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Release 4.8 net/mac80211/agg-tx.c

Directory: net/mac80211
/*
 * HT handling
 *
 * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
 * Copyright 2002-2005, Instant802 Networks, Inc.
 * Copyright 2005-2006, Devicescape Software, Inc.
 * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
 * Copyright 2007-2010, Intel Corporation
 * Copyright(c) 2015 Intel Deutschland GmbH
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/ieee80211.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "wme.h"

/**
 * DOC: TX A-MPDU aggregation
 *
 * Aggregation on the TX side requires setting the hardware flag
 * %IEEE80211_HW_AMPDU_AGGREGATION. The driver will then be handed
 * packets with a flag indicating A-MPDU aggregation. The driver
 * or device is responsible for actually aggregating the frames,
 * as well as deciding how many and which to aggregate.
 *
 * When TX aggregation is started by some subsystem (usually the rate
 * control algorithm would be appropriate) by calling the
 * ieee80211_start_tx_ba_session() function, the driver will be
 * notified via its @ampdu_action function, with the
 * %IEEE80211_AMPDU_TX_START action.
 *
 * In response to that, the driver is later required to call the
 * ieee80211_start_tx_ba_cb_irqsafe() function, which will really
 * start the aggregation session after the peer has also responded.
 * If the peer responds negatively, the session will be stopped
 * again right away. Note that it is possible for the aggregation
 * session to be stopped before the driver has indicated that it
 * is done setting it up, in which case it must not indicate the
 * setup completion.
 *
 * Also note that, since we also need to wait for a response from
 * the peer, the driver is notified of the completion of the
 * handshake by the %IEEE80211_AMPDU_TX_OPERATIONAL action to the
 * @ampdu_action callback.
 *
 * Similarly, when the aggregation session is stopped by the peer
 * or something calling ieee80211_stop_tx_ba_session(), the driver's
 * @ampdu_action function will be called with the action
 * %IEEE80211_AMPDU_TX_STOP. In this case, the call must not fail,
 * and the driver must later call ieee80211_stop_tx_ba_cb_irqsafe().
 * Note that the sta can get destroyed before the BA tear down is
 * complete.
 */


static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata, const u8 *da, u16 tid, u8 dialog_token, u16 start_seq_num, u16 agg_size, u16 timeout) { struct ieee80211_local *local = sdata->local; struct sk_buff *skb; struct ieee80211_mgmt *mgmt; u16 capab; skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom); if (!skb) return; skb_reserve(skb, local->hw.extra_tx_headroom); mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24); memset(mgmt, 0, 24); memcpy(mgmt->da, da, ETH_ALEN); memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); if (sdata->vif.type == NL80211_IFTYPE_AP || sdata->vif.type == NL80211_IFTYPE_AP_VLAN || sdata->vif.type == NL80211_IFTYPE_MESH_POINT) memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); else if (sdata->vif.type == NL80211_IFTYPE_STATION) memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN); else if (sdata->vif.type == NL80211_IFTYPE_ADHOC) memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN); mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | IEEE80211_STYPE_ACTION); skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req)); mgmt->u.action.category = WLAN_CATEGORY_BACK; mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ; mgmt->u.action.u.addba_req.dialog_token = dialog_token; capab = (u16)(1 << 0); /* bit 0 A-MSDU support */ capab |= (u16)(1 << 1); /* bit 1 aggregation policy */ capab |= (u16)(tid << 2); /* bit 5:2 TID number */ capab |= (u16)(agg_size << 6); /* bit 15:6 max size of aggergation */ mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab); mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout); mgmt->u.action.u.addba_req.start_seq_num = cpu_to_le16(start_seq_num << 4); ieee80211_tx_skb(sdata, skb); }

