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path: root/drivers/net/wireless/iwlwifi/iwl-agn-tx.c
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Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-agn-tx.c')
-rw-r--r--drivers/net/wireless/iwlwifi/iwl-agn-tx.c360
1 files changed, 306 insertions, 54 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn-tx.c b/drivers/net/wireless/iwlwifi/iwl-agn-tx.c
index df1540ca610..c664c272655 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn-tx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn-tx.c
@@ -74,8 +74,8 @@ static void iwlagn_tx_cmd_build_basic(struct iwl_priv *priv,
else if (ieee80211_is_back_req(fc))
tx_flags |= TX_CMD_FLG_ACK_MSK | TX_CMD_FLG_IMM_BA_RSP_MASK;
else if (info->band == IEEE80211_BAND_2GHZ &&
- priv->cfg->bt_params &&
- priv->cfg->bt_params->advanced_bt_coexist &&
+ cfg(priv)->bt_params &&
+ cfg(priv)->bt_params->advanced_bt_coexist &&
(ieee80211_is_auth(fc) || ieee80211_is_assoc_req(fc) ||
ieee80211_is_reassoc_req(fc) ||
skb->protocol == cpu_to_be16(ETH_P_PAE)))
@@ -151,7 +151,7 @@ static void iwlagn_tx_cmd_build_rate(struct iwl_priv *priv,
if (ieee80211_is_data(fc)) {
tx_cmd->initial_rate_index = 0;
tx_cmd->tx_flags |= TX_CMD_FLG_STA_RATE_MSK;
-#ifdef CONFIG_IWLWIFI_DEVICE_SVTOOL
+#ifdef CONFIG_IWLWIFI_DEVICE_TESTMODE
if (priv->tm_fixed_rate) {
/*
* rate overwrite by testmode
@@ -164,7 +164,8 @@ static void iwlagn_tx_cmd_build_rate(struct iwl_priv *priv,
}
#endif
return;
- }
+ } else if (ieee80211_is_back_req(fc))
+ tx_cmd->tx_flags |= TX_CMD_FLG_STA_RATE_MSK;
/**
* If the current TX rate stored in mac80211 has the MCS bit set, it's
@@ -190,8 +191,8 @@ static void iwlagn_tx_cmd_build_rate(struct iwl_priv *priv,
rate_flags |= RATE_MCS_CCK_MSK;
/* Set up antennas */
- if (priv->cfg->bt_params &&
- priv->cfg->bt_params->advanced_bt_coexist &&
+ if (cfg(priv)->bt_params &&
+ cfg(priv)->bt_params->advanced_bt_coexist &&
priv->bt_full_concurrent) {
/* operated as 1x1 in full concurrency mode */
priv->mgmt_tx_ant = iwl_toggle_tx_ant(priv, priv->mgmt_tx_ant,
@@ -261,8 +262,8 @@ int iwlagn_tx_skb(struct iwl_priv *priv, struct sk_buff *skb)
__le16 fc;
u8 hdr_len;
- u16 len;
- u8 sta_id;
+ u16 len, seq_number = 0;
+ u8 sta_id, tid = IWL_MAX_TID_COUNT;
unsigned long flags;
bool is_agg = false;
@@ -286,6 +287,19 @@ int iwlagn_tx_skb(struct iwl_priv *priv, struct sk_buff *skb)
IWL_DEBUG_TX(priv, "Sending REASSOC frame\n");
#endif
+ if (unlikely(ieee80211_is_probe_resp(fc))) {
+ struct iwl_wipan_noa_data *noa_data =
+ rcu_dereference(priv->noa_data);
+
+ if (noa_data &&
+ pskb_expand_head(skb, 0, noa_data->length,
+ GFP_ATOMIC) == 0) {
+ memcpy(skb_put(skb, noa_data->length),
+ noa_data->data, noa_data->length);
