net/mac80211/agg-tx.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 2007-2009, 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 "wme.h"
  20
  21 /**
  22  * DOC: TX aggregation
  23  *
  24  * Aggregation on the TX side requires setting the hardware flag
  25  * %IEEE80211_HW_AMPDU_AGGREGATION as well as, if present, the @ampdu_queues
  26  * hardware parameter to the number of hardware AMPDU queues. If there are no
  27  * hardware queues then the driver will (currently) have to do all frame
  28  * buffering.
  29  *
  30  * When TX aggregation is started by some subsystem (usually the rate control
  31  * algorithm would be appropriate) by calling the
  32  * ieee80211_start_tx_ba_session() function, the driver will be notified via
  33  * its @ampdu_action function, with the %IEEE80211_AMPDU_TX_START action.
  34  *
  35  * In response to that, the driver is later required to call the
  36  * ieee80211_start_tx_ba_cb() (or ieee80211_start_tx_ba_cb_irqsafe())
  37  * function, which will start the aggregation session.
  38  *
  39  * Similarly, when the aggregation session is stopped by
  40  * ieee80211_stop_tx_ba_session(), the driver's @ampdu_action function will
  41  * be called with the action %IEEE80211_AMPDU_TX_STOP. In this case, the
  42  * call must not fail, and the driver must later call ieee80211_stop_tx_ba_cb()
  43  * (or ieee80211_stop_tx_ba_cb_irqsafe()).
  44  */
  45
  46 static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
  47                                          const u8 *da, u16 tid,
  48                                          u8 dialog_token, u16 start_seq_num,
  49                                          u16 agg_size, u16 timeout)
  50 {
  51         struct ieee80211_local *local = sdata->local;
  52         struct ieee80211_if_sta *ifsta = &sdata->u.sta;
  53         struct sk_buff *skb;
  54         struct ieee80211_mgmt *mgmt;
  55         u16 capab;
  56
  57         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
  58
  59         if (!skb) {
  60                 printk(KERN_ERR "%s: failed to allocate buffer "
  61                                 "for addba request frame\n", sdata->dev->name);
  62                 return;
  63         }
  64         skb_reserve(skb, local->hw.extra_tx_headroom);
  65         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
  66         memset(mgmt, 0, 24);
  67         memcpy(mgmt->da, da, ETH_ALEN);
  68         memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
  69         if (sdata->vif.type == NL80211_IFTYPE_AP ||
  70             sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
  71                 memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
  72         else
  73                 memcpy(mgmt->bssid, ifsta->bssid, ETH_ALEN);
  74
  75         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  76                                           IEEE80211_STYPE_ACTION);
  77
  78         skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
  79
  80         mgmt->u.action.category = WLAN_CATEGORY_BACK;
  81         mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
  82
  83         mgmt->u.action.u.addba_req.dialog_token = dialog_token;
  84         capab = (u16)(1 << 1);          /* bit 1 aggregation policy */
  85         capab |= (u16)(tid << 2);       /* bit 5:2 TID number */
  86         capab |= (u16)(agg_size << 6);  /* bit 15:6 max size of aggergation */
  87
  88         mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
  89
  90         mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
  91         mgmt->u.action.u.addba_req.start_seq_num =
  92                                         cpu_to_le16(start_seq_num << 4);
  93
  94         ieee80211_tx_skb(sdata, skb, 1);
  95 }
  96
  97 void ieee80211_send_bar(struct ieee80211_sub_if_data *sdata, u8 *ra, u16 tid, u16 ssn)
  98 {
  99         struct ieee80211_local *local = sdata->local;
 100         struct sk_buff *skb;
 101         struct ieee80211_bar *bar;
 102         u16 bar_control = 0;
 103
 104         skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
 105         if (!skb) {
 106                 printk(KERN_ERR "%s: failed to allocate buffer for "
 107                         "bar frame\n", sdata->dev->name);
 108                 return;
 109         }
 110         skb_reserve(skb, local->hw.extra_tx_headroom);
 111         bar = (struct ieee80211_bar *)skb_put(skb, sizeof(*bar));
 112         memset(bar, 0, sizeof(*bar));
