[deliverable/linux.git] / net / mac80211 / agg-tx.c

/*
 * 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 2007-2009, 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 <linux/ieee80211.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "wme.h"

/**
 * DOC: TX aggregation
 *
 * Aggregation on the TX side requires setting the hardware flag
 * %IEEE80211_HW_AMPDU_AGGREGATION as well as, if present, the @ampdu_queues
 * hardware parameter to the number of hardware AMPDU queues. If there are no
 * hardware queues then the driver will (currently) have to do all frame
 * buffering.
 *
 * 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() (or ieee80211_start_tx_ba_cb_irqsafe())
 * function, which will start the aggregation session.
 *
 * Similarly, when the aggregation session is stopped by
 * 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()
 * (or ieee80211_stop_tx_ba_cb_irqsafe()).
 */

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 ieee80211_if_sta *ifsta = &sdata->u.sta;
	struct sk_buff *skb;
	struct ieee80211_mgmt *mgmt;
	u16 capab;

	skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);

	if (!skb) {
		printk(KERN_ERR "%s: failed to allocate buffer "
				"for addba request frame\n", sdata->dev->name);
		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->dev->dev_addr, ETH_ALEN);
	if (sdata->vif.type == NL80211_IFTYPE_AP ||
	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
		memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
	else
		memcpy(mgmt->bssid, ifsta->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 << 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, 1);
}

void ieee80211_send_bar(struct ieee80211_sub_if_data *sdata, u8 *ra, u16 tid, u16 ssn)
{
	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) {
		printk(KERN_ERR "%s: failed to allocate buffer for "
			"bar frame\n", sdata->dev->name);
		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->dev->dev_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 << 12);
	bar->control = cpu_to_le16(bar_control);
	bar->start_seq_num = cpu_to_le16(ssn);

	ieee80211_tx_skb(sdata, skb, 0);
}

static int __ieee80211_stop_tx_ba_session(struct ieee80211_local *local,
					  struct sta_info *sta, u16 tid,
					  enum ieee80211_back_parties initiator)
{
	int ret;
	u8 *state;

	state = &sta->ampdu_mlme.tid_state_tx[tid];

	if (local->hw.ampdu_queues)
		ieee80211_stop_queue(&local->hw, sta->tid_to_tx_q[tid]);

	*state = HT_AGG_STATE_REQ_STOP_BA_MSK |
		(initiator << HT_AGG_STATE_INITIATOR_SHIFT);

	ret = local->ops->ampdu_action(&local->hw, IEEE80211_AMPDU_TX_STOP,
				       &sta->sta, tid, NULL);

	/* HW shall not deny going back to legacy */
	if (WARN_ON(ret)) {
		*state = HT_AGG_STATE_OPERATIONAL;
		if (local->hw.ampdu_queues)
			ieee80211_wake_queue(&local->hw, sta->tid_to_tx_q[tid]);
	}

	return ret;
}

/*
 * 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 ieee80211_local *local = sta->local;
	u8 *state;

	state = &sta->ampdu_mlme.tid_state_tx[tid];

	/* check if the TID waits for addBA response */
	spin_lock_bh(&sta->lock);
	if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
		spin_unlock_bh(&sta->lock);
		*state = HT_AGG_STATE_IDLE;
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "timer expired on tid %d but we are not "
				"expecting addBA response there", tid);
#endif
		return;
	}

#ifdef CONFIG_MAC80211_HT_DEBUG
	printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
#endif

	__ieee80211_stop_tx_ba_session(local, sta, tid, WLAN_BACK_INITIATOR);
	spin_unlock_bh(&sta->lock);
}

int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct sta_info *sta;
	struct ieee80211_sub_if_data *sdata;
	u16 start_seq_num;
	u8 *state;
	int ret = 0;

	if (WARN_ON(!local->ops->ampdu_action))
		return -EINVAL;

	if ((tid >= STA_TID_NUM) || !(hw->flags & IEEE80211_HW_AMPDU_AGGREGATION))
		return -EINVAL;

#ifdef CONFIG_MAC80211_HT_DEBUG
	printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
	       ra, tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */

	rcu_read_lock();

	sta = sta_info_get(local, ra);
	if (!sta) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "Could not find the station\n");
#endif
		ret = -ENOENT;
		goto exit;
	}

	/*
	 * The aggregation code is not prepared to handle
	 * anything but STA/AP due to the BSSID handling.
	 * IBSS could work in the code but isn't supported
	 * by drivers or the standard.
	 */
	if (sta->sdata->vif.type != NL80211_IFTYPE_STATION &&
	    sta->sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
	    sta->sdata->vif.type != NL80211_IFTYPE_AP) {
		ret = -EINVAL;
		goto exit;
	}

	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;
	}

	state = &sta->ampdu_mlme.tid_state_tx[tid];
	/* check if the TID is not in aggregation flow already */
	if (*state != HT_AGG_STATE_IDLE) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "BA request denied - session is not "
				 "idle on tid %u\n", tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
		ret = -EAGAIN;
		goto err_unlock_sta;
	}

