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 - 2022 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_tid(sdata, skb, tid); 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 lockdep_assert_held(&sta->ampdu_mlme.mtx); 217 218 if (!txq) 219 return; 220 221 txqi = to_txq_info(txq); 222 223 if (enable) 224 set_bit(IEEE80211_TXQ_AMPDU, &txqi->flags); 225 else 226 clear_bit(IEEE80211_TXQ_AMPDU, &txqi->flags); 227 228 clear_bit(IEEE80211_TXQ_STOP, &txqi->flags); 229 local_bh_disable(); 230 rcu_read_lock(); 231 schedule_and_wake_txq(sta->sdata->local, txqi); 232 rcu_read_unlock(); 233 local_bh_enable(); 234 } 235 236 /* 237 * splice packets from the STA's pending to the local pending, 238 * requires a call to ieee80211_agg_splice_finish later 239 */ 240 static void __acquires(agg_queue) 241 ieee80211_agg_splice_packets(struct ieee80211_sub_if_data *sdata, 242 struct tid_ampdu_tx *tid_tx, u16 tid) 243 { 244 struct ieee80211_local *local = sdata->local; 245 int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)]; 246 unsigned long flags; 247 248 ieee80211_stop_queue_agg(sdata, tid); 249 250 if (WARN(!tid_tx, 251 "TID %d gone but expected when splicing aggregates from the pending queue\n", 252 tid)) 253 return; 254 255 if (!skb_queue_empty(&tid_tx->pending)) { 256 spin_lock_irqsave(&local->queue_stop_reason_lock, flags); 257 /* copy over remaining packets */ 258 skb_queue_splice_tail_init(&tid_tx->pending, 259 &local->pending[queue]); 260 spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); 261 } 262 } 263 264 static void __releases(agg_queue) 265 ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid) 266 { 267 ieee80211_wake_queue_agg(sdata, tid); 268 } 269 270 static void ieee80211_remove_tid_tx(struct sta_info *sta, int tid) 271 { 272 struct tid_ampdu_tx *tid_tx; 273 274 lockdep_assert_held(&sta->ampdu_mlme.mtx); 275 lockdep_assert_held(&sta->lock); 276 277 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 278 279 /* 280 * When we get here, the TX path will not be lockless any more wrt. 281 * aggregation, since the OPERATIONAL bit has long been cleared. 282 * Thus it will block on getting the lock, if it occurs. So if we 283 * stop the queue now, we will not get any more packets, and any 284 * that might be being processed will wait for us here, thereby 285 * guaranteeing that no packets go to the tid_tx pending queue any 286 * more. 287 */ 288 289 ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid); 290 291 /* future packets must not find the tid_tx struct any more */ 292 ieee80211_assign_tid_tx(sta, tid, NULL); 293 294 ieee80211_agg_splice_finish(sta->sdata, tid); 295 296 kfree_rcu(tid_tx, rcu_head); 297 } 298 299 int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, 300 enum ieee80211_agg_stop_reason reason) 301 { 302 struct ieee80211_local *local = sta->local; 303 struct tid_ampdu_tx *tid_tx; 304 struct ieee80211_ampdu_params params = { 305 .sta = &sta->sta, 306 .tid = tid, 307 .buf_size = 0, 308 .amsdu = false, 309 .timeout = 0, 310 .ssn = 0, 311 }; 312 int ret; 313 314 lockdep_assert_held(&sta->ampdu_mlme.mtx); 315 316 switch (reason) { 317 case AGG_STOP_DECLINED: 318 case AGG_STOP_LOCAL_REQUEST: 319 case AGG_STOP_PEER_REQUEST: 320 params.action = IEEE80211_AMPDU_TX_STOP_CONT; 321 break; 322 case AGG_STOP_DESTROY_STA: 323 params.action = IEEE80211_AMPDU_TX_STOP_FLUSH; 324 break; 325 default: 326 WARN_ON_ONCE(1); 327 return -EINVAL; 328 } 329 330 spin_lock_bh(&sta->lock); 331 332 /* free struct pending for start, if present */ 333 tid_tx = sta->ampdu_mlme.tid_start_tx[tid]; 334 kfree(tid_tx); 335 sta->ampdu_mlme.tid_start_tx[tid] = NULL; 336 337 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 338 if (!tid_tx) { 339 spin_unlock_bh(&sta->lock); 340 return -ENOENT; 341 } 342 343 /* 344 * if we're already stopping ignore any new requests to stop 345 * unless we're destroying it in which case notify the driver 346 */ 347 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { 348 spin_unlock_bh(&sta->lock); 349 if (reason != AGG_STOP_DESTROY_STA) 350 return -EALREADY; 351 params.action = IEEE80211_AMPDU_TX_STOP_FLUSH_CONT; 352 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 353 WARN_ON_ONCE(ret); 354 return 0; 355 } 356 357 if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) { 358 /* not even started yet! */ 359 ieee80211_assign_tid_tx(sta, tid, NULL); 360 spin_unlock_bh(&sta->lock); 361 kfree_rcu(tid_tx, rcu_head); 362 return 0; 363 } 364 365 set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state); 366 367 ieee80211_agg_stop_txq(sta, tid); 368 369 spin_unlock_bh(&sta->lock); 370 371 ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n", 372 sta->sta.addr, tid); 373 374 del_timer_sync(&tid_tx->addba_resp_timer); 375 del_timer_sync(&tid_tx->session_timer); 376 377 /* 378 * After this packets are no longer handed right through 379 * to the driver but are put onto tid_tx->pending instead, 380 * with locking to ensure proper access. 381 */ 382 clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state); 383 384 /* 385 * There might be a few packets being processed right now (on 386 * another CPU) that have already gotten past the aggregation 387 * check when it was still OPERATIONAL and consequently have 388 * IEEE80211_TX_CTL_AMPDU set. In that case, this code might 389 * call into the driver at the same time or even before the 390 * TX paths calls into it, which could confuse the driver. 391 * 392 * Wait for all currently running TX paths to finish before 393 * telling the driver. New packets will not go through since 394 * the aggregation session is no longer OPERATIONAL. 395 */ 396 if (!local->in_reconfig) 397 synchronize_net(); 398 399 tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ? 400 WLAN_BACK_RECIPIENT : 401 WLAN_BACK_INITIATOR; 402 tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST; 403 404 ret = drv_ampdu_action(local, sta->sdata, ¶ms); 405 406 /* HW shall not deny going back to legacy */ 407 if (WARN_ON(ret)) { 408 /* 409 * We may have pending packets get stuck in this case... 410 * Not bothering with a workaround for now. 411 */ 412 } 413 414 /* 415 * In the case of AGG_STOP_DESTROY_STA, the driver won't 416 * necessarily call ieee80211_stop_tx_ba_cb(), so this may 417 * seem like we can leave the tid_tx data pending forever. 418 * This is true, in a way, but "forever" is only until the 419 * station struct is actually destroyed. In the meantime, 420 * leaving it around ensures that we don't transmit packets 421 * to the driver on this TID which might confuse it. 422 */ 423 424 return 0; 425 } 426 427 /* 428 * After sending add Block Ack request we activated a timer until 429 * add Block Ack response will arrive from the recipient. 430 * If this timer expires sta_addba_resp_timer_expired will be executed. 431 */ 432 static void sta_addba_resp_timer_expired(struct timer_list *t) 433 { 434 struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, addba_resp_timer); 435 struct sta_info *sta = tid_tx->sta; 436 u8 tid = tid_tx->tid; 437 438 /* check if the TID waits for addBA response */ 439 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { 440 ht_dbg(sta->sdata, 441 "timer expired on %pM tid %d not expecting addBA response\n", 442 sta->sta.addr, tid); 443 return; 444 } 445 446 ht_dbg(sta->sdata, "addBA response timer expired on %pM tid %d\n", 447 sta->sta.addr, tid); 448 449 ieee80211_stop_tx_ba_session(&sta->sta, tid); 450 } 451 452 static void ieee80211_send_addba_with_timeout(struct sta_info *sta, 453 struct tid_ampdu_tx *tid_tx) 454 { 455 struct ieee80211_sub_if_data *sdata = sta->sdata; 456 struct ieee80211_local *local = sta->local; 457 u8 tid = tid_tx->tid; 458 u16 buf_size; 459 460 /* activate the timer for the recipient's addBA response */ 461 mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL); 462 ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n", 463 sta->sta.addr, tid); 464 465 spin_lock_bh(&sta->lock); 466 sta->ampdu_mlme.last_addba_req_time[tid] = jiffies; 467 sta->ampdu_mlme.addba_req_num[tid]++; 468 spin_unlock_bh(&sta->lock); 469 470 if (sta->sta.deflink.he_cap.has_he) { 471 buf_size = local->hw.max_tx_aggregation_subframes; 472 } else { 473 /* 474 * We really should use what the driver told us it will 475 * transmit as the maximum, but certain APs (e.g. the 476 * LinkSys WRT120N with FW v1.0.07 build 002 Jun 18 2012) 477 * will crash when we use a lower number. 