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
24struct 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
34struct 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
46struct 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
58struct 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
71struct 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
76struct 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
84