1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * HT handling 4 * 5 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> 6 * Copyright 2002-2005, Instant802 Networks, Inc. 7 * Copyright 2005-2006, Devicescape Software, Inc. 8 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> 9 * Copyright 2007, Michael Wu <flamingice@sourmilk.net> 10 * Copyright 2007-2010, Intel Corporation 11 * Copyright(c) 2015-2017 Intel Deutschland GmbH 12 * Copyright (C) 2018 - 2020 Intel Corporation 13 */ 14 15 #include <linux/ieee80211.h> 16 #include <linux/slab.h> 17 #include <linux/export.h> 18 #include <net/mac80211.h> 19 #include "ieee80211_i.h" 20 #include "driver-ops.h" 21 #include "wme.h" 22 23 /** 24 * DOC: TX A-MPDU aggregation 25 * 26 * Aggregation on the TX side requires setting the hardware flag 27 * %IEEE80211_HW_AMPDU_AGGREGATION. The driver will then be handed 28 * packets with a flag indicating A-MPDU aggregation. The driver 29 * or device is responsible for actually aggregating the frames, 30 * as well as deciding how many and which to aggregate. 31 * 32 * When TX aggregation is started by some subsystem (usually the rate 33 * control algorithm would be appropriate) by calling the 34 * ieee80211_start_tx_ba_session() function, the driver will be 35 * notified via its @ampdu_action function, with the 36 * %IEEE80211_AMPDU_TX_START action. 37 * 38 * In response to that, the driver is later required to call the 39 * ieee80211_start_tx_ba_cb_irqsafe() function, which will really 40 * start the aggregation session after the peer has also responded. 41 * If the peer responds negatively, the session will be stopped 42 * again right away. Note that it is possible for the aggregation 43 * session to be stopped before the driver has indicated that it 44 * is done setting it up, in which case it must not indicate the 45 * setup completion. 46 * 47 * Also note that, since we also need to wait for a response from 48 * the peer, the driver is notified of the completion of the 49 * handshake by the %IEEE80211_AMPDU_TX_OPERATIONAL action to the 50 * @ampdu_action callback. 51 * 52 * Similarly, when the aggregation session is stopped by the peer 53 * or something calling ieee80211_stop_tx_ba_session(), the driver's 54 * @ampdu_action function will be called with the action 55 * %IEEE80211_AMPDU_TX_STOP. In this case, the call must not fail, 56 * and the driver must later call ieee80211_stop_tx_ba_cb_irqsafe(). 57 * Note that the sta can get destroyed before the BA tear down is 58 * complete. 59 */ 60 61 static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata, 62 const u8 *da, u16 tid, 63 u8 dialog_token, u16 start_seq_num, 64 u16 agg_size, u16 timeout) 65 { 66 struct ieee80211_local *local = sdata->local; 67 struct sk_buff *skb; 68 struct ieee80211_mgmt *mgmt; 69 u16 capab; 70 71 skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom); 72 73 if (!skb) 74 return; 75 76 skb_reserve(skb, local->hw.extra_tx_headroom); 77 mgmt = skb_put_zero(skb, 24); 78 memcpy(mgmt->da, da, ETH_ALEN); 79 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 80 if (sdata->vif.type == NL80211_IFTYPE_AP || 81 sdata->vif.type == NL80211_IFTYPE_AP_VLAN || 82 sdata->vif.type == NL80211_IFTYPE_MESH_POINT) 83 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 84 else if (sdata->vif.type == NL80211_IFTYPE_STATION) 85 memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN); 86 else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) 87 memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN); 88 89 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 90 IEEE80211_STYPE_ACTION); 91 92 skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req)); 93 94 mgmt->u.action.category = WLAN_CATEGORY_BACK; 95 mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ; 96 97 mgmt->u.action.u.addba_req.dialog_token = dialog_token; 98 capab = IEEE80211_ADDBA_PARAM_AMSDU_MASK; 99 capab |= IEEE80211_ADDBA_PARAM_POLICY_MASK; 100 capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK); 101 capab |= u16_encode_bits(agg_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK); 