xref: /linux/fs/omfs/omfs_fs.h (revision a2cce7a9f1b8cc3d4edce106fb971529f1d4d9ce)
1 #ifndef _OMFS_FS_H
2 #define _OMFS_FS_H
3 
4 /* OMFS On-disk structures */
5 
6 #define OMFS_MAGIC 0xC2993D87
7 #define OMFS_IMAGIC 0xD2
8 
9 #define OMFS_DIR 'D'
10 #define OMFS_FILE 'F'
11 #define OMFS_INODE_NORMAL 'e'
12 #define OMFS_INODE_CONTINUATION 'c'
13 #define OMFS_INODE_SYSTEM 's'
14 #define OMFS_NAMELEN 256
15 #define OMFS_DIR_START 0x1b8
16 #define OMFS_EXTENT_START 0x1d0
17 #define OMFS_EXTENT_CONT 0x40
18 #define OMFS_XOR_COUNT 19
19 #define OMFS_MAX_BLOCK_SIZE 8192
20 #define OMFS_MAX_CLUSTER_SIZE 8
21 #define OMFS_MAX_BLOCKS (1ul << 31)
22 
23 struct omfs_super_block {
24 	char s_fill1[256];
25 	__be64 s_root_block;		/* block number of omfs_root_block */
26 	__be64 s_num_blocks;		/* total number of FS blocks */
27 	__be32 s_magic;			/* OMFS_MAGIC */
28 	__be32 s_blocksize;		/* size of a block */
29 	__be32 s_mirrors;		/* # of mirrors of system blocks */
30 	__be32 s_sys_blocksize;		/* size of non-data blocks */
31 };
32 
33 struct omfs_header {
34 	__be64 h_self;			/* FS block where this is located */
35 	__be32 h_body_size;		/* size of useful data after header */
36 	__be16 h_crc;			/* crc-ccitt of body_size bytes */
37 	char h_fill1[2];
38 	u8 h_version;			/* version, always 1 */
39 	char h_type;			/* OMFS_INODE_X */
40 	u8 h_magic;			/* OMFS_IMAGIC */
41 	u8 h_check_xor;			/* XOR of header bytes before this */
42 	__be32 h_fill2;
43 };
44 
45 struct omfs_root_block {
46 	struct omfs_header r_head;	/* header */
47 	__be64 r_fill1;
48 	__be64 r_num_blocks;		/* total number of FS blocks */
49 	__be64 r_root_dir;		/* block # of root directory */
50 	__be64 r_bitmap;		/* block # of free space bitmap */
51 	__be32 r_blocksize;		/* size of a block */
52 	__be32 r_clustersize;		/* size allocated for data blocks */
53 	__be64 r_mirrors;		/* # of mirrors of system blocks */
54 	char r_name[OMFS_NAMELEN];	/* partition label */
55 };
56 
57 struct omfs_inode {
58 	struct omfs_header i_head;	/* header */
59 	__be64 i_parent;		/* parent containing this inode */
60 	__be64 i_sibling;		/* next inode in hash bucket */
61 	__be64 i_ctime;			/* ctime, in milliseconds */
62 	char i_fill1[35];
63 	char i_type;			/* OMFS_[DIR,FILE] */
64 	__be32 i_fill2;
65 	char i_fill3[64];
66 	char i_name[OMFS_NAMELEN];	/* filename */
67 	__be64 i_size;			/* size of file, in bytes */
68 };
69 
70 struct omfs_extent_entry {
71 	__be64 e_cluster;		/* start location of a set of blocks */
72 	__be64 e_blocks;		/* number of blocks after e_cluster */
73 };
74 
75 struct omfs_extent {
76 	__be64 e_next;			/* next extent table location */
77 	__be32 e_extent_count;		/* total # extents in this table */
78 	__be32 e_fill;
79 	struct omfs_extent_entry e_entry;	/* start of extent entries */
80 };
81 
82 #endif
83