 113         bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
 114                                          IEEE80211_STYPE_BACK_REQ);
 115         memcpy(bar->ra, ra, ETH_ALEN);
 116         memcpy(bar->ta, sdata->dev->dev_addr, ETH_ALEN);
 117         bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
 118         bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
 119         bar_control |= (u16)(tid << 12);
 120         bar->control = cpu_to_le16(bar_control);
 121         bar->start_seq_num = cpu_to_le16(ssn);
 122
 123         ieee80211_tx_skb(sdata, skb, 0);
 124 }
 125
 126 static int __ieee80211_stop_tx_ba_session(struct ieee80211_local *local,
 127                                           struct sta_info *sta, u16 tid,
 128                                           enum ieee80211_back_parties initiator)
 129 {
 130         int ret;
 131         u8 *state;
 132
 133         state = &sta->ampdu_mlme.tid_state_tx[tid];
 134
 135         if (local->hw.ampdu_queues)
 136                 ieee80211_stop_queue(&local->hw, sta->tid_to_tx_q[tid]);
 137
 138         *state = HT_AGG_STATE_REQ_STOP_BA_MSK |
 139                 (initiator << HT_AGG_STATE_INITIATOR_SHIFT);
 140
 141         ret = local->ops->ampdu_action(&local->hw, IEEE80211_AMPDU_TX_STOP,
 142                                        &sta->sta, tid, NULL);
 143
 144         /* HW shall not deny going back to legacy */
 145         if (WARN_ON(ret)) {
 146                 *state = HT_AGG_STATE_OPERATIONAL;
 147                 if (local->hw.ampdu_queues)
 148                         ieee80211_wake_queue(&local->hw, sta->tid_to_tx_q[tid]);
 149         }
 150
 151         return ret;
 152 }
 153
 154 /*
 155  * After sending add Block Ack request we activated a timer until
 156  * add Block Ack response will arrive from the recipient.
 157  * If this timer expires sta_addba_resp_timer_expired will be executed.
 158  */
 159 static void sta_addba_resp_timer_expired(unsigned long data)
 160 {
 161         /* not an elegant detour, but there is no choice as the timer passes
 162          * only one argument, and both sta_info and TID are needed, so init
 163          * flow in sta_info_create gives the TID as data, while the timer_to_id
 164          * array gives the sta through container_of */
 165         u16 tid = *(u8 *)data;
 166         struct sta_info *sta = container_of((void *)data,
 167                 struct sta_info, timer_to_tid[tid]);
 168         struct ieee80211_local *local = sta->local;
 169         u8 *state;
 170
 171         state = &sta->ampdu_mlme.tid_state_tx[tid];
 172
 173         /* check if the TID waits for addBA response */
 174         spin_lock_bh(&sta->lock);
 175         if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
 176                 spin_unlock_bh(&sta->lock);
 177                 *state = HT_AGG_STATE_IDLE;
 178 #ifdef CONFIG_MAC80211_HT_DEBUG
 179                 printk(KERN_DEBUG "timer expired on tid %d but we are not "
 180                                 "expecting addBA response there", tid);
 181 #endif
 182                 return;
 183         }
 184
 185 #ifdef CONFIG_MAC80211_HT_DEBUG
 186         printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
 187 #endif
 188
 189         __ieee80211_stop_tx_ba_session(local, sta, tid, WLAN_BACK_INITIATOR);
 190         spin_unlock_bh(&sta->lock);
 191 }
 192
 193 int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
 194 {
 195         struct ieee80211_local *local = hw_to_local(hw);
 196         struct sta_info *sta;
 197         struct ieee80211_sub_if_data *sdata;
 198         u16 start_seq_num;
 199         u8 *state;
 200         int ret = 0;
 201
 202         if (WARN_ON(!local->ops->ampdu_action))
 203                 return -EINVAL;
 204
 205         if ((tid >= STA_TID_NUM) || !(hw->flags & IEEE80211_HW_AMPDU_AGGREGATION))
 206                 return -EINVAL;
 207
 208 #ifdef CONFIG_MAC80211_HT_DEBUG
 209         printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
 210                ra, tid);
 211 #endif /* CONFIG_MAC80211_HT_DEBUG */
 212
 213         rcu_read_lock();
 214
 215         sta = sta_info_get(local, ra);
 216         if (!sta) {
 217 #ifdef CONFIG_MAC80211_HT_DEBUG
 218                 printk(KERN_DEBUG "Could not find the station\n");
 219 #endif
 220                 ret = -ENOENT;
 221                 goto exit;
 222         }
 223
 224         /*
 225          * The aggregation code is not prepared to handle
 226          * anything but STA/AP due to the BSSID handling.
