[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 sta_info *sta, u16 tid,
					   enum ieee80211_back_parties initiator)
{
	struct ieee80211_local *local = sta->local;
	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]);
	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(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 sta_info *sta, u16 tid,
				   enum ieee80211_back_parties initiator)
{
	u8 *state;
	int ret;

	/* 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",
	       sta->sta.addr, tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */

	ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator);

 unlock:
	spin_unlock_bh(&sta->lock);
	return ret;
}

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;
	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;
	}

	ret = __ieee80211_stop_tx_ba_session(sta, tid, initiator);
	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 */
	} else {
		sta->ampdu_mlme.addba_req_num[tid]++;
		___ieee80211_stop_tx_ba_session(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
849b7967 JB	126	static int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
849b7967 JB	127	enum ieee80211_back_parties initiator)
23e6a7ea	128	{
849b7967	129	struct ieee80211_local *local = sta->local;
23e6a7ea JB	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]);
b8695a8f JB	168	u8 *state;
b8695a8f JB	169
b8695a8f	170	state = &sta->ampdu_mlme.tid_state_tx[tid];
23e6a7ea	171
b8695a8f JB	172	/* check if the TID waits for addBA response */
	173	spin_lock_bh(&sta->lock);
	174	if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
	175	spin_unlock_bh(&sta->lock);
	176	*state = HT_AGG_STATE_IDLE;
	177	#ifdef CONFIG_MAC80211_HT_DEBUG
	178	printk(KERN_DEBUG "timer expired on tid %d but we are not "
	179	"expecting addBA response there", tid);
	180	#endif
23e6a7ea	181	return;
b8695a8f JB	182	}
	183
	184	#ifdef CONFIG_MAC80211_HT_DEBUG
	185	printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
	186	#endif
	187
849b7967	188	___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR);
b8695a8f	189	spin_unlock_bh(&sta->lock);
b8695a8f JB	190	}
	191
	192	int ieee80211_start_tx_ba_session(struct ieee80211_hw hw, u8 ra, u16 tid)
	193	{
	194	struct ieee80211_local *local = hw_to_local(hw);
	195	struct sta_info *sta;
	196	struct ieee80211_sub_if_data *sdata;
	197	u16 start_seq_num;
	198	u8 *state;
	199	int ret = 0;
	200
23e6a7ea JB	201	if (WARN_ON(!local->ops->ampdu_action))
	202	return -EINVAL;
	203
b8695a8f JB	204	if ((tid >= STA_TID_NUM) \|\| !(hw->flags & IEEE80211_HW_AMPDU_AGGREGATION))
	205	return -EINVAL;
	206
	207	#ifdef CONFIG_MAC80211_HT_DEBUG
	208	printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
	209	ra, tid);
	210	#endif /* CONFIG_MAC80211_HT_DEBUG */
	211
	212	rcu_read_lock();
	213
	214	sta = sta_info_get(local, ra);
	215	if (!sta) {
	216	#ifdef CONFIG_MAC80211_HT_DEBUG
	217	printk(KERN_DEBUG "Could not find the station\n");
	218	#endif
	219	ret = -ENOENT;
	220	goto exit;
	221	}
	222
8abd3f9b JB	223	/*
	224	* The aggregation code is not prepared to handle
	225	* anything but STA/AP due to the BSSID handling.
	226	* IBSS could work in the code but isn't supported
	227	* by drivers or the standard.
