Add rd.kiwi.install.retain_last deployment option

build-tests/x86/tumbleweed/test-image-disk/appliance.kiwi

@@ -1,11 +1,15 @@
 <?xml version="1.0" encoding="utf-8"?>
-
+<!-- OBS-Profiles: @BUILD_FLAVOR@ -->
 <image schemaversion="7.5" name="kiwi-test-image-disk">
     <description type="system">
         <author>Marcus Schäfer</author>
         <contact>[email protected]</contact>
         <specification>Disk test build</specification>
     </description>
+    <profiles>
+        <profile name="Standard" description="Standard Disk"/>
+        <profile name="Retain" description="Retain Last Partition"/>
+    </profiles>
     <preferences>
         <version>1.42.1</version>
         <packagemanager>zypper</packagemanager>
@@ -16,10 +20,13 @@
         <rpm-check-signatures>false</rpm-check-signatures>
         <bootsplash-theme>breeze</bootsplash-theme>
         <bootloader-theme>openSUSE</bootloader-theme>
+    </preferences>
+    <preferences profiles="Standard">
         <type image="oem" filesystem="btrfs" kernelcmdline="console=ttyS0" firmware="efi" installiso="true" bootpartition="false" btrfs_root_is_snapshot="true" installboot="install">
             <bootloader name="grub2" console="serial" timeout="10"/>
             <oemconfig>
                 <oem-unattended>true</oem-unattended>
+                <oem-swap>true</oem-swap>
                 <oem-swapsize>1024</oem-swapsize>
                 <oem-multipath-scan>false</oem-multipath-scan>
             </oemconfig>
@@ -28,8 +35,28 @@
             </systemdisk>
         </type>
     </preferences>
+    <preferences profiles="Retain">
+        <type image="oem" filesystem="btrfs" kernelcmdline="console=ttyS0 rd.kiwi.install.systemsize=all rd.kiwi.install.retain_last" firmware="efi" installiso="true" bootpartition="false" btrfs_root_is_snapshot="true" installboot="install" spare_part="0" spare_part_fs="ext4" spare_part_mountpoint="/home" spare_part_is_last="true">
+            <bootloader name="grub2" console="serial" timeout="10"/>
+            <oemconfig>
+                <oem-unattended>true</oem-unattended>
+                <oem-swap>true</oem-swap>
+                <oem-swapsize>512</oem-swapsize>
+                <!-- set root partition to a fixed value to keep address consistent -->
+                <oem-systemsize>2048</oem-systemsize>
+                <oem-multipath-scan>false</oem-multipath-scan>
+                <oem-resize>true</oem-resize>
+            </oemconfig>
+            <systemdisk>
+                <volume name="root"/>
+            </systemdisk>
+            <!-- whole disk must be big enough for fixed root + other -->
+            <size unit="G">3</size>
+        </type>
+    </preferences>
     <users>
         <user password="$1$wYJUgpM5$RXMMeASDc035eX.NbYWFl0" home="/root" name="root" groups="root"/>
+        <user password="$1$wYJUgpM5$RXMMeASDc035eX.NbYWFl0" home="/home/test-user" name="test-user" groups="users"/>
     </users>
     <repository type="rpm-md">
         <source path="obsrepositories:/"/>

build-tests/x86/tumbleweed/test-image-disk/config.sh

@@ -1,9 +1,22 @@
 #!/bin/bash
 set -ex
 
+declare kiwi_profiles=${kiwi_profiles}
+
 #======================================
 # Activate services
 #--------------------------------------
 systemctl enable sshd
 systemctl enable grub_config
 systemctl enable dracut_hostonly
+
+# Just in case the kiwi resizer is disabled in the system and
+# gets dropped from the initrd by the customer for some reason
+for profile in ${kiwi_profiles//,/ }; do
+    if [ "${profile}" = "Retain" ]; then
+        cat > /etc/fstab.script <<-EOF
+		sed -ie "s@/home ext4 defaults@/home ext4 x-systemd.growfs,defaults@" /etc/fstab
+        rm /etc/fstabe
+		EOF
+    fi
+done

doc/source/concept_and_workflow/customize_the_boot_process.rst

@@ -222,6 +222,17 @@ the available kernel boot parameters for these modules:
   Note that options starting with `rd.kiwi` are not passed to avoid
   side effects.
 