+ hdr = (struct ieee80211_hdr *)skb->data;
+ }
+ }
+
hdr_len = ieee80211_hdrlen(fc);
/* For management frames use broadcast id to do not break aggregation */
@@ -354,9 +368,51 @@ int iwlagn_tx_skb(struct iwl_priv *priv, struct sk_buff *skb)
info->driver_data[0] = ctx;
info->driver_data[1] = dev_cmd;
- if (iwl_trans_tx(trans(priv), skb, dev_cmd, ctx->ctxid, sta_id))
+ if (ieee80211_is_data_qos(fc) && !ieee80211_is_qos_nullfunc(fc)) {
+ u8 *qc = NULL;
+ struct iwl_tid_data *tid_data;
+ qc = ieee80211_get_qos_ctl(hdr);
+ tid = qc[0] & IEEE80211_QOS_CTL_TID_MASK;
+ if (WARN_ON_ONCE(tid >= IWL_MAX_TID_COUNT))
+ goto drop_unlock_sta;
+ tid_data = &priv->tid_data[sta_id][tid];
+
+ /* aggregation is on for this <sta,tid> */
+ if (info->flags & IEEE80211_TX_CTL_AMPDU &&
+ tid_data->agg.state != IWL_AGG_ON) {
+ IWL_ERR(priv, "TX_CTL_AMPDU while not in AGG:"
+ " Tx flags = 0x%08x, agg.state = %d",
+ info->flags, tid_data->agg.state);
+ IWL_ERR(priv, "sta_id = %d, tid = %d seq_num = %d",
+ sta_id, tid, SEQ_TO_SN(tid_data->seq_number));
+ goto drop_unlock_sta;
+ }
+
+ /* We can receive packets from the stack in IWL_AGG_{ON,OFF}
+ * only. Check this here.
+ */
+ if (WARN_ONCE(tid_data->agg.state != IWL_AGG_ON &&
+ tid_data->agg.state != IWL_AGG_OFF,
+ "Tx while agg.state = %d", tid_data->agg.state))
+ goto drop_unlock_sta;
+
+ seq_number = tid_data->seq_number;
+ seq_number &= IEEE80211_SCTL_SEQ;
+ hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
+ hdr->seq_ctrl |= cpu_to_le16(seq_number);
+ seq_number += 0x10;
+ }
+
+ /* Copy MAC header from skb into command buffer */
+ memcpy(tx_cmd->hdr, hdr, hdr_len);
+
+ if (iwl_trans_tx(trans(priv), skb, dev_cmd, ctx->ctxid, sta_id, tid))
goto drop_unlock_sta;
+ if (ieee80211_is_data_qos(fc) && !ieee80211_is_qos_nullfunc(fc) &&
+ !ieee80211_has_morefrags(fc))
+ priv->tid_data[sta_id][tid].seq_number = seq_number;
+
spin_unlock(&priv->shrd->sta_lock);
spin_unlock_irqrestore(&priv->shrd->lock, flags);
@@ -381,10 +437,81 @@ drop_unlock_priv:
return -1;
}
+int iwlagn_tx_agg_stop(struct iwl_priv *priv, struct ieee80211_vif *vif,
+ struct ieee80211_sta *sta, u16 tid)
+{
+ struct iwl_tid_data *tid_data;
+ unsigned long flags;
+ int sta_id;
+
+ sta_id = iwl_sta_id(sta);
+
+ if (sta_id == IWL_INVALID_STATION) {
+ IWL_ERR(priv, "Invalid station for AGG tid %d\n", tid);
+ return -ENXIO;
+ }
+
+ spin_lock_irqsave(&priv->shrd->sta_lock, flags);
+
+ tid_data = &priv->tid_data[sta_id][tid];
+
+ switch (priv->tid_data[sta_id][tid].agg.state) {
+ case IWL_EMPTYING_HW_QUEUE_ADDBA:
+ /*
+ * This can happen if the peer stops aggregation
+ * again before we've had a chance to drain the
+ * queue we selected previously, i.e. before the
+ * session was really started completely.
