#!/bin/sh

# $FreeBSD$
#
# PROVIDE: memzil
# REQUIRE: FILESYSTEMS
# KEYWORD: nojail
#
# Add/Remove a memory based LOG device to a zfs pool at system boot/shutdown time.
#
# memzil_enable=YES|NO			Enable memzil pools
# memzil_pools="list of pools|AUTO"	Pools to add a memory based log to
# memzil_bootfs=YES|NO			Only add a log to a bootfs pool if set to YES
# memzil_size="512M"			Size of md(4) device -s option
#
# WARNING: This rc script will dynamically add an md(4) LOG device to a
# WARNING: ZFS pool at boot time and remove it correctly at system shudown
# WARNING: time. However, if the system panics, resets, or is otherwise
# WARNING: hard powered off, the associated pool with the memory based
# WARNING: LOG device will not be usable until it is recovered.
#
# WARNING: For instance, for a beadm(1) configured system:
# WARNING: zpool import -f -m sys
# WARNING: zpool remove md0 sys
# WARNING: zfs set mountpoint=/mnt sys/ROOT/default sys
# WARNING: zpool set cachefile=/mnt/boot/zfs/zpool.cache sys
# WARNING: zfs set mountpoint=legacy sys/ROOT/default sys
# WARNING: zfs unmount -a
# WARNING: reboot
#
# WARNING: Data loss is possible!! Use at your own risk!!
# WARNING: Data loss is possible!! Use at your own risk!!
# WARNING: Data loss is possible!! Use at your own risk!!

. /etc/rc.subr

name="memzil"
rcvar="${name}_enable"

start_cmd="${name}_start"
stop_cmd="${name}_stop"
show_cmd="${name}_show"
extra_commands="show"

memzil_show()
{
	if [ -z "${memzil_pools}" ]; then
		err 1 "You must define memzil_pools with at least one pool name or AUTO"
	fi

	case "${memzil_pools:-NONE}" in
	[Aa][Uu][Tt][Oo])	pools=`zpoollist`
				;;
	* )			pools="${memzil_pools:-NONE}"
	esac

	for pool in $pools; do

		# Validate any non-AUTO memzil_pools
                #
                zpool list $pool > /dev/null 2>&1
		if [ $? -ne 0 ]; then
			warn "Pool $pool does not exist"
			continue
		fi

		logdevs $pool | while read line; do
			echo $line
		done
	done
}



memzil_start()
{

	if [ -z "${memzil_pools}" ]; then
		err 1 "You must define memzil_pools with at least one pool name or AUTO"
	fi

	case "${memzil_pools}" in
	[Aa][Uu][Tt][Oo])	pools=`zpoollist`
				;;
	* )			pools="${memzil_pools}"
	esac

	echo "Adding an md(4) based log to pools: $pools"
	for pool in $pools; do

		# Validate any non-AUTO memzil_pools
                #
                zpool list $pool > /dev/null 2>&1
		if [ $? -ne 0 ]; then
			warn "Pool $pool does not exist"
			continue
		fi

		# log device already present?
		#
		logs=`logdevs $pool | wc -l`
		if [ $logs -gt 0 ]; then
			echo "Pool $pool already contains ${logs##*[[:blank:]]} log device(s)"
			continue
		else
			echo "No log devices present on pool $pool"
		fi

		# Is this a bootfs?
		#
		bootfs=`zpool get bootfs $pool | grep bootfs | awk '{ print $3; }'`
		if [ "$bootfs" != "-" ]; then
			if [ "${memzil_bootfs:-NO}" = "YES" ]; then
				echo "Adding memzil to bootfs pool $pool"
				echo "zpool set bootfs=\"\" ${pool:-badpool}"
				zpool set bootfs="" ${pool:-badpool}
			else
				echo "Not adding memzil to bootfs pool $pool"
				continue
			fi
		fi

		# Add the device
		#
		logdev=`mdconfig -a -t malloc -s ${memzil_size:-512M} -o reserve`
		echo "Adding $logdev to pool $pool"
		zpool add ${pool:-badpool} log ${logdev:-nologdev}

		# Restore possible bootfs value
		#
		if [ "$bootfs" != "-" ]; then
			zpool set "bootfs=$bootfs" $pool
			zpool get bootfs $pool
		fi

	done

}

memzil_stop()
{

	case "${memzil_pools:-NONE}" in
	[Aa][Uu][Tt][Oo])	pools=`zpoollist`
				;;
	* )			pools="${memzil_pools:-NONE}"
	esac

	echo "Removing any md log devices from pool(s): $pools"

	for pool in $pools; do

		# Validate any non-AUTO memzil_pools
                #
                zpool list $pool > /dev/null 2>&1
		if [ $? -ne 0 ]; then
			warn "Pool $pool does not exist"
			continue
		fi

		# Even though memzil only adds non-mirrored md devices, remove
		# both mirrored and non-mirrored units.
		#
		logdevs $pool | while read poolname ismirror device junk; do
			if [ "${device%%[[:digit:]]*}" = "md" ]; then
				echo "zpool remove ${pool:-badpool} $device"
				zpool remove ${pool:-badpool} $device
				if [ "$?" != "0" ]; then
					echo "zpool detach ${pool:-badpool} $device"
					zpool detach ${pool:-badpool} $device
				fi
				echo "mdconfig -d -u $device"
				mdconfig -d -u $device
			fi
		done

	done

}


zpoollist()
{
	while read t1 tx; do
		echo $t1
	done << __EOT__
$(zpool list -H)
__EOT__
}

logdevs()
{
	pool="${1:-nopool}"
	output=0
	ismirror="nomirror"
	zpool status $pool | while read _line; do
        	if [ "`echo $_line | cut -f1 -d':'`" = "errors" -o "$_line" = "cache" ]; then
                	output=0
        	fi
        	if [ "$output" = "1" -a "$_line" != "" ]; then
                	if [ "`echo $_line | cut -f1 -d'-'`" = "mirror" ]; then
                        	ismirror=`echo $_line | awk '{ print $1; }'`
                	else
                        	echo $pool $ismirror $_line
                	fi
        	else
                	if [ "$_line" = "logs" ]; then
                        	output=1
                	fi
        	fi
	done
}


load_rc_config $name
run_rc_command "$1"