Add zettacache support to zfs-object-agent.service (openzfs#428)

cmd/zfs_object_agent/scripts/Makefile.am

@@ -1 +1,3 @@
-dist_bin_SCRIPTS = zoa_chaos_monkey
+dist_bin_SCRIPTS = \
+        zoa_chaos_monkey \
+        start_zoa

cmd/zfs_object_agent/scripts/start_zoa

@@ -0,0 +1,46 @@
+#!/bin/sh
+
+#
+# This script starts the ZFS Object Agent process.
+# It uses the following environment variables, typically set by zfs-object-agent.service
+# to determine which command line parameters to pass to the ZFS Object Agent process.
+#  - ZOA_LOG: File to log output to
+#  - ZOA_CONFIG: Configuration file to set tunables (toml/json/yaml"
+#  - ZETTACACHE_DEVICE: File/device to use for ZettaCache
+#  - ZOA_LOG_LEVEL : Sets the level of logging verbosity.
+#		     Values can be TRACE, DEBUG, INFO, WARN.
+#
+
+error() {
+	echo "$@" 1>&2
+}
+
+ZOA_LOG="${ZOA_LOG:-/var/log/zoa.log}"
+PARAMS="-o ${ZOA_LOG}"
+echo "Logging to: ${ZOA_LOG}"
+
+if [ ! -z $ZOA_CONFIG ]; then
+	echo "Config file: ${ZOA_CONFIG}"
+	PARAMS="${PARAMS} -t ${ZOA_CONFIG}"
+fi
+
+if [ ! -z $ZETTACACHE_DEVICE ]; then
+	echo "ZettaCache: ${ZETTACACHE_DEVICE}"
+	PARAMS="$PARAMS -c ${ZETTACACHE_DEVICE}"
+fi
+
+if [ ! -z $ZOA_LOG_LEVEL ]; then
+	if [ $ZOA_LOG_LEVEL = 'WARN' ]; then
+		: # WARN is the default log level.
+	elif [ $ZOA_LOG_LEVEL = 'INFO' ]; then
+		PARAMS="${PARAMS} -v"
+	elif [ $ZOA_LOG_LEVEL = 'DEBUG' ]; then
+		PARAMS="${PARAMS} -vv"
+	elif [ $ZOA_LOG_LEVEL = 'TRACE' ]; then
+		PARAMS="${PARAMS} -vvv"
+	else
+		error "Invalid log level setting: $ZOA_LOG_LEVEL; ignoring."
+	fi
+fi
+
+/sbin/zfs_object_agent ${PARAMS}

debian/zfsutils-linux.install

@@ -17,6 +17,8 @@ lib/udev/
 debian/tmp/etc/default/zfs etc/default/
 debian/tmp/etc/zfs/zfs-functions etc/zfs/
 etc/zfs/zpool.d/
+debian/tmp/etc/zfs/zoa_config.toml etc/zfs/
+debian/tmp/etc/zfs/zoa.conf etc/zfs/
 usr/lib/*/zfs/zpool.d/
 usr/lib/*/zfs/zpool_influxdb
 sbin/fsck.zfs
@@ -38,6 +40,7 @@ sbin/zoa_test
 cmd/zfs_object_agent/libzoa.so lib/
 usr/bin/zvol_wait
 usr/bin/zoa_chaos_monkey
+usr/bin/start_zoa
 usr/sbin/arc_summary
 usr/sbin/arcstat
 usr/sbin/dbufstat

etc/systemd/system/zfs-object-agent.service.in

@@ -8,7 +8,8 @@ Before=zfs-import-cache.service
 Environment="RUST_BACKTRACE=1"
 Environment="AWS_SECRET_ACCESS_KEY="
 Environment="AWS_ACCESS_KEY_ID="
-ExecStart=/sbin/zfs_object_agent -vv
+EnvironmentFile=-/etc/zfs/zoa.conf
+ExecStart=/usr/bin/start_zoa
 Restart=always
 
 [Install]

etc/zfs/Makefile.am

@@ -8,7 +8,9 @@ dist_pkgsysconf_DATA = \
 	vdev_id.conf.sas_direct.example \
 	vdev_id.conf.sas_switch.example \
 	vdev_id.conf.multipath.example \
-	vdev_id.conf.scsi.example
+	vdev_id.conf.scsi.example \
+	zoa.conf \
+	zoa_config.toml
 
 pkgsysconf_SCRIPTS = \
 	zfs-functions

etc/zfs/zoa.conf

@@ -0,0 +1,4 @@
+ZOA_LOG=/var/log/zoa.log
+ZOA_LOG_LEVEL=DEBUG
+ZOA_CONFIG=/etc/zfs/zoa_config.toml
+ZETTACACHE_DEVICE=

etc/zfs/zoa_config.toml

@@ -0,0 +1,4 @@
+#
+# This config file overrides default values for tunable parameters in
+# the ZFS Object Agent.
+#

rpm/generic/zfs.spec.in

@@ -478,6 +478,7 @@ systemctl --system daemon-reload >/dev/null || true
 %{_bindir}/zvol_wait
 # Optional zfs_object_agent script
 %{_bindir}/zoa_chaos_monkey
+%{_bindir}/start_zoa
 # Optional Python 2/3 scripts
 %{_bindir}/arc_summary
 %{_bindir}/arcstat
@@ -512,6 +513,8 @@ systemctl --system daemon-reload >/dev/null || true
 %endif
 %config(noreplace) %{_sysconfdir}/%{name}/zed.d/*
 %config(noreplace) %{_sysconfdir}/%{name}/zpool.d/*
+%config(noreplace) %{_sysconfdir}/%{name}/zoa_config.toml
+%config(noreplace) %{_sysconfdir}/%{name}/zoa.conf
 %config(noreplace) %{_sysconfdir}/%{name}/vdev_id.conf.*.example
 %attr(440, root, root) %config(noreplace) %{_sysconfdir}/sudoers.d/*
 %if %{with pam}