diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 89be36a0fed62b69068236db2fb0cef166890784..00baa806662a03dbe3a34e72c66561369027c0f8 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1249,7 +1249,6 @@ int btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
 
 void btrfs_release_disk_super(struct page *page)
 {
-	kunmap(page);
 	put_page(page);
 }
 
@@ -1277,10 +1276,10 @@ static int btrfs_read_disk_super(struct block_device *bdev, u64 bytenr,
 	*page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
 				   index, GFP_KERNEL);
 
-	if (IS_ERR_OR_NULL(*page))
+	if (IS_ERR(*page))
 		return 1;
 
-	p = kmap(*page);
+	p = page_address(*page);
 
 	/* align our pointer to the offset of the super block */
 	*disk_super = p + offset_in_page(bytenr);