Add --storage-total-size-mb option to mender-convert tool

storage-total-size-mb option allow user to define
the overall Mender image size, i.e. adjust it to
user's own needs or just to SD card size.

Issues: MEN-2242

Changelog: Title

Signed-off-by: Adam Podogrocki <a.podogrocki@gmail.com>

convert-stage-3.sh

@@ -9,6 +9,7 @@ build_log=$output_dir/build.log
 
 sudo dd if=${output_dir}/rootfs.img of=/dev/mapper/${rootfs_mapping} bs=8M conv=sparse >> "$build_log" 2>&1
 sync
+sudo resize2fs /dev/mapper/${rootfs_mapping} >> "$build_log" 2>&1
 # Check Linux ext4 file system just in case.
 sudo fsck.ext4 -fp /dev/mapper/${rootfs_mapping} >> "$build_log" 2>&1
 # Make sure the rootfs partition's label follows Mender naming convention.

mender-convert

@@ -35,8 +35,8 @@ Expert commands:
 Options: [-r|--raw-disk-image | -m|--mender-disk-image | -s|--data-part-size-mb |
           -d|--device-type | -p|--rootfs-partition-id | -i|--demo-host-ip |
           -c|--server-cert | -u|--server-url | -t|--tenant-token |
-          -g|--mender-client -b|--bootloader-toolchain | -a|--artifact-name |
-          -k|--keep | -v|--version]
+          -g|--mender-client | -b|--bootloader-toolchain | -a|--artifact-name |
+          -e|--storage-total-size-mb | -k|--keep | -v|--version]
 
         raw-disk-image        - raw disk embedded Linux (Debian, Raspbian,
                                 Ubuntu, etc.) image path
@@ -54,6 +54,8 @@ Options: [-r|--raw-disk-image | -m|--mender-disk-image | -s|--data-part-size-mb
         mender-client         - Mender client binary
         bootloader-toolchain  - GNU Arm Embedded Toolchain
         artifact-name         - Mender artifact name
+        storage-total-size-mb - total storage size in MB; default value 8000MB;
+                                it is used to calculate the rootfs final size
         keep                  - keep intermediate files in output directory
         version               - print the version
 
@@ -146,9 +148,6 @@ fi
 
 tool_dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
-# Default 'data' partition size in MiB.
-data_part_size_mb=128
-
 mender_disk_image=
 raw_disk_image=
 device_type=
@@ -282,6 +281,12 @@ do_raw_disk_image_create_partitions() {
   calculate_mender_disk_size ${partition_alignment} mender_disk_sizes \
                              mender_disk_counts mender_disk_image_size
 
+  mender_image_size_to_total_storage_size ${mender_disk_counts} \
+          mender_disk_image_size ${storage_total_size_mb} \
+          mender_disk_sizes
+  rc=$?
+  [ $rc -eq 0 ] || { return 1; }
+
   if [[ ${raw_disk_counts} -gt 1 ]]; then
     log "\tExtracting boot partition from raw disk image."
 
@@ -744,6 +749,10 @@ while (( "$#" )); do
       tenant_token=$2
       shift 2
       ;;
+    -e | --storage-total-size-mb)
+      storage_total_size_mb=$2
+      shift 2
+      ;;
     -k | --keep)
       keep="-k"
       shift 1
@@ -772,7 +781,11 @@ while (( "$#" )); do
 done
 
 [ -z "${data_part_size_mb}" ] && \
-    { log "Default 'data' partition size set to 128MB"; data_part_size_mb=128; }
+    { log "*** Data partition size set to default value: 128MB ***"; \
+      data_part_size_mb=$DATA_PART_SIZE_MB; }
+[ -z "${storage_total_size_mb}" ] && \
+    { log "*** Total storage size set to default value: 8GB ***"; \
+      storage_total_size_mb=$STORAGE_TOTAL_SIZE_MB; }
 
 eval set -- "$PARAMS"
 

mender-convert-functions.sh

@@ -8,6 +8,14 @@ declare -i vfat_storage_offset
 PART_ALIGN_4MB=4194304
 PART_ALIGN_8MB=8388608
 
