/*
   * Copyright 2002-2005, Instant802 Networks, Inc.
   * Copyright 2005-2006, Devicescape Software, Inc.
   * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>

   * Copyright 2008-2010	Johannes Berg <johannes@sipsolutions.net>

   *
   * 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/export.h>

  #include <net/mac80211.h>
  #include "ieee80211_i.h"
  #include "rate.h"
  #include "mesh.h"
  #include "led.h"

  #include "wme.h"

  
  
  void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
  				 struct sk_buff *skb)
  {
  	struct ieee80211_local *local = hw_to_local(hw);
  	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  	int tmp;
  
  	skb->pkt_type = IEEE80211_TX_STATUS_MSG;
  	skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ?
  		       &local->skb_queue : &local->skb_queue_unreliable, skb);
  	tmp = skb_queue_len(&local->skb_queue) +
  		skb_queue_len(&local->skb_queue_unreliable);
  	while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT &&
  	       (skb = skb_dequeue(&local->skb_queue_unreliable))) {
  		dev_kfree_skb_irq(skb);
  		tmp--;
  		I802_DEBUG_INC(local->tx_status_drop);
  	}
  	tasklet_schedule(&local->tasklet);
  }
  EXPORT_SYMBOL(ieee80211_tx_status_irqsafe);
  
  static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
  					    struct sta_info *sta,
  					    struct sk_buff *skb)
  {
  	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);

  	struct ieee80211_hdr *hdr = (void *)skb->data;
  	int ac;

  
  	/*

  	 * This skb 'survived' a round-trip through the driver, and
  	 * hopefully the driver didn't mangle it too badly. However,

  	 * we can definitely not rely on the control information

  	 * being correct. Clear it so we don't get junk there, and
  	 * indicate that it needs new processing, but must not be
  	 * modified/encrypted again.

  	 */
  	memset(&info->control, 0, sizeof(info->control));

  
  	info->control.jiffies = jiffies;
  	info->control.vif = &sta->sdata->vif;

  	info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING |
  		       IEEE80211_TX_INTFL_RETRANSMISSION;

  	info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;

  	sta->tx_filtered_count++;

  	/*
  	 * Clear more-data bit on filtered frames, it might be set
  	 * but later frames might time out so it might have to be
  	 * clear again ... It's all rather unlikely (this frame
  	 * should time out first, right?) but let's not confuse
  	 * peers unnecessarily.
  	 */
  	if (hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_MOREDATA))
  		hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_MOREDATA);

  	if (ieee80211_is_data_qos(hdr->frame_control)) {

  		u8 *p = ieee80211_get_qos_ctl(hdr);
  		int tid = *p & IEEE80211_QOS_CTL_TID_MASK;
  
  		/*
  		 * Clear EOSP if set, this could happen e.g.
  		 * if an absence period (us being a P2P GO)
  		 * shortens the SP.
  		 */
  		if (*p & IEEE80211_QOS_CTL_EOSP)
  			*p &= ~IEEE80211_QOS_CTL_EOSP;

  		ac = ieee802_1d_to_ac[tid & 7];
  	} else {
  		ac = IEEE80211_AC_BE;
  	}

  	/*
  	 * Clear the TX filter mask for this STA when sending the next
  	 * packet. If the STA went to power save mode, this will happen
  	 * when it wakes up for the next time.
  	 */

  	set_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT);

