[net-next-2.6.git] / net / mac80211 / agg-rx.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 2007-2008, 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 <linux/slab.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"

static void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
					    u16 initiator, u16 reason,
					    bool from_timer)
{
	struct ieee80211_local *local = sta->local;
	struct tid_ampdu_rx *tid_rx;
	int i;

	spin_lock_bh(&sta->lock);

	/* check if TID is in operational state */
	if (!sta->ampdu_mlme.tid_active_rx[tid]) {
		spin_unlock_bh(&sta->lock);
		return;
	}

	sta->ampdu_mlme.tid_active_rx[tid] = false;

	tid_rx = sta->ampdu_mlme.tid_rx[tid];

#ifdef CONFIG_MAC80211_HT_DEBUG
	printk(KERN_DEBUG "Rx BA session stop requested for %pM tid %u\n",
	       sta->sta.addr, tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */

	if (drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_STOP,
			     &sta->sta, tid, NULL))
		printk(KERN_DEBUG "HW problem - can not stop rx "
				"aggregation for tid %d\n", tid);

	/* check if this is a self generated aggregation halt */
	if (initiator == WLAN_BACK_RECIPIENT)
		ieee80211_send_delba(sta->sdata, sta->sta.addr,
				     tid, 0, reason);

	/* free the reordering buffer */
	for (i = 0; i < tid_rx->buf_size; i++) {
		if (tid_rx->reorder_buf[i]) {
			/* release the reordered frames */
			dev_kfree_skb(tid_rx->reorder_buf[i]);
			tid_rx->stored_mpdu_num--;
			tid_rx->reorder_buf[i] = NULL;
		}
	}

	/* free resources */
	kfree(tid_rx->reorder_buf);
	kfree(tid_rx->reorder_time);
	sta->ampdu_mlme.tid_rx[tid] = NULL;

	spin_unlock_bh(&sta->lock);

	if (!from_timer)
		del_timer_sync(&tid_rx->session_timer);
	kfree(tid_rx);
}

void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
				    u16 initiator, u16 reason)
{
	___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, false);
}

/*
 * After accepting the AddBA Request we activated a timer,
 * resetting it after each frame that arrives from the originator.
 */
static void sta_rx_agg_session_timer_expired(unsigned long data)
{
	/* not an elegant detour, but there is no choice as the timer passes
	 * only one argument, and various sta_info are needed here, so init
	 * flow in sta_info_create gives the TID as data, while the timer_to_id
	 * array gives the sta through container_of */
	u8 *ptid = (u8 *)data;
	u8 *timer_to_id = ptid - *ptid;
	struct sta_info *sta = container_of(timer_to_id, struct sta_info,
					 timer_to_tid[0]);

#ifdef CONFIG_MAC80211_HT_DEBUG
	printk(KERN_DEBUG "rx session timer expired on tid %d\n", (u16)*ptid);
#endif
	___ieee80211_stop_rx_ba_session(sta, *ptid, WLAN_BACK_RECIPIENT,
					WLAN_REASON_QSTA_TIMEOUT, true);
}

static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data *sdata, u8 *da, u16 tid,
				      u8 dialog_token, u16 status, u16 policy,
				      u16 buf_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) {
		printk(KERN_DEBUG "%s: failed to allocate buffer "
		       "for addba resp frame\n", sdata->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->vif.addr, ETH_ALEN);
	if (sdata->vif.type == NL80211_IFTYPE_AP ||
	    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
		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);

	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
					  IEEE80211_STYPE_ACTION);

	skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
	mgmt->u.action.category = WLAN_CATEGORY_BACK;
	mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
	mgmt->u.action.u.addba_resp.dialog_token = dialog_token;

	capab = (u16)(policy << 1);	/* bit 1 aggregation policy */
	capab |= (u16)(tid << 2); 	/* bit 5:2 TID number */
	capab |= (u16)(buf_size << 6);	/* bit 15:6 max size of aggregation */

	mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
	mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
	mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);

	ieee80211_tx_skb(sdata, skb);
}

void ieee80211_process_addba_request(struct ieee80211_local *local,
				     struct sta_info *sta,
				     struct ieee80211_mgmt *mgmt,
				     size_t len)
{
	struct ieee80211_hw *hw = &local->hw;
	struct ieee80211_conf *conf = &hw->conf;
	struct tid_ampdu_rx *tid_agg_rx;
	u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num, status;
	u8 dialog_token;
	int ret = -EOPNOTSUPP;

