omfs: define filesystem structures

#ifndef _OMFS_H

#define _OMFS_H

#include <linux/module.h>

#include <linux/fs.h>

#include "omfs_fs.h"

/* In-memory structures */

struct omfs_sb_info {

	u64 s_num_blocks;

	u64 s_bitmap_ino;

	u64 s_root_ino;

	u32 s_blocksize;

	u32 s_mirrors;

	u32 s_sys_blocksize;

	u32 s_clustersize;

	int s_block_shift;

	unsigned long **s_imap;

	int s_imap_size;

	struct mutex s_bitmap_lock;

	int s_uid;

	int s_gid;

	int s_dmask;

	int s_fmask;

};

/* convert a cluster number to a scaled block number */

static inline sector_t clus_to_blk(struct omfs_sb_info *sbi, sector_t block)

{

	return block << sbi->s_block_shift;

}

static inline struct omfs_sb_info *OMFS_SB(struct super_block *sb)

{

	return sb->s_fs_info;

}

/* bitmap.c */

extern unsigned long omfs_count_free(struct super_block *sb);

extern int omfs_allocate_block(struct super_block *sb, u64 block);

extern int omfs_allocate_range(struct super_block *sb, int min_request,

			int max_request, u64 *return_block, int *return_size);

extern int omfs_clear_range(struct super_block *sb, u64 block, int count);

/* dir.c */

extern struct file_operations omfs_dir_operations;

extern struct inode_operations omfs_dir_inops;

extern int omfs_make_empty(struct inode *inode, struct super_block *sb);

extern int omfs_is_bad(struct omfs_sb_info *sbi, struct omfs_header *header,

			u64 fsblock);

/* file.c */

extern struct file_operations omfs_file_operations;

extern struct inode_operations omfs_file_inops;

extern struct address_space_operations omfs_aops;

extern void omfs_make_empty_table(struct buffer_head *bh, int offset);

extern int omfs_shrink_inode(struct inode *inode);

/* inode.c */

extern struct inode *omfs_iget(struct super_block *sb, ino_t inode);

extern struct inode *omfs_new_inode(struct inode *dir, int mode);

extern int omfs_reserve_block(struct super_block *sb, sector_t block);

extern int omfs_find_empty_block(struct super_block *sb, int mode, ino_t *ino);

extern int omfs_sync_inode(struct inode *inode);

#endif

#ifndef _OMFS_FS_H

#define _OMFS_FS_H

/* OMFS On-disk structures */

#define OMFS_MAGIC 0xC2993D87

#define OMFS_IMAGIC 0xD2

#define OMFS_DIR 'D'

#define OMFS_FILE 'F'

#define OMFS_INODE_NORMAL 'e'

#define OMFS_INODE_CONTINUATION 'c'

#define OMFS_INODE_SYSTEM 's'

#define OMFS_NAMELEN 256

#define OMFS_DIR_START 0x1b8

#define OMFS_EXTENT_START 0x1d0

#define OMFS_EXTENT_CONT 0x40

#define OMFS_XOR_COUNT 19

#define OMFS_MAX_BLOCK_SIZE 8192

struct omfs_super_block {

	char s_fill1[256];

	__be64 s_root_block;		/* block number of omfs_root_block */

	__be64 s_num_blocks;		/* total number of FS blocks */

	__be32 s_magic;			/* OMFS_MAGIC */

	__be32 s_blocksize;		/* size of a block */

	__be32 s_mirrors;		/* # of mirrors of system blocks */

	__be32 s_sys_blocksize;		/* size of non-data blocks */

};

struct omfs_header {

	__be64 h_self;			/* FS block where this is located */

	__be32 h_body_size;		/* size of useful data after header */

	__be16 h_crc;			/* crc-ccitt of body_size bytes */

	char h_fill1[2];

	u8 h_version;			/* version, always 1 */

	char h_type;			/* OMFS_INODE_X */

	u8 h_magic;			/* OMFS_IMAGIC */

	u8 h_check_xor;			/* XOR of header bytes before this */

	__be32 h_fill2;

};

struct omfs_root_block {

	struct omfs_header r_head;	/* header */

	__be64 r_fill1;

	__be64 r_num_blocks;		/* total number of FS blocks */

	__be64 r_root_dir;		/* block # of root directory */

	__be64 r_bitmap;		/* block # of free space bitmap */

	__be32 r_blocksize;		/* size of a block */

	__be32 r_clustersize;		/* size allocated for data blocks */

	__be64 r_mirrors;		/* # of mirrors of system blocks */

	char r_name[OMFS_NAMELEN];	/* partition label */

};

struct omfs_inode {

	struct omfs_header i_head;	/* header */

	__be64 i_parent;		/* parent containing this inode */

	__be64 i_sibling;		/* next inode in hash bucket */

	__be64 i_ctime;			/* ctime, in milliseconds */

	char i_fill1[35];

	char i_type;			/* OMFS_[DIR,FILE] */

	__be32 i_fill2;

	char i_fill3[64];

	char i_name[OMFS_NAMELEN];	/* filename */

	__be64 i_size;			/* size of file, in bytes */

};

struct omfs_extent_entry {

	__be64 e_cluster;		/* start location of a set of blocks */

	__be64 e_blocks;		/* number of blocks after e_cluster */

};

struct omfs_extent {

	__be64 e_next;			/* next extent table location */

	__be32 e_extent_count;		/* total # extents in this table */

	__be32 e_fill;

	struct omfs_extent_entry e_entry;	/* start of extent entries */

};

#endif