478 */ 479 buf_size = IEEE80211_MAX_AMPDU_BUF_HT; 480 } 481 482 /* send AddBA request */ 483 ieee80211_send_addba_request(sdata, sta->sta.addr, tid, 484 tid_tx->dialog_token, tid_tx->ssn, 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 tid_tx->ssn = params.ssn; 527 if (ret == IEEE80211_AMPDU_TX_START_DELAY_ADDBA) { 528 return; 529 } else if (ret == IEEE80211_AMPDU_TX_START_IMMEDIATE) { 530 /* 531 * We didn't send the request yet, so don't need to check 532 * here if we already got a response, just mark as driver 533 * ready immediately. 534 */ 535 set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state); 536 } else if (ret) { 537 ht_dbg(sdata, 538 "BA request denied - HW unavailable for %pM tid %d\n", 539 sta->sta.addr, tid); 540 spin_lock_bh(&sta->lock); 541 ieee80211_agg_splice_packets(sdata, tid_tx, tid); 542 ieee80211_assign_tid_tx(sta, tid, NULL); 543 ieee80211_agg_splice_finish(sdata, tid); 544 spin_unlock_bh(&sta->lock); 545 546 ieee80211_agg_start_txq(sta, tid, false); 547 548 kfree_rcu(tid_tx, rcu_head); 549 return; 550 } 551 552 ieee80211_send_addba_with_timeout(sta, tid_tx); 553 } 554 555 /* 556 * After accepting the AddBA Response we activated a timer, 557 * resetting it after each frame that we send. 558 */ 559 static void sta_tx_agg_session_timer_expired(struct timer_list *t) 560 { 561 struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, session_timer); 562 struct sta_info *sta = tid_tx->sta; 563 u8 tid = tid_tx->tid; 564 unsigned long timeout; 565 566 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { 567 return; 568 } 569 570 timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout); 571 if (time_is_after_jiffies(timeout)) { 572 mod_timer(&tid_tx->session_timer, timeout); 573 return; 574 } 575 576 ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n", 577 sta->sta.addr, tid); 578 579 ieee80211_stop_tx_ba_session(&sta->sta, tid); 580 } 581 582 int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid, 583 u16 timeout) 584 { 585 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 586 struct ieee80211_sub_if_data *sdata = sta->sdata; 587 struct ieee80211_local *local = sdata->local; 588 struct tid_ampdu_tx *tid_tx; 589 int ret = 0; 590 591 trace_api_start_tx_ba_session(pubsta, tid); 592 593 if (WARN(sta->reserved_tid == tid, 594 "Requested to start BA session on reserved tid=%d", tid)) 595 return -EINVAL; 596 597 if (!pubsta->deflink.ht_cap.ht_supported && 598 sta->sdata->vif.bss_conf.chandef.chan->band != NL80211_BAND_6GHZ) 599 return -EINVAL; 600 601 if (WARN_ON_ONCE(!local->ops->ampdu_action)) 602 return -EINVAL; 603 604 if ((tid >= IEEE80211_NUM_TIDS) || 605 !ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) || 606 ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW)) 607 return -EINVAL; 608 609 if (WARN_ON(tid >= IEEE80211_FIRST_TSPEC_TSID)) 610 return -EINVAL; 611 612 ht_dbg(sdata, "Open BA session requested for %pM tid %u\n", 613 pubsta->addr, tid); 614 615 if (sdata->vif.type != NL80211_IFTYPE_STATION && 616 sdata->vif.type != NL80211_IFTYPE_MESH_POINT && 617 sdata->vif.type != NL80211_IFTYPE_AP_VLAN && 618 sdata->vif.type != NL80211_IFTYPE_AP && 619 sdata->vif.type != NL80211_IFTYPE_ADHOC) 620 return -EINVAL; 621 622 if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { 623 ht_dbg(sdata, 624 "BA sessions blocked - Denying BA session request %pM tid %d\n", 625 sta->sta.addr, tid); 626 return -EINVAL; 627 } 628 629 if (test_sta_flag(sta, WLAN_STA_MFP) && 630 !test_sta_flag(sta, WLAN_STA_AUTHORIZED)) { 631 ht_dbg(sdata, 632 "MFP STA not authorized - deny BA session request %pM tid %d\n", 633 sta->sta.addr, tid); 634 return -EINVAL; 635 } 636 637 /* 638 * 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a 639 * member of an IBSS, and has no other existing Block Ack agreement 640 * with the recipient STA, then the initiating STA shall transmit a 641 * Probe Request frame to the recipient STA and shall not transmit an 642 * ADDBA Request frame unless it receives a Probe Response frame 643 * from the recipient within dot11ADDBAFailureTimeout. 