mac80211: add helper to free TX skb

Drivers that need to drop a frame before it
can be transmitted will usually simply free
that frame. This is currently fine, but in
the future it'll be needed to tell mac80211
about this case, so add a new routine that
frees a TX skb.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

include/net/mac80211.h

@@ -1308,6 +1308,16 @@ ieee80211_get_alt_retry_rate(const struct ieee80211_hw *hw,
 	return &hw->wiphy->bands[c->band]->bitrates[c->control.rates[idx + 1].idx];
 }
 
+/**
+ * ieee80211_free_txskb - free TX skb
+ * @hw: the hardware
+ * @skb: the skb
+ *
+ * Free a transmit skb. Use this funtion when some failure
+ * to transmit happened and thus status cannot be reported.
+ */
+void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb);
+
 /**
  * DOC: Hardware crypto acceleration
  *

net/mac80211/status.c

@@ -609,3 +609,9 @@ void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets)
 				    num_packets, GFP_ATOMIC);
 }
 EXPORT_SYMBOL(ieee80211_report_low_ack);
+
+void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
+{
+	dev_kfree_skb_any(skb);
+}
+EXPORT_SYMBOL(ieee80211_free_txskb);