102 103 mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab); 104 105 mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout); 106 mgmt->u.action.u.addba_req.start_seq_num = 107 cpu_to_le16(start_seq_num << 4); 108 109 ieee80211_tx_skb(sdata, skb); 110 } 111 112 void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn) 113 { 114 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 115 struct ieee80211_local *local = sdata->local; 116 struct sk_buff *skb; 117 struct ieee80211_bar *bar; 118 u16 bar_control = 0; 119 120 skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom); 121 if (!skb) 122 return; 123 124 skb_reserve(skb, local->hw.extra_tx_headroom); 125 bar = skb_put_zero(skb, sizeof(*bar)); 126 bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL | 127 IEEE80211_STYPE_BACK_REQ); 128 memcpy(bar->ra, ra, ETH_ALEN); 129 memcpy(bar->ta, sdata->vif.addr, ETH_ALEN); 130 bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL; 131 bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA; 132 bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT); 133 bar->control = cpu_to_le16(bar_control); 134 bar->start_seq_num = cpu_to_le16(ssn); 135 136 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT | 137 IEEE80211_TX_CTL_REQ_TX_STATUS; 138 ieee80211_tx_skb_tid(sdata, skb, tid); 139 } 140 EXPORT_SYMBOL(ieee80211_send_bar); 141 142 void ieee80211_assign_tid_tx(struct sta_info *sta, int tid, 143 struct tid_ampdu_tx *tid_tx) 144 { 145 lockdep_assert_held(&sta->ampdu_mlme.mtx); 146 lockdep_assert_held(&sta->lock); 147 rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx); 148 } 149 150 /* 151 * When multiple aggregation sessions on multiple stations 152 * are being created/destroyed simultaneously, we need to 153 * refcount the global queue stop caused by that in order 154 * to not get into a situation where one of the aggregation 155 * setup or teardown re-enables queues before the other is 156 * ready to handle that. 157 * 158 * These two functions take care of this issue by keeping 159 * a global "agg_queue_stop" refcount. 160 */ 161 static void __acquires(agg_queue) 162 ieee80211_stop_queue_agg(struct ieee80211_sub_if_data *sdata, int tid) 163 { 164 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)]; 165 166 /* we do refcounting here, so don't use the queue reason refcounting */ 167 168 if (atomic_inc_return(&sdata->local->agg_queue_stop[queue]) == 1) 169 ieee80211_stop_queue_by_reason( 170 &sdata->local->hw, queue, 171 IEEE80211_QUEUE_STOP_REASON_AGGREGATION, 172 false); 173 __acquire(agg_queue); 174 } 175 176 static void __releases(agg_queue) 177 ieee80211_wake_queue_agg(struct ieee80211_sub_if_data *sdata, int tid) 178 { 179 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)]; 180 181 if (atomic_dec_return(&sdata->local->agg_queue_stop[queue]) == 0) 182 ieee80211_wake_queue_by_reason( 183 &sdata->local->hw, queue, 184 IEEE80211_QUEUE_STOP_REASON_AGGREGATION, 185 false); 186 __release(agg_queue); 187 } 188 189 static void 190 ieee80211_agg_stop_txq(struct sta_info *sta, int tid) 191 { 192 struct ieee80211_txq *txq = sta->sta.txq[tid]; 193 struct ieee80211_sub_if_data *sdata; 194 struct fq *fq; 195 struct txq_info *txqi; 196 197 if (!txq) 198 return; 199 200 txqi = to_txq_info(txq); 201 sdata = vif_to_sdata(txq->vif); 202 fq = &sdata->local->fq; 203 204 /* Lock here to protect against further seqno updates on dequeue */ 205 spin_lock_bh(&fq->lock); 206 set_bit(IEEE80211_TXQ_STOP, &txqi->flags); 207 spin_unlock_bh(&fq->lock); 208 } 209 210 static void 211 ieee80211_agg_start_txq(struct sta_info *sta, int tid, bool enable) 212 { 213 struct ieee80211_txq *txq = sta->sta.txq[tid]; 214 struct txq_info *txqi; 215 216 if (!txq) 217 return; 218 219 txqi = to_txq_info(txq); 220 221 if (enable) 222 set_bit(IEEE80211_TXQ_AMPDU, &txqi->flags); 223 else 224 clear_bit(IEEE80211_TXQ_AMPDU, &txqi->flags); 225 226 clear_bit(IEEE80211_TXQ_STOP, &txqi->flags); 227 local_bh_disable(); 228 rcu_read_lock(); 229 schedule_and_wake_txq(sta->sdata->local, txqi); 