	/* extract session parameters from addba request frame */
	dialog_token = mgmt->u.action.u.addba_req.dialog_token;
	timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
	start_seq_num =
		le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;

	capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
	ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
	tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
	buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;

	status = WLAN_STATUS_REQUEST_DECLINED;

	if (test_sta_flags(sta, WLAN_STA_BLOCK_BA)) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		printk(KERN_DEBUG "Suspend in progress. "
		       "Denying ADDBA request\n");
#endif
		goto end_no_lock;
	}

	/* sanity check for incoming parameters:
	 * check if configuration can support the BA policy
	 * and if buffer size does not exceeds max value */
	/* XXX: check own ht delayed BA capability?? */
	if (((ba_policy != 1) &&
	     (!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) ||
	    (buf_size > IEEE80211_MAX_AMPDU_BUF)) {
		status = WLAN_STATUS_INVALID_QOS_PARAM;
#ifdef CONFIG_MAC80211_HT_DEBUG
		if (net_ratelimit())
			printk(KERN_DEBUG "AddBA Req with bad params from "
				"%pM on tid %u. policy %d, buffer size %d\n",
				mgmt->sa, tid, ba_policy,
				buf_size);
#endif /* CONFIG_MAC80211_HT_DEBUG */
		goto end_no_lock;
	}
	/* determine default buffer size */
	if (buf_size == 0) {
		struct ieee80211_supported_band *sband;

		sband = local->hw.wiphy->bands[conf->channel->band];
		buf_size = IEEE80211_MIN_AMPDU_BUF;
		buf_size = buf_size << sband->ht_cap.ampdu_factor;
	}


	/* examine state machine */
	spin_lock_bh(&sta->lock);

	if (sta->ampdu_mlme.tid_active_rx[tid]) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		if (net_ratelimit())
			printk(KERN_DEBUG "unexpected AddBA Req from "
				"%pM on tid %u\n",
				mgmt->sa, tid);
#endif /* CONFIG_MAC80211_HT_DEBUG */
		goto end;
	}

	/* prepare A-MPDU MLME for Rx aggregation */
	sta->ampdu_mlme.tid_rx[tid] =
			kmalloc(sizeof(struct tid_ampdu_rx), GFP_ATOMIC);
	if (!sta->ampdu_mlme.tid_rx[tid]) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		if (net_ratelimit())
			printk(KERN_ERR "allocate rx mlme to tid %d failed\n",
					tid);
#endif
		goto end;
	}
	/* rx timer */
	sta->ampdu_mlme.tid_rx[tid]->session_timer.function =
				sta_rx_agg_session_timer_expired;
	sta->ampdu_mlme.tid_rx[tid]->session_timer.data =
				(unsigned long)&sta->timer_to_tid[tid];
	init_timer(&sta->ampdu_mlme.tid_rx[tid]->session_timer);

	tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];

	/* prepare reordering buffer */
	tid_agg_rx->reorder_buf =
		kcalloc(buf_size, sizeof(struct sk_buff *), GFP_ATOMIC);
	tid_agg_rx->reorder_time =
		kcalloc(buf_size, sizeof(unsigned long), GFP_ATOMIC);
	if (!tid_agg_rx->reorder_buf || !tid_agg_rx->reorder_time) {
#ifdef CONFIG_MAC80211_HT_DEBUG
		if (net_ratelimit())
			printk(KERN_ERR "can not allocate reordering buffer "
			       "to tid %d\n", tid);
#endif
		kfree(tid_agg_rx->reorder_buf);
		kfree(tid_agg_rx->reorder_time);
		kfree(sta->ampdu_mlme.tid_rx[tid]);
		sta->ampdu_mlme.tid_rx[tid] = NULL;
		goto end;
	}

