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v4.10.11
 
   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 2007-2010, Intel Corporation
  10 * Copyright(c) 2015 Intel Deutschland GmbH
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License version 2 as
  14 * published by the Free Software Foundation.
  15 */
  16
  17#include <linux/ieee80211.h>
  18#include <linux/slab.h>
  19#include <linux/export.h>
  20#include <net/mac80211.h>
  21#include "ieee80211_i.h"
  22#include "driver-ops.h"
  23#include "wme.h"
  24
  25/**
  26 * DOC: TX A-MPDU aggregation
  27 *
  28 * Aggregation on the TX side requires setting the hardware flag
  29 * %IEEE80211_HW_AMPDU_AGGREGATION. The driver will then be handed
  30 * packets with a flag indicating A-MPDU aggregation. The driver
  31 * or device is responsible for actually aggregating the frames,
  32 * as well as deciding how many and which to aggregate.
  33 *
  34 * When TX aggregation is started by some subsystem (usually the rate
  35 * control algorithm would be appropriate) by calling the
  36 * ieee80211_start_tx_ba_session() function, the driver will be
  37 * notified via its @ampdu_action function, with the
  38 * %IEEE80211_AMPDU_TX_START action.
  39 *
  40 * In response to that, the driver is later required to call the
  41 * ieee80211_start_tx_ba_cb_irqsafe() function, which will really
  42 * start the aggregation session after the peer has also responded.
  43 * If the peer responds negatively, the session will be stopped
  44 * again right away. Note that it is possible for the aggregation
  45 * session to be stopped before the driver has indicated that it
  46 * is done setting it up, in which case it must not indicate the
  47 * setup completion.
  48 *
  49 * Also note that, since we also need to wait for a response from
  50 * the peer, the driver is notified of the completion of the
  51 * handshake by the %IEEE80211_AMPDU_TX_OPERATIONAL action to the
  52 * @ampdu_action callback.
  53 *
  54 * Similarly, when the aggregation session is stopped by the peer
  55 * or something calling ieee80211_stop_tx_ba_session(), the driver's
  56 * @ampdu_action function will be called with the action
  57 * %IEEE80211_AMPDU_TX_STOP. In this case, the call must not fail,
  58 * and the driver must later call ieee80211_stop_tx_ba_cb_irqsafe().
  59 * Note that the sta can get destroyed before the BA tear down is
  60 * complete.
  61 */
  62
  63static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
  64					 const u8 *da, u16 tid,
  65					 u8 dialog_token, u16 start_seq_num,
  66					 u16 agg_size, u16 timeout)
  67{
 
  68	struct ieee80211_local *local = sdata->local;
  69	struct sk_buff *skb;
  70	struct ieee80211_mgmt *mgmt;
  71	u16 capab;
  72
  73	skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
  74
 
  75	if (!skb)
  76		return;
  77
  78	skb_reserve(skb, local->hw.extra_tx_headroom);
  79	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
  80	memset(mgmt, 0, 24);
  81	memcpy(mgmt->da, da, ETH_ALEN);
  82	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
  83	if (sdata->vif.type == NL80211_IFTYPE_AP ||
  84	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
  85	    sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
  86		memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
  87	else if (sdata->vif.type == NL80211_IFTYPE_STATION)
  88		memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
  89	else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
  90		memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
  91
  92	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
  93					  IEEE80211_STYPE_ACTION);
  94
  95	skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
  96
  97	mgmt->u.action.category = WLAN_CATEGORY_BACK;
  98	mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
  99
 100	mgmt->u.action.u.addba_req.dialog_token = dialog_token;
 101	capab = (u16)(1 << 0);		/* bit 0 A-MSDU support */
 102	capab |= (u16)(1 << 1);		/* bit 1 aggregation policy */
 103	capab |= (u16)(tid << 2); 	/* bit 5:2 TID number */
 104	capab |= (u16)(agg_size << 6);	/* bit 15:6 max size of aggergation */
 105
 106	mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
 107
 108	mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
 109	mgmt->u.action.u.addba_req.start_seq_num =
 110					cpu_to_le16(start_seq_num << 4);
 111
 112	ieee80211_tx_skb(sdata, skb);
 
 
 
 113}
 114
 115void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn)
 116{
 117	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 118	struct ieee80211_local *local = sdata->local;
 119	struct sk_buff *skb;
 120	struct ieee80211_bar *bar;
 121	u16 bar_control = 0;
 122
 123	skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
 124	if (!skb)
 125		return;
 126
 127	skb_reserve(skb, local->hw.extra_tx_headroom);
 128	bar = (struct ieee80211_bar *)skb_put(skb, sizeof(*bar));
 129	memset(bar, 0, sizeof(*bar));
 130	bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
 131					 IEEE80211_STYPE_BACK_REQ);
 132	memcpy(bar->ra, ra, ETH_ALEN);
 133	memcpy(bar->ta, sdata->vif.addr, ETH_ALEN);
 134	bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
 135	bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
 136	bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT);
 137	bar->control = cpu_to_le16(bar_control);
 138	bar->start_seq_num = cpu_to_le16(ssn);
 139
 140	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
 141					IEEE80211_TX_CTL_REQ_TX_STATUS;
 142	ieee80211_tx_skb_tid(sdata, skb, tid);
 143}
 144EXPORT_SYMBOL(ieee80211_send_bar);
 145
 146void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
 147			     struct tid_ampdu_tx *tid_tx)
 148{
 149	lockdep_assert_held(&sta->ampdu_mlme.mtx);
 150	lockdep_assert_held(&sta->lock);
 151	rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
 152}
 153
 154/*
 155 * When multiple aggregation sessions on multiple stations
 156 * are being created/destroyed simultaneously, we need to
 157 * refcount the global queue stop caused by that in order
 158 * to not get into a situation where one of the aggregation
 159 * setup or teardown re-enables queues before the other is
 160 * ready to handle that.
 161 *
 162 * These two functions take care of this issue by keeping
 163 * a global "agg_queue_stop" refcount.
 164 */
 165static void __acquires(agg_queue)
 166ieee80211_stop_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
 167{
 168	int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
 169
 170	/* we do refcounting here, so don't use the queue reason refcounting */
 171
 172	if (atomic_inc_return(&sdata->local->agg_queue_stop[queue]) == 1)
 173		ieee80211_stop_queue_by_reason(
 174			&sdata->local->hw, queue,
 175			IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
 176			false);
 177	__acquire(agg_queue);
 178}
 179
 180static void __releases(agg_queue)
 181ieee80211_wake_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
 182{
 183	int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
 184
 185	if (atomic_dec_return(&sdata->local->agg_queue_stop[queue]) == 0)
 186		ieee80211_wake_queue_by_reason(
 187			&sdata->local->hw, queue,
 188			IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
 189			false);
 190	__release(agg_queue);
 191}
 192
 193static void
 194ieee80211_agg_stop_txq(struct sta_info *sta, int tid)
 195{
 196	struct ieee80211_txq *txq = sta->sta.txq[tid];
 197	struct ieee80211_sub_if_data *sdata;
 198	struct fq *fq;
 199	struct txq_info *txqi;
 200
 201	if (!txq)
 202		return;
 203
 204	txqi = to_txq_info(txq);
 205	sdata = vif_to_sdata(txq->vif);
 206	fq = &sdata->local->fq;
 207
 208	/* Lock here to protect against further seqno updates on dequeue */
 209	spin_lock_bh(&fq->lock);
 210	set_bit(IEEE80211_TXQ_STOP, &txqi->flags);
 211	spin_unlock_bh(&fq->lock);
 212}
 213
 214static void
 215ieee80211_agg_start_txq(struct sta_info *sta, int tid, bool enable)
 216{
 217	struct ieee80211_txq *txq = sta->sta.txq[tid];
 218	struct txq_info *txqi;
 219
 
 
 220	if (!txq)
 221		return;
 222
 223	txqi = to_txq_info(txq);
 224
 225	if (enable)
 226		set_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
 227	else
 228		clear_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
 229
 230	clear_bit(IEEE80211_TXQ_STOP, &txqi->flags);
 231	drv_wake_tx_queue(sta->sdata->local, txqi);
 
