1 // SPDX-License-Identifier: GPL-2.0-only
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) 2018-2021 Intel Corporation
16 * DOC: RX A-MPDU aggregation
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.
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.
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.
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
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"
45 static void ieee80211_free_tid_rx(struct rcu_head *h)
47 struct tid_ampdu_rx *tid_rx =
48 container_of(h, struct tid_ampdu_rx, rcu_head);
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);
58 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
59 u16 initiator, u16 reason, bool tx)
61 struct ieee80211_local *local = sta->local;
62 struct tid_ampdu_rx *tid_rx;
63 struct ieee80211_ampdu_params params = {
65 .action = IEEE80211_AMPDU_RX_STOP,
72 lockdep_assert_held(&sta->ampdu_mlme.mtx);
74 tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid],
75 lockdep_is_held(&sta->ampdu_mlme.mtx));
77 if (!test_bit(tid, sta->ampdu_mlme.agg_session_valid))
80 RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL);
81 __clear_bit(tid, sta->ampdu_mlme.agg_session_valid);
84 "Rx BA session stop requested for %pM tid %u %s reason: %d\n",
86 initiator == WLAN_BACK_RECIPIENT ? "recipient" : "initiator",
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",
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);
100 * return here in case tid_rx is not assigned - which will happen if
101 * IEEE80211_HW_SUPPORTS_REORDERING_BUFFER is set.
106 del_timer_sync(&tid_rx->session_timer);
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);
114 call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx);
117 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
118 u16 initiator, u16 reason, bool tx)
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);
125 void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap,
128 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
129 struct sta_info *sta;
133 sta = sta_info_get_bss(sdata, addr);
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);
143 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
146 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session);
149 * After accepting the AddBA Request we activated a timer,
150 * resetting it after each frame that arrives from the originator.
152 static void sta_rx_agg_session_timer_expired(struct timer_list *t)
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;
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);
165 ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n",
168 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
169 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
172 static void sta_rx_agg_reorder_timer_expired(struct timer_list *t)
174 struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, reorder_timer);
177 ieee80211_release_reorder_timeout(tid_rx->sta, tid_rx->tid);
181 static void ieee80211_add_addbaext(struct ieee80211_sub_if_data *sdata,
183 const struct ieee80211_addba_ext_ie *req)
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;
191 sband = ieee80211_get_sband(sdata);
194 he_cap = ieee80211_get_he_iftype_cap(sband,
195 ieee80211_vif_type_p2p(&sdata->vif));
199 pos = skb_put_zero(skb, 2 + sizeof(struct ieee80211_addba_ext_ie));
200 *pos++ = WLAN_EID_ADDBA_EXT;
201 *pos++ = sizeof(struct ieee80211_addba_ext_ie);
202 resp = (struct ieee80211_addba_ext_ie *)pos;
203 resp->data = req->data & IEEE80211_ADDBA_EXT_NO_FRAG;
205 frag_level = u32_get_bits(req->data,
206 IEEE80211_ADDBA_EXT_FRAG_LEVEL_MASK);
207 cap_frag_level = u32_get_bits(he_cap->he_cap_elem.mac_cap_info[0],
208 IEEE80211_HE_MAC_CAP0_DYNAMIC_FRAG_MASK);
209 if (frag_level > cap_frag_level)
210 frag_level = cap_frag_level;
211 resp->data |= u8_encode_bits(frag_level,
212 IEEE80211_ADDBA_EXT_FRAG_LEVEL_MASK);
215 static void ieee80211_send_addba_resp(struct sta_info *sta, u8 *da, u16 tid,
216 u8 dialog_token, u16 status, u16 policy,
217 u16 buf_size, u16 timeout,
218 const struct ieee80211_addba_ext_ie *addbaext)
220 struct ieee80211_sub_if_data *sdata = sta->sdata;
221 struct ieee80211_local *local = sdata->local;
223 struct ieee80211_mgmt *mgmt;
