linux-stable/include/linux/sysv_fs.h
Lubomir Rintel 0bcaa65a56 fs/sysv: v7: adjust sanity checks for some volumes
Newly mkfs-ed filesystems from Seventh Edition have last modification time
set to zero, but are otherwise perfectly valid.

Also, tighten up other sanity checks to filter out most filesystems with

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11 08:59:22 -07:00

213 lines
9 KiB
C

#ifndef _LINUX_SYSV_FS_H
#define _LINUX_SYSV_FS_H
#define __packed2__ __attribute__((packed, aligned(2)))
#ifndef __KERNEL__
typedef u16 __fs16;
typedef u32 __fs16;
#endif
/* inode numbers are 16 bit */
typedef __fs16 sysv_ino_t;
/* Block numbers are 24 bit, sometimes stored in 32 bit.
On Coherent FS, they are always stored in PDP-11 manner: the least
significant 16 bits come last. */
typedef __fs32 sysv_zone_t;
/* 0 is non-existent */
#define SYSV_BADBL_INO 1 /* inode of bad blocks file */
#define SYSV_ROOT_INO 2 /* inode of root directory */
/* Xenix super-block data on disk */
#define XENIX_NICINOD 100 /* number of inode cache entries */
#define XENIX_NICFREE 100 /* number of free block list chunk entries */
struct xenix_super_block {
__fs16 s_isize; /* index of first data zone */
__fs32 s_fsize __packed2__; /* total number of zones of this fs */
/* the start of the free block list: */
__fs16 s_nfree; /* number of free blocks in s_free, <= XENIX_NICFREE */
sysv_zone_t s_free[XENIX_NICFREE]; /* first free block list chunk */
/* the cache of free inodes: */
__fs16 s_ninode; /* number of free inodes in s_inode, <= XENIX_NICINOD */
sysv_ino_t s_inode[XENIX_NICINOD]; /* some free inodes */
/* locks, not used by Linux: */
char s_flock; /* lock during free block list manipulation */
char s_ilock; /* lock during inode cache manipulation */
char s_fmod; /* super-block modified flag */
char s_ronly; /* flag whether fs is mounted read-only */
__fs32 s_time __packed2__; /* time of last super block update */
__fs32 s_tfree __packed2__; /* total number of free zones */
__fs16 s_tinode; /* total number of free inodes */
__fs16 s_dinfo[4]; /* device information ?? */
char s_fname[6]; /* file system volume name */
char s_fpack[6]; /* file system pack name */
char s_clean; /* set to 0x46 when filesystem is properly unmounted */
char s_fill[371];
s32 s_magic; /* version of file system */
__fs32 s_type; /* type of file system: 1 for 512 byte blocks
2 for 1024 byte blocks
3 for 2048 byte blocks */
};
/*
* SystemV FS comes in two variants:
* sysv2: System V Release 2 (e.g. Microport), structure elements aligned(2).
* sysv4: System V Release 4 (e.g. Consensys), structure elements aligned(4).
*/
#define SYSV_NICINOD 100 /* number of inode cache entries */
#define SYSV_NICFREE 50 /* number of free block list chunk entries */
/* SystemV4 super-block data on disk */
struct sysv4_super_block {
__fs16 s_isize; /* index of first data zone */
u16 s_pad0;
__fs32 s_fsize; /* total number of zones of this fs */
/* the start of the free block list: */
__fs16 s_nfree; /* number of free blocks in s_free, <= SYSV_NICFREE */
u16 s_pad1;
sysv_zone_t s_free[SYSV_NICFREE]; /* first free block list chunk */
/* the cache of free inodes: */
__fs16 s_ninode; /* number of free inodes in s_inode, <= SYSV_NICINOD */
u16 s_pad2;
sysv_ino_t s_inode[SYSV_NICINOD]; /* some free inodes */
/* locks, not used by Linux: */
char s_flock; /* lock during free block list manipulation */
char s_ilock; /* lock during inode cache manipulation */
char s_fmod; /* super-block modified flag */
char s_ronly; /* flag whether fs is mounted read-only */
__fs32 s_time; /* time of last super block update */
__fs16 s_dinfo[4]; /* device information ?? */
__fs32 s_tfree; /* total number of free zones */
__fs16 s_tinode; /* total number of free inodes */
u16 s_pad3;
char s_fname[6]; /* file system volume name */
char s_fpack[6]; /* file system pack name */
s32 s_fill[12];
__fs32 s_state; /* file system state: 0x7c269d38-s_time means clean */
s32 s_magic; /* version of file system */
__fs32 s_type; /* type of file system: 1 for 512 byte blocks
2 for 1024 byte blocks */
};
/* SystemV2 super-block data on disk */
struct sysv2_super_block {
__fs16 s_isize; /* index of first data zone */
__fs32 s_fsize __packed2__; /* total number of zones of this fs */
/* the start of the free block list: */
__fs16 s_nfree; /* number of free blocks in s_free, <= SYSV_NICFREE */
sysv_zone_t s_free[SYSV_NICFREE]; /* first free block list chunk */
/* the cache of free inodes: */
__fs16 s_ninode; /* number of free inodes in s_inode, <= SYSV_NICINOD */
sysv_ino_t s_inode[SYSV_NICINOD]; /* some free inodes */
/* locks, not used by Linux: */