	ret = drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_START,
			       &sta->sta, tid, &start_seq_num);
#ifdef CONFIG_MAC80211_HT_DEBUG
	printk(KERN_DEBUG "Rx A-MPDU request on tid %d result %d\n", tid, ret);
#endif /* CONFIG_MAC80211_HT_DEBUG */

	if (ret) {
		kfree(tid_agg_rx->reorder_buf);
		kfree(tid_agg_rx);
		sta->ampdu_mlme.tid_rx[tid] = NULL;
		goto end;
	}

	/* change state and send addba resp */
	sta->ampdu_mlme.tid_active_rx[tid] = true;
	tid_agg_rx->dialog_token = dialog_token;
	tid_agg_rx->ssn = start_seq_num;
	tid_agg_rx->head_seq_num = start_seq_num;
	tid_agg_rx->buf_size = buf_size;
	tid_agg_rx->timeout = timeout;
	tid_agg_rx->stored_mpdu_num = 0;
	status = WLAN_STATUS_SUCCESS;
end:
	spin_unlock_bh(&sta->lock);

end_no_lock:
	ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
				  dialog_token, status, 1, buf_size, timeout);
}
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 2007-2008, 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>
5a0e3ad6	17	#include <linux/slab.h>
b8695a8f JB	18	#include <net/mac80211.h>
b8695a8f JB	19	#include "ieee80211_i.h"
24487981	20	#include "driver-ops.h"
b8695a8f	21
2aab4c27 JB	22	static void ___ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
	23	u16 initiator, u16 reason,
	24	bool from_timer)
b8695a8f	25	{
d75636ef	26	struct ieee80211_local *local = sta->local;
098a6070	27	struct tid_ampdu_rx *tid_rx;
d75636ef	28	int i;
b8695a8f	29
b8695a8f	30	spin_lock_bh(&sta->lock);
098a6070 JB	31
	32	/* check if TID is in operational state */
	33	if (!sta->ampdu_mlme.tid_active_rx[tid]) {
b8695a8f	34	spin_unlock_bh(&sta->lock);
b8695a8f JB	35	return;
b8695a8f JB	36	}
d75636ef	37
098a6070 JB	38	sta->ampdu_mlme.tid_active_rx[tid] = false;
	39
	40	tid_rx = sta->ampdu_mlme.tid_rx[tid];
b8695a8f	41
b8695a8f JB	42	#ifdef CONFIG_MAC80211_HT_DEBUG
b8695a8f JB	43	printk(KERN_DEBUG "Rx BA session stop requested for %pM tid %u\n",
d75636ef	44	sta->sta.addr, tid);
b8695a8f JB	45	#endif /* CONFIG_MAC80211_HT_DEBUG */
b8695a8f JB	46
12375ef9	47	if (drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_STOP,
24487981	48	&sta->sta, tid, NULL))
b8695a8f JB	49	printk(KERN_DEBUG "HW problem - can not stop rx "
	50	"aggregation for tid %d\n", tid);
	51
b8695a8f	52	/* check if this is a self generated aggregation halt */
098a6070	53	if (initiator == WLAN_BACK_RECIPIENT)
d75636ef JB	54	ieee80211_send_delba(sta->sdata, sta->sta.addr,
d75636ef JB	55	tid, 0, reason);
b8695a8f JB	56
b8695a8f JB	57	/* free the reordering buffer */
098a6070 JB	58	for (i = 0; i < tid_rx->buf_size; i++) {
098a6070 JB	59	if (tid_rx->reorder_buf[i]) {
b8695a8f	60	/* release the reordered frames */
098a6070 JB	61	dev_kfree_skb(tid_rx->reorder_buf[i]);
	62	tid_rx->stored_mpdu_num--;
	63	tid_rx->reorder_buf[i] = NULL;
b8695a8f JB	64	}
b8695a8f JB	65	}
55687e38	66
