// SPDX-License-Identifier: GPL-2.0-only

  /*
   * 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>

   * Copyright 2013-2014  Intel Mobile Communications GmbH

   */

  #include <linux/export.h>

  #include <linux/etherdevice.h>

  #include <net/mac80211.h>

  #include <asm/unaligned.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))) {

  		ieee80211_free_txskb(hw, 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;

  	if (info->flags & (IEEE80211_TX_CTL_NO_PS_BUFFER |
  			   IEEE80211_TX_CTL_AMPDU)) {

  		ieee80211_free_txskb(&local->hw, skb);
  		return;
  	}

  	/*

  	 * 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->status_stats.filtered++;

  	/*
  	 * 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 = ieee80211_ac_from_tid(tid);

  	} 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);

  	ieee80211_clear_fast_xmit(sta);

  
  	/*
  	 * 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;
  	}

  	ps_dbg_ratelimited(sta->sdata,
  			   "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);

  	ieee80211_free_txskb(&local->hw, 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;

  	struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);

  	if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {

  		sta->status_stats.last_ack = jiffies;

  		if (txinfo->status.is_valid_ack_signal) {
  			sta->status_stats.last_ack_signal =
  					 (s8)txinfo->status.ack_signal;
  			sta->status_stats.ack_signal_filled = true;

  			ewma_avg_signal_add(&sta->status_stats.avg_ack_signal,
  					    -txinfo->status.ack_signal);

  		}
  	}

  	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) &&

  	    !ieee80211_has_protected(mgmt->frame_control) &&

  	    mgmt->u.action.category == WLAN_CATEGORY_HT &&

  	    mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS &&

  	    ieee80211_sdata_running(sdata)) {

  		enum ieee80211_smps_mode smps_mode;

  		switch (mgmt->u.action.u.ht_smps.smps_control) {
  		case WLAN_HT_SMPS_CONTROL_DYNAMIC:

  			smps_mode = IEEE80211_SMPS_DYNAMIC;

  			break;
  		case WLAN_HT_SMPS_CONTROL_STATIC:

  			smps_mode = IEEE80211_SMPS_STATIC;

  			break;
  		case WLAN_HT_SMPS_CONTROL_DISABLED:
  		default: /* shouldn't happen since we don't send that */

  			smps_mode = IEEE80211_SMPS_OFF;

  			break;
  		}

  		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
  			/*
  			 * 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 in managed mode is before association.
  			 */
  			sdata->smps_mode = smps_mode;
  			ieee80211_queue_work(&local->hw, &sdata->recalc_smps);
  		} else if (sdata->vif.type == NL80211_IFTYPE_AP ||
  			   sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
  			sta->known_smps_mode = smps_mode;
  		}

  	}
  }

  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,
  				     struct ieee80211_tx_status *status)

  {
  	int len = sizeof(struct ieee80211_radiotap_header);
  
  	/* IEEE80211_RADIOTAP_RATE rate */

  	if (status && status->rate && !(status->rate->flags &
  					(RATE_INFO_FLAGS_MCS |

  					 RATE_INFO_FLAGS_DMG |
  					 RATE_INFO_FLAGS_EDMG |

  					 RATE_INFO_FLAGS_VHT_MCS |
  					 RATE_INFO_FLAGS_HE_MCS)))
  		len += 2;
  	else if (info->status.rates[0].idx >= 0 &&
  		 !(info->status.rates[0].flags &
  		   (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS)))

  		len += 2;
  
  	/* IEEE80211_RADIOTAP_TX_FLAGS */
  	len += 2;
  
  	/* IEEE80211_RADIOTAP_DATA_RETRIES */
  	len += 1;

  	/* IEEE80211_RADIOTAP_MCS
  	 * IEEE80211_RADIOTAP_VHT */

  	if (status && status->rate) {
  		if (status->rate->flags & RATE_INFO_FLAGS_MCS)
  			len += 3;
  		else if (status->rate->flags & RATE_INFO_FLAGS_VHT_MCS)
  			len = ALIGN(len, 2) + 12;
  		else if (status->rate->flags & RATE_INFO_FLAGS_HE_MCS)
  			len = ALIGN(len, 2) + 12;
  	} else if (info->status.rates[0].idx >= 0) {

  		if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS)
  			len += 3;
  		else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS)
  			len = ALIGN(len, 2) + 12;
  	}

  	return len;
  }

  static void

  ieee80211_add_tx_radiotap_header(struct ieee80211_local *local,
  				 struct ieee80211_supported_band *sband,

  				 struct sk_buff *skb, int retry_count,

  				 int rtap_len, int shift,
  				 struct ieee80211_tx_status *status)

