Create zap for root vdev

And add it to the AVZ, this is not backwards compatible with older pools
due to an assertion in spa_sync() that verifies the number of ZAPs of
all vdevs matches the number of ZAPs in the AVZ.

Granted, the assertion only applies to #DEBUG builds - still, a feature
flag is introduced to avoid the assertion, com.klarasystems:vdev_zaps_v2

Notably, this allows to get/set properties on the root vdev:

    % zpool set user:prop=value <pool> root-0

Before this commit, it was already possible to get/set properties on
top-level vdevs with the syntax <type>-<vdev_id> (e.g. mirror-0):

    % zpool set user:prop=value <pool> mirror-0

This syntax also applies to the root vdev as it is is of type 'root'
with a vdev_id of 0, root-0. The keyword 'root' as an alias for
'root-0'.

The following tests have been added:

    - zpool get all properties from root vdev
    - zpool set a property on root vdev
    - verify root vdev ZAP is created

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Rob Wing <rob.wing@klarasystems.com>
Sponsored-by: Seagate Technology
Submitted-by: Klara, Inc.
Closes #14405

tests/zfs-tests/tests/Makefile.am

@@ -178,6 +178,7 @@ nobase_dist_datadir_zfs_tests_tests_DATA += \
 	functional/cli_root/zpool_expand/zpool_expand.cfg \
 	functional/cli_root/zpool_export/zpool_export.cfg \
 	functional/cli_root/zpool_export/zpool_export.kshlib \
+	functional/cli_root/zpool_get/vdev_get.cfg \
 	functional/cli_root/zpool_get/zpool_get.cfg \
 	functional/cli_root/zpool_get/zpool_get_parsable.cfg \
 	functional/cli_root/zpool_import/blockfiles/cryptv0.dat.bz2 \
@@ -1032,6 +1033,7 @@ nobase_dist_datadir_zfs_tests_tests_SCRIPTS += \
 	functional/cli_root/zpool_export/zpool_export_004_pos.ksh \
 	functional/cli_root/zpool_get/cleanup.ksh \
 	functional/cli_root/zpool_get/setup.ksh \
+	functional/cli_root/zpool_get/vdev_get_001_pos.ksh \
 	functional/cli_root/zpool_get/zpool_get_001_pos.ksh \
 	functional/cli_root/zpool_get/zpool_get_002_pos.ksh \
 	functional/cli_root/zpool_get/zpool_get_003_pos.ksh \
@@ -1146,6 +1148,7 @@ nobase_dist_datadir_zfs_tests_tests_SCRIPTS += \
 	functional/cli_root/zpool_set/cleanup.ksh \
 	functional/cli_root/zpool_set/setup.ksh \
 	functional/cli_root/zpool/setup.ksh \
+	functional/cli_root/zpool_set/vdev_set_001_pos.ksh \
 	functional/cli_root/zpool_set/zpool_set_001_pos.ksh \
 	functional/cli_root/zpool_set/zpool_set_002_neg.ksh \
 	functional/cli_root/zpool_set/zpool_set_003_neg.ksh \

tests/zfs-tests/tests/functional/cli_root/zpool_get/vdev_get.cfg

@@ -0,0 +1,73 @@
+#
+# CDDL HEADER START
+#
+# The contents of this file are subject to the terms of the
+# Common Development and Distribution License (the "License").
+# You may not use this file except in compliance with the License.
+#
+# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+# or https://opensource.org/licenses/CDDL-1.0.
+# See the License for the specific language governing permissions
+# and limitations under the License.
+#
+# When distributing Covered Code, include this CDDL HEADER in each
+# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+# If applicable, add the following below this CDDL HEADER, with the
+# fields enclosed by brackets "[]" replaced with your own identifying
+# information: Portions Copyright [yyyy] [name of copyright owner]
+#
+# CDDL HEADER END
+#
+
+#
+# Copyright (c) 2022, Klara Inc.
+#
+
+# Set the expected properties of a vdev
+typeset -a properties=(
+    capacity
+    state
+    guid
+    asize
+    psize
+    ashift
+    size
+    free
+    allocated
+    comment
+    expandsize
+    fragmentation
+    bootsize
+    parity
+    path
+    devid
+    physpath
+    encpath
+    fru
+    parent
+    children
+    numchildren
+    read_errors
+    write_errors
+    checksum_errors
+    initialize_errors
+    null_ops
+    read_ops
+    write_ops
+    free_ops
+    claim_ops
+    trim_ops
+    null_bytes
+    read_bytes
+    write_bytes
+    free_bytes
+    claim_bytes
+    trim_bytes
+    removing
+    allocating
+    failfast
+    checksum_n
+    checksum_t
+    io_n
+    io_t
+)

