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
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License version 2 as
13 * published by the Free Software Foundation.
17 * DOC: RX A-MPDU aggregation
19 * Aggregation on the RX side requires only implementing the
20 * @ampdu_action callback that is invoked to start/stop any
21 * block-ack sessions for RX aggregation.
23 * When RX aggregation is started by the peer, the driver is
24 * notified via @ampdu_action function, with the
25 * %IEEE80211_AMPDU_RX_START action, and may reject the request
26 * in which case a negative response is sent to the peer, if it
27 * accepts it a positive response is sent.
29 * While the session is active, the device/driver are required
30 * to de-aggregate frames and pass them up one by one to mac80211,
31 * which will handle the reorder buffer.
33 * When the aggregation session is stopped again by the peer or
34 * ourselves, the driver's @ampdu_action function will be called
35 * with the action %IEEE80211_AMPDU_RX_STOP. In this case, the
39 #include <linux/ieee80211.h>
40 #include <linux/slab.h>
41 #include <linux/export.h>
42 #include <net/mac80211.h>
43 #include "ieee80211_i.h"
44 #include "driver-ops.h"
46 static void ieee80211_free_tid_rx(struct rcu_head *h)
48 struct tid_ampdu_rx *tid_rx =
49 container_of(h, struct tid_ampdu_rx, rcu_head);
52 del_timer_sync(&tid_rx->reorder_timer);
54 for (i = 0; i < tid_rx->buf_size; i++)
55 __skb_queue_purge(&tid_rx->reorder_buf[i]);
56 kfree(tid_rx->reorder_buf);
57 kfree(tid_rx->reorder_time);
61 void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
62 u16 initiator, u16 reason, bool tx)
64 struct ieee80211_local *local = sta->local;
65 struct tid_ampdu_rx *tid_rx;
67 lockdep_assert_held(&sta->ampdu_mlme.mtx);
69 tid_rx = rcu_dereference_protected(sta->ampdu_mlme.tid_rx[tid],
70 lockdep_is_held(&sta->ampdu_mlme.mtx));
75 RCU_INIT_POINTER(sta->ampdu_mlme.tid_rx[tid], NULL);
78 "Rx BA session stop requested for %pM tid %u %s reason: %d\n",
80 initiator == WLAN_BACK_RECIPIENT ? "recipient" : "inititator",
83 if (drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_STOP,
84 &sta->sta, tid, NULL, 0))
85 sdata_info(sta->sdata,
86 "HW problem - can not stop rx aggregation for %pM tid %d\n",
89 /* check if this is a self generated aggregation halt */
90 if (initiator == WLAN_BACK_RECIPIENT && tx)
91 ieee80211_send_delba(sta->sdata, sta->sta.addr,
92 tid, WLAN_BACK_RECIPIENT, reason);
94 del_timer_sync(&tid_rx->session_timer);
96 call_rcu(&tid_rx->rcu_head, ieee80211_free_tid_rx);
99 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
100 u16 initiator, u16 reason, bool tx)
102 mutex_lock(&sta->ampdu_mlme.mtx);
103 ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, tx);
104 mutex_unlock(&sta->ampdu_mlme.mtx);
107 void ieee80211_stop_rx_ba_session(struct ieee80211_vif *vif, u16 ba_rx_bitmap,
110 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
111 struct sta_info *sta;
115 sta = sta_info_get_bss(sdata, addr);
121 for (i = 0; i < IEEE80211_NUM_TIDS; i++)
122 if (ba_rx_bitmap & BIT(i))
123 set_bit(i, sta->ampdu_mlme.tid_rx_stop_requested);
125 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
128 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session);
131 * After accepting the AddBA Request we activated a timer,
132 * resetting it after each frame that arrives from the originator.