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johannes bergjohannes berg36188.05%450.00%
alexander simonalexander simon286.83%112.50%
emmanuel grumbachemmanuel grumbach122.93%112.50%
thomas pedersenthomas pedersen81.95%112.50%
karl beldankarl beldan10.24%112.50%
Total410100.00%8100.00%


void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); struct ieee80211_local *local = sdata->local; struct sk_buff *skb; struct ieee80211_bar *bar; u16 bar_control = 0; skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom); if (!skb) return; skb_reserve(skb, local->hw.extra_tx_headroom); bar = (struct ieee80211_bar *)skb_put(skb, sizeof(*bar)); memset(bar, 0, sizeof(*bar)); bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_BACK_REQ); memcpy(bar->ra, ra, ETH_ALEN); memcpy(bar->ta, sdata->vif.addr, ETH_ALEN); bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL; bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA; bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT); bar->control = cpu_to_le16(bar_control); bar->start_seq_num = cpu_to_le16(ssn); IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT | IEEE80211_TX_CTL_REQ_TX_STATUS; ieee80211_tx_skb_tid(sdata, skb, tid); }

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johannes bergjohannes berg20191.78%342.86%
felix fietkaufelix fietkau125.48%114.29%
helmut schaahelmut schaa41.83%228.57%
christian lamparterchristian lamparter20.91%114.29%
Total219100.00%7100.00%

EXPORT_SYMBOL(ieee80211_send_bar);
void ieee80211_assign_tid_tx(struct sta_info *sta, int tid, struct tid_ampdu_tx *tid_tx) { lockdep_assert_held(&sta->ampdu_mlme.mtx); lockdep_assert_held(&sta->lock); rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx); }

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/* * When multiple aggregation sessions on multiple stations * are being created/destroyed simultaneously, we need to * refcount the global queue stop caused by that in order * to not get into a situation where one of the aggregation * setup or teardown re-enables queues before the other is * ready to handle that. * * These two functions take care of this issue by keeping * a global "agg_queue_stop" refcount. */
static void __acquires(agg_queue) ieee80211_stop_queue_agg(struct ieee80211_sub_if_data *sdata, int tid) { int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)]; /* we do refcounting here, so don't use the queue reason refcounting */ if (atomic_inc_return(&sdata->local->agg_queue_stop[queue]) == 1) ieee80211_stop_queue_by_reason( &sdata->local->hw, queue, IEEE80211_QUEUE_STOP_REASON_AGGREGATION, false); __acquire(agg_queue); }

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johannes bergjohannes berg6995.83%150.00%
luciano coelholuciano coelho34.17%150.00%
Total72100.00%2100.00%


static void __releases(agg_queue) ieee80211_wake_queue_agg(struct ieee80211_sub_if_data *sdata, int tid) { int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)]; if (atomic_dec_return(&sdata->local->agg_queue_stop[queue]) == 0) ieee80211_wake_queue_by_reason( &sdata->local->hw, queue, IEEE80211_QUEUE_STOP_REASON_AGGREGATION, false); __release(agg_queue); }

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luciano coelholuciano coelho22.82%150.00%
Total71100.00%2100.00%


static void ieee80211_agg_stop_txq(struct sta_info *sta, int tid) { struct ieee80211_txq *txq = sta->sta.txq[tid]; struct ieee80211_sub_if_data *sdata; struct fq *fq; struct txq_info *txqi; if (!txq) return; txqi = to_txq_info(txq); sdata = vif_to_sdata(txq->vif); fq = &sdata->local->fq; /* Lock here to protect against further seqno updates on dequeue */ spin_lock_bh(&fq->lock); set_bit(IEEE80211_TXQ_STOP, &txqi->flags); spin_unlock_bh(&fq->lock); }

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felix fietkaufelix fietkau7170.30%150.00%
michal kaziormichal kazior3029.70%150.00%
Total101100.00%2100.00%


static void ieee80211_agg_start_txq(struct sta_info *sta, int tid, bool enable) { struct ieee80211_txq *txq = sta->sta.txq[tid]; struct txq_info *txqi; if (!txq) return; txqi = to_txq_info(txq); if (enable) set_bit(IEEE80211_TXQ_AMPDU, &txqi->flags); else clear_bit(IEEE80211_TXQ_AMPDU, &txqi->flags); clear_bit(IEEE80211_TXQ_STOP, &txqi->flags); drv_wake_tx_queue(sta->sdata->local, txqi); }