  
  	/*
  	 * This code races in the following way:
  	 *
  	 *  (1) STA sends frame indicating it will go to sleep and does so
  	 *  (2) hardware/firmware adds STA to filter list, passes frame up
  	 *  (3) hardware/firmware processes TX fifo and suppresses a frame
  	 *  (4) we get TX status before having processed the frame and
  	 *	knowing that the STA has gone to sleep.
  	 *
  	 * This is actually quite unlikely even when both those events are
  	 * processed from interrupts coming in quickly after one another or
  	 * even at the same time because we queue both TX status events and
  	 * RX frames to be processed by a tasklet and process them in the
  	 * same order that they were received or TX status last. Hence, there
  	 * is no race as long as the frame RX is processed before the next TX
  	 * status, which drivers can ensure, see below.
  	 *
  	 * Note that this can only happen if the hardware or firmware can
  	 * actually add STAs to the filter list, if this is done by the
  	 * driver in response to set_tim() (which will only reduce the race
  	 * this whole filtering tries to solve, not completely solve it)
  	 * this situation cannot happen.
  	 *
  	 * To completely solve this race drivers need to make sure that they
  	 *  (a) don't mix the irq-safe/not irq-safe TX status/RX processing
  	 *	functions and
  	 *  (b) always process RX events before TX status events if ordering
  	 *      can be unknown, for example with different interrupt status
  	 *	bits.

  	 *  (c) if PS mode transitions are manual (i.e. the flag
  	 *      %IEEE80211_HW_AP_LINK_PS is set), always process PS state
  	 *      changes before calling TX status events if ordering can be
  	 *	unknown.

  	 */

  	if (test_sta_flag(sta, WLAN_STA_PS_STA) &&

  	    skb_queue_len(&sta->tx_filtered[ac]) < STA_MAX_TX_BUFFER) {
  		skb_queue_tail(&sta->tx_filtered[ac], skb);

  		sta_info_recalc_tim(sta);

  
  		if (!timer_pending(&local->sta_cleanup))
  			mod_timer(&local->sta_cleanup,
  				  round_jiffies(jiffies +
  						STA_INFO_CLEANUP_INTERVAL));

  		return;
  	}

  	if (!test_sta_flag(sta, WLAN_STA_PS_STA) &&

  	    !(info->flags & IEEE80211_TX_INTFL_RETRIED)) {
  		/* Software retry the packet once */
  		info->flags |= IEEE80211_TX_INTFL_RETRIED;
  		ieee80211_add_pending_skb(local, skb);
  		return;
  	}

  #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
  	if (net_ratelimit())

  		wiphy_debug(local->hw.wiphy,
  			    "dropped TX filtered frame, queue_len=%d PS=%d @%lu
  ",

  			    skb_queue_len(&sta->tx_filtered[ac]),

  			    !!test_sta_flag(sta, WLAN_STA_PS_STA), jiffies);

  #endif
  	dev_kfree_skb(skb);
  }

  static void ieee80211_check_pending_bar(struct sta_info *sta, u8 *addr, u8 tid)
  {
  	struct tid_ampdu_tx *tid_tx;
  
  	tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
  	if (!tid_tx || !tid_tx->bar_pending)
  		return;
  
  	tid_tx->bar_pending = false;

  	ieee80211_send_bar(&sta->sdata->vif, addr, tid, tid_tx->failed_bar_ssn);

  }

  static void ieee80211_frame_acked(struct sta_info *sta, struct sk_buff *skb)
  {
  	struct ieee80211_mgmt *mgmt = (void *) skb->data;
  	struct ieee80211_local *local = sta->local;
  	struct ieee80211_sub_if_data *sdata = sta->sdata;

  	if (ieee80211_is_data_qos(mgmt->frame_control)) {
  		struct ieee80211_hdr *hdr = (void *) skb->data;
  		u8 *qc = ieee80211_get_qos_ctl(hdr);
  		u16 tid = qc[0] & 0xf;
  
