7 files changed, 125 insertions, 24 deletions

diff --git a/cddl/contrib/opensolaris/cmd/zfs/zfs.8 b/cddl/contrib/opensolaris/cmd/zfs/zfs.8
index 9eb30823e6fb..a28abf016057 100644
--- a/cddl/contrib/opensolaris/cmd/zfs/zfs.8
+++ b/cddl/contrib/opensolaris/cmd/zfs/zfs.8
@@ -18,7 +18,7 @@
 .\" information: Portions Copyright [yyyy] [name of copyright owner]
 .\"
 .\" Copyright (c) 2010, Sun Microsystems, Inc. All Rights Reserved.
-.\" Copyright (c) 2013 by Delphix. All rights reserved.
+.\" Copyright (c) 2014 by Delphix. All rights reserved.
 .\" Copyright (c) 2011, Pawel Jakub Dawidek <pjd@FreeBSD.org>
 .\" Copyright (c) 2012, Glen Barber <gjb@FreeBSD.org>
 .\" Copyright (c) 2012, Bryan Drewery <bdrewery@FreeBSD.org>
@@ -30,7 +30,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd April 23, 2014
+.Dd May 27, 2014
 .Dt ZFS 8
 .Os
 .Sh NAME
@@ -1193,6 +1193,53 @@ affects only files created afterward; existing files are unaffected.
 .Pp
 This property can also be referred to by its shortened column name,
 .Sy recsize .
+.It Sy redundant_metadata Ns = Ns Cm all | most
+Controls what types of metadata are stored redundantly.
+ZFS stores an extra copy of metadata, so that if a single block is corrupted,
+the amount of user data lost is limited.
+This extra copy is in addition to any redundancy provided at the pool level
+.Pq e.g. by mirroring or RAID-Z ,
+and is in addition to an extra copy specified by the
+.Sy copies
+property
+.Pq up to a total of 3 copies .
+For example if the pool is mirrored,
+.Cm copies Ns = Ns Ar 2 ,
+and
+.Cm redundant_metadata Ns = Ns Ar most ,
+then ZFS
+stores 6 copies of most metadata, and 4 copies of data and some
+metadata.
+.Pp
+When set to
+.Cm all ,
+ZFS stores an extra copy of all metadata.
+If a
+single on-disk block is corrupt, at worst a single block of user data
+.Po which is
+.Cm recordsize
+bytes long
+can be lost.
+.Pc
+.Pp
+When set to
+.Cm most ,
+ZFS stores an extra copy of most types of
+metadata.
+This can improve performance of random writes, because less
+metadata must be written.
+In practice, at worst about 100 blocks
+.Po of
+.Cm recordsize
+bytes each
+.Pc
+of user data can be lost if a single
+on-disk block is corrupt.
+The exact behavior of which metadata blocks
+are stored redundantly may change in future releases.
+.Pp
+The default value is
+.Cm all .
 .It Sy refquota Ns = Ns Ar size | Cm none
 Limits the amount of space a dataset can consume. This property enforces a hard
 limit on the amount of space used. This hard limit does not include space used
diff --git a/sys/cddl/contrib/opensolaris/common/zfs/zfs_prop.c b/sys/cddl/contrib/opensolaris/common/zfs/zfs_prop.c
index 141e22663679..b345206a4a1c 100644
--- a/sys/cddl/contrib/opensolaris/common/zfs/zfs_prop.c
+++ b/sys/cddl/contrib/opensolaris/common/zfs/zfs_prop.c
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2013 by Delphix. All rights reserved.
+ * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
  * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
  * Copyright (c) 2013, Joyent, Inc. All rights reserved.
  */
@@ -206,7 +206,18 @@ zfs_prop_init(void)
 		{ NULL }
 	};
 
+	static zprop_index_t redundant_metadata_table[] = {
+		{ "all",	ZFS_REDUNDANT_METADATA_ALL },
+		{ "most",	ZFS_REDUNDANT_METADATA_MOST },
+		{ NULL }
+	};
+
 	/* inherit index properties */
+	zprop_register_index(ZFS_PROP_REDUNDANT_METADATA, "redundant_metadata",
+	    ZFS_REDUNDANT_METADATA_ALL,
+	    PROP_INHERIT, ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME,
+	    "all | most", "REDUND_MD",
+	    redundant_metadata_table);
 	zprop_register_index(ZFS_PROP_SYNC, "sync", ZFS_SYNC_STANDARD,
 	    PROP_INHERIT, ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME,
 	    "standard | always | disabled", "SYNC",
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c
index 7da25c7eed90..4aa1c88d0a1d 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2013 by Delphix. All rights reserved.
+ * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
  */
 /* Copyright (c) 2013 by Saso Kiselkov. All rights reserved. */
 /* Copyright (c) 2013, Joyent, Inc. All rights reserved. */
@@ -1630,6 +1630,12 @@ TUNABLE_INT("vfs.zfs.mdcomp_disable", &zfs_mdcomp_disable);
 SYSCTL_INT(_vfs_zfs, OID_AUTO, mdcomp_disable, CTLFLAG_RW,
     &zfs_mdcomp_disable, 0, "Disable metadata compression");
 
