# ZFS boot stub for initramfs-tools.

zfs_test_import()
{
	if zpool import -o readonly=on -N "$ZFS_RPOOL" >/dev/null 2>&1
	then
		ZFS_HEALTH=$(zpool list -H -o health "$ZFS_RPOOL" 2>/dev/null)
	fi
	while [ "$retry_nr" -lt "$delay" ]
	do
		ZFS_STDERR=$(zpool export "$ZFS_RPOOL" >/dev/null)
		if ! echo "$ZFS_STDERR" | grep -q "is busy"
		then
			break
		fi
		/bin/sleep 1
		retry_nr=$(( $retry_nr + 1 ))
	done
}

mountroot()
{
	[ "$quiet" != "y" ] && log_begin_msg "Running /scripts/local-top"
	run_scripts /scripts/local-top
	[ "$quiet" != "y" ] && log_end_msg

	[ "$quiet" != "y" ] && log_begin_msg "Running /scripts/local-premount"
	run_scripts /scripts/local-premount
	[ "$quiet" != "y" ] && log_end_msg

	# Wait for all of the /dev/{hd,sd}[a-z] device nodes to appear.
	wait_for_udev

	modprobe zfs zfs_autoimport_disable=1

	ZFS_BOOTFS=${ROOT#ZFS=}
	ZFS_RPOOL=$(echo "$ZFS_BOOTFS" | sed -e 's,/.*,,')

	delay=${ROOTDELAY:-0}

	if [ "$delay" -gt 0 ]
	then
		# Try to import the pool read-only.  If it does not import with
		# the ONLINE status, wait and try again.  The pool could be
		# DEGRADED because a drive is really missing, or it might just
		# be slow to be detected.
		retry_nr=0
		zfs_test_import
		while [ "$retry_nr" -lt "$delay" ] && [ "$ZFS_HEALTH" != "ONLINE" ]
		do
			[ "$quiet" != "y" ] && log_begin_msg "Retrying ZFS read-only import"
			/bin/sleep 1
			zfs_test_import
			retry_nr=$(( $retry_nr + 1 ))
			[ "$quiet" != "y" ] && log_end_msg
		done
		unset retry_nr
		unset ZFS_HEALTH
	fi
	unset delay

	# At this point, the pool either imported cleanly, or we ran out of the
	# allowed time (rootdelay).  Perform the read-write import.
	ZFS_STDERR=$(zpool import -N "$ZFS_RPOOL" 2>&1)
	ZFS_ERROR=$?

	if [ "$ZFS_ERROR" -ne 0 ]
	then
		panic "Command: zpool import -N $ZFS_RPOOL
Message: $ZFS_STDERR
Error: $ZFS_ERROR

Manually import the root pool at the command prompt and then exit.
Hint: Try:  zpool import -f -R / -N $ZFS_RPOOL"
	fi

	# Set elevator=noop on the root pool's vdevs' disks.  ZFS already
	# does this for wholedisk vdevs (for all pools), so this is only
	# important for partitions.
	zpool status -L "$ZFS_RPOOL" 2>/dev/null |
		awk '/^\t / && !/(mirror|raidz)/ {
			dev=$1;
			sub(/[0-9]+$/, "", dev);
			print dev
		}' |
		while read i
	do
		if [ -e "/sys/block/$i/queue/scheduler" ]
		then
			echo noop > "/sys/block/$i/queue/scheduler"
		fi
	done

	# Force the mountpoint to the only correct value for a root filesystem.
	[ "$quiet" != "y" ] && log_begin_msg "Setting mountpoint=/ on ZFS filesystem $ZFS_BOOTFS"
	ZFS_STDERR=$(zfs set mountpoint=/ "$ZFS_BOOTFS" 2>&1)
	[ "$quiet" != "y" ] && log_end_msg

	# Ideally, the root filesystem would be mounted like this:
	#
	#   zpool import -R "$rootmnt" -N "$ZFS_RPOOL"
	#   zfs mount -o mountpoint=/ "$ZFS_BOOTFS"
	#
	# but the MOUNTPOINT prefix is preserved on descendent filesystem after
	# the pivot into the regular root, which later breaks things like
	# `zfs mount -a` and the /etc/mtab refresh.

	[ "$quiet" != "y" ] && log_begin_msg "Mounting ZFS filesystem $ZFS_BOOTFS"
	ZFS_STDERR=$(mount -t zfs -o zfsutil "$ZFS_BOOTFS" "$rootmnt" 2>&1)
	ZFS_ERROR=$?
	[ "$quiet" != "y" ] && log_end_msg

	if [ "$ZFS_ERROR" -ne 0 ]
	then
		panic "Command: mount -t zfs -o zfsutil $ZFS_BOOTFS $rootmnt
Message: $ZFS_STDERR
Error: $ZFS_ERROR

Manually mount the root filesystem on $rootmnt and then exit."
	fi

	unset ZFS_BOOTFS
	unset ZFS_RPOOL
	unset ZFS_STDERR
	unset ZFS_ERROR

	[ "$quiet" != "y" ] && log_begin_msg "Running /scripts/local-bottom"
	run_scripts /scripts/local-bottom
	[ "$quiet" != "y" ] && log_end_msg
}