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
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.
18 * DOC: RX A-MPDU aggregation
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.
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.
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.
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
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"
47 static void ieee80211_free_tid_rx(struct rcu_head *h)
49 struct tid_ampdu_rx *tid_rx =
50 container_of(h, struct tid_ampdu_rx, rcu_head);
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);
60 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
61 u16 initiator, u16 reason, bool tx)
63 struct ieee80211_local *local = sta->local;
64 struct tid_ampdu_rx *tid_rx;
65 struct ieee80211_ampdu_params params = {
67 .action = IEEE80211_AMPDU_RX_STOP,
74 lockdep_assert_held(&sta->ampdu_mlme.mtx);
76 tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid],
77 lockdep_is_held(&sta->ampdu_mlme.mtx));
82 RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL);
85 "Rx BA session stop requested for %pM tid %u %s reason: %d\n",
87 initiator == WLAN_BACK_RECIPIENT ? "recipient" : "inititator",
90 if (drv_ampdu_action(local, sta->sdata, ¶ms))
91 sdata_info(sta->sdata,
92 "HW problem - can not stop rx aggregation for %pM tid %d\n",
95 /* check if this is a self generated aggregation halt */
96 if (initiator == WLAN_BACK_RECIPIENT && tx)
97 ieee80211_send_delba(sta->sdata, sta->sta.addr,
98 tid, WLAN_BACK_RECIPIENT, reason);
100 del_timer_sync(&tid_rx->session_timer);
102 /* make sure ieee80211_sta_reorder_release() doesn't re-arm the timer */
103 spin_lock_bh(&tid_rx->reorder_lock);
104 tid_rx->removed = true;
105 spin_unlock_bh(&tid_rx->reorder_lock);
106 del_timer_sync(&tid_rx->reorder_timer);
108 call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx);
111 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
112 u16 initiator, u16 reason, bool tx)
114 mutex_lock(&sta->ampdu_mlme.mtx);
115 ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx);
116 mutex_unlock(&sta->ampdu_mlme.mtx);
119 void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap,
122 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
123 struct sta_info *sta;
127 sta = sta_info_get_bss(sdata, addr);
133 for (i = 0; i < IEEE80211_NUM_TIDS; i++)
134 if (ba_rx_bitmap & BIT(i))
135 set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested);
137 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
140 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session);
143 * After accepting the AddBA Request we activated a timer,
144 * resetting it after each frame that arrives from the originator.
146 static void sta_rx_agg_session_timer_expired(unsigned long data)
148 /* not an elegant detour, but there is no choice as the timer passes
149 * only one argument, and various sta_info are needed here, so init
150 * flow in sta_info_create gives the TID as data, while the timer_to_id
151 * array gives the sta through container_of */
152 u8 *ptid = (u8 *)data;
153 u8 *timer_to_id = ptid - *ptid;
154 struct sta_info *sta = container_of(timer_to_id, struct sta_info,
156 struct tid_ampdu_rx *tid_rx;
157 unsigned long timeout;
160 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[*ptid]);
166 timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout);
167 if (time_is_after_jiffies(timeout)) {
168 mod_timer(&tid_rx->session_timer, timeout);
174 ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n",
175 sta->sta.addr, (u16)*ptid);
177 set_bit(*ptid, sta->ampdu_mlme.tid_rx_timer_expired);
178 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
181 static void sta_rx_agg_reorder_timer_expired(unsigned long data)
183 u8 *ptid = (u8 *)data;
184 u8 *timer_to_id = ptid - *ptid;
185 struct sta_info *sta = container_of(timer_to_id, struct sta_info,
189 ieee80211_release_reorder_timeout(sta, *ptid);
193 static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
194 u8 dialog_token, u16 status, u16 policy,
195 u16 buf_size, u16 timeout)
197 struct ieee80211_local *local = sdata->local;
199 struct ieee80211_mgmt *mgmt;
200 bool amsdu = ieee80211_hw_check(&local->hw, SUPPORTS_AMSDU_IN_AMPDU);
203 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
207 skb_reserve(skb, local->hw.extra_tx_headroom);
208 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
210 memcpy(mgmt->da, da, ETH_ALEN);
211 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
212 if (sdata->vif.type == NL80211_IFTYPE_AP ||
213 sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
214 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
215 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
216 else if (sdata->vif.type == NL80211_IFTYPE_STATION)
217 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
218 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
219 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
221 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
222 IEEE80211_STYPE_ACTION);
224 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
225 mgmt->u.action.category = WLAN_CATEGORY_BACK;
226 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
227 mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
229 capab = (u16)(amsdu << 0); /* bit 0 A-MSDU support */
230 capab |= (u16)(policy << 1); /* bit 1 aggregation policy */
231 capab |= (u16)(tid << 2); /* bit 5:2 TID number */
232 capab |= (u16)(buf_size << 6); /* bit 15:6 max size of aggregation */
234 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
235 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
236 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
238 ieee80211_tx_skb(sdata, skb);
241 void __ieee80211_start_rx_ba_session(struct sta_info *sta,