 
 
 
 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 */
 238static void __acquires(agg_queue)
 239ieee80211_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
 262static void __releases(agg_queue)
 263ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid)
 264{
 265	ieee80211_wake_queue_agg(sdata, tid);
 266}
 267
 268static 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
 298int ___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	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 332	if (!tid_tx) {
 333		spin_unlock_bh(&sta->lock);
 334		return -ENOENT;
 335	}
 336
 337	/*
 338	 * if we're already stopping ignore any new requests to stop
 339	 * unless we're destroying it in which case notify the driver
 340	 */
 341	if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
 342		spin_unlock_bh(&sta->lock);
 343		if (reason != AGG_STOP_DESTROY_STA)
 344			return -EALREADY;
 345		params.action = IEEE80211_AMPDU_TX_STOP_FLUSH_CONT;
 346		ret = drv_ampdu_action(local, sta->sdata, &params);
 347		WARN_ON_ONCE(ret);
 348		return 0;
 349	}
 350
 351	if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
 352		/* not even started yet! */
 353		ieee80211_assign_tid_tx(sta, tid, NULL);
 354		spin_unlock_bh(&sta->lock);
 355		kfree_rcu(tid_tx, rcu_head);
 356		return 0;
 357	}
 358
 359	set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
 360
 
 
 361	spin_unlock_bh(&sta->lock);
 362
 363	ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n",
 364	       sta->sta.addr, tid);
 365
 366	del_timer_sync(&tid_tx->addba_resp_timer);
 367	del_timer_sync(&tid_tx->session_timer);
 368
 369	/*
 370	 * After this packets are no longer handed right through
 371	 * to the driver but are put onto tid_tx->pending instead,
 372	 * with locking to ensure proper access.
 373	 */
 374	clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
 375
 376	/*
 377	 * There might be a few packets being processed right now (on
 378	 * another CPU) that have already gotten past the aggregation
 379	 * check when it was still OPERATIONAL and consequently have
 380	 * IEEE80211_TX_CTL_AMPDU set. In that case, this code might
 381	 * call into the driver at the same time or even before the
 382	 * TX paths calls into it, which could confuse the driver.
 383	 *
 384	 * Wait for all currently running TX paths to finish before
 385	 * telling the driver. New packets will not go through since
 386	 * the aggregation session is no longer OPERATIONAL.
 387	 */
 388	synchronize_net();
 
 389
 390	tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ?
 391					WLAN_BACK_RECIPIENT :
 392					WLAN_BACK_INITIATOR;
 393	tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST;
 394
 395	ret = drv_ampdu_action(local, sta->sdata, &params);
 396
 397	/* HW shall not deny going back to legacy */
 398	if (WARN_ON(ret)) {
 399		/*
 400		 * We may have pending packets get stuck in this case...
 401		 * Not bothering with a workaround for now.
 402		 */
 403	}
 404
 405	/*
 406	 * In the case of AGG_STOP_DESTROY_STA, the driver won't
 407	 * necessarily call ieee80211_stop_tx_ba_cb(), so this may
 408	 * seem like we can leave the tid_tx data pending forever.
 409	 * This is true, in a way, but "forever" is only until the
 410	 * station struct is actually destroyed. In the meantime,
 411	 * leaving it around ensures that we don't transmit packets
 412	 * to the driver on this TID which might confuse it.
 413	 */
 414
 415	return 0;
 416}
 417
 418/*
 419 * After sending add Block Ack request we activated a timer until
 420 * add Block Ack response will arrive from the recipient.
 421 * If this timer expires sta_addba_resp_timer_expired will be executed.
 422 */
 423static void sta_addba_resp_timer_expired(unsigned long data)
 424{
 425	/* not an elegant detour, but there is no choice as the timer passes
 426	 * only one argument, and both sta_info and TID are needed, so init
 427	 * flow in sta_info_create gives the TID as data, while the timer_to_id
 428	 * array gives the sta through container_of */
 429	u16 tid = *(u8 *)data;
 430	struct sta_info *sta = container_of((void *)data,
 431		struct sta_info, timer_to_tid[tid]);
 432	struct tid_ampdu_tx *tid_tx;
 433
 434	/* check if the TID waits for addBA response */
 435	rcu_read_lock();
 436	tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 437	if (!tid_tx ||
 438	    test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
 439		rcu_read_unlock();
 440		ht_dbg(sta->sdata,
 441		       "timer expired on %pM tid %d but we are not (or no longer) expecting addBA response there\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	rcu_read_unlock();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 451}
 452
 453void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
 454{
 455	struct tid_ampdu_tx *tid_tx;
 456	struct ieee80211_local *local = sta->local;
 457	struct ieee80211_sub_if_data *sdata = sta->sdata;
 458	struct ieee80211_ampdu_params params = {
 459		.sta = &sta->sta,
 460		.action = IEEE80211_AMPDU_TX_START,
 461		.tid = tid,
 462		.buf_size = 0,
 463		.amsdu = false,
 464		.timeout = 0,
 465	};
 466	int ret;
 467
 468	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 469
 470	/*
 471	 * Start queuing up packets for this aggregation session.
 472	 * We're going to release them once the driver is OK with
 473	 * that.
 474	 */
 475	clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
 476
 477	ieee80211_agg_stop_txq(sta, tid);
 478
 479	/*
 480	 * Make sure no packets are being processed. This ensures that
 481	 * we have a valid starting sequence number and that in-flight
 482	 * packets have been flushed out and no packets for this TID
 483	 * will go into the driver during the ampdu_action call.
 484	 */
 485	synchronize_net();
 486
 487	params.ssn = sta->tid_seq[tid] >> 4;
 488	ret = drv_ampdu_action(local, sdata, &params);
 489	if (ret) {
 
 
 
 
 
 
 
 
 
 
 490		ht_dbg(sdata,
 491		       "BA request denied - HW unavailable for %pM tid %d\n",
 492		       sta->sta.addr, tid);
 493		spin_lock_bh(&sta->lock);
 494		ieee80211_agg_splice_packets(sdata, tid_tx, tid);
 495		ieee80211_assign_tid_tx(sta, tid, NULL);
 496		ieee80211_agg_splice_finish(sdata, tid);
 497		spin_unlock_bh(&sta->lock);
 498
 499		ieee80211_agg_start_txq(sta, tid, false);
 500
 501		kfree_rcu(tid_tx, rcu_head);
 502		return;
 503	}
 504
 505	/* activate the timer for the recipient's addBA response */
 506	mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
 507	ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n",
 508	       sta->sta.addr, tid);
 509
 510	spin_lock_bh(&sta->lock);
 511	sta->ampdu_mlme.last_addba_req_time[tid] = jiffies;
 512	sta->ampdu_mlme.addba_req_num[tid]++;
 513	spin_unlock_bh(&sta->lock);
 
 514
 515	/* send AddBA request */
 516	ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
 517				     tid_tx->dialog_token, params.ssn,
 518				     IEEE80211_MAX_AMPDU_BUF,
 519				     tid_tx->timeout);
 
 
 
 520}
 
 521
 522/*
 523 * After accepting the AddBA Response we activated a timer,
 524 * resetting it after each frame that we send.
 525 */
 526static void sta_tx_agg_session_timer_expired(unsigned long data)
 527{
 528	/* not an elegant detour, but there is no choice as the timer passes
 529	 * only one argument, and various sta_info are needed here, so init
 530	 * flow in sta_info_create gives the TID as data, while the timer_to_id
 531	 * array gives the sta through container_of */
 532	u8 *ptid = (u8 *)data;
 533	u8 *timer_to_id = ptid - *ptid;
 534	struct sta_info *sta = container_of(timer_to_id, struct sta_info,
 535					 timer_to_tid[0]);
 536	struct tid_ampdu_tx *tid_tx;
 537	unsigned long timeout;
 538
 539	rcu_read_lock();
 540	tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[*ptid]);
 541	if (!tid_tx || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
 542		rcu_read_unlock();
 543		return;
 544	}
 545
 546	timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout);
 547	if (time_is_after_jiffies(timeout)) {
 548		mod_timer(&tid_tx->session_timer, timeout);
 549		rcu_read_unlock();
 550		return;
 551	}
 552
 553	rcu_read_unlock();
 554
 555	ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n",
 556	       sta->sta.addr, (u16)*ptid);
 557
 558	ieee80211_stop_tx_ba_session(&sta->sta, *ptid);
 559}
 560
 561int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
 562				  u16 timeout)
 563{
 564	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 565	struct ieee80211_sub_if_data *sdata = sta->sdata;
 566	struct ieee80211_local *local = sdata->local;
 567	struct tid_ampdu_tx *tid_tx;
 568	int ret = 0;
 569
 570	trace_api_start_tx_ba_session(pubsta, tid);
 571
 572	if (WARN(sta->reserved_tid == tid,
 573		 "Requested to start BA session on reserved tid=%d", tid))
 574		return -EINVAL;
 575
 576	if (!pubsta->ht_cap.ht_supported)
 