  {
  	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 legacy_rate = 0;

  	u16 txflags;

  	rthdr = 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 (status && status->rate) {
  		if (!(status->rate->flags & (RATE_INFO_FLAGS_MCS |

  					     RATE_INFO_FLAGS_DMG |
  					     RATE_INFO_FLAGS_EDMG |

  					     RATE_INFO_FLAGS_VHT_MCS |
  					     RATE_INFO_FLAGS_HE_MCS)))
  			legacy_rate = status->rate->legacy;
  	} else if (info->status.rates[0].idx >= 0 &&

  		 !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
  						  IEEE80211_TX_RC_VHT_MCS)))
  		legacy_rate =
  			sband->bitrates[info->status.rates[0].idx].bitrate;
  
  	if (legacy_rate) {

  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);

  		*pos = DIV_ROUND_UP(legacy_rate, 5 * (1 << shift));

  		/* 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_CTS_PROTECT)

  		txflags |= IEEE80211_RADIOTAP_F_TX_CTS;

  	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++;

  	if (status && status->rate &&
  	    (status->rate->flags & RATE_INFO_FLAGS_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 (status->rate->flags & RATE_INFO_FLAGS_SHORT_GI)
  			pos[1] |= IEEE80211_RADIOTAP_MCS_SGI;
  		if (status->rate->bw == RATE_INFO_BW_40)
  			pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40;
  		pos[2] = status->rate->mcs;
  		pos += 3;
  	} else if (status && status->rate &&
  		   (status->rate->flags & RATE_INFO_FLAGS_VHT_MCS)) {
  		u16 known = local->hw.radiotap_vht_details &
  			(IEEE80211_RADIOTAP_VHT_KNOWN_GI |
  			 IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH);
  
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
  
  		/* required alignment from rthdr */
  		pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);
  
  		/* u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_* */
  		put_unaligned_le16(known, pos);
  		pos += 2;
  
  		/* u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_* */
  		if (status->rate->flags & RATE_INFO_FLAGS_SHORT_GI)
  			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
  		pos++;
  
  		/* u8 bandwidth */
  		switch (status->rate->bw) {
  		case RATE_INFO_BW_160:
  			*pos = 11;
  			break;
  		case RATE_INFO_BW_80:

  			*pos = 4;

  			break;
  		case RATE_INFO_BW_40:
  			*pos = 1;
  			break;
  		default:
  			*pos = 0;
  			break;
  		}

  		pos++;

  
  		/* u8 mcs_nss[4] */
  		*pos = (status->rate->mcs << 4) | status->rate->nss;
  		pos += 4;
  
  		/* u8 coding */
  		pos++;
  		/* u8 group_id */
  		pos++;
  		/* u16 partial_aid */
  		pos += 2;
  	} else if (status && status->rate &&
  		   (status->rate->flags & RATE_INFO_FLAGS_HE_MCS)) {
  		struct ieee80211_radiotap_he *he;
  
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_HE);
  
  		/* required alignment from rthdr */
  		pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);
  		he = (struct ieee80211_radiotap_he *)pos;
  
  		he->data1 = cpu_to_le16(IEEE80211_RADIOTAP_HE_DATA1_FORMAT_SU |
  					IEEE80211_RADIOTAP_HE_DATA1_DATA_MCS_KNOWN |
  					IEEE80211_RADIOTAP_HE_DATA1_DATA_DCM_KNOWN |
  					IEEE80211_RADIOTAP_HE_DATA1_BW_RU_ALLOC_KNOWN);
  
  		he->data2 = cpu_to_le16(IEEE80211_RADIOTAP_HE_DATA2_GI_KNOWN);
  
  #define HE_PREP(f, val) le16_encode_bits(val, IEEE80211_RADIOTAP_HE_##f)
  
  		he->data6 |= HE_PREP(DATA6_NSTS, status->rate->nss);
  