b8695a8f	67	/* free resources */
098a6070 JB	68	kfree(tid_rx->reorder_buf);
	69	kfree(tid_rx->reorder_time);
	70	sta->ampdu_mlme.tid_rx[tid] = NULL;
55687e38	71
55687e38	72	spin_unlock_bh(&sta->lock);
b8695a8f	73
2aab4c27 JB	74	if (!from_timer)
2aab4c27 JB	75	del_timer_sync(&tid_rx->session_timer);
098a6070	76	kfree(tid_rx);
b8695a8f JB	77	}
b8695a8f JB	78
2aab4c27 JB	79	void __ieee80211_stop_rx_ba_session(struct sta_info *sta, u16 tid,
	80	u16 initiator, u16 reason)
	81	{
	82	___ieee80211_stop_rx_ba_session(sta, tid, initiator, reason, false);
	83	}
	84
b8695a8f JB	85	/*
	86	* After accepting the AddBA Request we activated a timer,
	87	* resetting it after each frame that arrives from the originator.
b8695a8f JB	88	*/
	89	static void sta_rx_agg_session_timer_expired(unsigned long data)
	90	{
	91	/* not an elegant detour, but there is no choice as the timer passes
	92	* only one argument, and various sta_info are needed here, so init
	93	* flow in sta_info_create gives the TID as data, while the timer_to_id
	94	* array gives the sta through container_of */
	95	u8 ptid = (u8 )data;
	96	u8 timer_to_id = ptid - ptid;
	97	struct sta_info *sta = container_of(timer_to_id, struct sta_info,
	98	timer_to_tid[0]);
	99
	100	#ifdef CONFIG_MAC80211_HT_DEBUG
	101	printk(KERN_DEBUG "rx session timer expired on tid %d\n", (u16)*ptid);
	102	#endif
2aab4c27 JB	103	___ieee80211_stop_rx_ba_session(sta, *ptid, WLAN_BACK_RECIPIENT,
2aab4c27 JB	104	WLAN_REASON_QSTA_TIMEOUT, true);
b8695a8f JB	105	}
	106
	107	static void ieee80211_send_addba_resp(struct ieee80211_sub_if_data sdata, u8 da, u16 tid,
	108	u8 dialog_token, u16 status, u16 policy,
	109	u16 buf_size, u16 timeout)
	110	{
b8695a8f JB	111	struct ieee80211_local *local = sdata->local;
	112	struct sk_buff *skb;
	113	struct ieee80211_mgmt *mgmt;
	114	u16 capab;
	115
	116	skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
	117
	118	if (!skb) {
	119	printk(KERN_DEBUG "%s: failed to allocate buffer "
47846c9b	120	"for addba resp frame\n", sdata->name);
b8695a8f JB	121	return;
	122	}
	123
	124	skb_reserve(skb, local->hw.extra_tx_headroom);
	125	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
	126	memset(mgmt, 0, 24);
	127	memcpy(mgmt->da, da, ETH_ALEN);
47846c9b	128	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
8abd3f9b JB	129	if (sdata->vif.type == NL80211_IFTYPE_AP \|\|
8abd3f9b JB	130	sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
47846c9b	131	memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
46900298 JB	132	else if (sdata->vif.type == NL80211_IFTYPE_STATION)
	133	memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
	134
b8695a8f JB	135	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT \|
	136	IEEE80211_STYPE_ACTION);
	137
	138	skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_resp));