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felix fietkaufelix fietkau95100.00%1100.00%
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/* * splice packets from the STA's pending to the local pending, * requires a call to ieee80211_agg_splice_finish later */
static void __acquires(agg_queue) ieee80211_agg_splice_packets(struct ieee80211_sub_if_data *sdata, struct tid_ampdu_tx *tid_tx, u16 tid) { struct ieee80211_local *local = sdata->local; int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)]; unsigned long flags; ieee80211_stop_queue_agg(sdata, tid); if (WARN(!tid_tx, "TID %d gone but expected when splicing aggregates from the pending queue\n", tid)) return; if (!skb_queue_empty(&tid_tx->pending)) { spin_lock_irqsave(&local->queue_stop_reason_lock, flags); /* copy over remaining packets */ skb_queue_splice_tail_init(&tid_tx->pending, &local->pending[queue]); spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); } }

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static void __releases(agg_queue) ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid) { ieee80211_wake_queue_agg(sdata, tid); }

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static void ieee80211_remove_tid_tx(struct sta_info *sta, int tid) { struct tid_ampdu_tx *tid_tx; lockdep_assert_held(&sta->ampdu_mlme.mtx); lockdep_assert_held(&sta->lock); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); /* * When we get here, the TX path will not be lockless any more wrt. * aggregation, since the OPERATIONAL bit has long been cleared. * Thus it will block on getting the lock, if it occurs. So if we * stop the queue now, we will not get any more packets, and any * that might be being processed will wait for us here, thereby * guaranteeing that no packets go to the tid_tx pending queue any * more. */ ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid); /* future packets must not find the tid_tx struct any more */ ieee80211_assign_tid_tx(sta, tid, NULL); ieee80211_agg_splice_finish(sta->sdata, tid); ieee80211_agg_start_txq(sta, tid, false); kfree_rcu(tid_tx, rcu_head); }

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johannes bergjohannes berg8490.32%150.00%
felix fietkaufelix fietkau99.68%150.00%
Total93100.00%2100.00%


int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, enum ieee80211_agg_stop_reason reason) { struct ieee80211_local *local = sta->local; struct tid_ampdu_tx *tid_tx; struct ieee80211_ampdu_params params = { .sta = &sta->sta, .tid = tid, .buf_size = 0, .amsdu = false, .timeout = 0, .ssn = 0, }; int ret; lockdep_assert_held(&sta->ampdu_mlme.mtx); switch (reason) { case AGG_STOP_DECLINED: case AGG_STOP_LOCAL_REQUEST: case AGG_STOP_PEER_REQUEST: params.action = IEEE80211_AMPDU_TX_STOP_CONT; break; case AGG_STOP_DESTROY_STA: params.action = IEEE80211_AMPDU_TX_STOP_FLUSH; break; default: WARN_ON_ONCE(1); return -EINVAL; } spin_lock_bh(&sta->lock); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); if (!tid_tx) { spin_unlock_bh(&sta->lock); return -ENOENT; } /* * if we're already stopping ignore any new requests to stop * unless we're destroying it in which case notify the driver */ if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { spin_unlock_bh(&sta->lock); if (reason != AGG_STOP_DESTROY_STA) return -EALREADY; params.action = IEEE80211_AMPDU_TX_STOP_FLUSH_CONT; ret = drv_ampdu_action(local, sta->sdata, &params); WARN_ON_ONCE(ret); return 0; } if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) { /* not even started yet! */ ieee80211_assign_tid_tx(sta, tid, NULL); spin_unlock_bh(&sta->lock); kfree_rcu(tid_tx, rcu_head); return 0; } set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state); spin_unlock_bh(&sta->lock); ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n", sta->sta.addr, tid); del_timer_sync(&tid_tx->addba_resp_timer); del_timer_sync(&tid_tx->session_timer); /* * After this packets are no longer handed right through * to the driver but are put onto tid_tx->pending instead, * with locking to ensure proper access. */ clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state); /* * There might be a few packets being processed right now (on * another CPU) that have already gotten past the aggregation * check when it was still OPERATIONAL and consequently have * IEEE80211_TX_CTL_AMPDU set. In that case, this code might * call into the driver at the same time or even before the * TX paths calls into it, which could confuse the driver. * * Wait for all currently running TX paths to finish before * telling the driver. New packets will not go through since * the aggregation session is no longer OPERATIONAL. */ synchronize_net(); tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ? WLAN_BACK_RECIPIENT : WLAN_BACK_INITIATOR; tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST; ret = drv_ampdu_action(local, sta->sdata, &params); /* HW shall not deny going back to legacy */ if (WARN_ON(ret)) { /* * We may have pending packets get stuck in this case... * Not bothering with a workaround for now. */ } /* * In the case of AGG_STOP_DESTROY_STA, the driver won't * necessarily call ieee80211_stop_tx_ba_cb(), so this may * seem like we can leave the tid_tx data pending forever. * This is true, in a way, but "forever" is only until the * station struct is actually destroyed. In the meantime, * leaving it around ensures that we don't transmit packets * to the driver on this TID which might confuse it. */ return 0; }

