mac80211: Fix a race on enabling power save.

Commit Message

Vivek Natarajan Feb. 23, 2011, 7:34 a.m. UTC

None

Patch

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 7b3f9df..abb0116 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -738,9 +738,19 @@  void ieee80211_dynamic_ps_enable_work(struct work_struct *work)
 		return;
 
 	if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) &&
-	    (!(ifmgd->flags & IEEE80211_STA_NULLFUNC_ACKED)))
+	    (!(ifmgd->flags & IEEE80211_STA_NULLFUNC_ACKED))) {
+		netif_tx_stop_all_queues(sdata->dev);
+		/*
+		 * Flush all the frames queued in the driver before
+		 * going to power save
+		 */
+		drv_flush(local, false);
 		ieee80211_send_nullfunc(local, sdata, 1);
 
+		/* Flush once again to get the tx status of nullfunc frame */
+		drv_flush(local, false);
+	}
+
 	if (!((local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) &&
 	      (local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)) ||
 	    (ifmgd->flags & IEEE80211_STA_NULLFUNC_ACKED)) {
@@ -748,6 +758,8 @@  void ieee80211_dynamic_ps_enable_work(struct work_struct *work)
 		local->hw.conf.flags |= IEEE80211_CONF_PS;
 		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
 	}
+
+	netif_tx_start_all_queues(sdata->dev);
 }
 
 void ieee80211_dynamic_ps_timer(unsigned long data)
diff --git a/net/mac80211/status.c b/net/mac80211/status.c
index 010a559..8651851 100644
--- a/net/mac80211/status.c
+++ b/net/mac80211/status.c
@@ -318,8 +318,6 @@  void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
 		if (info->flags & IEEE80211_TX_STAT_ACK) {
 			local->ps_sdata->u.mgd.flags |=
 					IEEE80211_STA_NULLFUNC_ACKED;
-			ieee80211_queue_work(&local->hw,
-					&local->dynamic_ps_enable_work);
 		} else
 			mod_timer(&local->dynamic_ps_timer, jiffies +
 					msecs_to_jiffies(10));