 
 
 577		return -EINVAL;
 578
 579	if (WARN_ON_ONCE(!local->ops->ampdu_action))
 580		return -EINVAL;
 581
 582	if ((tid >= IEEE80211_NUM_TIDS) ||
 583	    !ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) ||
 584	    ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW))
 585		return -EINVAL;
 586
 587	if (WARN_ON(tid >= IEEE80211_FIRST_TSPEC_TSID))
 588		return -EINVAL;
 589
 590	ht_dbg(sdata, "Open BA session requested for %pM tid %u\n",
 591	       pubsta->addr, tid);
 592
 593	if (sdata->vif.type != NL80211_IFTYPE_STATION &&
 594	    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
 595	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
 596	    sdata->vif.type != NL80211_IFTYPE_AP &&
 597	    sdata->vif.type != NL80211_IFTYPE_ADHOC)
 598		return -EINVAL;
 599
 600	if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
 601		ht_dbg(sdata,
 602		       "BA sessions blocked - Denying BA session request %pM tid %d\n",
 603		       sta->sta.addr, tid);
 604		return -EINVAL;
 605	}
 606
 
 
 
 
 
 
 
 
 607	/*
 608	 * 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a
 609	 * member of an IBSS, and has no other existing Block Ack agreement
 610	 * with the recipient STA, then the initiating STA shall transmit a
 611	 * Probe Request frame to the recipient STA and shall not transmit an
 612	 * ADDBA Request frame unless it receives a Probe Response frame
 613	 * from the recipient within dot11ADDBAFailureTimeout.
 614	 *
 615	 * The probe request mechanism for ADDBA is currently not implemented,
 616	 * but we only build up Block Ack session with HT STAs. This information
 617	 * is set when we receive a bss info from a probe response or a beacon.
 618	 */
 619	if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 620	    !sta->sta.ht_cap.ht_supported) {
 621		ht_dbg(sdata,
 622		       "BA request denied - IBSS STA %pM does not advertise HT support\n",
 623		       pubsta->addr);
 624		return -EINVAL;
 625	}
 626
 627	spin_lock_bh(&sta->lock);
 628
 629	/* we have tried too many times, receiver does not want A-MPDU */
 630	if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
 631		ret = -EBUSY;
 632		goto err_unlock_sta;
 633	}
 634
 635	/*
 636	 * if we have tried more than HT_AGG_BURST_RETRIES times we
 637	 * will spread our requests in time to avoid stalling connection
 638	 * for too long
 639	 */
 640	if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES &&
 641	    time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] +
 642			HT_AGG_RETRIES_PERIOD)) {
 643		ht_dbg(sdata,
 644		       "BA request denied - waiting a grace period after %d failed requests on %pM tid %u\n",
 645		       sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid);
 646		ret = -EBUSY;
 647		goto err_unlock_sta;
 648	}
 649
 650	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 651	/* check if the TID is not in aggregation flow already */
 652	if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) {
 653		ht_dbg(sdata,
 654		       "BA request denied - session is not idle on %pM tid %u\n",
 655		       sta->sta.addr, tid);
 656		ret = -EAGAIN;
 657		goto err_unlock_sta;
 658	}
 659
 660	/* prepare A-MPDU MLME for Tx aggregation */
 661	tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
 662	if (!tid_tx) {
 663		ret = -ENOMEM;
 664		goto err_unlock_sta;
 665	}
 666
 667	skb_queue_head_init(&tid_tx->pending);
 668	__set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
 669
 670	tid_tx->timeout = timeout;
 
 
 671
 672	/* response timer */
 673	tid_tx->addba_resp_timer.function = sta_addba_resp_timer_expired;
 674	tid_tx->addba_resp_timer.data = (unsigned long)&sta->timer_to_tid[tid];
 675	init_timer(&tid_tx->addba_resp_timer);
 676
 677	/* tx timer */
 678	tid_tx->session_timer.function = sta_tx_agg_session_timer_expired;
 679	tid_tx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid];
 680	init_timer_deferrable(&tid_tx->session_timer);
 681
 682	/* assign a dialog token */
 683	sta->ampdu_mlme.dialog_token_allocator++;
 684	tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
 685
 686	/*
 687	 * Finally, assign it to the start array; the work item will
 688	 * collect it and move it to the normal array.
 689	 */
 690	sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
 691
 692	ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
 693
 694	/* this flow continues off the work */
 695 err_unlock_sta:
 696	spin_unlock_bh(&sta->lock);
 697	return ret;
 698}
 699EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
 700
 701static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
 702					 struct sta_info *sta, u16 tid)
 703{
 704	struct tid_ampdu_tx *tid_tx;
 705	struct ieee80211_ampdu_params params = {
 706		.sta = &sta->sta,
 707		.action = IEEE80211_AMPDU_TX_OPERATIONAL,
 708		.tid = tid,
 709		.timeout = 0,
 710		.ssn = 0,
 711	};
 712
 713	lockdep_assert_held(&sta->ampdu_mlme.mtx);
 714
 715	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 716	params.buf_size = tid_tx->buf_size;
 717	params.amsdu = tid_tx->amsdu;
 718
 719	ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n",
 720	       sta->sta.addr, tid);
 721
 722	drv_ampdu_action(local, sta->sdata, &params);
 723
 724	/*
 725	 * synchronize with TX path, while splicing the TX path
 726	 * should block so it won't put more packets onto pending.
 727	 */
 728	spin_lock_bh(&sta->lock);
 729
 730	ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
 731	/*
 732	 * Now mark as operational. This will be visible
 733	 * in the TX path, and lets it go lock-free in
 734	 * the common case.
 735	 */
 736	set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
 737	ieee80211_agg_splice_finish(sta->sdata, tid);
 738
 739	spin_unlock_bh(&sta->lock);
 740
 741	ieee80211_agg_start_txq(sta, tid, true);
 742}
 743
 744void ieee80211_start_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u16 tid)
 
 745{
 746	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 747	struct ieee80211_local *local = sdata->local;
 748	struct sta_info *sta;
 749	struct tid_ampdu_tx *tid_tx;
 750
 751	trace_api_start_tx_ba_cb(sdata, ra, tid);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 752
 753	if (tid >= IEEE80211_NUM_TIDS) {
 754		ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n",
 755		       tid, IEEE80211_NUM_TIDS);
 756		return;
 757	}
 758
 759	mutex_lock(&local->sta_mtx);
 760	sta = sta_info_get_bss(sdata, ra);
 761	if (!sta) {
 762		mutex_unlock(&local->sta_mtx);
 763		ht_dbg(sdata, "Could not find station: %pM\n", ra);
 764		return;
 765	}
 766
 767	mutex_lock(&sta->ampdu_mlme.mtx);
 768	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 769
 770	if (WARN_ON(!tid_tx)) {
 771		ht_dbg(sdata, "addBA was not requested!\n");
 772		goto unlock;
 773	}
 774
 775	if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
 776		goto unlock;
 777
 778	if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
 779		ieee80211_agg_tx_operational(local, sta, tid);
 780
 781 unlock:
 782	mutex_unlock(&sta->ampdu_mlme.mtx);
 783	mutex_unlock(&local->sta_mtx);
 784}
 785
 786void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
 787				      const u8 *ra, u16 tid)
 788{
 789	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 790	struct ieee80211_local *local = sdata->local;
 791	struct ieee80211_ra_tid *ra_tid;
 792	struct sk_buff *skb = dev_alloc_skb(0);
 793
 794	if (unlikely(!skb))
 795		return;
 796
 797	ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
 798	memcpy(&ra_tid->ra, ra, ETH_ALEN);
 799	ra_tid->tid = tid;
 
