podvm-mkosi: build s390x fedora image

Package system with mkosi and generate bootloader
with zipl

Signed-off-by: Lei Li <[email protected]>
Signed-off-by: Lei Li <[email protected]>

hack/build-s390x-image.sh

@@ -0,0 +1,85 @@
+#!/bin/bash
+
+set -euo pipefail
+
+pushd ../podvm-mkosi/build
+
+workdir=.
+tmp_img_path="${workdir}/tmp.qcow2"
+tmp_nbd=/dev/nbd1
+dst_mnt=./dst_mnt
+disksize=100G
+
+qemu-img create -f qcow2 "${tmp_img_path}" "${disksize}"
+
+modprobe nbd
+qemu-nbd --connect="${tmp_nbd}" "${tmp_img_path}"
+
+# Partition and format
+parted -a optimal "${tmp_nbd}" mklabel gpt \
+ mkpart boot ext4 1MiB 256MiB \
+ mkpart system 256MiB "${disksize}" \
+ set 1 boot on
+
+echo "Waiting for the two nbd partitions to show up"
+while true; do
+sleep 1
+[[ -e "${tmp_nbd}"p2 ]] && break
+done
+
+mke2fs -t ext4 -L boot "${tmp_nbd}"p1
+boot_uuid=$(blkid "${tmp_nbd}"p1 -s PARTUUID -o value)
+
+mke2fs -t ext4 -L system "${tmp_nbd}"p2
+system_uuid=$(blkid "${tmp_nbd}"p2 -s PARTUUID -o value)
+
+# Copy files
+mkdir -p "${dst_mnt}"
+mount "${tmp_nbd}p2" "${dst_mnt}"
+
+mkdir -p "${dst_mnt}"/boot
+mount -o norecovery "${tmp_nbd}"p1 "${dst_mnt}"/boot
+
+cp initrd.cpio.zst "${dst_mnt}"/boot/initrd.img
+cp system.vmlinuz "${dst_mnt}"/boot/vmlinuz
+
+src_mnt=system
+tar_opts=(--numeric-owner --preserve-permissions --acl --selinux --xattrs --xattrs-include='*' --sparse)
+tar -cf - "${tar_opts[@]}" --sort=none -C "${src_mnt}" . | tar -xf - "${tar_opts[@]}" --preserve-order -C "${dst_mnt}"
+
+cat <<END > "${dst_mnt}/etc/fstab"
+#This file was auto-generated
+PARTUUID=${system_uuid} / ext4 defaults 1 1
+PARTUUID=${boot_uuid} /boot ext4 norecovery 1 2
+END
+
+mount -t sysfs sysfs "${dst_mnt}/sys"
+mount -t proc proc "${dst_mnt}/proc"
+mount --bind /dev "${dst_mnt}/dev"
+
+# generate bootloader
+chroot "${dst_mnt}" zipl -V --targetbase "${tmp_nbd}" \
+ --targettype scsi \
+ --targetblocksize 512 \
+ --targetoffset 2048 \
+ --target /boot \
+ --image /boot/vmlinuz \
+ --ramdisk /boot/initrd.img \
+ --parameters "root=LABEL=system selinux=0 enforcing=0 audit=0 systemd.firstboot=off"
+
+umount "${dst_mnt}/dev"
+umount "${dst_mnt}/proc"
+umount "${dst_mnt}/sys"
+
+umount "${dst_mnt}/boot"
+umount "${dst_mnt}"
+
+qemu-nbd --disconnect "${tmp_nbd}"
+
+output_img_name="podvm-s390x.qcow2"
+qemu-img convert -O qcow2 -c "${tmp_img_path}" "${output_img_name}"
+
+output_img_path=$(realpath "${output_img_name}")
+echo "podvm image is generated: ${output_img_path}"
+
+popd

podvm-mkosi/Makefile

@@ -46,15 +46,25 @@ image:
  rm -rf resources/buildDebugImage
  rm -rf ./build
  @echo "Building image..."
+ifeq ($(ARCH),s390x)
+ mkosi --profile production.conf
+ ../hack/build-s390x-image.sh
+else
  nix develop ..#podvm-mkosi --command mkosi --environment=VARIANT_ID=production
+endif
 