	/* prepare A-MPDU MLME for Tx aggregation */
	sta->ampdu_mlme.tid_tx[tid] =
			kmalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
	if (!sta->ampdu_mlme.tid_tx[tid]) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		if (net_ratelimit())
			printk(KERN_ERR "allocate tx mlme to tid %d failed\n",
					tid);
#endif
		ret = -ENOMEM;
		goto err_unlock_sta;
	}
	/* Tx timer */
	sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.function =
			sta_addba_resp_timer_expired;
	sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.data =
			(unsigned long)&sta->timer_to_tid[tid];
	init_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);

	if (hw->ampdu_queues) {
		/* create a new queue for this aggregation */
		ret = ieee80211_ht_agg_queue_add(local, sta, tid);

		/* case no queue is available to aggregation
		 * don't switch to aggregation */
		if (ret) {
#ifdef CONFIG_MAC80211_HT_DEBUG
			printk(KERN_DEBUG "BA request denied - "
			       "queue unavailable for tid %d\n", tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
			goto err_unlock_queue;
		}
	}
	sdata = sta->sdata;

	/* Ok, the Addba frame hasn't been sent yet, but if the driver calls the
	 * call back right away, it must see that the flow has begun */
	*state |= HT_ADDBA_REQUESTED_MSK;

	/* This is slightly racy because the queue isn't stopped */
	start_seq_num = sta->tid_seq[tid];

	ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_TX_START,
				       &sta->sta, tid, &start_seq_num);

	if (ret) {
		/* No need to requeue the packets in the agg queue, since we
		 * held the tx lock: no packet could be enqueued to the newly
		 * allocated queue */
		if (hw->ampdu_queues)
			ieee80211_ht_agg_queue_remove(local, sta, tid, 0);
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "BA request denied - HW unavailable for"
					" tid %d\n", tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
		*state = HT_AGG_STATE_IDLE;
		goto err_unlock_queue;
	}

	/* Will put all the packets in the new SW queue */
	if (hw->ampdu_queues)
		ieee80211_requeue(local, ieee802_1d_to_ac[tid]);
	spin_unlock_bh(&sta->lock);

	/* send an addBA request */
	sta->ampdu_mlme.dialog_token_allocator++;
	sta->ampdu_mlme.tid_tx[tid]->dialog_token =
			sta->ampdu_mlme.dialog_token_allocator;
	sta->ampdu_mlme.tid_tx[tid]->ssn = start_seq_num;


	ieee80211_send_addba_request(sta->sdata, ra, tid,
			 sta->ampdu_mlme.tid_tx[tid]->dialog_token,
			 sta->ampdu_mlme.tid_tx[tid]->ssn,
			 0x40, 5000);
	/* activate the timer for the recipient's addBA response */
	sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.expires =
				jiffies + ADDBA_RESP_INTERVAL;
	add_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
#ifdef CONFIG_MAC80211_HT_DEBUG
	printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
#endif
	goto exit;

err_unlock_queue:
	kfree(sta->ampdu_mlme.tid_tx[tid]);
	sta->ampdu_mlme.tid_tx[tid] = NULL;
	ret = -EBUSY;
err_unlock_sta:
	spin_unlock_bh(&sta->lock);
exit:
	rcu_read_unlock();
	return ret;
}
EXPORT_SYMBOL(ieee80211_start_tx_ba_session);

void ieee80211_start_tx_ba_cb(struct ieee80211_hw *hw, u8 *ra, u16 tid)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct sta_info *sta;
	u8 *state;

	if (tid >= STA_TID_NUM) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
				tid, STA_TID_NUM);
#endif
		return;
	}

	rcu_read_lock();
	sta = sta_info_get(local, ra);
	if (!sta) {
		rcu_read_unlock();
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "Could not find station: %pM\n", ra);
#endif
		return;
	}

	state = &sta->ampdu_mlme.tid_state_tx[tid];
	spin_lock_bh(&sta->lock);

	if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "addBA was not requested yet, state is %d\n",
				*state);
#endif
		spin_unlock_bh(&sta->lock);
		rcu_read_unlock();
		return;
	}

	WARN_ON_ONCE(*state & HT_ADDBA_DRV_READY_MSK);

	*state |= HT_ADDBA_DRV_READY_MSK;

	if (*state == HT_AGG_STATE_OPERATIONAL) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "Aggregation is on for tid %d \n", tid);
#endif
		if (hw->ampdu_queues)
			ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);
	}
	spin_unlock_bh(&sta->lock);
	rcu_read_unlock();
}
EXPORT_SYMBOL(ieee80211_start_tx_ba_cb);

void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
				      const u8 *ra, u16 tid)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct ieee80211_ra_tid *ra_tid;
	struct sk_buff *skb = dev_alloc_skb(0);

	if (unlikely(!skb)) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		if (net_ratelimit())
			printk(KERN_WARNING "%s: Not enough memory, "
			       "dropping start BA session", skb->dev->name);
#endif
		return;
	}
	ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
	memcpy(&ra_tid->ra, ra, ETH_ALEN);
	ra_tid->tid = tid;

	skb->pkt_type = IEEE80211_ADDBA_MSG;
	skb_queue_tail(&local->skb_queue, skb);
	tasklet_schedule(&local->tasklet);
}
EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);


int ieee80211_stop_tx_ba_session(struct ieee80211_hw *hw,
				 u8 *ra, u16 tid,
				 enum ieee80211_back_parties initiator)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct sta_info *sta;
	u8 *state;
	int ret = 0;

	if (WARN_ON(!local->ops->ampdu_action))
		return -EINVAL;

	if (tid >= STA_TID_NUM)
		return -EINVAL;

	rcu_read_lock();
	sta = sta_info_get(local, ra);
	if (!sta) {
		rcu_read_unlock();
		return -ENOENT;
	}