+ */
+ IWL_DEBUG_HT(priv, "AGG stop before setup done\n");
+ goto turn_off;
+ case IWL_AGG_ON:
+ break;
+ default:
+ IWL_WARN(priv, "Stopping AGG while state not ON "
+ "or starting for %d on %d (%d)\n", sta_id, tid,
+ priv->tid_data[sta_id][tid].agg.state);
+ spin_unlock_irqrestore(&priv->shrd->sta_lock, flags);
+ return 0;
+ }
+
+ tid_data->agg.ssn = SEQ_TO_SN(tid_data->seq_number);
+
+ /* There are still packets for this RA / TID in the HW */
+ if (tid_data->agg.ssn != tid_data->next_reclaimed) {
+ IWL_DEBUG_TX_QUEUES(priv, "Can't proceed: ssn %d, "
+ "next_recl = %d",
+ tid_data->agg.ssn,
+ tid_data->next_reclaimed);
+ priv->tid_data[sta_id][tid].agg.state =
+ IWL_EMPTYING_HW_QUEUE_DELBA;
+ spin_unlock_irqrestore(&priv->shrd->sta_lock, flags);
+ return 0;
+ }
+
+ IWL_DEBUG_TX_QUEUES(priv, "Can proceed: ssn = next_recl = %d",
+ tid_data->agg.ssn);
+turn_off:
+ priv->tid_data[sta_id][tid].agg.state = IWL_AGG_OFF;
+
+ /* do not restore/save irqs */
+ spin_unlock(&priv->shrd->sta_lock);
+ spin_lock(&priv->shrd->lock);
+
+ iwl_trans_tx_agg_disable(trans(priv), sta_id, tid);
+
+ spin_unlock_irqrestore(&priv->shrd->lock, flags);
+
+ ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
+
+ return 0;
+}
+
int iwlagn_tx_agg_start(struct iwl_priv *priv, struct ieee80211_vif *vif,
struct ieee80211_sta *sta, u16 tid, u16 *ssn)
{
- struct iwl_vif_priv *vif_priv = (void *)vif->drv_priv;
+ struct iwl_tid_data *tid_data;
+ unsigned long flags;
int sta_id;
int ret;
@@ -399,7 +526,7 @@ int iwlagn_tx_agg_start(struct iwl_priv *priv, struct ieee80211_vif *vif,
if (unlikely(tid >= IWL_MAX_TID_COUNT))
return -EINVAL;
- if (priv->shrd->tid_data[sta_id][tid].agg.state != IWL_AGG_OFF) {
+ if (priv->tid_data[sta_id][tid].agg.state != IWL_AGG_OFF) {
IWL_ERR(priv, "Start AGG when state is not IWL_AGG_OFF !\n");
return -ENXIO;
}
@@ -408,27 +535,136 @@ int iwlagn_tx_agg_start(struct iwl_priv *priv, struct ieee80211_vif *vif,
if (ret)
return ret;
- ret = iwl_trans_tx_agg_alloc(trans(priv), vif_priv->ctx->ctxid, sta_id,
- tid, ssn);
+ spin_lock_irqsave(&priv->shrd->sta_lock, flags);
+
+ tid_data = &priv->tid_data[sta_id][tid];
+ tid_data->agg.ssn = SEQ_TO_SN(tid_data->seq_number);
+
+ *ssn = tid_data->agg.ssn;
+
+ ret = iwl_trans_tx_agg_alloc(trans(priv), sta_id, tid);
+ if (ret) {
+ spin_unlock_irqrestore(&priv->shrd->sta_lock, flags);
+ return ret;
+ }
+
+ if (*ssn == tid_data->next_reclaimed) {
+ IWL_DEBUG_TX_QUEUES(priv, "Can proceed: ssn = next_recl = %d",
+ tid_data->agg.ssn);
+ tid_data->agg.state = IWL_AGG_ON;
+ ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
+ } else {
+ IWL_DEBUG_TX_QUEUES(priv, "Can't proceed: ssn %d, "
+ "next_reclaimed = %d",
+ tid_data->agg.ssn,
+ tid_data->next_reclaimed);
+ tid_data->agg.state = IWL_EMPTYING_HW_QUEUE_ADDBA;
+ }
+