tests/zfs-tests/tests/functional/cli_root/zpool_get/vdev_get_001_pos.ksh

@@ -0,0 +1,62 @@
+#!/bin/ksh -p
+#
+# CDDL HEADER START
+#
+# The contents of this file are subject to the terms of the
+# Common Development and Distribution License (the "License").
+# You may not use this file except in compliance with the License.
+#
+# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+# or https://opensource.org/licenses/CDDL-1.0.
+# See the License for the specific language governing permissions
+# and limitations under the License.
+#
+# When distributing Covered Code, include this CDDL HEADER in each
+# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+# If applicable, add the following below this CDDL HEADER, with the
+# fields enclosed by brackets "[]" replaced with your own identifying
+# information: Portions Copyright [yyyy] [name of copyright owner]
+#
+# CDDL HEADER END
+#
+
+#
+# Copyright (c) 2022, Klara Inc.
+#
+
+. $STF_SUITE/include/libtest.shlib
+. $STF_SUITE/tests/functional/cli_root/zpool_get/vdev_get.cfg
+
+#
+# DESCRIPTION:
+#
+# zpool get <pool> root works as expected
+#
+# STRATEGY:
+#
+# 1. use zpool get to retrieve properties from root vdev
+# 2. verify expected properties match detected properties
+#
+
+log_assert "zpool get all on root vdev"
+
+EXPECT="$(zpool get -H all ${TESTPOOL} root | wc -l)"
+if [ $? -ne 0 ]; then
+    log_fail "cannot retrieve properties from root vdev"
+fi
+
+i=0;
+while [ $i -lt "${#properties[@]}" ]
+do
+	log_must zpool get -H "${properties[$i]}" "$TESTPOOL" root
+	i=$(($i+1))
+done
+
+EXPECT=$((EXPECT))
+if [ $i -gt $EXPECT ]; then
+	log_fail "found vdev properties not in vdev_get.cfg: $i/$EXPECT."
+elif [ $i -lt $EXPECT ]; then
+    log_fail "expected properties not found in vdev_get.cfg: $i/$EXPECT."
+fi
+
+log_pass "zpool get all on root vdev"

tests/zfs-tests/tests/functional/cli_root/zpool_get/zpool_get.cfg

@@ -104,5 +104,6 @@ if is_linux || is_freebsd; then
 	    "feature@head_errlog"
 	    "feature@blake3"
 	    "feature@block_cloning"
+	    "feature@vdev_zaps_v2"
 	)
 fi

tests/zfs-tests/tests/functional/cli_root/zpool_set/vdev_set_001_pos.ksh

@@ -0,0 +1,52 @@
+#!/bin/ksh -p
+#
+# CDDL HEADER START
+#
+# The contents of this file are subject to the terms of the
+# Common Development and Distribution License (the "License").
+# You may not use this file except in compliance with the License.
+#
+# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+# or https://opensource.org/licenses/CDDL-1.0.
+# See the License for the specific language governing permissions
+# and limitations under the License.
+#
+# When distributing Covered Code, include this CDDL HEADER in each
+# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+# If applicable, add the following below this CDDL HEADER, with the
+# fields enclosed by brackets "[]" replaced with your own identifying
+# information: Portions Copyright [yyyy] [name of copyright owner]
+#
+# CDDL HEADER END
+#
+
+#
+# Copyright (c) 2022, Klara Inc.
+#
+
+. $STF_SUITE/include/libtest.shlib
+
+#
+# DESCRIPTION:
+#
+# zpool set comment property on root vdev
+#
+# STRATEGY:
+#	1. set a property on root vdev
+#	2. verify the property is set
+#
+
+log_assert "zpool set comment property on root vdev"
+
+log_must zpool set comment="openzfs" ${TESTPOOL} root
+
+COMMENT="$(zpool get -H -o value comment ${TESTPOOL} root)"
+if [ $? -ne 0 ]; then
+    log_fail "cant retrieve comment property from root vdev"
+fi
+
+if [ "$COMMENT" != "openzfs" ]; then
+    log_fail "unexpected value for comment property: $COMMENT != \"openzfs\""
+fi
+
+log_pass "zpool set comment property on root vdev"

tests/zfs-tests/tests/functional/vdev_zaps/vdev_zaps.kshlib

@@ -34,6 +34,10 @@ function get_top_vd_zap # dsk conf
 {
         get_conf_section "$1" "$2" | awk '/com.delphix:vdev_zap_top: [0-9]+/ {print $2}'
 }
+function get_root_vd_zap # conf
+{
+        awk '/com.klarasystems:vdev_zap_root: [0-9]+/ {print $2}' "$1"
+}
 
 function assert_has_sentinel # conf
 {
@@ -54,6 +58,15 @@ function assert_zap_common # pool vd lvl zapobj
         fi
 }
 