  #define CHECK_GI(s) \
  	BUILD_BUG_ON(IEEE80211_RADIOTAP_HE_DATA5_GI_##s != \
  	(int)NL80211_RATE_INFO_HE_GI_##s)
  
  		CHECK_GI(0_8);
  		CHECK_GI(1_6);
  		CHECK_GI(3_2);
  
  		he->data3 |= HE_PREP(DATA3_DATA_MCS, status->rate->mcs);
  		he->data3 |= HE_PREP(DATA3_DATA_DCM, status->rate->he_dcm);
  
  		he->data5 |= HE_PREP(DATA5_GI, status->rate->he_gi);
  
  		switch (status->rate->bw) {
  		case RATE_INFO_BW_20:
  			he->data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
  					     IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_20MHZ);
  			break;
  		case RATE_INFO_BW_40:
  			he->data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
  					     IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_40MHZ);
  			break;
  		case RATE_INFO_BW_80:
  			he->data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
  					     IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_80MHZ);
  			break;
  		case RATE_INFO_BW_160:
  			he->data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
  					     IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_160MHZ);
  			break;
  		case RATE_INFO_BW_HE_RU:
  #define CHECK_RU_ALLOC(s) \
  	BUILD_BUG_ON(IEEE80211_RADIOTAP_HE_DATA5_DATA_BW_RU_ALLOC_##s##T != \
  	NL80211_RATE_INFO_HE_RU_ALLOC_##s + 4)
  
  			CHECK_RU_ALLOC(26);
  			CHECK_RU_ALLOC(52);
  			CHECK_RU_ALLOC(106);
  			CHECK_RU_ALLOC(242);
  			CHECK_RU_ALLOC(484);
  			CHECK_RU_ALLOC(996);
  			CHECK_RU_ALLOC(2x996);
  
  			he->data5 |= HE_PREP(DATA5_DATA_BW_RU_ALLOC,
  					     status->rate->he_ru_alloc + 4);
  			break;
  		default:
  			WARN_ONCE(1, "Invalid SU BW %d
  ", status->rate->bw);
  		}
  
  		pos += sizeof(struct ieee80211_radiotap_he);
  	}
  
  	if ((status && status->rate) || info->status.rates[0].idx < 0)

  		return;
  
  	/* IEEE80211_RADIOTAP_MCS
  	 * IEEE80211_RADIOTAP_VHT */
  	if (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;

  	} else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS) {
  		u16 known = local->hw.radiotap_vht_details &
  			(IEEE80211_RADIOTAP_VHT_KNOWN_GI |
  			 IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH);
  
  		rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
  
  		/* required alignment from rthdr */
  		pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);

  		/* u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_* */
  		put_unaligned_le16(known, pos);
  		pos += 2;
  
  		/* u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_* */
  		if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
  			*pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
  		pos++;
  
  		/* u8 bandwidth */
  		if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
  			*pos = 1;
  		else if (info->status.rates[0].flags & IEEE80211_TX_RC_80_MHZ_WIDTH)
  			*pos = 4;
  		else if (info->status.rates[0].flags & IEEE80211_TX_RC_160_MHZ_WIDTH)
  			*pos = 11;
  		else /* IEEE80211_TX_RC_{20_MHZ_WIDTH,FIXME:DUP_DATA} */
  			*pos = 0;
  		pos++;
  
  		/* u8 mcs_nss[4] */
  		*pos = (ieee80211_rate_get_vht_mcs(&info->status.rates[0]) << 4) |
  			ieee80211_rate_get_vht_nss(&info->status.rates[0]);
  		pos += 4;
  
  		/* u8 coding */
  		pos++;
  		/* u8 group_id */
  		pos++;
  		/* u16 partial_aid */
  		pos += 2;
  	}

  }

  /*
   * Handles the tx for TDLS teardown frames.
   * If the frame wasn't ACKed by the peer - it will be re-sent through the AP
   */
  static void ieee80211_tdls_td_tx_handle(struct ieee80211_local *local,
  					struct ieee80211_sub_if_data *sdata,
  					struct sk_buff *skb, u32 flags)
  {
  	struct sk_buff *teardown_skb;
  	struct sk_buff *orig_teardown_skb;
  	bool is_teardown = false;
  
