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linux-next/net/mac80211/status.c

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// 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\n",
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\n", 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\n");
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);
u16 tx_time_est = ieee80211_info_get_tx_time_est(info);
struct ieee80211_hdr *hdr = (void *)skb->data;
bool acked = info->flags & IEEE80211_TX_STAT_ACK;
if (dropped)
acked = false;
if (tx_time_est) {
struct sta_info *sta;
rcu_read_lock();
sta = sta_info_get_by_addrs(local, hdr->addr1, hdr->addr2);
ieee80211_sta_update_pending_airtime(local, sta,
skb_get_queue_mapping(skb),
tx_time_est,
true);
rcu_read_unlock();
}
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\n");
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;
bool noack_success;
struct ieee80211_bar *bar;
int shift = 0;
int tid = IEEE80211_NUM_TIDS;
u16 tx_time_est;
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);
noack_success = !!(info->flags &
IEEE80211_TX_STAT_NOACK_TRANSMITTED);
/* 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 && !noack_success)
sta->status_stats.retry_failed++;
sta->status_stats.retry_count += retry_count;
if (ieee80211_is_data_present(fc)) {
if (!acked && !noack_success)
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);
mac80211: Add airtime accounting and scheduling to TXQs This adds airtime accounting and scheduling to the mac80211 TXQ scheduler. A new callback, ieee80211_sta_register_airtime(), is added that drivers can call to report airtime usage for stations. When airtime information is present, mac80211 will schedule TXQs (through ieee80211_next_txq()) in a way that enforces airtime fairness between active stations. This scheduling works the same way as the ath9k in-driver airtime fairness scheduling. If no airtime usage is reported by the driver, the scheduler will default to round-robin scheduling. For drivers that don't control TXQ scheduling in software, a new API function, ieee80211_txq_may_transmit(), is added which the driver can use to check if the TXQ is eligible for transmission, or should be throttled to enforce fairness. Calls to this function must also be enclosed in ieee80211_txq_schedule_{start,end}() calls to ensure proper locking. The API ieee80211_txq_may_transmit() also ensures that TXQ list will be aligned aginst driver's own round-robin scheduler list. i.e it rotates the TXQ list till it makes the requested node becomes the first entry in TXQ list. Thus both the TXQ list and driver's list are in sync. Co-developed-by: Rajkumar Manoharan <rmanohar@codeaurora.org> Signed-off-by: Louie Lu <git@louie.lu> [added debugfs write op to reset airtime counter] Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk> Signed-off-by: Rajkumar Manoharan <rmanohar@codeaurora.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2018-12-19 09:02:08 +08:00
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 ((tx_time_est = ieee80211_info_get_tx_time_est(info)) > 0) {
/* Do this here to avoid the expensive lookup of the sta
* in ieee80211_report_used_skb().
*/
ieee80211_sta_update_pending_airtime(local, sta,
skb_get_queue_mapping(skb),
tx_time_est,
true);
ieee80211_info_set_tx_time_est(info, 0);
}
if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
if (acked) {
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 (noack_success) {
/* nothing to do here, do not account as lost */
} 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 sta_info *sta;
rcu_read_lock();
sta = sta_info_get_by_addrs(local, hdr->addr1, hdr->addr2);
if (sta)
status.sta = &sta->sta;
__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 && !noack_success)
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 if (noack_success) {
/* nothing to do here, do not account as lost */
} 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_tx_status_8023(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
struct sk_buff *skb)
{
struct ieee80211_local *local = hw_to_local(hw);
struct ieee80211_sub_if_data *sdata;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct sta_info *sta;
int retry_count;
int rates_idx;
bool acked;
sdata = vif_to_sdata(vif);
acked = info->flags & IEEE80211_TX_STAT_ACK;
rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);
rcu_read_lock();
if (ieee80211_lookup_ra_sta(sdata, skb, &sta))
goto counters_update;
if (IS_ERR(sta))
goto counters_update;
if (!acked)
sta->status_stats.retry_failed++;
if (rates_idx != -1)
sta->tx_stats.last_rate = info->status.rates[rates_idx];
sta->status_stats.retry_count += retry_count;
if (ieee80211_hw_check(hw, REPORTS_TX_ACK_STATUS)) {
if (acked && vif->type == NL80211_IFTYPE_STATION)
ieee80211_sta_reset_conn_monitor(sdata);
sta->status_stats.last_ack = jiffies;
if (info->flags & IEEE80211_TX_STAT_ACK) {
if (sta->status_stats.lost_packets)
sta->status_stats.lost_packets = 0;
if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
sta->status_stats.last_tdls_pkt_time = jiffies;
} else {
ieee80211_lost_packet(sta, info);
}
}
counters_update:
rcu_read_unlock();
ieee80211_led_tx(local);
if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
!(info->flags & IEEE80211_TX_STAT_NOACK_TRANSMITTED))
goto skip_stats_update;
I802_DEBUG_INC(local->dot11TransmittedFrameCount);
if (is_multicast_ether_addr(skb->data))
I802_DEBUG_INC(local->dot11MulticastTransmittedFrameCount);
if (retry_count > 0)
I802_DEBUG_INC(local->dot11RetryCount);
if (retry_count > 1)
I802_DEBUG_INC(local->dot11MultipleRetryCount);
skip_stats_update:
ieee80211_report_used_skb(local, skb, false);
dev_kfree_skb(skb);
}
EXPORT_SYMBOL(ieee80211_tx_status_8023);
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);
}