  		ieee80211_check_pending_bar(sta, hdr->addr1, tid);
  	}

  	if (ieee80211_is_action(mgmt->frame_control) &&
  	    sdata->vif.type == NL80211_IFTYPE_STATION &&
  	    mgmt->u.action.category == WLAN_CATEGORY_HT &&
  	    mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS) {
  		/*
  		 * This update looks racy, but isn't -- if we come
  		 * here we've definitely got a station that we're
  		 * talking to, and on a managed interface that can
  		 * only be the AP. And the only other place updating
  		 * this variable is before we're associated.
  		 */
  		switch (mgmt->u.action.u.ht_smps.smps_control) {
  		case WLAN_HT_SMPS_CONTROL_DYNAMIC:
  			sta->sdata->u.mgd.ap_smps = IEEE80211_SMPS_DYNAMIC;
  			break;
  		case WLAN_HT_SMPS_CONTROL_STATIC:
  			sta->sdata->u.mgd.ap_smps = IEEE80211_SMPS_STATIC;
  			break;
  		case WLAN_HT_SMPS_CONTROL_DISABLED:
  		default: /* shouldn't happen since we don't send that */
  			sta->sdata->u.mgd.ap_smps = IEEE80211_SMPS_OFF;
  			break;
  		}
  
  		ieee80211_queue_work(&local->hw, &local->recalc_smps);
  	}
  }

  static void ieee80211_set_bar_pending(struct sta_info *sta, u8 tid, u16 ssn)
  {
  	struct tid_ampdu_tx *tid_tx;
  
  	tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
  	if (!tid_tx)
  		return;
  
  	tid_tx->failed_bar_ssn = ssn;
  	tid_tx->bar_pending = true;
  }

  static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info)
  {
  	int len = sizeof(struct ieee80211_radiotap_header);
  
  	/* IEEE80211_RADIOTAP_RATE rate */
  	if (info->status.rates[0].idx >= 0 &&
  	    !(info->status.rates[0].flags & IEEE80211_TX_RC_MCS))
  		len += 2;
  
  	/* IEEE80211_RADIOTAP_TX_FLAGS */
  	len += 2;
  
  	/* IEEE80211_RADIOTAP_DATA_RETRIES */
  	len += 1;

  	/* IEEE80211_TX_RC_MCS */
  	if (info->status.rates[0].idx >= 0 &&
  	    info->status.rates[0].flags & IEEE80211_TX_RC_MCS)
  		len += 3;

  	return len;
  }
  
  static void ieee80211_add_tx_radiotap_header(struct ieee80211_supported_band
  					     *sband, struct sk_buff *skb,
  					     int retry_count, int rtap_len)
  {
  	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  	struct ieee80211_radiotap_header *rthdr;
  	unsigned char *pos;

  	u16 txflags;

  
  	rthdr = (struct ieee80211_radiotap_header *) skb_push(skb, rtap_len);
  
  	memset(rthdr, 0, rtap_len);
  	rthdr->it_len = cpu_to_le16(rtap_len);
  	rthdr->it_present =
  		cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
  			    (1 << IEEE80211_RADIOTAP_DATA_RETRIES));
  	pos = (unsigned char *)(rthdr + 1);
  
  	/*
  	 * XXX: Once radiotap gets the bitmap reset thing the vendor
  	 *	extensions proposal contains, we can actually report
  	 *	the whole set of tries we did.
  	 */
  
  	/* IEEE80211_RADIOTAP_RATE */
  	if (info->status.rates[0].idx >= 0 &&
  	    !(info->status.rates[0].flags & IEEE80211_TX_RC_MCS)) {
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
  		*pos = sband->bitrates[info->status.rates[0].idx].bitrate / 5;
  		/* padding for tx flags */
  		pos += 2;
  	}
  
  	/* IEEE80211_RADIOTAP_TX_FLAGS */
  	txflags = 0;
  	if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
  	    !is_multicast_ether_addr(hdr->addr1))

  		txflags |= IEEE80211_RADIOTAP_F_TX_FAIL;

  
  	if ((info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS) ||
  	    (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT))

  		txflags |= IEEE80211_RADIOTAP_F_TX_CTS;

  	else if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)

  		txflags |= IEEE80211_RADIOTAP_F_TX_RTS;

  
  	put_unaligned_le16(txflags, pos);
  	pos += 2;
  
  	/* IEEE80211_RADIOTAP_DATA_RETRIES */
  	/* for now report the total retry_count */
  	*pos = retry_count;
  	pos++;