  	/* Get the teardown data we need and free the lock */
  	spin_lock(&sdata->u.mgd.teardown_lock);
  	teardown_skb = sdata->u.mgd.teardown_skb;
  	orig_teardown_skb = sdata->u.mgd.orig_teardown_skb;
  	if ((skb == orig_teardown_skb) && teardown_skb) {
  		sdata->u.mgd.teardown_skb = NULL;
  		sdata->u.mgd.orig_teardown_skb = NULL;
  		is_teardown = true;
  	}
  	spin_unlock(&sdata->u.mgd.teardown_lock);
  
  	if (is_teardown) {
  		/* This mechanism relies on being able to get ACKs */

  		WARN_ON(!ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS));

  
  		/* Check if peer has ACKed */
  		if (flags & IEEE80211_TX_STAT_ACK) {
  			dev_kfree_skb_any(teardown_skb);
  		} else {
  			tdls_dbg(sdata,
  				 "TDLS Resending teardown through AP
  ");
  
  			ieee80211_subif_start_xmit(teardown_skb, skb->dev);
  		}
  	}
  }

  static struct ieee80211_sub_if_data *
  ieee80211_sdata_from_skb(struct ieee80211_local *local, struct sk_buff *skb)
  {
  	struct ieee80211_sub_if_data *sdata;
  
  	if (skb->dev) {
  		list_for_each_entry_rcu(sdata, &local->interfaces, list) {
  			if (!sdata->dev)
  				continue;
  
  			if (skb->dev == sdata->dev)
  				return sdata;
  		}
  
  		return NULL;
  	}
  
  	return rcu_dereference(local->p2p_sdata);
  }
  
  static void ieee80211_report_ack_skb(struct ieee80211_local *local,
  				     struct ieee80211_tx_info *info,
  				     bool acked, bool dropped)
  {
  	struct sk_buff *skb;
  	unsigned long flags;
  
  	spin_lock_irqsave(&local->ack_status_lock, flags);

  	skb = idr_remove(&local->ack_status_frames, info->ack_frame_id);

  	spin_unlock_irqrestore(&local->ack_status_lock, flags);
  
  	if (!skb)
  		return;

  	if (info->flags & IEEE80211_TX_INTFL_NL80211_FRAME_TX) {

  		u64 cookie = IEEE80211_SKB_CB(skb)->ack.cookie;

  		struct ieee80211_sub_if_data *sdata;

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

  
  		rcu_read_lock();
  		sdata = ieee80211_sdata_from_skb(local, skb);

  		if (sdata) {

  			if (ieee80211_is_any_nullfunc(hdr->frame_control))

  				cfg80211_probe_status(sdata->dev, hdr->addr1,

  						      cookie, acked,
  						      info->status.ack_signal,
  						      info->status.is_valid_ack_signal,

  						      GFP_ATOMIC);
  			else
  				cfg80211_mgmt_tx_status(&sdata->wdev, cookie,
  							skb->data, skb->len,
  							acked, GFP_ATOMIC);
  		}

  		rcu_read_unlock();
  
  		dev_kfree_skb_any(skb);

  	} else if (dropped) {
  		dev_kfree_skb_any(skb);

  	} else {
  		/* consumes skb */
  		skb_complete_wifi_ack(skb, acked);
  	}
  }

  static void ieee80211_report_used_skb(struct ieee80211_local *local,
  				      struct sk_buff *skb, bool dropped)
  {
  	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  	struct ieee80211_hdr *hdr = (void *)skb->data;
  	bool acked = info->flags & IEEE80211_TX_STAT_ACK;
  
  	if (dropped)
  		acked = false;

  	if (info->flags & IEEE80211_TX_INTFL_MLME_CONN_TX) {

  		struct ieee80211_sub_if_data *sdata;

  
  		rcu_read_lock();

  		sdata = ieee80211_sdata_from_skb(local, skb);

  		if (!sdata) {

  			skb->dev = NULL;

  		} else {

  			unsigned int hdr_size =
  				ieee80211_hdrlen(hdr->frame_control);
  