 800
 801	skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_START;
 802	skb_queue_tail(&sdata->skb_queue, skb);
 803	ieee80211_queue_work(&local->hw, &sdata->work);
 
 804}
 805EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
 806
 807int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 808				   enum ieee80211_agg_stop_reason reason)
 809{
 810	int ret;
 811
 812	mutex_lock(&sta->ampdu_mlme.mtx);
 813
 814	ret = ___ieee80211_stop_tx_ba_session(sta, tid, reason);
 815
 816	mutex_unlock(&sta->ampdu_mlme.mtx);
 817
 818	return ret;
 819}
 820
 821int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
 822{
 823	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 824	struct ieee80211_sub_if_data *sdata = sta->sdata;
 825	struct ieee80211_local *local = sdata->local;
 826	struct tid_ampdu_tx *tid_tx;
 827	int ret = 0;
 828
 829	trace_api_stop_tx_ba_session(pubsta, tid);
 830
 831	if (!local->ops->ampdu_action)
 832		return -EINVAL;
 833
 834	if (tid >= IEEE80211_NUM_TIDS)
 835		return -EINVAL;
 836
 837	spin_lock_bh(&sta->lock);
 838	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 839
 840	if (!tid_tx) {
 841		ret = -ENOENT;
 842		goto unlock;
 843	}
 844
 845	WARN(sta->reserved_tid == tid,
 846	     "Requested to stop BA session on reserved tid=%d", tid);
 847
 848	if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
 849		/* already in progress stopping it */
 850		ret = 0;
 851		goto unlock;
 852	}
 853
 854	set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
 855	ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work);
 856
 857 unlock:
 858	spin_unlock_bh(&sta->lock);
 859	return ret;
 860}
 861EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
 862
 863void ieee80211_stop_tx_ba_cb(struct ieee80211_vif *vif, u8 *ra, u8 tid)
 
 864{
 865	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 866	struct ieee80211_local *local = sdata->local;
 867	struct sta_info *sta;
 868	struct tid_ampdu_tx *tid_tx;
 869	bool send_delba = false;
 
 870
 871	trace_api_stop_tx_ba_cb(sdata, ra, tid);
 872
 873	if (tid >= IEEE80211_NUM_TIDS) {
 874		ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n",
 875		       tid, IEEE80211_NUM_TIDS);
 876		return;
 877	}
 878
 879	ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n", ra, tid);
 880
 881	mutex_lock(&local->sta_mtx);
 882
 883	sta = sta_info_get_bss(sdata, ra);
 884	if (!sta) {
 885		ht_dbg(sdata, "Could not find station: %pM\n", ra);
 886		goto unlock;
 887	}
 888
 889	mutex_lock(&sta->ampdu_mlme.mtx);
 890	spin_lock_bh(&sta->lock);
 891	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 892
 893	if (!tid_tx || !test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
 894		ht_dbg(sdata,
 895		       "unexpected callback to A-MPDU stop for %pM tid %d\n",
 896		       sta->sta.addr, tid);
 897		goto unlock_sta;
 898	}
 899
 900	if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
 901		send_delba = true;
 902
 903	ieee80211_remove_tid_tx(sta, tid);
 
 904
 905 unlock_sta:
 906	spin_unlock_bh(&sta->lock);
 907
 
 
 
 908	if (send_delba)
 909		ieee80211_send_delba(sdata, ra, tid,
 910			WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
 911
 912	mutex_unlock(&sta->ampdu_mlme.mtx);
 913 unlock:
 914	mutex_unlock(&local->sta_mtx);
 915}
 916
 917void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
 918				     const u8 *ra, u16 tid)
 919{
 920	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 921	struct ieee80211_local *local = sdata->local;
 922	struct ieee80211_ra_tid *ra_tid;
 923	struct sk_buff *skb = dev_alloc_skb(0);
 924
 925	if (unlikely(!skb))
 926		return;
 927
 928	ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
 929	memcpy(&ra_tid->ra, ra, ETH_ALEN);
 930	ra_tid->tid = tid;
 
 931
 932	skb->pkt_type = IEEE80211_SDATA_QUEUE_AGG_STOP;
 933	skb_queue_tail(&sdata->skb_queue, skb);
 934	ieee80211_queue_work(&local->hw, &sdata->work);
 
 935}
 936EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
 937
 938
 939void ieee80211_process_addba_resp(struct ieee80211_local *local,
 940				  struct sta_info *sta,
 941				  struct ieee80211_mgmt *mgmt,
 942				  size_t len)
 943{
 944	struct tid_ampdu_tx *tid_tx;
 945	struct ieee80211_txq *txq;
 946	u16 capab, tid;
 947	u8 buf_size;
 948	bool amsdu;
 949
 
 
 950	capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
 951	amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK;
 952	tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
 953	buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
 
 
 
 
 
 
 
 954	buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes);
 955
 956	txq = sta->sta.txq[tid];
 957	if (!amsdu && txq)
 958		set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags);
 959
 960	mutex_lock(&sta->ampdu_mlme.mtx);
 961
 962	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 963	if (!tid_tx)
 964		goto out;
 965
 966	if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
 967		ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n",
 968		       sta->sta.addr, tid);
 969		goto out;
 970	}
 971
 972	del_timer_sync(&tid_tx->addba_resp_timer);
 973
 974	ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n",
 975	       sta->sta.addr, tid);
 976
 977	/*
 978	 * addba_resp_timer may have fired before we got here, and
 979	 * caused WANT_STOP to be set. If the stop then was already
 980	 * processed further, STOPPING might be set.
 981	 */
 982	if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) ||
 983	    test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
 984		ht_dbg(sta->sdata,
 985		       "got addBA resp for %pM tid %d but we already gave up\n",
 986		       sta->sta.addr, tid);
 987		goto out;
 988	}
 989
 990	/*
 991	 * IEEE 802.11-2007 7.3.1.14:
 992	 * In an ADDBA Response frame, when the Status Code field
 993	 * is set to 0, the Buffer Size subfield is set to a value
 994	 * of at least 1.
 995	 */
 996	if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
 997			== WLAN_STATUS_SUCCESS && buf_size) {
 998		if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
 999				     &tid_tx->state)) {
1000			/* ignore duplicate response */
1001			goto out;
1002		}
1003
1004		tid_tx->buf_size = buf_size;
1005		tid_tx->amsdu = amsdu;
1006
1007		if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
1008			ieee80211_agg_tx_operational(local, sta, tid);
1009
1010		sta->ampdu_mlme.addba_req_num[tid] = 0;
1011
 
 
 
1012		if (tid_tx->timeout) {
1013			mod_timer(&tid_tx->session_timer,
1014				  TU_TO_EXP_TIME(tid_tx->timeout));
1015			tid_tx->last_tx = jiffies;
1016		}
1017
1018	} else {
1019		___ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED);
1020	}
1021
1022 out:
1023	mutex_unlock(&sta->ampdu_mlme.mtx);
1024}
v6.13.7
   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 - 2023 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
  61static void ieee80211_send_addba_request(struct sta_info *sta, u16 tid,
 
