[PATCH 3.16.y-ckt 059/129] mac80211: Requeue work after scan complete for all VIF types.

[Luis Henriques]

3.16.7-ckt25 -stable review patch.  If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Sachin Kulkarni <Sachin.Kulkarni@xxxxxxxxxx>

commit 4fa11ec726a32ea6dd768dbb2e2af3453a98ec0a upstream.

During a sw scan ieee80211_iface_work ignores work items for all vifs.
However after the scan complete work is requeued only for STA, ADHOC
and MESH iftypes.

This occasionally results in event processing getting delayed/not
processed for iftype AP when it coexists with a STA. This can result
in data halt and eventually disconnection on the AP interface.

Signed-off-by: Sachin Kulkarni <Sachin.Kulkarni@xxxxxxxxxx>
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques@xxxxxxxxxxxxx>
---
 net/mac80211/ibss.c |  1 -
 net/mac80211/mesh.c | 11 -----------
 net/mac80211/mesh.h |  4 ----
 net/mac80211/mlme.c |  2 --
 net/mac80211/scan.c | 12 +++++++++++-
 5 files changed, 11 insertions(+), 19 deletions(-)

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 851bbf156a8f..f8ee7336d0b9 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -1628,7 +1628,6 @@ void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
 		if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
 			continue;
 		sdata->u.ibss.last_scan_completed = jiffies;
-		ieee80211_queue_work(&local->hw, &sdata->work);
 	}
 	mutex_unlock(&local->iflist_mtx);
 }
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index e64982ce0f8f..3e328131afb5 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -1297,17 +1297,6 @@ out:
 	sdata_unlock(sdata);
 }
 
-void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local)
-{
-	struct ieee80211_sub_if_data *sdata;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(sdata, &local->interfaces, list)
-		if (ieee80211_vif_is_mesh(&sdata->vif) &&
-		    ieee80211_sdata_running(sdata))
-			ieee80211_queue_work(&local->hw, &sdata->work);
-	rcu_read_unlock();
-}
 
 void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
 {
diff --git a/net/mac80211/mesh.h b/net/mac80211/mesh.h
index f39a19f9090f..1ca355b5b608 100644
--- a/net/mac80211/mesh.h
+++ b/net/mac80211/mesh.h
@@ -355,14 +355,10 @@ static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
 	return sdata->u.mesh.mesh_pp_id == IEEE80211_PATH_PROTOCOL_HWMP;
 }
 
-void ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local);
-
 void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata);
 void mesh_sync_adjust_tbtt(struct ieee80211_sub_if_data *sdata);
 void ieee80211s_stop(void);
 #else
-static inline void
-ieee80211_mesh_notify_scan_completed(struct ieee80211_local *local) {}
 static inline bool mesh_path_sel_is_hwmp(struct ieee80211_sub_if_data *sdata)
 { return false; }
 static inline void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index db469ec12387..ff3dac855100 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -3614,8 +3614,6 @@ static void ieee80211_restart_sta_timer(struct ieee80211_sub_if_data *sdata)
 		if (!(flags & IEEE80211_HW_CONNECTION_MONITOR))
 			ieee80211_queue_work(&sdata->local->hw,
 					     &sdata->u.mgd.monitor_work);
-		/* and do all the other regular work too */
-		ieee80211_queue_work(&sdata->local->hw, &sdata->work);
 	}
 }
 
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 96c3e3d5ef70..26f9f77a94bf 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -276,6 +276,7 @@ static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
 	struct ieee80211_local *local = hw_to_local(hw);
 	bool hw_scan = local->ops->hw_scan;
 	bool was_scanning = local->scanning;
+	struct ieee80211_sub_if_data *sdata;
 
 	lockdep_assert_held(&local->mtx);
 
@@ -327,7 +328,16 @@ static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
 
 	ieee80211_mlme_notify_scan_completed(local);
 	ieee80211_ibss_notify_scan_completed(local);
-	ieee80211_mesh_notify_scan_completed(local);
+
+	/* Requeue all the work that might have been ignored while
+	 * the scan was in progress; if there was none this will
+	 * just be a no-op for the particular interface.
+	 */
+	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+		if (ieee80211_sdata_running(sdata))
+			ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+	}
+
 	if (was_scanning)
 		ieee80211_start_next_roc(local);
 }