	228	*/
	229	if (sta->sdata->vif.type != NL80211_IFTYPE_STATION &&
	230	sta->sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
	231	sta->sdata->vif.type != NL80211_IFTYPE_AP) {
	232	ret = -EINVAL;
	233	goto exit;
	234	}
	235
b8695a8f JB	236	spin_lock_bh(&sta->lock);
	237
	238	/* we have tried too many times, receiver does not want A-MPDU */
	239	if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
	240	ret = -EBUSY;
	241	goto err_unlock_sta;
	242	}
	243
	244	state = &sta->ampdu_mlme.tid_state_tx[tid];
	245	/* check if the TID is not in aggregation flow already */
	246	if (*state != HT_AGG_STATE_IDLE) {
	247	#ifdef CONFIG_MAC80211_HT_DEBUG
	248	printk(KERN_DEBUG "BA request denied - session is not "
	249	"idle on tid %u\n", tid);
	250	#endif /* CONFIG_MAC80211_HT_DEBUG */
	251	ret = -EAGAIN;
	252	goto err_unlock_sta;
	253	}
	254
	255	/* prepare A-MPDU MLME for Tx aggregation */
	256	sta->ampdu_mlme.tid_tx[tid] =
	257	kmalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
	258	if (!sta->ampdu_mlme.tid_tx[tid]) {
	259	#ifdef CONFIG_MAC80211_HT_DEBUG
	260	if (net_ratelimit())
	261	printk(KERN_ERR "allocate tx mlme to tid %d failed\n",
	262	tid);
	263	#endif
	264	ret = -ENOMEM;
	265	goto err_unlock_sta;
	266	}
	267	/* Tx timer */
	268	sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.function =
	269	sta_addba_resp_timer_expired;
	270	sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.data =
	271	(unsigned long)&sta->timer_to_tid[tid];
	272	init_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
	273
	274	if (hw->ampdu_queues) {
	275	/* create a new queue for this aggregation */
	276	ret = ieee80211_ht_agg_queue_add(local, sta, tid);
	277
	278	/* case no queue is available to aggregation
	279	* don't switch to aggregation */
	280	if (ret) {
	281	#ifdef CONFIG_MAC80211_HT_DEBUG
	282	printk(KERN_DEBUG "BA request denied - "
	283	"queue unavailable for tid %d\n", tid);
	284	#endif /* CONFIG_MAC80211_HT_DEBUG */
	285	goto err_unlock_queue;
	286	}
	287	}
	288	sdata = sta->sdata;
	289
	290	/* Ok, the Addba frame hasn't been sent yet, but if the driver calls the
	291	* call back right away, it must see that the flow has begun */
	292	*state \|= HT_ADDBA_REQUESTED_MSK;
	293
	294	/* This is slightly racy because the queue isn't stopped */
	295	start_seq_num = sta->tid_seq[tid];
	296
23e6a7ea JB	297	ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_TX_START,
23e6a7ea JB	298	&sta->sta, tid, &start_seq_num);
b8695a8f JB	299
	300	if (ret) {
	301	/* No need to requeue the packets in the agg queue, since we
	302	* held the tx lock: no packet could be enqueued to the newly
	303	* allocated queue */
	304	if (hw->ampdu_queues)
	305	ieee80211_ht_agg_queue_remove(local, sta, tid, 0);
	306	#ifdef CONFIG_MAC80211_HT_DEBUG
	307	printk(KERN_DEBUG "BA request denied - HW unavailable for"
	308	" tid %d\n", tid);
	309	#endif /* CONFIG_MAC80211_HT_DEBUG */
	310	*state = HT_AGG_STATE_IDLE;
	311	goto err_unlock_queue;
	312	}
	313
	314	/* Will put all the packets in the new SW queue */
	315	if (hw->ampdu_queues)
	316	ieee80211_requeue(local, ieee802_1d_to_ac[tid]);
	317	spin_unlock_bh(&sta->lock);
	318
	319	/* send an addBA request */
	320	sta->ampdu_mlme.dialog_token_allocator++;
