SAFE public projects git trees. - safe/jmp/linux-2.6/blob - 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_sta_stop_rx_ba_session(struct ieee80211_sub_if_data *sdata, u8 *ra, u16 tid,
  21                                         u16 initiator, u16 reason)
  22 {
  23         struct ieee80211_local *local = sdata->local;
  24         struct ieee80211_hw *hw = &local->hw;
  25         struct sta_info *sta;
  26         int ret, i;
  27
  28         rcu_read_lock();
  29
  30         sta = sta_info_get(local, ra);
  31         if (!sta) {
  32                 rcu_read_unlock();
  33                 return;
  34         }
  35
  36         /* check if TID is in operational state */
  37         spin_lock_bh(&sta->lock);
  38         if (sta->ampdu_mlme.tid_state_rx[tid]
  39                                 != HT_AGG_STATE_OPERATIONAL) {
  40                 spin_unlock_bh(&sta->lock);
  41                 rcu_read_unlock();
  42                 return;
  43         }
  44         sta->ampdu_mlme.tid_state_rx[tid] =
  45                 HT_AGG_STATE_REQ_STOP_BA_MSK |
  46                 (initiator << HT_AGG_STATE_INITIATOR_SHIFT);
  47         spin_unlock_bh(&sta->lock);
  48
  49         /* stop HW Rx aggregation. ampdu_action existence
  50          * already verified in session init so we add the BUG_ON */
  51         BUG_ON(!local->ops->ampdu_action);
  52
  53 #ifdef CONFIG_MAC80211_HT_DEBUG
  54         printk(KERN_DEBUG "Rx BA session stop requested for %pM tid %u\n",
  55                ra, tid);
  56 #endif /* CONFIG_MAC80211_HT_DEBUG */
  57
  58         ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_RX_STOP,
  59                                        &sta->sta, tid, NULL);
  60         if (ret)
  61                 printk(KERN_DEBUG "HW problem - can not stop rx "
  62                                 "aggregation for tid %d\n", tid);
  63
  64         /* shutdown timer has not expired */
  65         if (initiator != WLAN_BACK_TIMER)
  66                 del_timer_sync(&sta->ampdu_mlme.tid_rx[tid]->session_timer);
  67
  68         /* check if this is a self generated aggregation halt */
  69         if (initiator == WLAN_BACK_RECIPIENT || initiator == WLAN_BACK_TIMER)
  70                 ieee80211_send_delba(sdata, ra, tid, 0, reason);
  71
  72         /* free the reordering buffer */
  73         for (i = 0; i < sta->ampdu_mlme.tid_rx[tid]->buf_size; i++) {
  74                 if (sta->ampdu_mlme.tid_rx[tid]->reorder_buf[i]) {
  75                         /* release the reordered frames */
  76                         dev_kfree_skb(sta->ampdu_mlme.tid_rx[tid]->reorder_buf[i]);
  77                         sta->ampdu_mlme.tid_rx[tid]->stored_mpdu_num--;
  78                         sta->ampdu_mlme.tid_rx[tid]->reorder_buf[i] = NULL;
  79                 }
  80         }
  81
  82         spin_lock_bh(&sta->lock);
  83         /* free resources */
  84         kfree(sta->ampdu_mlme.tid_rx[tid]->reorder_buf);
  85
  86         if (!sta->ampdu_mlme.tid_rx[tid]->shutdown) {
  87                 kfree(sta->ampdu_mlme.tid_rx[tid]);
  88                 sta->ampdu_mlme.tid_rx[tid] = NULL;
  89         }
  90
  91         sta->ampdu_mlme.tid_state_rx[tid] = HT_AGG_STATE_IDLE;
  92         spin_unlock_bh(&sta->lock);
  93
  94         rcu_read_unlock();
  95 }
  96
  97 /*
  98  * After accepting the AddBA Request we activated a timer,
  99  * resetting it after each frame that arrives from the originator.
 100  * if this timer expires ieee80211_sta_stop_rx_ba_session will be executed.