134 static void sta_rx_agg_session_timer_expired(unsigned long data)
136 /* not an elegant detour, but there is no choice as the timer passes
137 * only one argument, and various sta_info are needed here, so init
138 * flow in sta_info_create gives the TID as data, while the timer_to_id
139 * array gives the sta through container_of */
140 u8 *ptid = (u8 *)data;
141 u8 *timer_to_id = ptid - *ptid;
142 struct sta_info *sta = container_of(timer_to_id, struct sta_info,
144 struct tid_ampdu_rx *tid_rx;
145 unsigned long timeout;
148 tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[*ptid]);
154 timeout = tid_rx->last_rx + TU_TO_JIFFIES(tid_rx->timeout);
155 if (time_is_after_jiffies(timeout)) {
156 mod_timer(&tid_rx->session_timer, timeout);
162 ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n",
163 sta->sta.addr, (u16)*ptid);
165 set_bit(*ptid, sta->ampdu_mlme.tid_rx_timer_expired);
166 ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
169 static void sta_rx_agg_reorder_timer_expired(unsigned long data)
171 u8 *ptid = (u8 *)data;
172 u8 *timer_to_id = ptid - *ptid;
173 struct sta_info *sta = container_of(timer_to_id, struct sta_info,
177 ieee80211_release_reorder_timeout(sta, *ptid);
181 static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
182 u8 dialog_token, u16 status, u16 policy,
183 u16 buf_size, u16 timeout)
185 struct ieee80211_local *local = sdata->local;
187 struct ieee80211_mgmt *mgmt;
190 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
194 skb_reserve(skb, local->hw.extra_tx_headroom);
195 mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
197 memcpy(mgmt->da, da, ETH_ALEN);
198 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
199 if (sdata->vif.type == NL80211_IFTYPE_AP ||
200 sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
201 sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
202 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
203 else if (sdata->vif.type == NL80211_IFTYPE_STATION)
204 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
205 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
206 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
208 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
209 IEEE80211_STYPE_ACTION);
211 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
212 mgmt->u.action.category = WLAN_CATEGORY_BACK;
213 mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
214 mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
216 capab = (u16)(policy << 1); /* bit 1 aggregation policy */
217 capab |= (u16)(tid << 2); /* bit 5:2 TID number */
218 capab |= (u16)(buf_size << 6); /* bit 15:6 max size of aggregation */
220 mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
221 mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
222 mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
224 ieee80211_tx_skb(sdata, skb);
227 void __ieee80211_start_rx_ba_session(struct sta_info *sta,
228 u8 dialog_token, u16 timeout,
229 u16 start_seq_num, u16 ba_policy, u16 tid,
230 u16 buf_size, bool tx, bool auto_seq)
232 struct ieee80211_local *local = sta->sdata->local;
233 struct tid_ampdu_rx *tid_agg_rx;
234 int i, ret = -EOPNOTSUPP;
235 u16 status = WLAN_STATUS_REQUEST_DECLINED;
237 if (!sta->sta.ht_cap.ht_supported) {
239 "STA %pM erroneously requests BA session on tid %d w/o QoS\n",
241 /* send a response anyway, it's an error case if we get here */
245 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
247 "Suspend in progress - Denying ADDBA request (%pM tid %d)\n",
252 /* sanity check for incoming parameters:
253 * check if configuration can support the BA policy
254 * and if buffer size does not exceeds max value */
255 /* XXX: check own ht delayed BA capability?? */
256 if (((ba_policy != 1) &&
257 (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
258 (buf_size > IEEE80211_MAX_AMPDU_BUF)) {
259 status = WLAN_STATUS_INVALID_QOS_PARAM;
260 ht_dbg_ratelimited(sta->sdata,
261 "AddBA Req with bad params from %pM on tid %u. policy %d, buffer size %d\n",
262 sta->sta.addr, tid, ba_policy, buf_size);
265 /* determine default buffer size */
267 buf_size = IEEE80211_MAX_AMPDU_BUF;
269 /* make sure the size doesn't exceed the maximum supported by the hw */
270 if (buf_size > local->hw.max_rx_aggregation_subframes)
271 buf_size = local->hw.max_rx_aggregation_subframes;
