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/* $NetBSD: minixfs3.h,v 1.5 2013/06/23 07:28:36 dholland Exp $ */
/*-
* Copyright (c) 2012
* Vrije Universiteit, Amsterdam, The Netherlands. All rights reserved.
*
* Author: Evgeniy Ivanov
*
* 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.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 FOUNDATION 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 MINIX_FS_3_H
#define MINIX_FS_3_H
FS_DEF(minixfs3);
#if !defined(__minix)
typedef uint32_t zone_t;
typedef uint16_t zone1_t;
typedef uint32_t block_t;
#endif /* !defined(__minix) */
#define NR_DZONES 7 /* # direct zone numbers in an inode */
#define NR_TZONES 10 /* total # zone numbers in an inode */
#define NIADDR 2 /* Indirect addresses in inode */
struct mfs_dinode {
uint16_t mdi_mode; /* file type, protection, etc. */
uint16_t mdi_nlinks; /* how many links to this file */
int16_t mdi_uid; /* user id of the file's owner */
uint16_t mdi_gid; /* group number */
uint32_t mdi_size; /* current file size in bytes */
uint32_t mdi_atime; /* time of last access */
uint32_t mdi_mtime; /* when was file data last changed */
uint32_t mdi_ctime; /* when was inode itself changed */
zone_t mdi_zone[NR_TZONES]; /* zone numbers for direct, ind, and
dbl ind */
};
/* Maximum Minix MFS on-disk directory filename.
* MFS uses 'struct direct' to write and parse
* directory entries, so this can't be changed
* without breaking filesystems.
*/
#define MFS_DIRSIZ 60
struct mfs_direct {
uint32_t mfsd_ino;
char mfsd_name[MFS_DIRSIZ];
} __packed;
struct mfs_sblock {
uint32_t mfs_ninodes; /* # usable inodes on the minor device */
zone1_t mfs_nzones; /* total device size, including bit maps etc */
int16_t mfs_imap_blocks; /* # of blocks used by inode bit map */
int16_t mfs_zmap_blocks; /* # of blocks used by zone bit map */
zone1_t mfs_firstdatazone_old;/* number of first data zone (small) */
int16_t mfs_log_zone_size; /* log2 of blocks/zone */
int16_t mfs_pad; /* try to avoid compiler-dependent padding */
int32_t mfs_max_size; /* maximum file size on this device */
zone_t mfs_zones; /* number of zones (replaces s_nzones in V2) */
int16_t mfs_magic; /* magic number to recognize super-blocks */
int16_t mfs_pad2; /* try to avoid compiler-dependent padding */
uint16_t mfs_block_size; /* block size in bytes. */
char mfs_disk_version; /* filesystem format sub-version */
/* The following items are only used when the super_block is in memory,
* mfs_inodes_per_block must be the firs one (see SBSIZE)
*/
unsigned mfs_inodes_per_block; /* precalculated from magic number */
zone_t mfs_firstdatazone; /* number of first data zone (big) */
int32_t mfs_bshift; /* ``lblkno'' calc of logical blkno */
int32_t mfs_bmask; /* ``blkoff'' calc of blk offsets */
int64_t mfs_qbmask; /* ~fs_bmask - for use with quad size */
int32_t mfs_fsbtodb; /* fsbtodb and dbtofsb shift constant */
};
#define LOG_MINBSIZE 10
#define MINBSIZE (1 << LOG_MINBSIZE)
#define SUPER_MAGIC 0x4d5a /* magic # for MFSv3 file systems */
#define ROOT_INODE ((uint32_t) 1) /* inode number for root directory */
#define SUPER_BLOCK_OFF (1024) /* bytes offset */