	321	sta->ampdu_mlme.tid_tx[tid]->dialog_token =
	322	sta->ampdu_mlme.dialog_token_allocator;
	323	sta->ampdu_mlme.tid_tx[tid]->ssn = start_seq_num;
	324
	325
	326	ieee80211_send_addba_request(sta->sdata, ra, tid,
	327	sta->ampdu_mlme.tid_tx[tid]->dialog_token,
	328	sta->ampdu_mlme.tid_tx[tid]->ssn,
	329	0x40, 5000);
	330	/* activate the timer for the recipient's addBA response */
	331	sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.expires =
	332	jiffies + ADDBA_RESP_INTERVAL;
	333	add_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
	334	#ifdef CONFIG_MAC80211_HT_DEBUG
	335	printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
	336	#endif
	337	goto exit;
	338
	339	err_unlock_queue:
	340	kfree(sta->ampdu_mlme.tid_tx[tid]);
	341	sta->ampdu_mlme.tid_tx[tid] = NULL;
	342	ret = -EBUSY;
	343	err_unlock_sta:
	344	spin_unlock_bh(&sta->lock);
	345	exit:
	346	rcu_read_unlock();
	347	return ret;
	348	}
	349	EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
	350
	351	void ieee80211_start_tx_ba_cb(struct ieee80211_hw hw, u8 ra, u16 tid)
	352	{
	353	struct ieee80211_local *local = hw_to_local(hw);
	354	struct sta_info *sta;
	355	u8 *state;
	356
	357	if (tid >= STA_TID_NUM) {
	358	#ifdef CONFIG_MAC80211_HT_DEBUG
	359	printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
	360	tid, STA_TID_NUM);
	361	#endif
	362	return;
363	}
364
365	rcu_read_lock();
366	sta = sta_info_get(local, ra);
367	if (!sta) {
368	rcu_read_unlock();
369	#ifdef CONFIG_MAC80211_HT_DEBUG
370	printk(KERN_DEBUG "Could not find station: %pM\n", ra);
371	#endif
372	return;
373	}
374
375	state = &sta->ampdu_mlme.tid_state_tx[tid];
376	spin_lock_bh(&sta->lock);
377
378	if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
379	#ifdef CONFIG_MAC80211_HT_DEBUG
380	printk(KERN_DEBUG "addBA was not requested yet, state is %d\n",
381	*state);
382	#endif
383	spin_unlock_bh(&sta->lock);
384	rcu_read_unlock();
385	return;
386	}
387
388	WARN_ON_ONCE(*state & HT_ADDBA_DRV_READY_MSK);
389
390	*state \|= HT_ADDBA_DRV_READY_MSK;
391
392	if (*state == HT_AGG_STATE_OPERATIONAL) {
393	#ifdef CONFIG_MAC80211_HT_DEBUG
394	printk(KERN_DEBUG "Aggregation is on for tid %d \n", tid);
395	#endif
396	if (hw->ampdu_queues)
397	ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);
398	}
399	spin_unlock_bh(&sta->lock);
400	rcu_read_unlock();
401	}
402	EXPORT_SYMBOL(ieee80211_start_tx_ba_cb);
403
86ab6c5a JB	404	void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
	405	const u8 *ra, u16 tid)
	406	{
	407	struct ieee80211_local *local = hw_to_local(hw);
	408	struct ieee80211_ra_tid *ra_tid;
	409	struct sk_buff *skb = dev_alloc_skb(0);
	410
	411	if (unlikely(!skb)) {
	412	#ifdef CONFIG_MAC80211_HT_DEBUG
	413	if (net_ratelimit())
	414	printk(KERN_WARNING "%s: Not enough memory, "
	415	"dropping start BA session", skb->dev->name);
	416	#endif
	417	return;
	418	}
	419	ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
	420	memcpy(&ra_tid->ra, ra, ETH_ALEN);
	421	ra_tid->tid = tid;
	422
	423	skb->pkt_type = IEEE80211_ADDBA_MSG;
	424	skb_queue_tail(&local->skb_queue, skb);
	425	tasklet_schedule(&local->tasklet);
	426	}
	427	EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
	428
