LXR linux/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
  21void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
  22                                    u16 initiator, u16 reason)
  23{
  24        struct ieee80211_local *local = sta->local;
  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 (drv_ampdu_action(local, 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        kfree(sta->ampdu_mlme.tid_rx[tid]->reorder_time);
  72
  73        if (!sta->ampdu_mlme.tid_rx[tid]->shutdown) {
  74                kfree(sta->ampdu_mlme.tid_rx[tid]);
  75                sta->ampdu_mlme.tid_rx[tid] = NULL;
  76        }
  77
  78        sta->ampdu_mlme.tid_state_rx[tid] = HT_AGG_STATE_IDLE;
  79        spin_unlock_bh(&sta->lock);
  80}
  81
  82void ieee80211_sta_stop_rx_ba_session(struct ieee80211_sub_if_data *sdata, u8 *ra, u16 tid,
  83                                        u16 initiator, u16 reason)
  84{
  85        struct ieee80211_local *local = sdata->local;
  86        struct sta_info *sta;
  87
  88        rcu_read_lock();
  89
  90        sta = sta_info_get(local, ra);
  91        if (!sta) {
  92                rcu_read_unlock();
  93                return;
  94        }
  95
  96        __ieee80211_stop_rx_ba_session(sta, tid, initiator, reason);
  97
  98        rcu_read_unlock();
  99}
 100
 101/*
 102 * After accepting the AddBA Request we activated a timer,
 103 * resetting it after each frame that arrives from the originator.
 104 * if this timer expires ieee80211_sta_stop_rx_ba_session will be executed.
 105 */
 106static void sta_rx_agg_session_timer_expired(unsigned long data)
 107{
 108        /* not an elegant detour, but there is no choice as the timer passes
 109         * only one argument, and various sta_info are needed here, so init
 110         * flow in sta_info_create gives the TID as data, while the timer_to_id
 111         * array gives the sta through container_of */
 112        u8 *ptid = (u8 *)data;
 113        u8 *timer_to_id = ptid - *ptid;
 114        struct sta_info *sta = container_of(timer_to_id, struct sta_info,
 115                                         timer_to_tid[0]);
 116
 117#ifdef CONFIG_MAC80211_HT_DEBUG
 118        printk(KERN_DEBUG "rx session timer expired on tid %d\n", (u16)*ptid);
 119#endif
 120        ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
 121                                         (u16)*ptid, WLAN_BACK_TIMER,
 122                                         WLAN_REASON_QSTA_TIMEOUT);
 123}
 124
 125static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
 126                                      u8 dialog_token, u16 status, u16 policy,
 127                                      u16 buf_size, u16 timeout)
 128{
 129        struct ieee80211_local *local = sdata->local;
 130        struct sk_buff *skb;
 131        struct ieee80211_mgmt *mgmt;
 132        u16 capab;
 133
 134        skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 135
 136        if (!skb) {
 137                printk(KERN_DEBUG "%s: failed to allocate buffer "
 138                       "for addba resp frame\n", sdata->dev->name);
 139                return;
 140        }
 141
 142        skb_reserve(skb, local->hw.extra_tx_headroom);
 143        mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 144        memset(mgmt, 0, 24);
 145        memcpy(mgmt->da, da, ETH_ALEN);
 146        memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
 147        if (sdata->vif.type == NL80211_IFTYPE_AP ||
 148            sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
 149                memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
 150        else if (sdata->vif.type == NL80211_IFTYPE_STATION)
 151                memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
 152
 153        mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 154                                          IEEE80211_STYPE_ACTION);
 155
 156        skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
 157        mgmt->u.action.category = WLAN_CATEGORY_BACK;
 158        mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
 159        mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
 160
 161        capab = (u16)(policy << 1);     /* bit 1 aggregation policy */
 162        capab |= (u16)(tid << 2);       /* bit 5:2 TID number */
 163        capab |= (u16)(buf_size << 6);  /* bit 15:6 max size of aggregation */
 164
 165        mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
 166        mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
 167        mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
 168
 169        ieee80211_tx_skb(sdata, skb, 1);
 170}
 171
 172void ieee80211_process_addba_request(struct ieee80211_local *local,
 173                                     struct sta_info *sta,
 174                                     struct ieee80211_mgmt *mgmt,
 175                                     size_t len)
 176{
 177        struct ieee80211_hw *hw = &local->hw;
 178        struct ieee80211_conf *conf = &hw->conf;
 179        struct tid_ampdu_rx *tid_agg_rx;
 180        u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num, status;
 181        u8 dialog_token;
 182        int ret = -EOPNOTSUPP;
 183
 184        /* extract session parameters from addba request frame */
 185        dialog_token = mgmt->u.action.u.addba_req.dialog_token;
 186        timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
