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Diffstat (limited to 'include/zfs/uberblock_impl.h')
| -rw-r--r-- | include/zfs/uberblock_impl.h | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/include/zfs/uberblock_impl.h b/include/zfs/uberblock_impl.h new file mode 100644 index 000000000..806da9585 --- /dev/null +++ b/include/zfs/uberblock_impl.h @@ -0,0 +1,57 @@ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc. + * + * This program 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 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ +/* + * Copyright 2007 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#ifndef _SYS_UBERBLOCK_IMPL_H +#define _SYS_UBERBLOCK_IMPL_H + +#define UBMAX(a, b) ((a) > (b) ? (a) : (b)) + +/* + * The uberblock version is incremented whenever an incompatible on-disk + * format change is made to the SPA, DMU, or ZAP. + * + * Note: the first two fields should never be moved. When a storage pool + * is opened, the uberblock must be read off the disk before the version + * can be checked. If the ub_version field is moved, we may not detect + * version mismatch. If the ub_magic field is moved, applications that + * expect the magic number in the first word won't work. + */ +#define UBERBLOCK_MAGIC 0x00bab10c /* oo-ba-bloc! */ +#define UBERBLOCK_SHIFT 10 /* up to 1K */ + +typedef struct uberblock { + uint64_t ub_magic; /* UBERBLOCK_MAGIC */ + uint64_t ub_version; /* ZFS_VERSION */ + uint64_t ub_txg; /* txg of last sync */ + uint64_t ub_guid_sum; /* sum of all vdev guids */ + uint64_t ub_timestamp; /* UTC time of last sync */ + blkptr_t ub_rootbp; /* MOS objset_phys_t */ +} uberblock_t; + +#define VDEV_UBERBLOCK_SHIFT(as) UBMAX(as, UBERBLOCK_SHIFT) +#define UBERBLOCK_SIZE(as) (1ULL << VDEV_UBERBLOCK_SHIFT(as)) + +/* Number of uberblocks that can fit in the ring at a given ashift */ +#define UBERBLOCK_COUNT(as) (VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT(as)) + +#endif /* _SYS_UBERBLOCK_IMPL_H */ |