linux/include/linux/sysv_fs.h
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   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _LINUX_SYSV_FS_H
   3#define _LINUX_SYSV_FS_H
   4
   5#define __packed2__     __attribute__((packed, aligned(2)))
   6
   7
   8#ifndef __KERNEL__
   9typedef u16 __fs16;
  10typedef u32 __fs16;
  11#endif
  12
  13/* inode numbers are 16 bit */
  14typedef __fs16 sysv_ino_t;
  15
  16/* Block numbers are 24 bit, sometimes stored in 32 bit.
  17   On Coherent FS, they are always stored in PDP-11 manner: the least
  18   significant 16 bits come last. */
  19typedef __fs32 sysv_zone_t;
  20
  21/* 0 is non-existent */
  22#define SYSV_BADBL_INO  1       /* inode of bad blocks file */
  23#define SYSV_ROOT_INO   2       /* inode of root directory */
  24
  25
  26/* Xenix super-block data on disk */
  27#define XENIX_NICINOD   100     /* number of inode cache entries */
  28#define XENIX_NICFREE   100     /* number of free block list chunk entries */
  29struct xenix_super_block {
  30        __fs16          s_isize; /* index of first data zone */
  31        __fs32          s_fsize __packed2__; /* total number of zones of this fs */
  32        /* the start of the free block list: */
  33        __fs16          s_nfree;        /* number of free blocks in s_free, <= XENIX_NICFREE */
  34        sysv_zone_t     s_free[XENIX_NICFREE]; /* first free block list chunk */
  35        /* the cache of free inodes: */
  36        __fs16          s_ninode; /* number of free inodes in s_inode, <= XENIX_NICINOD */
  37        sysv_ino_t      s_inode[XENIX_NICINOD]; /* some free inodes */
  38        /* locks, not used by Linux: */
  39        char            s_flock;        /* lock during free block list manipulation */
  40        char            s_ilock;        /* lock during inode cache manipulation */
  41        char            s_fmod;         /* super-block modified flag */
  42        char            s_ronly;        /* flag whether fs is mounted read-only */
  43        __fs32          s_time __packed2__; /* time of last super block update */
  44        __fs32          s_tfree __packed2__; /* total number of free zones */
  45        __fs16          s_tinode;       /* total number of free inodes */
  46        __fs16          s_dinfo[4];     /* device information ?? */
  47        char            s_fname[6];     /* file system volume name */
  48        char            s_fpack[6];     /* file system pack name */
  49        char            s_clean;        /* set to 0x46 when filesystem is properly unmounted */
  50        char            s_fill[371];
  51        s32             s_magic;        /* version of file system */
  52        __fs32          s_type;         /* type of file system: 1 for 512 byte blocks
  53                                                                2 for 1024 byte blocks
  54                                                                3 for 2048 byte blocks */
  55                                                                
  56};
  57
  58/*
  59 * SystemV FS comes in two variants:
  60 * sysv2: System V Release 2 (e.g. Microport), structure elements aligned(2).
  61 * sysv4: System V Release 4 (e.g. Consensys), structure elements aligned(4).
