ro: Inject overlayfs, using DATADEV '/data' partition as 'upper'; Disable rootfs resize @ init (1st boot)

/etc/fstab didn't work to mount the overlayfs (boot freeze due to some dependencies).

Hence we use our own 'overlay_mount.service' Before 'local_fs.target',
which mounts '/data' and its overlays.

We also disable rootfs resize @ init (1st boot),
since the rootfs is immutable from here on.

4 files changed, 49 insertions, 2 deletions

diff --git a/stage2/01-sys-tweaks/00-patches/series b/stage2/01-sys-tweaks/00-patches/series
index aee0402..19b04f5 100644
--- a/stage2/01-sys-tweaks/00-patches/series
+++ b/stage2/01-sys-tweaks/00-patches/series
@@ -2,4 +2,3 @@
 02-swap.diff
 04-inputrc.diff
 05-path.diff
-07-resize-init.diff
diff --git a/stage2/01-sys-tweaks/01-run.sh b/stage2/01-sys-tweaks/01-run.sh
index c1836f9..95a4d74 100755
--- a/stage2/01-sys-tweaks/01-run.sh
+++ b/stage2/01-sys-tweaks/01-run.sh
@@ -1,5 +1,8 @@
 #!/bin/bash -e
 
+install -m 644 files/overlay_mount.service	"${ROOTFS_DIR}/lib/systemd/system/"
+install -m 755 files/overlay_mount	        "${ROOTFS_DIR}/etc/init.d/"
+
 install -m 755 files/resize2fs_once	"${ROOTFS_DIR}/etc/init.d/"
 
 install -d				"${ROOTFS_DIR}/etc/systemd/system/rc-local.service.d"
@@ -40,12 +43,16 @@ if [ "${USE_QEMU}" = "1" ]; then
 	install -m 644 files/90-qemu.rules "${ROOTFS_DIR}/etc/udev/rules.d/"
 	on_chroot << EOF
 systemctl disable resize2fs_once
+systemctl enable overlay_mount
 EOF
 	echo "leaving QEMU mode"
 else
 	on_chroot << EOF
-systemctl enable resize2fs_once
+#systemctl enable resize2fs_once
+systemctl disable resize2fs_once
+systemctl enable overlay_mount
 EOF
+	echo "leaving normal mode"
 fi
 
 on_chroot <<EOF
diff --git a/stage2/01-sys-tweaks/files/overlay_mount b/stage2/01-sys-tweaks/files/overlay_mount
new file mode 100755
index 0000000..50a8965
--- /dev/null
+++ b/stage2/01-sys-tweaks/files/overlay_mount
@@ -0,0 +1,28 @@
+#!/bin/sh
+### BEGIN INIT INFO
+# Provides:          overlay_mount
+# Required-Start:
+# Required-Stop:
+# Default-Start: 3
+# Default-Stop:
+# Short-Description: Overlay the root filesystem with rw folder
+# Description:
+### END INIT INFO
+. /lib/lsb/init-functions
+case "$1" in
+  start)
+    log_daemon_msg "Starting overlay_mount"
+    /bin/mount -t ext4 DATADEV -odefaults,noatime /data &&
+    /bin/mount -t overlay overlay -odefaults,noatime,lowerdir=/etc,upperdir=/data/etc/upper,workdir=/data/etc/work /etc &&
+    /bin/mount -t overlay overlay -odefaults,noatime,lowerdir=/home,upperdir=/data/home/upper,workdir=/data/home/work /home &&
+    /bin/mount -t overlay overlay -odefaults,noatime,lowerdir=/srv,upperdir=/data/srv/upper,workdir=/data/srv/work /srv &&
+    /bin/mount -t overlay overlay -odefaults,noatime,lowerdir=/tmp,upperdir=/data/tmp/upper,workdir=/data/tmp/work /tmp &&
+    /bin/mount -t overlay overlay -odefaults,noatime,lowerdir=/var,upperdir=/data/var/upper,workdir=/data/var/work /var &&
+    log_end_msg $?
+    ;;
+  *)
+    echo "Usage: $0 start" >&2
+    exit 3
+    ;;
+esac
+
diff --git a/stage2/01-sys-tweaks/files/overlay_mount.service b/stage2/01-sys-tweaks/files/overlay_mount.service
new file mode 100644
index 0000000..f3687c9
--- /dev/null
+++ b/stage2/01-sys-tweaks/files/overlay_mount.service
@@ -0,0 +1,13 @@
+[Unit]
+Description=OverlayFS mount service
+DefaultDependencies=no
+Before=local-fs.target
+
+[Service]
+Type=oneshot
+ExecStart=/etc/init.d/overlay_mount start
+
+[Install]
+WantedBy=local-fs.target
+Alias=overlay_mount.service
+