 227          * IBSS could work in the code but isn't supported
 228          * by drivers or the standard.
 229          */
 230         if (sta->sdata->vif.type != NL80211_IFTYPE_STATION &&
 231             sta->sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
 232             sta->sdata->vif.type != NL80211_IFTYPE_AP) {
 233                 ret = -EINVAL;
 234                 goto exit;
 235         }
 236
 237         spin_lock_bh(&sta->lock);
 238
 239         /* we have tried too many times, receiver does not want A-MPDU */
 240         if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
 241                 ret = -EBUSY;
 242                 goto err_unlock_sta;
 243         }
 244
 245         state = &sta->ampdu_mlme.tid_state_tx[tid];
 246         /* check if the TID is not in aggregation flow already */
 247         if (*state != HT_AGG_STATE_IDLE) {
 248 #ifdef CONFIG_MAC80211_HT_DEBUG
 249                 printk(KERN_DEBUG "BA request denied - session is not "
 250                                  "idle on tid %u\n", tid);
 251 #endif /* CONFIG_MAC80211_HT_DEBUG */
 252                 ret = -EAGAIN;
 253                 goto err_unlock_sta;
 254         }
 255
 256         /* prepare A-MPDU MLME for Tx aggregation */
 257         sta->ampdu_mlme.tid_tx[tid] =
 258                         kmalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
 259         if (!sta->ampdu_mlme.tid_tx[tid]) {
 260 #ifdef CONFIG_MAC80211_HT_DEBUG
 261                 if (net_ratelimit())
 262                         printk(KERN_ERR "allocate tx mlme to tid %d failed\n",
 263                                         tid);
 264 #endif
 265                 ret = -ENOMEM;
 266                 goto err_unlock_sta;
 267         }
 268         /* Tx timer */
 269         sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.function =
 270                         sta_addba_resp_timer_expired;
 271         sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.data =
 272                         (unsigned long)&sta->timer_to_tid[tid];
 273         init_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
 274
 275         if (hw->ampdu_queues) {
 276                 /* create a new queue for this aggregation */
 277                 ret = ieee80211_ht_agg_queue_add(local, sta, tid);
 278
 279                 /* case no queue is available to aggregation
 280                  * don't switch to aggregation */
 281                 if (ret) {
 282 #ifdef CONFIG_MAC80211_HT_DEBUG
 283                         printk(KERN_DEBUG "BA request denied - "
 284                                "queue unavailable for tid %d\n", tid);
 285 #endif /* CONFIG_MAC80211_HT_DEBUG */
 286                         goto err_unlock_queue;
 287                 }
 288         }
 289         sdata = sta->sdata;
 290
 291         /* Ok, the Addba frame hasn't been sent yet, but if the driver calls the
 292          * call back right away, it must see that the flow has begun */
 293         *state |= HT_ADDBA_REQUESTED_MSK;
 294
 295         /* This is slightly racy because the queue isn't stopped */
 296         start_seq_num = sta->tid_seq[tid];
 297
 298         ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_TX_START,
 299                                        &sta->sta, tid, &start_seq_num);
 300
 301         if (ret) {
 302                 /* No need to requeue the packets in the agg queue, since we
 303                  * held the tx lock: no packet could be enqueued to the newly
 304                  * allocated queue */
 305                 if (hw->ampdu_queues)
 306                         ieee80211_ht_agg_queue_remove(local, sta, tid, 0);
 307 #ifdef CONFIG_MAC80211_HT_DEBUG
 308                 printk(KERN_DEBUG "BA request denied - HW unavailable for"
 309                                         " tid %d\n", tid);
 310 #endif /* CONFIG_MAC80211_HT_DEBUG */
 311                 *state = HT_AGG_STATE_IDLE;
 312                 goto err_unlock_queue;
 313         }
 314
 315         /* Will put all the packets in the new SW queue */
 316         if (hw->ampdu_queues)
