net/mac80211/ht.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/wireless.h>
  18 #include <net/mac80211.h>
  19 #include "ieee80211_i.h"
  20 #include "sta_info.h"
  21 #include "wme.h"
  22
  23 int ieee80211_ht_cap_ie_to_ht_info(struct ieee80211_ht_cap *ht_cap_ie,
  24                                    struct ieee80211_ht_info *ht_info)
  25 {
  26
  27         if (ht_info == NULL)
  28                 return -EINVAL;
  29
  30         memset(ht_info, 0, sizeof(*ht_info));
  31
  32         if (ht_cap_ie) {
  33                 u8 ampdu_info = ht_cap_ie->ampdu_params_info;
  34
  35                 ht_info->ht_supported = 1;
  36                 ht_info->cap = le16_to_cpu(ht_cap_ie->cap_info);
  37                 ht_info->ampdu_factor =
  38                         ampdu_info & IEEE80211_HT_CAP_AMPDU_FACTOR;
  39                 ht_info->ampdu_density =
  40                         (ampdu_info & IEEE80211_HT_CAP_AMPDU_DENSITY) >> 2;
  41                 memcpy(ht_info->supp_mcs_set, ht_cap_ie->supp_mcs_set, 16);
  42         } else
  43                 ht_info->ht_supported = 0;
  44
  45         return 0;
  46 }
  47
  48 int ieee80211_ht_addt_info_ie_to_ht_bss_info(
  49                         struct ieee80211_ht_addt_info *ht_add_info_ie,
  50                         struct ieee80211_ht_bss_info *bss_info)
  51 {
  52         if (bss_info == NULL)
  53                 return -EINVAL;
  54
  55         memset(bss_info, 0, sizeof(*bss_info));
  56
  57         if (ht_add_info_ie) {
  58                 u16 op_mode;
  59                 op_mode = le16_to_cpu(ht_add_info_ie->operation_mode);
  60
  61                 bss_info->primary_channel = ht_add_info_ie->control_chan;
  62                 bss_info->bss_cap = ht_add_info_ie->ht_param;
  63                 bss_info->bss_op_mode = (u8)(op_mode & 0xff);
  64         }
  65
  66         return 0;
  67 }
  68
  69 static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
  70                                          const u8 *da, u16 tid,
  71                                          u8 dialog_token, u16 start_seq_num,
  72                                          u16 agg_size, u16 timeout)
  73 {
  74         struct ieee80211_local *local = sdata->local;
  75         struct ieee80211_if_sta *ifsta = &sdata->u.sta;
  76         struct sk_buff *skb;
  77         struct ieee80211_mgmt *mgmt;
  78         u16 capab;
  79
  80         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
  81
  82         if (!skb) {
  83                 printk(KERN_ERR "%s: failed to allocate buffer "
  84                                 "for addba request frame\n", sdata->dev->name);
  85                 return;
  86         }
  87         skb_reserve(skb, local->hw.extra_tx_headroom);
  88         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
  89         memset(mgmt, 0, 24);
  90         memcpy(mgmt->da, da, ETH_ALEN);
  91         memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
  92         if (sdata->vif.type == NL80211_IFTYPE_AP)
  93                 memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
  94         else
  95                 memcpy(mgmt->bssid, ifsta->bssid, ETH_ALEN);
  96
  97         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  98                                           IEEE80211_STYPE_ACTION);
  99
 100         skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
 101
 102         mgmt->u.action.category = WLAN_CATEGORY_BACK;
 103         mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
 104
 105         mgmt->u.action.u.addba_req.dialog_token = dialog_token;
 106         capab = (u16)(1 << 1);          /* bit 1 aggregation policy */
 107         capab |= (u16)(tid << 2);       /* bit 5:2 TID number */
 108         capab |= (u16)(agg_size << 6);  /* bit 15:6 max size of aggergation */
 109
 110         mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
 111
 112         mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
 113         mgmt->u.action.u.addba_req.start_seq_num =
 114                                         cpu_to_le16(start_seq_num << 4);
 115
 116         ieee80211_tx_skb(sdata, skb, 0);
 117 }
 118
 119 static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
 120                                       u8 dialog_token, u16 status, u16 policy,
 121                                       u16 buf_size, u16 timeout)
 122 {
 123         struct ieee80211_if_sta *ifsta = &sdata->u.sta;
 124         struct ieee80211_local *local = sdata->local;
 125         struct sk_buff *skb;
 126         struct ieee80211_mgmt *mgmt;
 127         u16 capab;
 128
 129         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 130
 131         if (!skb) {
 132                 printk(KERN_DEBUG "%s: failed to allocate buffer "
 133                        "for addba resp frame\n", sdata->dev->name);
 134                 return;
 135         }
 136
 137         skb_reserve(skb, local->hw.extra_tx_headroom);
