#/bin/sh
#
#	$NetBSD: zfsroot.rc,v 1.2 2020/02/23 05:15:54 roy Exp $

echo "Starting root on ZFS boot strapper"

# Abort on any error
set -e

# Configurable - define the ZFS root pool and ROOT.
# XXX Can these be set in boot.cfg?
# Assumption - the root pool is set to legacy mount.
rpool=rpool
rroot=ROOT

# Assumption - the boot device is named boot.
# Could use /dev/dk0, /dev/wd0a, etc instead.
# XXX Can be exposed by sysctl kern.boot_device?
bootdev="NAME=boot"

# Setup some stuff incase things go south and we drop to the shell
export HOME=/
export PATH=/sbin:/bin:/usr/sbin:/usr/bin
umask 022

# Avoid having the solaris and zfs modules in ramdisk directly.
# Means we don't need to update the ramdisk with the kernel modules
# or load them from boot.cfg so it's less pain for the user.
#bootdev="$(/sbin/sysctl -n kern.boot_device)"
modpath="$(/sbin/sysctl -n kern.module.path)"
echo "Loading needed kernel modules from $bootdev:$modpath"
/sbin/mount -o ro "$bootdev" /mnt
for m in solaris zfs; do
	/sbin/modload "/mnt/$modpath/$m/$m.kmod"
done
/sbin/umount /mnt

# FIXME XXX Sometimes zpool import gets SIGBUS
# Ensure that we are in a writable directory to try and capture a coredump
# Not that we actually get a coredump ....
cd /tmp

echo "Importing $rpool"
/sbin/zpool import -f -N "$rpool"

echo "Mounting $rpool/$rroot to /altroot"
/sbin/mount -t zfs "$rpool/$rroot" /altroot;

# This ensures that rc.d/mountall mounts all ZFS mounts set to automount.
if [ ! -e /altroot/etc/zfs/zpool.cache ]; then
	echo >/altroot/etc/zfs/zpool.cache
fi

echo "Pivoting to /altroot, welcome to root on ZFS"
/sbin/sysctl -w init.root=/altroot