230 rcu_read_unlock(); 231 local_bh_enable(); 232 } 233 234 /* 235 * splice packets from the STA's pending to the local pending, 236 * requires a call to ieee80211_agg_splice_finish later 237 */ 238 static void __acquires(agg_queue) 239 ieee80211_agg_splice_packets(struct ieee80211_sub_if_data *sdata, 240 struct tid_ampdu_tx *tid_tx, u16 tid) 241 { 242 struct ieee80211_local *local = sdata->local; 243 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)]; 244 unsigned long flags; 245 246 ieee80211_stop_queue_agg(sdata, tid); 247 248 if (WARN(!tid_tx, 249 "TID %d gone but expected when splicing aggregates from the pending queue\n", 250 tid)) 251 return; 252 253 if (!skb_queue_empty(&tid_tx->pending)) { 254 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 255 /* copy over remaining packets */ 256 skb_queue_splice_tail_init(&tid_tx->pending, 257 &local->pending[queue]); 258 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); 259 } 260 } 261 262 static void __releases(agg_queue) 263 ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid) 264 { 265 ieee80211_wake_queue_agg(sdata, tid); 266 } 267 268 static void ieee80211_remove_tid_tx(struct sta_info *sta, int tid) 269 { 270 struct tid_ampdu_tx *tid_tx; 271 272 lockdep_assert_held(&sta->ampdu_mlme.mtx); 273 lockdep_assert_held(&sta->lock); 274 275 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 276 277 /* 278 * When we get here, the TX path will not be lockless any more wrt. 279 * aggregation, since the OPERATIONAL bit has long been cleared. 280 * Thus it will block on getting the lock, if it occurs. So if we 281 * stop the queue now, we will not get any more packets, and any 282 * that might be being processed will wait for us here, thereby 283 * guaranteeing that no packets go to the tid_tx pending queue any 284 * more. 285 */ 286 287 ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid); 288 289 /* future packets must not find the tid_tx struct any more */ 290 ieee80211_assign_tid_tx(sta, tid, NULL); 291 292 ieee80211_agg_splice_finish(sta->sdata, tid); 293 ieee80211_agg_start_txq(sta, tid, false); 294 295 kfree_rcu(tid_tx, rcu_head); 296 } 297 298 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, 299 enum ieee80211_agg_stop_reason reason) 300 { 301 struct ieee80211_local *local = sta->local; 302 struct tid_ampdu_tx *tid_tx; 303 struct ieee80211_ampdu_params params = { 304 .sta = &sta->sta, 305 .tid = tid, 306 .buf_size = 0, 307 .amsdu = false, 308 .timeout = 0, 309 .ssn = 0, 310 }; 311 int ret; 312 313 lockdep_assert_held(&sta->ampdu_mlme.mtx); 314 315 switch (reason) { 316 case AGG_STOP_DECLINED: 317 case AGG_STOP_LOCAL_REQUEST: 318 case AGG_STOP_PEER_REQUEST: 319 params.action = IEEE80211_AMPDU_TX_STOP_CONT; 320 break; 321 case AGG_STOP_DESTROY_STA: 322 params.action = IEEE80211_AMPDU_TX_STOP_FLUSH; 323 break; 324 default: 325 WARN_ON_ONCE(1); 326 return -EINVAL; 327 } 328 329 spin_lock_bh(&sta->lock); 330 331 /* free struct pending for start, if present */ 332 tid_tx = sta->ampdu_mlme.tid_start_tx[tid]; 333 kfree(tid_tx); 334 sta->ampdu_mlme.tid_start_tx[tid] = NULL; 335 336 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 337 if (!tid_tx) { 338 spin_unlock_bh(&sta->lock); 339 return -ENOENT; 340 } 341 342 /* 343 * if we're already stopping ignore any new requests to stop 344 * unless we're destroying it in which case notify the driver 345 */ 346 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { 347 spin_unlock_bh(&sta->lock); 348 if (reason != AGG_STOP_DESTROY_STA) 349 return -EALREADY; 350 params.action = IEEE80211_AMPDU_TX_STOP_FLUSH_CONT; 351 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 352 WARN_ON_ONCE(ret); 353 return 0; 354 } 355 356 if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) { 357 /* not even started yet! */ 358 ieee80211_assign_tid_tx(sta, tid, NULL); 359 spin_unlock_bh(&sta->lock); 360 kfree_rcu(tid_tx, rcu_head); 361 return 0; 362 } 363 364 set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state); 365 366 ieee80211_agg_stop_txq(sta, tid); 367 368 spin_unlock_bh(&sta->lock); 369 370 ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n", 371 sta->sta.addr, tid); 372 373 del_timer_sync(&tid_tx->addba_resp_timer); 374 del_timer_sync(&tid_tx->session_timer); 375 376 /* 377 * After this packets are no longer handed right through 378 * to the driver but are put onto tid_tx->pending instead, 379 * with locking to ensure proper access. 