fs/omfs/omfs_fs.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 #ifndef _OMFS_FS_H
0003 #define _OMFS_FS_H
0004
0005 /* OMFS On-disk structures */
0006
0007 #define OMFS_MAGIC 0xC2993D87
0008 #define OMFS_IMAGIC 0xD2
0009
0010 #define OMFS_DIR 'D'
0011 #define OMFS_FILE 'F'
0012 #define OMFS_INODE_NORMAL 'e'
0013 #define OMFS_INODE_CONTINUATION 'c'
0014 #define OMFS_INODE_SYSTEM 's'
0015 #define OMFS_NAMELEN 256
0016 #define OMFS_DIR_START 0x1b8
0017 #define OMFS_EXTENT_START 0x1d0
0018 #define OMFS_EXTENT_CONT 0x40
0019 #define OMFS_XOR_COUNT 19
0020 #define OMFS_MAX_BLOCK_SIZE 8192
0021 #define OMFS_MAX_CLUSTER_SIZE 8
0022 #define OMFS_MAX_BLOCKS (1ul << 31)
0023
0024 struct omfs_super_block {
0025     char s_fill1[256];
0026     __be64 s_root_block;        /* block number of omfs_root_block */
0027     __be64 s_num_blocks;        /* total number of FS blocks */
0028     __be32 s_magic;         /* OMFS_MAGIC */
0029     __be32 s_blocksize;     /* size of a block */
0030     __be32 s_mirrors;       /* # of mirrors of system blocks */
0031     __be32 s_sys_blocksize;     /* size of non-data blocks */
0032 };
0033
0034 struct omfs_header {
0035     __be64 h_self;          /* FS block where this is located */
0036     __be32 h_body_size;     /* size of useful data after header */
0037     __be16 h_crc;           /* crc-ccitt of body_size bytes */
0038     char h_fill1[2];
0039     u8 h_version;           /* version, always 1 */
0040     char h_type;            /* OMFS_INODE_X */
0041     u8 h_magic;         /* OMFS_IMAGIC */
0042     u8 h_check_xor;         /* XOR of header bytes before this */
0043     __be32 h_fill2;
0044 };
0045
0046 struct omfs_root_block {
0047     struct omfs_header r_head;  /* header */
0048     __be64 r_fill1;
0049     __be64 r_num_blocks;        /* total number of FS blocks */
0050     __be64 r_root_dir;      /* block # of root directory */
0051     __be64 r_bitmap;        /* block # of free space bitmap */
0052     __be32 r_blocksize;     /* size of a block */
0053     __be32 r_clustersize;       /* size allocated for data blocks */
0054     __be64 r_mirrors;       /* # of mirrors of system blocks */
0055     char r_name[OMFS_NAMELEN];  /* partition label */
0056 };
0057
0058 struct omfs_inode {
0059     struct omfs_header i_head;  /* header */
0060     __be64 i_parent;        /* parent containing this inode */
0061     __be64 i_sibling;       /* next inode in hash bucket */
0062     __be64 i_ctime;         /* ctime, in milliseconds */
0063     char i_fill1[35];
0064     char i_type;            /* OMFS_[DIR,FILE] */
0065     __be32 i_fill2;
0066     char i_fill3[64];
0067     char i_name[OMFS_NAMELEN];  /* filename */
0068     __be64 i_size;          /* size of file, in bytes */
0069 };
0070
0071 struct omfs_extent_entry {
0072     __be64 e_cluster;       /* start location of a set of blocks */
0073     __be64 e_blocks;        /* number of blocks after e_cluster */
0074 };
0075
0076 struct omfs_extent {
0077     __be64 e_next;          /* next extent table location */
0078     __be32 e_extent_count;      /* total # extents in this table */
0079     __be32 e_fill;
0080     struct omfs_extent_entry e_entry;   /* start of extent entries */
0081 };
0082
0083 #endif