 138         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 139         memset(mgmt, 0, 24);
 140         memcpy(mgmt->da, da, ETH_ALEN);
 141         memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
 142         if (sdata->vif.type == NL80211_IFTYPE_AP)
 143                 memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
 144         else
 145                 memcpy(mgmt->bssid, ifsta->bssid, ETH_ALEN);
 146         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 147                                           IEEE80211_STYPE_ACTION);
 148
 149         skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
 150         mgmt->u.action.category = WLAN_CATEGORY_BACK;
 151         mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
 152         mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
 153
 154         capab = (u16)(policy << 1);     /* bit 1 aggregation policy */
 155         capab |= (u16)(tid << 2);       /* bit 5:2 TID number */
 156         capab |= (u16)(buf_size << 6);  /* bit 15:6 max size of aggregation */
 157
 158         mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
 159         mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
 160         mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
 161
 162         ieee80211_tx_skb(sdata, skb, 0);
 163 }
 164
 165 static void ieee80211_send_delba(struct ieee80211_sub_if_data *sdata,
 166                                  const u8 *da, u16 tid,
 167                                  u16 initiator, u16 reason_code)
 168 {
 169         struct ieee80211_local *local = sdata->local;
 170         struct ieee80211_if_sta *ifsta = &sdata->u.sta;
 171         struct sk_buff *skb;
 172         struct ieee80211_mgmt *mgmt;
 173         u16 params;
 174
 175         skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
 176
 177         if (!skb) {
 178                 printk(KERN_ERR "%s: failed to allocate buffer "
 179                                         "for delba frame\n", sdata->dev->name);
 180                 return;
 181         }
 182
 183         skb_reserve(skb, local->hw.extra_tx_headroom);
 184         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
 185         memset(mgmt, 0, 24);
 186         memcpy(mgmt->da, da, ETH_ALEN);
 187         memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
 188         if (sdata->vif.type == NL80211_IFTYPE_AP)
 189                 memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
 190         else
 191                 memcpy(mgmt->bssid, ifsta->bssid, ETH_ALEN);
 192         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
 193                                           IEEE80211_STYPE_ACTION);
 194
 195         skb_put(skb, 1 + sizeof(mgmt->u.action.u.delba));
 196
 197         mgmt->u.action.category = WLAN_CATEGORY_BACK;
 198         mgmt->u.action.u.delba.action_code = WLAN_ACTION_DELBA;
 199         params = (u16)(initiator << 11);        /* bit 11 initiator */
 200         params |= (u16)(tid << 12);             /* bit 15:12 TID number */
 201
 202         mgmt->u.action.u.delba.params = cpu_to_le16(params);
 203         mgmt->u.action.u.delba.reason_code = cpu_to_le16(reason_code);
 204
 205         ieee80211_tx_skb(sdata, skb, 0);
 206 }
 207
 208 void ieee80211_send_bar(struct ieee80211_sub_if_data *sdata, u8 *ra, u16 tid, u16 ssn)
 209 {
 210         struct ieee80211_local *local = sdata->local;
 211         struct sk_buff *skb;
 212         struct ieee80211_bar *bar;
 213         u16 bar_control = 0;
 214
 215         skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
 216         if (!skb) {
 217                 printk(KERN_ERR "%s: failed to allocate buffer for "
 218                         "bar frame\n", sdata->dev->name);
 219                 return;
 220         }
 221         skb_reserve(skb, local->hw.extra_tx_headroom);
 222         bar = (struct ieee80211_bar *)skb_put(skb, sizeof(*bar));
 223         memset(bar, 0, sizeof(*bar));
 224         bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
 225                                          IEEE80211_STYPE_BACK_REQ);
 226         memcpy(bar->ra, ra, ETH_ALEN);
 227         memcpy(bar->ta, sdata->dev->dev_addr, ETH_ALEN);
 228         bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
 229         bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
 230         bar_control |= (u16)(tid << 12);
 231         bar->control = cpu_to_le16(bar_control);
 232         bar->start_seq_num = cpu_to_le16(ssn);
 233
 234         ieee80211_tx_skb(sdata, skb, 0);
 235 }
 236
 237 void ieee80211_sta_stop_rx_ba_session(struct ieee80211_sub_if_data *sdata, u8 *ra, u16 tid,
 238                                         u16 initiator, u16 reason)
 239 {
 240         struct ieee80211_local *local = sdata->local;
 241         struct ieee80211_hw *hw = &local->hw;
 242         struct sta_info *sta;
 243         int ret, i;
 244
 245         rcu_read_lock();
 246
 247         sta = sta_info_get(local, ra);
