iwlwifi: clear driver stations when going down

During a hw restart, mac80211 will attempt to
reconfigure all stations. Currently, that fails
and leads to warnings because we still have the
stations marked active. Therefore, clear all
stations when doing down.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>

drivers/net/wireless/iwlwifi/iwl-agn.c

@@ -2405,6 +2405,7 @@ static void __iwl_down(struct iwl_priv *priv)
 
 	iwl_clear_ucode_stations(priv);
 	iwl_dealloc_bcast_station(priv);
+	iwl_clear_driver_stations(priv);
 
 	/* Unblock any waiting calls */
 	wake_up_interruptible_all(&priv->wait_command_queue);

drivers/net/wireless/iwlwifi/iwl-sta.h

@@ -81,6 +81,25 @@ int iwl_sta_rx_agg_stop(struct iwl_priv *priv, struct ieee80211_sta *sta,
 void iwl_sta_modify_ps_wake(struct iwl_priv *priv, int sta_id);
 void iwl_sta_modify_sleep_tx_count(struct iwl_priv *priv, int sta_id, int cnt);
 
+/**
+ * iwl_clear_driver_stations - clear knowledge of all stations from driver
+ * @priv: iwl priv struct
+ *
+ * This is called during iwl_down() to make sure that in the case
+ * we're coming there from a hardware restart mac80211 will be
+ * able to reconfigure stations -- if we're getting there in the
+ * normal down flow then the stations will already be cleared.
+ */
+static inline void iwl_clear_driver_stations(struct iwl_priv *priv)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv->sta_lock, flags);
+	memset(priv->stations, 0, sizeof(priv->stations));
+	priv->num_stations = 0;
+	spin_unlock_irqrestore(&priv->sta_lock, flags);
+}
+
 static inline int iwl_sta_id(struct ieee80211_sta *sta)
 {
 	if (WARN_ON(!sta))

drivers/net/wireless/iwlwifi/iwl3945-base.c

@@ -2585,6 +2585,7 @@ static void __iwl3945_down(struct iwl_priv *priv)
 	/* Station information will now be cleared in device */
 	iwl_clear_ucode_stations(priv);
 	iwl_dealloc_bcast_station(priv);
+	iwl_clear_driver_stations(priv);
 
 	/* Unblock any waiting calls */
 	wake_up_interruptible_all(&priv->wait_command_queue);