---
 drivers/md/dm-thin.c |   17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

Index: linux-3.0/drivers/md/dm-thin.c
===================================================================
--- linux-3.0.orig/drivers/md/dm-thin.c
+++ linux-3.0/drivers/md/dm-thin.c
@@ -487,6 +487,8 @@ struct pool {
 	mempool_t *endio_hook_pool;
 
 	atomic_t ref_count;
+
+	struct mutex big_lock;
 };
 
 /*
@@ -1126,14 +1128,18 @@ static void do_producer(struct work_stru
 {
 	struct pool *pool = container_of(ws, struct pool, producer);
 
+	mutex_lock(&pool->big_lock);
 	process_deferred_bios(pool);
+	mutex_unlock(&pool->big_lock);
 }
 
 static void do_consumer(struct work_struct *ws)
 {
 	struct pool *pool = container_of(ws, struct pool, consumer);
 
+	mutex_lock(&pool->big_lock);
 	process_prepared_mappings(pool);
+	mutex_unlock(&pool->big_lock);
 }
 
 static void defer_bio(struct thin_c *tc, struct bio *bio)
@@ -1396,6 +1402,7 @@ static struct pool *pool_create(struct b
 	}
 	atomic_set(&pool->ref_count, 1);
 
+	mutex_init(&pool->big_lock);
 	return pool;
 
 bad_endio_hook_pool:
@@ -2123,9 +2130,17 @@ bad_pool_dev:
 static int thin_map(struct dm_target *ti, struct bio *bio,
 		    union map_info *map_context)
 {
+	int r;
+	struct thin_c *tc = ti->private;
+	struct pool *pool = tc->pool;
+
 	bio->bi_sector -= ti->begin;
 
-	return bio_map(ti, bio, map_context);
+	mutex_lock(&pool->big_lock);
+	r = bio_map(ti, bio, map_context);
+	mutex_unlock(&pool->big_lock);
+
+	return r;
 }
 
 /*