380 */ 381 clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state); 382 383 /* 384 * There might be a few packets being processed right now (on 385 * another CPU) that have already gotten past the aggregation 386 * check when it was still OPERATIONAL and consequently have 387 * IEEE80211_TX_CTL_AMPDU set. In that case, this code might 388 * call into the driver at the same time or even before the 389 * TX paths calls into it, which could confuse the driver. 390 * 391 * Wait for all currently running TX paths to finish before 392 * telling the driver. New packets will not go through since 393 * the aggregation session is no longer OPERATIONAL. 394 */ 395 if (!local->in_reconfig) 396 synchronize_net(); 397 398 tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ? 399 WLAN_BACK_RECIPIENT : 400 WLAN_BACK_INITIATOR; 401 tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST; 402 403 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 404 405 /* HW shall not deny going back to legacy */ 406 if (WARN_ON(ret)) { 407 /* 408 * We may have pending packets get stuck in this case... 409 * Not bothering with a workaround for now. 410 */ 411 } 412 413 /* 414 * In the case of AGG_STOP_DESTROY_STA, the driver won't 415 * necessarily call ieee80211_stop_tx_ba_cb(), so this may 416 * seem like we can leave the tid_tx data pending forever. 417 * This is true, in a way, but "forever" is only until the 418 * station struct is actually destroyed. In the meantime, 419 * leaving it around ensures that we don't transmit packets 420 * to the driver on this TID which might confuse it. 421 */ 422 423 return 0; 424 } 425 426 /* 427 * After sending add Block Ack request we activated a timer until 428 * add Block Ack response will arrive from the recipient. 429 * If this timer expires sta_addba_resp_timer_expired will be executed. 430 */ 431 static void sta_addba_resp_timer_expired(struct timer_list *t) 432 { 433 struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, addba_resp_timer); 434 struct sta_info *sta = tid_tx->sta; 435 u8 tid = tid_tx->tid; 436 437 /* check if the TID waits for addBA response */ 438 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { 439 ht_dbg(sta->sdata, 440 "timer expired on %pM tid %d not expecting addBA response\n", 441 sta->sta.addr, tid); 442 return; 443 } 444 445 ht_dbg(sta->sdata, "addBA response timer expired on %pM tid %d\n", 446 sta->sta.addr, tid); 447 448 ieee80211_stop_tx_ba_session(&sta->sta, tid); 449 } 450 451 static void ieee80211_send_addba_with_timeout(struct sta_info *sta, 452 struct tid_ampdu_tx *tid_tx) 453 { 454 struct ieee80211_sub_if_data *sdata = sta->sdata; 455 struct ieee80211_local *local = sta->local; 456 u8 tid = tid_tx->tid; 457 u16 buf_size; 458 459 /* activate the timer for the recipient's addBA response */ 460 mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL); 461 ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n", 462 sta->sta.addr, tid); 463 464 spin_lock_bh(&sta->lock); 465 sta->ampdu_mlme.last_addba_req_time[tid] = jiffies; 466 sta->ampdu_mlme.addba_req_num[tid]++; 467 spin_unlock_bh(&sta->lock); 468 469 if (sta->sta.he_cap.has_he) { 470 buf_size = local->hw.max_tx_aggregation_subframes; 471 } else { 472 /* 473 * We really should use what the driver told us it will 474 * transmit as the maximum, but certain APs (e.g. the 475 * LinkSys WRT120N with FW v1.0.07 build 002 Jun 18 2012) 476 * will crash when we use a lower number. 