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Diffstat (limited to 'fs/freevxfs/vxfs_dir.h')
-rw-r--r-- | fs/freevxfs/vxfs_dir.h | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/fs/freevxfs/vxfs_dir.h b/fs/freevxfs/vxfs_dir.h new file mode 100644 index 00000000000..8a4dfef1dda --- /dev/null +++ b/fs/freevxfs/vxfs_dir.h @@ -0,0 +1,92 @@ +/* + * Copyright (c) 2000-2001 Christoph Hellwig. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions, and the following disclaimer, + * without modification. + * 2. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * Alternatively, this software may be distributed under the terms of the + * GNU General Public License ("GPL"). + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR + * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + */ +#ifndef _VXFS_DIR_H_ +#define _VXFS_DIR_H_ + +/* + * Veritas filesystem driver - directory structure. + * + * This file contains the definition of the vxfs directory format. + */ + + +/* + * VxFS directory block header. + * + * This entry is the head of every filesystem block in a directory. + * It is used for free space managment and additionally includes + * a hash for speeding up directory search (lookup). + * + * The hash may be empty and in fact we do not use it all in the + * Linux driver for now. + */ +struct vxfs_dirblk { + u_int16_t d_free; /* free space in dirblock */ + u_int16_t d_nhash; /* no of hash chains */ + u_int16_t d_hash[1]; /* hash chain */ +}; + +/* + * VXFS_NAMELEN is the maximum length of the d_name field + * of an VxFS directory entry. + */ +#define VXFS_NAMELEN 256 + +/* + * VxFS directory entry. + */ +struct vxfs_direct { + vx_ino_t d_ino; /* inode number */ + u_int16_t d_reclen; /* record length */ + u_int16_t d_namelen; /* d_name length */ + u_int16_t d_hashnext; /* next hash entry */ + char d_name[VXFS_NAMELEN]; /* name */ +}; + +/* + * VXFS_DIRPAD defines the directory entry boundaries, is _must_ be + * a multiple of four. + * VXFS_NAMEMIN is the length of a directory entry with a NULL d_name. + * VXFS_DIRROUND is an internal macros that rounds a length to a value + * usable for directory sizes. + * VXFS_DIRLEN calculates the directory entry size for an entry with + * a d_name with size len. + */ +#define VXFS_DIRPAD 4 +#define VXFS_NAMEMIN ((int)((struct vxfs_direct *)0)->d_name) +#define VXFS_DIRROUND(len) ((VXFS_DIRPAD + (len) - 1) & ~(VXFS_DIRPAD -1)) +#define VXFS_DIRLEN(len) (VXFS_DIRROUND(VXFS_NAMEMIN + (len))) + +/* + * VXFS_DIRBLKOV is the overhead of a specific dirblock. + */ +#define VXFS_DIRBLKOV(dbp) ((sizeof(short) * dbp->d_nhash) + 4) + +#endif /* _VXFS_DIR_H_ */ |