xref: /openbmc/linux/fs/omfs/omfs_fs.h (revision c900529f3d9161bfde5cca0754f83b4d3c3e0220)
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
84