1 files changed, 43 insertions, 69 deletions

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 5e9d3bc6a2d9..a6701ed87f0d 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -533,10 +533,11 @@ static inline u16 seq_sub(u16 sq1, u16 sq2)
 
 static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
 					    struct tid_ampdu_rx *tid_agg_rx,
-					    int index,
-					    struct sk_buff_head *frames)
+					    int index)
 {
+	struct ieee80211_local *local = hw_to_local(hw);
 	struct sk_buff *skb = tid_agg_rx->reorder_buf[index];
+	struct ieee80211_rx_status *status;
 
 	lockdep_assert_held(&tid_agg_rx->reorder_lock);
 
@@ -546,7 +547,9 @@ static void ieee80211_release_reorder_frame(struct ieee80211_hw *hw,
 	/* release the frame from the reorder ring buffer */
 	tid_agg_rx->stored_mpdu_num--;
 	tid_agg_rx->reorder_buf[index] = NULL;
-	__skb_queue_tail(frames, skb);
+	status = IEEE80211_SKB_RXCB(skb);
+	status->rx_flags |= IEEE80211_RX_DEFERRED_RELEASE;
+	skb_queue_tail(&local->rx_skb_queue, skb);
 
 no_frame:
 	tid_agg_rx->head_seq_num = seq_inc(tid_agg_rx->head_seq_num);
@@ -554,8 +557,7 @@ no_frame:
 
 static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
 					     struct tid_ampdu_rx *tid_agg_rx,
-					     u16 head_seq_num,
-					     struct sk_buff_head *frames)
+					     u16 head_seq_num)
 {
 	int index;
 
@@ -564,7 +566,7 @@ static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
 	while (seq_less(tid_agg_rx->head_seq_num, head_seq_num)) {
 		index = seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 							tid_agg_rx->buf_size;
-		ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
+		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
 	}
 }
 
@@ -580,8 +582,7 @@ static void ieee80211_release_reorder_frames(struct ieee80211_hw *hw,
 #define HT_RX_REORDER_BUF_TIMEOUT (HZ / 10)
 
 static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
-					  struct tid_ampdu_rx *tid_agg_rx,
-					  struct sk_buff_head *frames)
+					  struct tid_ampdu_rx *tid_agg_rx)
 {
 	int index, j;
 
@@ -612,8 +613,7 @@ static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
 				wiphy_debug(hw->wiphy,
 					    "release an RX reorder frame due to timeout on earlier frames\n");
 #endif
-			ieee80211_release_reorder_frame(hw, tid_agg_rx,
-							j, frames);
+			ieee80211_release_reorder_frame(hw, tid_agg_rx, j);
 
 			/*
 			 * Increment the head seq# also for the skipped slots.
@@ -623,31 +623,11 @@ static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
 			skipped = 0;
 		}
 	} else while (tid_agg_rx->reorder_buf[index]) {
-		ieee80211_release_reorder_frame(hw, tid_agg_rx, index, frames);
+		ieee80211_release_reorder_frame(hw, tid_agg_rx, index);
 		index =	seq_sub(tid_agg_rx->head_seq_num, tid_agg_rx->ssn) %
 							tid_agg_rx->buf_size;
 	}
 
-	/*
-	 * Disable the reorder release timer for now.
-	 *
-	 * The current implementation lacks a proper locking scheme
-	 * which would protect vital statistic and debug counters
-	 * from being updated by two different but concurrent BHs.
-	 *
-	 * More information about the topic is available from:
-	 * - thread: http://marc.info/?t=128635927000001
-	 *
-	 * What was wrong:
-	 * =>  http://marc.info/?l=linux-wireless&m=128636170811964
-	 * "Basically the thing is that until your patch, the data
-	 *  in the struct didn't actually need locking because it
-	 *  was accessed by the RX path only which is not concurrent."
-	 *
-	 * List of what needs to be fixed:
-	 * => http://marc.info/?l=linux-wireless&m=128656352920957
-	 *
-
 	if (tid_agg_rx->stored_mpdu_num) {
 		j = index = seq_sub(tid_agg_rx->head_seq_num,
 				    tid_agg_rx->ssn) % tid_agg_rx->buf_size;
@@ -666,10 +646,6 @@ static void ieee80211_sta_reorder_release(struct ieee80211_hw *hw,
 	} else {
 		del_timer(&tid_agg_rx->reorder_timer);
 	}
-	*/
-
-set_release_timer:
-	return;
 }
 