 248         if (!sta) {
 249                 rcu_read_unlock();
 250                 return;
 251         }
 252
 253         /* check if TID is in operational state */
 254         spin_lock_bh(&sta->lock);
 255         if (sta->ampdu_mlme.tid_state_rx[tid]
 256                                 != HT_AGG_STATE_OPERATIONAL) {
 257                 spin_unlock_bh(&sta->lock);
 258                 rcu_read_unlock();
 259                 return;
 260         }
 261         sta->ampdu_mlme.tid_state_rx[tid] =
 262                 HT_AGG_STATE_REQ_STOP_BA_MSK |
 263                 (initiator << HT_AGG_STATE_INITIATOR_SHIFT);
 264         spin_unlock_bh(&sta->lock);
 265
 266         /* stop HW Rx aggregation. ampdu_action existence
 267          * already verified in session init so we add the BUG_ON */
 268         BUG_ON(!local->ops->ampdu_action);
 269
 270 #ifdef CONFIG_MAC80211_HT_DEBUG
 271         printk(KERN_DEBUG "Rx BA session stop requested for %pM tid %u\n",
 272                ra, tid);
 273 #endif /* CONFIG_MAC80211_HT_DEBUG */
 274
 275         ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_RX_STOP,
 276                                        &sta->sta, tid, NULL);
 277         if (ret)
 278                 printk(KERN_DEBUG "HW problem - can not stop rx "
 279                                 "aggregation for tid %d\n", tid);
 280
 281         /* shutdown timer has not expired */
 282         if (initiator != WLAN_BACK_TIMER)
 283                 del_timer_sync(&sta->ampdu_mlme.tid_rx[tid]->session_timer);
 284
 285         /* check if this is a self generated aggregation halt */
 286         if (initiator == WLAN_BACK_RECIPIENT || initiator == WLAN_BACK_TIMER)
 287                 ieee80211_send_delba(sdata, ra, tid, 0, reason);
 288
 289         /* free the reordering buffer */
 290         for (i = 0; i < sta->ampdu_mlme.tid_rx[tid]->buf_size; i++) {
 291                 if (sta->ampdu_mlme.tid_rx[tid]->reorder_buf[i]) {
 292                         /* release the reordered frames */
 293                         dev_kfree_skb(sta->ampdu_mlme.tid_rx[tid]->reorder_buf[i]);
 294                         sta->ampdu_mlme.tid_rx[tid]->stored_mpdu_num--;
 295                         sta->ampdu_mlme.tid_rx[tid]->reorder_buf[i] = NULL;
 296                 }
 297         }
 298         /* free resources */
 299         kfree(sta->ampdu_mlme.tid_rx[tid]->reorder_buf);
 300         kfree(sta->ampdu_mlme.tid_rx[tid]);
 301         sta->ampdu_mlme.tid_rx[tid] = NULL;
 302         sta->ampdu_mlme.tid_state_rx[tid] = HT_AGG_STATE_IDLE;
 303
 304         rcu_read_unlock();
 305 }
 306
 307
 308 /*
 309  * After sending add Block Ack request we activated a timer until
 310  * add Block Ack response will arrive from the recipient.
 311  * If this timer expires sta_addba_resp_timer_expired will be executed.
 312  */
 313 static void sta_addba_resp_timer_expired(unsigned long data)
 314 {
 315         /* not an elegant detour, but there is no choice as the timer passes
 316          * only one argument, and both sta_info and TID are needed, so init
 317          * flow in sta_info_create gives the TID as data, while the timer_to_id
 318          * array gives the sta through container_of */
 319         u16 tid = *(u8 *)data;
 320         struct sta_info *temp_sta = container_of((void *)data,
 321                 struct sta_info, timer_to_tid[tid]);
 322
 323         struct ieee80211_local *local = temp_sta->local;
 324         struct ieee80211_hw *hw = &local->hw;
 325         struct sta_info *sta;
 326         u8 *state;
 327
 328         rcu_read_lock();
 329
 330         sta = sta_info_get(local, temp_sta->sta.addr);
 331         if (!sta) {
 332                 rcu_read_unlock();
 333                 return;
 334         }
 335
 336         state = &sta->ampdu_mlme.tid_state_tx[tid];
 337         /* check if the TID waits for addBA response */
 338         spin_lock_bh(&sta->lock);
 339         if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
 340                 spin_unlock_bh(&sta->lock);
 341                 *state = HT_AGG_STATE_IDLE;
 342 #ifdef CONFIG_MAC80211_HT_DEBUG
 343                 printk(KERN_DEBUG "timer expired on tid %d but we are not "
 344                                 "expecting addBA response there", tid);
 345 #endif
 346                 goto timer_expired_exit;
 347         }
 348
 349 #ifdef CONFIG_MAC80211_HT_DEBUG
 350         printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
 351 #endif
 352
 353         /* go through the state check in stop_BA_session */
 354         *state = HT_AGG_STATE_OPERATIONAL;
 355         spin_unlock_bh(&sta->lock);
 356         ieee80211_stop_tx_ba_session(hw, temp_sta->sta.addr, tid,
 357                                      WLAN_BACK_INITIATOR);
 358
 359 timer_expired_exit:
 360         rcu_read_unlock();
 361 }
 362
 363 void ieee80211_sta_tear_down_BA_sessions(struct ieee80211_sub_if_data *sdata, u8 *addr)
 364 {
 365         struct ieee80211_local *local = sdata->local;
