Enabling the shutdown hook and using systemd v31 (which is yet to be released), means that on shutdown the root will be pivoted to /run/initramfs, from where the rootfs and all its submonuts (such as /usr) are unmounted cleanly. The same functionality will be supported in a future release of initscript. A natural next step is to add an "/usr"-hook, which mounts the /usr partition (if it exists) in the initramfs, so initscripts (and systemd) can always rely on it being mounted, and we no longer need to move some binaries/libraries to /bin, /sbin and /lib (as this does not work well at the moment). One might argue that this functionality does not beling in mkinitrd. The reason I propose it for inclusion here is: - it is independent of initscripts, so does not really belong there either. - in the future one might imagine extending this to integrate more tightly with the rest of the initramfs (e.g. store state/logs in /run/initramfs to ease debugging, or add shutdown-hooks, to go with the boot-hooks, to gracefully tear down things such as dm or nfs mounts at shutdown). - by behaving like dracut, integrating with systemd became trivial, and IMHO there is no point in systemd/initscripts/dracut/mkinitrd differing at the interface level. Signed-off-by: Tom Gundersen <teg@jklm.no> --- Makefile | 1 + hooks/shutdown | 11 +++++++++++ install/shutdown | 19 +++++++++++++++++++ shutdown | 10 ++++++++++ 4 files changed, 41 insertions(+), 0 deletions(-) create mode 100644 hooks/shutdown create mode 100644 install/shutdown create mode 100644 shutdown diff --git a/Makefile b/Makefile index 18df47f..d4bb4e1 100644 --- a/Makefile +++ b/Makefile @@ -35,6 +35,7 @@ install: all chmod 755 ${DESTDIR}/bin/lsinitcpio ${DESTDIR}/sbin/mkinitcpio install -m644 mkinitcpio.conf ${DESTDIR}/etc/mkinitcpio.conf + install -m755 -t ${DESTDIR}/lib/initcpio/shutdown shutdown install -m755 -t ${DESTDIR}/lib/initcpio init install -m644 -t ${DESTDIR}/lib/initcpio init_functions functions install -m644 01-memdisk.rules ${DESTDIR}/lib/initcpio/udev/01-memdisk.rules diff --git a/hooks/shutdown b/hooks/shutdown new file mode 100644 index 0000000..ea52796 --- /dev/null +++ b/hooks/shutdown @@ -0,0 +1,11 @@ +# vim: set ft=sh: +run_hook () +{ + msg -n ":: Creating shutdown ramfs..." + mkdir -p /run/initramfs/bin + cp /bin/busybox /run/initramfs/bin + cp /shutdown /run/initramfs + cd /run/initramfs/bin + ./busybox --install -s . + cp /shutdown /run/initramfs/ +} diff --git a/install/shutdown b/install/shutdown new file mode 100644 index 0000000..9f8076b --- /dev/null +++ b/install/shutdown @@ -0,0 +1,19 @@ +# vim:set ft=sh: + +build() +{ + MODULES="" + BINARIES="" + FILES="" + SCRIPT="shutdown" + add_binary /lib/initcpio/shutdown /shutdown +} + +help () +{ +cat <<HELPEOF + This hook will create a shutdown initrd in /run/mkinitramfs + that we can pivot to on shutdown in order to unmount / + (and any submounts such as /usr) cleanly. +HELPEOF +} diff --git a/shutdown b/shutdown new file mode 100644 index 0000000..5fb6e46 --- /dev/null +++ b/shutdown @@ -0,0 +1,10 @@ +#!/bin/sh +# shutdown + +# unmount everything that was mounted on the old root +umount `mount | awk '{ print $3 }' | grep "^/oldroot" | sort -r | tr '\n' ' '` + +# reboot / poweroff / halt, depending on the argument passed by init +[ "$1" = "reboot" ] && reboot -f +[ "$1" = "poweroff" ] && poweroff -f +[ "$1" = "halt" ] && halt -f -- 1.7.6