+``rd.kiwi.install.retain_last``
+  Instructs an OEM installation to retain the contents of the
+  last partition on the target disk. This setting is only useful
+  if the last partition does not belong to the main OS e.g. an
+  extra data partition added via the `spare_part` attribute in
+  the type setup of the image description. The implementation
+  also checks if the start address of the last partition on the
+  target disk matches with the start adress of the image to be
+  deployed. Only if they match the data on the last partition
+  can be retained.
+
 ``rd.kiwi.oem.luks.reencrypt``
   For OEM LUKS2 encrypted disk images. If set, reencrypts the disk
   prior an eventual resize and therefore creates a new key pool and

dracut/modules.d/55kiwi-dump/kiwi-dump-image.sh

@@ -330,15 +330,50 @@ function dump_image {
     local load_text="Loading ${image_basename}..."
     local title_text="Installation..."
     local dump
+    local parttable
+    local count_32k
+    local image_size
+    local count=0
+    local block_size=32k
+
+    # can we dump this
+    check_image_fits_target "${image_target}"
 
+    # select dump method
     if [ -n "${image_from_remote}" ];then
         dump=dump_remote_image
     else
         dump=dump_local_image
     fi
 
-    check_image_fits_target "${image_target}"
+    # setup blocks and blocksize to retain last
+    if getargbool 0 rd.kiwi.install.retain_last; then
+        if [ -n "${image_from_remote}" ];then
+            image_size=$((blocks * blocksize))
+            parttable=$(
+                fetch_remote_partition_table "${image_source}" "${image_size}"
+            )
+        else
+            parttable=$(
+                fetch_local_partition_table "${image_source}"
+            )
+        fi
+        if compatible_to_retain "${parttable}" "${image_target}"; then
+            count=$(get_disk_offset_retain_last_partition "${parttable}")
+        fi
+        if [ "${count}" -gt 0 ];then
+            block_size=$(get_sector_size_from_table_dump "${parttable}")
+            count_32k=$(
+                optimize_count_for_32k_blocksize "${block_size}" "${count}"
+            )
+            if [ ! "${count}" = "${count_32k}" ];then
+                count="${count_32k}"
+                block_size=32k
+            fi
+        fi
+    fi
 
+    # last chance to stop us
     if [ "${kiwi_oemunattended}" = "false" ];then
         local ack_dump_text="Destroying ALL data on ${image_target}, continue ?"
         if ! run_dialog --yesno "\"${ack_dump_text}\"" 7 80; then
@@ -347,48 +382,157 @@ function dump_image {
         fi
     fi
 
+    # deploy
     echo "${load_text} [${image_target}]..."
     if command -v pv &>/dev/null && [ "${kiwi_oemsilentinstall}" = "false" ]
     then
         # dump with dialog based progress information
         setup_progress_fifo ${progress}
-        eval "${dump}" "${image_source}" "${image_target}" "${progress}" &
+        eval \
+            "${dump}" \
+            "${image_source}" \
+            "${image_target}" \
+            "${count}" \
+            "${block_size}" \
+            "${progress}" \
+        &
         run_progress_dialog "${load_text}" "${title_text}"
     else
         # dump with silently blocked console
-        if ! eval "${dump}" "${image_source}" "${image_target}"; then
+        if ! eval \
+            "${dump}" \
+            "${image_source}" \
+            "${image_target}" \
+            "${count}" \
+            "${block_size}"
+        then
             report_and_quit "Failed to install image"
         fi
     fi
 }
 
