/* * HT handling * * Copyright 2003, Jouni Malinen * Copyright 2002-2005, Instant802 Networks, Inc. * Copyright 2005-2006, Devicescape Software, Inc. * Copyright 2006-2007 Jiri Benc * Copyright 2007, Michael Wu * Copyright 2007-2010, Intel Corporation * Copyright(c) 2015-2017 Intel Deutschland GmbH * Copyright (C) 2018 - 2019 Intel Corporation * * 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 #include #include #include #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 = skb_put_zero(skb, 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_tid(sdata, skb, tid); } 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 = skb_put_zero(skb, 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); } 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); } /* * 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); } 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); } 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); } 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); local_bh_disable(); rcu_read_lock(); drv_wake_tx_queue(sta->sdata->local, txqi); rcu_read_unlock(); local_bh_enable(); } /* * 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); } } static void __releases(agg_queue) ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid) { ieee80211_wake_queue_agg(sdata, tid); } 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); } 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); /* free struct pending for start, if present */ tid_tx = sta->ampdu_mlme.tid_start_tx[tid]; kfree(tid_tx); sta->ampdu_mlme.tid_start_tx[tid] = NULL; 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, ¶ms); 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); ieee80211_agg_stop_txq(sta, tid); 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. */ if (!local->in_reconfig) 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, ¶ms); /* 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; } /* * 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(struct timer_list *t) { struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, addba_resp_timer); struct sta_info *sta = tid_tx->sta; u8 tid = tid_tx->tid; /* check if the TID waits for addBA response */ if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { ht_dbg(sta->sdata, "timer expired on %pM tid %d not expecting addBA response\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); } 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; u16 buf_size; 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, ¶ms); 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); if (sta->sta.he_cap.has_he) { buf_size = local->hw.max_tx_aggregation_subframes; } else { /* * We really should use what the driver told us it will * transmit as the maximum, but certain APs (e.g. the * LinkSys WRT120N with FW v1.0.07 build 002 Jun 18 2012) * will crash when we use a lower number. */ buf_size = IEEE80211_MAX_AMPDU_BUF_HT; } /* send AddBA request */ ieee80211_send_addba_request(sdata, sta->sta.addr, tid, tid_tx->dialog_token, params.ssn, buf_size, tid_tx->timeout); } /* * 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(struct timer_list *t) { struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, session_timer); struct sta_info *sta = tid_tx->sta; u8 tid = tid_tx->tid; unsigned long timeout; if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { 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); return; } ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n", sta->sta.addr, tid); ieee80211_stop_tx_ba_session(&sta->sta, tid); } 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 - %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; tid_tx->sta = sta; tid_tx->tid = tid; /* response timer */ timer_setup(&tid_tx->addba_resp_timer, sta_addba_resp_timer_expired, 0); /* tx timer */ timer_setup(&tid_tx->session_timer, sta_tx_agg_session_timer_expired, TIMER_DEFERRABLE); /* 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; } 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 = IEEE80211_AMPDU_TX_OPERATIONAL, .tid = tid, .timeout = 0, .ssn = 0, }; lockdep_assert_held(&sta->ampdu_mlme.mtx); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); params.buf_size = tid_tx->buf_size; params.amsdu = tid_tx->amsdu; ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n", sta->sta.addr, tid); drv_ampdu_action(local, sta->sdata, ¶ms); /* * synchronize with TX path, while splicing the TX path * should block so it won't put more packets onto pending. */ spin_lock_bh(&sta->lock); ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid); /* * Now mark as operational. This will be visible * in the TX path, and lets it go lock-free in * the common case. */ set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state); ieee80211_agg_splice_finish(sta->sdata, tid); spin_unlock_bh(&sta->lock); ieee80211_agg_start_txq(sta, tid, true); } void ieee80211_start_tx_ba_cb(struct sta_info *sta, int tid, struct tid_ampdu_tx *tid_tx) { struct ieee80211_sub_if_data *sdata = sta->sdata; struct ieee80211_local *local = sdata->local; if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))) return; if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) ieee80211_agg_tx_operational(local, sta, tid); } static struct tid_ampdu_tx * ieee80211_lookup_tid_tx(struct ieee80211_sub_if_data *sdata, const u8 *ra, u16 tid, struct sta_info **sta) { struct tid_ampdu_tx *tid_tx; if (tid >= IEEE80211_NUM_TIDS) { ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n", tid, IEEE80211_NUM_TIDS); return NULL; } *sta = sta_info_get_bss(sdata, ra); if (!