 101  */
 102 static void sta_rx_agg_session_timer_expired(unsigned long data)
 103 {
 104         /* not an elegant detour, but there is no choice as the timer passes
 105          * only one argument, and various sta_info are needed here, so init
 106          * flow in sta_info_create gives the TID as data, while the timer_to_id
 107          * array gives the sta through container_of */
 108         u8 *ptid = (u8 *)data;
 109         u8 *timer_to_id = ptid - *ptid;
 110         struct sta_info *sta = container_of(timer_to_id, struct sta_info,
 111                                          timer_to_tid[0]);
 112
 113 #ifdef CONFIG_MAC80211_HT_DEBUG
 114         printk(KERN_DEBUG "rx session timer expired on tid %d\n", (u16)*ptid);
 115 #endif
 116         ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
 117                                          (u16)*ptid, WLAN_BACK_TIMER,
 118                                          WLAN_REASON_QSTA_TIMEOUT);
 119 }
 120
 121 static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
 122                                       u8 dialog_token, u16 status, u16 policy,
 123                                       u16 buf_size, u16 timeout)
 124 {
 125         struct ieee80211_if_sta *ifsta = &sdata->u.sta;
 126         struct ieee80211_local *local = sdata->local;
 127         struct sk_buff *skb;
 128         struct ieee80211_mgmt *mgmt;
 129         u16 capab;
 130
 131         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 132
 133         if (!skb) {
 134                 printk(KERN_DEBUG "%s: failed to allocate buffer "
 135                        "for addba resp frame\n", sdata->dev->name);
 136                 return;
 137         }
 138
 139         skb_reserve(skb, local->hw.extra_tx_headroom);
 140         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 141         memset(mgmt, 0, 24);
 142         memcpy(mgmt->da, da, ETH_ALEN);
 143         memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
 144         if (sdata->vif.type == NL80211_IFTYPE_AP ||
 145             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 146                 memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
 147         else
 148                 memcpy(mgmt->bssid, ifsta->bssid, ETH_ALEN);
 149         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 150                                           IEEE80211_STYPE_ACTION);
 151
 152         skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
 153         mgmt->u.action.category = WLAN_CATEGORY_BACK;
 154         mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
 155         mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
 156
 157         capab = (u16)(policy << 1);     /* bit 1 aggregation policy */
 158         capab |= (u16)(tid << 2);       /* bit 5:2 TID number */
 159         capab |= (u16)(buf_size << 6);  /* bit 15:6 max size of aggregation */
 160
 161         mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
 162         mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
 163         mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
 164
 165         ieee80211_tx_skb(sdata, skb, 1);
 166 }
 167
 168 void ieee80211_process_addba_request(struct ieee80211_local *local,
 169                                      struct sta_info *sta,
 170                                      struct ieee80211_mgmt *mgmt,
 171                                      size_t len)
 172 {
 173         struct ieee80211_hw *hw = &local->hw;
 174         struct ieee80211_conf *conf = &hw->conf;
 175         struct tid_ampdu_rx *tid_agg_rx;
 176         u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num, status;
 177         u8 dialog_token;
 178         int ret = -EOPNOTSUPP;
 179
 180         /* extract session parameters from addba request frame */
 181         dialog_token = mgmt->u.action.u.addba_req.dialog_token;
 182         timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
 183         start_seq_num =
 184                 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
 185
 186         capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
 187         ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
 188         tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
 189         buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
 190
 191         status = WLAN_STATUS_REQUEST_DECLINED;
 192
 193         /* sanity check for incoming parameters:
 194          * check if configuration can support the BA policy
