mac80211: allow out-of-band EOSP notification

iwlwifi has a separate EOSP notification from
the device, and to make use of that properly
it needs to be passed to mac80211. To be able
to mix with tx_status_irqsafe and rx_irqsafe
it also needs to be an "_irqsafe" version in
the sense that it goes through the tasklet,
the actual flag clearing would be IRQ-safe
but doing it directly would cause reordering
issues.

This is needed in the case of a P2P GO going
into an absence period without transmitting
any frames that should be driver-released as
in this case there's no other way to inform
mac80211 that the service period ended. Note
that for drivers that don't use the _irqsafe
functions another version of this function
will be required.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 336ceb9..17b038a 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -325,6 +325,8 @@
 static void ieee80211_tasklet_handler(unsigned long data)
 {
 	struct ieee80211_local *local = (struct ieee80211_local *) data;
+	struct sta_info *sta, *tmp;
+	struct skb_eosp_msg_data *eosp_data;
 	struct sk_buff *skb;
 
 	while ((skb = skb_dequeue(&local->skb_queue)) ||
@@ -340,6 +342,18 @@
 			skb->pkt_type = 0;
 			ieee80211_tx_status(local_to_hw(local), skb);
 			break;
+		case IEEE80211_EOSP_MSG:
+			eosp_data = (void *)skb->cb;
+			for_each_sta_info(local, eosp_data->sta, sta, tmp) {
+				/* skip wrong virtual interface */
+				if (memcmp(eosp_data->iface,
+					   sta->sdata->vif.addr, ETH_ALEN))
+					continue;
+				clear_sta_flag(sta, WLAN_STA_SP);
+				break;
+			}
+			dev_kfree_skb(skb);
+			break;
 		default:
 			WARN(1, "mac80211: Packet is of unknown type %d\n",
 			     skb->pkt_type);