+ spin_unlock_irqrestore(&priv->shrd->sta_lock, flags);
return ret;
}
-int iwlagn_tx_agg_stop(struct iwl_priv *priv, struct ieee80211_vif *vif,
- struct ieee80211_sta *sta, u16 tid)
+int iwlagn_tx_agg_oper(struct iwl_priv *priv, struct ieee80211_vif *vif,
+ struct ieee80211_sta *sta, u16 tid, u8 buf_size)
{
- int sta_id;
- struct iwl_vif_priv *vif_priv = (void *)vif->drv_priv;
+ struct iwl_station_priv *sta_priv = (void *) sta->drv_priv;
+ struct iwl_rxon_context *ctx = iwl_rxon_ctx_from_vif(vif);
+ unsigned long flags;
+ u16 ssn;
- sta_id = iwl_sta_id(sta);
+ buf_size = min_t(int, buf_size, LINK_QUAL_AGG_FRAME_LIMIT_DEF);
- if (sta_id == IWL_INVALID_STATION) {
- IWL_ERR(priv, "Invalid station for AGG tid %d\n", tid);
- return -ENXIO;
+ spin_lock_irqsave(&priv->shrd->sta_lock, flags);
+ ssn = priv->tid_data[sta_priv->sta_id][tid].agg.ssn;
+ spin_unlock_irqrestore(&priv->shrd->sta_lock, flags);
+
+ iwl_trans_tx_agg_setup(trans(priv), ctx->ctxid, sta_priv->sta_id, tid,
+ buf_size, ssn);
+
+ /*
+ * If the limit is 0, then it wasn't initialised yet,
+ * use the default. We can do that since we take the
+ * minimum below, and we don't want to go above our
+ * default due to hardware restrictions.
+ */
+ if (sta_priv->max_agg_bufsize == 0)
+ sta_priv->max_agg_bufsize =
+ LINK_QUAL_AGG_FRAME_LIMIT_DEF;
+
+ /*
+ * Even though in theory the peer could have different
+ * aggregation reorder buffer sizes for different sessions,
+ * our ucode doesn't allow for that and has a global limit
+ * for each station. Therefore, use the minimum of all the
+ * aggregation sessions and our default value.
+ */
+ sta_priv->max_agg_bufsize =
+ min(sta_priv->max_agg_bufsize, buf_size);
+
+ if (cfg(priv)->ht_params &&
+ cfg(priv)->ht_params->use_rts_for_aggregation) {
+ /*
+ * switch to RTS/CTS if it is the prefer protection
+ * method for HT traffic
+ */
+
+ sta_priv->lq_sta.lq.general_params.flags |=
+ LINK_QUAL_FLAGS_SET_STA_TLC_RTS_MSK;
}
+ priv->agg_tids_count++;
+ IWL_DEBUG_HT(priv, "priv->agg_tids_count = %u\n",
+ priv->agg_tids_count);
+
+ sta_priv->lq_sta.lq.agg_params.agg_frame_cnt_limit =
+ sta_priv->max_agg_bufsize;
- return iwl_trans_tx_agg_disable(trans(priv), vif_priv->ctx->ctxid,
- sta_id, tid);
+ IWL_INFO(priv, "Tx aggregation enabled on ra = %pM tid = %d\n",
+ sta->addr, tid);
+
+ return iwl_send_lq_cmd(priv, ctx,
+ &sta_priv->lq_sta.lq, CMD_ASYNC, false);
+}
+
+static void iwlagn_check_ratid_empty(struct iwl_priv *priv, int sta_id, u8 tid)
+{
+ struct iwl_tid_data *tid_data = &priv->tid_data[sta_id][tid];
+ enum iwl_rxon_context_id ctx;
+ struct ieee80211_vif *vif;
+ u8 *addr;
+
+ lockdep_assert_held(&priv->shrd->sta_lock);
+
+ addr = priv->stations[sta_id].sta.sta.addr;
+ ctx = priv->stations[sta_id].ctxid;
+ vif = priv->contexts[ctx].vif;
+