	/* check if the TID is in aggregation */
	state = &sta->ampdu_mlme.tid_state_tx[tid];
	spin_lock_bh(&sta->lock);

	if (*state != HT_AGG_STATE_OPERATIONAL) {
		ret = -ENOENT;
		goto unlock;
	}

#ifdef CONFIG_MAC80211_HT_DEBUG
	printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
	       ra, tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */

	ret = __ieee80211_stop_tx_ba_session(local, sta, tid, initiator);

 unlock:
	spin_unlock_bh(&sta->lock);

	rcu_read_unlock();

	return ret;
}
EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);

void ieee80211_stop_tx_ba_cb(struct ieee80211_hw *hw, u8 *ra, u8 tid)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct sta_info *sta;
	u8 *state;
	int agg_queue;

	if (tid >= STA_TID_NUM) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
				tid, STA_TID_NUM);
#endif
		return;
	}

#ifdef CONFIG_MAC80211_HT_DEBUG
	printk(KERN_DEBUG "Stopping Tx BA session for %pM tid %d\n",
	       ra, tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */

	rcu_read_lock();
	sta = sta_info_get(local, ra);
	if (!sta) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "Could not find station: %pM\n", ra);
#endif
		rcu_read_unlock();
		return;
	}
	state = &sta->ampdu_mlme.tid_state_tx[tid];

	/* NOTE: no need to use sta->lock in this state check, as
	 * ieee80211_stop_tx_ba_session will let only one stop call to
	 * pass through per sta/tid
	 */
	if ((*state & HT_AGG_STATE_REQ_STOP_BA_MSK) == 0) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
#endif
		rcu_read_unlock();
		return;
	}

	if (*state & HT_AGG_STATE_INITIATOR_MSK)
		ieee80211_send_delba(sta->sdata, ra, tid,
			WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);

	if (hw->ampdu_queues) {
		agg_queue = sta->tid_to_tx_q[tid];
		ieee80211_ht_agg_queue_remove(local, sta, tid, 1);

		/* We just requeued the all the frames that were in the
		 * removed queue, and since we might miss a softirq we do
		 * netif_schedule_queue.  ieee80211_wake_queue is not used
		 * here as this queue is not necessarily stopped
		 */
		netif_schedule_queue(netdev_get_tx_queue(local->mdev,
							 agg_queue));
	}
	spin_lock_bh(&sta->lock);
	*state = HT_AGG_STATE_IDLE;
	sta->ampdu_mlme.addba_req_num[tid] = 0;
	kfree(sta->ampdu_mlme.tid_tx[tid]);
	sta->ampdu_mlme.tid_tx[tid] = NULL;
	spin_unlock_bh(&sta->lock);

	rcu_read_unlock();
}
EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb);

void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
				     const u8 *ra, u16 tid)
{
	struct ieee80211_local *local = hw_to_local(hw);
	struct ieee80211_ra_tid *ra_tid;
	struct sk_buff *skb = dev_alloc_skb(0);

	if (unlikely(!skb)) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		if (net_ratelimit())
			printk(KERN_WARNING "%s: Not enough memory, "
			       "dropping stop BA session", skb->dev->name);
#endif
		return;
	}
	ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
	memcpy(&ra_tid->ra, ra, ETH_ALEN);
	ra_tid->tid = tid;

	skb->pkt_type = IEEE80211_DELBA_MSG;
	skb_queue_tail(&local->skb_queue, skb);
	tasklet_schedule(&local->tasklet);
}
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 ieee80211_hw *hw = &local->hw;
	u16 capab;
	u16 tid, start_seq_num;
	u8 *state;

	capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
	tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;

	state = &sta->ampdu_mlme.tid_state_tx[tid];

	spin_lock_bh(&sta->lock);

	if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
		spin_unlock_bh(&sta->lock);
		return;
	}

	if (mgmt->u.action.u.addba_resp.dialog_token !=
		sta->ampdu_mlme.tid_tx[tid]->dialog_token) {
		spin_unlock_bh(&sta->lock);
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
		return;
	}

	del_timer_sync(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
#ifdef CONFIG_MAC80211_HT_DEBUG
	printk(KERN_DEBUG "switched off addBA timer for tid %d \n", tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
	if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
			== WLAN_STATUS_SUCCESS) {
		*state |= HT_ADDBA_RECEIVED_MSK;
		sta->ampdu_mlme.addba_req_num[tid] = 0;

		if (*state == HT_AGG_STATE_OPERATIONAL &&
		    local->hw.ampdu_queues)
			ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);

