OpenGrok

Cross Reference: uberblock.c
xref: /onnv/onnv-gate/usr/src/uts/common/fs/zfs/uberblock.c
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      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 http://www.opensolaris.org/os/licensing.
     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  */
     24 
     25 #include <sys/zfs_context.h>
     26 #include <sys/uberblock_impl.h>
     27 #include <sys/vdev_impl.h>
     28 
     29 int
     30 uberblock_verify(uberblock_t *ub)
     31 {
     32 	if (ub->ub_magic == BSWAP_64((uint64_t)UBERBLOCK_MAGIC))
     33 		byteswap_uint64_array(ub, sizeof (uberblock_t));
     34 
     35 	if (ub->ub_magic != UBERBLOCK_MAGIC)
     36 		return (EINVAL);
     37 
     38 	return (0);
     39 }
     40 
     41 /*
     42  * Update the uberblock and return a boolean value indicating whether
     43  * anything changed in this transaction group.
     44  */
     45 int
     46 uberblock_update(uberblock_t *ub, vdev_t *rvd, uint64_t txg)
     47 {
     48 	ASSERT(ub->ub_txg < txg);
     49 
     50 	/*
     51 	 * We explicitly do not set ub_version here, so that older versions
     52 	 * continue to be written with the previous uberblock version.
     53 	 */
     54 	ub->ub_magic = UBERBLOCK_MAGIC;
     55 	ub->ub_txg = txg;
     56 	ub->ub_guid_sum = rvd->vdev_guid_sum;
     57 	ub->ub_timestamp = gethrestime_sec();
     58 	ub->ub_software_version = SPA_VERSION;
     59 
     60 	return (ub->ub_rootbp.blk_birth == txg);
     61 }
     62