1 /* 2 * Copyright (c) 2000-2001 Christoph Hellwig. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions, and the following disclaimer, 10 * without modification. 11 * 2. The name of the author may not be used to endorse or promote products 12 * derived from this software without specific prior written permission. 13 * 14 * Alternatively, this software may be distributed under the terms of the 15 * GNU General Public License ("GPL"). 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 21 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 */ 30 #ifndef _VXFS_DIR_H_ 31 #define _VXFS_DIR_H_ 32 33 /* 34 * Veritas filesystem driver - directory structure. 35 * 36 * This file contains the definition of the vxfs directory format. 37 */ 38 39 40 /* 41 * VxFS directory block header. 42 * 43 * This entry is the head of every filesystem block in a directory. 44 * It is used for free space management and additionally includes 45 * a hash for speeding up directory search (lookup). 46 * 47 * The hash may be empty and in fact we do not use it all in the 48 * Linux driver for now. 49 */ 50 struct vxfs_dirblk { 51 __fs16 d_free; /* free space in dirblock */ 52 __fs16 d_nhash; /* no of hash chains */ 53 __fs16 d_hash[1]; /* hash chain */ 54 }; 55 56 /* 57 * VXFS_NAMELEN is the maximum length of the d_name field 58 * of an VxFS directory entry. 59 */ 60 #define VXFS_NAMELEN 256 61 62 /* 63 * VxFS directory entry. 64 */ 65 struct vxfs_direct { 66 __fs32 d_ino; /* inode number */ 67 __fs16 d_reclen; /* record length */ 68 __fs16 d_namelen; /* d_name length */ 69 __fs16 d_hashnext; /* next hash entry */ 70 char d_name[VXFS_NAMELEN]; /* name */ 71 }; 72 73 /* 74 * VXFS_DIRPAD defines the directory entry boundaries, is _must_ be 75 * a multiple of four. 76 * VXFS_NAMEMIN is the length of a directory entry with a NULL d_name. 77 * VXFS_DIRROUND is an internal macros that rounds a length to a value 78 * usable for directory sizes. 79 * VXFS_DIRLEN calculates the directory entry size for an entry with 80 * a d_name with size len. 81 */ 82 #define VXFS_DIRPAD 4 83 #define VXFS_NAMEMIN offsetof(struct vxfs_direct, d_name) 84 #define VXFS_DIRROUND(len) ((VXFS_DIRPAD + (len) - 1) & ~(VXFS_DIRPAD -1)) 85 #define VXFS_DIRLEN(len) (VXFS_DIRROUND(VXFS_NAMEMIN + (len))) 86 87 /* 88 * VXFS_DIRBLKOV is the overhead of a specific dirblock. 89 */ 90 #define VXFS_DIRBLKOV(sbi, dbp) \ 91 ((sizeof(short) * fs16_to_cpu(sbi, dbp->d_nhash)) + 4) 92 93 #endif /* _VXFS_DIR_H_ */ 94