  62					 u8 dialog_token, u16 start_seq_num,
  63					 u16 agg_size, u16 timeout)
  64{
  65	struct ieee80211_sub_if_data *sdata = sta->sdata;
  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) +
  72			    2 + sizeof(struct ieee80211_addba_ext_ie) +
  73			    local->hw.extra_tx_headroom);
  74	if (!skb)
  75		return;
  76
  77	skb_reserve(skb, local->hw.extra_tx_headroom);
  78	mgmt = ieee80211_mgmt_ba(skb, sta->sta.addr, sdata);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  79
  80	skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
  81
  82	mgmt->u.action.category = WLAN_CATEGORY_BACK;
  83	mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
  84
  85	mgmt->u.action.u.addba_req.dialog_token = dialog_token;
  86	capab = IEEE80211_ADDBA_PARAM_AMSDU_MASK;
  87	capab |= IEEE80211_ADDBA_PARAM_POLICY_MASK;
  88	capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
  89	capab |= u16_encode_bits(agg_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
  90
  91	mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
  92
  93	mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
  94	mgmt->u.action.u.addba_req.start_seq_num =
  95					cpu_to_le16(start_seq_num << 4);
  96
  97	if (sta->sta.deflink.he_cap.has_he)
  98		ieee80211_add_addbaext(skb, 0, agg_size);
  99
 100	ieee80211_tx_skb_tid(sdata, skb, tid, -1);
 101}
 102
 103void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn)
 104{
 105	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 106	struct ieee80211_local *local = sdata->local;
 107	struct sk_buff *skb;
 108	struct ieee80211_bar *bar;
 109	u16 bar_control = 0;
 110
 111	skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
 112	if (!skb)
 113		return;
 114
 115	skb_reserve(skb, local->hw.extra_tx_headroom);
 116	bar = skb_put_zero(skb, sizeof(*bar));
 
 117	bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
 118					 IEEE80211_STYPE_BACK_REQ);
 119	memcpy(bar->ra, ra, ETH_ALEN);
 120	memcpy(bar->ta, sdata->vif.addr, ETH_ALEN);
 121	bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
 122	bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
 123	bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT);
 124	bar->control = cpu_to_le16(bar_control);
 125	bar->start_seq_num = cpu_to_le16(ssn);
 126
 127	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
 128					IEEE80211_TX_CTL_REQ_TX_STATUS;
 129	ieee80211_tx_skb_tid(sdata, skb, tid, -1);
 130}
 131EXPORT_SYMBOL(ieee80211_send_bar);
 132
 133void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
 134			     struct tid_ampdu_tx *tid_tx)
 135{
 136	lockdep_assert_wiphy(sta->local->hw.wiphy);
 137	lockdep_assert_held(&sta->lock);
 138	rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
 139}
 140
 141/*
 142 * When multiple aggregation sessions on multiple stations
 143 * are being created/destroyed simultaneously, we need to
 144 * refcount the global queue stop caused by that in order
 145 * to not get into a situation where one of the aggregation
 146 * setup or teardown re-enables queues before the other is
 147 * ready to handle that.
 148 *
 149 * These two functions take care of this issue by keeping
 150 * a global "agg_queue_stop" refcount.
 151 */
 152static void __acquires(agg_queue)
 153ieee80211_stop_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
 154{
 155	int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
 156
 157	/* we do refcounting here, so don't use the queue reason refcounting */
 158
 159	if (atomic_inc_return(&sdata->local->agg_queue_stop[queue]) == 1)
 160		ieee80211_stop_queue_by_reason(
 161			&sdata->local->hw, queue,
 162			IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
 163			false);
 164	__acquire(agg_queue);
 165}
 166
 167static void __releases(agg_queue)
 168ieee80211_wake_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
 169{
 170	int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
 171
 172	if (atomic_dec_return(&sdata->local->agg_queue_stop[queue]) == 0)
 173		ieee80211_wake_queue_by_reason(
 174			&sdata->local->hw, queue,
 175			IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
 176			false);
 177	__release(agg_queue);
 178}
 179
 180static void
 181ieee80211_agg_stop_txq(struct sta_info *sta, int tid)
 182{
 183	struct ieee80211_txq *txq = sta->sta.txq[tid];
 184	struct ieee80211_sub_if_data *sdata;
 185	struct fq *fq;
 186	struct txq_info *txqi;
 187
 188	if (!txq)
 189		return;
 190
 191	txqi = to_txq_info(txq);
 192	sdata = vif_to_sdata(txq->vif);
 193	fq = &sdata->local->fq;
 194
 195	/* Lock here to protect against further seqno updates on dequeue */
 196	spin_lock_bh(&fq->lock);
 197	set_bit(IEEE80211_TXQ_STOP, &txqi->flags);
 198	spin_unlock_bh(&fq->lock);
 199}
 200
 201static void
 202ieee80211_agg_start_txq(struct sta_info *sta, int tid, bool enable)
 203{
 204	struct ieee80211_txq *txq = sta->sta.txq[tid];
 205	struct txq_info *txqi;
 206
 207	lockdep_assert_wiphy(sta->local->hw.wiphy);
 208
 209	if (!txq)
 210		return;
 211
 212	txqi = to_txq_info(txq);
 213
 214	if (enable)
 215		set_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
 216	else
 217		clear_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
 218
 219	clear_bit(IEEE80211_TXQ_STOP, &txqi->flags);
 220	local_bh_disable();
 221	rcu_read_lock();
 222	schedule_and_wake_txq(sta->sdata->local, txqi);
 223	rcu_read_unlock();
 224	local_bh_enable();
 225}
 226
 227/*
 228 * splice packets from the STA's pending to the local pending,
 229 * requires a call to ieee80211_agg_splice_finish later
 230 */
 231static void __acquires(agg_queue)
 232ieee80211_agg_splice_packets(struct ieee80211_sub_if_data *sdata,
 233			     struct tid_ampdu_tx *tid_tx, u16 tid)
 234{
 235	struct ieee80211_local *local = sdata->local;
 236	int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
 237	unsigned long flags;
 238
 239	ieee80211_stop_queue_agg(sdata, tid);
 240
 241	if (WARN(!tid_tx,
 242		 "TID %d gone but expected when splicing aggregates from the pending queue\n",
 243		 tid))
 244		return;
 245
 246	if (!skb_queue_empty(&tid_tx->pending)) {
 247		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
 248		/* copy over remaining packets */
 249		skb_queue_splice_tail_init(&tid_tx->pending,
 250					   &local->pending[queue]);
 251		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
 252	}
 253}
 254
 255static void __releases(agg_queue)
 256ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid)
 257{
 258	ieee80211_wake_queue_agg(sdata, tid);
 259}
 260
 261static void ieee80211_remove_tid_tx(struct sta_info *sta, int tid)
 262{
 263	struct tid_ampdu_tx *tid_tx;
 264
 265	lockdep_assert_wiphy(sta->local->hw.wiphy);
 266	lockdep_assert_held(&sta->lock);
 267
 268	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 269
 270	/*
 271	 * When we get here, the TX path will not be lockless any more wrt.
 272	 * aggregation, since the OPERATIONAL bit has long been cleared.
 273	 * Thus it will block on getting the lock, if it occurs. So if we
 274	 * stop the queue now, we will not get any more packets, and any
 275	 * that might be being processed will wait for us here, thereby
 276	 * guaranteeing that no packets go to the tid_tx pending queue any
 277	 * more.
 278	 */
 279
 280	ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
 281
 282	/* future packets must not find the tid_tx struct any more */
 283	ieee80211_assign_tid_tx(sta, tid, NULL);
 284
 285	ieee80211_agg_splice_finish(sta->sdata, tid);
 