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johannes bergjohannes berg31382.59%1878.26%
sara sharonsara sharon5013.19%14.35%
nikolay martynovnikolay martynov82.11%14.35%
emmanuel grumbachemmanuel grumbach41.06%14.35%
lai jiangshanlai jiangshan20.53%14.35%
vasanthakumar thiagarajanvasanthakumar thiagarajan20.53%14.35%
Total379100.00%23100.00%

/* * After sending add Block Ack request we activated a timer until * add Block Ack response will arrive from the recipient. * If this timer expires sta_addba_resp_timer_expired will be executed. */
static void sta_addba_resp_timer_expired(unsigned long data) { /* not an elegant detour, but there is no choice as the timer passes * only one argument, and both sta_info and TID are needed, so init * flow in sta_info_create gives the TID as data, while the timer_to_id * array gives the sta through container_of */ u16 tid = *(u8 *)data; struct sta_info *sta = container_of((void *)data, struct sta_info, timer_to_tid[tid]); struct tid_ampdu_tx *tid_tx; /* check if the TID waits for addBA response */ rcu_read_lock(); tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]); if (!tid_tx || test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { rcu_read_unlock(); ht_dbg(sta->sdata, "timer expired on %pM tid %d but we are not (or no longer) expecting addBA response there\n", sta->sta.addr, tid); return; } ht_dbg(sta->sdata, "addBA response timer expired on %pM tid %d\n", sta->sta.addr, tid); ieee80211_stop_tx_ba_session(&sta->sta, tid); rcu_read_unlock(); }