		if (local->ops->ampdu_action) {
			(void)local->ops->ampdu_action(hw,
					       IEEE80211_AMPDU_TX_RESUME,
					       &sta->sta, tid, &start_seq_num);
		}
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "Resuming TX aggregation for tid %d\n", tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
		spin_unlock_bh(&sta->lock);
	} else {
		sta->ampdu_mlme.addba_req_num[tid]++;
		__ieee80211_stop_tx_ba_session(local, sta, tid,
					       WLAN_BACK_INITIATOR);
		spin_unlock_bh(&sta->lock);
	}
}
Commit	Line	Data
b8695a8f JB	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 2007-2009, Intel Corporation
	10	*
	11	* This program is free software; you can redistribute it and/or modify
	12	* it under the terms of the GNU General Public License version 2 as
	13	* published by the Free Software Foundation.
	14	*/
	15
	16	#include <linux/ieee80211.h>
	17	#include <net/mac80211.h>
	18	#include "ieee80211_i.h"
	19	#include "wme.h"
	20
86ab6c5a JB	21	/**
	22	* DOC: TX aggregation
	23	*
	24	* Aggregation on the TX side requires setting the hardware flag
	25	* %IEEE80211_HW_AMPDU_AGGREGATION as well as, if present, the @ampdu_queues
	26	* hardware parameter to the number of hardware AMPDU queues. If there are no
	27	* hardware queues then the driver will (currently) have to do all frame
	28	* buffering.
	29	*
	30	* When TX aggregation is started by some subsystem (usually the rate control
	31	* algorithm would be appropriate) by calling the
	32	* ieee80211_start_tx_ba_session() function, the driver will be notified via
	33	* its @ampdu_action function, with the %IEEE80211_AMPDU_TX_START action.
	34	*
	35	* In response to that, the driver is later required to call the
	36	* ieee80211_start_tx_ba_cb() (or ieee80211_start_tx_ba_cb_irqsafe())
	37	* function, which will start the aggregation session.
	38	*
	39	* Similarly, when the aggregation session is stopped by
	40	* ieee80211_stop_tx_ba_session(), the driver's @ampdu_action function will
	41	* be called with the action %IEEE80211_AMPDU_TX_STOP. In this case, the
	42	* call must not fail, and the driver must later call ieee80211_stop_tx_ba_cb()
	43	* (or ieee80211_stop_tx_ba_cb_irqsafe()).
	44	*/
	45
b8695a8f JB	46	static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
	47	const u8 *da, u16 tid,
	48	u8 dialog_token, u16 start_seq_num,
	49	u16 agg_size, u16 timeout)
	50	{
	51	struct ieee80211_local *local = sdata->local;
	52	struct ieee80211_if_sta *ifsta = &sdata->u.sta;
	53	struct sk_buff *skb;
	54	struct ieee80211_mgmt *mgmt;
	55	u16 capab;
	56
	57	skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
	58
	59	if (!skb) {
	60	printk(KERN_ERR "%s: failed to allocate buffer "
	61	"for addba request frame\n", sdata->dev->name);
	62	return;
	63	}
	64	skb_reserve(skb, local->hw.extra_tx_headroom);
	65	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
	66	memset(mgmt, 0, 24);
	67	memcpy(mgmt->da, da, ETH_ALEN);
	68	memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
8abd3f9b JB	69	if (sdata->vif.type == NL80211_IFTYPE_AP \|\|
8abd3f9b JB	70	sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
b8695a8f JB	71	memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
	72	else
	73	memcpy(mgmt->bssid, ifsta->bssid, ETH_ALEN);
	74
	75	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT \|
	76	IEEE80211_STYPE_ACTION);
	77
	78	skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
	79
	80	mgmt->u.action.category = WLAN_CATEGORY_BACK;
	81	mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
	82
	83	mgmt->u.action.u.addba_req.dialog_token = dialog_token;
	84	capab = (u16)(1 << 1); /* bit 1 aggregation policy */
	85	capab \|= (u16)(tid << 2); /* bit 5:2 TID number */
	86	capab \|= (u16)(agg_size << 6); /* bit 15:6 max size of aggergation */
	87
	88	mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
	89
	90	mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
	91	mgmt->u.action.u.addba_req.start_seq_num =
	92	cpu_to_le16(start_seq_num << 4);
	93
	94	ieee80211_tx_skb(sdata, skb, 1);
	95	}
	96
	97	void ieee80211_send_bar(struct ieee80211_sub_if_data sdata, u8 ra, u16 tid, u16 ssn)
	98	{
	99	struct ieee80211_local *local = sdata->local;
	100	struct sk_buff *skb;
	101	struct ieee80211_bar *bar;
	102	u16 bar_control = 0;
	103