  
  	/* IEEE80211_TX_RC_MCS */
  	if (info->status.rates[0].idx >= 0 &&
  	    info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
  		pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
  			 IEEE80211_RADIOTAP_MCS_HAVE_GI |
  			 IEEE80211_RADIOTAP_MCS_HAVE_BW;
  		if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
  			pos[1] |= IEEE80211_RADIOTAP_MCS_SGI;
  		if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
  			pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40;
  		if (info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)
  			pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF;
  		pos[2] = info->status.rates[0].idx;
  		pos += 3;
  	}

  }

  /*
   * Use a static threshold for now, best value to be determined
   * by testing ...
   * Should it depend on:
   *  - on # of retransmissions
   *  - current throughput (higher value for higher tpt)?
   */
  #define STA_LOST_PKT_THRESHOLD	50

  void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
  {
  	struct sk_buff *skb2;
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  	struct ieee80211_local *local = hw_to_local(hw);
  	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);

  	__le16 fc;
  	struct ieee80211_supported_band *sband;

  	struct ieee80211_sub_if_data *sdata;
  	struct net_device *prev_dev = NULL;

  	struct sta_info *sta, *tmp;

  	int retry_count = -1, i;

  	int rates_idx = -1;

  	bool send_to_cooked;

  	bool acked;

  	struct ieee80211_bar *bar;
  	u16 tid;

  	int rtap_len;

  
  	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {

  		if (info->status.rates[i].idx < 0) {
  			break;
  		} else if (i >= hw->max_report_rates) {
  			/* the HW cannot have attempted that rate */

  			info->status.rates[i].idx = -1;
  			info->status.rates[i].count = 0;

  			break;

  		}
  
  		retry_count += info->status.rates[i].count;
  	}

  	rates_idx = i - 1;

  	if (retry_count < 0)
  		retry_count = 0;
  
  	rcu_read_lock();
  
  	sband = local->hw.wiphy->bands[info->band];

  	fc = hdr->frame_control;

  	for_each_sta_info(local, hdr->addr1, sta, tmp) {
  		/* skip wrong virtual interface */

  		if (memcmp(hdr->addr2, sta->sdata->vif.addr, ETH_ALEN))

  			continue;

  		if (info->flags & IEEE80211_TX_STATUS_EOSP)

  			clear_sta_flag(sta, WLAN_STA_SP);

  		acked = !!(info->flags & IEEE80211_TX_STAT_ACK);

  		if (!acked && test_sta_flag(sta, WLAN_STA_PS_STA)) {

  			/*
  			 * The STA is in power save mode, so assume
  			 * that this TX packet failed because of that.
  			 */
  			ieee80211_handle_filtered_frame(local, sta, skb);
  			rcu_read_unlock();
  			return;
  		}

  		if ((local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) &&
  		    (rates_idx != -1))
  			sta->last_tx_rate = info->status.rates[rates_idx];

  		if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
  		    (ieee80211_is_data_qos(fc))) {
  			u16 tid, ssn;
  			u8 *qc;
  
  			qc = ieee80211_get_qos_ctl(hdr);
  			tid = qc[0] & 0xf;
  			ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
  						& IEEE80211_SCTL_SEQ);

  			ieee80211_send_bar(&sta->sdata->vif, hdr->addr1,

  					   tid, ssn);
  		}

  		if (!acked && ieee80211_is_back_req(fc)) {

  			u16 control;

  			/*

  			 * BAR failed, store the last SSN and retry sending
  			 * the BAR when the next unicast transmission on the
  			 * same TID succeeds.