 /*
@@ -679,8 +655,7 @@ set_release_timer:
  */
 static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
 					     struct tid_ampdu_rx *tid_agg_rx,
-					     struct sk_buff *skb,
-					     struct sk_buff_head *frames)
+					     struct sk_buff *skb)
 {
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 	u16 sc = le16_to_cpu(hdr->seq_ctrl);
@@ -707,8 +682,7 @@ static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
 	if (!seq_less(mpdu_seq_num, head_seq_num + buf_size)) {
 		head_seq_num = seq_inc(seq_sub(mpdu_seq_num, buf_size));
 		/* release stored frames up to new head to stack */
-		ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num,
-						 frames);
+		ieee80211_release_reorder_frames(hw, tid_agg_rx, head_seq_num);
 	}
 
 	/* Now the new frame is always in the range of the reordering buffer */
@@ -736,7 +710,7 @@ static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
 	tid_agg_rx->reorder_buf[index] = skb;
 	tid_agg_rx->reorder_time[index] = jiffies;
 	tid_agg_rx->stored_mpdu_num++;
-	ieee80211_sta_reorder_release(hw, tid_agg_rx, frames);
+	ieee80211_sta_reorder_release(hw, tid_agg_rx);
 
  out:
 	spin_unlock(&tid_agg_rx->reorder_lock);
@@ -747,8 +721,7 @@ static bool ieee80211_sta_manage_reorder_buf(struct ieee80211_hw *hw,
  * Reorder MPDUs from A-MPDUs, keeping them on a buffer. Returns
  * true if the MPDU was buffered, false if it should be processed.
  */
-static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
-				       struct sk_buff_head *frames)
+static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx)
 {
 	struct sk_buff *skb = rx->skb;
 	struct ieee80211_local *local = rx->local;
@@ -803,11 +776,11 @@ static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
 	 * sure that we cannot get to it any more before doing
 	 * anything with it.
 	 */
-	if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb, frames))
+	if (ieee80211_sta_manage_reorder_buf(hw, tid_agg_rx, skb))
 		return;
 
  dont_reorder:
-	__skb_queue_tail(frames, skb);
+	skb_queue_tail(&local->rx_skb_queue, skb);
 }
 
 static ieee80211_rx_result debug_noinline
@@ -1189,6 +1162,7 @@ ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
 	 * exchange sequence.
 	 */
 	if (!ieee80211_has_morefrags(hdr->frame_control) &&
+	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN)) {
 		if (test_sta_flags(sta, WLAN_STA_PS_STA)) {
@@ -1831,11 +1805,11 @@ ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
 
 			fwd_skb = skb_copy(skb, GFP_ATOMIC);
 
-			if (!fwd_skb && net_ratelimit()) {
+			if (!fwd_skb && net_ratelimit())
 				printk(KERN_DEBUG "%s: failed to clone mesh frame\n",
 						   sdata->name);
+			if (!fwd_skb)
 				goto out;
-			}
 
 			fwd_hdr =  (struct ieee80211_hdr *) fwd_skb->data;
 			memcpy(fwd_hdr->addr2, sdata->vif.addr, ETH_ALEN);
@@ -1930,7 +1904,7 @@ ieee80211_rx_h_data(struct ieee80211_rx_data *rx)
 }
 
 static ieee80211_rx_result debug_noinline
-ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
+ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx)
 {
 	struct ieee80211_local *local = rx->local;
 	struct ieee80211_hw *hw = &local->hw;
@@ -1970,8 +1944,7 @@ ieee80211_rx_h_ctrl(struct ieee80211_rx_data *rx, struct sk_buff_head *frames)
 
 		spin_lock(&tid_agg_rx->reorder_lock);
 		/* release stored frames up to start of BAR */
-		ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num,
-						 frames);
+		ieee80211_release_reorder_frames(hw, tid_agg_rx, start_seq_num);
 		spin_unlock(&tid_agg_rx->reorder_lock);
 
 		kfree_skb(skb);
@@ -2488,8 +2461,7 @@ static void ieee80211_rx_handlers_result(struct ieee80211_rx_data *rx,
 	}
 }
 