644 * 645 * The probe request mechanism for ADDBA is currently not implemented, 646 * but we only build up Block Ack session with HT STAs. This information 647 * is set when we receive a bss info from a probe response or a beacon. 648 */ 649 if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC && 650 !sta->sta.deflink.ht_cap.ht_supported) { 651 ht_dbg(sdata, 652 "BA request denied - IBSS STA %pM does not advertise HT support\n", 653 pubsta->addr); 654 return -EINVAL; 655 } 656 657 spin_lock_bh(&sta->lock); 658 659 /* we have tried too many times, receiver does not want A-MPDU */ 660 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) { 661 ret = -EBUSY; 662 goto err_unlock_sta; 663 } 664 665 /* 666 * if we have tried more than HT_AGG_BURST_RETRIES times we 667 * will spread our requests in time to avoid stalling connection 668 * for too long 669 */ 670 if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES && 671 time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] + 672 HT_AGG_RETRIES_PERIOD)) { 673 ht_dbg(sdata, 674 "BA request denied - %d failed requests on %pM tid %u\n", 675 sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid); 676 ret = -EBUSY; 677 goto err_unlock_sta; 678 } 679 680 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 681 /* check if the TID is not in aggregation flow already */ 682 if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) { 683 ht_dbg(sdata, 684 "BA request denied - session is not idle on %pM tid %u\n", 685 sta->sta.addr, tid); 686 ret = -EAGAIN; 687 goto err_unlock_sta; 688 } 689 690 /* prepare A-MPDU MLME for Tx aggregation */ 691 tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC); 692 if (!tid_tx) { 693 ret = -ENOMEM; 694 goto err_unlock_sta; 695 } 696 697 skb_queue_head_init(&tid_tx->pending); 698 __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state); 699 700 tid_tx->timeout = timeout; 701 tid_tx->sta = sta; 702 tid_tx->tid = tid; 703 704 /* response timer */ 705 timer_setup(&tid_tx->addba_resp_timer, sta_addba_resp_timer_expired, 0); 706 707 /* tx timer */ 708 timer_setup(&tid_tx->session_timer, 709 sta_tx_agg_session_timer_expired, TIMER_DEFERRABLE); 710 711 /* assign a dialog token */ 712 sta->ampdu_mlme.dialog_token_allocator++; 713 tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator; 714 715 /* 716 * Finally, assign it to the start array; the work item will 717 * collect it and move it to the normal array. 718 */ 719 sta->ampdu_mlme.tid_start_tx[tid] = tid_tx; 720 721 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 722 723 /* this flow continues off the work */ 724 err_unlock_sta: 725 spin_unlock_bh(&sta->lock); 726 return ret; 727 } 728 EXPORT_SYMBOL(ieee80211_start_tx_ba_session); 729 730 static void ieee80211_agg_tx_operational(struct ieee80211_local *local, 731 struct sta_info *sta, u16 tid) 732 { 733 struct tid_ampdu_tx *tid_tx; 734 struct ieee80211_ampdu_params params = { 735 .sta = &sta->sta, 736 .action = IEEE80211_AMPDU_TX_OPERATIONAL, 737 .tid = tid, 738 .timeout = 0, 739 .ssn = 0, 740 }; 741 742 lockdep_assert_held(&sta->ampdu_mlme.mtx); 743 744 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 745 params.buf_size = tid_tx->buf_size; 746 params.amsdu = tid_tx->amsdu; 747 748 ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n", 749 sta->sta.addr, tid); 750 751 drv_ampdu_action(local, sta->sdata, ¶ms); 752 753 /* 754 * synchronize with TX path, while splicing the TX path 755 * should block so it won't put more packets onto pending. 