char s_flock; /* lock during free block list manipulation */
char s_ilock; /* lock during inode cache manipulation */
char s_fmod; /* super-block modified flag */
char s_ronly; /* flag whether fs is mounted read-only */
__fs32 s_time __packed2__; /* time of last super block update */
__fs16 s_dinfo[4]; /* device information ?? */
__fs32 s_tfree __packed2__; /* total number of free zones */
__fs16 s_tinode; /* total number of free inodes */
char s_fname[6]; /* file system volume name */
char s_fpack[6]; /* file system pack name */
s32 s_fill[14];
__fs32 s_state; /* file system state: 0xcb096f43 means clean */
s32 s_magic; /* version of file system */
__fs32 s_type; /* type of file system: 1 for 512 byte blocks
2 for 1024 byte blocks */
};
/* V7 super-block data on disk */
#define V7_NICINOD 100 /* number of inode cache entries */
#define V7_NICFREE 50 /* number of free block list chunk entries */
struct v7_super_block {
__fs16 s_isize; /* index of first data zone */
__fs32 s_fsize __packed2__; /* total number of zones of this fs */
/* the start of the free block list: */
__fs16 s_nfree; /* number of free blocks in s_free, <= V7_NICFREE */
sysv_zone_t s_free[V7_NICFREE]; /* first free block list chunk */
/* the cache of free inodes: */
__fs16 s_ninode; /* number of free inodes in s_inode, <= V7_NICINOD */
sysv_ino_t s_inode[V7_NICINOD]; /* some free inodes */
/* locks, not used by Linux or V7: */
char s_flock; /* lock during free block list manipulation */
char s_ilock; /* lock during inode cache manipulation */
char s_fmod; /* super-block modified flag */
char s_ronly; /* flag whether fs is mounted read-only */
__fs32 s_time __packed2__; /* time of last super block update */
/* the following fields are not maintained by V7: */
__fs32 s_tfree __packed2__; /* total number of free zones */
__fs16 s_tinode; /* total number of free inodes */
__fs16 s_m; /* interleave factor */
__fs16 s_n; /* interleave factor */
char s_fname[6]; /* file system name */
char s_fpack[6]; /* file system pack name */
};
/* Constants to aid sanity checking */
/* This is not a hard limit, nor enforced by v7 kernel. It's actually just
* the limit used by Seventh Edition's ls, though is high enough to assume
* that no reasonable file system would have that much entries in root
* directory. Thus, if we see anything higher, we just probably got the
* endiannes wrong. */
#define V7_NFILES 1024
/* The disk addresses are three-byte (despite direct block addresses being
* aligned word-wise in inode). If the most significant byte is non-zero,
* something is most likely wrong (not a filesystem, bad bytesex). */
#define V7_MAXSIZE 0x00ffffff
/* Coherent super-block data on disk */
#define COH_NICINOD 100 /* number of inode cache entries */
#define COH_NICFREE 64 /* number of free block list chunk entries */
struct coh_super_block {
__fs16 s_isize; /* index of first data zone */
__fs32 s_fsize __packed2__; /* total number of zones of this fs */
/* the start of the free block list: */
__fs16 s_nfree; /* number of free blocks in s_free, <= COH_NICFREE */
sysv_zone_t s_free[COH_NICFREE] __packed2__; /* first free block list chunk */
/* the cache of free inodes: */
__fs16 s_ninode; /* number of free inodes in s_inode, <= COH_NICINOD */
sysv_ino_t s_inode[COH_NICINOD]; /* some free inodes */
/* locks, not used by Linux: */
char s_flock; /* lock during free block list manipulation */
char s_ilock; /* lock during inode cache manipulation */
char s_fmod; /* super-block modified flag */
char s_ronly; /* flag whether fs is mounted read-only */
__fs32 s_time __packed2__; /* time of last super block update */
__fs32 s_tfree __packed2__; /* total number of free zones */
__fs16 s_tinode; /* total number of free inodes */
__fs16 s_interleave_m; /* interleave factor */
__fs16 s_interleave_n;
char s_fname[6]; /* file system volume name */
char s_fpack[6]; /* file system pack name */
__fs32 s_unique; /* zero, not used */
};
/* SystemV/Coherent inode data on disk */
struct sysv_inode {
__fs16 i_mode;
__fs16 i_nlink;
__fs16 i_uid;
__fs16 i_gid;
__fs32 i_size;
u8 i_data[3*(10+1+1+1)];
u8 i_gen;
__fs32 i_atime; /* time of last access */
__fs32 i_mtime; /* time of last modification */
__fs32 i_ctime; /* time of creation */
};
/* SystemV/Coherent directory entry on disk */
#define SYSV_NAMELEN 14 /* max size of name in struct sysv_dir_entry */
struct sysv_dir_entry {
sysv_ino_t inode;
char name[SYSV_NAMELEN]; /* up to 14 characters, the rest are zeroes */
};
#define SYSV_DIRSIZE sizeof(struct sysv_dir_entry) /* size of every directory entry */
#endif /* _LINUX_SYSV_FS_H */