	104	skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
	105	if (!skb) {
	106	printk(KERN_ERR "%s: failed to allocate buffer for "
	107	"bar frame\n", sdata->dev->name);
	108	return;
	109	}
	110	skb_reserve(skb, local->hw.extra_tx_headroom);
	111	bar = (struct ieee80211_bar )skb_put(skb, sizeof(bar));
	112	memset(bar, 0, sizeof(*bar));
	113	bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL \|
	114	IEEE80211_STYPE_BACK_REQ);
	115	memcpy(bar->ra, ra, ETH_ALEN);
	116	memcpy(bar->ta, sdata->dev->dev_addr, ETH_ALEN);
	117	bar_control \|= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
	118	bar_control \|= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
	119	bar_control \|= (u16)(tid << 12);
	120	bar->control = cpu_to_le16(bar_control);
	121	bar->start_seq_num = cpu_to_le16(ssn);
	122
	123	ieee80211_tx_skb(sdata, skb, 0);
	124	}
	125
23e6a7ea JB	126	static int __ieee80211_stop_tx_ba_session(struct ieee80211_local *local,
	127	struct sta_info *sta, u16 tid,
	128	enum ieee80211_back_parties initiator)
	129	{
	130	int ret;
	131	u8 *state;
	132
	133	state = &sta->ampdu_mlme.tid_state_tx[tid];
	134
	135	if (local->hw.ampdu_queues)
	136	ieee80211_stop_queue(&local->hw, sta->tid_to_tx_q[tid]);
	137
	138	*state = HT_AGG_STATE_REQ_STOP_BA_MSK \|
	139	(initiator << HT_AGG_STATE_INITIATOR_SHIFT);
	140
	141	ret = local->ops->ampdu_action(&local->hw, IEEE80211_AMPDU_TX_STOP,
	142	&sta->sta, tid, NULL);
	143
	144	/* HW shall not deny going back to legacy */
	145	if (WARN_ON(ret)) {
	146	*state = HT_AGG_STATE_OPERATIONAL;
	147	if (local->hw.ampdu_queues)
	148	ieee80211_wake_queue(&local->hw, sta->tid_to_tx_q[tid]);
	149	}
	150
	151	return ret;
	152	}
	153
b8695a8f JB	154	/*
	155	* After sending add Block Ack request we activated a timer until
	156	* add Block Ack response will arrive from the recipient.
	157	* If this timer expires sta_addba_resp_timer_expired will be executed.
	158	*/
	159	static void sta_addba_resp_timer_expired(unsigned long data)
	160	{
	161	/* not an elegant detour, but there is no choice as the timer passes
	162	* only one argument, and both sta_info and TID are needed, so init
	163	* flow in sta_info_create gives the TID as data, while the timer_to_id
	164	* array gives the sta through container_of */
	165	u16 tid = (u8 )data;
23e6a7ea	166	struct sta_info sta = container_of((void )data,
b8695a8f	167	struct sta_info, timer_to_tid[tid]);
23e6a7ea	168	struct ieee80211_local *local = sta->local;
b8695a8f JB	169	u8 *state;
b8695a8f JB	170
b8695a8f	171	state = &sta->ampdu_mlme.tid_state_tx[tid];
23e6a7ea	172
b8695a8f JB	173	/* check if the TID waits for addBA response */
	174	spin_lock_bh(&sta->lock);
	175	if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
	176	spin_unlock_bh(&sta->lock);
	177	*state = HT_AGG_STATE_IDLE;
	178	#ifdef CONFIG_MAC80211_HT_DEBUG
	179	printk(KERN_DEBUG "timer expired on tid %d but we are not "
	180	"expecting addBA response there", tid);
	181	#endif
23e6a7ea	182	return;
b8695a8f JB	183	}
	184
	185	#ifdef CONFIG_MAC80211_HT_DEBUG
	186	printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
	187	#endif
	188
23e6a7ea	189	__ieee80211_stop_tx_ba_session(local, sta, tid, WLAN_BACK_INITIATOR);
b8695a8f	190	spin_unlock_bh(&sta->lock);
b8695a8f JB	191	}
	192
	193	int ieee80211_start_tx_ba_session(struct ieee80211_hw hw, u8 ra, u16 tid)
	194	{
	195	struct ieee80211_local *local = hw_to_local(hw);
	196	struct sta_info *sta;
	197	struct ieee80211_sub_if_data *sdata;
	198	u16 start_seq_num;
	199	u8 *state;
	200	int ret = 0;
	201
23e6a7ea JB	202	if (WARN_ON(!local->ops->ampdu_action))
	203	return -EINVAL;
	204
b8695a8f JB	205	if ((tid >= STA_TID_NUM) \|\| !(hw->flags & IEEE80211_HW_AMPDU_AGGREGATION))
	206	return -EINVAL;
	207
	208	#ifdef CONFIG_MAC80211_HT_DEBUG
	209	printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
	210	ra, tid);
	211	#endif /* CONFIG_MAC80211_HT_DEBUG */
	212
	213	rcu_read_lock();
	214
	215	sta = sta_info_get(local, ra);
	216	if (!sta) {
	217	#ifdef CONFIG_MAC80211_HT_DEBUG
	218	printk(KERN_DEBUG "Could not find the station\n");
	219	#endif
	220	ret = -ENOENT;
	221	goto exit;
	222	}
	223
8abd3f9b JB	224	/*
	225	* The aggregation code is not prepared to handle
	226	* anything but STA/AP due to the BSSID handling.
