xref: /OK3568_Linux_fs/kernel/include/uapi/linux/nfsd/nfsfh.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * This file describes the layout of the file handles as passed
4*4882a593Smuzhiyun  * over the wire.
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
7*4882a593Smuzhiyun  */
8*4882a593Smuzhiyun 
9*4882a593Smuzhiyun #ifndef _UAPI_LINUX_NFSD_FH_H
10*4882a593Smuzhiyun #define _UAPI_LINUX_NFSD_FH_H
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun #include <linux/types.h>
13*4882a593Smuzhiyun #include <linux/nfs.h>
14*4882a593Smuzhiyun #include <linux/nfs2.h>
15*4882a593Smuzhiyun #include <linux/nfs3.h>
16*4882a593Smuzhiyun #include <linux/nfs4.h>
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun /*
19*4882a593Smuzhiyun  * This is the old "dentry style" Linux NFSv2 file handle.
20*4882a593Smuzhiyun  *
21*4882a593Smuzhiyun  * The xino and xdev fields are currently used to transport the
22*4882a593Smuzhiyun  * ino/dev of the exported inode.
23*4882a593Smuzhiyun  */
24*4882a593Smuzhiyun struct nfs_fhbase_old {
25*4882a593Smuzhiyun 	__u32		fb_dcookie;	/* dentry cookie - always 0xfeebbaca */
26*4882a593Smuzhiyun 	__u32		fb_ino;		/* our inode number */
27*4882a593Smuzhiyun 	__u32		fb_dirino;	/* dir inode number, 0 for directories */
28*4882a593Smuzhiyun 	__u32		fb_dev;		/* our device */
29*4882a593Smuzhiyun 	__u32		fb_xdev;
30*4882a593Smuzhiyun 	__u32		fb_xino;
31*4882a593Smuzhiyun 	__u32		fb_generation;
32*4882a593Smuzhiyun };
33*4882a593Smuzhiyun 
34*4882a593Smuzhiyun /*
35*4882a593Smuzhiyun  * This is the new flexible, extensible style NFSv2/v3/v4 file handle.
36*4882a593Smuzhiyun  * by Neil Brown <neilb@cse.unsw.edu.au> - March 2000
37*4882a593Smuzhiyun  *
38*4882a593Smuzhiyun  * The file handle starts with a sequence of four-byte words.
39*4882a593Smuzhiyun  * The first word contains a version number (1) and three descriptor bytes
40*4882a593Smuzhiyun  * that tell how the remaining 3 variable length fields should be handled.
41*4882a593Smuzhiyun  * These three bytes are auth_type, fsid_type and fileid_type.
42*4882a593Smuzhiyun  *
43*4882a593Smuzhiyun  * All four-byte values are in host-byte-order.
44*4882a593Smuzhiyun  *
45*4882a593Smuzhiyun  * The auth_type field is deprecated and must be set to 0.
46*4882a593Smuzhiyun  *
47*4882a593Smuzhiyun  * The fsid_type identifies how the filesystem (or export point) is
48*4882a593Smuzhiyun  *    encoded.
49*4882a593Smuzhiyun  *  Current values:
50*4882a593Smuzhiyun  *     0  - 4 byte device id (ms-2-bytes major, ls-2-bytes minor), 4byte inode number
51*4882a593Smuzhiyun  *        NOTE: we cannot use the kdev_t device id value, because kdev_t.h
52*4882a593Smuzhiyun  *              says we mustn't.  We must break it up and reassemble.
53*4882a593Smuzhiyun  *     1  - 4 byte user specified identifier
54*4882a593Smuzhiyun  *     2  - 4 byte major, 4 byte minor, 4 byte inode number - DEPRECATED
55*4882a593Smuzhiyun  *     3  - 4 byte device id, encoded for user-space, 4 byte inode number
56*4882a593Smuzhiyun  *     4  - 4 byte inode number and 4 byte uuid
57*4882a593Smuzhiyun  *     5  - 8 byte uuid
58*4882a593Smuzhiyun  *     6  - 16 byte uuid
59*4882a593Smuzhiyun  *     7  - 8 byte inode number and 16 byte uuid
60*4882a593Smuzhiyun  *
61*4882a593Smuzhiyun  * The fileid_type identified how the file within the filesystem is encoded.