 317                 ieee80211_requeue(local, ieee802_1d_to_ac[tid]);
 318         spin_unlock_bh(&sta->lock);
 319
 320         /* send an addBA request */
 321         sta->ampdu_mlme.dialog_token_allocator++;
 322         sta->ampdu_mlme.tid_tx[tid]->dialog_token =
 323                         sta->ampdu_mlme.dialog_token_allocator;
 324         sta->ampdu_mlme.tid_tx[tid]->ssn = start_seq_num;
 325
 326
 327         ieee80211_send_addba_request(sta->sdata, ra, tid,
 328                          sta->ampdu_mlme.tid_tx[tid]->dialog_token,
 329                          sta->ampdu_mlme.tid_tx[tid]->ssn,
 330                          0x40, 5000);
 331         /* activate the timer for the recipient's addBA response */
 332         sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.expires =
 333                                 jiffies + ADDBA_RESP_INTERVAL;
 334         add_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
 335 #ifdef CONFIG_MAC80211_HT_DEBUG
 336         printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
 337 #endif
 338         goto exit;
 339
 340 err_unlock_queue:
 341         kfree(sta->ampdu_mlme.tid_tx[tid]);
 342         sta->ampdu_mlme.tid_tx[tid] = NULL;
 343         ret = -EBUSY;
 344 err_unlock_sta:
 345         spin_unlock_bh(&sta->lock);
 346 exit:
 347         rcu_read_unlock();
 348         return ret;
 349 }
 350 EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
 351
 352 void ieee80211_start_tx_ba_cb(struct ieee80211_hw *hw, u8 *ra, u16 tid)
 353 {
 354         struct ieee80211_local *local = hw_to_local(hw);
 355         struct sta_info *sta;
 356         u8 *state;
 357
 358         if (tid >= STA_TID_NUM) {
 359 #ifdef CONFIG_MAC80211_HT_DEBUG
 360                 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
 361                                 tid, STA_TID_NUM);
 362 #endif
 363                 return;
 364         }
 365
 366         rcu_read_lock();
 367         sta = sta_info_get(local, ra);
 368         if (!sta) {
 369                 rcu_read_unlock();
 370 #ifdef CONFIG_MAC80211_HT_DEBUG
 371                 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
 372 #endif
 373                 return;
 374         }
 375
 376         state = &sta->ampdu_mlme.tid_state_tx[tid];
 377         spin_lock_bh(&sta->lock);
 378
 379         if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
 380 #ifdef CONFIG_MAC80211_HT_DEBUG
 381                 printk(KERN_DEBUG "addBA was not requested yet, state is %d\n",
 382                                 *state);
 383 #endif
 384                 spin_unlock_bh(&sta->lock);
 385                 rcu_read_unlock();
 386                 return;
 387         }
 388
 389         WARN_ON_ONCE(*state & HT_ADDBA_DRV_READY_MSK);
 390
 391         *state |= HT_ADDBA_DRV_READY_MSK;
 392
 393         if (*state == HT_AGG_STATE_OPERATIONAL) {
 394 #ifdef CONFIG_MAC80211_HT_DEBUG
 395                 printk(KERN_DEBUG "Aggregation is on for tid %d \n", tid);
 396 #endif
 397                 if (hw->ampdu_queues)
 398                         ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);
 399         }
 400         spin_unlock_bh(&sta->lock);
 401         rcu_read_unlock();
 402 }
 403 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb);
 404
 405 void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
 406                                       const u8 *ra, u16 tid)
 407 {
 408         struct ieee80211_local *local = hw_to_local(hw);
 409         struct ieee80211_ra_tid *ra_tid;
 410         struct sk_buff *skb = dev_alloc_skb(0);
 411
 412         if (unlikely(!skb)) {
 413 #ifdef CONFIG_MAC80211_HT_DEBUG
 414                 if (net_ratelimit())
 415                         printk(KERN_WARNING "%s: Not enough memory, "
 416                                "dropping start BA session", skb->dev->name);
 417 #endif
 418                 return;
 419         }
 420         ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
 421         memcpy(&ra_tid->ra, ra, ETH_ALEN);
 422         ra_tid->tid = tid;
 423