	139	mgmt->u.action.category = WLAN_CATEGORY_BACK;
	140	mgmt->u.action.u.addba_resp.action_code = WLAN_ACTION_ADDBA_RESP;
	141	mgmt->u.action.u.addba_resp.dialog_token = dialog_token;
	142
	143	capab = (u16)(policy << 1); /* bit 1 aggregation policy */
	144	capab \|= (u16)(tid << 2); /* bit 5:2 TID number */
	145	capab \|= (u16)(buf_size << 6); /* bit 15:6 max size of aggregation */
	146
	147	mgmt->u.action.u.addba_resp.capab = cpu_to_le16(capab);
	148	mgmt->u.action.u.addba_resp.timeout = cpu_to_le16(timeout);
	149	mgmt->u.action.u.addba_resp.status = cpu_to_le16(status);
	150
62ae67be	151	ieee80211_tx_skb(sdata, skb);
b8695a8f JB	152	}
	153
	154	void ieee80211_process_addba_request(struct ieee80211_local *local,
	155	struct sta_info *sta,
	156	struct ieee80211_mgmt *mgmt,
	157	size_t len)
	158	{
	159	struct ieee80211_hw *hw = &local->hw;
	160	struct ieee80211_conf *conf = &hw->conf;
	161	struct tid_ampdu_rx *tid_agg_rx;
	162	u16 capab, tid, timeout, ba_policy, buf_size, start_seq_num, status;
	163	u8 dialog_token;
	164	int ret = -EOPNOTSUPP;
	165
	166	/* extract session parameters from addba request frame */
	167	dialog_token = mgmt->u.action.u.addba_req.dialog_token;
	168	timeout = le16_to_cpu(mgmt->u.action.u.addba_req.timeout);
	169	start_seq_num =
	170	le16_to_cpu(mgmt->u.action.u.addba_req.start_seq_num) >> 4;
	171
	172	capab = le16_to_cpu(mgmt->u.action.u.addba_req.capab);
	173	ba_policy = (capab & IEEE80211_ADDBA_PARAM_POLICY_MASK) >> 1;
	174	tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
	175	buf_size = (capab & IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK) >> 6;
	176
	177	status = WLAN_STATUS_REQUEST_DECLINED;
	178
618f356b	179	if (test_sta_flags(sta, WLAN_STA_BLOCK_BA)) {
722f069a S	180	#ifdef CONFIG_MAC80211_HT_DEBUG
	181	printk(KERN_DEBUG "Suspend in progress. "
	182	"Denying ADDBA request\n");
	183	#endif
	184	goto end_no_lock;
	185	}
	186
b8695a8f JB	187	/* sanity check for incoming parameters:
	188	* check if configuration can support the BA policy
	189	* and if buffer size does not exceeds max value */
	190	/* XXX: check own ht delayed BA capability?? */
f64f9e71 JP	191	if (((ba_policy != 1) &&
	192	(!(sta->sta.ht_cap.cap & IEEE80211_HT_CAP_DELAY_BA))) \|\|
	193	(buf_size > IEEE80211_MAX_AMPDU_BUF)) {
b8695a8f JB	194	status = WLAN_STATUS_INVALID_QOS_PARAM;
	195	#ifdef CONFIG_MAC80211_HT_DEBUG
	196	if (net_ratelimit())
	197	printk(KERN_DEBUG "AddBA Req with bad params from "
	198	"%pM on tid %u. policy %d, buffer size %d\n",
	199	mgmt->sa, tid, ba_policy,
	200	buf_size);
	201	#endif /* CONFIG_MAC80211_HT_DEBUG */
	202	goto end_no_lock;
	203	}
	204	/* determine default buffer size */
	205	if (buf_size == 0) {
	206	struct ieee80211_supported_band *sband;
	207
	208	sband = local->hw.wiphy->bands[conf->channel->band];
	209	buf_size = IEEE80211_MIN_AMPDU_BUF;