	227	* IBSS could work in the code but isn't supported
	228	* by drivers or the standard.
	229	*/
	230	if (sta->sdata->vif.type != NL80211_IFTYPE_STATION &&
	231	sta->sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
	232	sta->sdata->vif.type != NL80211_IFTYPE_AP) {
	233	ret = -EINVAL;
	234	goto exit;
	235	}
	236
b8695a8f JB	237	spin_lock_bh(&sta->lock);
	238
	239	/* we have tried too many times, receiver does not want A-MPDU */
	240	if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
	241	ret = -EBUSY;
	242	goto err_unlock_sta;
	243	}
	244
	245	state = &sta->ampdu_mlme.tid_state_tx[tid];
	246	/* check if the TID is not in aggregation flow already */
	247	if (*state != HT_AGG_STATE_IDLE) {
	248	#ifdef CONFIG_MAC80211_HT_DEBUG
	249	printk(KERN_DEBUG "BA request denied - session is not "
	250	"idle on tid %u\n", tid);
	251	#endif /* CONFIG_MAC80211_HT_DEBUG */
	252	ret = -EAGAIN;
	253	goto err_unlock_sta;
	254	}
	255
	256	/* prepare A-MPDU MLME for Tx aggregation */
	257	sta->ampdu_mlme.tid_tx[tid] =
	258	kmalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
	259	if (!sta->ampdu_mlme.tid_tx[tid]) {
	260	#ifdef CONFIG_MAC80211_HT_DEBUG
	261	if (net_ratelimit())
	262	printk(KERN_ERR "allocate tx mlme to tid %d failed\n",
	263	tid);
	264	#endif
	265	ret = -ENOMEM;
	266	goto err_unlock_sta;
	267	}
	268	/* Tx timer */
	269	sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.function =
	270	sta_addba_resp_timer_expired;
	271	sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.data =
	272	(unsigned long)&sta->timer_to_tid[tid];
	273	init_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
	274
	275	if (hw->ampdu_queues) {
	276	/* create a new queue for this aggregation */
	277	ret = ieee80211_ht_agg_queue_add(local, sta, tid);
	278
	279	/* case no queue is available to aggregation
	280	* don't switch to aggregation */
	281	if (ret) {
	282	#ifdef CONFIG_MAC80211_HT_DEBUG
	283	printk(KERN_DEBUG "BA request denied - "
	284	"queue unavailable for tid %d\n", tid);
	285	#endif /* CONFIG_MAC80211_HT_DEBUG */
	286	goto err_unlock_queue;
	287	}
	288	}
	289	sdata = sta->sdata;
	290
	291	/* Ok, the Addba frame hasn't been sent yet, but if the driver calls the
	292	* call back right away, it must see that the flow has begun */
	293	*state \|= HT_ADDBA_REQUESTED_MSK;
	294
	295	/* This is slightly racy because the queue isn't stopped */
	296	start_seq_num = sta->tid_seq[tid];
	297
23e6a7ea JB	298	ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_TX_START,
23e6a7ea JB	299	&sta->sta, tid, &start_seq_num);
b8695a8f JB	300
	301	if (ret) {
	302	/* No need to requeue the packets in the agg queue, since we
	303	* held the tx lock: no packet could be enqueued to the newly
	304	* allocated queue */
	305	if (hw->ampdu_queues)
	306	ieee80211_ht_agg_queue_remove(local, sta, tid, 0);
	307	#ifdef CONFIG_MAC80211_HT_DEBUG
	308	printk(KERN_DEBUG "BA request denied - HW unavailable for"
	309	" tid %d\n", tid);
	310	#endif /* CONFIG_MAC80211_HT_DEBUG */
	311	*state = HT_AGG_STATE_IDLE;
	312	goto err_unlock_queue;
	313	}
	314
	315	/* Will put all the packets in the new SW queue */
	316	if (hw->ampdu_queues)
	317	ieee80211_requeue(local, ieee802_1d_to_ac[tid]);
	318	spin_unlock_bh(&sta->lock);
	319
	320	/* send an addBA request */
	321	sta->ampdu_mlme.dialog_token_allocator++;
	322	sta->ampdu_mlme.tid_tx[tid]->dialog_token =
	323	sta->ampdu_mlme.dialog_token_allocator;
	324	sta->ampdu_mlme.tid_tx[tid]->ssn = start_seq_num;
	325
	326
	327	ieee80211_send_addba_request(sta->sdata, ra, tid,
	328	sta->ampdu_mlme.tid_tx[tid]->dialog_token,
	329	sta->ampdu_mlme.tid_tx[tid]->ssn,
	330	0x40, 5000);
	331	/* activate the timer for the recipient's addBA response */
	332	sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.expires =
	333	jiffies + ADDBA_RESP_INTERVAL;
	334	add_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
	335	#ifdef CONFIG_MAC80211_HT_DEBUG
	336	printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
	337	#endif
	338	goto exit;
	339
	340	err_unlock_queue:
	341	kfree(sta->ampdu_mlme.tid_tx[tid]);
	342	sta->ampdu_mlme.tid_tx[tid] = NULL;
	343	ret = -EBUSY;
	344	err_unlock_sta:
	345	spin_unlock_bh(&sta->lock);
	346	exit:
	347	rcu_read_unlock();
	348	return ret;
	349	}
	350	EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