 424         skb->pkt_type = IEEE80211_ADDBA_MSG;
 425         skb_queue_tail(&local->skb_queue, skb);
 426         tasklet_schedule(&local->tasklet);
 427 }
 428 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
 429
 430
 431 int ieee80211_stop_tx_ba_session(struct ieee80211_hw *hw,
 432                                  u8 *ra, u16 tid,
 433                                  enum ieee80211_back_parties initiator)
 434 {
 435         struct ieee80211_local *local = hw_to_local(hw);
 436         struct sta_info *sta;
 437         u8 *state;
 438         int ret = 0;
 439
 440         if (WARN_ON(!local->ops->ampdu_action))
 441                 return -EINVAL;
 442
 443         if (tid >= STA_TID_NUM)
 444                 return -EINVAL;
 445
 446         rcu_read_lock();
 447         sta = sta_info_get(local, ra);
 448         if (!sta) {
 449                 rcu_read_unlock();
 450                 return -ENOENT;
 451         }
 452
 453         /* check if the TID is in aggregation */
 454         state = &sta->ampdu_mlme.tid_state_tx[tid];
 455         spin_lock_bh(&sta->lock);
 456
 457         if (*state != HT_AGG_STATE_OPERATIONAL) {
 458                 ret = -ENOENT;
 459                 goto unlock;
 460         }
 461
 462 #ifdef CONFIG_MAC80211_HT_DEBUG
 463         printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
 464                ra, tid);
 465 #endif /* CONFIG_MAC80211_HT_DEBUG */
 466
 467         ret = __ieee80211_stop_tx_ba_session(local, sta, tid, initiator);
 468
 469  unlock:
 470         spin_unlock_bh(&sta->lock);
 471
 472         rcu_read_unlock();
 473
 474         return ret;
 475 }
 476 EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
 477
 478 void ieee80211_stop_tx_ba_cb(struct ieee80211_hw *hw, u8 *ra, u8 tid)
 479 {
 480         struct ieee80211_local *local = hw_to_local(hw);
 481         struct sta_info *sta;
 482         u8 *state;
 483         int agg_queue;
 484
 485         if (tid >= STA_TID_NUM) {
 486 #ifdef CONFIG_MAC80211_HT_DEBUG
 487                 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
 488                                 tid, STA_TID_NUM);
 489 #endif
 490                 return;
 491         }
 492
 493 #ifdef CONFIG_MAC80211_HT_DEBUG
 494         printk(KERN_DEBUG "Stopping Tx BA session for %pM tid %d\n",
 495                ra, tid);
 496 #endif /* CONFIG_MAC80211_HT_DEBUG */
 497
 498         rcu_read_lock();
 499         sta = sta_info_get(local, ra);
 500         if (!sta) {
 501 #ifdef CONFIG_MAC80211_HT_DEBUG
 502                 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
 503 #endif
 504                 rcu_read_unlock();
 505                 return;
 506         }
 507         state = &sta->ampdu_mlme.tid_state_tx[tid];
 508
 509         /* NOTE: no need to use sta->lock in this state check, as
 510          * ieee80211_stop_tx_ba_session will let only one stop call to
 511          * pass through per sta/tid
 512          */
 513         if ((*state & HT_AGG_STATE_REQ_STOP_BA_MSK) == 0) {
 514 #ifdef CONFIG_MAC80211_HT_DEBUG
 515                 printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
 516 #endif
 517                 rcu_read_unlock();
 518                 return;
 519         }
 520
 521         if (*state & HT_AGG_STATE_INITIATOR_MSK)
 522                 ieee80211_send_delba(sta->sdata, ra, tid,
 523                         WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
 524
 525         if (hw->ampdu_queues) {
 526                 agg_queue = sta->tid_to_tx_q[tid];
 527                 ieee80211_ht_agg_queue_remove(local, sta, tid, 1);
 528
 529                 /* We just requeued the all the frames that were in the
 530                  * removed queue, and since we might miss a softirq we do
 531                  * netif_schedule_queue.  ieee80211_wake_queue is not used
 532                  * here as this queue is not necessarily stopped
 533                  */
 534                 netif_schedule_queue(netdev_get_tx_queue(local->mdev,
 535                                                          agg_queue));
