efs_fs_sb.h

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/*
 * efs_fs_sb.h
 *
 * Copyright (c) 1999 Al Smith
 *
 * Portions derived from IRIX header files (c) 1988 Silicon Graphics
 */

#ifndef __EFS_FS_SB_H__
#define __EFS_FS_SB_H__

#include <linux/types.h>
#include <linux/magic.h>

/* EFS superblock magic numbers */
#define EFS_MAGIC   0x072959
#define EFS_NEWMAGIC    0x07295a

#define IS_EFS_MAGIC(x) ((x == EFS_MAGIC) || (x == EFS_NEWMAGIC))

#define EFS_SUPER       1
#define EFS_ROOTINODE       2

/* efs superblock on disk */
struct efs_super {
    __be32      fs_size;        /* size of filesystem, in sectors */
    __be32      fs_firstcg;     /* bb offset to first cg */
    __be32      fs_cgfsize;     /* size of cylinder group in bb's */
    __be16      fs_cgisize;     /* bb's of inodes per cylinder group */
    __be16      fs_sectors;     /* sectors per track */
    __be16      fs_heads;       /* heads per cylinder */
    __be16      fs_ncg;         /* # of cylinder groups in filesystem */
    __be16      fs_dirty;       /* fs needs to be fsck'd */
    __be32      fs_time;        /* last super-block update */
    __be32      fs_magic;       /* magic number */
    char        fs_fname[6];    /* file system name */
    char        fs_fpack[6];    /* file system pack name */
    __be32      fs_bmsize;      /* size of bitmap in bytes */
    __be32      fs_tfree;       /* total free data blocks */
    __be32      fs_tinode;      /* total free inodes */
    __be32      fs_bmblock;     /* bitmap location. */
    __be32      fs_replsb;      /* Location of replicated superblock. */
    __be32      fs_lastialloc;  /* last allocated inode */
    char        fs_spare[20];   /* space for expansion - MUST BE ZERO */
    __be32      fs_checksum;    /* checksum of volume portion of fs */
};

/* efs superblock information in memory */
struct efs_sb_info {
    __u32   fs_magic;   /* superblock magic number */
    __u32   fs_start;   /* first block of filesystem */
    __u32   first_block;    /* first data block in filesystem */
    __u32   total_blocks;   /* total number of blocks in filesystem */
    __u32   group_size; /* # of blocks a group consists of */ 
    __u32   data_free;  /* # of free data blocks */
    __u32   inode_free; /* # of free inodes */
    __u16   inode_blocks;   /* # of blocks used for inodes in every grp */
    __u16   total_groups;   /* # of groups */
};

#endif /* __EFS_FS_SB_H__ */