4 files changed, 19 insertions, 4 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index b8881750a3ac..3ba4326a63b5 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -562,6 +562,13 @@ static void __blk_drain_queue(struct request_queue *q, bool drain_all)
         }
 }
 
+void blk_drain_queue(struct request_queue *q)
+{
+        spin_lock_irq(q->queue_lock);
+        __blk_drain_queue(q, true);
+        spin_unlock_irq(q->queue_lock);
+}
+
 /**
  * blk_queue_bypass_start - enter queue bypass mode
  * @q: queue of interest
@@ -689,8 +696,6 @@ void blk_cleanup_queue(struct request_queue *q)
          */
         blk_freeze_queue(q);
         spin_lock_irq(lock);
-        if (!q->mq_ops)
-                __blk_drain_queue(q, true);
         queue_flag_set(QUEUE_FLAG_DEAD, q);
         spin_unlock_irq(lock);
 
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 11097477eeab..3d3797327491 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -161,6 +161,8 @@ void blk_freeze_queue(struct request_queue *q)
          * exported to drivers as the only user for unfreeze is blk_mq.
          */
         blk_freeze_queue_start(q);
+        if (!q->mq_ops)
+                blk_drain_queue(q);
         blk_mq_freeze_queue_wait(q);
 }
 
diff --git a/block/blk.h b/block/blk.h
index 3f1446937aec..442098aa9463 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -330,4 +330,6 @@ static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
 }
 #endif /* CONFIG_BOUNCE */
 
+extern void blk_drain_queue(struct request_queue *q);
+
 #endif /* BLK_INTERNAL_H */
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index bc8e61506968..d5fe720cf149 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1581,9 +1581,8 @@ out:
         return err;
 }
 
-static void lo_release(struct gendisk *disk, fmode_t mode)
+static void __lo_release(struct loop_device *lo)
 {
-        struct loop_device *lo = disk->private_data;
         int err;
 
         if (atomic_dec_return(&lo->lo_refcnt))
@@ -1610,6 +1609,13 @@ static void lo_release(struct gendisk *disk, fmode_t mode)
         mutex_unlock(&lo->lo_ctl_mutex);
 }
 
+static void lo_release(struct gendisk *disk, fmode_t mode)
+{
+        mutex_lock(&loop_index_mutex);
+        __lo_release(disk->private_data);
+        mutex_unlock(&loop_index_mutex);
+}
+
 static const struct block_device_operations lo_fops = {
         .owner =        THIS_MODULE,
         .open =         lo_open,