849b7967 JB	429	int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
	430	enum ieee80211_back_parties initiator)
	431	{
	432	u8 *state;
	433	int ret;
	434
	435	/* check if the TID is in aggregation */
	436	state = &sta->ampdu_mlme.tid_state_tx[tid];
	437	spin_lock_bh(&sta->lock);
	438
	439	if (*state != HT_AGG_STATE_OPERATIONAL) {
	440	ret = -ENOENT;
	441	goto unlock;
	442	}
	443
	444	#ifdef CONFIG_MAC80211_HT_DEBUG
	445	printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
	446	sta->sta.addr, tid);
	447	#endif /* CONFIG_MAC80211_HT_DEBUG */
	448
	449	ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator);
	450
	451	unlock:
	452	spin_unlock_bh(&sta->lock);
	453	return ret;
	454	}
b8695a8f JB	455
	456	int ieee80211_stop_tx_ba_session(struct ieee80211_hw *hw,
	457	u8 *ra, u16 tid,
	458	enum ieee80211_back_parties initiator)
	459	{
	460	struct ieee80211_local *local = hw_to_local(hw);
	461	struct sta_info *sta;
b8695a8f JB	462	int ret = 0;
b8695a8f JB	463
23e6a7ea JB	464	if (WARN_ON(!local->ops->ampdu_action))
	465	return -EINVAL;
	466
b8695a8f JB	467	if (tid >= STA_TID_NUM)
	468	return -EINVAL;
	469
	470	rcu_read_lock();
	471	sta = sta_info_get(local, ra);
	472	if (!sta) {
	473	rcu_read_unlock();
	474	return -ENOENT;
	475	}
	476
849b7967	477	ret = __ieee80211_stop_tx_ba_session(sta, tid, initiator);
b8695a8f JB	478	rcu_read_unlock();
	479	return ret;
	480	}
	481	EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
	482
	483	void ieee80211_stop_tx_ba_cb(struct ieee80211_hw hw, u8 ra, u8 tid)
	484	{
	485	struct ieee80211_local *local = hw_to_local(hw);
	486	struct sta_info *sta;
	487	u8 *state;
	488	int agg_queue;
	489
	490	if (tid >= STA_TID_NUM) {
	491	#ifdef CONFIG_MAC80211_HT_DEBUG
	492	printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
	493	tid, STA_TID_NUM);
	494	#endif
	495	return;
	496	}
	497
	498	#ifdef CONFIG_MAC80211_HT_DEBUG
	499	printk(KERN_DEBUG "Stopping Tx BA session for %pM tid %d\n",
	500	ra, tid);
	501	#endif /* CONFIG_MAC80211_HT_DEBUG */
	502
	503	rcu_read_lock();
	504	sta = sta_info_get(local, ra);
	505	if (!sta) {
	506	#ifdef CONFIG_MAC80211_HT_DEBUG
	507	printk(KERN_DEBUG "Could not find station: %pM\n", ra);
	508	#endif
	509	rcu_read_unlock();
	510	return;
	511	}
	512	state = &sta->ampdu_mlme.tid_state_tx[tid];
	513
	514	/* NOTE: no need to use sta->lock in this state check, as
	515	* ieee80211_stop_tx_ba_session will let only one stop call to
	516	* pass through per sta/tid
	517	*/
	518	if ((*state & HT_AGG_STATE_REQ_STOP_BA_MSK) == 0) {
	519	#ifdef CONFIG_MAC80211_HT_DEBUG
	520	printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
	521	#endif
	522	rcu_read_unlock();
	523	return;
	524	}
	525
	526	if (*state & HT_AGG_STATE_INITIATOR_MSK)
	527	ieee80211_send_delba(sta->sdata, ra, tid,
	528	WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
	529
	530	if (hw->ampdu_queues) {
	531	agg_queue = sta->tid_to_tx_q[tid];
	532	ieee80211_ht_agg_queue_remove(local, sta, tid, 1);
	533
	534	/* We just requeued the all the frames that were in the
	535	* removed queue, and since we might miss a softirq we do
	536	* netif_schedule_queue. ieee80211_wake_queue is not used
	537	* here as this queue is not necessarily stopped
