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 #include "driver-ops.h"
  20
  21 static void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
  22                                             u16 initiator, u16 reason,
  23                                             bool from_timer)
  24 {
  25         struct ieee80211_local *local = sta->local;
  26         struct tid_ampdu_rx *tid_rx;
  27         int i;
  28
  29         spin_lock_bh(&sta->lock);
  30
  31         /* check if TID is in operational state */
  32         if (!sta->ampdu_mlme.tid_active_rx[tid]) {
  33                 spin_unlock_bh(&sta->lock);
  34                 return;
  35         }
  36
  37         sta->ampdu_mlme.tid_active_rx[tid] = false;
  38
  39         tid_rx = sta->ampdu_mlme.tid_rx[tid];
  40
  41 #ifdef CONFIG_MAC80211_HT_DEBUG
  42         printk(KERN_DEBUG "Rx BA session stop requested for %pM tid %u\n",
  43                sta->sta.addr, tid);
  44 #endif /* CONFIG_MAC80211_HT_DEBUG */
  45
  46         if (drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_STOP,
  47                              &sta->sta, tid, NULL))
  48                 printk(KERN_DEBUG "HW problem - can not stop rx "
  49                                 "aggregation for tid %d\n", tid);
  50
  51         /* check if this is a self generated aggregation halt */
  52         if (initiator == WLAN_BACK_RECIPIENT)
  53                 ieee80211_send_delba(sta->sdata, sta->sta.addr,
  54                                      tid, 0, reason);
  55
  56         /* free the reordering buffer */
  57         for (i = 0; i < tid_rx->buf_size; i++) {
  58                 if (tid_rx->reorder_buf[i]) {
  59                         /* release the reordered frames */
  60                         dev_kfree_skb(tid_rx->reorder_buf[i]);
  61                         tid_rx->stored_mpdu_num--;
  62                         tid_rx->reorder_buf[i] = NULL;
  63                 }
  64         }
  65
  66         /* free resources */
  67         kfree(tid_rx->reorder_buf);
  68         kfree(tid_rx->reorder_time);
  69         sta->ampdu_mlme.tid_rx[tid] = NULL;
  70
  71         spin_unlock_bh(&sta->lock);
  72
  73         if (!from_timer)
  74                 del_timer_sync(&tid_rx->session_timer);
  75         kfree(tid_rx);
  76 }
  77
  78 void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
  79                                     u16 initiator, u16 reason)
  80 {
  81         ___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, false);
  82 }
  83
  84 /*
  85  * After accepting the AddBA Request we activated a timer,
  86  * resetting it after each frame that arrives from the originator.
  87  */
  88 static void sta_rx_agg_session_timer_expired(unsigned long data)
  89 {
  90         /* not an elegant detour, but there is no choice as the timer passes
  91          * only one argument, and various sta_info are needed here, so init
  92          * flow in sta_info_create gives the TID as data, while the timer_to_id
  93          * array gives the sta through container_of */
  94         u8 *ptid = (u8 *)data;
  95         u8 *timer_to_id = ptid - *ptid;
  96         struct sta_info *sta = container_of(timer_to_id, struct sta_info,
  97                                          timer_to_tid[0]);
  98
  99 #ifdef CONFIG_MAC80211_HT_DEBUG
 100         printk(KERN_DEBUG "rx session timer expired on tid %d\n", (u16)*ptid);
 101 #endif
 102         ___ieee80211_stop_rx_ba_session(sta, *ptid, WLAN_BACK_RECIPIENT,
 103                                         WLAN_REASON_QSTA_TIMEOUT, true);
 104 }
 105
 106 static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
 107                                       u8 dialog_token, u16 status, u16 policy,
 108                                       u16 buf_size, u16 timeout)
 109 {
 110         struct ieee80211_local *local = sdata->local;
 111         struct sk_buff *skb;
 112         struct ieee80211_mgmt *mgmt;
 113         u16 capab;
 114
 115         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 116
 117         if (!skb) {
 118                 printk(KERN_DEBUG "%s: failed to allocate buffer "
 119                        "for addba resp frame\n", sdata->name);
 120                 return;
 121         }
 122
 123         skb_reserve(skb, local->hw.extra_tx_headroom);
 124         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 125         memset(mgmt, 0, 24);
 126         memcpy(mgmt->da, da, ETH_ALEN);
 127         memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
 128         if (sdata->vif.type == NL80211_IFTYPE_AP ||
 129             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 130                 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 131         else if (sdata->vif.type == NL80211_IFTYPE_STATION)
 132                 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 133
 134         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 135                                           IEEE80211_STYPE_ACTION);
 136
 137         skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
 138         mgmt->u.action.category = WLAN_CATEGORY_BACK;
 139         mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
 140         mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
 141
 142         capab = (u16)(policy << 1);     /* bit 1 aggregation policy */
 143         capab |= (u16)(tid << 2);       /* bit 5:2 TID number */
 144         capab |= (u16)(buf_size << 6);  /* bit 15:6 max size of aggregation */
 145
 146         mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
 147         mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
 148         mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
 149
 150         ieee80211_tx_skb(sdata, skb);
 151 }
 152
 153 void ieee80211_process_addba_request(struct ieee80211_local *local,
 154                                      struct sta_info *sta,
 155                                      struct ieee80211_mgmt *mgmt,
 156                                      size_t len)