 286
 287	kfree_rcu(tid_tx, rcu_head);
 288}
 289
 290int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 291				   enum ieee80211_agg_stop_reason reason)
 292{
 293	struct ieee80211_local *local = sta->local;
 294	struct tid_ampdu_tx *tid_tx;
 295	struct ieee80211_ampdu_params params = {
 296		.sta = &sta->sta,
 297		.tid = tid,
 298		.buf_size = 0,
 299		.amsdu = false,
 300		.timeout = 0,
 301		.ssn = 0,
 302	};
 303	int ret;
 304
 305	lockdep_assert_wiphy(sta->local->hw.wiphy);
 306
 307	switch (reason) {
 308	case AGG_STOP_DECLINED:
 309	case AGG_STOP_LOCAL_REQUEST:
 310	case AGG_STOP_PEER_REQUEST:
 311		params.action = IEEE80211_AMPDU_TX_STOP_CONT;
 312		break;
 313	case AGG_STOP_DESTROY_STA:
 314		params.action = IEEE80211_AMPDU_TX_STOP_FLUSH;
 315		break;
 316	default:
 317		WARN_ON_ONCE(1);
 318		return -EINVAL;
 319	}
 320
 321	spin_lock_bh(&sta->lock);
 322
 323	/* free struct pending for start, if present */
 324	tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
 325	kfree(tid_tx);
 326	sta->ampdu_mlme.tid_start_tx[tid] = NULL;
 327
 328	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 329	if (!tid_tx) {
 330		spin_unlock_bh(&sta->lock);
 331		return -ENOENT;
 332	}
 333
 334	/*
 335	 * if we're already stopping ignore any new requests to stop
 336	 * unless we're destroying it in which case notify the driver
 337	 */
 338	if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
 339		spin_unlock_bh(&sta->lock);
 340		if (reason != AGG_STOP_DESTROY_STA)
 341			return -EALREADY;
 342		params.action = IEEE80211_AMPDU_TX_STOP_FLUSH_CONT;
 343		ret = drv_ampdu_action(local, sta->sdata, &params);
 344		WARN_ON_ONCE(ret);
 345		return 0;
 346	}
 347
 348	if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
 349		/* not even started yet! */
 350		ieee80211_assign_tid_tx(sta, tid, NULL);
 351		spin_unlock_bh(&sta->lock);
 352		kfree_rcu(tid_tx, rcu_head);
 353		return 0;
 354	}
 355
 356	set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
 357
 358	ieee80211_agg_stop_txq(sta, tid);
 359
 360	spin_unlock_bh(&sta->lock);
 361
 362	ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n",
 363	       sta->sta.addr, tid);
 364
 365	del_timer_sync(&tid_tx->addba_resp_timer);
 366	del_timer_sync(&tid_tx->session_timer);
 367
 368	/*
 369	 * After this packets are no longer handed right through
 370	 * to the driver but are put onto tid_tx->pending instead,
 371	 * with locking to ensure proper access.
 372	 */
 373	clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
 374
 375	/*
 376	 * There might be a few packets being processed right now (on
 377	 * another CPU) that have already gotten past the aggregation
 378	 * check when it was still OPERATIONAL and consequently have
 379	 * IEEE80211_TX_CTL_AMPDU set. In that case, this code might
 380	 * call into the driver at the same time or even before the
 381	 * TX paths calls into it, which could confuse the driver.
 382	 *
 383	 * Wait for all currently running TX paths to finish before
 384	 * telling the driver. New packets will not go through since
 385	 * the aggregation session is no longer OPERATIONAL.
 386	 */
 387	if (!local->in_reconfig)
 388		synchronize_net();
 389
 390	tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ?
 391					WLAN_BACK_RECIPIENT :
 392					WLAN_BACK_INITIATOR;
 393	tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST;
 394
 395	ret = drv_ampdu_action(local, sta->sdata, &params);
 396
 397	/* HW shall not deny going back to legacy */
 398	if (WARN_ON(ret)) {
 399		/*
 400		 * We may have pending packets get stuck in this case...
 401		 * Not bothering with a workaround for now.
 402		 */
 403	}
 404
 405	/*
 406	 * In the case of AGG_STOP_DESTROY_STA, the driver won't
 407	 * necessarily call ieee80211_stop_tx_ba_cb(), so this may
 408	 * seem like we can leave the tid_tx data pending forever.
 409	 * This is true, in a way, but "forever" is only until the
 410	 * station struct is actually destroyed. In the meantime,
 411	 * leaving it around ensures that we don't transmit packets
 412	 * to the driver on this TID which might confuse it.
 413	 */
 414
 415	return 0;
 416}
 417
 418/*
 419 * After sending add Block Ack request we activated a timer until
 420 * add Block Ack response will arrive from the recipient.
 421 * If this timer expires sta_addba_resp_timer_expired will be executed.
 422 */
 423static void sta_addba_resp_timer_expired(struct timer_list *t)
 424{
 425	struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, addba_resp_timer);
 426	struct sta_info *sta = tid_tx->sta;
 427	u8 tid = tid_tx->tid;
 
 
 
 
 
 428
 429	/* check if the TID waits for addBA response */
 430	if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
 
 
 
 
 431		ht_dbg(sta->sdata,
 432		       "timer expired on %pM tid %d not expecting addBA response\n",
 433		       sta->sta.addr, tid);
 434		return;
 435	}
 436
 437	ht_dbg(sta->sdata, "addBA response timer expired on %pM tid %d\n",
 438	       sta->sta.addr, tid);
 439
 440	ieee80211_stop_tx_ba_session(&sta->sta, tid);
 441}
 442
 443static void ieee80211_send_addba_with_timeout(struct sta_info *sta,
 444					      struct tid_ampdu_tx *tid_tx)
 445{
 446	struct ieee80211_sub_if_data *sdata = sta->sdata;
 447	struct ieee80211_local *local = sta->local;
 448	u8 tid = tid_tx->tid;
 449	u16 buf_size;
 450
 451	if (WARN_ON_ONCE(test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state) ||
 452			 test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state)))
 453		return;
 454
 455	lockdep_assert_wiphy(sta->local->hw.wiphy);
 456
 457	/* activate the timer for the recipient's addBA response */
 458	mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
 459	ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n",
 460	       sta->sta.addr, tid);
 461
 462	spin_lock_bh(&sta->lock);
 463	sta->ampdu_mlme.last_addba_req_time[tid] = jiffies;
 464	sta->ampdu_mlme.addba_req_num[tid]++;
 465	spin_unlock_bh(&sta->lock);
 466
 467	if (sta->sta.deflink.eht_cap.has_eht) {
 468		buf_size = local->hw.max_tx_aggregation_subframes;
 469	} else if (sta->sta.deflink.he_cap.has_he) {
 470		buf_size = min_t(u16, local->hw.max_tx_aggregation_subframes,
 471				 IEEE80211_MAX_AMPDU_BUF_HE);
 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(sta, tid, tid_tx->dialog_token,
 484				     tid_tx->ssn, buf_size, tid_tx->timeout);
 485
 486	WARN_ON(test_and_set_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state));
 487}
 488
 489void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
 490{
 491	struct tid_ampdu_tx *tid_tx;
 492	struct ieee80211_local *local = sta->local;
 493	struct ieee80211_sub_if_data *sdata = sta->sdata;
 494	struct ieee80211_ampdu_params params = {
 495		.sta = &sta->sta,
 496		.action = IEEE80211_AMPDU_TX_START,
 497		.tid = tid,
 498		.buf_size = 0,
 499		.amsdu = false,
 500		.timeout = 0,
 501	};
 502	int ret;
 503
 504	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 505
 506	/*
 507	 * Start queuing up packets for this aggregation session.
 508	 * We're going to release them once the driver is OK with
 509	 * that.
 510	 */
 511	clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
 512
 
 
 513	/*
 514	 * Make sure no packets are being processed. This ensures that
 515	 * we have a valid starting sequence number and that in-flight
 516	 * packets have been flushed out and no packets for this TID
 517	 * will go into the driver during the ampdu_action call.
 518	 */
 519	synchronize_net();
 520
 521	params.ssn = sta->tid_seq[tid] >> 4;
 522	ret = drv_ampdu_action(local, sdata, &params);
 523	tid_tx->ssn = params.ssn;
 524	if (ret == IEEE80211_AMPDU_TX_START_DELAY_ADDBA) {
 525		return;
 526	} else if (ret == IEEE80211_AMPDU_TX_START_IMMEDIATE) {
 527		/*
 528		 * We didn't send the request yet, so don't need to check
 529		 * here if we already got a response, just mark as driver
 530		 * ready immediately.
 531		 */
 532		set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state);
 533	} else if (ret) {
 534		ht_dbg(sdata,
 535		       "BA request denied - HW unavailable for %pM tid %d\n",
 536		       sta->sta.addr, tid);
 537		spin_lock_bh(&sta->lock);
 538		ieee80211_agg_splice_packets(sdata, tid_tx, tid);
 539		ieee80211_assign_tid_tx(sta, tid, NULL);
 540		ieee80211_agg_splice_finish(sdata, tid);
 541		spin_unlock_bh(&sta->lock);
 542
 543		ieee80211_agg_start_txq(sta, tid, false);
 544
 545		kfree_rcu(tid_tx, rcu_head);
 546		return;
 547	}
 548
 549	ieee80211_send_addba_with_timeout(sta, tid_tx);
 550}
 
