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