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void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid) { struct tid_ampdu_tx *tid_tx; struct ieee80211_local *local = sta->local; struct ieee80211_sub_if_data *sdata = sta->sdata; struct ieee80211_ampdu_params params = { .sta = &sta->sta, .action = IEEE80211_AMPDU_TX_START, .tid = tid, .buf_size = 0, .amsdu = false, .timeout = 0, }; int ret; tid_tx = rcu_dereference_protected_tid_tx(sta, tid); /* * Start queuing up packets for this aggregation session. * We're going to release them once the driver is OK with * that. */ clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state); ieee80211_agg_stop_txq(sta, tid); /* * Make sure no packets are being processed. This ensures that * we have a valid starting sequence number and that in-flight * packets have been flushed out and no packets for this TID * will go into the driver during the ampdu_action call. */ synchronize_net(); params.ssn = sta->tid_seq[tid] >> 4; ret = drv_ampdu_action(local, sdata, &params); if (ret) { ht_dbg(sdata, "BA request denied - HW unavailable for %pM tid %d\n", sta->sta.addr, tid); spin_lock_bh(&sta->lock); ieee80211_agg_splice_packets(sdata, tid_tx, tid); ieee80211_assign_tid_tx(sta, tid, NULL); ieee80211_agg_splice_finish(sdata, tid); spin_unlock_bh(&sta->lock); ieee80211_agg_start_txq(sta, tid, false); kfree_rcu(tid_tx, rcu_head); return; } /* activate the timer for the recipient's addBA response */ mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL); ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n", sta->sta.addr, tid); spin_lock_bh(&sta->lock); sta->ampdu_mlme.last_addba_req_time[tid] = jiffies; sta->ampdu_mlme.addba_req_num[tid]++; spin_unlock_bh(&sta->lock); /* send AddBA request */ ieee80211_send_addba_request(sdata, sta->sta.addr, tid, tid_tx->dialog_token, params.ssn, IEEE80211_MAX_AMPDU_BUF, tid_tx->timeout); }

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johannes bergjohannes berg22874.51%857.14%
sara sharonsara sharon4514.71%17.14%
felix fietkaufelix fietkau165.23%17.14%
nikolay martynovnikolay martynov113.59%17.14%
sujith manoharansujith manoharan30.98%17.14%
lai jiangshanlai jiangshan20.65%17.14%
gregory greenmangregory greenman10.33%17.14%
Total306100.00%14100.00%

/* * After accepting the AddBA Response we activated a timer, * resetting it after each frame that we send. */
static void sta_tx_agg_session_timer_expired(unsigned long data) { /* not an elegant detour, but there is no choice as the timer passes * only one argument, and various sta_info are needed here, so init * flow in sta_info_create gives the TID as data, while the timer_to_id * array gives the sta through container_of */ u8 *ptid = (u8 *)data; u8 *timer_to_id = ptid - *ptid; struct sta_info *sta = container_of(timer_to_id, struct sta_info, timer_to_tid[0]); struct tid_ampdu_tx *tid_tx; unsigned long timeout; rcu_read_lock(); tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[*ptid]); if (!tid_tx || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { rcu_read_unlock(); return; } timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout); if (time_is_after_jiffies(timeout)) { mod_timer(&tid_tx->session_timer, timeout); rcu_read_unlock(); return; } rcu_read_unlock(); ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n", sta->sta.addr, (u16)*ptid); ieee80211_stop_tx_ba_session(&sta->sta, *ptid); }

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nikolay martynovnikolay martynov6840.72%120.00%
felix fietkaufelix fietkau5633.53%120.00%
johannes bergjohannes berg4325.75%360.00%
Total167100.00%5100.00%


