diff --git a/fs/buffer.c b/fs/buffer.c
index 1d3683d..0d6ca7b 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -201,7 +201,7 @@
  * freeze_bdev  --  lock a filesystem and force it into a consistent state
  * @bdev:	blockdevice to lock
  *
- * This takes the block device bd_mount_sem to make sure no new mounts
+ * This takes the block device bd_mount_mutex to make sure no new mounts
  * happen on bdev until thaw_bdev() is called.
  * If a superblock is found on this device, we take the s_umount semaphore
  * on it to make sure nobody unmounts until the snapshot creation is done.
@@ -210,7 +210,7 @@
 {
 	struct super_block *sb;
 
-	down(&bdev->bd_mount_sem);
+	mutex_lock(&bdev->bd_mount_mutex);
 	sb = get_super(bdev);
 	if (sb && !(sb->s_flags & MS_RDONLY)) {
 		sb->s_frozen = SB_FREEZE_WRITE;
@@ -264,7 +264,7 @@
 		drop_super(sb);
 	}
 
-	up(&bdev->bd_mount_sem);
+	mutex_unlock(&bdev->bd_mount_mutex);
 }
 EXPORT_SYMBOL(thaw_bdev);