xref: /illumos-gate/usr/src/uts/common/fs/zfs/uberblock.c (revision 231aab857f14a3e7a0ed5f2879399c3cd6ae92ea)
1fa9e4066Sahrens /*
2fa9e4066Sahrens  * CDDL HEADER START
3fa9e4066Sahrens  *
4fa9e4066Sahrens  * The contents of this file are subject to the terms of the
5ea8dc4b6Seschrock  * Common Development and Distribution License (the "License").
6ea8dc4b6Seschrock  * You may not use this file except in compliance with the License.
7fa9e4066Sahrens  *
8fa9e4066Sahrens  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9fa9e4066Sahrens  * or http://www.opensolaris.org/os/licensing.
10fa9e4066Sahrens  * See the License for the specific language governing permissions
11fa9e4066Sahrens  * and limitations under the License.
12fa9e4066Sahrens  *
13fa9e4066Sahrens  * When distributing Covered Code, include this CDDL HEADER in each
14fa9e4066Sahrens  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15fa9e4066Sahrens  * If applicable, add the following below this CDDL HEADER, with the
16fa9e4066Sahrens  * fields enclosed by brackets "[]" replaced with your own identifying
17fa9e4066Sahrens  * information: Portions Copyright [yyyy] [name of copyright owner]
18fa9e4066Sahrens  *
19fa9e4066Sahrens  * CDDL HEADER END
20fa9e4066Sahrens  */
21fa9e4066Sahrens /*
223f9d6ad7SLin Ling  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23*231aab85SMatthew Ahrens  * Copyright (c) 2013, 2014 by Delphix. All rights reserved.
24fa9e4066Sahrens  */
25fa9e4066Sahrens 
26fa9e4066Sahrens #include <sys/zfs_context.h>
27fa9e4066Sahrens #include <sys/uberblock_impl.h>
28fa9e4066Sahrens #include <sys/vdev_impl.h>
29fa9e4066Sahrens 
30fa9e4066Sahrens int
31fa9e4066Sahrens uberblock_verify(uberblock_t *ub)
32fa9e4066Sahrens {
33fa9e4066Sahrens 	if (ub->ub_magic == BSWAP_64((uint64_t)UBERBLOCK_MAGIC))
34fa9e4066Sahrens 		byteswap_uint64_array(ub, sizeof (uberblock_t));
35fa9e4066Sahrens 
36fa9e4066Sahrens 	if (ub->ub_magic != UBERBLOCK_MAGIC)
37be6fd75aSMatthew Ahrens 		return (SET_ERROR(EINVAL));
38fa9e4066Sahrens 
39fa9e4066Sahrens 	return (0);
40fa9e4066Sahrens }
41fa9e4066Sahrens 
42fa9e4066Sahrens /*
43*231aab85SMatthew Ahrens  * Update the uberblock and return TRUE if anything changed in this
44*231aab85SMatthew Ahrens  * transaction group.
45fa9e4066Sahrens  */
46*231aab85SMatthew Ahrens boolean_t
47fa9e4066Sahrens uberblock_update(uberblock_t *ub, vdev_t *rvd, uint64_t txg)
48fa9e4066Sahrens {
49fa9e4066Sahrens 	ASSERT(ub->ub_txg < txg);
50fa9e4066Sahrens 
51eaca9bbdSeschrock 	/*
52eaca9bbdSeschrock 	 * We explicitly do not set ub_version here, so that older versions
53eaca9bbdSeschrock 	 * continue to be written with the previous uberblock version.
54eaca9bbdSeschrock 	 */
55fa9e4066Sahrens 	ub->ub_magic = UBERBLOCK_MAGIC;
56fa9e4066Sahrens 	ub->ub_txg = txg;
57fa9e4066Sahrens 	ub->ub_guid_sum = rvd->vdev_guid_sum;
58fa9e4066Sahrens 	ub->ub_timestamp = gethrestime_sec();
593f9d6ad7SLin Ling 	ub->ub_software_version = SPA_VERSION;
60fa9e4066Sahrens 
61fa9e4066Sahrens 	return (ub->ub_rootbp.blk_birth == txg);
62fa9e4066Sahrens }
63