224 bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU);
227 skb = dev_alloc_skb(sizeof(*mgmt) +
228 2 + sizeof(struct ieee80211_addba_ext_ie) +
229 local->hw.extra_tx_headroom);
233 skb_reserve(skb, local->hw.extra_tx_headroom);
234 mgmt = skb_put_zero(skb, 24);
235 memcpy(mgmt->da, da, ETH_ALEN);
236 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
237 if (sdata->vif.type == NL80211_IFTYPE_AP ||
238 sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
239 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
240 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
241 else if (sdata->vif.type == NL80211_IFTYPE_STATION)
242 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
243 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
244 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
246 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
247 IEEE80211_STYPE_ACTION);
249 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
250 mgmt->u.action.category = WLAN_CATEGORY_BACK;
251 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
252 mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
254 capab = u16_encode_bits(amsdu, IEEE80211_ADDBA_PARAM_AMSDU_MASK);
255 capab |= u16_encode_bits(policy, IEEE80211_ADDBA_PARAM_POLICY_MASK);
256 capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
257 capab |= u16_encode_bits(buf_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
259 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
260 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
261 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
263 if (sta->sta.he_cap.has_he && addbaext)
264 ieee80211_add_addbaext(sdata, skb, addbaext);
266 ieee80211_tx_skb(sdata, skb);
269 void ___ieee80211_start_rx_ba_session(struct sta_info *sta,
270 u8 dialog_token, u16 timeout,
271 u16 start_seq_num, u16 ba_policy, u16 tid,
272 u16 buf_size, bool tx, bool auto_seq,
273 const struct ieee80211_addba_ext_ie *addbaext)
275 struct ieee80211_local *local = sta->sdata->local;
276 struct tid_ampdu_rx *tid_agg_rx;
277 struct ieee80211_ampdu_params params = {
279 .action = IEEE80211_AMPDU_RX_START,
283 .ssn = start_seq_num,
285 int i, ret = -EOPNOTSUPP;
286 u16 status = WLAN_STATUS_REQUEST_DECLINED;
289 if (tid >= IEEE80211_FIRST_TSPEC_TSID) {
291 "STA %pM requests BA session on unsupported tid %d\n",
296 if (!sta->sta.ht_cap.ht_supported &&
297 sta->sdata->vif.bss_conf.chandef.chan->band != NL80211_BAND_6GHZ) {
299 "STA %pM erroneously requests BA session on tid %d w/o QoS\n",
301 /* send a response anyway, it's an error case if we get here */
305 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
307 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
312 if (sta->sta.he_cap.has_he)
313 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HE;
315 max_buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
317 /* sanity check for incoming parameters:
318 * check if configuration can support the BA policy
319 * and if buffer size does not exceeds max value */
320 /* XXX: check own ht delayed BA capability?? */
321 if (((ba_policy != 1) &&
322 (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
323 (buf_size > max_buf_size)) {
324 status = WLAN_STATUS_INVALID_QOS_PARAM;
325 ht_dbg_ratelimited(sta->sdata,
326 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
327 sta->sta.addr, tid, ba_policy, buf_size);
330 /* determine default buffer size */
332 buf_size = max_buf_size;
334 /* make sure the size doesn't exceed the maximum supported by the hw */
335 if (buf_size > sta->sta.max_rx_aggregation_subframes)
336 buf_size = sta->sta.max_rx_aggregation_subframes;
337 params.buf_size = buf_size;
339 ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
340 buf_size, sta->sta.addr);
342 /* examine state machine */
343 lockdep_assert_held(&sta->ampdu_mlme.mtx);
345 if (test_bit(tid, sta->ampdu_mlme.agg_session_valid)) {
346 if (sta->ampdu_mlme.tid_rx_token[tid] == dialog_token) {
347 struct tid_ampdu_rx *tid_rx;
349 ht_dbg_ratelimited(sta->sdata,
350 "updated AddBA Req from %pM on tid %u\n",
352 /* We have no API to update the timeout value in the
353 * driver so reject the timeout update if the timeout
354 * changed. If it did not change, i.e., no real update,
355 * just reply with success.
