mac80211: split IBSS/managed code
[linux-2.6.git] / net / mac80211 / agg-rx.c
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 2007-2008, Intel Corporation
10  *
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.
14  */
15
16 #include <linux/ieee80211.h>
17 #include <net/mac80211.h>
18 #include "ieee80211_i.h"
19
20 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
21                                     u16 initiator, u16 reason)
22 {
23         struct ieee80211_local *local = sta->local;
24         struct ieee80211_hw *hw = &local->hw;
25         int i;
26
27         /* check if TID is in operational state */
28         spin_lock_bh(&sta->lock);
29         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_OPERATIONAL) {
30                 spin_unlock_bh(&sta->lock);
31                 return;
32         }
33
34         sta->ampdu_mlme.tid_state_rx[tid] =
35                 HT_AGG_STATE_REQ_STOP_BA_MSK |
36                 (initiator << HT_AGG_STATE_INITIATOR_SHIFT);
37         spin_unlock_bh(&sta->lock);
38
39 #ifdef CONFIG_MAC80211_HT_DEBUG
40         printk(KERN_DEBUG "Rx BA session stop requested for %pM tid %u\n",
41                sta->sta.addr, tid);
42 #endif /* CONFIG_MAC80211_HT_DEBUG */
43
44         if (local->ops->ampdu_action(hw, IEEE80211_AMPDU_RX_STOP,
45                                      &sta->sta, tid, NULL))
46                 printk(KERN_DEBUG "HW problem - can not stop rx "
47                                 "aggregation for tid %d\n", tid);
48
49         /* shutdown timer has not expired */
50         if (initiator != WLAN_BACK_TIMER)
51                 del_timer_sync(&sta->ampdu_mlme.tid_rx[tid]->session_timer);
52
53         /* check if this is a self generated aggregation halt */
54         if (initiator == WLAN_BACK_RECIPIENT || initiator == WLAN_BACK_TIMER)
55                 ieee80211_send_delba(sta->sdata, sta->sta.addr,
56                                      tid, 0, reason);
57
58         /* free the reordering buffer */
59         for (i = 0; i < sta->ampdu_mlme.tid_rx[tid]->buf_size; i++) {
60                 if (sta->ampdu_mlme.tid_rx[tid]->reorder_buf[i]) {
61                         /* release the reordered frames */
62                         dev_kfree_skb(sta->ampdu_mlme.tid_rx[tid]->reorder_buf[i]);
63                         sta->ampdu_mlme.tid_rx[tid]->stored_mpdu_num--;
64                         sta->ampdu_mlme.tid_rx[tid]->reorder_buf[i] = NULL;
65                 }
66         }
67
68         spin_lock_bh(&sta->lock);
69         /* free resources */
70         kfree(sta->ampdu_mlme.tid_rx[tid]->reorder_buf);
71
72         if (!sta->ampdu_mlme.tid_rx[tid]->shutdown) {
73                 kfree(sta->ampdu_mlme.tid_rx[tid]);
74                 sta->ampdu_mlme.tid_rx[tid] = NULL;
75         }
76
77         sta->ampdu_mlme.tid_state_rx[tid] = HT_AGG_STATE_IDLE;
78         spin_unlock_bh(&sta->lock);
79 }
80
81 void ieee80211_sta_stop_rx_ba_session(struct ieee80211_sub_if_data *sdata, u8 *ra, u16 tid,
82                                         u16 initiator, u16 reason)
83 {
84         struct ieee80211_local *local = sdata->local;
85         struct sta_info *sta;
86
87         /* stop HW Rx aggregation. ampdu_action existence
88          * already verified in session init so we add the BUG_ON */
89         BUG_ON(!local->ops->ampdu_action);
90
91         rcu_read_lock();
92
93         sta = sta_info_get(local, ra);
94         if (!sta) {
95                 rcu_read_unlock();
96                 return;
97         }
98
99         __ieee80211_stop_rx_ba_session(sta, tid, initiator, reason);
100
101         rcu_read_unlock();
102 }
103
104 /*
105  * After accepting the AddBA Request we activated a timer,
106  * resetting it after each frame that arrives from the originator.