 366         int i;
 367
 368         for (i = 0; i <  STA_TID_NUM; i++) {
 369                 ieee80211_stop_tx_ba_session(&local->hw, addr, i,
 370                                              WLAN_BACK_INITIATOR);
 371                 ieee80211_sta_stop_rx_ba_session(sdata, addr, i,
 372                                                  WLAN_BACK_RECIPIENT,
 373                                                  WLAN_REASON_QSTA_LEAVE_QBSS);
 374         }
 375 }
 376
 377 int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
 378 {
 379         struct ieee80211_local *local = hw_to_local(hw);
 380         struct sta_info *sta;
 381         struct ieee80211_sub_if_data *sdata;
 382         u16 start_seq_num;
 383         u8 *state;
 384         int ret;
 385
 386         if (tid >= STA_TID_NUM)
 387                 return -EINVAL;
 388
 389 #ifdef CONFIG_MAC80211_HT_DEBUG
 390         printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
 391                ra, tid);
 392 #endif /* CONFIG_MAC80211_HT_DEBUG */
 393
 394         rcu_read_lock();
 395
 396         sta = sta_info_get(local, ra);
 397         if (!sta) {
 398 #ifdef CONFIG_MAC80211_HT_DEBUG
 399                 printk(KERN_DEBUG "Could not find the station\n");
 400 #endif
 401                 ret = -ENOENT;
 402                 goto exit;
 403         }
 404
 405         spin_lock_bh(&sta->lock);
 406
 407         /* we have tried too many times, receiver does not want A-MPDU */
 408         if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
 409                 ret = -EBUSY;
 410                 goto err_unlock_sta;
 411         }
 412
 413         state = &sta->ampdu_mlme.tid_state_tx[tid];
 414         /* check if the TID is not in aggregation flow already */
 415         if (*state != HT_AGG_STATE_IDLE) {
 416 #ifdef CONFIG_MAC80211_HT_DEBUG
 417                 printk(KERN_DEBUG "BA request denied - session is not "
 418                                  "idle on tid %u\n", tid);
 419 #endif /* CONFIG_MAC80211_HT_DEBUG */
 420                 ret = -EAGAIN;
 421                 goto err_unlock_sta;
 422         }
 423
 424         /* prepare A-MPDU MLME for Tx aggregation */
 425         sta->ampdu_mlme.tid_tx[tid] =
 426                         kmalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
 427         if (!sta->ampdu_mlme.tid_tx[tid]) {
 428 #ifdef CONFIG_MAC80211_HT_DEBUG
 429                 if (net_ratelimit())
 430                         printk(KERN_ERR "allocate tx mlme to tid %d failed\n",
 431                                         tid);
 432 #endif
 433                 ret = -ENOMEM;
 434                 goto err_unlock_sta;
 435         }
 436         /* Tx timer */
 437         sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.function =
 438                         sta_addba_resp_timer_expired;
 439         sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.data =
 440                         (unsigned long)&sta->timer_to_tid[tid];
 441         init_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
 442
 443         /* create a new queue for this aggregation */
 444         ret = ieee80211_ht_agg_queue_add(local, sta, tid);
 445
 446         /* case no queue is available to aggregation
 447          * don't switch to aggregation */
 448         if (ret) {
 449 #ifdef CONFIG_MAC80211_HT_DEBUG
 450                 printk(KERN_DEBUG "BA request denied - queue unavailable for"
 451                                         " tid %d\n", tid);
 452 #endif /* CONFIG_MAC80211_HT_DEBUG */
 453                 goto err_unlock_queue;
 454         }
 455         sdata = sta->sdata;
 456
 457         /* Ok, the Addba frame hasn't been sent yet, but if the driver calls the
 458          * call back right away, it must see that the flow has begun */
 459         *state |= HT_ADDBA_REQUESTED_MSK;
 460
 461         /* This is slightly racy because the queue isn't stopped */
 462         start_seq_num = sta->tid_seq[tid];
 463
 464         if (local->ops->ampdu_action)
 465                 ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_TX_START,
 466                                                &sta->sta, tid, &start_seq_num);
 467
 468         if (ret) {
 469                 /* No need to requeue the packets in the agg queue, since we
 470                  * held the tx lock: no packet could be enqueued to the newly
 471                  * allocated queue */
 472                 ieee80211_ht_agg_queue_remove(local, sta, tid, 0);
 473 #ifdef CONFIG_MAC80211_HT_DEBUG
 474                 printk(KERN_DEBUG "BA request denied - HW unavailable for"
 475                                         " tid %d\n", tid);
 476 #endif /* CONFIG_MAC80211_HT_DEBUG */
 477                 *state = HT_AGG_STATE_IDLE;
 478                 goto err_unlock_queue;
 479         }
 480
 481         /* Will put all the packets in the new SW queue */
 482         ieee80211_requeue(local, ieee802_1d_to_ac[tid]);
 483         spin_unlock_bh(&sta->lock);
