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#!/bin/zsh
# root-fs stop — final sync before halt/poweroff/reboot
#
# Originally this script set the ZFS root dataset readonly=on as a
# defensive "clean state for next boot" measure. That was actively
# wrong: it made / read-only BEFORE zyginit's outer shutdown sequence
# finished (destroy_socket's unlink of /var/run/zyginit.sock, the
# explicit zpool sync + umountall, etc.). Every subsequent write
# failed silently, so the next boot saw stale state — most visibly
# the un-removed /var/run/zyginit.sock that wedged zygctl post-reboot.
#
# ZFS is transactionally consistent — it doesn't need a "freeze"
# before shutdown. zyginit's main shutdown sequence (`zpool sync`,
# umountall -l, sync) plus the kernel's own vfs_syncall inside
# uadmin's mdboot path is enough to guarantee txg commit before the
# hardware reset.
#
# UFS root would still need remount,ro for clean fsck. Hammerhead's
# BE is ZFS, so this script is effectively a no-op (just a final
# `zpool sync` as defense in depth). Add UFS handling here if/when
# UFS root is supported.

set -u

# Defense-in-depth: final zpool sync. zyginit's outer shutdown also
# calls `zpool sync` post-shutdown_services; this covers the brief
# window between filesystem/stop.sh's `umountall -l` and that call.
/usr/sbin/zpool sync 2>/dev/null || true

exit 0