1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 /* 3 * This file describes the layout of the file handles as passed 4 * over the wire. 5 * 6 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de> 7 */ 8 9 #ifndef _UAPI_LINUX_NFSD_FH_H 10 #define _UAPI_LINUX_NFSD_FH_H 11 12 #include <linux/types.h> 13 #include <linux/nfs.h> 14 #include <linux/nfs2.h> 15 #include <linux/nfs3.h> 16 #include <linux/nfs4.h> 17 18 /* 19 * This is the old "dentry style" Linux NFSv2 file handle. 20 * 21 * The xino and xdev fields are currently used to transport the 22 * ino/dev of the exported inode. 23 */ 24 struct nfs_fhbase_old { 25 __u32 fb_dcookie; /* dentry cookie - always 0xfeebbaca */ 26 __u32 fb_ino; /* our inode number */ 27 __u32 fb_dirino; /* dir inode number, 0 for directories */ 28 __u32 fb_dev; /* our device */ 29 __u32 fb_xdev; 30 __u32 fb_xino; 31 __u32 fb_generation; 32 }; 33 34 /* 35 * This is the new flexible, extensible style NFSv2/v3/v4 file handle. 36 * by Neil Brown <neilb@cse.unsw.edu.au> - March 2000 37 * 38 * The file handle starts with a sequence of four-byte words. 39 * The first word contains a version number (1) and three descriptor bytes 40 * that tell how the remaining 3 variable length fields should be handled. 41 * These three bytes are auth_type, fsid_type and fileid_type. 42 * 43 * All four-byte values are in host-byte-order. 44 * 45 * The auth_type field is deprecated and must be set to 0. 46 * 47 * The fsid_type identifies how the filesystem (or export point) is 48 * encoded. 49 * Current values: 50 * 0 - 4 byte device id (ms-2-bytes major, ls-2-bytes minor), 4byte inode number 51 * NOTE: we cannot use the kdev_t device id value, because kdev_t.h 52 * says we mustn't. We must break it up and reassemble. 53 * 1 - 4 byte user specified identifier 54 * 2 - 4 byte major, 4 byte minor, 4 byte inode number - DEPRECATED 55 * 3 - 4 byte device id, encoded for user-space, 4 byte inode number 56 * 4 - 4 byte inode number and 4 byte uuid 57 * 5 - 8 byte uuid 58 * 6 - 16 byte uuid 59 * 7 - 8 byte inode number and 16 byte uuid 60 * 61 * The fileid_type identified how the file within the filesystem is encoded. 62 * The values for this field are filesystem specific, exccept that 63 * filesystems must not use the values '0' or '0xff'. 'See enum fid_type' 64 * in include/linux/exportfs.h for currently registered values. 65 */ 66 struct nfs_fhbase_new { 67 __u8 fb_version; /* == 1, even => nfs_fhbase_old */ 68 __u8 fb_auth_type; 69 __u8 fb_fsid_type; 70 __u8 fb_fileid_type; 71 __u32 fb_auth[1]; 72 /* __u32 fb_fsid[0]; floating */ 73 /* __u32 fb_fileid[0]; floating */ 74 }; 75 76 struct knfsd_fh { 77 unsigned int fh_size; /* significant for NFSv3. 78 * Points to the current size while building 79 * a new file handle 80 */ 81 union { 82 struct nfs_fhbase_old fh_old; 83 __u32 fh_pad[NFS4_FHSIZE/4]; 84 struct nfs_fhbase_new fh_new; 85 } fh_base; 86 }; 87 88 #define ofh_dcookie fh_base.fh_old.fb_dcookie 89 #define ofh_ino fh_base.fh_old.fb_ino 90 #define ofh_dirino fh_base.fh_old.fb_dirino 91 #define ofh_dev fh_base.fh_old.fb_dev 92 #define ofh_xdev fh_base.fh_old.fb_xdev 93 #define ofh_xino fh_base.fh_old.fb_xino 94 #define ofh_generation fh_base.fh_old.fb_generation 95 96 #define fh_version fh_base.fh_new.fb_version 97 #define fh_fsid_type fh_base.fh_new.fb_fsid_type 98 #define fh_auth_type fh_base.fh_new.fb_auth_type 99 #define fh_fileid_type fh_base.fh_new.fb_fileid_type 100 #define fh_fsid fh_base.fh_new.fb_auth 101 102 /* Do not use, provided for userspace compatiblity. */ 103 #define fh_auth fh_base.fh_new.fb_auth 104 105 #endif /* _UAPI_LINUX_NFSD_FH_H */ 106