  			 */
  			bar = (struct ieee80211_bar *) skb->data;

  			control = le16_to_cpu(bar->control);
  			if (!(control & IEEE80211_BAR_CTRL_MULTI_TID)) {

  				u16 ssn = le16_to_cpu(bar->start_seq_num);

  				tid = (control &

  				       IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
  				      IEEE80211_BAR_CTRL_TID_INFO_SHIFT;

  
  				ieee80211_set_bar_pending(sta, tid, ssn);

  			}
  		}

  		if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
  			ieee80211_handle_filtered_frame(local, sta, skb);
  			rcu_read_unlock();
  			return;
  		} else {

  			if (!acked)

  				sta->tx_retry_failed++;
  			sta->tx_retry_count += retry_count;
  		}
  
  		rate_control_tx_status(local, sband, sta, skb);
  		if (ieee80211_vif_is_mesh(&sta->sdata->vif))
  			ieee80211s_update_metric(local, sta, skb);

  		if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked)

  			ieee80211_frame_acked(sta, skb);

  		if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) &&
  		    (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS))
  			ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data, acked);

  		if (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) {
  			if (info->flags & IEEE80211_TX_STAT_ACK) {
  				if (sta->lost_packets)
  					sta->lost_packets = 0;
  			} else if (++sta->lost_packets >= STA_LOST_PKT_THRESHOLD) {
  				cfg80211_cqm_pktloss_notify(sta->sdata->dev,
  							    sta->sta.addr,
  							    sta->lost_packets,
  							    GFP_ATOMIC);
  				sta->lost_packets = 0;
  			}
  		}

  	}
  
  	rcu_read_unlock();
  
  	ieee80211_led_tx(local, 0);
  
  	/* SNMP counters
  	 * Fragments are passed to low-level drivers as separate skbs, so these
  	 * are actually fragments, not frames. Update frame counters only for
  	 * the first fragment of the frame. */

  	if (info->flags & IEEE80211_TX_STAT_ACK) {

  		if (ieee80211_is_first_frag(hdr->seq_ctrl)) {

  			local->dot11TransmittedFrameCount++;
  			if (is_multicast_ether_addr(hdr->addr1))
  				local->dot11MulticastTransmittedFrameCount++;
  			if (retry_count > 0)
  				local->dot11RetryCount++;
  			if (retry_count > 1)
  				local->dot11MultipleRetryCount++;
  		}
  
  		/* This counter shall be incremented for an acknowledged MPDU
  		 * with an individual address in the address 1 field or an MPDU
  		 * with a multicast address in the address 1 field of type Data
  		 * or Management. */
  		if (!is_multicast_ether_addr(hdr->addr1) ||

  		    ieee80211_is_data(fc) ||
  		    ieee80211_is_mgmt(fc))

  			local->dot11TransmittedFragmentCount++;
  	} else {

  		if (ieee80211_is_first_frag(hdr->seq_ctrl))

  			local->dot11FailedCount++;
  	}

  	if (ieee80211_is_nullfunc(fc) && ieee80211_has_pm(fc) &&
  	    (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) &&
  	    !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
  	    local->ps_sdata && !(local->scanning)) {
  		if (info->flags & IEEE80211_TX_STAT_ACK) {
  			local->ps_sdata->u.mgd.flags |=
  					IEEE80211_STA_NULLFUNC_ACKED;

  		} else
  			mod_timer(&local->dynamic_ps_timer, jiffies +
  					msecs_to_jiffies(10));
  	}

  	if (info->flags & IEEE80211_TX_INTFL_NL80211_FRAME_TX) {

  		u64 cookie = (unsigned long)skb;

  		if (ieee80211_is_nullfunc(hdr->frame_control) ||
  		    ieee80211_is_qos_nullfunc(hdr->frame_control)) {
  			bool acked = info->flags & IEEE80211_TX_STAT_ACK;
  			cfg80211_probe_status(skb->dev, hdr->addr1,
  					      cookie, acked, GFP_ATOMIC);
  		} else {
  			struct ieee80211_work *wk;
  
  			rcu_read_lock();
  			list_for_each_entry_rcu(wk, &local->work_list, list) {
  				if (wk->type != IEEE80211_WORK_OFFCHANNEL_TX)
  					continue;
  				if (wk->offchan_tx.frame != skb)
  					continue;
  				wk->offchan_tx.status = true;
  				break;
  			}
  			rcu_read_unlock();
  			if (local->hw_roc_skb_for_status == skb) {
  				cookie = local->hw_roc_cookie ^ 2;
  				local->hw_roc_skb_for_status = NULL;
  			}

  			cfg80211_mgmt_tx_status(
  				skb->dev, cookie, skb->data, skb->len,
  				!!(info->flags & IEEE80211_TX_STAT_ACK),
  				GFP_ATOMIC);
  		}