int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid, u16 timeout) { struct sta_info *sta = container_of(pubsta, struct sta_info, sta); struct ieee80211_sub_if_data *sdata = sta->sdata; struct ieee80211_local *local = sdata->local; struct tid_ampdu_tx *tid_tx; int ret = 0; trace_api_start_tx_ba_session(pubsta, tid); if (WARN(sta->reserved_tid == tid, "Requested to start BA session on reserved tid=%d", tid)) return -EINVAL; if (!pubsta->ht_cap.ht_supported) return -EINVAL; if (WARN_ON_ONCE(!local->ops->ampdu_action)) return -EINVAL; if ((tid >= IEEE80211_NUM_TIDS) || !ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) || ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW)) return -EINVAL; if (WARN_ON(tid >= IEEE80211_FIRST_TSPEC_TSID)) return -EINVAL; ht_dbg(sdata, "Open BA session requested for %pM tid %u\n", pubsta->addr, tid); if (sdata->vif.type != NL80211_IFTYPE_STATION && sdata->vif.type != NL80211_IFTYPE_MESH_POINT && sdata->vif.type != NL80211_IFTYPE_AP_VLAN && sdata->vif.type != NL80211_IFTYPE_AP && sdata->vif.type != NL80211_IFTYPE_ADHOC) return -EINVAL; if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) { ht_dbg(sdata, "BA sessions blocked - Denying BA session request %pM tid %d\n", sta->sta.addr, tid); return -EINVAL; } /* * 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a * member of an IBSS, and has no other existing Block Ack agreement * with the recipient STA, then the initiating STA shall transmit a * Probe Request frame to the recipient STA and shall not transmit an * ADDBA Request frame unless it receives a Probe Response frame * from the recipient within dot11ADDBAFailureTimeout. * * The probe request mechanism for ADDBA is currently not implemented, * but we only build up Block Ack session with HT STAs. This information * is set when we receive a bss info from a probe response or a beacon. */ if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC && !sta->sta.ht_cap.ht_supported) { ht_dbg(sdata, "BA request denied - IBSS STA %pM does not advertise HT support\n", pubsta->addr); return -EINVAL; } spin_lock_bh(&sta->lock); /* we have tried too many times, receiver does not want A-MPDU */ if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) { ret = -EBUSY; goto err_unlock_sta; } /* * if we have tried more than HT_AGG_BURST_RETRIES times we * will spread our requests in time to avoid stalling connection * for too long */ if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES && time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] + HT_AGG_RETRIES_PERIOD)) { ht_dbg(sdata, "BA request denied - waiting a grace period after %d failed requests on %pM tid %u\n", sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid); ret = -EBUSY; goto err_unlock_sta; } tid_tx = rcu_dereference_protected_tid_tx(sta, tid); /* check if the TID is not in aggregation flow already */ if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) { ht_dbg(sdata, "BA request denied - session is not idle on %pM tid %u\n", sta->sta.addr, tid); ret = -EAGAIN; goto err_unlock_sta; } /* prepare A-MPDU MLME for Tx aggregation */ tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC); if (!tid_tx) { ret = -ENOMEM; goto err_unlock_sta; } skb_queue_head_init(&tid_tx->pending); __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state); tid_tx->timeout = timeout; /* response timer */ tid_tx->addba_resp_timer.function = sta_addba_resp_timer_expired; tid_tx->addba_resp_timer.data = (unsigned long)&sta->timer_to_tid[tid]; init_timer(&tid_tx->addba_resp_timer); /* tx timer */ tid_tx->session_timer.function = sta_tx_agg_session_timer_expired; tid_tx->session_timer.data = (unsigned long)&sta->timer_to_tid[tid]; init_timer_deferrable(&tid_tx->session_timer); /* assign a dialog token */ sta->ampdu_mlme.dialog_token_allocator++; tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator; /* * Finally, assign it to the start array; the work item will * collect it and move it to the normal array. */ sta->ampdu_mlme.tid_start_tx[tid] = tid_tx; ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); /* this flow continues off the work */ err_unlock_sta: spin_unlock_bh(&sta->lock); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
johannes bergjohannes berg42569.22%1860.00%
nikolay martynovnikolay martynov8914.50%26.67%
simon wunderlichsimon wunderlich355.70%13.33%
sujith manoharansujith manoharan233.75%26.67%
liad kaufmanliad kaufman193.09%13.33%
thomas pedersenthomas pedersen81.30%13.33%
alexander simonalexander simon81.30%13.33%
arik nemtsovarik nemtsov40.65%13.33%
joe perchesjoe perches10.16%13.33%
chaitanya tkchaitanya tk10.16%13.33%
felix fietkaufelix fietkau10.16%13.33%
Total614100.00%30100.00%

EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
static void ieee80211_agg_tx_operational(struct ieee80211_local *local, struct sta_info *sta, u16 tid) { struct tid_ampdu_tx *tid_tx; struct ieee80211_ampdu_params params = { .sta = &sta->sta, .action