62*4882a593Smuzhiyun  *   The values for this field are filesystem specific, exccept that
63*4882a593Smuzhiyun  *   filesystems must not use the values '0' or '0xff'. 'See enum fid_type'
64*4882a593Smuzhiyun  *   in include/linux/exportfs.h for currently registered values.
65*4882a593Smuzhiyun  */
66*4882a593Smuzhiyun struct nfs_fhbase_new {
67*4882a593Smuzhiyun 	__u8		fb_version;	/* == 1, even => nfs_fhbase_old */
68*4882a593Smuzhiyun 	__u8		fb_auth_type;
69*4882a593Smuzhiyun 	__u8		fb_fsid_type;
70*4882a593Smuzhiyun 	__u8		fb_fileid_type;
71*4882a593Smuzhiyun 	__u32		fb_auth[1];
72*4882a593Smuzhiyun /*	__u32		fb_fsid[0]; floating */
73*4882a593Smuzhiyun /*	__u32		fb_fileid[0]; floating */
74*4882a593Smuzhiyun };
75*4882a593Smuzhiyun 
76*4882a593Smuzhiyun struct knfsd_fh {
77*4882a593Smuzhiyun 	unsigned int	fh_size;	/* significant for NFSv3.
78*4882a593Smuzhiyun 					 * Points to the current size while building
79*4882a593Smuzhiyun 					 * a new file handle
80*4882a593Smuzhiyun 					 */
81*4882a593Smuzhiyun 	union {
82*4882a593Smuzhiyun 		struct nfs_fhbase_old	fh_old;
83*4882a593Smuzhiyun 		__u32			fh_pad[NFS4_FHSIZE/4];
84*4882a593Smuzhiyun 		struct nfs_fhbase_new	fh_new;
85*4882a593Smuzhiyun 	} fh_base;
86*4882a593Smuzhiyun };
87*4882a593Smuzhiyun 
88*4882a593Smuzhiyun #define ofh_dcookie		fh_base.fh_old.fb_dcookie
89*4882a593Smuzhiyun #define ofh_ino			fh_base.fh_old.fb_ino
90*4882a593Smuzhiyun #define ofh_dirino		fh_base.fh_old.fb_dirino
91*4882a593Smuzhiyun #define ofh_dev			fh_base.fh_old.fb_dev
92*4882a593Smuzhiyun #define ofh_xdev		fh_base.fh_old.fb_xdev
93*4882a593Smuzhiyun #define ofh_xino		fh_base.fh_old.fb_xino
94*4882a593Smuzhiyun #define ofh_generation		fh_base.fh_old.fb_generation
95*4882a593Smuzhiyun 
96*4882a593Smuzhiyun #define	fh_version		fh_base.fh_new.fb_version
97*4882a593Smuzhiyun #define	fh_fsid_type		fh_base.fh_new.fb_fsid_type
98*4882a593Smuzhiyun #define	fh_auth_type		fh_base.fh_new.fb_auth_type
99*4882a593Smuzhiyun #define	fh_fileid_type		fh_base.fh_new.fb_fileid_type
100*4882a593Smuzhiyun #define	fh_fsid			fh_base.fh_new.fb_auth
101*4882a593Smuzhiyun 
102*4882a593Smuzhiyun /* Do not use, provided for userspace compatiblity. */
103*4882a593Smuzhiyun #define	fh_auth			fh_base.fh_new.fb_auth
104*4882a593Smuzhiyun 
105*4882a593Smuzhiyun #endif /* _UAPI_LINUX_NFSD_FH_H */
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