-static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
-				  struct sk_buff_head *frames)
+static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx)
 {
 	ieee80211_rx_result res = RX_DROP_MONITOR;
 	struct sk_buff *skb;
@@ -2501,7 +2473,15 @@ static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
 			goto rxh_next;  \
 	} while (0);
 
-	while ((skb = __skb_dequeue(frames))) {
+	spin_lock(&rx->local->rx_skb_queue.lock);
+	if (rx->local->running_rx_handler)
+		goto unlock;
+
+	rx->local->running_rx_handler = true;
+
+	while ((skb = __skb_dequeue(&rx->local->rx_skb_queue))) {
+		spin_unlock(&rx->local->rx_skb_queue.lock);
+
 		/*
 		 * all the other fields are valid across frames
 		 * that belong to an aMPDU since they are on the
@@ -2524,12 +2504,7 @@ static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
 			CALL_RXH(ieee80211_rx_h_mesh_fwding);
 #endif
 		CALL_RXH(ieee80211_rx_h_data)
-
-		/* special treatment -- needs the queue */
-		res = ieee80211_rx_h_ctrl(rx, frames);
-		if (res != RX_CONTINUE)
-			goto rxh_next;
-
+		CALL_RXH(ieee80211_rx_h_ctrl);
 		CALL_RXH(ieee80211_rx_h_mgmt_check)
 		CALL_RXH(ieee80211_rx_h_action)
 		CALL_RXH(ieee80211_rx_h_userspace_mgmt)
@@ -2538,18 +2513,20 @@ static void ieee80211_rx_handlers(struct ieee80211_rx_data *rx,
 
  rxh_next:
 		ieee80211_rx_handlers_result(rx, res);
-
+		spin_lock(&rx->local->rx_skb_queue.lock);
 #undef CALL_RXH
 	}
+
+	rx->local->running_rx_handler = false;
+
+ unlock:
+	spin_unlock(&rx->local->rx_skb_queue.lock);
 }
 
 static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
 {
-	struct sk_buff_head reorder_release;
 	ieee80211_rx_result res = RX_DROP_MONITOR;
 
-	__skb_queue_head_init(&reorder_release);
-
 #define CALL_RXH(rxh)			\
 	do {				\
 		res = rxh(rx);		\
@@ -2560,9 +2537,9 @@ static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
 	CALL_RXH(ieee80211_rx_h_passive_scan)
 	CALL_RXH(ieee80211_rx_h_check)
 
-	ieee80211_rx_reorder_ampdu(rx, &reorder_release);
+	ieee80211_rx_reorder_ampdu(rx);
 
-	ieee80211_rx_handlers(rx, &reorder_release);
+	ieee80211_rx_handlers(rx);
 	return;
 
  rxh_next:
@@ -2577,7 +2554,6 @@ static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
  */
 void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
 {
-	struct sk_buff_head frames;
 	struct ieee80211_rx_data rx = {
 		.sta = sta,
 		.sdata = sta->sdata,
@@ -2590,13 +2566,11 @@ void ieee80211_release_reorder_timeout(struct sta_info *sta, int tid)
 	if (!tid_agg_rx)
 		return;
 
-	__skb_queue_head_init(&frames);
-
 	spin_lock(&tid_agg_rx->reorder_lock);
-	ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx, &frames);
+	ieee80211_sta_reorder_release(&sta->local->hw, tid_agg_rx);
 	spin_unlock(&tid_agg_rx->reorder_lock);
 
-	ieee80211_rx_handlers(&rx, &frames);
+	ieee80211_rx_handlers(&rx);
 }
 
 /* main receive path */