14d3c95f5SJorgen Lundman /* 24d3c95f5SJorgen Lundman * GRUB -- GRand Unified Bootloader 34d3c95f5SJorgen Lundman * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc. 44d3c95f5SJorgen Lundman * 5*1a459660SWolfgang Denk * SPDX-License-Identifier: GPL-2.0+ 64d3c95f5SJorgen Lundman */ 74d3c95f5SJorgen Lundman /* 84d3c95f5SJorgen Lundman * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 94d3c95f5SJorgen Lundman * Use is subject to license terms. 104d3c95f5SJorgen Lundman */ 114d3c95f5SJorgen Lundman 124d3c95f5SJorgen Lundman #ifndef _SYS_UBERBLOCK_IMPL_H 134d3c95f5SJorgen Lundman #define _SYS_UBERBLOCK_IMPL_H 144d3c95f5SJorgen Lundman 154d3c95f5SJorgen Lundman #define UBMAX(a, b) ((a) > (b) ? (a) : (b)) 164d3c95f5SJorgen Lundman 174d3c95f5SJorgen Lundman /* 184d3c95f5SJorgen Lundman * The uberblock version is incremented whenever an incompatible on-disk 194d3c95f5SJorgen Lundman * format change is made to the SPA, DMU, or ZAP. 204d3c95f5SJorgen Lundman * 214d3c95f5SJorgen Lundman * Note: the first two fields should never be moved. When a storage pool 224d3c95f5SJorgen Lundman * is opened, the uberblock must be read off the disk before the version 234d3c95f5SJorgen Lundman * can be checked. If the ub_version field is moved, we may not detect 244d3c95f5SJorgen Lundman * version mismatch. If the ub_magic field is moved, applications that 254d3c95f5SJorgen Lundman * expect the magic number in the first word won't work. 264d3c95f5SJorgen Lundman */ 274d3c95f5SJorgen Lundman #define UBERBLOCK_MAGIC 0x00bab10c /* oo-ba-bloc! */ 284d3c95f5SJorgen Lundman #define UBERBLOCK_SHIFT 10 /* up to 1K */ 294d3c95f5SJorgen Lundman 304d3c95f5SJorgen Lundman typedef struct uberblock { 314d3c95f5SJorgen Lundman uint64_t ub_magic; /* UBERBLOCK_MAGIC */ 324d3c95f5SJorgen Lundman uint64_t ub_version; /* ZFS_VERSION */ 334d3c95f5SJorgen Lundman uint64_t ub_txg; /* txg of last sync */ 344d3c95f5SJorgen Lundman uint64_t ub_guid_sum; /* sum of all vdev guids */ 354d3c95f5SJorgen Lundman uint64_t ub_timestamp; /* UTC time of last sync */ 364d3c95f5SJorgen Lundman blkptr_t ub_rootbp; /* MOS objset_phys_t */ 374d3c95f5SJorgen Lundman } uberblock_t; 384d3c95f5SJorgen Lundman 394d3c95f5SJorgen Lundman #define VDEV_UBERBLOCK_SHIFT(as) UBMAX(as, UBERBLOCK_SHIFT) 404d3c95f5SJorgen Lundman #define UBERBLOCK_SIZE(as) (1ULL << VDEV_UBERBLOCK_SHIFT(as)) 414d3c95f5SJorgen Lundman 424d3c95f5SJorgen Lundman /* Number of uberblocks that can fit in the ring at a given ashift */ 434d3c95f5SJorgen Lundman #define UBERBLOCK_COUNT(as) (VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT(as)) 444d3c95f5SJorgen Lundman 454d3c95f5SJorgen Lundman #endif /* _SYS_UBERBLOCK_IMPL_H */ 46