From 83be4ac327978b0b921d4bccc647739a3b1a146a Mon Sep 17 00:00:00 2001
From: Chandra Seetharaman <sekharan@us.ibm.com>
Date: Thu, 13 Nov 2008 23:39:14 +0000
Subject: [PATCH] --- yaml --- r: 118957 b: refs/heads/master c:
 8a57dfc6f943c92b861c9a19b0c86ddcb2aba768 h: refs/heads/master i:   118955:
 86b4566b4bb0a199de96b7f8985c342d583c2460 v: v3

---
 [refs]                |  2 +-
 trunk/drivers/md/dm.c | 24 ++++++++++++++++--------
 2 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/[refs] b/[refs]
index e0236f1bbb32..6ab971350c6b 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d221d2e77696e70e94b13989ea15db2ba5b34f8e
+refs/heads/master: 8a57dfc6f943c92b861c9a19b0c86ddcb2aba768
diff --git a/trunk/drivers/md/dm.c b/trunk/drivers/md/dm.c
index dc25d8a07bc7..c99e4728ff41 100644
--- a/trunk/drivers/md/dm.c
+++ b/trunk/drivers/md/dm.c
@@ -937,16 +937,24 @@ static void dm_unplug_all(struct request_queue *q)
 
 static int dm_any_congested(void *congested_data, int bdi_bits)
 {
-	int r;
-	struct mapped_device *md = (struct mapped_device *) congested_data;
-	struct dm_table *map = dm_get_table(md);
+	int r = bdi_bits;
+	struct mapped_device *md = congested_data;
+	struct dm_table *map;
 
-	if (!map || test_bit(DMF_BLOCK_IO, &md->flags))
-		r = bdi_bits;
-	else
-		r = dm_table_any_congested(map, bdi_bits);
+	atomic_inc(&md->pending);
+
+	if (!test_bit(DMF_BLOCK_IO, &md->flags)) {
+		map = dm_get_table(md);
+		if (map) {
+			r = dm_table_any_congested(map, bdi_bits);
+			dm_table_put(map);
+		}
+	}
+
+	if (!atomic_dec_return(&md->pending))
+		/* nudge anyone waiting on suspend queue */
+		wake_up(&md->wait);
 
-	dm_table_put(map);
 	return r;
 }