Rewrite datactl command (#1046)

* Rewrite datactl command

Prepare the target partition as part of the datactl command. Rely on
partlabel for the target disk since we are always using GPT on the
target disk. Use systemd and partlabel mechanism to wait and find
the target data disk. Keep using the file system label to identify
the source disk.

Also use e2image instead of raw dd to move data. This should
speed up the processes significantly.

* Fix corner case when reusing same disk again

buildroot-external/rootfs-overlay/usr/libexec/hassos-data

@@ -1,83 +1,24 @@
 #!/bin/sh
-# shellcheck disable=SC2039
 # ==============================================================================
-# HassOS data partition handler
+# Home Assistant OS data partition migration script
 # ==============================================================================
 set -e
 
-OPTION_FILE=/mnt/overlay/data.opt
+# Rely on systemd-udev symlinks to find current data partition by fs label
+OLD_DEVICE_CHILD="$(readlink -f "/dev/disk/by-label/hassos-data")"
 
-# New data partition exits
-if ! [ -e "${OPTION_FILE}" ]; then
-    echo "[INFO] No data option found"
-    exit 0
-else
-    NEW_DEVICE_ROOT="$(cat ${OPTION_FILE})"
-    rm ${OPTION_FILE}
-fi
+# Rely on systemd-udev symlinks to find external data partition by partlabel
+NEW_DEVICE_CHILD="$(readlink -f "/dev/disk/by-partlabel/hassos-data-external")"
 
-# Get device information
-OLD_DEVICE_CHILD="$(findfs LABEL="hassos-data")"
-OLD_DEVICE_ROOT="/dev/$(lsblk -no pkname "${OLD_DEVICE_CHILD}")"
-OLD_PART_NUM="${OLD_DEVICE_CHILD: -1}"
-
-# Wait for devices
-timeout 90 \
-    ash -c \
-        "until [ -e \"${NEW_DEVICE_ROOT}\" ]; do sleep 5; done" \
-            > /dev/null 2>&1 || true;
-
-# Check if block device is exists
-if [ ! -b "${NEW_DEVICE_ROOT}" ]; then
-    echo "[ERROR] No block device ${NEW_DEVICE_ROOT}!"
-    exit 1
-fi
-echo "[INFO] Cleanup device ${NEW_DEVICE_ROOT}!"
-sgdisk -Z "${NEW_DEVICE_ROOT}"
-
-# Create new partition
-echo "[INFO] Create new hassos-data partition"
-sgdisk -o "${NEW_DEVICE_ROOT}"
-sgdisk \
-    -n "0:0:0" \
-    -c "0:hassos-data" \
-    -t "0:0FC63DAF-8483-4772-8E79-3D69D8477DE4" \
-    -u "0:a52a4597-fa3a-4851-aefd-2fbe9f849079" \
-    "${NEW_DEVICE_ROOT}"
-sgdisk -v "${NEW_DEVICE_ROOT}"
-partx -u "${NEW_DEVICE_ROOT}"
-
-NEW_DEVICE_CHILD="$(fdisk -l "${NEW_DEVICE_ROOT}" | grep '^/dev' | cut -d' ' -f1 | head -n 1)"
-
-echo "[INFO] Move hassos-data from ${OLD_DEVICE_CHILD} to ${NEW_DEVICE_CHILD}"
-if ! dd if="${OLD_DEVICE_CHILD}" of="${NEW_DEVICE_CHILD}" status=none; then
-    echo "[ERROR] Data copy fails!"
-
-    # Reset new data partition
-    sgdisk -o "${NEW_DEVICE_ROOT}"
-    partx -u "${NEW_DEVICE_ROOT}"
+echo "[INFO] Moving data from ${OLD_DEVICE_CHILD} to ${NEW_DEVICE_CHILD}"
+if ! e2image -ra -p "${OLD_DEVICE_CHILD}" "${NEW_DEVICE_CHILD}"; then
+    echo "[ERROR] Copying data partition to external device failed!"
     exit 1
 fi
 
-echo "[INFO] Remove old hassos-data partition ${OLD_PART_NUM} / ${OLD_DEVICE_ROOT}"
-if sfdisk -dq "${OLD_DEVICE_ROOT}" | grep -q 'label: gpt'; then
-    sgdisk -d "${OLD_PART_NUM}" "${OLD_DEVICE_ROOT}"
-    sgdisk -v "${OLD_DEVICE_ROOT}"
+# At this point we have two partition with the same fs label. Make sure
+# to rename the internal partition so we won't mount it anymore.
+echo "[INFO] Rename old hassos-data partition ${OLD_DEVICE_CHILD}"
+e2label "${OLD_DEVICE_CHILD}" hassos-data-old
 
-else
-    sfdisk --delete "${OLD_DEVICE_ROOT}" "${OLD_PART_NUM}" --force
-    sfdisk -V "${OLD_DEVICE_ROOT}"
-fi
-
-echo "[INFO] fix filesystem & layout"
-
-# Fix filesystem
-e2fsck -y "${NEW_DEVICE_CHILD}"
-resize2fs -f "${NEW_DEVICE_CHILD}"
-
-# Fix partition layout
-partx -d "${OLD_DEVICE_CHILD}"
-partx -u "${OLD_DEVICE_ROOT}"
-partx -u "${NEW_DEVICE_ROOT}"
-
-echo "[INFO] Finish hassos data movement"
+echo "[INFO] Data move has been completed successfully"