	210	buf_size = buf_size << sband->ht_cap.ampdu_factor;
	211	}
	212
	213
	214	/* examine state machine */
	215	spin_lock_bh(&sta->lock);
	216
098a6070	217	if (sta->ampdu_mlme.tid_active_rx[tid]) {
b8695a8f JB	218	#ifdef CONFIG_MAC80211_HT_DEBUG
	219	if (net_ratelimit())
	220	printk(KERN_DEBUG "unexpected AddBA Req from "
	221	"%pM on tid %u\n",
	222	mgmt->sa, tid);
	223	#endif /* CONFIG_MAC80211_HT_DEBUG */
	224	goto end;
	225	}
	226
	227	/* prepare A-MPDU MLME for Rx aggregation */
	228	sta->ampdu_mlme.tid_rx[tid] =
	229	kmalloc(sizeof(struct tid_ampdu_rx), GFP_ATOMIC);
	230	if (!sta->ampdu_mlme.tid_rx[tid]) {
	231	#ifdef CONFIG_MAC80211_HT_DEBUG
	232	if (net_ratelimit())
	233	printk(KERN_ERR "allocate rx mlme to tid %d failed\n",
	234	tid);
	235	#endif
	236	goto end;
	237	}
	238	/* rx timer */
	239	sta->ampdu_mlme.tid_rx[tid]->session_timer.function =
	240	sta_rx_agg_session_timer_expired;
	241	sta->ampdu_mlme.tid_rx[tid]->session_timer.data =
	242	(unsigned long)&sta->timer_to_tid[tid];
	243	init_timer(&sta->ampdu_mlme.tid_rx[tid]->session_timer);
	244
	245	tid_agg_rx = sta->ampdu_mlme.tid_rx[tid];
	246
	247	/* prepare reordering buffer */
	248	tid_agg_rx->reorder_buf =
	249	kcalloc(buf_size, sizeof(struct sk_buff *), GFP_ATOMIC);
4d050f1d JM	250	tid_agg_rx->reorder_time =
	251	kcalloc(buf_size, sizeof(unsigned long), GFP_ATOMIC);
	252	if (!tid_agg_rx->reorder_buf \|\| !tid_agg_rx->reorder_time) {
b8695a8f JB	253	#ifdef CONFIG_MAC80211_HT_DEBUG
	254	if (net_ratelimit())
	255	printk(KERN_ERR "can not allocate reordering buffer "
	256	"to tid %d\n", tid);
	257	#endif
4d050f1d JM	258	kfree(tid_agg_rx->reorder_buf);
4d050f1d JM	259	kfree(tid_agg_rx->reorder_time);
b8695a8f	260	kfree(sta->ampdu_mlme.tid_rx[tid]);
4d050f1d	261	sta->ampdu_mlme.tid_rx[tid] = NULL;
b8695a8f JB	262	goto end;
	263	}
	264
12375ef9	265	ret = drv_ampdu_action(local, sta->sdata, IEEE80211_AMPDU_RX_START,
24487981	266	&sta->sta, tid, &start_seq_num);
b8695a8f JB	267	#ifdef CONFIG_MAC80211_HT_DEBUG
	268	printk(KERN_DEBUG "Rx A-MPDU request on tid %d result %d\n", tid, ret);
	269	#endif /* CONFIG_MAC80211_HT_DEBUG */
	270
	271	if (ret) {
	272	kfree(tid_agg_rx->reorder_buf);
	273	kfree(tid_agg_rx);
	274	sta->ampdu_mlme.tid_rx[tid] = NULL;
	275	goto end;
	276	}
	277
	278	/* change state and send addba resp */
098a6070	279	sta->ampdu_mlme.tid_active_rx[tid] = true;
b8695a8f JB	280	tid_agg_rx->dialog_token = dialog_token;
	281	tid_agg_rx->ssn = start_seq_num;
	282	tid_agg_rx->head_seq_num = start_seq_num;
	283	tid_agg_rx->buf_size = buf_size;
	284	tid_agg_rx->timeout = timeout;
	285	tid_agg_rx->stored_mpdu_num = 0;
	286	status = WLAN_STATUS_SUCCESS;
	287	end:
	288	spin_unlock_bh(&sta->lock);
	289
	290	end_no_lock:
	291	ieee80211_send_addba_resp(sta->sdata, sta->sta.addr, tid,
	292	dialog_token, status, 1, buf_size, timeout);
	293	}