 484
 485         /* send an addBA request */
 486         sta->ampdu_mlme.dialog_token_allocator++;
 487         sta->ampdu_mlme.tid_tx[tid]->dialog_token =
 488                         sta->ampdu_mlme.dialog_token_allocator;
 489         sta->ampdu_mlme.tid_tx[tid]->ssn = start_seq_num;
 490
 491
 492         ieee80211_send_addba_request(sta->sdata, ra, tid,
 493                          sta->ampdu_mlme.tid_tx[tid]->dialog_token,
 494                          sta->ampdu_mlme.tid_tx[tid]->ssn,
 495                          0x40, 5000);
 496         /* activate the timer for the recipient's addBA response */
 497         sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.expires =
 498                                 jiffies + ADDBA_RESP_INTERVAL;
 499         add_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
 500 #ifdef CONFIG_MAC80211_HT_DEBUG
 501         printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
 502 #endif
 503         goto exit;
 504
 505 err_unlock_queue:
 506         kfree(sta->ampdu_mlme.tid_tx[tid]);
 507         sta->ampdu_mlme.tid_tx[tid] = NULL;
 508         ret = -EBUSY;
 509 err_unlock_sta:
 510         spin_unlock_bh(&sta->lock);
 511 exit:
 512         rcu_read_unlock();
 513         return ret;
 514 }
 515 EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
 516
 517 int ieee80211_stop_tx_ba_session(struct ieee80211_hw *hw,
 518                                  u8 *ra, u16 tid,
 519                                  enum ieee80211_back_parties initiator)
 520 {
 521         struct ieee80211_local *local = hw_to_local(hw);
 522         struct sta_info *sta;
 523         u8 *state;
 524         int ret = 0;
 525
 526         if (tid >= STA_TID_NUM)
 527                 return -EINVAL;
 528
 529         rcu_read_lock();
 530         sta = sta_info_get(local, ra);
 531         if (!sta) {
 532                 rcu_read_unlock();
 533                 return -ENOENT;
 534         }
 535
 536         /* check if the TID is in aggregation */
 537         state = &sta->ampdu_mlme.tid_state_tx[tid];
 538         spin_lock_bh(&sta->lock);
 539
 540         if (*state != HT_AGG_STATE_OPERATIONAL) {
 541                 ret = -ENOENT;
 542                 goto stop_BA_exit;
 543         }
 544
 545 #ifdef CONFIG_MAC80211_HT_DEBUG
 546         printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
 547                ra, tid);
 548 #endif /* CONFIG_MAC80211_HT_DEBUG */
 549
 550         ieee80211_stop_queue(hw, sta->tid_to_tx_q[tid]);
 551
 552         *state = HT_AGG_STATE_REQ_STOP_BA_MSK |
 553                 (initiator << HT_AGG_STATE_INITIATOR_SHIFT);
 554
 555         if (local->ops->ampdu_action)
 556                 ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_TX_STOP,
 557                                                &sta->sta, tid, NULL);
 558
 559         /* case HW denied going back to legacy */
 560         if (ret) {
 561                 WARN_ON(ret != -EBUSY);
 562                 *state = HT_AGG_STATE_OPERATIONAL;
 563                 ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);
 564                 goto stop_BA_exit;
 565         }
 566
 567 stop_BA_exit:
 568         spin_unlock_bh(&sta->lock);
 569         rcu_read_unlock();
 570         return ret;
 571 }
 572 EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
 573
 574 void ieee80211_start_tx_ba_cb(struct ieee80211_hw *hw, u8 *ra, u16 tid)
 575 {
 576         struct ieee80211_local *local = hw_to_local(hw);
 577         struct sta_info *sta;
 578         u8 *state;
 579
 580         if (tid >= STA_TID_NUM) {
 581 #ifdef CONFIG_MAC80211_HT_DEBUG
 582                 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
 583                                 tid, STA_TID_NUM);
 584 #endif
 585                 return;
 586         }
 587
 588         rcu_read_lock();
 589         sta = sta_info_get(local, ra);
 590         if (!sta) {
 591                 rcu_read_unlock();
 592 #ifdef CONFIG_MAC80211_HT_DEBUG
 593                 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
 594 #endif
 595                 return;
 596         }
 597
 598         state = &sta->ampdu_mlme.tid_state_tx[tid];
 599         spin_lock_bh(&sta->lock);
 600
 601         if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
 602 #ifdef CONFIG_MAC80211_HT_DEBUG
 603                 printk(KERN_DEBUG "addBA was not requested yet, state is %d\n",
 604                                 *state);
 605 #endif
 606                 spin_unlock_bh(&sta->lock);
 607                 rcu_read_unlock();
 608                 return;
 609         }
 610
 611         WARN_ON_ONCE(*state & HT_ADDBA_DRV_READY_MSK);
 612
 613         *state |= HT_ADDBA_DRV_READY_MSK;
 614
 615         if (*state == HT_AGG_STATE_OPERATIONAL) {
 616 #ifdef CONFIG_MAC80211_HT_DEBUG
 617                 printk(KERN_DEBUG "Aggregation is on for tid %d \n", tid);
 618 #endif
 619                 ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);
