From f3ede2fc13b8a9c5b476b9a4bb382cebe52594f4 Mon Sep 17 00:00:00 2001
From: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Date: Tue, 16 Feb 2010 18:43:01 +0000
Subject: [PATCH] --- yaml --- r: 180583 b: refs/heads/master c:
 9eef87da2a8ea4920e0d913ff977cac064b68ee0 h: refs/heads/master i:   180581:
 a8d99990df64daa52a7ff647471febeeb2300e85   180579:
 441f88bd2f23d902d5b185a5e99c714d627a7403   180575:
 340eded4e3073291ba19b0c2b1d1dbbd121946f3 v: v3

---
 [refs]                |  2 +-
 trunk/drivers/md/dm.c | 21 +++++++++++++++++----
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/[refs] b/[refs]
index 048e3631e3d6..22d33211b024 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 558569aa9d83e016295bac77d900342908d7fd85
+refs/heads/master: 9eef87da2a8ea4920e0d913ff977cac064b68ee0
diff --git a/trunk/drivers/md/dm.c b/trunk/drivers/md/dm.c
index 3167480b532c..aa4e2aa86d49 100644
--- a/trunk/drivers/md/dm.c
+++ b/trunk/drivers/md/dm.c
@@ -1595,10 +1595,15 @@ static int dm_prep_fn(struct request_queue *q, struct request *rq)
 	return BLKPREP_OK;
 }
 
-static void map_request(struct dm_target *ti, struct request *clone,
-			struct mapped_device *md)
+/*
+ * Returns:
+ * 0  : the request has been processed (not requeued)
+ * !0 : the request has been requeued
+ */
+static int map_request(struct dm_target *ti, struct request *clone,
+		       struct mapped_device *md)
 {
-	int r;
+	int r, requeued = 0;
 	struct dm_rq_target_io *tio = clone->end_io_data;
 
 	/*
@@ -1625,6 +1630,7 @@ static void map_request(struct dm_target *ti, struct request *clone,
 	case DM_MAPIO_REQUEUE:
 		/* The target wants to requeue the I/O */
 		dm_requeue_unmapped_request(clone);
+		requeued = 1;
 		break;
 	default:
 		if (r > 0) {
@@ -1636,6 +1642,8 @@ static void map_request(struct dm_target *ti, struct request *clone,
 		dm_kill_unmapped_request(clone, r);
 		break;
 	}
+
+	return requeued;
 }
 
 /*
@@ -1677,12 +1685,17 @@ static void dm_request_fn(struct request_queue *q)
 		atomic_inc(&md->pending[rq_data_dir(clone)]);
 
 		spin_unlock(q->queue_lock);
-		map_request(ti, clone, md);
+		if (map_request(ti, clone, md))
+			goto requeued;
+
 		spin_lock_irq(q->queue_lock);
 	}
 
 	goto out;
 
+requeued:
+	spin_lock_irq(q->queue_lock);
+
 plug_and_out:
 	if (!elv_queue_empty(q))
 		/* Some requests still remain, retry later */