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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 includes20 * 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 the23 * Linux driver for now.24 */25struct 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 field33 * of an VxFS directory entry.34 */35#define VXFS_NAMELEN 25636 37/*38 * VxFS directory entry.39 */40struct 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_ be50 * 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 value53 * usable for directory sizes.54 * VXFS_DIRLEN calculates the directory entry size for an entry with55 * a d_name with size len.56 */57#define VXFS_DIRPAD 458#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