358 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
359 if (tid_rx && tid_rx->timeout == timeout)
360 status = WLAN_STATUS_SUCCESS;
362 status = WLAN_STATUS_REQUEST_DECLINED;
367 ht_dbg_ratelimited(sta->sdata,
368 "unexpected AddBA Req from %pM on tid %u\n",
371 /* delete existing Rx BA session on the same tid */
372 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
373 WLAN_STATUS_UNSPECIFIED_QOS,
377 if (ieee80211_hw_check(&local->hw, SUPPORTS_REORDERING_BUFFER)) {
378 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
380 "Rx A-MPDU request on %pM tid %d result %d\n",
381 sta->sta.addr, tid, ret);
383 status = WLAN_STATUS_SUCCESS;
387 /* prepare A-MPDU MLME for Rx aggregation */
388 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL);
392 spin_lock_init(&tid_agg_rx->reorder_lock);
395 timer_setup(&tid_agg_rx->session_timer,
396 sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE);
398 /* rx reorder timer */
399 timer_setup(&tid_agg_rx->reorder_timer,
400 sta_rx_agg_reorder_timer_expired, 0);
402 /* prepare reordering buffer */
403 tid_agg_rx->reorder_buf =
404 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
405 tid_agg_rx->reorder_time =
406 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
407 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
408 kfree(tid_agg_rx->reorder_buf);
409 kfree(tid_agg_rx->reorder_time);
414 for (i = 0; i < buf_size; i++)
415 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
417 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
418 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
419 sta->sta.addr, tid, ret);
421 kfree(tid_agg_rx->reorder_buf);
422 kfree(tid_agg_rx->reorder_time);
428 tid_agg_rx->ssn = start_seq_num;
429 tid_agg_rx->head_seq_num = start_seq_num;
430 tid_agg_rx->buf_size = buf_size;
431 tid_agg_rx->timeout = timeout;
432 tid_agg_rx->stored_mpdu_num = 0;
433 tid_agg_rx->auto_seq = auto_seq;
434 tid_agg_rx->started = false;
435 tid_agg_rx->reorder_buf_filtered = 0;
436 tid_agg_rx->tid = tid;
437 tid_agg_rx->sta = sta;
438 status = WLAN_STATUS_SUCCESS;
440 /* activate it for RX */
441 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
444 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
445 tid_agg_rx->last_rx = jiffies;
449 if (status == WLAN_STATUS_SUCCESS) {
450 __set_bit(tid, sta->ampdu_mlme.agg_session_valid);
451 __clear_bit(tid, sta->ampdu_mlme.unexpected_agg);
452 sta->ampdu_mlme.tid_rx_token[tid] = dialog_token;
456 ieee80211_send_addba_resp(sta, sta->sta.addr, tid,
457 dialog_token, status, 1, buf_size,
461 static void __ieee80211_start_rx_ba_session(struct sta_info *sta,
462 u8 dialog_token, u16 timeout,
463 u16 start_seq_num, u16 ba_policy,
464 u16 tid, u16 buf_size, bool tx,
466 const struct ieee80211_addba_ext_ie *addbaext)
468 mutex_lock(&sta->ampdu_mlme.mtx);
469 ___ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
470 start_seq_num, ba_policy, tid,
471 buf_size, tx, auto_seq, addbaext);
472 mutex_unlock(&sta->ampdu_mlme.mtx);
475 void ieee80211_process_addba_request(struct ieee80211_local *local,
476 struct sta_info *sta,
477 struct ieee80211_mgmt *mgmt,
480 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
481 struct ieee802_11_elems *elems = NULL;
485 /* extract session parameters from addba request frame */
486 dialog_token = mgmt->u.action.u.addba_req.dialog_token;
487 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
489 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
491 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
492 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
493 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
494 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
496 ies_len = len - offsetof(struct ieee80211_mgmt,
497 u.action.u.addba_req.variable);
499 elems = ieee802_11_parse_elems(mgmt->u.action.u.addba_req.variable,
500 ies_len, true, mgmt->bssid, NULL);
501 if (!elems || elems->parse_error)
505 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
506 start_seq_num, ba_policy, tid,
507 buf_size, true, false,
508 elems ? elems->addba_ext_ie : NULL);
513 void ieee80211_manage_rx_ba_offl(struct ieee80211_vif *vif,
514 const u8 *addr, unsigned int tid)
516 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
517 struct ieee80211_local *local = sdata->local;
518 struct sta_info *sta;
521 sta = sta_info_get_bss(sdata, addr);
525 set_bit(tid, sta->ampdu_mlme.tid_rx_manage_offl);
526 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
530 EXPORT_SYMBOL(ieee80211_manage_rx_ba_offl);
532 void ieee80211_rx_ba_timer_expired(struct ieee80211_vif *vif,
533 const u8 *addr, unsigned int tid)
535 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
536 struct ieee80211_local *local = sdata->local;
537 struct sta_info *sta;
540 sta = sta_info_get_bss(sdata, addr);
544 set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
545 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
550 EXPORT_SYMBOL(ieee80211_rx_ba_timer_expired);