477 */ 478 buf_size = IEEE80211_MAX_AMPDU_BUF_HT; 479 } 480 481 /* send AddBA request */ 482 ieee80211_send_addba_request(sdata, sta->sta.addr, tid, 483 tid_tx->dialog_token, 484 sta->tid_seq[tid] >> 4, 485 buf_size, tid_tx->timeout); 486 487 WARN_ON(test_and_set_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state)); 488 } 489 490 void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid) 491 { 492 struct tid_ampdu_tx *tid_tx; 493 struct ieee80211_local *local = sta->local; 494 struct ieee80211_sub_if_data *sdata = sta->sdata; 495 struct ieee80211_ampdu_params params = { 496 .sta = &sta->sta, 497 .action = IEEE80211_AMPDU_TX_START, 498 .tid = tid, 499 .buf_size = 0, 500 .amsdu = false, 501 .timeout = 0, 502 }; 503 int ret; 504 505 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 506 507 /* 508 * Start queuing up packets for this aggregation session. 509 * We're going to release them once the driver is OK with 510 * that. 511 */ 512 clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state); 513 514 ieee80211_agg_stop_txq(sta, tid); 515 516 /* 517 * Make sure no packets are being processed. This ensures that 518 * we have a valid starting sequence number and that in-flight 519 * packets have been flushed out and no packets for this TID 520 * will go into the driver during the ampdu_action call. 521 */ 522 synchronize_net(); 523 524 params.ssn = sta->tid_seq[tid] >> 4; 525 ret = drv_ampdu_action(local, sdata, ¶ms); 526 if (ret == IEEE80211_AMPDU_TX_START_DELAY_ADDBA) { 527 return; 528 } else if (ret == IEEE80211_AMPDU_TX_START_IMMEDIATE) { 529 /* 530 * We didn't send the request yet, so don't need to check 531 * here if we already got a response, just mark as driver 532 * ready immediately. 533 */ 534 set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state); 535 } else if (ret) { 536 ht_dbg(sdata, 537 "BA request denied - HW unavailable for %pM tid %d\n", 538 sta->sta.addr, tid); 539 spin_lock_bh(&sta->lock); 540 ieee80211_agg_splice_packets(sdata, tid_tx, tid); 541 ieee80211_assign_tid_tx(sta, tid, NULL); 542 ieee80211_agg_splice_finish(sdata, tid); 543 spin_unlock_bh(&sta->lock); 544 545 ieee80211_agg_start_txq(sta, tid, false); 546 547 kfree_rcu(tid_tx, rcu_head); 548 return; 549 } 550 551 ieee80211_send_addba_with_timeout(sta, tid_tx); 552 } 553 554 /* 555 * After accepting the AddBA Response we activated a timer, 556 * resetting it after each frame that we send. 557 */ 558 static void sta_tx_agg_session_timer_expired(struct timer_list *t) 559 { 560 struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, session_timer); 561 struct sta_info *sta = tid_tx->sta; 562 u8 tid = tid_tx->tid; 563 unsigned long timeout; 564 565 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { 566 return; 567 } 568 569 timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout); 570 if (time_is_after_jiffies(timeout)) { 571 mod_timer(&tid_tx->session_timer, timeout); 572 return; 573 } 574 575 ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n", 576 sta->sta.addr, tid); 577 578 ieee80211_stop_tx_ba_session(&sta->sta, tid); 579 } 580 581 int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid, 582 u16 timeout) 583 { 584 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 585 struct ieee80211_sub_if_data *sdata = sta->sdata; 586 struct ieee80211_local *local = sdata->local; 587 struct tid_ampdu_tx *tid_tx; 588 int ret = 0; 589 590 trace_api_start_tx_ba_session(pubsta, tid); 591 592 if (WARN(sta->reserved_tid == tid, 593 "Requested to start BA session on reserved tid=%d", tid)) 594 return -EINVAL; 595 596 if (!pubsta->ht_cap.ht_supported && 597 sta->sdata->vif.bss_conf.chandef.chan->band != NL80211_BAND_6GHZ) 598 return -EINVAL; 599 600 if (WARN_ON_ONCE(!local->ops->ampdu_action)) 601 return -EINVAL; 602 603 if ((tid >= IEEE80211_NUM_TIDS) || 604 !ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) || 605 ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW)) 606 return -EINVAL; 607 608 if (WARN_ON(tid >= IEEE80211_FIRST_TSPEC_TSID)) 609 return -EINVAL; 610 611 ht_dbg(sdata, "Open BA session requested for %pM tid %u\n", 612 pubsta->addr, tid); 613 614 if (sdata->vif.type != NL80211_IFTYPE_STATION && 615 sdata->vif.type != NL80211_IFTYPE_MESH_POINT && 616 sdata->vif.type != NL80211_IFTYPE_AP_VLAN && 617 sdata->vif.type != NL80211_IFTYPE_AP && 618 sdata->vif.type != NL80211_IFTYPE_ADHOC) 619 return -EINVAL; 620 621 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { 622 ht_dbg(sdata, 623 "BA sessions blocked - Denying BA session request %pM tid %d\n", 624 sta->sta.addr, tid); 625 return -EINVAL; 626 } 627 628 /* 629 * 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a 630 * member of an IBSS, and has no other existing Block Ack agreement 631 * with the recipient STA, then the initiating STA shall transmit a 632 * Probe Request frame to the recipient STA and shall not transmit an 633 * ADDBA Request frame unless it receives a Probe Response frame 634 * from the recipient within dot11ADDBAFailureTimeout. 635 * 636 * The probe request mechanism for ADDBA is currently not implemented, 637 * but we only build up Block Ack session with HT STAs. This information 638 * is set when we receive a bss info from a probe response or a beacon. 639 */ 640 if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC && 641 !sta->sta.ht_cap.ht_supported) { 642 ht_dbg(sdata, 643 "BA request denied - IBSS STA %pM does not advertise HT support\n", 644 pubsta->addr); 645 return -EINVAL; 646 } 647 648 spin_lock_bh(&sta->lock); 649 650 /* we have tried too many times, receiver does not want A-MPDU */ 651 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) { 652 ret = -EBUSY; 653 goto err_unlock_sta; 654 } 655 656 /* 657 * if we have tried more than HT_AGG_BURST_RETRIES times we 658 * will spread our requests in time to avoid stalling connection 659 * for too long 660 */ 661 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES && 662 time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] + 663 HT_AGG_RETRIES_PERIOD)) { 664 ht_dbg(sdata, 665 "BA request denied - %d failed requests on %pM tid %u\n", 666 sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid); 667 ret = -EBUSY; 668 goto err_unlock_sta; 669 } 670 671 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 672 /* check if the TID is not in aggregation flow already */ 673 if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) { 674 ht_dbg(sdata, 675 "BA request denied - session is not idle on %pM tid %u\n", 676 sta->sta.addr, tid); 677 ret = -EAGAIN; 678 goto err_unlock_sta; 679 } 680 681 /* prepare A-MPDU MLME for Tx aggregation */ 682 tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC); 683 if (!tid_tx) { 684 ret = -ENOMEM; 685 goto err_unlock_sta; 686 } 687 688 skb_queue_head_init(&tid_tx->pending); 689 __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state); 690 691 tid_tx->timeout = timeout; 692 tid_tx->sta = sta; 693 tid_tx->tid = tid; 694 695 /* response timer */ 696 timer_setup(&tid_tx->addba_resp_timer, sta_addba_resp_timer_expired, 0); 697 698 /* tx timer */ 699 timer_setup(&tid_tx->session_timer, 700 sta_tx_agg_session_timer_expired, TIMER_DEFERRABLE); 701 702 /* assign a dialog token */ 703 sta->ampdu_mlme.dialog_token_allocator++; 704 tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator; 705 706 /* 707 * Finally, assign it to the start array; the work item will 708 * collect it and move it to the normal array. 709 */ 710 sta->ampdu_mlme.tid_start_tx[tid] = tid_tx; 711 712 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 713 714 /* this flow continues off the work */ 715 err_unlock_sta: 716 spin_unlock_bh(&sta->lock); 717 return ret; 718 } 719 EXPORT_SYMBOL(ieee80211_start_tx_ba_session); 720 721 static void ieee80211_agg_tx_operational(struct ieee80211_local *local, 722 struct sta_info *sta, u16 tid) 723 { 724 struct tid_ampdu_tx *tid_tx; 725 struct ieee80211_ampdu_params params = { 726 .sta = &sta->sta, 727 .action = IEEE80211_AMPDU_TX_OPERATIONAL, 728 .tid = tid, 729 .timeout = 0, 730 .ssn = 0, 731 }; 732 733 lockdep_assert_held(&sta->ampdu_mlme.mtx); 734 735 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 736 params.buf_size = tid_tx->buf_size; 737 params.amsdu = tid_tx->amsdu; 738 739 ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n", 740 sta->sta.addr, tid); 741 742 drv_ampdu_action(local, sta->sdata, ¶ms); 743 744 /* 745 * synchronize with TX path, while splicing the TX path 746 * should block so it won't put more packets onto pending. 