+# Default 'data' partition size in MiB.
+declare -i data_part_size_mb
+# Default total storage size in MiB.
+declare -i storage_total_size_mb
+
+DATA_PART_SIZE_MB=128
+STORAGE_TOTAL_SIZE_MB=8000
+
 # Number of required heads in a final image.
 declare -i -r heads=255
 # Number of required sectors in a final image.
@@ -384,6 +392,77 @@ calculate_mender_disk_size() {
   eval $rvar_sdimgsize="'$sdimgsize'"
 }
 
+# Takes following arguments:
+#
+#  $1 - number of partition of the Mender image
+#  $2 - calculated total size of the Mender image in bytes
+#  $3 - expected total size of the Mender image in mb
+#  $4 - array of partitions' sizes for Mender image
+#
+#  Returns:
+#
+#  Size of the rootfs partition updated and adjusted to total storage size
+#
+mender_image_size_to_total_storage_size() {
+  local count=$1
+  local rvar_image_size=$2
+  local -n image_size_bytes=$2
+  local storage_size_mb=$3
+
+  local _mender_sizes=$(declare -p $4)
+  eval "declare -A mender_sizes="${_mender_sizes#*=}
+
+  shift 3
+  local rvar_array=($@)
+
+  local image_size_mb=$(( (($image_size_bytes / 1024) / 1024) ))
+
+  log "\tAdjust Mender disk image size to the total storage size (${storage_size_mb}MB)."
+
+  if [ $image_size_mb -gt $storage_size_mb ]; then
+    log "\tDefined total storage size of ${3}MB is too small."
+    log "\tMinimal required storage is ${image_size_mb}MB. Aborting."
+    return 1
+  elif [ $image_size_mb -eq $storage_size_mb ]; then
+    # Simply continue.
+    log "\tCalculated Mender image size exactly fits the defined total storage."
+    return 0
+  fi
+
+  # Get spare space for rootfs a/b partitions (in sectors).
+  local sector_size=${mender_sizes[sector_size]}
+  local image_size_s=$(( $image_size_bytes / $sector_size ))
+  local storage_size_bytes=$(( ($storage_size_mb * 1024 * 1024) ))
+  local storage_size_s=$(( $storage_size_bytes / $sector_size ))
+  local rootfs_overplus_bytes=0
+
+  local spare_storage_bytes=$(( $storage_size_bytes - $image_size_bytes ))
+
+  if [ $(($spare_storage_bytes % 2)) -ne 0 ]; then
+    log "\tAdditional space for rootfs partitions not divisible by 2.\
+         \n\tFinal image will be smaller than ${storage_size_mb}MB"
+  fi
+  rootfs_overplus_bytes=$(( $spare_storage_bytes / 2 ))
+
+  local reminder=$(( ${rootfs_overplus_bytes} % ${partition_alignment} ))
+  if [ $reminder -ne 0 ]; then
+    log "\tAdditional space for rootfs partitions not aligned.\
+         \n\tFinal image will be smaller than ${storage_size_mb}MB"
+  fi
+  rootfs_overplus_bytes=$(($rootfs_overplus_bytes - $reminder))
+  rootfs_overplus_s=$(( $rootfs_overplus_bytes / $sector_size ))
+
+  local prootfs_size=${mender_sizes[prootfs_size]}
+  prootfs_size=$(( $prootfs_size + $rootfs_overplus_s ))
+
+  image_size_bytes=$(( $image_size_bytes + 2 * $rootfs_overplus_bytes ))
+
+  eval $rvar_array[prootfs_size]="'$prootfs_size'"
+  eval $rvar_image_size="'$image_size_bytes'"
+
+  return 0
+}
+
 # Takes following arguments:
 #
 #  $1 - raw disk image