 620         }
 621         spin_unlock_bh(&sta->lock);
 622         rcu_read_unlock();
 623 }
 624 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb);
 625
 626 void ieee80211_stop_tx_ba_cb(struct ieee80211_hw *hw, u8 *ra, u8 tid)
 627 {
 628         struct ieee80211_local *local = hw_to_local(hw);
 629         struct sta_info *sta;
 630         u8 *state;
 631         int agg_queue;
 632
 633         if (tid >= STA_TID_NUM) {
 634 #ifdef CONFIG_MAC80211_HT_DEBUG
 635                 printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
 636                                 tid, STA_TID_NUM);
 637 #endif
 638                 return;
 639         }
 640
 641 #ifdef CONFIG_MAC80211_HT_DEBUG
 642         printk(KERN_DEBUG "Stopping Tx BA session for %pM tid %d\n",
 643                ra, tid);
 644 #endif /* CONFIG_MAC80211_HT_DEBUG */
 645
 646         rcu_read_lock();
 647         sta = sta_info_get(local, ra);
 648         if (!sta) {
 649 #ifdef CONFIG_MAC80211_HT_DEBUG
 650                 printk(KERN_DEBUG "Could not find station: %pM\n", ra);
 651 #endif
 652                 rcu_read_unlock();
 653                 return;
 654         }
 655         state = &sta->ampdu_mlme.tid_state_tx[tid];
 656
 657         /* NOTE: no need to use sta->lock in this state check, as
 658          * ieee80211_stop_tx_ba_session will let only one stop call to
 659          * pass through per sta/tid
 660          */
 661         if ((*state & HT_AGG_STATE_REQ_STOP_BA_MSK) == 0) {
 662 #ifdef CONFIG_MAC80211_HT_DEBUG
 663                 printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
 664 #endif
 665                 rcu_read_unlock();
 666                 return;
 667         }
 668
 669         if (*state & HT_AGG_STATE_INITIATOR_MSK)
 670                 ieee80211_send_delba(sta->sdata, ra, tid,
 671                         WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
 672
 673         agg_queue = sta->tid_to_tx_q[tid];
 674
 675         ieee80211_ht_agg_queue_remove(local, sta, tid, 1);
 676
 677         /* We just requeued the all the frames that were in the
 678          * removed queue, and since we might miss a softirq we do
 679          * netif_schedule_queue.  ieee80211_wake_queue is not used
 680          * here as this queue is not necessarily stopped
 681          */
 682         netif_schedule_queue(netdev_get_tx_queue(local->mdev, agg_queue));
 683         spin_lock_bh(&sta->lock);
 684         *state = HT_AGG_STATE_IDLE;
 685         sta->ampdu_mlme.addba_req_num[tid] = 0;
 686         kfree(sta->ampdu_mlme.tid_tx[tid]);
 687         sta->ampdu_mlme.tid_tx[tid] = NULL;
 688         spin_unlock_bh(&sta->lock);
 689
 690         rcu_read_unlock();
 691 }
 692 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb);
 693
 694 void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
 695                                       const u8 *ra, u16 tid)
 696 {
 697         struct ieee80211_local *local = hw_to_local(hw);
 698         struct ieee80211_ra_tid *ra_tid;
 699         struct sk_buff *skb = dev_alloc_skb(0);
 700
 701         if (unlikely(!skb)) {
 702 #ifdef CONFIG_MAC80211_HT_DEBUG
 703                 if (net_ratelimit())
 704                         printk(KERN_WARNING "%s: Not enough memory, "
 705                                "dropping start BA session", skb->dev->name);
 706 #endif
 707                 return;
 708         }
 709         ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
 710         memcpy(&ra_tid->ra, ra, ETH_ALEN);
 711         ra_tid->tid = tid;
 712
 713         skb->pkt_type = IEEE80211_ADDBA_MSG;
 714         skb_queue_tail(&local->skb_queue, skb);
 715         tasklet_schedule(&local->tasklet);
 716 }
 717 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
 718
 719 void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
 720                                      const u8 *ra, u16 tid)
 721 {
 722         struct ieee80211_local *local = hw_to_local(hw);
 723         struct ieee80211_ra_tid *ra_tid;
 724         struct sk_buff *skb = dev_alloc_skb(0);
 725
 726         if (unlikely(!skb)) {
 727 #ifdef CONFIG_MAC80211_HT_DEBUG
 728                 if (net_ratelimit())
 729                         printk(KERN_WARNING "%s: Not enough memory, "
 730                                "dropping stop BA session", skb->dev->name);
 731 #endif
 732                 return;
 733         }
 734         ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
 735         memcpy(&ra_tid->ra, ra, ETH_ALEN);
 736         ra_tid->tid = tid;
 737
 738         skb->pkt_type = IEEE80211_DELBA_MSG;
 739         skb_queue_tail(&local->skb_queue, skb);
 740         tasklet_schedule(&local->tasklet);
 741 }
 742 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
 743
 744 /*
 745  * After accepting the AddBA Request we activated a timer,
 746  * resetting it after each frame that arrives from the originator.
 747  * if this timer expires ieee80211_sta_stop_rx_ba_session will be executed.