+/*
+ * When the "redundant_metadata" property is set to "most", only indirect
+ * blocks of this level and higher will have an additional ditto block.
+ */
+int zfs_redundant_metadata_most_ditto_level = 2;
+
 void
 dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
 {
@@ -1669,6 +1675,13 @@ dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
 		if (zio_checksum_table[checksum].ci_correctable < 1 ||
 		    zio_checksum_table[checksum].ci_eck)
 			checksum = ZIO_CHECKSUM_FLETCHER_4;
+
+		if (os->os_redundant_metadata == ZFS_REDUNDANT_METADATA_ALL ||
+		    (os->os_redundant_metadata ==
+		    ZFS_REDUNDANT_METADATA_MOST &&
+		    (level >= zfs_redundant_metadata_most_ditto_level ||
+		    DMU_OT_IS_METADATA(type) || (wp & WP_SPILL))))
+			copies++;
 	} else if (wp & WP_NOFILL) {
 		ASSERT(level == 0);
 
@@ -1716,7 +1729,7 @@ dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
 	zp->zp_compress = compress;
 	zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type;
 	zp->zp_level = level;
-	zp->zp_copies = MIN(copies + ismd, spa_max_replication(os->os_spa));
+	zp->zp_copies = MIN(copies, spa_max_replication(os->os_spa));
 	zp->zp_dedup = dedup;
 	zp->zp_dedup_verify = dedup && dedup_verify;
 	zp->zp_nopwrite = nopwrite;
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c
index 0c4fe26e3ac9..ef82f17683f6 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_objset.c
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2013 by Delphix. All rights reserved.
+ * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
  * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
  * Copyright (c) 2013, Joyent, Inc. All rights reserved.
  */
@@ -115,13 +115,13 @@ dmu_objset_id(objset_t *os)
 	return (ds ? ds->ds_object : 0);
 }
 
-uint64_t
+zfs_sync_type_t
 dmu_objset_syncprop(objset_t *os)
 {
 	return (os->os_sync);
 }
 
-uint64_t
+zfs_logbias_op_t
 dmu_objset_logbias(objset_t *os)
 {
 	return (os->os_logbias);
@@ -230,6 +230,20 @@ sync_changed_cb(void *arg, uint64_t newval)
 }
 
 static void
+redundant_metadata_changed_cb(void *arg, uint64_t newval)
+{
+	objset_t *os = arg;
+
+	/*
+	 * Inheritance and range checking should have been done by now.
+	 */
+	ASSERT(newval == ZFS_REDUNDANT_METADATA_ALL ||
+	    newval == ZFS_REDUNDANT_METADATA_MOST);
+
+	os->os_redundant_metadata = newval;
+}
+
+static void
 logbias_changed_cb(void *arg, uint64_t newval)
 {
 	objset_t *os = arg;
@@ -364,6 +378,12 @@ dmu_objset_open_impl(spa_t *spa, dsl_dataset_t *ds, blkptr_t *bp,
 				    zfs_prop_to_name(ZFS_PROP_SYNC),
 				    sync_changed_cb, os);
 			}
+			if (err == 0) {
+				err = dsl_prop_register(ds,
+				    zfs_prop_to_name(
+				    ZFS_PROP_REDUNDANT_METADATA),
+				    redundant_metadata_changed_cb, os);
+			}
 		}
 		if (err != 0) {
 			VERIFY(arc_buf_remove_ref(os->os_phys_buf,
@@ -377,9 +397,9 @@ dmu_objset_open_impl(spa_t *spa, dsl_dataset_t *ds, blkptr_t *bp,
 		os->os_compress = ZIO_COMPRESS_LZJB;
 		os->os_copies = spa_max_replication(spa);
 		os->os_dedup_checksum = ZIO_CHECKSUM_OFF;
-		os->os_dedup_verify = 0;
-		os->os_logbias = 0;
-		os->os_sync = 0;
+		os->os_dedup_verify = B_FALSE;
+		os->os_logbias = ZFS_LOGBIAS_LATENCY;
+		os->os_sync = ZFS_SYNC_STANDARD;
 		os->os_primary_cache = ZFS_CACHE_ALL;
 		os->os_secondary_cache = ZFS_CACHE_ALL;
 	}
@@ -622,6 +642,9 @@ dmu_objset_evict(objset_t *os)
 			VERIFY0(dsl_prop_unregister(ds,
 			    zfs_prop_to_name(ZFS_PROP_SYNC),
 			    sync_changed_cb, os));
+			VERIFY0(dsl_prop_unregister(ds,
+			    zfs_prop_to_name(ZFS_PROP_REDUNDANT_METADATA),
+			    redundant_metadata_changed_cb, os));
 		}
 		VERIFY0(dsl_prop_unregister(ds,
 		    zfs_prop_to_name(ZFS_PROP_PRIMARYCACHE),
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h
index 35f94d239bb0..e359a83e2194 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu.h
@@ -21,7 +21,7 @@
 
