xref: /freebsd/sys/contrib/openzfs/module/zfs/uberblock.c (revision bdd1243df58e60e85101c09001d9812a789b6bc4)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or https://opensource.org/licenses/CDDL-1.0.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23  * Copyright (c) 2013, 2017 by Delphix. All rights reserved.
24  */
25 
26 #include <sys/zfs_context.h>
27 #include <sys/uberblock_impl.h>
28 #include <sys/vdev_impl.h>
29 #include <sys/mmp.h>
30 
31 int
32 uberblock_verify(uberblock_t *ub)
33 {
34 	if (ub->ub_magic == BSWAP_64((uint64_t)UBERBLOCK_MAGIC))
35 		byteswap_uint64_array(ub, sizeof (uberblock_t));
36 
37 	if (ub->ub_magic != UBERBLOCK_MAGIC)
38 		return (SET_ERROR(EINVAL));
39 
40 	return (0);
41 }
42 
43 /*
44  * Update the uberblock and return TRUE if anything changed in this
45  * transaction group.
46  */
47 boolean_t
48 uberblock_update(uberblock_t *ub, vdev_t *rvd, uint64_t txg, uint64_t mmp_delay)
49 {
50 	ASSERT(ub->ub_txg < txg);
51 
52 	/*
53 	 * We explicitly do not set ub_version here, so that older versions
54 	 * continue to be written with the previous uberblock version.
55 	 */
56 	ub->ub_magic = UBERBLOCK_MAGIC;
57 	ub->ub_txg = txg;
58 	ub->ub_guid_sum = rvd->vdev_guid_sum;
59 	ub->ub_timestamp = gethrestime_sec();
60 	ub->ub_software_version = SPA_VERSION;
61 	ub->ub_mmp_magic = MMP_MAGIC;
62 	if (spa_multihost(rvd->vdev_spa)) {
63 		ub->ub_mmp_delay = mmp_delay;
64 		ub->ub_mmp_config = MMP_SEQ_SET(0) |
65 		    MMP_INTERVAL_SET(zfs_multihost_interval) |
66 		    MMP_FAIL_INT_SET(zfs_multihost_fail_intervals);
67 	} else {
68 		ub->ub_mmp_delay = 0;
69 		ub->ub_mmp_config = 0;
70 	}
71 	ub->ub_checkpoint_txg = 0;
72 
73 	return (ub->ub_rootbp.blk_birth == txg);
74 }
75