747 */ 748 spin_lock_bh(&sta->lock); 749 750 ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid); 751 /* 752 * Now mark as operational. This will be visible 753 * in the TX path, and lets it go lock-free in 754 * the common case. 755 */ 756 set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state); 757 ieee80211_agg_splice_finish(sta->sdata, tid); 758 759 spin_unlock_bh(&sta->lock); 760 761 ieee80211_agg_start_txq(sta, tid, true); 762 } 763 764 void ieee80211_start_tx_ba_cb(struct sta_info *sta, int tid, 765 struct tid_ampdu_tx *tid_tx) 766 { 767 struct ieee80211_sub_if_data *sdata = sta->sdata; 768 struct ieee80211_local *local = sdata->local; 769 770 if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))) 771 return; 772 773 if (!test_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state)) { 774 ieee80211_send_addba_with_timeout(sta, tid_tx); 775 /* RESPONSE_RECEIVED state whould trigger the flow again */ 776 return; 777 } 778 779 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) 780 ieee80211_agg_tx_operational(local, sta, tid); 781 } 782 783 static struct tid_ampdu_tx * 784 ieee80211_lookup_tid_tx(struct ieee80211_sub_if_data *sdata, 785 const u8 *ra, u16 tid, struct sta_info **sta) 786 { 787 struct tid_ampdu_tx *tid_tx; 788 789 if (tid >= IEEE80211_NUM_TIDS) { 790 ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n", 791 tid, IEEE80211_NUM_TIDS); 792 return NULL; 793 } 794 795 *sta = sta_info_get_bss(sdata, ra); 796 if (!*sta) { 797 ht_dbg(sdata, "Could not find station: %pM\n", ra); 798 return NULL; 799 } 800 801 tid_tx = rcu_dereference((*sta)->ampdu_mlme.tid_tx[tid]); 802 803 if (WARN_ON(!tid_tx)) 804 ht_dbg(sdata, "addBA was not requested!\n"); 805 806 return tid_tx; 807 } 808 809 void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif, 810 const u8 *ra, u16 tid) 811 { 812 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 813 struct ieee80211_local *local = sdata->local; 814 struct sta_info *sta; 815 struct tid_ampdu_tx *tid_tx; 816 817 trace_api_start_tx_ba_cb(sdata, ra, tid); 818 819 rcu_read_lock(); 820 tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta); 821 if (!tid_tx) 822 goto out; 823 824 set_bit(HT_AGG_STATE_START_CB, &tid_tx->state); 825 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 826 out: 827 rcu_read_unlock(); 828 } 829 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe); 830 831 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, 832 enum ieee80211_agg_stop_reason reason) 833 { 834 int ret; 835 836 mutex_lock(&sta->ampdu_mlme.mtx); 837 838 ret = ___ieee80211_stop_tx_ba_session(sta, tid, reason); 839 840 mutex_unlock(&sta->ampdu_mlme.mtx); 841 842 return ret; 843 } 844 845 int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid) 846 { 847 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 848 struct ieee80211_sub_if_data *sdata = sta->sdata; 849 struct ieee80211_local *local = sdata->local; 850 struct tid_ampdu_tx *tid_tx; 851 int ret = 0; 852 853 trace_api_stop_tx_ba_session(pubsta, tid); 854 855 if (!local->ops->ampdu_action) 856 return -EINVAL; 857 858 if (tid >= IEEE80211_NUM_TIDS) 859 return -EINVAL; 860 861 spin_lock_bh(&sta->lock); 862 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 863 864 if (!tid_tx) { 865 ret = -ENOENT; 866 goto unlock; 867 } 868 869 WARN(sta->reserved_tid == tid, 870 "Requested to stop BA session on reserved tid=%d", tid); 871 872 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { 873 /* already in progress stopping it */ 874 ret = 0; 875 goto unlock; 876 } 877 878 set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state); 879 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 880 881 unlock: 882 spin_unlock_bh(&sta->lock); 883 return ret; 884 } 885 EXPORT_SYMBOL(ieee80211_stop_tx_ba_session); 886 887 void ieee80211_stop_tx_ba_cb(struct sta_info *sta, int tid, 888 struct tid_ampdu_tx *tid_tx) 889 { 890 struct ieee80211_sub_if_data *sdata = sta->sdata; 891 bool send_delba = false; 892 893 ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n", 894 sta->sta.addr, tid); 895 896 spin_lock_bh(&sta->lock); 897 898 if (!test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { 899 ht_dbg(sdata, 900 "unexpected callback to A-MPDU stop for %pM tid %d\n", 901 sta->sta.addr, tid); 902 goto unlock_sta; 903 } 904 905 if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop) 906 send_delba = true; 907 908 ieee80211_remove_tid_tx(sta, tid); 909 910 unlock_sta: 911 spin_unlock_bh(&sta->lock); 912 913 if (send_delba) 914 ieee80211_send_delba(sdata, sta->sta.addr, tid, 915 WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE); 916 } 917 918 void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif, 919 const u8 *ra, u16 tid) 920 { 921 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 922 struct ieee80211_local *local = sdata->local; 923 struct sta_info *sta; 924 struct tid_ampdu_tx *tid_tx; 925 926 trace_api_stop_tx_ba_cb(sdata, ra, tid); 927 928 rcu_read_lock(); 929 tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta); 930 if (!tid_tx) 931 goto out; 932 933 set_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state); 934 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 935 out: 936 rcu_read_unlock(); 937 } 938 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe); 939 940 941 void ieee80211_process_addba_resp(struct ieee80211_local *local, 942 struct sta_info *sta, 943 struct ieee80211_mgmt *mgmt, 944 size_t len) 945 { 946 struct tid_ampdu_tx *tid_tx; 947 struct ieee80211_txq *txq; 948 u16 capab, tid, buf_size; 949 bool amsdu; 950 951 capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab); 952 amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK; 953 tid = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_TID_MASK); 954 buf_size = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK); 955 buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes); 956 957 txq = sta->sta.txq[tid]; 958 if (!amsdu && txq) 959 set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags); 960 961 mutex_lock(&sta->ampdu_mlme.mtx); 962 963 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 964 if (!tid_tx) 965 goto out; 966 967 if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) { 968 ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n", 969 sta->sta.addr, tid); 970 goto out; 971 } 972 973 del_timer_sync(&tid_tx->addba_resp_timer); 974 975 ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n", 976 sta->sta.addr, tid); 977 978 /* 979 * addba_resp_timer may have fired before we got here, and 980 * caused WANT_STOP to be set. If the stop then was already 981 * processed further, STOPPING might be set. 982 */ 983 if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) || 984 test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { 985 ht_dbg(sta->sdata, 986 "got addBA resp for %pM tid %d but we already gave up\n", 987 sta->sta.addr, tid); 988 goto out; 989 } 990 991 /* 992 * IEEE 802.11-2007 7.3.1.14: 993 * In an ADDBA Response frame, when the Status Code field 994 * is set to 0, the Buffer Size subfield is set to a value 995 * of at least 1. 996 */ 997 if (le16_to_cpu(mgmt->u.action.u.addba_resp.status) 998 == WLAN_STATUS_SUCCESS && buf_size) { 999 if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED, 1000 &tid_tx->state)) { 1001 /* ignore duplicate response */ 1002 goto out; 1003 } 1004 1005 tid_tx->buf_size = buf_size; 1006 tid_tx->amsdu = amsdu; 1007 1008 if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)) 1009 ieee80211_agg_tx_operational(local, sta, tid); 1010 1011 sta->ampdu_mlme.addba_req_num[tid] = 0; 1012 1013 tid_tx->timeout = 1014 le16_to_cpu(mgmt->u.action.u.addba_resp.timeout); 1015 1016 if (tid_tx->timeout) { 1017 mod_timer(&tid_tx->session_timer, 1018 TU_TO_EXP_TIME(tid_tx->timeout)); 1019 tid_tx->last_tx = jiffies; 1020 } 1021 1022 } else { 1023 ___ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED); 1024 } 1025 1026 out: 1027 mutex_unlock(&sta->ampdu_mlme.mtx); 1028 } 1029