1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2005 Silicon Graphics, Inc.
4 * All Rights Reserved.
5 */
6#ifndef __XFS_EXPORT_H__
7#define __XFS_EXPORT_H__
8
9/*
10 * Common defines for code related to exporting XFS filesystems over NFS.
11 *
12 * The NFS fileid goes out on the wire as an array of
13 * 32bit unsigned ints in host order.  There are 5 possible
14 * formats.
15 *
16 * (1)	fileid_type=0x00
17 *	(no fileid data; handled by the generic code)
18 *
19 * (2)	fileid_type=0x01
20 *	inode-num
21 *	generation
22 *
23 * (3)	fileid_type=0x02
24 *	inode-num
25 *	generation
26 *	parent-inode-num
27 *	parent-generation
28 *
29 * (4)	fileid_type=0x81
30 *	inode-num-lo32
31 *	inode-num-hi32
32 *	generation
33 *
34 * (5)	fileid_type=0x82
35 *	inode-num-lo32
36 *	inode-num-hi32
37 *	generation
38 *	parent-inode-num-lo32
39 *	parent-inode-num-hi32
40 *	parent-generation
41 *
42 * Note, the NFS filehandle also includes an fsid portion which
43 * may have an inode number in it.  That number is hardcoded to
44 * 32bits and there is no way for XFS to intercept it.  In
45 * practice this means when exporting an XFS filesystem with 64bit
46 * inodes you should either export the mountpoint (rather than
47 * a subdirectory) or use the "fsid" export option.
48 */
49
50struct xfs_fid64 {
51	u64 ino;
52	u32 gen;
53	u64 parent_ino;
54	u32 parent_gen;
55} __attribute__((packed));
56
57/* This flag goes on the wire.  Don't play with it. */
58#define XFS_FILEID_TYPE_64FLAG	0x80	/* NFS fileid has 64bit inodes */
59
60#endif	/* __XFS_EXPORT_H__ */
61