756 */ 757 spin_lock_bh(&sta->lock); 758 759 ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid); 760 /* 761 * Now mark as operational. This will be visible 762 * in the TX path, and lets it go lock-free in 763 * the common case. 764 */ 765 set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state); 766 ieee80211_agg_splice_finish(sta->sdata, tid); 767 768 spin_unlock_bh(&sta->lock); 769 770 ieee80211_agg_start_txq(sta, tid, true); 771 } 772 773 void ieee80211_start_tx_ba_cb(struct sta_info *sta, int tid, 774 struct tid_ampdu_tx *tid_tx) 775 { 776 struct ieee80211_sub_if_data *sdata = sta->sdata; 777 struct ieee80211_local *local = sdata->local; 778 779 if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))) 780 return; 781 782 if (!test_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state)) { 783 ieee80211_send_addba_with_timeout(sta, tid_tx); 784 /* RESPONSE_RECEIVED state whould trigger the flow again */ 785 return; 786 } 787 788 if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) 789 ieee80211_agg_tx_operational(local, sta, tid); 790 } 791 792 static struct tid_ampdu_tx * 793 ieee80211_lookup_tid_tx(struct ieee80211_sub_if_data *sdata, 794 const u8 *ra, u16 tid, struct sta_info **sta) 795 { 796 struct tid_ampdu_tx *tid_tx; 797 798 if (tid >= IEEE80211_NUM_TIDS) { 799 ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n", 800 tid, IEEE80211_NUM_TIDS); 801 return NULL; 802 } 803 804 *sta = sta_info_get_bss(sdata, ra); 805 if (!*sta) { 806 ht_dbg(sdata, "Could not find station: %pM\n", ra); 807 return NULL; 808 } 809 810 tid_tx = rcu_dereference((*sta)->ampdu_mlme.tid_tx[tid]); 811 812 if (WARN_ON(!tid_tx)) 813 ht_dbg(sdata, "addBA was not requested!\n"); 814 815 return tid_tx; 816 } 817 818 void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif, 819 const u8 *ra, u16 tid) 820 { 821 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 822 struct ieee80211_local *local = sdata->local; 823 struct sta_info *sta; 824 struct tid_ampdu_tx *tid_tx; 825 826 trace_api_start_tx_ba_cb(sdata, ra, tid); 827 828 rcu_read_lock(); 829 tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta); 830 if (!tid_tx) 831 goto out; 832 833 set_bit(HT_AGG_STATE_START_CB, &tid_tx->state); 834 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 835 out: 836 rcu_read_unlock(); 837 } 838 EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe); 839 840 int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, 841 enum ieee80211_agg_stop_reason reason) 842 { 843 int ret; 844 845 mutex_lock(&sta->ampdu_mlme.mtx); 846 847 ret = ___ieee80211_stop_tx_ba_session(sta, tid, reason); 848 849 mutex_unlock(&sta->ampdu_mlme.mtx); 850 851 return ret; 852 } 853 854 int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid) 855 { 856 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 857 struct ieee80211_sub_if_data *sdata = sta->sdata; 858 struct ieee80211_local *local = sdata->local; 859 struct tid_ampdu_tx *tid_tx; 860 int ret = 0; 861 862 trace_api_stop_tx_ba_session(pubsta, tid); 863 864 if (!local->ops->ampdu_action) 865 return -EINVAL; 866 867 if (tid >= IEEE80211_NUM_TIDS) 868 return -EINVAL; 869 870 spin_lock_bh(&sta->lock); 871 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 872 873 if (!tid_tx) { 874 ret = -ENOENT; 875 goto unlock; 876 } 877 878 WARN(sta->reserved_tid == tid, 879 "Requested to stop BA session on reserved tid=%d", tid); 880 881 if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { 882 /* already in progress stopping it */ 883 ret = 0; 884 goto unlock; 885 } 886 887 set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state); 888 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 889 890 unlock: 891 spin_unlock_bh(&sta->lock); 892 return ret; 893 } 894 EXPORT_SYMBOL(ieee80211_stop_tx_ba_session); 895 896 void ieee80211_stop_tx_ba_cb(struct sta_info *sta, int tid, 897 struct tid_ampdu_tx *tid_tx) 898 { 899 struct ieee80211_sub_if_data *sdata = sta->sdata; 900 bool send_delba = false; 901 bool start_txq = false; 902 903 ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n", 904 sta->sta.addr, tid); 905 906 