 PHONY: image-debug
 image-debug:
  @echo "Enabling debug preset..."
  touch resources/buildDebugImage
  rm -rf ./build
  @echo "Building debug image..."
+ifeq ($(ARCH),s390x)
+ mkosi --profile debug.conf
+ ../hack/build-s390x-image.sh
+else
  nix develop ..#podvm-mkosi --command mkosi --environment=VARIANT_ID=debug
+endif
 
 PHONY: clean
 clean:

podvm-mkosi/README.md

@@ -75,3 +75,27 @@ reduce complexity of configuration and CI and shall not be seen as open to-dos.
 
 - Deployed images cannot be customized with cloud-init. Runtime configuration data is retrieved
  from IMDS via the project's `process-user-data` tool.
+
+## Build s390x image
+Since the [nix OS](https://nixos.org/download/#download-nix) does not support s390x, we can use the mkosi **ToolsTree** feature defined in `mkosi.conf` to download latest tools automatically:
+```
+[Host]
+ToolsTree=default
+```
+And install **mkosi** from the repository:
+```sh
+git clone -b v21 https://github.com/systemd/mkosi
+ln -s $PWD/mkosi/bin/mkosi /usr/local/bin/mkosi
+mkosi --version
+```
+Another issue is s390x does not support UEFI. Instead, we can first use **mkosi** to build non-bootable system files, then use **zipl** to generate the bootloader and finally create the bootable image.
+
+It requires a **s390x host** to build s390x image with make commands:
+```
+make fedora-binaries-builder
+make binaries
+make image
+# make image-debug
+```
+
+The final output is `build/podvm-s390x.qcow2`, which can be used as the Pod VM image in libvirt environment.

podvm-mkosi/mkosi.presets/initrd/mkosi.conf.d/fedora-s390x.conf

@@ -0,0 +1,10 @@
+[Match]
+Distribution=fedora
+
+Architecture=s390x
+
+[Content]
+Packages=kernel-core
+
+[Host]
+ToolsTree=default

podvm-mkosi/mkosi.presets/system/mkosi.conf.d/fedora-bootable.conf

@@ -0,0 +1,7 @@
+[Match]
+Distribution=fedora
+
+Architecture=!s390x
+
+[Content]
+Packages=systemd-boot

podvm-mkosi/mkosi.presets/system/mkosi.conf.d/fedora-s390x.conf

@@ -0,0 +1,18 @@
+[Match]
+Distribution=fedora
+
+Architecture=s390x
+
+[Content]
+Bootable=no
+Packages=s390utils
+ dhclient
+ NetworkManager
+ cloud-init
+ cloud-utils-growpart
+
+[Output]
+Format=directory
+
+[Host]
+ToolsTree=default

podvm-mkosi/mkosi.presets/system/mkosi.conf.d/fedora.conf

@@ -15,7 +15,6 @@ Packages=
  udev
  util-linux
  systemd
- systemd-boot
  systemd-networkd
  systemd-resolved
  dbus

podvm-mkosi/mkosi.presets/system/mkosi.finalize.chroot

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+
+set -euxo pipefail
+
+if [[ "${ARCHITECTURE}" == "s390x" ]]; then
+ # enable cloud-init services
+ systemctl enable cloud-init-local.service
+ systemctl enable cloud-init.service
+ systemctl enable cloud-config.service
+ systemctl enable cloud-final.service
+
+ # disable this service since we already have "NetworkManager-wait-online.service"
+ systemctl disable systemd-networkd-wait-online.service
+fi

podvm-mkosi/mkosi.profiles/debug.conf

@@ -0,0 +1,2 @@
+[Content]
+Environment=VARIANT_ID=debug

podvm-mkosi/mkosi.profiles/production.conf

@@ -0,0 +1,2 @@
+[Content]
+Environment=VARIANT_ID=production