mac80211: make station management completely depend on vif

The station management currently uses the virtual
interface, but you cannot add the same station to
multiple virtual interfaces if you're communicating
with it in multiple ways.

This restriction should be lifted so that in the
future we can, for instance, support bluetooth 3
with an access point that mac80211 is already
associated to.

We can do that by requiring all sta_info_get users
to provide the virtual interface and making the RX
code aware that an address may match more than one
station struct. Thanks to the previous patches this
one isn't all that large and except for the RX and
TX status paths changes has low complexity.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index f237df4..5bae286 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1472,7 +1472,6 @@
 {
 	struct ieee80211_sub_if_data *sdata = rx->sdata;
 	struct net_device *dev = sdata->dev;
-	struct ieee80211_local *local = rx->local;
 	struct sk_buff *skb, *xmit_skb;
 	struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
 	struct sta_info *dsta;
@@ -1495,8 +1494,8 @@
 				printk(KERN_DEBUG "%s: failed to clone "
 				       "multicast frame\n", dev->name);
 		} else {
-			dsta = sta_info_get(local, skb->data);
-			if (dsta && dsta->sdata->dev == dev) {
+			dsta = sta_info_get(sdata, skb->data);
+			if (dsta) {
 				/*
 				 * The destination station is associated to
 				 * this AP (in this VLAN), so send the frame
@@ -2363,6 +2362,8 @@
 	int prepares;
 	struct ieee80211_sub_if_data *prev = NULL;
 	struct sk_buff *skb_new;
+	struct sta_info *sta, *tmp;
+	bool found_sta = false;
 
 	hdr = (struct ieee80211_hdr *)skb->data;
 	memset(&rx, 0, sizeof(rx));
@@ -2379,68 +2380,76 @@
 	ieee80211_parse_qos(&rx);
 	ieee80211_verify_alignment(&rx);
 
-	rx.sta = sta_info_get(local, hdr->addr2);
-	if (rx.sta)
-		rx.sdata = rx.sta->sdata;
+	if (ieee80211_is_data(hdr->frame_control)) {
+		for_each_sta_info(local, hdr->addr2, sta, tmp) {
+			rx.sta = sta;
+			found_sta = true;
+			rx.sdata = sta->sdata;
 
-	if (rx.sdata && ieee80211_is_data(hdr->frame_control)) {
-		rx.flags |= IEEE80211_RX_RA_MATCH;
-		prepares = prepare_for_handlers(rx.sdata, &rx, hdr);
-		if (prepares) {
+			rx.flags |= IEEE80211_RX_RA_MATCH;
+			prepares = prepare_for_handlers(rx.sdata, &rx, hdr);
+			if (prepares) {
+				if (status->flag & RX_FLAG_MMIC_ERROR) {
+					if (rx.flags & IEEE80211_RX_RA_MATCH)
+						ieee80211_rx_michael_mic_report(hdr, &rx);
+				} else
+					prev = rx.sdata;
+			}
+		}
+	}
+	if (!found_sta) {
+		list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+			if (!netif_running(sdata->dev))
+				continue;
+
+			if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
+			    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
+				continue;
+
+			rx.sta = sta_info_get(sdata, hdr->addr2);
+
+			rx.flags |= IEEE80211_RX_RA_MATCH;
+			prepares = prepare_for_handlers(sdata, &rx, hdr);
+
+			if (!prepares)
+				continue;
+
 			if (status->flag & RX_FLAG_MMIC_ERROR) {
+				rx.sdata = sdata;
 				if (rx.flags & IEEE80211_RX_RA_MATCH)
-					ieee80211_rx_michael_mic_report(hdr, &rx);
-			} else
-				prev = rx.sdata;
-		}
-	} else list_for_each_entry_rcu(sdata, &local->interfaces, list) {
-		if (!netif_running(sdata->dev))
-			continue;
+					ieee80211_rx_michael_mic_report(hdr,
+									&rx);
+				continue;
+			}
 
-		if (sdata->vif.type == NL80211_IFTYPE_MONITOR ||
-		    sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
-			continue;
+			/*
+			 * frame is destined for this interface, but if it's
+			 * not also for the previous one we handle that after
+			 * the loop to avoid copying the SKB once too much
+			 */
 
-		rx.flags |= IEEE80211_RX_RA_MATCH;
-		prepares = prepare_for_handlers(sdata, &rx, hdr);
+			if (!prev) {
+				prev = sdata;
+				continue;
+			}
 
-		if (!prepares)
-			continue;
+			/*
+			 * frame was destined for the previous interface
+			 * so invoke RX handlers for it
+			 */
 
-		if (status->flag & RX_FLAG_MMIC_ERROR) {
-			rx.sdata = sdata;
-			if (rx.flags & IEEE80211_RX_RA_MATCH)
-				ieee80211_rx_michael_mic_report(hdr, &rx);
-			continue;
-		}
-
-		/*
-		 * frame is destined for this interface, but if it's not
-		 * also for the previous one we handle that after the
-		 * loop to avoid copying the SKB once too much
-		 */
-
-		if (!prev) {
+			skb_new = skb_copy(skb, GFP_ATOMIC);
+			if (!skb_new) {
+				if (net_ratelimit())
+					printk(KERN_DEBUG "%s: failed to copy "
+					       "multicast frame for %s\n",
+					       wiphy_name(local->hw.wiphy),
+					       prev->dev->name);
+				continue;
+			}
+			ieee80211_invoke_rx_handlers(prev, &rx, skb_new, rate);
 			prev = sdata;
-			continue;
 		}
-
-		/*
-		 * frame was destined for the previous interface
-		 * so invoke RX handlers for it
-		 */
-
-		skb_new = skb_copy(skb, GFP_ATOMIC);
-		if (!skb_new) {
-			if (net_ratelimit())
-				printk(KERN_DEBUG "%s: failed to copy "
-				       "multicast frame for %s\n",
-				       wiphy_name(local->hw.wiphy),
-				       prev->dev->name);
-			continue;
-		}
-		ieee80211_invoke_rx_handlers(prev, &rx, skb_new, rate);
-		prev = sdata;
 	}
 	if (prev)
 		ieee80211_invoke_rx_handlers(prev, &rx, skb, rate);