	351
	352	void ieee80211_start_tx_ba_cb(struct ieee80211_hw hw, u8 ra, u16 tid)
	353	{
	354	struct ieee80211_local *local = hw_to_local(hw);
	355	struct sta_info *sta;
	356	u8 *state;
	357
	358	if (tid >= STA_TID_NUM) {
	359	#ifdef CONFIG_MAC80211_HT_DEBUG
	360	printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
	361	tid, STA_TID_NUM);
	362	#endif
	363	return;
364	}
365
366	rcu_read_lock();
367	sta = sta_info_get(local, ra);
368	if (!sta) {
369	rcu_read_unlock();
370	#ifdef CONFIG_MAC80211_HT_DEBUG
371	printk(KERN_DEBUG "Could not find station: %pM\n", ra);
372	#endif
373	return;
374	}
375
376	state = &sta->ampdu_mlme.tid_state_tx[tid];
377	spin_lock_bh(&sta->lock);
378
379	if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
380	#ifdef CONFIG_MAC80211_HT_DEBUG
381	printk(KERN_DEBUG "addBA was not requested yet, state is %d\n",
382	*state);
383	#endif
384	spin_unlock_bh(&sta->lock);
385	rcu_read_unlock();
386	return;
387	}
388
389	WARN_ON_ONCE(*state & HT_ADDBA_DRV_READY_MSK);
390
391	*state \|= HT_ADDBA_DRV_READY_MSK;
392
393	if (*state == HT_AGG_STATE_OPERATIONAL) {
394	#ifdef CONFIG_MAC80211_HT_DEBUG
395	printk(KERN_DEBUG "Aggregation is on for tid %d \n", tid);
396	#endif
397	if (hw->ampdu_queues)
398	ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);
399	}
400	spin_unlock_bh(&sta->lock);
401	rcu_read_unlock();
402	}
403	EXPORT_SYMBOL(ieee80211_start_tx_ba_cb);
404
86ab6c5a JB	405	void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
	406	const u8 *ra, u16 tid)
	407	{
	408	struct ieee80211_local *local = hw_to_local(hw);
	409	struct ieee80211_ra_tid *ra_tid;
	410	struct sk_buff *skb = dev_alloc_skb(0);
	411
	412	if (unlikely(!skb)) {
	413	#ifdef CONFIG_MAC80211_HT_DEBUG
	414	if (net_ratelimit())
	415	printk(KERN_WARNING "%s: Not enough memory, "
	416	"dropping start BA session", skb->dev->name);
	417	#endif
	418	return;
	419	}
	420	ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
	421	memcpy(&ra_tid->ra, ra, ETH_ALEN);
	422	ra_tid->tid = tid;
	423
	424	skb->pkt_type = IEEE80211_ADDBA_MSG;
	425	skb_queue_tail(&local->skb_queue, skb);
	426	tasklet_schedule(&local->tasklet);
	427	}
	428	EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
	429
b8695a8f JB	430
	431	int ieee80211_stop_tx_ba_session(struct ieee80211_hw *hw,
	432	u8 *ra, u16 tid,
	433	enum ieee80211_back_parties initiator)
	434	{
	435	struct ieee80211_local *local = hw_to_local(hw);
	436	struct sta_info *sta;
	437	u8 *state;
	438	int ret = 0;
	439
23e6a7ea JB	440	if (WARN_ON(!local->ops->ampdu_action))
	441	return -EINVAL;
	442
b8695a8f JB	443	if (tid >= STA_TID_NUM)
	444	return -EINVAL;
	445
	446	rcu_read_lock();
	447	sta = sta_info_get(local, ra);
	448	if (!sta) {
	449	rcu_read_unlock();
	450	return -ENOENT;
	451	}
	452
	453	/* check if the TID is in aggregation */
	454	state = &sta->ampdu_mlme.tid_state_tx[tid];
	455	spin_lock_bh(&sta->lock);
	456
	457	if (*state != HT_AGG_STATE_OPERATIONAL) {
	458	ret = -ENOENT;
23e6a7ea	459	goto unlock;
b8695a8f JB	460	}
	461
	462	#ifdef CONFIG_MAC80211_HT_DEBUG
	463	printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
	464	ra, tid);
	465	#endif /* CONFIG_MAC80211_HT_DEBUG */
	466
23e6a7ea	467	ret = __ieee80211_stop_tx_ba_session(local, sta, tid, initiator);
b8695a8f	468
23e6a7ea	469	unlock:
b8695a8f	470	spin_unlock_bh(&sta->lock);
23e6a7ea	471
b8695a8f	472	rcu_read_unlock();
23e6a7ea	473
b8695a8f JB	474	return ret;
	475	}
	476	EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
	477
	478	void ieee80211_stop_tx_ba_cb(struct ieee80211_hw hw, u8 ra, u8 tid)
	479	{
	480	struct ieee80211_local *local = hw_to_local(hw);
	481	struct sta_info *sta;
	482	u8 *state;
	483	int agg_queue;
	484
	485	if (tid >= STA_TID_NUM) {
	486	#ifdef CONFIG_MAC80211_HT_DEBUG
	487	printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
	488	tid, STA_TID_NUM);
	489	#endif
	490	return;
	491	}
	492
	493	#ifdef CONFIG_MAC80211_HT_DEBUG
	494	printk(KERN_DEBUG "Stopping Tx BA session for %pM tid %d\n",
	495	ra, tid);
	496	#endif /* CONFIG_MAC80211_HT_DEBUG */
	497
	498	rcu_read_lock();
	499	sta = sta_info_get(local, ra);
	500	if (!sta) {
	501	#ifdef CONFIG_MAC80211_HT_DEBUG
	502	printk(KERN_DEBUG "Could not find station: %pM\n", ra);
	503	#endif