 
 551
 552void ieee80211_refresh_tx_agg_session_timer(struct ieee80211_sta *pubsta,
 553					    u16 tid)
 554{
 555	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 556	struct tid_ampdu_tx *tid_tx;
 557
 558	if (WARN_ON_ONCE(tid >= IEEE80211_NUM_TIDS))
 559		return;
 560
 561	tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 562	if (!tid_tx)
 563		return;
 564
 565	tid_tx->last_tx = jiffies;
 566}
 567EXPORT_SYMBOL(ieee80211_refresh_tx_agg_session_timer);
 568
 569/*
 570 * After accepting the AddBA Response we activated a timer,
 571 * resetting it after each frame that we send.
 572 */
 573static void sta_tx_agg_session_timer_expired(struct timer_list *t)
 574{
 575	struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, session_timer);
 576	struct sta_info *sta = tid_tx->sta;
 577	u8 tid = tid_tx->tid;
 
 
 
 
 
 
 578	unsigned long timeout;
 579
 580	if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
 
 
 
 581		return;
 582	}
 583
 584	timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout);
 585	if (time_is_after_jiffies(timeout)) {
 586		mod_timer(&tid_tx->session_timer, timeout);
 
 587		return;
 588	}
 589
 
 
 590	ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n",
 591	       sta->sta.addr, tid);
 592
 593	ieee80211_stop_tx_ba_session(&sta->sta, tid);
 594}
 595
 596int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
 597				  u16 timeout)
 598{
 599	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 600	struct ieee80211_sub_if_data *sdata = sta->sdata;
 601	struct ieee80211_local *local = sdata->local;
 602	struct tid_ampdu_tx *tid_tx;
 603	int ret = 0;
 604
 605	trace_api_start_tx_ba_session(pubsta, tid);
 606
 607	if (WARN(sta->reserved_tid == tid,
 608		 "Requested to start BA session on reserved tid=%d", tid))
 609		return -EINVAL;
 610
 611	if (!pubsta->deflink.ht_cap.ht_supported &&
 612	    !pubsta->deflink.vht_cap.vht_supported &&
 613	    !pubsta->deflink.he_cap.has_he &&
 614	    !pubsta->deflink.eht_cap.has_eht)
 615		return -EINVAL;
 616
 617	if (WARN_ON_ONCE(!local->ops->ampdu_action))
 618		return -EINVAL;
 619
 620	if ((tid >= IEEE80211_NUM_TIDS) ||
 621	    !ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) ||
 622	    ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW))
 623		return -EINVAL;
 624
 625	if (WARN_ON(tid >= IEEE80211_FIRST_TSPEC_TSID))
 626		return -EINVAL;
 627
 628	ht_dbg(sdata, "Open BA session requested for %pM tid %u\n",
 629	       pubsta->addr, tid);
 630
 631	if (sdata->vif.type != NL80211_IFTYPE_STATION &&
 632	    sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
 633	    sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
 634	    sdata->vif.type != NL80211_IFTYPE_AP &&
 635	    sdata->vif.type != NL80211_IFTYPE_ADHOC)
 636		return -EINVAL;
 637
 638	if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
 639		ht_dbg(sdata,
 640		       "BA sessions blocked - Denying BA session request %pM tid %d\n",
 641		       sta->sta.addr, tid);
 642		return -EINVAL;
 643	}
 644
 645	if (test_sta_flag(sta, WLAN_STA_MFP) &&
 646	    !test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
 647		ht_dbg(sdata,
 648		       "MFP STA not authorized - deny BA session request %pM tid %d\n",
 649		       sta->sta.addr, tid);
 650		return -EINVAL;
 651	}
 652
 653	/*
 654	 * 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a
 655	 * member of an IBSS, and has no other existing Block Ack agreement
 656	 * with the recipient STA, then the initiating STA shall transmit a
 657	 * Probe Request frame to the recipient STA and shall not transmit an
 658	 * ADDBA Request frame unless it receives a Probe Response frame
 659	 * from the recipient within dot11ADDBAFailureTimeout.
 660	 *
 661	 * The probe request mechanism for ADDBA is currently not implemented,
 662	 * but we only build up Block Ack session with HT STAs. This information
 663	 * is set when we receive a bss info from a probe response or a beacon.
 664	 */
 665	if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC &&
 666	    !sta->sta.deflink.ht_cap.ht_supported) {
 667		ht_dbg(sdata,
 668		       "BA request denied - IBSS STA %pM does not advertise HT support\n",
 669		       pubsta->addr);
 670		return -EINVAL;
 671	}
 672
 673	spin_lock_bh(&sta->lock);
 674
 675	/* we have tried too many times, receiver does not want A-MPDU */
 676	if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
 677		ret = -EBUSY;
 678		goto err_unlock_sta;
 679	}
 680
 681	/*
 682	 * if we have tried more than HT_AGG_BURST_RETRIES times we
 683	 * will spread our requests in time to avoid stalling connection
 684	 * for too long
 685	 */
 686	if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES &&
 687	    time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] +
 688			HT_AGG_RETRIES_PERIOD)) {
 689		ht_dbg(sdata,
 690		       "BA request denied - %d failed requests on %pM tid %u\n",
 691		       sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid);
 692		ret = -EBUSY;
 693		goto err_unlock_sta;
 694	}
 695
 696	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 697	/* check if the TID is not in aggregation flow already */
 698	if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) {
 699		ht_dbg(sdata,
 700		       "BA request denied - session is not idle on %pM tid %u\n",
 701		       sta->sta.addr, tid);
 702		ret = -EAGAIN;
 703		goto err_unlock_sta;
 704	}
 705
 706	/* prepare A-MPDU MLME for Tx aggregation */
 707	tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
 708	if (!tid_tx) {
 709		ret = -ENOMEM;
 710		goto err_unlock_sta;
 711	}
 712
 713	skb_queue_head_init(&tid_tx->pending);
 714	__set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
 715
 716	tid_tx->timeout = timeout;
 717	tid_tx->sta = sta;
 718	tid_tx->tid = tid;
 719
 720	/* response timer */
 721	timer_setup(&tid_tx->addba_resp_timer, sta_addba_resp_timer_expired, 0);
 
 
 722
 723	/* tx timer */
 724	timer_setup(&tid_tx->session_timer,
 725		    sta_tx_agg_session_timer_expired, TIMER_DEFERRABLE);
 
 726
 727	/* assign a dialog token */
 728	sta->ampdu_mlme.dialog_token_allocator++;
 729	tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
 730
 731	/*
 732	 * Finally, assign it to the start array; the work item will
 733	 * collect it and move it to the normal array.
 734	 */
 735	sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
 736
 737	wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
 738
 739	/* this flow continues off the work */
 740 err_unlock_sta:
 741	spin_unlock_bh(&sta->lock);
 742	return ret;
 743}
 744EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
 745
 746static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
 747					 struct sta_info *sta, u16 tid)
 748{
 749	struct tid_ampdu_tx *tid_tx;
 750	struct ieee80211_ampdu_params params = {
 751		.sta = &sta->sta,
 752		.action = IEEE80211_AMPDU_TX_OPERATIONAL,
 753		.tid = tid,
 754		.timeout = 0,
 755		.ssn = 0,
 756	};
 757
 758	lockdep_assert_wiphy(sta->local->hw.wiphy);
 759
 760	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 761	params.buf_size = tid_tx->buf_size;
 762	params.amsdu = tid_tx->amsdu;
 763
 764	ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n",
 765	       sta->sta.addr, tid);
 766
 767	drv_ampdu_action(local, sta->sdata, &params);
 768
 769	/*
 770	 * synchronize with TX path, while splicing the TX path
 771	 * should block so it won't put more packets onto pending.
 772	 */
 773	spin_lock_bh(&sta->lock);
 774
 775	ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
 776	/*
 777	 * Now mark as operational. This will be visible
 778	 * in the TX path, and lets it go lock-free in
 779	 * the common case.
 780	 */
 781	set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
 782	ieee80211_agg_splice_finish(sta->sdata, tid);
 783
 784	spin_unlock_bh(&sta->lock);
 785
 786	ieee80211_agg_start_txq(sta, tid, true);
 787}
 788
 789void ieee80211_start_tx_ba_cb(struct sta_info *sta, int tid,
 790			      struct tid_ampdu_tx *tid_tx)
 791{
 792	struct ieee80211_sub_if_data *sdata = sta->sdata;
 793	struct ieee80211_local *local = sdata->local;
 
