svn commit: r323758 - stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys

[Andriy Gapon]

Author: avg
Date: Tue Sep 19 09:23:39 2017
New Revision: 323758
URL: https://svnweb.freebsd.org/changeset/base/323758

Log:
  MFC r322241: MFV r322240: 8491 uberblock on-disk padding to reserve space for smoothly merging zpool checkpoint & MMP in ZFS
  
  illumos/illumos-gate at 79c2b812ee2010ebf20fdd92dc5f06b59000a94c
  https://github.com/illumos/illumos-gate/commit/79c2b812ee2010ebf20fdd92dc5f06b59000a94c
  
  https://www.illumos.org/issues/8491
    The zpool checkpoint feature in DxOS added a new field in the uberblock.
    The Multi-Modifier Protection Pull Request from ZoL adds two new fields in the
    uberblock (Reference: https://github.com/zfsonlinux/zfs/pull/6279).
    As these two changes come from two different sources and once upstreamed and
    deployed will introduce an incompatibility with each other we want
    to upstream a change that will reserve the padding for both of them so
    integration goes smoothly and everyone gets both features.
  
  Reviewed by: Matthew Ahrens <mahrens at delphix.com>
  Reviewed by: Brian Behlendorf <behlendorf1 at llnl.gov>
  Reviewed by: Olaf Faaland <faaland1 at llnl.gov>
  Approved by: Gordon Ross <gwr at nexenta.com>
  Author: Serapheim Dimitropoulos <serapheim at delphix.com>

Modified:
  stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/uberblock_impl.h
Directory Properties:
  stable/11/   (props changed)

Modified: stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/uberblock_impl.h
==============================================================================
--- stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/uberblock_impl.h	Tue Sep 19 09:19:19 2017	(r323757)
+++ stable/11/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/uberblock_impl.h	Tue Sep 19 09:23:39 2017	(r323758)
@@ -20,6 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017 by Delphix. All rights reserved.
  */
 
 #ifndef _SYS_UBERBLOCK_IMPL_H
@@ -54,6 +55,12 @@ struct uberblock {
 
 	/* highest SPA_VERSION supported by software that wrote this txg */
 	uint64_t	ub_software_version;
+
+	/* These fields are reserved for features that are under development: */
+	uint64_t	ub_mmp_magic;
+	uint64_t	ub_mmp_delay;
+	uint64_t	ub_mmp_seq;
+	uint64_t	ub_checkpoint_txg;
 };
 
 #ifdef	__cplusplus