	504	rcu_read_unlock();
	505	return;
	506	}
	507	state = &sta->ampdu_mlme.tid_state_tx[tid];
	508
	509	/* NOTE: no need to use sta->lock in this state check, as
	510	* ieee80211_stop_tx_ba_session will let only one stop call to
	511	* pass through per sta/tid
	512	*/
	513	if ((*state & HT_AGG_STATE_REQ_STOP_BA_MSK) == 0) {
	514	#ifdef CONFIG_MAC80211_HT_DEBUG
	515	printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
	516	#endif
	517	rcu_read_unlock();
	518	return;
	519	}
	520
	521	if (*state & HT_AGG_STATE_INITIATOR_MSK)
	522	ieee80211_send_delba(sta->sdata, ra, tid,
	523	WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
	524
	525	if (hw->ampdu_queues) {
	526	agg_queue = sta->tid_to_tx_q[tid];
	527	ieee80211_ht_agg_queue_remove(local, sta, tid, 1);
	528
	529	/* We just requeued the all the frames that were in the
	530	* removed queue, and since we might miss a softirq we do
	531	* netif_schedule_queue. ieee80211_wake_queue is not used
	532	* here as this queue is not necessarily stopped
	533	*/
	534	netif_schedule_queue(netdev_get_tx_queue(local->mdev,
	535	agg_queue));
	536	}
	537	spin_lock_bh(&sta->lock);
538	*state = HT_AGG_STATE_IDLE;
539	sta->ampdu_mlme.addba_req_num[tid] = 0;
540	kfree(sta->ampdu_mlme.tid_tx[tid]);
541	sta->ampdu_mlme.tid_tx[tid] = NULL;
542	spin_unlock_bh(&sta->lock);
543
544	rcu_read_unlock();
545	}
546	EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb);
547
b8695a8f JB	548	void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
	549	const u8 *ra, u16 tid)
	550	{
	551	struct ieee80211_local *local = hw_to_local(hw);
	552	struct ieee80211_ra_tid *ra_tid;
	553	struct sk_buff *skb = dev_alloc_skb(0);
	554
	555	if (unlikely(!skb)) {
	556	#ifdef CONFIG_MAC80211_HT_DEBUG
	557	if (net_ratelimit())
	558	printk(KERN_WARNING "%s: Not enough memory, "
	559	"dropping stop BA session", skb->dev->name);
	560	#endif
	561	return;
	562	}
	563	ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
	564	memcpy(&ra_tid->ra, ra, ETH_ALEN);
	565	ra_tid->tid = tid;
	566
	567	skb->pkt_type = IEEE80211_DELBA_MSG;
	568	skb_queue_tail(&local->skb_queue, skb);
	569	tasklet_schedule(&local->tasklet);
	570	}
	571	EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
	572
86ab6c5a	573
b8695a8f JB	574	void ieee80211_process_addba_resp(struct ieee80211_local *local,
	575	struct sta_info *sta,
	576	struct ieee80211_mgmt *mgmt,
	577	size_t len)
	578	{
	579	struct ieee80211_hw *hw = &local->hw;
	580	u16 capab;
	581	u16 tid, start_seq_num;
	582	u8 *state;
	583
	584	capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
	585	tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
	586
	587	state = &sta->ampdu_mlme.tid_state_tx[tid];
	588
	589	spin_lock_bh(&sta->lock);
	590
	591	if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
	592	spin_unlock_bh(&sta->lock);
	593	return;
	594	}
	595
	596	if (mgmt->u.action.u.addba_resp.dialog_token !=
	597	sta->ampdu_mlme.tid_tx[tid]->dialog_token) {
	598	spin_unlock_bh(&sta->lock);
	599	#ifdef CONFIG_MAC80211_HT_DEBUG
	600	printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
	601	#endif /* CONFIG_MAC80211_HT_DEBUG */
	602	return;
	603	}
	604
	605	del_timer_sync(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
	606	#ifdef CONFIG_MAC80211_HT_DEBUG
	607	printk(KERN_DEBUG "switched off addBA timer for tid %d \n", tid);
	608	#endif /* CONFIG_MAC80211_HT_DEBUG */
	609	if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
	610	== WLAN_STATUS_SUCCESS) {
	611	*state \|= HT_ADDBA_RECEIVED_MSK;
	612	sta->ampdu_mlme.addba_req_num[tid] = 0;
	613
	614	if (*state == HT_AGG_STATE_OPERATIONAL &&
	615	local->hw.ampdu_queues)
	616	ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);
	617
	618	if (local->ops->ampdu_action) {
	619	(void)local->ops->ampdu_action(hw,
	620	IEEE80211_AMPDU_TX_RESUME,
	621	&sta->sta, tid, &start_seq_num);
	622	}
	623	#ifdef CONFIG_MAC80211_HT_DEBUG
	624	printk(KERN_DEBUG "Resuming TX aggregation for tid %d\n", tid);
	625	#endif /* CONFIG_MAC80211_HT_DEBUG */
	626	spin_unlock_bh(&sta->lock);
	627	} else {
	628	sta->ampdu_mlme.addba_req_num[tid]++;
23e6a7ea JB	629	__ieee80211_stop_tx_ba_session(local, sta, tid,
23e6a7ea JB	630	WLAN_BACK_INITIATOR);
b8695a8f	631	spin_unlock_bh(&sta->lock);
b8695a8f JB	632	}
b8695a8f JB	633	}