Added read-only (overlay) filesystem

stage2/07-enable-overlayfs/00-run.sh

@@ -0,0 +1,12 @@
+#!/bin/bash -e
+
+install -d "${ROOTFS_DIR}/etc/systemd/system/enable-overlayfs.target.wants"
+install -m 644 files/enable-overlayfs.service "${ROOTFS_DIR}/etc/systemd/system/"
+install -m 644 files/enable-overlayfs.target "${ROOTFS_DIR}/etc/systemd/system/"
+install -m 755 files/enable_overlayfs.sh "${ROOTFS_DIR}/usr/bin/"
+
+on_chroot << EOF
+ln -s /etc/systemd/system/enable-overlayfs.service /etc/systemd/system/enable-overlayfs.target.wants/enable-overlayfs.service
+systemctl daemon-reload
+systemctl set-default enable-overlayfs.target
+EOF

stage2/07-enable-overlayfs/files/enable-overlayfs.service

@@ -0,0 +1,10 @@
+[Unit]
+Description=Enable Overlay Filesystem
+After=multi-user.target
+
+[Service]
+Type=simple
+ExecStart=/usr/bin/enable_overlayfs.sh
+
+[Install]
+WantedBy=enable-overlayfs.target

stage2/07-enable-overlayfs/files/enable-overlayfs.target

@@ -0,0 +1,5 @@
+[Unit]
+Description=Enable Overlay Filesystem Target
+Requires=multi-user.target
+After=multi-user.target
+AllowIsolate=yes

stage2/07-enable-overlayfs/files/enable_overlayfs.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+/usr/bin/raspi-config nonint do_overlayfs 0
+systemctl set-default multi-user.target
+reboot