linux/linux-5.18.11/fs/xfs/xfs_export.h

61 lines
1.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#ifndef __XFS_EXPORT_H__
#define __XFS_EXPORT_H__
/*
* Common defines for code related to exporting XFS filesystems over NFS.
*
* The NFS fileid goes out on the wire as an array of
* 32bit unsigned ints in host order. There are 5 possible
* formats.
*
* (1) fileid_type=0x00
* (no fileid data; handled by the generic code)
*
* (2) fileid_type=0x01
* inode-num
* generation
*
* (3) fileid_type=0x02
* inode-num
* generation
* parent-inode-num
* parent-generation
*
* (4) fileid_type=0x81
* inode-num-lo32
* inode-num-hi32
* generation
*
* (5) fileid_type=0x82
* inode-num-lo32
* inode-num-hi32
* generation
* parent-inode-num-lo32
* parent-inode-num-hi32
* parent-generation
*
* Note, the NFS filehandle also includes an fsid portion which
* may have an inode number in it. That number is hardcoded to
* 32bits and there is no way for XFS to intercept it. In
* practice this means when exporting an XFS filesystem with 64bit
* inodes you should either export the mountpoint (rather than
* a subdirectory) or use the "fsid" export option.
*/
struct xfs_fid64 {
u64 ino;
u32 gen;
u64 parent_ino;
u32 parent_gen;
} __attribute__((packed));
/* This flag goes on the wire. Don't play with it. */
#define XFS_FILEID_TYPE_64FLAG 0x80 /* NFS fileid has 64bit inodes */
#endif /* __XFS_EXPORT_H__ */