support systemd shutdown pivot root back to initramfs

2 files changed, 36 insertions, 3 deletions

diff --git a/builder/dnbd3-rootfs/hooks/copy-dracut-systemd-files-into-newroot.sh b/builder/dnbd3-rootfs/hooks/copy-dracut-systemd-files-into-newroot.sh
new file mode 100644
index 00000000..1e9366e2
--- /dev/null
+++ b/builder/dnbd3-rootfs/hooks/copy-dracut-systemd-files-into-newroot.sh
@@ -0,0 +1,24 @@
+#!/bin/env bash
+# Dracut may not be installed on the new root. Thus copy all services over.
+systemdsystemunitdir="$(
+    dirname "$(find / -name dracut-mount.service -type f -print -quit)")"
+mkdir --parents "${NEWROOT}/${systemdsystemunitdir}"
+for file in \
+    dracut-cmdline.service \
+    dracut-initqueue.service \
+    dracut-mount.service \
+    dracut-pre-mount.service \
+    dracut-pre-pivot.service \
+    dracut-pre-trigger.service \
+    dracut-pre-udev.service; do
+        cp "${systemdsystemunitdir}/$file" \
+            "${NEWROOT}/${systemdsystemunitdir}/$file"
+        ln -s ../"$file" \
+            "${NEWROOT}/${systemdsystemunitdir}/initrd.target.wants/$file"
+done
+
+# Needed to be able to go back to dracut at system shutdown.
+mkdir /temp_mnt
+mount --bind / /temp_mnt/
+cp -rT /temp_mnt /run/initramfs
+umount /temp_mnt && rmdir /temp_mnt
diff --git a/builder/dnbd3-rootfs/module-setup.sh b/builder/dnbd3-rootfs/module-setup.sh
index 9b931c44..a1514f91 100755
--- a/builder/dnbd3-rootfs/module-setup.sh
+++ b/builder/dnbd3-rootfs/module-setup.sh
@@ -6,6 +6,12 @@ core.import logging
 core.import utils
 
 # TODO set log level via dracut logging options
+# (use $dracut_args
+#((len=${#dracut_args[@]}))
+#for ((i=0; i < len; i++)); do
+    #[[ ${dracut_args[$i]} == "--regenerate-all" ]] && \
+        #unset dracut_args[$i]
+#done
 logging.set_log_level debug
 logging.set_commands_log_level debug
 
@@ -78,7 +84,7 @@ check() {
 
 depends() {
     # DEBUG: echo base network bash kernel-modules systemd-initrd dracut-systemd fs-lib rootfs-block
-    echo base network bash kernel-modules
+    echo base network bash kernel-modules shutdown
     # NOTE: btrfs module should be used if it would work.
 }
 
@@ -145,11 +151,14 @@ install() {
             /usr/bin/dnbd3root
         inst_simple "${moddir}/services/dnbd3root.service" \
             "${systemdsystemunitdir}/dnbd3root.service"
-        # don't kill at switch_root
+
+        # copy systemd services to new root (so they don't get killed after
+        # switch_root)
         mkdir -p "${initdir}/${systemdsystemunitdir}/initrd-root-fs.target.wants"
         ln_r "${systemdsystemunitdir}/dnbd3root.service" \
             "${systemdsystemunitdir}/initrd-root-fs.target.wants/dnbd3root.service"
-        inst_hook pre-pivot 95 "$moddir/hooks/copy-dnbd3-generator-into-newroot.sh"
+        inst_hook pre-pivot 00 "$moddir/hooks/copy-dnbd3-generator-into-newroot.sh"
+        inst_hook pre-pivot 00 "$moddir/hooks/copy-dracut-systemd-files-into-newroot.sh"
     else
         inst_hook pre-mount 10 "$moddir/hooks/prepare-root-partition.sh"
     fi