iwlagn: free the Tx cmd when a non empty Tx queue is freed

When a non-empty Tx queueis freed, the buffer it contains must be
freed too. Since the Tx cmd are now allocated from a pool, the Tx
cmd must be freed too.

This patch avoids to destroy a non-empty pool of Tx cmd.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-agn.c

@@ -1522,6 +1522,8 @@ static void __iwl_down(struct iwl_priv *priv)
 	if (priv->shrd->mac80211_registered)
 		ieee80211_stop_queues(priv->hw);
 
+	iwl_trans_stop_device(trans(priv));
+
 	/* Clear out all status bits but a few that are stable across reset */
 	priv->shrd->status &=
 			test_bit(STATUS_RF_KILL_HW, &priv->shrd->status) <<
@@ -1533,8 +1535,6 @@ static void __iwl_down(struct iwl_priv *priv)
 			test_bit(STATUS_EXIT_PENDING, &priv->shrd->status) <<
 				STATUS_EXIT_PENDING;
 
-	iwl_trans_stop_device(trans(priv));
-
 	dev_kfree_skb(priv->beacon_skb);
 	priv->beacon_skb = NULL;
 }

drivers/net/wireless/iwlwifi/iwl-core.c

@@ -1876,3 +1876,12 @@ void iwl_nic_config(struct iwl_priv *priv)
 	priv->cfg->lib->nic_config(priv);
 
 }
+
+void iwl_free_skb(struct iwl_priv *priv, struct sk_buff *skb)
+{
+	struct ieee80211_tx_info *info;
+
+	info = IEEE80211_SKB_CB(skb);
+	kmem_cache_free(priv->tx_cmd_pool, (info->driver_data[1]));
+	dev_kfree_skb_any(skb);
+}

drivers/net/wireless/iwlwifi/iwl-shared.h

@@ -390,6 +390,7 @@ void iwl_stop_tx_ba_trans_ready(struct iwl_priv *priv,
 				u8 sta_id, u8 tid);
 void iwl_set_hw_rfkill_state(struct iwl_priv *priv, bool state);
 void iwl_nic_config(struct iwl_priv *priv);
+void iwl_free_skb(struct iwl_priv *priv, struct sk_buff *skb);
 void iwl_apm_stop(struct iwl_priv *priv);
 int iwl_apm_init(struct iwl_priv *priv);
 void iwlagn_fw_error(struct iwl_priv *priv, bool ondemand);

drivers/net/wireless/iwlwifi/iwl-trans-tx-pcie.c

@@ -225,9 +225,12 @@ void iwlagn_txq_free_tfd(struct iwl_trans *trans, struct iwl_tx_queue *txq,
 
 		skb = txq->skbs[index];
 
-		/* can be called from irqs-disabled context */
+		/* Can be called from irqs-disabled context
+		 * If skb is not NULL, it means that the whole queue is being
+		 * freed and that the queue is not empty - free the skb
+		 */
 		if (skb) {
-			dev_kfree_skb_any(skb);
+			iwl_free_skb(priv(trans), skb);
 			txq->skbs[index] = NULL;
 		}
 	}