#define START_BLOCK ((block_t) 2) /* first fs block (not counting SB) */
/* # bytes/dir entry */
#define DIR_ENTRY_SIZE sizeof(struct mfs_direct)
/* # dir entries/blk */
#define NR_DIR_ENTRIES(fs) ((fs)->mfs_block_size/DIR_ENTRY_SIZE)
/* mfs_sblock on-disk part size */
#define SBSIZE offsetof(struct mfs_sblock, mfs_inodes_per_block)
#define ZONE_NUM_SIZE sizeof(zone_t) /* # bytes in zone */
#define INODE_SIZE sizeof(struct mfs_dinode) /* bytes in dsk ino */
/* # zones/indir block */
#define MFS_NINDIR(fs) ((fs)->mfs_block_size/ZONE_NUM_SIZE)
#define NO_ZONE ((zone_t) 0) /* absence of a zone number */
#define NO_BLOCK ((block_t) 0) /* absence of a block number */
/* Turn file system block numbers into disk block addresses */
#define MFS_FSBTODB(fs, b) ((b) << (fs)->mfs_fsbtodb)
#define ino_to_fsba(fs, x) \
(((x) - 1) / (fs)->mfs_inodes_per_block + \
START_BLOCK + (fs)->mfs_imap_blocks + (fs)->mfs_zmap_blocks)
#define ino_to_fsbo(fs, x) (((x) - 1) % (fs)->mfs_inodes_per_block)
/*
* MFS metadatas are stored in little-endian byte order. These macros
* helps reading theses metadatas.
*/
#if BYTE_ORDER == LITTLE_ENDIAN
# define fs2h16(x) (x)
# define fs2h32(x) (x)
# define mfs_sbload(old, new) \
memcpy((new), (old), SBSIZE);
# define mfs_iload(old, new) \
memcpy((new),(old),sizeof(struct mfs_dinode))
#else
void minixfs3_sb_bswap(struct mfs_sblock *, struct mfs_sblock *);
void minixfs3_i_bswap(struct mfs_dinode *, struct mfs_dinode *);
# define fs2h16(x) bswap16(x)
# define fs2h32(x) bswap32(x)
# define mfs_sbload(old, new) minixfs3_sb_bswap((old), (new))
# define mfs_iload(old, new) minixfs3_i_bswap((old), (new))
#endif /* BYTE_ORDER == LITTLE_ENDIAN */
/*
* The following macros optimize certain frequently calculated
* quantities by using shifts and masks in place of divisions
* modulos and multiplications.
*/
#define mfs_blkoff(fs, loc) /* calculates (loc % fs->mfs_bsize) */ \
((loc) & (fs)->mfs_qbmask)
#define mfs_lblkno(fs, loc) /* calculates (loc / fs->mfs_bsize) */ \
((loc) >> (fs)->mfs_bshift)
/* Flag bits for i_mode in the inode. */
#define I_TYPE 0170000 /* this field gives inode type */
#define I_UNIX_SOCKET 0140000 /* unix domain socket */
#define I_SYMBOLIC_LINK 0120000 /* file is a symbolic link */
#define I_REGULAR 0100000 /* regular file, not dir or special */
#define I_BLOCK_SPECIAL 0060000 /* block special file */
#define I_DIRECTORY 0040000 /* file is a directory */
#define I_CHAR_SPECIAL 0020000 /* character special file */
#define I_NAMED_PIPE 0010000 /* named pipe (FIFO) */
#define I_SET_UID_BIT 0004000 /* set effective uid_t on exec */
#define I_SET_GID_BIT 0002000 /* set effective gid_t on exec */
#define I_SET_STCKY_BIT 0001000 /* sticky bit */
#define ALL_MODES 0007777 /* all bits for user, group and others */
#define RWX_MODES 0000777 /* mode bits for RWX only */
#define R_BIT 0000004 /* Rwx protection bit */
#define W_BIT 0000002 /* rWx protection bit */
#define X_BIT 0000001 /* rwX protection bit */
#define I_NOT_ALLOC 0000000 /* this inode is free */
#endif /* MINIX_FS_3_H */
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