From ded31276c90e8103ad5f20d378af8a1dda33f43a Mon Sep 17 00:00:00 2001
From: Denis Benato <benato.denis96@gmail.com>
Date: Thu, 21 Mar 2024 21:58:09 +0100
Subject: [PATCH 1/3] Add support for /etc as a submodule

---
 __frzr-deploy | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/__frzr-deploy b/__frzr-deploy
index edf1c33..bc65f6b 100644
--- a/__frzr-deploy
+++ b/__frzr-deploy
@@ -325,6 +325,32 @@ main() {
 		tar xfO ${IMG_FILE} | btrfs receive --quiet ${DEPLOY_PATH}
 	fi
 
+	if [ -d "${SUBVOL}/etc" ]; then
+		echo "System image ${NAME} will use the /etc overlay"
+	else
+		echo "System image ${NAME} will use an /etc subvolume"
+
+		btrfs subvolume create "${SUBVOL}/etc"
+
+		btrfs subvolume create "${SUBVOL}/snapshots"
+
+		btrfs subvolume create "${SUBVOL}/snapshots/etc"
+
+		# copy every stock /etc (that has been moved to /usr/etc) file to the actual /etc
+		cp -a ${SUBVOL}/usr/etc/** ${SUBVOL}/etc/
+
+		# copy the machine-id file: this was created by systemd the very first boot and identify the machine:
+		# changing this will also make ssh warn about machine not matching.
+		if [ -f "/etc/machine-id" ]; then
+			cp -a /etc/machine-id ${SUBVOL}/etc/
+		else
+			echo "WARNING: no /etc/machine-id -- new machine-id will be regenerated at next boot"
+		fi
+
+		# Make a snapshot of /etc so that this state can be restored
+		btrfs subvolume snapshot ${SUBVOL}/etc ${SUBVOL}/snapshots/etc/0
+	fi
+
 	mkdir -p ${MOUNT_PATH}/boot/${NAME}
 	cp ${SUBVOL}/boot/vmlinuz-linux ${MOUNT_PATH}/boot/${NAME}
 	cp ${SUBVOL}/boot/initramfs-linux.img ${MOUNT_PATH}/boot/${NAME}

From 0cc9ad718d2f0bbbec51969ed4a8d8315d650d3b Mon Sep 17 00:00:00 2001
From: Denis Benato <benato.denis96@gmail.com>
Date: Fri, 22 Mar 2024 20:37:33 +0100
Subject: [PATCH 2/3] cp * instead of ** since cp -a is already recursive

---
 __frzr-deploy | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/__frzr-deploy b/__frzr-deploy
index bc65f6b..b93e364 100644
--- a/__frzr-deploy
+++ b/__frzr-deploy
@@ -337,7 +337,7 @@ main() {
 		btrfs subvolume create "${SUBVOL}/snapshots/etc"
 
 		# copy every stock /etc (that has been moved to /usr/etc) file to the actual /etc
-		cp -a ${SUBVOL}/usr/etc/** ${SUBVOL}/etc/
+		cp -a ${SUBVOL}/usr/etc/* ${SUBVOL}/etc/
 
 		# copy the machine-id file: this was created by systemd the very first boot and identify the machine:
 		# changing this will also make ssh warn about machine not matching.

From bd3be915e00397922e6349f7bbcc0daf00646d24 Mon Sep 17 00:00:00 2001
From: Denis Benato <benato.denis96@gmail.com>
Date: Fri, 22 Mar 2024 23:57:08 +0100
Subject: [PATCH 3/3] creating a subvolume needs the parent to be r/w

---
 __frzr-deploy | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/__frzr-deploy b/__frzr-deploy
index b93e364..4189068 100644
--- a/__frzr-deploy
+++ b/__frzr-deploy
@@ -330,10 +330,18 @@ main() {
 	else
 		echo "System image ${NAME} will use an /etc subvolume"
 
+		# unlock the subvolume to be able to create a nested subvolume
+		btrfs property set -f -ts "${SUBVOL}/" ro false
+
+		# create the nested subvolume for /etc
 		btrfs subvolume create "${SUBVOL}/etc"
 
+		# create the nested subvolume for /snapshots
 		btrfs subvolume create "${SUBVOL}/snapshots"
 
+		# re-lock the subvolume. ${SUBVOL}/etc will remain R/W
+		btrfs property set -f -ts "${SUBVOL}/" ro true
+
 		btrfs subvolume create "${SUBVOL}/snapshots/etc"
 
 		# copy every stock /etc (that has been moved to /usr/etc) file to the actual /etc