273 /* examine state machine */
274 mutex_lock(&sta->ampdu_mlme.mtx);
276 if (sta->ampdu_mlme.tid_rx[tid]) {
277 ht_dbg_ratelimited(sta->sdata,
278 "unexpected AddBA Req from %pM on tid %u\n",
281 /* delete existing Rx BA session on the same tid */
282 ___ieee80211_stop_rx_ba_session(sta, tid, WLAN_BACK_RECIPIENT,
283 WLAN_STATUS_UNSPECIFIED_QOS,
287 /* prepare A-MPDU MLME for Rx aggregation */
288 tid_agg_rx = kmalloc(sizeof(struct tid_ampdu_rx), GFP_KERNEL);
292 spin_lock_init(&tid_agg_rx->reorder_lock);
295 tid_agg_rx->session_timer.function = sta_rx_agg_session_timer_expired;
296 tid_agg_rx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid];
297 init_timer_deferrable(&tid_agg_rx->session_timer);
299 /* rx reorder timer */
300 tid_agg_rx->reorder_timer.function = sta_rx_agg_reorder_timer_expired;
301 tid_agg_rx->reorder_timer.data = (unsigned long)&sta->timer_to_tid[tid];
302 init_timer(&tid_agg_rx->reorder_timer);
304 /* prepare reordering buffer */
305 tid_agg_rx->reorder_buf =
306 kcalloc(buf_size, sizeof(struct sk_buff_head), GFP_KERNEL);
307 tid_agg_rx->reorder_time =
308 kcalloc(buf_size, sizeof(unsigned long), GFP_KERNEL);
309 if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
310 kfree(tid_agg_rx->reorder_buf);
311 kfree(tid_agg_rx->reorder_time);
316 for (i = 0; i < buf_size; i++)
317 __skb_queue_head_init(&tid_agg_rx->reorder_buf[i]);
319 ret = drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_START,
320 &sta->sta, tid, &start_seq_num, 0);
321 ht_dbg(sta->sdata, "Rx A-MPDU request on %pM tid %d result %d\n",
322 sta->sta.addr, tid, ret);
324 kfree(tid_agg_rx->reorder_buf);
325 kfree(tid_agg_rx->reorder_time);
331 tid_agg_rx->dialog_token = dialog_token;
332 tid_agg_rx->ssn = start_seq_num;
333 tid_agg_rx->head_seq_num = start_seq_num;
334 tid_agg_rx->buf_size = buf_size;
335 tid_agg_rx->timeout = timeout;
336 tid_agg_rx->stored_mpdu_num = 0;
337 tid_agg_rx->auto_seq = auto_seq;
338 status = WLAN_STATUS_SUCCESS;
340 /* activate it for RX */
341 rcu_assign_pointer(sta->ampdu_mlme.tid_rx[tid], tid_agg_rx);
344 mod_timer(&tid_agg_rx->session_timer, TU_TO_EXP_TIME(timeout));
345 tid_agg_rx->last_rx = jiffies;
349 mutex_unlock(&sta->ampdu_mlme.mtx);
353 ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
354 dialog_token, status, 1, buf_size,
358 void ieee80211_process_addba_request(struct ieee80211_local *local,
359 struct sta_info *sta,
360 struct ieee80211_mgmt *mgmt,
363 u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num;
366 /* extract session parameters from addba request frame */
367 dialog_token = mgmt->u.action.u.addba_req.dialog_token;
368 timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
370 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
372 capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
373 ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
374 tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
375 buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
377 __ieee80211_start_rx_ba_session(sta, dialog_token, timeout,
378 start_seq_num, ba_policy, tid,
379 buf_size, true, false);
382 void ieee80211_start_rx_ba_session_offl(struct ieee80211_vif *vif,
383 const u8 *addr, u16 tid)
385 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
386 struct ieee80211_local *local = sdata->local;
387 struct ieee80211_rx_agg *rx_agg;
388 struct sk_buff *skb = dev_alloc_skb(0);
393 rx_agg = (struct ieee80211_rx_agg *) &skb->cb;
394 memcpy(&rx_agg->addr, addr, ETH_ALEN);
397 skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_START;
398 skb_queue_tail(&sdata->skb_queue, skb);
399 ieee80211_queue_work(&local->hw, &sdata->work);
401 EXPORT_SYMBOL(ieee80211_start_rx_ba_session_offl);
403 void ieee80211_stop_rx_ba_session_offl(struct ieee80211_vif *vif,
404 const u8 *addr, u16 tid)
406 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
407 struct ieee80211_local *local = sdata->local;
408 struct ieee80211_rx_agg *rx_agg;
409 struct sk_buff *skb = dev_alloc_skb(0);
414 rx_agg = (struct ieee80211_rx_agg *) &skb->cb;
415 memcpy(&rx_agg->addr, addr, ETH_ALEN);
418 skb->pkt_type = IEEE80211_SDATA_QUEUE_RX_AGG_STOP;
419 skb_queue_tail(&sdata->skb_queue, skb);
420 ieee80211_queue_work(&local->hw, &sdata->work);
422 EXPORT_SYMBOL(ieee80211_stop_rx_ba_session_offl);