+function fetch_local_partition_table {
+    local image_source=$1
+    local parttable=/tmp/parttable
+    sfdisk -d "${image_source}" > "${parttable}" 2>/dev/null
+    echo "${parttable}"
+}
+
+function fetch_remote_partition_table {
+    local image_source=$1
+    local image_size=$2
+    local parttable=/tmp/parttable
+    dd if=/dev/zero of=/tmp/table bs=1 count=0 seek="${image_size}" &>/dev/null
+    fetch_file "${image_source}" 2>/dev/null | dd of=/tmp/table bs=512 count=1 conv=notrunc &>/dev/null
+    sfdisk -d /tmp/table > "${parttable}" 2>/dev/null
+    echo "${parttable}"
+}
+
+function get_sector_size_from_table_dump {
+    local parttable=$1
+    sector_size=$(grep sector-size: "${parttable}" | cut -f2 -d:)
+    echo "${sector_size}"
+}
+
+function compatible_to_retain {
+    local parttable=$1
+    local image_target=$2
+    local source_start
+    local target_start
+    source_start=$(
+        tail -n 1 "${parttable}" | cut -f2 -d= | cut -f1 -d,
+    )
+    target_start=$(
+        sfdisk -d "${image_target}" 2>/dev/null |\
+        tail -n 1 | cut -f2 -d= | cut -f1 -d,
+    )
+    if [ -z "${source_start}" ] || [ -z "${target_start}" ];then
+        # no partition information for either source or target
+        # broken or net new deployment on empty disk
+        touch /tmp/retain_not_applicable
+        return 1
+    fi
+    if [ ! "${source_start}" = "${target_start}" ];then
+        report_and_quit "Cannot retain partition, start address mismatch"
+    fi
+    return 0
+}
+
+function get_disk_offset_retain_last_partition {
+    local parttable=$1
+    local next_to_last
+    local start
+    local size
+    local offset
+    next_to_last=$(tail -n 2 "${parttable}" | head -n 1)
+    if [ -n "${next_to_last}" ];then
+        start=$(echo "${next_to_last}" | cut -f2 -d= | cut -f1 -d,)
+        size=$(echo "${next_to_last}" | cut -f3 -d= | cut -f1 -d,)
+        offset=$((start + size))
+        echo "${offset}"
+    else
+        echo 0
+    fi
+}
+
+function optimize_count_for_32k_blocksize {
+    local block_size=$1
+    local count=$2
+    local dump_bytes
+    dump_bytes=$((block_size * count))
+    if [ $((dump_bytes % 32768)) -eq 0 ];then
+        # dump_bytes is a multiple of 32k, use it for better I/O performance
+        count=$((dump_bytes / 32768))
+    fi
+    echo "${count}"
+}
+
 function dump_local_image {
     local image_source=$1
     local image_target=$2
-    local progress=$3
+    local count=$3
+    local block_size=$4
+    local progress=$5
+    if [ "${count}" -gt 0 ];then
+        count="count=${count}"
+    else
+        unset count
+    fi
+    # shellcheck disable=SC2086
     if [ -e "${progress}" ];then
         (
-            pv -n "${image_source}" | dd bs=32k of="${image_target}" &>/dev/null
+            pv -n "${image_source}" |\
+            dd bs="${block_size}" ${count} of="${image_target}" &>/dev/null
         ) 2>"${progress}"
     else
-        dd if="${image_source}" bs=32k of="${image_target}" &>/dev/null
+        dd \
+            if="${image_source}" bs="${block_size}" ${count} \
+            of="${image_target}" &>/dev/null
     fi
 }
 
 function dump_remote_image {
     local image_source=$1
     local image_target=$2
-    local progress=$3
+    local count=$3
+    local block_size=$4
+    local progress=$5
     local image_size
     image_size=$((blocks * blocksize))
+    if [ "${count}" -gt 0 ];then
+        count="count=${count}"
+    else
+        unset count
+    fi
+    # shellcheck disable=SC2086
     if [ -e "${progress}" ];then
         (
             fetch_file "${image_source}" "${image_size}" |\
-                dd bs=32k of="${image_target}" &>/dev/null
+                dd bs="${block_size}" ${count} of="${image_target}" &>/dev/null
         ) 2>"${progress}"
     else
         fetch_file "${image_source}" |\
-            dd bs=32k of="${image_target}" &>/dev/null
+            dd bs="${block_size}" ${count} of="${image_target}" &>/dev/null
     fi
 }
 
@@ -406,6 +550,13 @@ function check_image_integrity {
         # no verification wanted
         return
     fi
+    if getargbool 0 rd.kiwi.install.retain_last; then
+        if [ ! -e /tmp/retain_not_applicable ];then
+            # no verification possible as only a portion of
+            # the image got deployed intentionally
+            return
+        fi
+    fi
     if command -v pv &>/dev/null && [ "${kiwi_oemsilentverify}" = "false" ]
     then
         # verify with dialog based progress information