 
 794
 795	lockdep_assert_wiphy(sta->local->hw.wiphy);
 796
 797	if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
 798		return;
 799
 800	if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state) ||
 801	    test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state))
 802		return;
 803
 804	if (!test_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state)) {
 805		ieee80211_send_addba_with_timeout(sta, tid_tx);
 806		/* RESPONSE_RECEIVED state would trigger the flow again */
 807		return;
 808	}
 809
 810	if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
 811		ieee80211_agg_tx_operational(local, sta, tid);
 812}
 813
 814static struct tid_ampdu_tx *
 815ieee80211_lookup_tid_tx(struct ieee80211_sub_if_data *sdata,
 816			const u8 *ra, u16 tid, struct sta_info **sta)
 817{
 818	struct tid_ampdu_tx *tid_tx;
 819
 820	if (tid >= IEEE80211_NUM_TIDS) {
 821		ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n",
 822		       tid, IEEE80211_NUM_TIDS);
 823		return NULL;
 824	}
 825
 826	*sta = sta_info_get_bss(sdata, ra);
 827	if (!*sta) {
 
 
 828		ht_dbg(sdata, "Could not find station: %pM\n", ra);
 829		return NULL;
 830	}
 831
 832	tid_tx = rcu_dereference((*sta)->ampdu_mlme.tid_tx[tid]);
 
 833
 834	if (WARN_ON(!tid_tx))
 835		ht_dbg(sdata, "addBA was not requested!\n");
 
 
 
 
 
 836
 837	return tid_tx;
 
 
 
 
 
 838}
 839
 840void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
 841				      const u8 *ra, u16 tid)
 842{
 843	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 844	struct ieee80211_local *local = sdata->local;
 845	struct sta_info *sta;
 846	struct tid_ampdu_tx *tid_tx;
 847
 848	trace_api_start_tx_ba_cb(sdata, ra, tid);
 
 849
 850	rcu_read_lock();
 851	tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
 852	if (!tid_tx)
 853		goto out;
 854
 855	set_bit(HT_AGG_STATE_START_CB, &tid_tx->state);
 856	wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
 857 out:
 858	rcu_read_unlock();
 859}
 860EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
 861
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 862int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
 863{
 864	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 865	struct ieee80211_sub_if_data *sdata = sta->sdata;
 866	struct ieee80211_local *local = sdata->local;
 867	struct tid_ampdu_tx *tid_tx;
 868	int ret = 0;
 869
 870	trace_api_stop_tx_ba_session(pubsta, tid);
 871
 872	if (!local->ops->ampdu_action)
 873		return -EINVAL;
 874
 875	if (tid >= IEEE80211_NUM_TIDS)
 876		return -EINVAL;
 877
 878	spin_lock_bh(&sta->lock);
 879	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 880
 881	if (!tid_tx) {
 882		ret = -ENOENT;
 883		goto unlock;
 884	}
 885
 886	WARN(sta->reserved_tid == tid,
 887	     "Requested to stop BA session on reserved tid=%d", tid);
 888
 889	if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
 890		/* already in progress stopping it */
 891		ret = 0;
 892		goto unlock;
 893	}
 894
 895	set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
 896	wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
 897
 898 unlock:
 899	spin_unlock_bh(&sta->lock);
 900	return ret;
 901}
 902EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
 903
 904void ieee80211_stop_tx_ba_cb(struct sta_info *sta, int tid,
 905			     struct tid_ampdu_tx *tid_tx)
 906{
 907	struct ieee80211_sub_if_data *sdata = sta->sdata;
 
 
 
 908	bool send_delba = false;
 909	bool start_txq = false;
 910
 911	ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n",
 912	       sta->sta.addr, tid);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 913
 
 914	spin_lock_bh(&sta->lock);
 
 915
 916	if (!test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
 917		ht_dbg(sdata,
 918		       "unexpected callback to A-MPDU stop for %pM tid %d\n",
 919		       sta->sta.addr, tid);
 920		goto unlock_sta;
 921	}
 922
 923	if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
 924		send_delba = true;
 925
 926	ieee80211_remove_tid_tx(sta, tid);
 927	start_txq = true;
 928
 929 unlock_sta:
 930	spin_unlock_bh(&sta->lock);
 931
 932	if (start_txq)
 933		ieee80211_agg_start_txq(sta, tid, false);
 934
 935	if (send_delba)
 936		ieee80211_send_delba(sdata, sta->sta.addr, tid,
 937			WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
 
 
 
 
 938}
 939
 940void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
 941				     const u8 *ra, u16 tid)
 942{
 943	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
 944	struct ieee80211_local *local = sdata->local;
 945	struct sta_info *sta;
 946	struct tid_ampdu_tx *tid_tx;
 947
 948	trace_api_stop_tx_ba_cb(sdata, ra, tid);
 
 949
 950	rcu_read_lock();
 951	tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
 952	if (!tid_tx)
 953		goto out;
 954
 955	set_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state);
 956	wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
 957 out:
 958	rcu_read_unlock();
 959}
 960EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
 961
 962
 963void ieee80211_process_addba_resp(struct ieee80211_local *local,
 964				  struct sta_info *sta,
 965				  struct ieee80211_mgmt *mgmt,
 966				  size_t len)
 967{
 968	struct tid_ampdu_tx *tid_tx;
 969	struct ieee80211_txq *txq;
 970	u16 capab, tid, buf_size;
 
 971	bool amsdu;
 972
 973	lockdep_assert_wiphy(sta->local->hw.wiphy);
 974
 975	capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
 976	amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK;
 977	tid = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_TID_MASK);
 978	buf_size = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
 979
 980	ieee80211_retrieve_addba_ext_data(sta,
 981					  mgmt->u.action.u.addba_resp.variable,
 982					  len - offsetof(typeof(*mgmt),
 983							 u.action.u.addba_resp.variable),
 984					  &buf_size);
 985
 986	buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes);
 987
 988	txq = sta->sta.txq[tid];
 989	if (!amsdu && txq)
 990		set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags);
 991
 
 
 992	tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
 993	if (!tid_tx)
 994		return;
 995
 996	if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
 997		ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n",
 998		       sta->sta.addr, tid);
 999		return;
1000	}
1001
1002	del_timer_sync(&tid_tx->addba_resp_timer);
1003
1004	ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n",
1005	       sta->sta.addr, tid);
1006
1007	/*
1008	 * addba_resp_timer may have fired before we got here, and
1009	 * caused WANT_STOP to be set. If the stop then was already
1010	 * processed further, STOPPING might be set.
1011	 */
1012	if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) ||
1013	    test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
1014		ht_dbg(sta->sdata,
1015		       "got addBA resp for %pM tid %d but we already gave up\n",
1016		       sta->sta.addr, tid);
1017		return;
1018	}
1019
1020	/*
1021	 * IEEE 802.11-2007 7.3.1.14:
1022	 * In an ADDBA Response frame, when the Status Code field
1023	 * is set to 0, the Buffer Size subfield is set to a value
1024	 * of at least 1.
1025	 */
1026	if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
1027			== WLAN_STATUS_SUCCESS && buf_size) {
1028		if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
1029				     &tid_tx->state)) {
1030			/* ignore duplicate response */
1031			return;
1032		}
1033
1034		tid_tx->buf_size = buf_size;
1035		tid_tx->amsdu = amsdu;
1036
1037		if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
1038			ieee80211_agg_tx_operational(local, sta, tid);
1039
1040		sta->ampdu_mlme.addba_req_num[tid] = 0;
1041
1042		tid_tx->timeout =
1043			le16_to_cpu(mgmt->u.action.u.addba_resp.timeout);
1044
1045		if (tid_tx->timeout) {
1046			mod_timer(&tid_tx->session_timer,
1047				  TU_TO_EXP_TIME(tid_tx->timeout));
1048			tid_tx->last_tx = jiffies;
1049		}
1050
1051	} else {
1052		__ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED);
1053	}
 
 
 
1054}