  62 */
  63#define SYSV_NICINOD    100     /* number of inode cache entries */
  64#define SYSV_NICFREE    50      /* number of free block list chunk entries */
  65
  66/* SystemV4 super-block data on disk */
  67struct sysv4_super_block {
  68        __fs16  s_isize;        /* index of first data zone */
  69        u16     s_pad0;
  70        __fs32  s_fsize;        /* total number of zones of this fs */
  71        /* the start of the free block list: */
  72        __fs16  s_nfree;        /* number of free blocks in s_free, <= SYSV_NICFREE */
  73        u16     s_pad1;
  74        sysv_zone_t     s_free[SYSV_NICFREE]; /* first free block list chunk */
  75        /* the cache of free inodes: */
  76        __fs16  s_ninode;       /* number of free inodes in s_inode, <= SYSV_NICINOD */
  77        u16     s_pad2;
  78        sysv_ino_t     s_inode[SYSV_NICINOD]; /* some free inodes */
  79        /* locks, not used by Linux: */
  80        char    s_flock;        /* lock during free block list manipulation */
  81        char    s_ilock;        /* lock during inode cache manipulation */
  82        char    s_fmod;         /* super-block modified flag */
  83        char    s_ronly;        /* flag whether fs is mounted read-only */
  84        __fs32  s_time;         /* time of last super block update */
  85        __fs16  s_dinfo[4];     /* device information ?? */
  86        __fs32  s_tfree;        /* total number of free zones */
  87        __fs16  s_tinode;       /* total number of free inodes */
  88        u16     s_pad3;
  89        char    s_fname[6];     /* file system volume name */
  90        char    s_fpack[6];     /* file system pack name */
  91        s32     s_fill[12];
  92        __fs32  s_state;        /* file system state: 0x7c269d38-s_time means clean */
  93        s32     s_magic;        /* version of file system */
  94        __fs32  s_type;         /* type of file system: 1 for 512 byte blocks
  95                                                                2 for 1024 byte blocks */
  96};
  97
  98/* SystemV2 super-block data on disk */
  99struct sysv2_super_block {
 100        __fs16  s_isize;                /* index of first data zone */
 101        __fs32  s_fsize __packed2__;    /* total number of zones of this fs */
 102        /* the start of the free block list: */
 103        __fs16  s_nfree;                /* number of free blocks in s_free, <= SYSV_NICFREE */
 104        sysv_zone_t s_free[SYSV_NICFREE];       /* first free block list chunk */
 105        /* the cache of free inodes: */
 106        __fs16  s_ninode;               /* number of free inodes in s_inode, <= SYSV_NICINOD */
 107        sysv_ino_t     s_inode[SYSV_NICINOD]; /* some free inodes */
 108        /* locks, not used by Linux: */
 109        char    s_flock;                /* lock during free block list manipulation */
 110        char    s_ilock;                /* lock during inode cache manipulation */
 111        char    s_fmod;                 /* super-block modified flag */
 112        char    s_ronly;                /* flag whether fs is mounted read-only */
 113        __fs32  s_time __packed2__;     /* time of last super block update */
 114        __fs16  s_dinfo[4];             /* device information ?? */
 115        __fs32  s_tfree __packed2__;    /* total number of free zones */
 116        __fs16  s_tinode;               /* total number of free inodes */
 117        char    s_fname[6];             /* file system volume name */
 118        char    s_fpack[6];             /* file system pack name */
 119        s32     s_fill[14];
 120        __fs32  s_state;                /* file system state: 0xcb096f43 means clean */
 121        s32     s_magic;                /* version of file system */
 122        __fs32  s_type;                 /* type of file system: 1 for 512 byte blocks
 123                                                                2 for 1024 byte blocks */
 124};
 125
 126/* V7 super-block data on disk */
 127#define V7_NICINOD     100     /* number of inode cache entries */
 128#define V7_NICFREE     50      /* number of free block list chunk entries */
 129struct v7_super_block {
 130        __fs16 s_isize;        /* index of first data zone */
 131        __fs32 s_fsize __packed2__; /* total number of zones of this fs */
 132        /* the start of the free block list: */
 133        __fs16 s_nfree;        /* number of free blocks in s_free, <= V7_NICFREE */
