/*      

 * gm_reiserfs.c -- gpart ReiserFS guessing module

 *

 * gpart (c) 1999-2001 Michail Brzitwa <mb@ichabod.han.de>

 * Guess PC-type hard disk partitions.

 *

 * gpart is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published

 * by the Free Software Foundation; either version 2, or (at your

 * option) any later version.

 *

 * Created:   21.01.1999 <mb@ichabod.han.de>

 * Modified:  26.12.2000 Francis Devereux <francis@devereux.tc>

 *            Added reiserfs 3.5.28 support.

 * Modified:  10.01.2003 Yury Umanets <umka@namesys.com>

 *            Added reiserfs 3.6.x support.

 *

 */

#include <string.h>

#include <errno.h>

#include "gpart.h"

#include "gm_reiserfs.h"

static const char	rcsid[] = "$Id: gm_reiserfs.c,v 1.5 2003/01/10 16:38:08 mb Exp mb $";

int reiserfs_init(disk_desc *d,g_module *m)

{

	if ((d == 0) || (m == 0))

		return (0);

	m->m_desc = "ReiserFS filesystem";

	return (REISERFS_FIRST_BLOCK * 1024 + SB_V35_SIZE);

}

int reiserfs_term(disk_desc *d)

{

	return (1);

}

int reiserfs_gfun(disk_desc *d,g_module *m)

{

	struct reiserfs_super_block_v35	*sb;

	dos_part_entry			*pt = &m->m_part;

	s64_t				size;

	m->m_guess = GM_NO;

	sb = (struct reiserfs_super_blockv35 *)(d->d_sbuf + REISERFS_FIRST_BLOCK * 1024);

	if (strncmp(sb->s_magic,REISERFS_SUPER_V35_MAGIC,12) == 0 || 

	    strncmp(sb->s_magic,REISERFS_SUPER_V36_MAGIC,12) == 0)

	{

		/*

		 * sanity checks.

		 */

		if (sb->s_block_count < sb->s_free_blocks)

			return (1);

		if (sb->s_block_count < REISERFS_MIN_BLOCK_AMOUNT)

			return (1);

		if ((sb->s_state != REISERFS_VALID_FS) &&

		    (sb->s_state != REISERFS_ERROR_FS))

			return (1);

		if (sb->s_oid_maxsize % 2) /* must be even */

			return (1);

		if (sb->s_oid_maxsize < sb->s_oid_cursize)

			return (1);

		if ((sb->s_blocksize != 4096) && (sb->s_blocksize != 8192))

			return (1);

		/*

		 * ok.

		 */

		m->m_guess = GM_YES;

		pt->p_start = d->d_nsb;

		size = sb->s_block_count; size *= sb->s_blocksize; size /= d->d_ssize;

		pt->p_size = (unsigned long)size;

		pt->p_typ = 0x83;

	}

	return (1);

}

/*

 * gm_reiserfs.h -- gpart ReiserFS guessing module header

 * 

 * gpart (c) 1999-2001 Michail Brzitwa <mb@ichabod.han.de>

 * Guess PC-type hard disk partitions.

 *

 * gpart is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published

 * by the Free Software Foundation; either version 2, or (at your

 * option) any later version.

 *

 * Created:   21.01.1999 <mb@ichabod.han.de>

 * Modified:  26.12.2000 Francis Devereux <francis@devereux.tc>

 *            Update support reiserfs version 3.5.28

 * Modified:  10.01.2003 Yury Umanets <umka@namesys.com>

 *            Added reiserfs 3.6.x support.

 *

 */

#ifndef _GM_reiserfs_H

#define _GM_reiserfs_H

/* imported from asm/types.h */

typedef __signed__ char __s8;

typedef unsigned char __u8;

typedef __signed__ short __s16;

typedef unsigned short __u16;

typedef __signed__ int __s32;

typedef unsigned int __u32;

/*

 * taken from ReiserFS v3.5.28, v3.6.x. Reiserfs Copyright 1996-2000 Hans Reiser

 */

#define REISERFS_SUPER_V35_MAGIC	"ReIsErFs"

#define REISERFS_SUPER_V36_MAGIC	"ReIsEr2Fs"

#define REISERFS_FIRST_BLOCK		64

#define REISERFS_VALID_FS		1

#define REISERFS_ERROR_FS		2

#define REISERFS_MIN_BLOCK_AMOUNT	100

struct reiserfs_super_block_v35

{

	__u32 s_block_count;		/* blocks count         */

	__u32 s_free_blocks;		/* free blocks count    */

	__u32 s_root_block;		/* root block number    */

	__u32 s_journal_block;		/* journal block number    */

	__u32 s_journal_dev;		/* journal device number  */

	__u32 s_orig_journal_size;	/* size of the journal on FS creation.  used to make sure they don't overflow it */

	__u32 s_journal_trans_max;	/* max number of blocks in a transaction.  */

	__u32 s_journal_block_count;	/* total size of the journal. can change over time  */

	__u32 s_journal_max_batch;	/* max number of blocks to batch into a trans */

	__u32 s_journal_max_commit_age;	/* in seconds, how old can an async commit be */

	__u32 s_journal_max_trans_age;	/* in seconds, how old can a transaction be */

	__u16 s_blocksize;		/* block size           */

	__u16 s_oid_maxsize;		/* max size of object id array, see get_objectid() commentary  */

	__u16 s_oid_cursize;		/* current size of object id array */

	__u16 s_state;			/* valid or error       */

	char s_magic[12];		/* reiserfs magic string indicates that file system is reiserfs */

	__u32 s_hash_function_code;	/* indicate, what hash fuction is being use to sort names in a directory*/

	__u16 s_tree_height;		/* height of disk tree */

	__u16 s_bmap_nr;		/* amount of bitmap blocks needed to address each block of file system */

	__u16 s_reserved;

};

#define SB_V35_SIZE (sizeof(struct reiserfs_super_block_v35))

struct reiserfs_super_block_v36 {

	struct reiserfs_super_block_v35 s_v35;

	__u32 s_inode_generation; 

	__u32 s_flags;

	char s_uuid[16];

	char s_label[16];

	char s_unused[88];

};

#define SB_V36_SIZE (sizeof(struct reiserfs_super_block_v36))

#endif /* _GM_REISERFS_H */