fs/omfs/omfs_fs.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _OMFS_FS_H
   3 #define _OMFS_FS_H
   4
   5 /* OMFS On-disk structures */
   6
   7 #define OMFS_MAGIC 0xC2993D87
   8 #define OMFS_IMAGIC 0xD2
   9
  10 #define OMFS_DIR 'D'
  11 #define OMFS_FILE 'F'
  12 #define OMFS_INODE_NORMAL 'e'
  13 #define OMFS_INODE_CONTINUATION 'c'
  14 #define OMFS_INODE_SYSTEM 's'
  15 #define OMFS_NAMELEN 256
  16 #define OMFS_DIR_START 0x1b8
  17 #define OMFS_EXTENT_START 0x1d0
  18 #define OMFS_EXTENT_CONT 0x40
  19 #define OMFS_XOR_COUNT 19
  20 #define OMFS_MAX_BLOCK_SIZE 8192
  21 #define OMFS_MAX_CLUSTER_SIZE 8
  22 #define OMFS_MAX_BLOCKS (1ul << 31)
  23
  24 struct omfs_super_block {
  25         char s_fill1[256];
  26         __be64 s_root_block;            /* block number of omfs_root_block */
  27         __be64 s_num_blocks;            /* total number of FS blocks */
  28         __be32 s_magic;                 /* OMFS_MAGIC */
  29         __be32 s_blocksize;             /* size of a block */
  30         __be32 s_mirrors;               /* # of mirrors of system blocks */
  31         __be32 s_sys_blocksize;         /* size of non-data blocks */
  32 };
  33
  34 struct omfs_header {
  35         __be64 h_self;                  /* FS block where this is located */
  36         __be32 h_body_size;             /* size of useful data after header */
  37         __be16 h_crc;                   /* crc-ccitt of body_size bytes */
  38         char h_fill1[2];
  39         u8 h_version;                   /* version, always 1 */
  40         char h_type;                    /* OMFS_INODE_X */
  41         u8 h_magic;                     /* OMFS_IMAGIC */
  42         u8 h_check_xor;                 /* XOR of header bytes before this */
  43         __be32 h_fill2;
  44 };
  45
  46 struct omfs_root_block {
  47         struct omfs_header r_head;      /* header */
  48         __be64 r_fill1;
  49         __be64 r_num_blocks;            /* total number of FS blocks */
  50         __be64 r_root_dir;              /* block # of root directory */
  51         __be64 r_bitmap;                /* block # of free space bitmap */
  52         __be32 r_blocksize;             /* size of a block */
  53         __be32 r_clustersize;           /* size allocated for data blocks */
  54         __be64 r_mirrors;               /* # of mirrors of system blocks */
  55         char r_name[OMFS_NAMELEN];      /* partition label */
  56 };
  57
  58 struct omfs_inode {
  59         struct omfs_header i_head;      /* header */
  60         __be64 i_parent;                /* parent containing this inode */
  61         __be64 i_sibling;               /* next inode in hash bucket */
  62         __be64 i_ctime;                 /* ctime, in milliseconds */
  63         char i_fill1[35];
  64         char i_type;                    /* OMFS_[DIR,FILE] */
  65         __be32 i_fill2;
  66         char i_fill3[64];
  67         char i_name[OMFS_NAMELEN];      /* filename */
  68         __be64 i_size;                  /* size of file, in bytes */
  69 };
  70
  71 struct omfs_extent_entry {
  72         __be64 e_cluster;               /* start location of a set of blocks */
  73         __be64 e_blocks;                /* number of blocks after e_cluster */
  74 };
  75
  76 struct omfs_extent {
  77         __be64 e_next;                  /* next extent table location */
  78         __be32 e_extent_count;          /* total # extents in this table */
  79         __be32 e_fill;
  80         struct omfs_extent_entry e_entry;       /* start of extent entries */
  81 };
  82
  83 #endif