mac80211: use common cleanup for user/!user_mpm

We've accumulated a couple of different fixes now to mesh_sta_cleanup()
due to the different paths that user_mpm and !user_mpm cases take -- one
fix to flush nexthop paths and one to fix the counting.

The only caller of mesh_plink_deactivate() is mesh_sta_cleanup(), so we
can push the user_mpm checks down into there in order to share more
code.

In doing so, we can remove an extra call to mesh_path_flush_by_nexthop()
and the (unnecessary) call to mesh_accept_plinks_update().  This will
also ensure the powersaving state code gets called in the user_mpm case.

The only cleanup tasks we need to avoid when MPM is in user-space
are sending the peering frames and stopping the plink timer, so wrap
those in the appropriate check.
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>

net/mac80211/mesh.c

@@ -148,25 +148,7 @@ u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
 void mesh_sta_cleanup(struct sta_info *sta)
 {
 	struct ieee80211_sub_if_data *sdata = sta->sdata;
-	u32 changed = 0;
-
-	/*
-	 * maybe userspace handles peer allocation and peering, but in either
-	 * case the beacon is still generated by the kernel and we might need
-	 * an update.
-	 */
-	if (sdata->u.mesh.user_mpm &&
-	    sta->mesh->plink_state == NL80211_PLINK_ESTAB)
-		changed |= mesh_plink_dec_estab_count(sdata);
-	changed |= mesh_accept_plinks_update(sdata);
-	if (!sdata->u.mesh.user_mpm) {
-		changed |= mesh_plink_deactivate(sta);
-		del_timer_sync(&sta->mesh->plink_timer);
-	}
-
-	/* make sure no readers can access nexthop sta from here on */
-	mesh_path_flush_by_nexthop(sta);
-	synchronize_net();
+	u32 changed = mesh_plink_deactivate(sta);
 
 	if (changed)
 		ieee80211_mbss_info_change_notify(sdata, changed);

net/mac80211/mesh_plink.c

@@ -370,13 +370,21 @@ u32 mesh_plink_deactivate(struct sta_info *sta)
 
 	spin_lock_bh(&sta->mesh->plink_lock);
 	changed = __mesh_plink_deactivate(sta);
+
+	if (!sdata->u.mesh.user_mpm) {
 		sta->mesh->reason = WLAN_REASON_MESH_PEER_CANCELED;
 		mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_CLOSE,
-			    sta->sta.addr, sta->mesh->llid, sta->mesh->plid,
-			    sta->mesh->reason);
+				    sta->sta.addr, sta->mesh->llid,
+				    sta->mesh->plid, sta->mesh->reason);
+	}
 	spin_unlock_bh(&sta->mesh->plink_lock);
+	if (!sdata->u.mesh.user_mpm)
+		del_timer_sync(&sta->mesh->plink_timer);
 	mesh_path_flush_by_nexthop(sta);
 
+	/* make sure no readers can access nexthop sta from here on */
+	synchronize_net();
+
 	return changed;
 }