+ switch (priv->tid_data[sta_id][tid].agg.state) {
+ case IWL_EMPTYING_HW_QUEUE_DELBA:
+ /* There are no packets for this RA / TID in the HW any more */
+ if (tid_data->agg.ssn == tid_data->next_reclaimed) {
+ IWL_DEBUG_TX_QUEUES(priv,
+ "Can continue DELBA flow ssn = next_recl ="
+ " %d", tid_data->next_reclaimed);
+ iwl_trans_tx_agg_disable(trans(priv), sta_id, tid);
+ tid_data->agg.state = IWL_AGG_OFF;
+ ieee80211_stop_tx_ba_cb_irqsafe(vif, addr, tid);
+ }
+ break;
+ case IWL_EMPTYING_HW_QUEUE_ADDBA:
+ /* There are no packets for this RA / TID in the HW any more */
+ if (tid_data->agg.ssn == tid_data->next_reclaimed) {
+ IWL_DEBUG_TX_QUEUES(priv,
+ "Can continue ADDBA flow ssn = next_recl ="
+ " %d", tid_data->next_reclaimed);
+ tid_data->agg.state = IWL_AGG_ON;
+ ieee80211_start_tx_ba_cb_irqsafe(vif, addr, tid);
+ }
+ break;
+ default:
+ break;
+ }
}
static void iwlagn_non_agg_tx_status(struct iwl_priv *priv,
@@ -568,7 +804,7 @@ static void iwl_rx_reply_tx_agg(struct iwl_priv *priv,
IWLAGN_TX_RES_TID_POS;
int sta_id = (tx_resp->ra_tid & IWLAGN_TX_RES_RA_MSK) >>
IWLAGN_TX_RES_RA_POS;
- struct iwl_ht_agg *agg = &priv->shrd->tid_data[sta_id][tid].agg;
+ struct iwl_ht_agg *agg = &priv->tid_data[sta_id][tid].agg;
u32 status = le16_to_cpu(tx_resp->status.status);
int i;
@@ -584,8 +820,8 @@ static void iwl_rx_reply_tx_agg(struct iwl_priv *priv,
* notification again.
*/
if (tx_resp->bt_kill_count && tx_resp->frame_count == 1 &&
- priv->cfg->bt_params &&
- priv->cfg->bt_params->advanced_bt_coexist) {
+ cfg(priv)->bt_params &&
+ cfg(priv)->bt_params->advanced_bt_coexist) {
IWL_DEBUG_COEX(priv, "receive reply tx w/ bt_kill\n");
}
@@ -758,7 +994,7 @@ int iwlagn_rx_reply_tx(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb,
struct iwlagn_tx_resp *tx_resp = (void *)&pkt->u.raw[0];
struct ieee80211_hdr *hdr;
u32 status = le16_to_cpu(tx_resp->status.status);
- u32 ssn = iwlagn_get_scd_ssn(tx_resp);
+ u16 ssn = iwlagn_get_scd_ssn(tx_resp);
int tid;
int sta_id;
int freed;
@@ -780,10 +1016,34 @@ int iwlagn_rx_reply_tx(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb,
iwl_rx_reply_tx_agg(priv, tx_resp);
if (tx_resp->frame_count == 1) {
+ u16 next_reclaimed = le16_to_cpu(tx_resp->seq_ctl);
+ next_reclaimed = SEQ_TO_SN(next_reclaimed + 0x10);
+
+ if (is_agg) {
+ /* If this is an aggregation queue, we can rely on the
+ * ssn since the wifi sequence number corresponds to
+ * the index in the TFD ring (%256).
+ * The seq_ctl is the sequence control of the packet
+ * to which this Tx response relates. But if there is a
+ * hole in the bitmap of the BA we received, this Tx
+ * response may allow to reclaim the hole and all the
+ * subsequent packets that were already acked.
+ * In that case, seq_ctl != ssn, and the next packet
+ * to be reclaimed will be ssn and not seq_ctl.
