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 /* 28 * The uberblock version is incremented whenever an incompatible on-disk 29 * format change is made to the SPA, DMU, or ZAP. 30 * 31 * Note: the first two fields should never be moved. When a storage pool 32 * is opened, the uberblock must be read off the disk before the version 33 * can be checked. If the ub_version field is moved, we may not detect 34 * version mismatch. If the ub_magic field is moved, applications that 35 * expect the magic number in the first word won't work. 36 */ 37 #define UBERBLOCK_MAGIC 0x00bab10c /* oo-ba-bloc! */ 38 #define UBERBLOCK_SHIFT 10 /* up to 1K */ 39 40 struct uberblock { 41 uint64_t ub_magic; /* UBERBLOCK_MAGIC */ 42 uint64_t ub_version; /* ZFS_VERSION */ 43 uint64_t ub_txg; /* txg of last sync */ 44 uint64_t ub_guid_sum; /* sum of all vdev guids */ 45 uint64_t ub_timestamp; /* UTC time of last sync */ 46 blkptr_t ub_rootbp; /* MOS objset_phys_t */ 47 }; 48 49 #endif /* _SYS_UBERBLOCK_IMPL_H */ 50