1/*
2 *  GRUB  --  GRand Unified Bootloader
3 *  Copyright (C) 1999,2000,2001,2002,2003,2004  Free Software Foundation, Inc.
4 *
5 *  This program is free software; you can redistribute it and/or modify
6 *  it under the terms of the GNU General Public License as published by
7 *  the Free Software Foundation; either version 2 of the License, or
8 *  (at your option) any later version.
9 *
10 *  This program is distributed in the hope that it will be useful,
11 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 *  GNU General Public License for more details.
14 *
15 *  You should have received a copy of the GNU General Public License
16 *  along with this program; if not, write to the Free Software
17 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19/*
20 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
21 * Use is subject to license terms.
22 */
23
24#ifndef _SYS_UBERBLOCK_IMPL_H
25#define	_SYS_UBERBLOCK_IMPL_H
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29/*
30 * The uberblock version is incremented whenever an incompatible on-disk
31 * format change is made to the SPA, DMU, or ZAP.
32 *
33 * Note: the first two fields should never be moved.  When a storage pool
34 * is opened, the uberblock must be read off the disk before the version
35 * can be checked.  If the ub_version field is moved, we may not detect
36 * version mismatch.  If the ub_magic field is moved, applications that
37 * expect the magic number in the first word won't work.
38 */
39#define	UBERBLOCK_MAGIC		0x00bab10c		/* oo-ba-bloc!	*/
40#define	UBERBLOCK_SHIFT		10			/* up to 1K	*/
41
42struct uberblock {
43	uint64_t	ub_magic;	/* UBERBLOCK_MAGIC		*/
44	uint64_t	ub_version;	/* ZFS_VERSION			*/
45	uint64_t	ub_txg;		/* txg of last sync		*/
46	uint64_t	ub_guid_sum;	/* sum of all vdev guids	*/
47	uint64_t	ub_timestamp;	/* UTC time of last sync	*/
48	blkptr_t	ub_rootbp;	/* MOS objset_phys_t		*/
49};
50
51#endif	/* _SYS_UBERBLOCK_IMPL_H */
52