+ */
+ next_reclaimed = ssn;
+ }
+
__skb_queue_head_init(&skbs);
+ priv->tid_data[sta_id][tid].next_reclaimed = next_reclaimed;
+
+ IWL_DEBUG_TX_REPLY(priv, "Next reclaimed packet:%d",
+ next_reclaimed);
+
/*we can free until ssn % q.n_bd not inclusive */
- iwl_trans_reclaim(trans(priv), sta_id, tid, txq_id,
- ssn, status, &skbs);
+ WARN_ON(iwl_trans_reclaim(trans(priv), sta_id, tid, txq_id,
+ ssn, status, &skbs));
+ iwlagn_check_ratid_empty(priv, sta_id, tid);
freed = 0;
while (!skb_queue_empty(&skbs)) {
skb = __skb_dequeue(&skbs);
@@ -803,7 +1063,8 @@ int iwlagn_rx_reply_tx(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb,
iwl_is_associated_ctx(ctx) && ctx->vif &&
ctx->vif->type == NL80211_IFTYPE_STATION) {
ctx->last_tx_rejected = true;
- iwl_trans_stop_queue(trans(priv), txq_id);
+ iwl_trans_stop_queue(trans(priv), txq_id,
+ "Tx on passive channel");
IWL_DEBUG_TX_REPLY(priv,
"TXQ %d status %s (0x%08x) "
@@ -877,27 +1138,24 @@ int iwlagn_rx_reply_compressed_ba(struct iwl_priv *priv,
sta_id = ba_resp->sta_id;
tid = ba_resp->tid;
- agg = &priv->shrd->tid_data[sta_id][tid].agg;
+ agg = &priv->tid_data[sta_id][tid].agg;
spin_lock_irqsave(&priv->shrd->sta_lock, flags);
- if (unlikely(agg->txq_id != scd_flow)) {
- /*
- * FIXME: this is a uCode bug which need to be addressed,
- * log the information and return for now!
- * since it is possible happen very often and in order
- * not to fill the syslog, don't enable the logging by default
- */
- IWL_DEBUG_TX_REPLY(priv,
- "BA scd_flow %d does not match txq_id %d\n",
- scd_flow, agg->txq_id);
+ if (unlikely(!agg->wait_for_ba)) {
+ if (unlikely(ba_resp->bitmap))
+ IWL_ERR(priv, "Received BA when not expected\n");
spin_unlock_irqrestore(&priv->shrd->sta_lock, flags);
return 0;
}
- if (unlikely(!agg->wait_for_ba)) {
- if (unlikely(ba_resp->bitmap))
- IWL_ERR(priv, "Received BA when not expected\n");
+ __skb_queue_head_init(&reclaimed_skbs);
+
+ /* Release all TFDs before the SSN, i.e. all TFDs in front of
+ * block-ack window (we assume that they've been successfully
+ * transmitted ... if not, it's too late anyway). */
+ if (iwl_trans_reclaim(trans(priv), sta_id, tid, scd_flow,
+ ba_resp_scd_ssn, 0, &reclaimed_skbs)) {
spin_unlock_irqrestore(&priv->shrd->sta_lock, flags);
return 0;
}
@@ -909,11 +1167,9 @@ int iwlagn_rx_reply_compressed_ba(struct iwl_priv *priv,
ba_resp->sta_id);
IWL_DEBUG_TX_REPLY(priv, "TID = %d, SeqCtl = %d, bitmap = 0x%llx, "
"scd_flow = %d, scd_ssn = %d\n",
- ba_resp->tid,
- ba_resp->seq_ctl,
+ ba_resp->tid, le16_to_cpu(ba_resp->seq_ctl),
(unsigned long long)le64_to_cpu(ba_resp->bitmap),
- ba_resp->scd_flow,
- ba_resp->scd_ssn);
+ scd_flow, ba_resp_scd_ssn);
/* Mark that the expected block-ack response arrived */
agg->wait_for_ba = false;
@@ -932,13 +1188,9 @@ int iwlagn_rx_reply_compressed_ba(struct iwl_priv *priv,
IWL_DEBUG_HT(priv, "agg frames sent:%d, acked:%d\n",
ba_resp->txed, ba_resp->txed_2_done);
- __skb_queue_head_init(&reclaimed_skbs);
+ priv->tid_data[sta_id][tid].next_reclaimed = ba_resp_scd_ssn;
- /* Release all TFDs before the SSN, i.e. all TFDs in front of
- * block-ack window (we assume that they've been successfully
- * transmitted ... if not, it's too late anyway). */
- iwl_trans_reclaim(trans(priv), sta_id, tid, scd_flow, ba_resp_scd_ssn,
- 0, &reclaimed_skbs);
+ iwlagn_check_ratid_empty(priv, sta_id, tid);
freed = 0;
while (!skb_queue_empty(&reclaimed_skbs)) {