 134        sysv_zone_t s_free[V7_NICFREE]; /* first free block list chunk */
 135        /* the cache of free inodes: */
 136        __fs16 s_ninode;       /* number of free inodes in s_inode, <= V7_NICINOD */
 137        sysv_ino_t      s_inode[V7_NICINOD]; /* some free inodes */
 138        /* locks, not used by Linux or V7: */
 139        char    s_flock;        /* lock during free block list manipulation */
 140        char    s_ilock;        /* lock during inode cache manipulation */
 141        char    s_fmod;         /* super-block modified flag */
 142        char    s_ronly;        /* flag whether fs is mounted read-only */
 143        __fs32  s_time __packed2__; /* time of last super block update */
 144        /* the following fields are not maintained by V7: */
 145        __fs32  s_tfree __packed2__; /* total number of free zones */
 146        __fs16  s_tinode;       /* total number of free inodes */
 147        __fs16  s_m;            /* interleave factor */
 148        __fs16  s_n;            /* interleave factor */
 149        char    s_fname[6];     /* file system name */
 150        char    s_fpack[6];     /* file system pack name */
 151};
 152/* Constants to aid sanity checking */
 153/* This is not a hard limit, nor enforced by v7 kernel. It's actually just
 154 * the limit used by Seventh Edition's ls, though is high enough to assume
 155 * that no reasonable file system would have that much entries in root
 156 * directory. Thus, if we see anything higher, we just probably got the
 157 * endiannes wrong. */
 158#define V7_NFILES       1024
 159/* The disk addresses are three-byte (despite direct block addresses being
 160 * aligned word-wise in inode). If the most significant byte is non-zero,
 161 * something is most likely wrong (not a filesystem, bad bytesex). */
 162#define V7_MAXSIZE      0x00ffffff
 163
 164/* Coherent super-block data on disk */
 165#define COH_NICINOD     100     /* number of inode cache entries */
 166#define COH_NICFREE     64      /* number of free block list chunk entries */
 167struct coh_super_block {
 168        __fs16          s_isize;        /* index of first data zone */
 169        __fs32          s_fsize __packed2__; /* total number of zones of this fs */
 170        /* the start of the free block list: */
 171        __fs16 s_nfree; /* number of free blocks in s_free, <= COH_NICFREE */
 172        sysv_zone_t     s_free[COH_NICFREE] __packed2__; /* first free block list chunk */
 173        /* the cache of free inodes: */
 174        __fs16          s_ninode;       /* number of free inodes in s_inode, <= COH_NICINOD */
 175        sysv_ino_t      s_inode[COH_NICINOD]; /* some free inodes */
 176        /* locks, not used by Linux: */
 177        char            s_flock;        /* lock during free block list manipulation */
 178        char            s_ilock;        /* lock during inode cache manipulation */
 179        char            s_fmod;         /* super-block modified flag */
 180        char            s_ronly;        /* flag whether fs is mounted read-only */
 181        __fs32          s_time __packed2__; /* time of last super block update */
 182        __fs32          s_tfree __packed2__; /* total number of free zones */
 183        __fs16          s_tinode;       /* total number of free inodes */
 184        __fs16          s_interleave_m; /* interleave factor */
 185        __fs16          s_interleave_n;
 186        char            s_fname[6];     /* file system volume name */
 187        char            s_fpack[6];     /* file system pack name */
 188        __fs32          s_unique;       /* zero, not used */
 189};
 190
 191/* SystemV/Coherent inode data on disk */
 192struct sysv_inode {
 193        __fs16 i_mode;
 194        __fs16 i_nlink;
 195        __fs16 i_uid;
 196        __fs16 i_gid;
 197        __fs32 i_size;
 198        u8  i_data[3*(10+1+1+1)];
 199        u8  i_gen;
 200        __fs32 i_atime; /* time of last access */
 201        __fs32 i_mtime; /* time of last modification */
 202        __fs32 i_ctime; /* time of creation */
 203};
 204
 205/* SystemV/Coherent directory entry on disk */
 206#define SYSV_NAMELEN    14      /* max size of name in struct sysv_dir_entry */
 207struct sysv_dir_entry {
 208        sysv_ino_t inode;
 209        char name[SYSV_NAMELEN]; /* up to 14 characters, the rest are zeroes */
 210};
 211
 212#define SYSV_DIRSIZE    sizeof(struct sysv_dir_entry)   /* size of every directory entry */
 213
 214#endif /* _LINUX_SYSV_FS_H */
 215