xfs: move ftype conversion functions to libxfs

These functions are needed in userspace for repair and mkfs to
do the right thing. Move them to libxfs so they can be easily
shared.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>

fs/xfs/libxfs/xfs_dir2.c

@@ -38,6 +38,22 @@
 
 struct xfs_name xfs_name_dotdot = { (unsigned char *)"..", 2, XFS_DIR3_FT_DIR };
 
+/*
+ * @mode, if set, indicates that the type field needs to be set up.
+ * This uses the transformation from file mode to DT_* as defined in linux/fs.h
+ * for file type specification. This will be propagated into the directory
+ * structure if appropriate for the given operation and filesystem config.
+ */
+const unsigned char xfs_mode_to_ftype[S_IFMT >> S_SHIFT] = {
+	[0]			= XFS_DIR3_FT_UNKNOWN,
+	[S_IFREG >> S_SHIFT]    = XFS_DIR3_FT_REG_FILE,
+	[S_IFDIR >> S_SHIFT]    = XFS_DIR3_FT_DIR,
+	[S_IFCHR >> S_SHIFT]    = XFS_DIR3_FT_CHRDEV,
+	[S_IFBLK >> S_SHIFT]    = XFS_DIR3_FT_BLKDEV,
+	[S_IFIFO >> S_SHIFT]    = XFS_DIR3_FT_FIFO,
+	[S_IFSOCK >> S_SHIFT]   = XFS_DIR3_FT_SOCK,
+	[S_IFLNK >> S_SHIFT]    = XFS_DIR3_FT_SYMLINK,
+};
 
 /*
  * ASCII case-insensitive (ie. A-Z) support for directories that was