 195          * and if buffer size does not exceeds max value */
 196         /* XXX: check own ht delayed BA capability?? */
 197         if (((ba_policy != 1)
 198                 && (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA)))
 199                 || (buf_size > IEEE80211_MAX_AMPDU_BUF)) {
 200                 status = WLAN_STATUS_INVALID_QOS_PARAM;
 201 #ifdef CONFIG_MAC80211_HT_DEBUG
 202                 if (net_ratelimit())
 203                         printk(KERN_DEBUG "AddBA Req with bad params from "
 204                                 "%pM on tid %u. policy %d, buffer size %d\n",
 205                                 mgmt->sa, tid, ba_policy,
 206                                 buf_size);
 207 #endif /* CONFIG_MAC80211_HT_DEBUG */
 208                 goto end_no_lock;
 209         }
 210         /* determine default buffer size */
 211         if (buf_size == 0) {
 212                 struct ieee80211_supported_band *sband;
 213
 214                 sband = local->hw.wiphy->bands[conf->channel->band];
 215                 buf_size = IEEE80211_MIN_AMPDU_BUF;
 216                 buf_size = buf_size << sband->ht_cap.ampdu_factor;
 217         }
 218
 219
 220         /* examine state machine */
 221         spin_lock_bh(&sta->lock);
 222
 223         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_IDLE) {
 224 #ifdef CONFIG_MAC80211_HT_DEBUG
 225                 if (net_ratelimit())
 226                         printk(KERN_DEBUG "unexpected AddBA Req from "
 227                                 "%pM on tid %u\n",
 228                                 mgmt->sa, tid);
 229 #endif /* CONFIG_MAC80211_HT_DEBUG */
 230                 goto end;
 231         }
 232
 233         /* prepare A-MPDU MLME for Rx aggregation */
 234         sta->ampdu_mlme.tid_rx[tid] =
 235                         kmalloc(sizeof(struct tid_ampdu_rx), GFP_ATOMIC);
 236         if (!sta->ampdu_mlme.tid_rx[tid]) {
 237 #ifdef CONFIG_MAC80211_HT_DEBUG
 238                 if (net_ratelimit())
 239                         printk(KERN_ERR "allocate rx mlme to tid %d failed\n",
 240                                         tid);
 241 #endif
 242                 goto end;
 243         }
 244         /* rx timer */
 245         sta->ampdu_mlme.tid_rx[tid]->session_timer.function =
 246                                 sta_rx_agg_session_timer_expired;
 247         sta->ampdu_mlme.tid_rx[tid]->session_timer.data =
 248                                 (unsigned long)&sta->timer_to_tid[tid];
 249         init_timer(&sta->ampdu_mlme.tid_rx[tid]->session_timer);
 250
 251         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
 252
 253         /* prepare reordering buffer */
 254         tid_agg_rx->reorder_buf =
 255                 kcalloc(buf_size, sizeof(struct sk_buff *), GFP_ATOMIC);
 256         if (!tid_agg_rx->reorder_buf) {
 257 #ifdef CONFIG_MAC80211_HT_DEBUG
 258                 if (net_ratelimit())
 259                         printk(KERN_ERR "can not allocate reordering buffer "
 260                                "to tid %d\n", tid);
 261 #endif
 262                 kfree(sta->ampdu_mlme.tid_rx[tid]);
 263                 goto end;
 264         }
 265
 266         if (local->ops->ampdu_action)
 267                 ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_RX_START,
 268                                                &sta->sta, tid, &start_seq_num);
 269 #ifdef CONFIG_MAC80211_HT_DEBUG
 270         printk(KERN_DEBUG "Rx A-MPDU request on tid %d result %d\n", tid, ret);
 271 #endif /* CONFIG_MAC80211_HT_DEBUG */
 272
 273         if (ret) {
 274                 kfree(tid_agg_rx->reorder_buf);
 275                 kfree(tid_agg_rx);
 276                 sta->ampdu_mlme.tid_rx[tid] = NULL;
 277                 goto end;
 278         }
 279
 280         /* change state and send addba resp */
 281         sta->ampdu_mlme.tid_state_rx[tid] = HT_AGG_STATE_OPERATIONAL;
 282         tid_agg_rx->dialog_token = dialog_token;
 283         tid_agg_rx->ssn = start_seq_num;
 284         tid_agg_rx->head_seq_num = start_seq_num;
 285         tid_agg_rx->buf_size = buf_size;
 286         tid_agg_rx->timeout = timeout;
 287         tid_agg_rx->stored_mpdu_num = 0;
 288         status = WLAN_STATUS_SUCCESS;
 289 end:
 290         spin_unlock_bh(&sta->lock);
 291
 292 end_no_lock:
 293         ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
 294                                   dialog_token, status, 1, buf_size, timeout);
 295 }