  			/* Check to see if packet is a TDLS teardown packet */
  			if (ieee80211_is_data(hdr->frame_control) &&
  			    (ieee80211_get_tdls_action(skb, hdr_size) ==
  			     WLAN_TDLS_TEARDOWN))
  				ieee80211_tdls_td_tx_handle(local, sdata, skb,
  							    info->flags);
  			else
  				ieee80211_mgd_conn_tx_status(sdata,
  							     hdr->frame_control,
  							     acked);

  		}
  
  		rcu_read_unlock();

  	} else if (info->ack_frame_id) {
  		ieee80211_report_ack_skb(local, info, acked, dropped);

  	}

  
  	if (!dropped && skb->destructor) {
  		skb->wifi_acked_valid = 1;
  		skb->wifi_acked = acked;
  	}

  
  	ieee80211_led_tx(local);

  
  	if (skb_has_frag_list(skb)) {
  		kfree_skb_list(skb_shinfo(skb)->frag_list);
  		skb_shinfo(skb)->frag_list = NULL;
  	}

  }

  /*
   * 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

  #define STA_LOST_TDLS_PKT_THRESHOLD	10
  #define STA_LOST_TDLS_PKT_TIME		(10*HZ) /* 10secs since last ACK */

  static void ieee80211_lost_packet(struct sta_info *sta,
  				  struct ieee80211_tx_info *info)

  {

  	/* If driver relies on its own algorithm for station kickout, skip
  	 * mac80211 packet loss mechanism.
  	 */
  	if (ieee80211_hw_check(&sta->local->hw, REPORTS_LOW_ACK))
  		return;

  	/* This packet was aggregated but doesn't carry status info */
  	if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
  	    !(info->flags & IEEE80211_TX_STAT_AMPDU))
  		return;

  	sta->status_stats.lost_packets++;
  	if (!sta->sta.tdls &&
  	    sta->status_stats.lost_packets < STA_LOST_PKT_THRESHOLD)

  		return;
  
  	/*
  	 * If we're in TDLS mode, make sure that all STA_LOST_TDLS_PKT_THRESHOLD
  	 * of the last packets were lost, and that no ACK was received in the
  	 * last STA_LOST_TDLS_PKT_TIME ms, before triggering the CQM packet-loss
  	 * mechanism.
  	 */
  	if (sta->sta.tdls &&

  	    (sta->status_stats.lost_packets < STA_LOST_TDLS_PKT_THRESHOLD ||

  	     time_before(jiffies,

  			 sta->status_stats.last_tdls_pkt_time +
  			 STA_LOST_TDLS_PKT_TIME)))

  		return;
  
  	cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,

  				    sta->status_stats.lost_packets, GFP_ATOMIC);
  	sta->status_stats.lost_packets = 0;

  }

  static int ieee80211_tx_get_rates(struct ieee80211_hw *hw,
  				  struct ieee80211_tx_info *info,
  				  int *retry_count)

  {

  	int rates_idx = -1;

  	int count = -1;
  	int i;

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

  		if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
  		    !(info->flags & IEEE80211_TX_STAT_AMPDU)) {
  			/* just the first aggr frame carry status info */
  			info->status.rates[i].idx = -1;
  			info->status.rates[i].count = 0;
  			break;
  		} else 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;

  		}

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

  	}

  	rates_idx = i - 1;

  	if (count < 0)
  		count = 0;
  
  	*retry_count = count;
  	return rates_idx;
  }

  void ieee80211_tx_monitor(struct ieee80211_local *local, struct sk_buff *skb,
  			  struct ieee80211_supported_band *sband,

  			  int retry_count, int shift, bool send_to_cooked,
  			  struct ieee80211_tx_status *status)

  {
  	struct sk_buff *skb2;

  	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  	struct ieee80211_sub_if_data *sdata;
  	struct net_device *prev_dev = NULL;
  	int rtap_len;
  
  	/* send frame to monitor interfaces now */

  	rtap_len = ieee80211_tx_radiotap_len(info, status);

  	if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
  		pr_err("ieee80211_tx_status: headroom too small
  ");
  		dev_kfree_skb(skb);
  		return;
  	}
  	ieee80211_add_tx_radiotap_header(local, sband, skb, retry_count,

  					 rtap_len, shift, status);

  
  	/* XXX: is this sufficient for BPF? */

  	skb_reset_mac_header(skb);

  	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);
  }

  static void __ieee80211_tx_status(struct ieee80211_hw *hw,
  				  struct ieee80211_tx_status *status)