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2013 by Delphix. All rights reserved.
+ * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
  * Copyright (c) 2012, Joyent, Inc. All rights reserved.
  * Copyright 2013 DEY Storage Systems, Inc.
@@ -746,8 +746,8 @@ extern struct dsl_dataset *dmu_objset_ds(objset_t *os);
 extern void dmu_objset_name(objset_t *os, char *buf);
 extern dmu_objset_type_t dmu_objset_type(objset_t *os);
 extern uint64_t dmu_objset_id(objset_t *os);
-extern uint64_t dmu_objset_syncprop(objset_t *os);
-extern uint64_t dmu_objset_logbias(objset_t *os);
+extern zfs_sync_type_t dmu_objset_syncprop(objset_t *os);
+extern zfs_logbias_op_t dmu_objset_logbias(objset_t *os);
 extern int dmu_snapshot_list_next(objset_t *os, int namelen, char *name,
     uint64_t *id, uint64_t *offp, boolean_t *case_conflict);
 extern int dmu_snapshot_realname(objset_t *os, char *name, char *real,
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_objset.h b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_objset.h
index df8f03103e32..23d88fd048bd 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_objset.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/sys/dmu_objset.h
@@ -20,7 +20,7 @@
  */
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2012 by Delphix. All rights reserved.
+ * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
  * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
  */
 
@@ -85,15 +85,16 @@ struct objset {
 	zilog_t *os_zil;
 
 	/* can change, under dsl_dir's locks: */
-	uint8_t os_checksum;
-	uint8_t os_compress;
+	enum zio_checksum os_checksum;
+	enum zio_compress os_compress;
 	uint8_t os_copies;
-	uint8_t os_dedup_checksum;
-	uint8_t os_dedup_verify;
-	uint8_t os_logbias;
-	uint8_t os_primary_cache;
-	uint8_t os_secondary_cache;
-	uint8_t os_sync;
+	enum zio_checksum os_dedup_checksum;
+	boolean_t os_dedup_verify;
+	zfs_logbias_op_t os_logbias;
+	zfs_cache_type_t os_primary_cache;
+	zfs_cache_type_t os_secondary_cache;
+	zfs_sync_type_t os_sync;
+	zfs_redundant_metadata_type_t os_redundant_metadata;
 
 	/* no lock needed: */
 	struct dmu_tx *os_synctx; /* XXX sketchy */
diff --git a/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h b/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h
index 87cb82eab9df..ef63a575e438 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/sys/fs/zfs.h
@@ -21,7 +21,7 @@
 
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2013 by Delphix. All rights reserved.
+ * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  * Copyright (c) 2013, Joyent, Inc. All rights reserved.
  * Copyright (c) 2012, Martin Matuska <mm@FreeBSD.org>. All rights reserved.
@@ -150,6 +150,7 @@ typedef enum {
 	ZFS_PROP_SNAPSHOT_LIMIT,
 	ZFS_PROP_FILESYSTEM_COUNT,
 	ZFS_PROP_SNAPSHOT_COUNT,
+	ZFS_PROP_REDUNDANT_METADATA,
 	ZFS_NUM_PROPS
 } zfs_prop_t;
 
@@ -349,6 +350,11 @@ typedef enum {
 	ZFS_VOLMODE_NONE = 3
 } zfs_volmode_t;
 
+typedef enum {
+	ZFS_REDUNDANT_METADATA_ALL,
+	ZFS_REDUNDANT_METADATA_MOST
+} zfs_redundant_metadata_type_t;
+
 /*
  * On-disk version number.
  */