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 #define UBMAX(a, b) ((a) > (b) ? (a) : (b)) 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 42 typedef struct 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 } uberblock_t; 50 51 #define VDEV_UBERBLOCK_SHIFT(as) UBMAX(as, UBERBLOCK_SHIFT) 52 #define UBERBLOCK_SIZE(as) (1ULL << VDEV_UBERBLOCK_SHIFT(as)) 53 54 /* Number of uberblocks that can fit in the ring at a given ashift */ 55 #define UBERBLOCK_COUNT(as) (VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT(as)) 56 57 #endif /* _SYS_UBERBLOCK_IMPL_H */ 58