	538	*/
	539	netif_schedule_queue(netdev_get_tx_queue(local->mdev,
	540	agg_queue));
	541	}
542	spin_lock_bh(&sta->lock);
543	*state = HT_AGG_STATE_IDLE;
544	sta->ampdu_mlme.addba_req_num[tid] = 0;
545	kfree(sta->ampdu_mlme.tid_tx[tid]);
546	sta->ampdu_mlme.tid_tx[tid] = NULL;
547	spin_unlock_bh(&sta->lock);
548
549	rcu_read_unlock();
550	}
551	EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb);
552
b8695a8f JB	553	void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
	554	const u8 *ra, u16 tid)
	555	{
	556	struct ieee80211_local *local = hw_to_local(hw);
	557	struct ieee80211_ra_tid *ra_tid;
	558	struct sk_buff *skb = dev_alloc_skb(0);
	559
	560	if (unlikely(!skb)) {
	561	#ifdef CONFIG_MAC80211_HT_DEBUG
	562	if (net_ratelimit())
	563	printk(KERN_WARNING "%s: Not enough memory, "
	564	"dropping stop BA session", skb->dev->name);
	565	#endif
	566	return;
	567	}
	568	ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
	569	memcpy(&ra_tid->ra, ra, ETH_ALEN);
	570	ra_tid->tid = tid;
	571
	572	skb->pkt_type = IEEE80211_DELBA_MSG;
	573	skb_queue_tail(&local->skb_queue, skb);
	574	tasklet_schedule(&local->tasklet);
	575	}
	576	EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
	577
86ab6c5a	578
b8695a8f JB	579	void ieee80211_process_addba_resp(struct ieee80211_local *local,
	580	struct sta_info *sta,
	581	struct ieee80211_mgmt *mgmt,
	582	size_t len)
	583	{
	584	struct ieee80211_hw *hw = &local->hw;
	585	u16 capab;
	586	u16 tid, start_seq_num;
	587	u8 *state;
	588
	589	capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
	590	tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
	591
	592	state = &sta->ampdu_mlme.tid_state_tx[tid];
	593
	594	spin_lock_bh(&sta->lock);
	595
	596	if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
	597	spin_unlock_bh(&sta->lock);
	598	return;
	599	}
	600
	601	if (mgmt->u.action.u.addba_resp.dialog_token !=
	602	sta->ampdu_mlme.tid_tx[tid]->dialog_token) {
	603	spin_unlock_bh(&sta->lock);
	604	#ifdef CONFIG_MAC80211_HT_DEBUG
	605	printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
	606	#endif /* CONFIG_MAC80211_HT_DEBUG */
	607	return;
	608	}
	609
	610	del_timer_sync(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
	611	#ifdef CONFIG_MAC80211_HT_DEBUG
	612	printk(KERN_DEBUG "switched off addBA timer for tid %d \n", tid);
	613	#endif /* CONFIG_MAC80211_HT_DEBUG */
	614	if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
	615	== WLAN_STATUS_SUCCESS) {
	616	*state \|= HT_ADDBA_RECEIVED_MSK;
	617	sta->ampdu_mlme.addba_req_num[tid] = 0;
	618
	619	if (*state == HT_AGG_STATE_OPERATIONAL &&
	620	local->hw.ampdu_queues)
	621	ieee80211_wake_queue(hw, sta->tid_to_tx_q[tid]);
	622
	623	if (local->ops->ampdu_action) {
	624	(void)local->ops->ampdu_action(hw,
	625	IEEE80211_AMPDU_TX_RESUME,
	626	&sta->sta, tid, &start_seq_num);
	627	}
	628	#ifdef CONFIG_MAC80211_HT_DEBUG
	629	printk(KERN_DEBUG "Resuming TX aggregation for tid %d\n", tid);
	630	#endif /* CONFIG_MAC80211_HT_DEBUG */
b8695a8f JB	631	} else {
b8695a8f JB	632	sta->ampdu_mlme.addba_req_num[tid]++;
849b7967	633	___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR);
b8695a8f	634	}
849b7967	635	spin_unlock_bh(&sta->lock);
b8695a8f	636	}