xfs: convert unwritten status of reverse mappings for shared files

Provide a function to convert an unwritten extent to a real one and
vice versa when shared extents are possible.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/xfs/xfs_rmap_item.c

@@ -496,6 +496,9 @@ xfs_rui_recover(
 		case XFS_RMAP_EXTENT_CONVERT:
 			type = XFS_RMAP_CONVERT;
 			break;
+		case XFS_RMAP_EXTENT_CONVERT_SHARED:
+			type = XFS_RMAP_CONVERT_SHARED;
+			break;
 		case XFS_RMAP_EXTENT_ALLOC:
 			type = XFS_RMAP_ALLOC;
 			break;