 187        start_seq_num =
 188                le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
 189
 190        capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
 191        ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
 192        tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
 193        buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
 194
 195        status = WLAN_STATUS_REQUEST_DECLINED;
 196
 197        if (test_sta_flags(sta, WLAN_STA_SUSPEND)) {
 198#ifdef CONFIG_MAC80211_HT_DEBUG
 199                printk(KERN_DEBUG "Suspend in progress. "
 200                       "Denying ADDBA request\n");
 201#endif
 202                goto end_no_lock;
 203        }
 204
 205        /* sanity check for incoming parameters:
 206         * check if configuration can support the BA policy
 207         * and if buffer size does not exceeds max value */
 208        /* XXX: check own ht delayed BA capability?? */
 209        if (((ba_policy != 1)
 210                && (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA)))
 211                || (buf_size > IEEE80211_MAX_AMPDU_BUF)) {
 212                status = WLAN_STATUS_INVALID_QOS_PARAM;
 213#ifdef CONFIG_MAC80211_HT_DEBUG
 214                if (net_ratelimit())
 215                        printk(KERN_DEBUG "AddBA Req with bad params from "
 216                                "%pM on tid %u. policy %d, buffer size %d\n",
 217                                mgmt->sa, tid, ba_policy,
 218                                buf_size);
 219#endif /* CONFIG_MAC80211_HT_DEBUG */
 220                goto end_no_lock;
 221        }
 222        /* determine default buffer size */
 223        if (buf_size == 0) {
 224                struct ieee80211_supported_band *sband;
 225
 226                sband = local->hw.wiphy->bands[conf->channel->band];
 227                buf_size = IEEE80211_MIN_AMPDU_BUF;
 228                buf_size = buf_size << sband->ht_cap.ampdu_factor;
 229        }
 230
 231
 232        /* examine state machine */
 233        spin_lock_bh(&sta->lock);
 234
 235        if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_IDLE) {
 236#ifdef CONFIG_MAC80211_HT_DEBUG
 237                if (net_ratelimit())
 238                        printk(KERN_DEBUG "unexpected AddBA Req from "
 239                                "%pM on tid %u\n",
 240                                mgmt->sa, tid);
 241#endif /* CONFIG_MAC80211_HT_DEBUG */
 242                goto end;
 243        }
 244
 245        /* prepare A-MPDU MLME for Rx aggregation */
 246        sta->ampdu_mlme.tid_rx[tid] =
 247                        kmalloc(sizeof(struct tid_ampdu_rx), GFP_ATOMIC);
 248        if (!sta->ampdu_mlme.tid_rx[tid]) {
 249#ifdef CONFIG_MAC80211_HT_DEBUG
 250                if (net_ratelimit())
 251                        printk(KERN_ERR "allocate rx mlme to tid %d failed\n",
 252                                        tid);
 253#endif
 254                goto end;
 255        }
 256        /* rx timer */
 257        sta->ampdu_mlme.tid_rx[tid]->session_timer.function =
 258                                sta_rx_agg_session_timer_expired;
 259        sta->ampdu_mlme.tid_rx[tid]->session_timer.data =
 260                                (unsigned long)&sta->timer_to_tid[tid];
 261        init_timer(&sta->ampdu_mlme.tid_rx[tid]->session_timer);
 262
 263        tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
 264
 265        /* prepare reordering buffer */
 266        tid_agg_rx->reorder_buf =
 267                kcalloc(buf_size, sizeof(struct sk_buff *), GFP_ATOMIC);
 268        tid_agg_rx->reorder_time =
 269                kcalloc(buf_size, sizeof(unsigned long), GFP_ATOMIC);
 270        if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
 271#ifdef CONFIG_MAC80211_HT_DEBUG
 272                if (net_ratelimit())
 273                        printk(KERN_ERR "can not allocate reordering buffer "
 274                               "to tid %d\n", tid);
 275#endif
 276                kfree(tid_agg_rx->reorder_buf);
 277                kfree(tid_agg_rx->reorder_time);
 278                kfree(sta->ampdu_mlme.tid_rx[tid]);
 279                sta->ampdu_mlme.tid_rx[tid] = NULL;
 280                goto end;
 281        }
 282
 283        ret = drv_ampdu_action(local, IEEE80211_AMPDU_RX_START,
 284                               &sta->sta, tid, &start_seq_num);
 285#ifdef CONFIG_MAC80211_HT_DEBUG
 286        printk(KERN_DEBUG "Rx A-MPDU request on tid %d result %d\n", tid, ret);
 287#endif /* CONFIG_MAC80211_HT_DEBUG */
 288
 289        if (ret) {
 290                kfree(tid_agg_rx->reorder_buf);
 291                kfree(tid_agg_rx);
 292                sta->ampdu_mlme.tid_rx[tid] = NULL;
 293                goto end;
 294        }
 295
 296        /* change state and send addba resp */
 297        sta->ampdu_mlme.tid_state_rx[tid] = HT_AGG_STATE_OPERATIONAL;
 298        tid_agg_rx->dialog_token = dialog_token;
 299        tid_agg_rx->ssn = start_seq_num;
 300        tid_agg_rx->head_seq_num = start_seq_num;
 301        tid_agg_rx->buf_size = buf_size;
 302        tid_agg_rx->timeout = timeout;
 303        tid_agg_rx->stored_mpdu_num = 0;
 304        status = WLAN_STATUS_SUCCESS;
 305end:
 306        spin_unlock_bh(&sta->lock);
 307
 308end_no_lock:
 309        ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
 310                                  dialog_token, status, 1, buf_size, timeout);
 311}
 312