*sta) { ht_dbg(sdata, "Could not find station: %pM\n", ra); return NULL; } tid_tx = rcu_dereference((*sta)->ampdu_mlme.tid_tx[tid]); if (WARN_ON(!tid_tx)) ht_dbg(sdata, "addBA was not requested!\n"); return tid_tx; } void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif, const u8 *ra, u16 tid) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); struct ieee80211_local *local = sdata->local; struct sta_info *sta; struct tid_ampdu_tx *tid_tx; trace_api_start_tx_ba_cb(sdata, ra, tid); rcu_read_lock(); tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta); if (!tid_tx) goto out; set_bit(HT_AGG_STATE_START_CB, &tid_tx->state); ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); out: rcu_read_unlock(); } EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe); int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid, enum ieee80211_agg_stop_reason reason) { int ret; mutex_lock(&sta->ampdu_mlme.mtx); ret = ___ieee80211_stop_tx_ba_session(sta, tid, reason); mutex_unlock(&sta->ampdu_mlme.mtx); return ret; } int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid) { 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_stop_tx_ba_session(pubsta, tid); if (!local->ops->ampdu_action) return -EINVAL; if (tid >= IEEE80211_NUM_TIDS) return -EINVAL; spin_lock_bh(&sta->lock); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); if (!tid_tx) { ret = -ENOENT; goto unlock; } WARN(sta->reserved_tid == tid, "Requested to stop BA session on reserved tid=%d", tid); if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { /* already in progress stopping it */ ret = 0; goto unlock; } set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state); ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); unlock: spin_unlock_bh(&sta->lock); return ret; } EXPORT_SYMBOL(ieee80211_stop_tx_ba_session); void ieee80211_stop_tx_ba_cb(struct sta_info *sta, int tid, struct tid_ampdu_tx *tid_tx) { struct ieee80211_sub_if_data *sdata = sta->sdata; bool send_delba = false; ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n", sta->sta.addr, tid); spin_lock_bh(&sta->lock); if (!test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { ht_dbg(sdata, "unexpected callback to A-MPDU stop for %pM tid %d\n", sta->sta.addr, tid); goto unlock_sta; } if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop) send_delba = true; ieee80211_remove_tid_tx(sta, tid); unlock_sta: spin_unlock_bh(&sta->lock); if (send_delba) ieee80211_send_delba(sdata, sta->sta.addr, tid, WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE); } void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif, const u8 *ra, u16 tid) { struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif); struct ieee80211_local *local = sdata->local; struct sta_info *sta; struct tid_ampdu_tx *tid_tx; trace_api_stop_tx_ba_cb(sdata, ra, tid); rcu_read_lock(); tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta); if (!tid_tx) goto out; set_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state); ieee80211_queue_work(&local->hw, &sta->ampdu_mlme.work); out: rcu_read_unlock(); } EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe); void ieee80211_process_addba_resp(struct ieee80211_local *local, struct sta_info *sta, struct ieee80211_mgmt *mgmt, size_t len) { struct tid_ampdu_tx *tid_tx; struct ieee80211_txq *txq; u16 capab, tid, buf_size; bool amsdu; capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab); amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK; tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2; buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6; buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes); txq = sta->sta.txq[tid]; if (!amsdu && txq) set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags); mutex_lock(&sta->ampdu_mlme.mtx); tid_tx = rcu_dereference_protected_tid_tx(sta, tid); if (!tid_tx) goto out; if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) { ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n", sta->sta.addr, tid); goto out; } del_timer_sync(&tid_tx->addba_resp_timer); ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n", sta->sta.addr, tid); /* * addba_resp_timer may have fired before we got here, and * caused WANT_STOP to be set. If the stop then was already * processed further, STOPPING might be set. */ if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) { ht_dbg(sta->sdata, "got addBA resp for %pM tid %d but we already gave up\n", sta->sta.addr, tid); goto out; } /* * IEEE 802.11-2007 7.3.1.14: * In an ADDBA Response frame, when the Status Code field * is set to 0, the Buffer Size subfield is set to a value * of at least 1. */ if (le16_to_cpu(mgmt->u.action.u.addba_resp.status) == WLAN_STATUS_SUCCESS && buf_size) { if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) { /* ignore duplicate response */ goto out; } tid_tx->buf_size = buf_size; tid_tx->amsdu = amsdu; if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)) ieee80211_agg_tx_operational(local, sta, tid); sta->ampdu_mlme.addba_req_num[tid] = 0; tid_tx->timeout = le16_to_cpu(mgmt->u.action.u.addba_resp.timeout); if (tid_tx->timeout) { mod_timer(&tid_tx->session_timer, TU_TO_EXP_TIME(tid_tx->timeout)); tid_tx->last_tx = jiffies; } } else { ___ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED); } out: mutex_unlock(&sta->ampdu_mlme.mtx); }