(skb, local->hw.extra_tx_headroom);
216 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
217 memset(mgmt, 0, 24);
218 memcpy(mgmt->da, da, ETH_ALEN);
219 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
220 if (sdata->vif.type == NL80211_IFTYPE_AP ||
221 sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
222 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
223 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
224 else if (sdata->vif.type == NL80211_IFTYPE_STATION)
225 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
226 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
227 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
228
229 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
230 IEEE80211_STYPE_ACTION);
231
232 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
233 mgmt->u.action.category = WLAN_CATEGORY_BACK;
234 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
235 mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
236
237 capab = (u16)(amsdu << 0); /* bit 0 A-MSDU support */
238 capab |= (u16)(policy << 1); /* bit 1 aggregation policy */
239 capab |= (u16)(tid << 2); /* bit 5:2 TID number */
240 capab |= (u16)(buf_size << 6); /* bit 15:6 max size of aggregation */
241
242 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
243 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
244 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
245
246 ieee80211_tx_skb(sdata, skb);
247}
248
249void __ieee80211_start_rx_ba_session(struct sta_info *sta,
250 u8 dialog_token, u16 timeout,
251 u16 start_seq_num, u16 ba_policy, u16 tid,
252 u16 buf_size, bool tx, bool auto_seq)
253{
254 struct ieee80211_local *local = sta->sdata->local;
255 struct tid_ampdu_rx *tid_agg_rx;
256 struct ieee80211_ampdu_params params = {
257 .sta = &sta->sta,
258 .action = IEEE80211_AMPDU_RX_START,
259 .tid = tid,
260 .amsdu = false,
261 .timeout = timeout,
262 .ssn = start_seq_num,
263 };
264
265 int i, ret = -EOPNOTSUPP;
266 u16 status = WLAN_STATUS_REQUEST_DECLINED;
267
268 if (!sta->sta.ht_cap.ht_supported) {
269 ht_dbg(sta->sdata,
270 "STA %pM erroneously requests BA session on tid %d w/o QoS\n",
271 sta->sta.addr, tid);
272 /* send a response anyway, it's an error case if we get here */
273 goto end_no_lock;
274 }
275
276 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
277 ht_dbg(sta->sdata,
278 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
279 sta->sta.addr, tid);
280 goto end_no_lock;
281 }
282
283 /* sanity check for incoming parameters:
284 * check if configuration can support the BA policy
285 * and if buffer size does not exceeds max value */
286 /* XXX: check own ht delayed BA capability?? */
287 if (((ba_policy != 1) &&
288 (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
289 (buf_size > IEEE80211_MAX_AMPDU_BUF)) {
290 status = WLAN_STATUS_INVALID_QOS_PARAM;
291 ht_dbg_ratelimited(sta->sdata,
292 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
293 sta->sta.addr, tid, ba_policy, buf_size);
294 goto end_no_lock;
295 }
296 /* determine default buffer size */
297 if (buf_size == 0)
298 buf_size = IEEE80211_MAX_AMPDU_BUF;
299
300 /* make sure the size doesn't exceed the maximum supported by the hw */
301 if (buf_size > local->hw.max_rx_aggregation_subframes)
302 buf_size = local->hw.max_rx_aggregation_subframes;
303 params.buf_size = buf_size;
304
305 /* examine state machine */
306 mutex_lock(&sta->ampdu_mlme.mtx);
307
308 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) {
309 ht_dbg_ratelimited(sta->sdata,
310 "unexpected AddBA Req from %pM on tid %u\n",
311 sta->sta.addr, tid);
312
313 /* delete existing Rx BA session on the same tid */
314 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
315 WLAN_STATUS_UNSPECIFIED_QOS,
316 false);
317 }
318
319 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) {
320 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
321 ht_dbg(sta->sdata,
322 "Rx A-MPDU request on %pM tid %d result %d\n",
323 sta->sta.addr, tid, ret);
324 if (!ret)
325 status = WLAN_STATUS_SUCCESS;
326 goto end;
327 }
328
329 /* prepare A-MPDU MLME for Rx aggregation */
330 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL);
331 if (!tid_agg_rx)
332 goto end;
333
334 spin_lock_init(&tid_agg_rx->reorder_lock);
335
336 /* rx timer */