107  * if this timer expires ieee80211_sta_stop_rx_ba_session will be executed.
108  */
109 static void sta_rx_agg_session_timer_expired(unsigned long data)
110 {
111         /* not an elegant detour, but there is no choice as the timer passes
112          * only one argument, and various sta_info are needed here, so init
113          * flow in sta_info_create gives the TID as data, while the timer_to_id
114          * array gives the sta through container_of */
115         u8 *ptid = (u8 *)data;
116         u8 *timer_to_id = ptid - *ptid;
117         struct sta_info *sta = container_of(timer_to_id, struct sta_info,
118                                          timer_to_tid[0]);
119
120 #ifdef CONFIG_MAC80211_HT_DEBUG
121         printk(KERN_DEBUG "rx session timer expired on tid %d\n", (u16)*ptid);
122 #endif
123         ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
124                                          (u16)*ptid, WLAN_BACK_TIMER,
125                                          WLAN_REASON_QSTA_TIMEOUT);
126 }
127
128 static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
129                                       u8 dialog_token, u16 status, u16 policy,
130                                       u16 buf_size, u16 timeout)
131 {
132         struct ieee80211_local *local = sdata->local;
133         struct sk_buff *skb;
134         struct ieee80211_mgmt *mgmt;
135         u16 capab;
136
137         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
138
139         if (!skb) {
140                 printk(KERN_DEBUG "%s: failed to allocate buffer "
141                        "for addba resp frame\n", sdata->dev->name);
142                 return;
143         }
144
145         skb_reserve(skb, local->hw.extra_tx_headroom);
146         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
147         memset(mgmt, 0, 24);
148         memcpy(mgmt->da, da, ETH_ALEN);
149         memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
150         if (sdata->vif.type == NL80211_IFTYPE_AP ||
151             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
152                 memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
153         else if (sdata->vif.type == NL80211_IFTYPE_STATION)
154                 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
155
156         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
157                                           IEEE80211_STYPE_ACTION);
158
159         skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
160         mgmt->u.action.category = WLAN_CATEGORY_BACK;
161         mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
162         mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
163
164         capab = (u16)(policy << 1);     /* bit 1 aggregation policy */
165         capab |= (u16)(tid << 2);       /* bit 5:2 TID number */
166         capab |= (u16)(buf_size << 6);  /* bit 15:6 max size of aggregation */
167
168         mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
169         mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
170         mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
171
172         ieee80211_tx_skb(sdata, skb, 1);
173 }
174
175 void ieee80211_process_addba_request(struct ieee80211_local *local,
176                                      struct sta_info *sta,
177                                      struct ieee80211_mgmt *mgmt,
178                                      size_t len)
179 {
180         struct ieee80211_hw *hw = &local->hw;
181         struct ieee80211_conf *conf = &hw->conf;
182         struct tid_ampdu_rx *tid_agg_rx;
183         u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num, status;
184         u8 dialog_token;
185         int ret = -EOPNOTSUPP;
186
187         /* extract session parameters from addba request frame */
188         dialog_token = mgmt->u.action.u.addba_req.dialog_token;
189         timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
190         start_seq_num =
191                 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
192
193         capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
194         ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
195         tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
196         buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
197
198         status = WLAN_STATUS_REQUEST_DECLINED;
199
200         /* sanity check for incoming parameters:
201          * check if configuration can support the BA policy
202          * and if buffer size does not exceeds max value */
203         /* XXX: check own ht delayed BA capability?? */
204         if (((ba_policy != 1)
205                 && (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA)))
206                 || (buf_size > IEEE80211_MAX_AMPDU_BUF)) {
207                 status = WLAN_STATUS_INVALID_QOS_PARAM;
208 #ifdef CONFIG_MAC80211_HT_DEBUG
209                 if (net_ratelimit())
210                         printk(KERN_DEBUG "AddBA Req with bad params from "
211                                 "%pM on tid %u. policy %d, buffer size %d\n",
212                                 mgmt->sa, tid, ba_policy,
213                                 buf_size);
214 #endif /* CONFIG_MAC80211_HT_DEBUG */
215                 goto end_no_lock;
216         }
217         /* determine default buffer size */
218         if (buf_size == 0) {
219                 struct ieee80211_supported_band *sband;
220
221                 sband = local->hw.wiphy->bands[conf->channel->band];
222                 buf_size = IEEE80211_MIN_AMPDU_BUF;
223                 buf_size = buf_size << sband->ht_cap.ampdu_factor;
224         }
225
226
227         /* examine state machine */
228         spin_lock_bh(&sta->lock);
229
230         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_IDLE) {
231 #ifdef CONFIG_MAC80211_HT_DEBUG
232                 if (net_ratelimit())
233                         printk(KERN_DEBUG "unexpected AddBA Req from "
234                                 "%pM on tid %u\n",
235                                 mgmt->sa, tid);
236 #endif /* CONFIG_MAC80211_HT_DEBUG */
237                 goto end;
238         }
239
240         /* prepare A-MPDU MLME for Rx aggregation */
241         sta->ampdu_mlme.tid_rx[tid] =
242                         kmalloc(sizeof(struct tid_ampdu_rx), GFP_ATOMIC);
243         if (!sta->ampdu_mlme.tid_rx[tid]) {
244 #ifdef CONFIG_MAC80211_HT_DEBUG
245                 if (net_ratelimit())
246                         printk(KERN_ERR "allocate rx mlme to tid %d failed\n",
247                                         tid);
248 #endif
249                 goto end;
250         }
251         /* rx timer */
252         sta->ampdu_mlme.tid_rx[tid]->session_timer.function =
253                                 sta_rx_agg_session_timer_expired;
254         sta->ampdu_mlme.tid_rx[tid]->session_timer.data =
255                                 (unsigned long)&sta->timer_to_tid[tid];
256         init_timer(&sta->ampdu_mlme.tid_rx[tid]->session_timer);
257
258         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
259
260         /* prepare reordering buffer */
261         tid_agg_rx->reorder_buf =
262                 kcalloc(buf_size, sizeof(struct sk_buff *), GFP_ATOMIC);
263         if (!tid_agg_rx->reorder_buf) {
264 #ifdef CONFIG_MAC80211_HT_DEBUG
265                 if (net_ratelimit())
266                         printk(KERN_ERR "can not allocate reordering buffer "
267                                "to tid %d\n", tid);
268 #endif
269                 kfree(sta->ampdu_mlme.tid_rx[tid]);
270                 goto end;
271         }
272
273         if (local->ops->ampdu_action)
274                 ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_RX_START,
275                                                &sta->sta, tid, &start_seq_num);
276 #ifdef CONFIG_MAC80211_HT_DEBUG
277         printk(KERN_DEBUG "Rx A-MPDU request on tid %d result %d\n", tid, ret);
278 #endif /* CONFIG_MAC80211_HT_DEBUG */
279
280         if (ret) {
281                 kfree(tid_agg_rx->reorder_buf);
282                 kfree(tid_agg_rx);
283                 sta->ampdu_mlme.tid_rx[tid] = NULL;
284                 goto end;
285         }
286
287         /* change state and send addba resp */
288         sta->ampdu_mlme.tid_state_rx[tid] = HT_AGG_STATE_OPERATIONAL;
289         tid_agg_rx->dialog_token = dialog_token;
290         tid_agg_rx->ssn = start_seq_num;
291         tid_agg_rx->head_seq_num = start_seq_num;
292         tid_agg_rx->buf_size = buf_size;
293         tid_agg_rx->timeout = timeout;
294         tid_agg_rx->stored_mpdu_num = 0;
295         status = WLAN_STATUS_SUCCESS;
296 end:
297         spin_unlock_bh(&sta->lock);
298
299 end_no_lock:
300         ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
301                                   dialog_token, status, 1, buf_size, timeout);
302 }