 748  */
 749 static void sta_rx_agg_session_timer_expired(unsigned long data)
 750 {
 751         /* not an elegant detour, but there is no choice as the timer passes
 752          * only one argument, and various sta_info are needed here, so init
 753          * flow in sta_info_create gives the TID as data, while the timer_to_id
 754          * array gives the sta through container_of */
 755         u8 *ptid = (u8 *)data;
 756         u8 *timer_to_id = ptid - *ptid;
 757         struct sta_info *sta = container_of(timer_to_id, struct sta_info,
 758                                          timer_to_tid[0]);
 759
 760 #ifdef CONFIG_MAC80211_HT_DEBUG
 761         printk(KERN_DEBUG "rx session timer expired on tid %d\n", (u16)*ptid);
 762 #endif
 763         ieee80211_sta_stop_rx_ba_session(sta->sdata, sta->sta.addr,
 764                                          (u16)*ptid, WLAN_BACK_TIMER,
 765                                          WLAN_REASON_QSTA_TIMEOUT);
 766 }
 767
 768 void ieee80211_process_addba_request(struct ieee80211_local *local,
 769                                      struct sta_info *sta,
 770                                      struct ieee80211_mgmt *mgmt,
 771                                      size_t len)
 772 {
 773         struct ieee80211_hw *hw = &local->hw;
 774         struct ieee80211_conf *conf = &hw->conf;
 775         struct tid_ampdu_rx *tid_agg_rx;
 776         u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num, status;
 777         u8 dialog_token;
 778         int ret = -EOPNOTSUPP;
 779
 780         /* extract session parameters from addba request frame */
 781         dialog_token = mgmt->u.action.u.addba_req.dialog_token;
 782         timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
 783         start_seq_num =
 784                 le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
 785
 786         capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
 787         ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
 788         tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
 789         buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
 790
 791         status = WLAN_STATUS_REQUEST_DECLINED;
 792
 793         /* sanity check for incoming parameters:
 794          * check if configuration can support the BA policy
 795          * and if buffer size does not exceeds max value */
 796         if (((ba_policy != 1)
 797                 && (!(conf->ht_conf.cap & IEEE80211_HT_CAP_DELAY_BA)))
 798                 || (buf_size > IEEE80211_MAX_AMPDU_BUF)) {
 799                 status = WLAN_STATUS_INVALID_QOS_PARAM;
 800 #ifdef CONFIG_MAC80211_HT_DEBUG
 801                 if (net_ratelimit())
 802                         printk(KERN_DEBUG "AddBA Req with bad params from "
 803                                 "%pM on tid %u. policy %d, buffer size %d\n",
 804                                 mgmt->sa, tid, ba_policy,
 805                                 buf_size);
 806 #endif /* CONFIG_MAC80211_HT_DEBUG */
 807                 goto end_no_lock;
 808         }
 809         /* determine default buffer size */
 810         if (buf_size == 0) {
 811                 struct ieee80211_supported_band *sband;
 812
 813                 sband = local->hw.wiphy->bands[conf->channel->band];
 814                 buf_size = IEEE80211_MIN_AMPDU_BUF;
 815                 buf_size = buf_size << sband->ht_info.ampdu_factor;
 816         }
 817
 818
 819         /* examine state machine */
 820         spin_lock_bh(&sta->lock);
 821
 822         if (sta->ampdu_mlme.tid_state_rx[tid] != HT_AGG_STATE_IDLE) {
 823 #ifdef CONFIG_MAC80211_HT_DEBUG
 824                 if (net_ratelimit())
 825                         printk(KERN_DEBUG "unexpected AddBA Req from "
 826                                 "%pM on tid %u\n",
 827                                 mgmt->sa, tid);
 828 #endif /* CONFIG_MAC80211_HT_DEBUG */
 829                 goto end;
 830         }
 831
 832         /* prepare A-MPDU MLME for Rx aggregation */
 833         sta->ampdu_mlme.tid_rx[tid] =
 834                         kmalloc(sizeof(struct tid_ampdu_rx), GFP_ATOMIC);
 835         if (!sta->ampdu_mlme.tid_rx[tid]) {
 836 #ifdef CONFIG_MAC80211_HT_DEBUG
 837                 if (net_ratelimit())
 838                         printk(KERN_ERR "allocate rx mlme to tid %d failed\n",
 839                                         tid);
 840 #endif
 841                 goto end;
 842         }
 843         /* rx timer */
 844         sta->ampdu_mlme.tid_rx[tid]->session_timer.function =
 845                                 sta_rx_agg_session_timer_expired;
 846         sta->ampdu_mlme.tid_rx[tid]->session_timer.data =
 847                                 (unsigned long)&sta->timer_to_tid[tid];
 848         init_timer(&sta->ampdu_mlme.tid_rx[tid]->session_timer);
 849
 850         tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
 851
 852         /* prepare reordering buffer */
 853         tid_agg_rx->reorder_buf =
 854                 kmalloc(buf_size * sizeof(struct sk_buff *), GFP_ATOMIC);
 855         if (!tid_agg_rx->reorder_buf) {
 856 #ifdef CONFIG_MAC80211_HT_DEBUG
 857                 if (net_ratelimit())
 858                         printk(KERN_ERR "can not allocate reordering buffer "
 859                                "to tid %d\n", tid);
 860 #endif