337 tid_agg_rx->session_timer.function = sta_rx_agg_session_timer_expired;
338 tid_agg_rx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid];
339 init_timer_deferrable(&tid_agg_rx->session_timer);
340
341 /* rx reorder timer */
342 tid_agg_rx->reorder_timer.function = sta_rx_agg_reorder_timer_expired;
343 tid_agg_rx->reorder_timer.data = (unsigned long)&sta->timer_to_tid[tid];
344 init_timer(&tid_agg_rx->reorder_timer);
345
346 /* prepare reordering buffer */
347 tid_agg_rx->reorder_buf =
348 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
349 tid_agg_rx->reorder_time =
350 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
351 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
352 kfree(tid_agg_rx->reorder_buf);
353 kfree(tid_agg_rx->reorder_time);
354 kfree(tid_agg_rx);
355 goto end;
356 }
357
358 for (i = 0; i < buf_size; i++)
359 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
360
361 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
362 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
363 sta->sta.addr, tid, ret);
364 if (ret) {
365 kfree(tid_agg_rx->reorder_buf);
366 kfree(tid_agg_rx->reorder_time);
367 kfree(tid_agg_rx);
368 goto end;
369 }
370
371 /* update data */
372 tid_agg_rx->dialog_token = dialog_token;
373 tid_agg_rx->ssn = start_seq_num;
374 tid_agg_rx->head_seq_num = start_seq_num;
375 tid_agg_rx->buf_size = buf_size;
376 tid_agg_rx->timeout = timeout;
377 tid_agg_rx->stored_mpdu_num = 0;
378 tid_agg_rx->auto_seq = auto_seq;
379 tid_agg_rx->reorder_buf_filtered = 0;
380 status = WLAN_STATUS_SUCCESS;
381
382 /* activate it for RX */
383 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
384
385 if (timeout) {
386 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
387 tid_agg_rx->last_rx = jiffies;
388 }
389
390end:
391 if (status == WLAN_STATUS_SUCCESS)
392 __set_bit(tid, sta->ampdu_mlme.agg_session_valid);
393 mutex_unlock(&sta->ampdu_mlme.mtx);
394
395end_no_lock:
396 if (tx)
397 ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
398 dialog_token, status, 1, buf_size,
399 timeout);
400}
401
402void ieee80211_process_addba_request(struct ieee80211_local *local,
403 struct sta_info *sta,
404 struct ieee80211_mgmt *mgmt,
405 size_t len)
406{
407 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
408 u8 dialog_token;
409
410 /* extract session parameters from addba request frame */
411 dialog_token = mgmt->u.action.u.addba_req.dialog_token;
412 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
413 start_seq_num =
414 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
415
416 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
417 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
418 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
419 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
420
421 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
422 start_seq_num, ba_policy, tid,
423 buf_size, true, false);
424}
425
426void ieee80211_start_rx_ba_session_offl(struct ieee80211_vif *vif,
427 const u8 *addr, u16 tid)
428{
429 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
430 struct ieee80211_local *local = sdata->local;
431 struct ieee80211_rx_agg *rx_agg;
432 struct sk_buff *skb = dev_alloc_skb(0);
433
434 if (unlikely(!skb))
435 return;
436
437 rx_agg = (struct ieee80211_rx_agg *) &skb->cb;
438 memcpy(&rx_agg->addr, addr, ETH_ALEN);
439 rx_agg->tid = tid;
440
441 skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_START;
442 skb_queue_tail(&sdata->skb_queue, skb);
443 ieee80211_queue_work(&local->hw, &sdata->work);
444}
445EXPORT_SYMBOL(ieee80211_start_rx_ba_session_offl);
446
447void ieee80211_stop_rx_ba_session_offl(struct ieee80211_vif *vif,
448 const u8 *addr, u16 tid)
449{
450 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
451 struct ieee80211_local *local = sdata->local;
452 struct ieee80211_rx_agg *rx_agg;
453 struct sk_buff *skb = dev_alloc_skb(0);
454
455 if (unlikely(!skb))
456 return;
457
458 rx_agg = (struct ieee80211_rx_agg *) &skb->cb;
459 memcpy(&rx_agg->addr, addr, ETH_ALEN);
460 rx_agg->tid = tid;
461
462 skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_STOP;
463 skb_queue_tail(&sdata->skb_queue, skb);
464 ieee80211_queue_work(&local->hw, &sdata->work);
465}
466EXPORT_SYMBOL(ieee80211_stop_rx_ba_session_offl);