1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (c) 2000-2001 Christoph Hellwig. 4 */ 5 #ifndef _VXFS_DIR_H_ 6 #define _VXFS_DIR_H_ 7 8 /* 9 * Veritas filesystem driver - directory structure. 10 * 11 * This file contains the definition of the vxfs directory format. 12 */ 13 14 15 /* 16 * VxFS directory block header. 17 * 18 * This entry is the head of every filesystem block in a directory. 19 * It is used for free space management and additionally includes 20 * a hash for speeding up directory search (lookup). 21 * 22 * The hash may be empty and in fact we do not use it all in the 23 * Linux driver for now. 24 */ 25 struct vxfs_dirblk { 26 __fs16 d_free; /* free space in dirblock */ 27 __fs16 d_nhash; /* no of hash chains */ 28 __fs16 d_hash[1]; /* hash chain */ 29 }; 30 31 /* 32 * VXFS_NAMELEN is the maximum length of the d_name field 33 * of an VxFS directory entry. 34 */ 35 #define VXFS_NAMELEN 256 36 37 /* 38 * VxFS directory entry. 39 */ 40 struct vxfs_direct { 41 __fs32 d_ino; /* inode number */ 42 __fs16 d_reclen; /* record length */ 43 __fs16 d_namelen; /* d_name length */ 44 __fs16 d_hashnext; /* next hash entry */ 45 char d_name[VXFS_NAMELEN]; /* name */ 46 }; 47 48 /* 49 * VXFS_DIRPAD defines the directory entry boundaries, is _must_ be 50 * a multiple of four. 51 * VXFS_NAMEMIN is the length of a directory entry with a NULL d_name. 52 * VXFS_DIRROUND is an internal macros that rounds a length to a value 53 * usable for directory sizes. 54 * VXFS_DIRLEN calculates the directory entry size for an entry with 55 * a d_name with size len. 56 */ 57 #define VXFS_DIRPAD 4 58 #define VXFS_NAMEMIN offsetof(struct vxfs_direct, d_name) 59 #define VXFS_DIRROUND(len) ((VXFS_DIRPAD + (len) - 1) & ~(VXFS_DIRPAD -1)) 60 #define VXFS_DIRLEN(len) (VXFS_DIRROUND(VXFS_NAMEMIN + (len))) 61 62 /* 63 * VXFS_DIRBLKOV is the overhead of a specific dirblock. 64 */ 65 #define VXFS_DIRBLKOV(sbi, dbp) \ 66 ((sizeof(short) * fs16_to_cpu(sbi, dbp->d_nhash)) + 4) 67 68 #endif /* _VXFS_DIR_H_ */ 69