 861                 kfree(sta->ampdu_mlme.tid_rx[tid]);
 862                 goto end;
 863         }
 864         memset(tid_agg_rx->reorder_buf, 0,
 865                 buf_size * sizeof(struct sk_buff *));
 866
 867         if (local->ops->ampdu_action)
 868                 ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_RX_START,
 869                                                &sta->sta, tid, &start_seq_num);
 870 #ifdef CONFIG_MAC80211_HT_DEBUG
 871         printk(KERN_DEBUG "Rx A-MPDU request on tid %d result %d\n", tid, ret);
 872 #endif /* CONFIG_MAC80211_HT_DEBUG */
 873
 874         if (ret) {
 875                 kfree(tid_agg_rx->reorder_buf);
 876                 kfree(tid_agg_rx);
 877                 sta->ampdu_mlme.tid_rx[tid] = NULL;
 878                 goto end;
 879         }
 880
 881         /* change state and send addba resp */
 882         sta->ampdu_mlme.tid_state_rx[tid] = HT_AGG_STATE_OPERATIONAL;
 883         tid_agg_rx->dialog_token = dialog_token;
 884         tid_agg_rx->ssn = start_seq_num;
 885         tid_agg_rx->head_seq_num = start_seq_num;
 886         tid_agg_rx->buf_size = buf_size;
 887         tid_agg_rx->timeout = timeout;
 888         tid_agg_rx->stored_mpdu_num = 0;
 889         status = WLAN_STATUS_SUCCESS;
 890 end:
 891         spin_unlock_bh(&sta->lock);
 892
 893 end_no_lock:
 894         ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
 895                                   dialog_token, status, 1, buf_size, timeout);
 896 }
 897
 898 void ieee80211_process_addba_resp(struct ieee80211_local *local,
 899                                   struct sta_info *sta,
 900                                   struct ieee80211_mgmt *mgmt,
 901                                   size_t len)
 902 {
 903         struct ieee80211_hw *hw = &local->hw;
 904         u16 capab;
 905         u16 tid;
 906         u8 *state;
 907
 908         capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
 909         tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
 910
 911         state = &sta->ampdu_mlme.tid_state_tx[tid];
 912
 913         spin_lock_bh(&sta->lock);
 914
 915         if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
 916                 spin_unlock_bh(&sta->lock);
 917                 return;
 918         }
 919
 920         if (mgmt->u.action.u.addba_resp.dialog_token !=
 921                 sta->ampdu_mlme.tid_tx[tid]->dialog_token) {
 922                 spin_unlock_bh(&sta->lock);
 923 #ifdef CONFIG_MAC80211_HT_DEBUG
 924                 printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
 925 #endif /* CONFIG_MAC80211_HT_DEBUG */
 926                 return;
 927         }
 928
 929         del_timer_sync(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
 930 #ifdef CONFIG_MAC80211_HT_DEBUG
 931         printk(KERN_DEBUG "switched off addBA timer for tid %d \n", tid);
 932 #endif /* CONFIG_MAC80211_HT_DEBUG */
 933         if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
 934                         == WLAN_STATUS_SUCCESS) {
 935                 *state |= HT_ADDBA_RECEIVED_MSK;
 936                 sta->ampdu_mlme.addba_req_num[tid] = 0;
 937
 938                 if (*state == HT_AGG_STATE_OPERATIONAL)
 939                         ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);
 940
 941                 spin_unlock_bh(&sta->lock);
 942         } else {
 943                 sta->ampdu_mlme.addba_req_num[tid]++;
 944                 /* this will allow the state check in stop_BA_session */
 945                 *state = HT_AGG_STATE_OPERATIONAL;
 946                 spin_unlock_bh(&sta->lock);
 947                 ieee80211_stop_tx_ba_session(hw, sta->sta.addr, tid,
 948                                              WLAN_BACK_INITIATOR);
 949         }
 950 }
 951
 952 void ieee80211_process_delba(struct ieee80211_sub_if_data *sdata,
 953                              struct sta_info *sta,
 954                              struct ieee80211_mgmt *mgmt, size_t len)
 955 {
 956         struct ieee80211_local *local = sdata->local;
 957         u16 tid, params;
 958         u16 initiator;
 959
 960         params = le16_to_cpu(mgmt->u.action.u.delba.params);
 961         tid = (params & IEEE80211_DELBA_PARAM_TID_MASK) >> 12;
 962         initiator = (params & IEEE80211_DELBA_PARAM_INITIATOR_MASK) >> 11;
 963
 964 #ifdef CONFIG_MAC80211_HT_DEBUG
 965         if (net_ratelimit())
 966                 printk(KERN_DEBUG "delba from %pM (%s) tid %d reason code %d\n",
 967                         mgmt->sa, initiator ? "initiator" : "recipient", tid,
 968                         mgmt->u.action.u.delba.reason_code);
 969 #endif /* CONFIG_MAC80211_HT_DEBUG */
 970
 971         if (initiator == WLAN_BACK_INITIATOR)
 972                 ieee80211_sta_stop_rx_ba_session(sdata, sta->sta.addr, tid,
 973                                                  WLAN_BACK_INITIATOR, 0);
 974         else { /* WLAN_BACK_RECIPIENT */
 975                 spin_lock_bh(&sta->lock);
 976                 sta->ampdu_mlme.tid_state_tx[tid] =
 977                                 HT_AGG_STATE_OPERATIONAL;
 978                 spin_unlock_bh(&sta->lock);
 979                 ieee80211_stop_tx_ba_session(&local->hw, sta->sta.addr, tid,
 980                                              WLAN_BACK_RECIPIENT);
 981         }
 982 }