+function assert_root_zap # pool conf
+{
+        typeset pool=$1
+        typeset conf=$2
+
+        root_zap=$(get_root_vd_zap $conf)
+        assert_zap_common $pool "root vdev" "root" $root_zap
+}
+
 function assert_top_zap # pool vd conf
 {
         typeset pool=$1

tests/zfs-tests/tests/functional/vdev_zaps/vdev_zaps_001_pos.ksh

@@ -21,7 +21,7 @@
 #
 # Strategy:
 # 1. Create a pool with one disk.
-# 2. Verify that the disk has a top and leaf ZAP in its config and the MOS.
+# 2. Verify that the disk has a root, top and leaf ZAP in its config and the MOS.
 #
 
 . $STF_SUITE/include/libtest.shlib
@@ -35,6 +35,7 @@ log_must zpool create -f $TESTPOOL $DISK
 conf="$TESTDIR/vz001"
 log_must eval "zdb -PC $TESTPOOL > $conf"
 
+assert_root_zap $TESTPOOL "$conf"
 assert_top_zap $TESTPOOL $DISK "$conf"
 assert_leaf_zap $TESTPOOL $DISK "$conf"
 assert_has_sentinel "$conf"

tests/zfs-tests/tests/functional/vdev_zaps/vdev_zaps_002_pos.ksh

@@ -36,6 +36,7 @@ conf="$TESTDIR/vz002"
 log_must eval "zdb -PC $TESTPOOL > $conf"
 
 assert_has_sentinel "$conf"
+assert_root_zap $TESTPOOL "$conf"
 for DISK in $DISKS; do
 	assert_top_zap $TESTPOOL $DISK "$conf"
 	assert_leaf_zap $TESTPOOL $DISK "$conf"

tests/zfs-tests/tests/functional/vdev_zaps/vdev_zaps_003_pos.ksh

@@ -37,6 +37,7 @@ conf="$TESTDIR/vz003"
 log_must eval "zdb -PC $TESTPOOL > $conf"
 
 assert_has_sentinel "$conf"
+assert_root_zap $TESTPOOL "$conf"
 assert_top_zap $TESTPOOL "type: 'mirror'" "$conf"
 for DISK in $DISKS; do
 	assert_leaf_zap $TESTPOOL $DISK "$conf"

tests/zfs-tests/tests/functional/vdev_zaps/vdev_zaps_004_pos.ksh

@@ -40,6 +40,7 @@ log_must zpool create -f $TESTPOOL $DISK
 conf="$TESTDIR/vz004"
 log_must eval "zdb -PC $TESTPOOL > $conf"
 assert_has_sentinel "$conf"
+assert_root_zap $TESTPOOL "$conf"
 orig_top=$(get_top_vd_zap $DISK $conf)
 orig_leaf=$(get_leaf_vd_zap $DISK $conf)
 assert_zap_common $TESTPOOL $DISK "top" $orig_top

tests/zfs-tests/tests/functional/vdev_zaps/vdev_zaps_005_pos.ksh

@@ -37,6 +37,7 @@ log_must zpool create -f $TESTPOOL $DISK
 conf="$TESTDIR/vz005"
 log_must eval "zdb -PC $TESTPOOL > $conf"
 assert_has_sentinel "$conf"
+assert_root_zap $TESTPOOL "$conf"
 orig_top=$(get_top_vd_zap $DISK $conf)
 orig_leaf=$(get_leaf_vd_zap $DISK $conf)
 assert_zap_common $TESTPOOL $DISK "top" $orig_top

tests/zfs-tests/tests/functional/vdev_zaps/vdev_zaps_006_pos.ksh

@@ -39,6 +39,7 @@ conf="$TESTDIR/vz006"
 log_must eval "zdb -PC $TESTPOOL > $conf"
 
 assert_has_sentinel "$conf"
+assert_root_zap $TESTPOOL "$conf"
 orig_top=$(get_top_vd_zap ${DISK_ARR[1]} $conf)
 assert_zap_common $TESTPOOL ${DISK_ARR[1]} "top" $orig_top
 assert_leaf_zap $TESTPOOL ${DISK_ARR[1]} "$conf"

tests/zfs-tests/tests/functional/vdev_zaps/vdev_zaps_007_pos.ksh

@@ -39,6 +39,7 @@ conf="$TESTDIR/vz007"
 log_must eval "zdb -PC $TESTPOOL > $conf"
 
 assert_has_sentinel "$conf"
+assert_root_zap $TESTPOOL "$conf"
 orig_top=$(get_top_vd_zap "type: 'mirror'" $conf)
 orig_leaf0=$(get_leaf_vd_zap ${DISK_ARR[0]} $conf)
 orig_leaf1=$(get_leaf_vd_zap ${DISK_ARR[1]} $conf)