242 u8 dialog_token, u16 timeout,
243 u16 start_seq_num, u16 ba_policy, u16 tid,
244 u16 buf_size, bool tx, bool auto_seq)
246 struct ieee80211_local *local = sta->sdata->local;
247 struct tid_ampdu_rx *tid_agg_rx;
248 struct ieee80211_ampdu_params params = {
250 .action = IEEE80211_AMPDU_RX_START,
254 .ssn = start_seq_num,
257 int i, ret = -EOPNOTSUPP;
258 u16 status = WLAN_STATUS_REQUEST_DECLINED;
260 if (!sta->sta.ht_cap.ht_supported) {
262 "STA %pM erroneously requests BA session on tid %d w/o QoS\n",
264 /* send a response anyway, it's an error case if we get here */
268 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
270 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
275 /* sanity check for incoming parameters:
276 * check if configuration can support the BA policy
277 * and if buffer size does not exceeds max value */
278 /* XXX: check own ht delayed BA capability?? */
279 if (((ba_policy != 1) &&
280 (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
281 (buf_size > IEEE80211_MAX_AMPDU_BUF)) {
282 status = WLAN_STATUS_INVALID_QOS_PARAM;
283 ht_dbg_ratelimited(sta->sdata,
284 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
285 sta->sta.addr, tid, ba_policy, buf_size);
288 /* determine default buffer size */
290 buf_size = IEEE80211_MAX_AMPDU_BUF;
292 /* make sure the size doesn't exceed the maximum supported by the hw */
293 if (buf_size > sta->sta.max_rx_aggregation_subframes)
294 buf_size = sta->sta.max_rx_aggregation_subframes;
295 params.buf_size = buf_size;
297 ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
298 buf_size, sta->sta.addr);
300 /* examine state machine */
301 mutex_lock(&sta->ampdu_mlme.mtx);
303 if (sta->ampdu_mlme.tid_rx[tid]) {
304 ht_dbg_ratelimited(sta->sdata,
305 "unexpected AddBA Req from %pM on tid %u\n",
308 /* delete existing Rx BA session on the same tid */
309 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
310 WLAN_STATUS_UNSPECIFIED_QOS,
314 /* prepare A-MPDU MLME for Rx aggregation */
315 tid_agg_rx = kzalloc(sizeof(*tid_agg_rx), GFP_KERNEL);
319 spin_lock_init(&tid_agg_rx->reorder_lock);
322 tid_agg_rx->session_timer.function = sta_rx_agg_session_timer_expired;
323 tid_agg_rx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid];
324 init_timer_deferrable(&tid_agg_rx->session_timer);
326 /* rx reorder timer */
327 tid_agg_rx->reorder_timer.function = sta_rx_agg_reorder_timer_expired;
328 tid_agg_rx->reorder_timer.data = (unsigned long)&sta->timer_to_tid[tid];
329 init_timer(&tid_agg_rx->reorder_timer);
331 /* prepare reordering buffer */
332 tid_agg_rx->reorder_buf =
333 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
334 tid_agg_rx->reorder_time =
335 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
336 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
337 kfree(tid_agg_rx->reorder_buf);
338 kfree(tid_agg_rx->reorder_time);
343 for (i = 0; i < buf_size; i++)
344 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
346 ret = drv_ampdu_action(local, sta->sdata, ¶ms);
347 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
348 sta->sta.addr, tid, ret);
350 kfree(tid_agg_rx->reorder_buf);
351 kfree(tid_agg_rx->reorder_time);
357 tid_agg_rx->dialog_token = dialog_token;
358 tid_agg_rx->ssn = start_seq_num;
359 tid_agg_rx->head_seq_num = start_seq_num;
360 tid_agg_rx->buf_size = buf_size;
361 tid_agg_rx->timeout = timeout;
362 tid_agg_rx->stored_mpdu_num = 0;
363 tid_agg_rx->auto_seq = auto_seq;
364 status = WLAN_STATUS_SUCCESS;
366 /* activate it for RX */
367 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
370 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
371 tid_agg_rx->last_rx = jiffies;
375 mutex_unlock(&sta->ampdu_mlme.mtx);
379 ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
380 dialog_token, status, 1, buf_size,
384 void ieee80211_process_addba_request(struct ieee80211_local *local,
385 struct sta_info *sta,
386 struct ieee80211_mgmt *mgmt,
389 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
392 /* extract session parameters from addba request frame */
393 dialog_token = mgmt->u.action.u.addba_req.dialog_token;
394 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
396 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
398 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
399 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
400 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
401 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
403 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
404 start_seq_num, ba_policy, tid,
405 buf_size, true, false);
408 void ieee80211_start_rx_ba_session_offl(struct ieee80211_vif *vif,
409 const u8 *addr, u16 tid)
411 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
412 struct ieee80211_local *local = sdata->local;
413 struct ieee80211_rx_agg *rx_agg;
414 struct sk_buff *skb = dev_alloc_skb(0);
419 rx_agg = (struct ieee80211_rx_agg *) &skb->cb;
420 memcpy(&rx_agg->addr, addr, ETH_ALEN);
423 skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_START;
424 skb_queue_tail(&sdata->skb_queue, skb);
425 ieee80211_queue_work(&local->hw, &sdata->work);
427 EXPORT_SYMBOL(ieee80211_start_rx_ba_session_offl);
429 void ieee80211_stop_rx_ba_session_offl(struct ieee80211_vif *vif,
430 const u8 *addr, u16 tid)
432 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
433 struct ieee80211_local *local = sdata->local;
434 struct ieee80211_rx_agg *rx_agg;
435 struct sk_buff *skb = dev_alloc_skb(0);
440 rx_agg = (struct ieee80211_rx_agg *) &skb->cb;
441 memcpy(&rx_agg->addr, addr, ETH_ALEN);
444 skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_STOP;
445 skb_queue_tail(&sdata->skb_queue, skb);
446 ieee80211_queue_work(&local->hw, &sdata->work);
448 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session_offl);