spin_lock_bh(&sta->lock); 907 908 if (!test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { 909 ht_dbg(sdata, 910 "unexpected callback to A-MPDU stop for %pM tid %d\n", 911 sta->sta.addr, tid); 912 goto unlock_sta; 913 } 914 915 if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop) 916 send_delba = true; 917 918 ieee80211_remove_tid_tx(sta, tid); 919 start_txq = true; 920 921 unlock_sta: 922 spin_unlock_bh(&sta->lock); 923 924 if (start_txq) 925 ieee80211_agg_start_txq(sta, tid, false); 926 927 if (send_delba) 928 ieee80211_send_delba(sdata, sta->sta.addr, tid, 929 WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE); 930 } 931 932 void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif, 933 const u8 *ra, u16 tid) 934 { 935 struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); 936 struct ieee80211_local *local = sdata->local; 937 struct sta_info *sta; 938 struct tid_ampdu_tx *tid_tx; 939 940 trace_api_stop_tx_ba_cb(sdata, ra, tid); 941 942 rcu_read_lock(); 943 tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta); 944 if (!tid_tx) 945 goto out; 946 947 set_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state); 948 ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); 949 out: 950 rcu_read_unlock(); 951 } 952 EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe); 953 954 955 void ieee80211_process_addba_resp(struct ieee80211_local *local, 956 struct sta_info *sta, 957 struct ieee80211_mgmt *mgmt, 958 size_t len) 959 { 960 struct tid_ampdu_tx *tid_tx; 961 struct ieee80211_txq *txq; 962 u16 capab, tid, buf_size; 963 bool amsdu; 964 965 capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab); 966 amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK; 967 tid = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_TID_MASK); 968 buf_size = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK); 969 buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes); 970 971 txq = sta->sta.txq[tid]; 972 if (!amsdu && txq) 973 set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags); 974 975 mutex_lock(&sta->ampdu_mlme.mtx); 976 977 tid_tx = rcu_dereference_protected_tid_tx(sta, tid); 978 if (!tid_tx) 979 goto out; 980 981 if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) { 982 ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n", 983 sta->sta.addr, tid); 984 goto out; 985 } 986 987 del_timer_sync(&tid_tx->addba_resp_timer); 988 989 ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n", 990 sta->sta.addr, tid); 991 992 /* 993 * addba_resp_timer may have fired before we got here, and 994 * caused WANT_STOP to be set. If the stop then was already 995 * processed further, STOPPING might be set. 996 */ 997 if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) || 998 test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { 999 ht_dbg(sta->sdata, 1000 "got addBA resp for %pM tid %d but we already gave up\n", 1001 sta->sta.addr, tid); 1002 goto out; 1003 } 1004 1005 /* 1006 * IEEE 802.11-2007 7.3.1.14: 1007 * In an ADDBA Response frame, when the Status Code field 1008 * is set to 0, the Buffer Size subfield is set to a value 1009 * of at least 1. 1010 */ 1011 if (le16_to_cpu(mgmt->u.action.u.addba_resp.status) 1012 == WLAN_STATUS_SUCCESS && buf_size) { 1013 if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED, 1014 &tid_tx->state)) { 1015 /* ignore duplicate response */ 1016 goto out; 1017 } 1018 1019 tid_tx->buf_size = buf_size; 1020 tid_tx->amsdu = amsdu; 1021 1022 if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)) 1023 ieee80211_agg_tx_operational(local, sta, tid); 1024 1025 sta->ampdu_mlme.addba_req_num[tid] = 0; 1026 1027 tid_tx->timeout = 1028 le16_to_cpu(mgmt->u.action.u.addba_resp.timeout); 1029 1030 if (tid_tx->timeout) { 1031 mod_timer(&tid_tx->session_timer, 1032 TU_TO_EXP_TIME(tid_tx->timeout)); 1033 tid_tx->last_tx = jiffies; 1034 } 1035 1036 } else { 1037 ___ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED); 1038 } 1039 1040 out: 1041 mutex_unlock(&sta->ampdu_mlme.mtx); 1042 } 1043