  {

  	struct sk_buff *skb = status->skb;

  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  	struct ieee80211_local *local = hw_to_local(hw);

  	struct ieee80211_tx_info *info = status->info;
  	struct sta_info *sta;

  	__le16 fc;
  	struct ieee80211_supported_band *sband;

  	int retry_count;
  	int rates_idx;
  	bool send_to_cooked;
  	bool acked;
  	struct ieee80211_bar *bar;

  	int shift = 0;

  	int tid = IEEE80211_NUM_TIDS;

  
  	rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);

  	sband = local->hw.wiphy->bands[info->band];

  	fc = hdr->frame_control;

  	if (status->sta) {
  		sta = container_of(status->sta, struct sta_info, sta);

  		shift = ieee80211_vif_get_shift(&sta->sdata->vif);

  		if (info->flags & IEEE80211_TX_STATUS_EOSP)

  			clear_sta_flag(sta, WLAN_STA_SP);

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

  
  		/* mesh Peer Service Period support */
  		if (ieee80211_vif_is_mesh(&sta->sdata->vif) &&
  		    ieee80211_is_data_qos(fc))
  			ieee80211_mpsp_trigger_process(
  				ieee80211_get_qos_ctl(hdr), sta, true, acked);

  		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);

  			return;
  		}

  		if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL) &&

  		    (ieee80211_is_data(hdr->frame_control)) &&

  		    (rates_idx != -1))

  			sta->tx_stats.last_rate =
  				info->status.rates[rates_idx];

  		if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
  		    (ieee80211_is_data_qos(fc))) {

  			u16 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);

  		} else if (ieee80211_is_data_qos(fc)) {
  			u8 *qc = ieee80211_get_qos_ctl(hdr);
  
  			tid = qc[0] & 0xf;

  		}

  		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);

  			return;
  		} else {

  			if (!acked)

  				sta->status_stats.retry_failed++;
  			sta->status_stats.retry_count += retry_count;

  
  			if (ieee80211_is_data_present(fc)) {
  				if (!acked)

  					sta->status_stats.msdu_failed[tid]++;
  
  				sta->status_stats.msdu_retries[tid] +=
  					retry_count;

  			}

  		}

  		rate_control_tx_status(local, sband, status);

  		if (ieee80211_vif_is_mesh(&sta->sdata->vif))

  			ieee80211s_update_metric(local, sta, status);

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

  			ieee80211_frame_acked(sta, skb);

  		if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) &&

  		    ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))

  			ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data,
  						acked, info->status.tx_time);

  		if (info->status.tx_time &&
  		    wiphy_ext_feature_isset(local->hw.wiphy,
  					    NL80211_EXT_FEATURE_AIRTIME_FAIRNESS))
  			ieee80211_sta_register_airtime(&sta->sta, tid,
  						       info->status.tx_time, 0);

  		if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {

  			if (info->flags & IEEE80211_TX_STAT_ACK) {

  				if (sta->status_stats.lost_packets)
  					sta->status_stats.lost_packets = 0;

  
  				/* Track when last TDLS packet was ACKed */
  				if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))

  					sta->status_stats.last_tdls_pkt_time =
  						jiffies;

  			} else {

  				ieee80211_lost_packet(sta, info);

  			}
  		}

  	}

  	/* 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) ||
  	    (info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED)) {

  		if (ieee80211_is_first_frag(hdr->seq_ctrl)) {

  			I802_DEBUG_INC(local->dot11TransmittedFrameCount);

  			if (is_multicast_ether_addr(ieee80211_get_DA(hdr)))

  				I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);

  			if (retry_count > 0)

  				I802_DEBUG_INC(local->dot11RetryCount);

  			if (retry_count > 1)

  				I802_DEBUG_INC(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))

  			I802_DEBUG_INC(local->dot11TransmittedFragmentCount);

  	} else {

  		if (ieee80211_is_first_frag(hdr->seq_ctrl))

  			I802_DEBUG_INC(local->dot11FailedCount);

  	}

  	if (ieee80211_is_any_nullfunc(fc) &&

  	    ieee80211_has_pm(fc) &&

  	    ieee80211_hw_check(&local->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));
  	}

  	ieee80211_report_used_skb(local, skb, false);