  	}

  	if (unlikely(info->ack_frame_id)) {
  		struct sk_buff *ack_skb;
  		unsigned long flags;
  
  		spin_lock_irqsave(&local->ack_status_lock, flags);
  		ack_skb = idr_find(&local->ack_status_frames,
  				   info->ack_frame_id);
  		if (ack_skb)
  			idr_remove(&local->ack_status_frames,
  				   info->ack_frame_id);
  		spin_unlock_irqrestore(&local->ack_status_lock, flags);
  
  		/* consumes ack_skb */
  		if (ack_skb)
  			skb_complete_wifi_ack(ack_skb,
  				info->flags & IEEE80211_TX_STAT_ACK);
  	}

  	/* this was a transmitted frame, but now we want to reuse it */
  	skb_orphan(skb);

  	/* Need to make a copy before skb->cb gets cleared */
  	send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) ||

  			 !(ieee80211_is_data(fc));

  	/*
  	 * This is a bit racy but we can avoid a lot of work
  	 * with this test...
  	 */

  	if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) {

  		dev_kfree_skb(skb);
  		return;
  	}
  
  	/* send frame to monitor interfaces now */

  	rtap_len = ieee80211_tx_radiotap_len(info);
  	if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {

  		printk(KERN_ERR "ieee80211_tx_status: headroom too small
  ");
  		dev_kfree_skb(skb);
  		return;
  	}

  	ieee80211_add_tx_radiotap_header(sband, skb, retry_count, rtap_len);

  
  	/* XXX: is this sufficient for BPF? */
  	skb_set_mac_header(skb, 0);
  	skb->ip_summed = CHECKSUM_UNNECESSARY;
  	skb->pkt_type = PACKET_OTHERHOST;
  	skb->protocol = htons(ETH_P_802_2);
  	memset(skb->cb, 0, sizeof(skb->cb));
  
  	rcu_read_lock();
  	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
  		if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {

  			if (!ieee80211_sdata_running(sdata))

  				continue;
  
  			if ((sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) &&

  			    !send_to_cooked)

  				continue;
  
  			if (prev_dev) {
  				skb2 = skb_clone(skb, GFP_ATOMIC);
  				if (skb2) {
  					skb2->dev = prev_dev;

  					netif_rx(skb2);

  				}
  			}
  
  			prev_dev = sdata->dev;
  		}
  	}
  	if (prev_dev) {
  		skb->dev = prev_dev;

  		netif_rx(skb);

  		skb = NULL;
  	}
  	rcu_read_unlock();
  	dev_kfree_skb(skb);
  }
  EXPORT_SYMBOL(ieee80211_tx_status);

  
  void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets)
  {
  	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
  	cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
  				    num_packets, GFP_ATOMIC);
  }
  EXPORT_SYMBOL(ieee80211_report_low_ack);

  
  void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
  {

  	struct ieee80211_local *local = hw_to_local(hw);
  	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  
  	if (unlikely(info->ack_frame_id)) {
  		struct sk_buff *ack_skb;
  		unsigned long flags;
  
  		spin_lock_irqsave(&local->ack_status_lock, flags);
  		ack_skb = idr_find(&local->ack_status_frames,
  				   info->ack_frame_id);
  		if (ack_skb)
  			idr_remove(&local->ack_status_frames,
  				   info->ack_frame_id);
  		spin_unlock_irqrestore(&local->ack_status_lock, flags);
  
  		/* consumes ack_skb */
  		if (ack_skb)
  			dev_kfree_skb_any(ack_skb);
  	}

  	dev_kfree_skb_any(skb);
  }
  EXPORT_SYMBOL(ieee80211_free_txskb);