1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
|
/* SPDX-License-Identifier: GPL-2.0+ */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc.
*/
/*
* 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 */
|