  	/* 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 to monitor interfaces */

  	ieee80211_tx_monitor(local, skb, sband, retry_count, shift,
  			     send_to_cooked, status);

  }

  
  void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
  {
  	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
  	struct ieee80211_local *local = hw_to_local(hw);
  	struct ieee80211_tx_status status = {
  		.skb = skb,
  		.info = IEEE80211_SKB_CB(skb),
  	};
  	struct rhlist_head *tmp;
  	struct sta_info *sta;
  
  	rcu_read_lock();
  
  	for_each_sta_info(local, hdr->addr1, sta, tmp) {
  		/* skip wrong virtual interface */
  		if (!ether_addr_equal(hdr->addr2, sta->sdata->vif.addr))
  			continue;
  
  		status.sta = &sta->sta;
  		break;
  	}
  
  	__ieee80211_tx_status(hw, &status);
  	rcu_read_unlock();
  }

  EXPORT_SYMBOL(ieee80211_tx_status);

  void ieee80211_tx_status_ext(struct ieee80211_hw *hw,
  			     struct ieee80211_tx_status *status)

  {
  	struct ieee80211_local *local = hw_to_local(hw);

  	struct ieee80211_tx_info *info = status->info;
  	struct ieee80211_sta *pubsta = status->sta;

  	struct ieee80211_supported_band *sband;

  	int retry_count;
  	bool acked, noack_success;

  	if (status->skb)
  		return __ieee80211_tx_status(hw, status);
  
  	if (!status->sta)
  		return;

  	ieee80211_tx_get_rates(hw, info, &retry_count);
  
  	sband = hw->wiphy->bands[info->band];
  
  	acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
  	noack_success = !!(info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED);
  
  	if (pubsta) {
  		struct sta_info *sta;
  
  		sta = container_of(pubsta, struct sta_info, sta);
  
  		if (!acked)
  			sta->status_stats.retry_failed++;
  		sta->status_stats.retry_count += retry_count;
  
  		if (acked) {
  			sta->status_stats.last_ack = jiffies;
  
  			if (sta->status_stats.lost_packets)
  				sta->status_stats.lost_packets = 0;
  
  			/* Track when last TDLS packet was ACKed */
  			if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
  				sta->status_stats.last_tdls_pkt_time = jiffies;

  		} else if (test_sta_flag(sta, WLAN_STA_PS_STA)) {
  			return;

  		} else {
  			ieee80211_lost_packet(sta, info);
  		}

  		rate_control_tx_status(local, sband, status);

  		if (ieee80211_vif_is_mesh(&sta->sdata->vif))
  			ieee80211s_update_metric(local, sta, status);

  	}
  
  	if (acked || noack_success) {
  		I802_DEBUG_INC(local->dot11TransmittedFrameCount);
  		if (!pubsta)
  			I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
  		if (retry_count > 0)
  			I802_DEBUG_INC(local->dot11RetryCount);
  		if (retry_count > 1)
  			I802_DEBUG_INC(local->dot11MultipleRetryCount);
  	} else {
  		I802_DEBUG_INC(local->dot11FailedCount);
  	}
  }

  EXPORT_SYMBOL(ieee80211_tx_status_ext);

  void ieee80211_tx_rate_update(struct ieee80211_hw *hw,
  			      struct ieee80211_sta *pubsta,
  			      struct ieee80211_tx_info *info)
  {
  	struct ieee80211_local *local = hw_to_local(hw);
  	struct ieee80211_supported_band *sband = hw->wiphy->bands[info->band];
  	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
  	struct ieee80211_tx_status status = {
  		.info = info,
  		.sta = pubsta,
  	};
  
  	rate_control_tx_status(local, sband, &status);
  
  	if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL))
  		sta->tx_stats.last_rate = info->status.rates[0];
  }
  EXPORT_SYMBOL(ieee80211_tx_rate_update);

  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);

  	ieee80211_report_used_skb(local, skb, true);

  	dev_kfree_skb_any(skb);
  }
  EXPORT_SYMBOL(ieee80211_free_txskb);

  
  void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
  			      struct sk_buff_head *skbs)
  {
  	struct sk_buff *skb;
  
  	while ((skb = __skb_dequeue(skbs)))
  		ieee80211_free_txskb(hw, skb);
  }