[PATCH v6 1/1] expand-on-first-boot: Switch from resize2fs to systemd-growfs

[Henning Schild <henning.schild@siemens.com>]

From: Tobias Schmidl <tobiasschmidl@siemens.com>

We want to be more versatile in our approach of resizing the last
partition. Therefore we switch from resize2fs to systemd-growfs.

This allows for ext4, btrfs, xfs, and dm-crypt partitions to be resized.

Signed-off-by: Tobias Schmidl <tobiasschmidl@siemens.com>
Signed-off-by: Henning Schild <henning.schild@siemens.com>
---
 ...oot_1.1.bb => expand-on-first-boot_1.2.bb} |  3 +-
 .../files/expand-last-partition.sh            | 31 ++++++++++++++++---
 2 files changed, 28 insertions(+), 6 deletions(-)
 rename meta/recipes-support/expand-on-first-boot/{expand-on-first-boot_1.1.bb => expand-on-first-boot_1.2.bb} (88%)

diff --git a/meta/recipes-support/expand-on-first-boot/expand-on-first-boot_1.1.bb b/meta/recipes-support/expand-on-first-boot/expand-on-first-boot_1.2.bb
similarity index 88%
rename from meta/recipes-support/expand-on-first-boot/expand-on-first-boot_1.1.bb
rename to meta/recipes-support/expand-on-first-boot/expand-on-first-boot_1.2.bb
index 1703a648ca27..8d11aef00927 100644
--- a/meta/recipes-support/expand-on-first-boot/expand-on-first-boot_1.1.bb
+++ b/meta/recipes-support/expand-on-first-boot/expand-on-first-boot_1.2.bb
@@ -1,13 +1,14 @@
 # Resize last partition to full medium size on fist boot
 #
 # This software is a part of ISAR.
-# Copyright (c) Siemens AG, 2018
+# Copyright (c) Siemens AG, 2018-2022
 #
 # SPDX-License-Identifier: MIT
 
 inherit dpkg-raw
 
 DESCRIPTION = "This service grows the last partition to the full medium during first boot"
+MAINTAINER = "isar-users <isar-users@googlegroups.com>"
 
 DEBIAN_DEPENDS = "systemd, sed, grep, coreutils, mount, e2fsprogs, fdisk, util-linux"
 
diff --git a/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh b/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
index 759ff8b61ccd..046a1394d213 100755
--- a/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
+++ b/meta/recipes-support/expand-on-first-boot/files/expand-last-partition.sh
@@ -3,7 +3,7 @@
 # Resize last partition to full medium size
 #
 # This software is a part of ISAR.
-# Copyright (c) Siemens AG, 2018
+# Copyright (c) Siemens AG, 2018-2022
 #
 # SPDX-License-Identifier: MIT
 
@@ -57,8 +57,29 @@ sfdisk -d "${BOOT_DEV}" 2>/dev/null | \
 # Inform the kernel about the partitioning change
 partx -u "${LAST_PART}"
 
-# Do not fail resize2fs if no mtab entry is found, e.g.,
-# when using systemd mount units.
-export EXT2FS_NO_MTAB_OK=1
+# this is for debian stretch or systemd < 236
+if [ ! -x /lib/systemd/systemd-growfs ]; then
+	# Do not fail resize2fs if no mtab entry is found, e.g.,
+	# when using systemd mount units.
+	export EXT2FS_NO_MTAB_OK=1
 
-resize2fs "${LAST_PART}"
+	resize2fs "${LAST_PART}"
+	exit 0
+if
+
+if grep -q x-systemd.growfs /etc/fstab; then
+	echo "Found x-systemd.growfs option in /etc/fstab, won't call it explicitly." >&2
+	exit 0
+fi
+
+# mount $LAST_PART out of tree, so we won't conflict with other mounts
+MOUNT_POINT=$(mktemp -d -p /mnt "$(basename "$0").XXXXXXXXXX")
+if [ ! -d "${MOUNT_POINT}" ]; then
+	echo "Cannot create temporary mount point ${MOUNT_POINT}." >&2
+	exit 1
+fi
+
+mount "${LAST_PART}" "${MOUNT_POINT}"
+/lib/systemd/systemd-growfs "${MOUNT_POINT}"
+umount "${MOUNT_POINT}"
+rmdir "${MOUNT_POINT}"
-- 
2.37.4