 536         }
 537         spin_lock_bh(&sta->lock);
 538         *state = HT_AGG_STATE_IDLE;
 539         sta->ampdu_mlme.addba_req_num[tid] = 0;
 540         kfree(sta->ampdu_mlme.tid_tx[tid]);
 541         sta->ampdu_mlme.tid_tx[tid] = NULL;
 542         spin_unlock_bh(&sta->lock);
 543
 544         rcu_read_unlock();
 545 }
 546 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb);
 547
 548 void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
 549                                      const u8 *ra, u16 tid)
 550 {
 551         struct ieee80211_local *local = hw_to_local(hw);
 552         struct ieee80211_ra_tid *ra_tid;
 553         struct sk_buff *skb = dev_alloc_skb(0);
 554
 555         if (unlikely(!skb)) {
 556 #ifdef CONFIG_MAC80211_HT_DEBUG
 557                 if (net_ratelimit())
 558                         printk(KERN_WARNING "%s: Not enough memory, "
 559                                "dropping stop BA session", skb->dev->name);
 560 #endif
 561                 return;
 562         }
 563         ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
 564         memcpy(&ra_tid->ra, ra, ETH_ALEN);
 565         ra_tid->tid = tid;
 566
 567         skb->pkt_type = IEEE80211_DELBA_MSG;
 568         skb_queue_tail(&local->skb_queue, skb);
 569         tasklet_schedule(&local->tasklet);
 570 }
 571 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
 572
 573
 574 void ieee80211_process_addba_resp(struct ieee80211_local *local,
 575                                   struct sta_info *sta,
 576                                   struct ieee80211_mgmt *mgmt,
 577                                   size_t len)
 578 {
 579         struct ieee80211_hw *hw = &local->hw;
 580         u16 capab;
 581         u16 tid, start_seq_num;
 582         u8 *state;
 583
 584         capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
 585         tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
 586
 587         state = &sta->ampdu_mlme.tid_state_tx[tid];
 588
 589         spin_lock_bh(&sta->lock);
 590
 591         if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
 592                 spin_unlock_bh(&sta->lock);
 593                 return;
 594         }
 595
 596         if (mgmt->u.action.u.addba_resp.dialog_token !=
 597                 sta->ampdu_mlme.tid_tx[tid]->dialog_token) {
 598                 spin_unlock_bh(&sta->lock);
 599 #ifdef CONFIG_MAC80211_HT_DEBUG
 600                 printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
 601 #endif /* CONFIG_MAC80211_HT_DEBUG */
 602                 return;
 603         }
 604
 605         del_timer_sync(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
 606 #ifdef CONFIG_MAC80211_HT_DEBUG
 607         printk(KERN_DEBUG "switched off addBA timer for tid %d \n", tid);
 608 #endif /* CONFIG_MAC80211_HT_DEBUG */
 609         if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
 610                         == WLAN_STATUS_SUCCESS) {
 611                 *state |= HT_ADDBA_RECEIVED_MSK;
 612                 sta->ampdu_mlme.addba_req_num[tid] = 0;
 613
 614                 if (*state == HT_AGG_STATE_OPERATIONAL &&
 615                     local->hw.ampdu_queues)
 616                         ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);
 617
 618                 if (local->ops->ampdu_action) {
 619                         (void)local->ops->ampdu_action(hw,
 620                                                IEEE80211_AMPDU_TX_RESUME,
 621                                                &sta->sta, tid, &start_seq_num);
 622                 }
 623 #ifdef CONFIG_MAC80211_HT_DEBUG
 624                 printk(KERN_DEBUG "Resuming TX aggregation for tid %d\n", tid);
 625 #endif /* CONFIG_MAC80211_HT_DEBUG */
 626                 spin_unlock_bh(&sta->lock);
 627         } else {
 628                 sta->ampdu_mlme.addba_req_num[tid]++;
 629                 __ieee80211_stop_tx_ba_session(local, sta, tid,
 630                                                WLAN_BACK_INITIATOR);
 631                 spin_unlock_bh(&sta->lock);
 632         }
 633 }