 157 {
 158         struct ieee80211_hw *hw = &local->hw;
 159         struct ieee80211_conf *conf = &hw->conf;
 160         struct tid_ampdu_rx *tid_agg_rx;
 161         u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num, status;
 162         u8 dialog_token;
 163         int ret = -EOPNOTSUPP;
 164
 165         /* extract session parameters from addba request frame */
 166         dialog_token = mgmt->u.action.u.addba_req.dialog_token;
 167         timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
 168         start_seq_num =
 169                 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
 170
 171         capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
 172         ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
 173         tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
 174         buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
 175
 176         status = WLAN_STATUS_REQUEST_DECLINED;
 177
 178         if (test_sta_flags(sta, WLAN_STA_BLOCK_BA)) {
 179 #ifdef CONFIG_MAC80211_HT_DEBUG
 180                 printk(KERN_DEBUG "Suspend in progress. "
 181                        "Denying ADDBA request\n");
 182 #endif
 183                 goto end_no_lock;
 184         }
 185
 186         /* sanity check for incoming parameters:
 187          * check if configuration can support the BA policy
 188          * and if buffer size does not exceeds max value */
 189         /* XXX: check own ht delayed BA capability?? */
 190         if (((ba_policy != 1) &&
 191              (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
 192             (buf_size > IEEE80211_MAX_AMPDU_BUF)) {
 193                 status = WLAN_STATUS_INVALID_QOS_PARAM;
 194 #ifdef CONFIG_MAC80211_HT_DEBUG
 195                 if (net_ratelimit())
 196                         printk(KERN_DEBUG "AddBA Req with bad params from "
 197                                 "%pM on tid %u. policy %d, buffer size %d\n",
 198                                 mgmt->sa, tid, ba_policy,
 199                                 buf_size);
 200 #endif /* CONFIG_MAC80211_HT_DEBUG */
 201                 goto end_no_lock;
 202         }
 203         /* determine default buffer size */
 204         if (buf_size == 0) {
 205                 struct ieee80211_supported_band *sband;
 206
 207                 sband = local->hw.wiphy->bands[conf->channel->band];
 208                 buf_size = IEEE80211_MIN_AMPDU_BUF;
 209                 buf_size = buf_size << sband->ht_cap.ampdu_factor;
 210         }
 211
 212
 213         /* examine state machine */
 214         spin_lock_bh(&sta->lock);
 215
 216         if (sta->ampdu_mlme.tid_active_rx[tid]) {
 217 #ifdef CONFIG_MAC80211_HT_DEBUG
 218                 if (net_ratelimit())
 219                         printk(KERN_DEBUG "unexpected AddBA Req from "
 220                                 "%pM on tid %u\n",
 221                                 mgmt->sa, tid);
 222 #endif /* CONFIG_MAC80211_HT_DEBUG */
 223                 goto end;
 224         }
 225
 226         /* prepare A-MPDU MLME for Rx aggregation */
 227         sta->ampdu_mlme.tid_rx[tid] =
 228                         kmalloc(sizeof(struct tid_ampdu_rx), GFP_ATOMIC);
 229         if (!sta->ampdu_mlme.tid_rx[tid]) {
 230 #ifdef CONFIG_MAC80211_HT_DEBUG
 231                 if (net_ratelimit())
 232                         printk(KERN_ERR "allocate rx mlme to tid %d failed\n",
 233                                         tid);
 234 #endif
 235                 goto end;
 236         }
 237         /* rx timer */
 238         sta->ampdu_mlme.tid_rx[tid]->session_timer.function =
 239                                 sta_rx_agg_session_timer_expired;
 240         sta->ampdu_mlme.tid_rx[tid]->session_timer.data =
 241                                 (unsigned long)&sta->timer_to_tid[tid];
 242         init_timer(&sta->ampdu_mlme.tid_rx[tid]->session_timer);
 243
 244         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
 245
 246         /* prepare reordering buffer */
 247         tid_agg_rx->reorder_buf =
 248                 kcalloc(buf_size, sizeof(struct sk_buff *), GFP_ATOMIC);
 249         tid_agg_rx->reorder_time =
 250                 kcalloc(buf_size, sizeof(unsigned long), GFP_ATOMIC);
 251         if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
 252 #ifdef CONFIG_MAC80211_HT_DEBUG
 253                 if (net_ratelimit())
 254                         printk(KERN_ERR "can not allocate reordering buffer "
 255                                "to tid %d\n", tid);
 256 #endif
 257                 kfree(tid_agg_rx->reorder_buf);
 258                 kfree(tid_agg_rx->reorder_time);
 259                 kfree(sta->ampdu_mlme.tid_rx[tid]);
 260                 sta->ampdu_mlme.tid_rx[tid] = NULL;
 261                 goto end;
 262         }
 263
 264         ret = drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_START,
 265                                &sta->sta, tid, &start_seq_num);
 266 #ifdef CONFIG_MAC80211_HT_DEBUG
 267         printk(KERN_DEBUG "Rx A-MPDU request on tid %d result %d\n", tid, ret);
 268 #endif /* CONFIG_MAC80211_HT_DEBUG */
 269
 270         if (ret) {
 271                 kfree(tid_agg_rx->reorder_buf);
 272                 kfree(tid_agg_rx);
 273                 sta->ampdu_mlme.tid_rx[tid] = NULL;
 274                 goto end;
 275         }
 276
 277         /* change state and send addba resp */
 278         sta->ampdu_mlme.tid_active_rx[tid] = true;
 279         tid_agg_rx->dialog_token = dialog_token;
 280         tid_agg_rx->ssn = start_seq_num;
 281         tid_agg_rx->head_seq_num = start_seq_num;
 282         tid_agg_rx->buf_size = buf_size;
 283         tid_agg_rx->timeout = timeout;
 284         tid_agg_rx->stored_mpdu_num = 0;
 285         status = WLAN_STATUS_SUCCESS;
 286 end:
 287         spin_unlock_bh(&sta->lock);
 288
 289 end_no_lock:
 290         ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
 291                                   dialog_token, status, 1, buf_size, timeout);
 292 }