add hypervisor

hosts/fw.cloonar.com/modules/hypervisor/baseline-qemu.nix

@@ -0,0 +1,12 @@
+{
+  imports = [ ./baseline.nix ];
+  fileSystems."/".device = "/dev/disk/by-label/nixos";
+  boot.initrd.availableKernelModules = [ "xhci_pci" "ehci_pci" "ahci" "usbhid" "usb_storage" "sd_mod" "virtio_balloon" "virtio_blk" "virtio_pci" "virtio_ring" ];
+  boot.loader = {
+    grub = {
+      version = 2;
+      device = "/dev/vda";
+    };
+    timeout = 0;
+  };
+}

hosts/fw.cloonar.com/modules/hypervisor/baseline.nix

@@ -0,0 +1,11 @@
+{
+  time.timeZone = "Europe/Vienna";
+  networking.hostName = "vm";
+  services.openssh.enable = true;
+  users.users.root.openssh.authorizedKeys.keys = [
+    "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDN/2SAFm50kraB1fepAizox/QRXxB7WbqVbH+5OPalDT47VIJGNKOKhixQoqhABHxEoLxdf/C83wxlCVlPV9poLfDgVkA3Lyt5r3tSFQ6QjjOJAgchWamMsxxyGBedhKvhiEzcr/Lxytnoz3kjDG8fqQJwEpdqMmJoMUfyL2Rqp16u+FQ7d5aJtwO8EUqovhMaNO7rggjPpV/uMOg+tBxxmscliN7DLuP4EMTA/FwXVzcFNbOx3K9BdpMRAaSJt4SWcJO2cS2KHA5n/H+PQI7nz5KN3Yr/upJN5fROhi/SHvK39QOx12Pv7FCuWlc+oR68vLaoCKYhnkl3DnCfc7A7"
+    "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIIRQuPqH5fdX3KEw7DXzWEdO3AlUn1oSmtJtHB71ICoH Generated By Termius"
+  ];
+
+  system.stateVersion = "22.05";
+}

hosts/fw.cloonar.com/modules/hypervisor/default.nix

@@ -0,0 +1,81 @@
+{ pkgs, ... }:
+let
+  hostNix = "server";
+  guests = {
+    git = {
+      memory = 16;
+      mac = "ed:22:4a:96:c3:01";
+      diskSize = 128;
+    };
+  };
+in
+{
+  boot.kernelModules = [ "kvm-amd" "kvm-intel" ];
+  virtualisation.libvirtd.enable = true;
+
+  systemd.services = lib.mapAttrs' (name: guest: lib.nameValuePair "libvirtd-guest-${name}" {
+    after = [ "libvirtd.service" ];
+    requires = [ "libvirtd.service" ];
+    wantedBy = [ "multi-user.target" ];
+    serviceConfig = {
+      Type = "oneshot";
+      RemainAfterExit = "yes";
+    };
+    script =
+      let
+        xml = pkgs.writeText "libvirt-guest-${name}.xml"
+          ''
+            <domain type="kvm">
+              <name>${name}</name>
+              <uuid>UUID</uuid>
+              <os>
+                <type>hvm</type>
+              </os>
+              <memory unit="GiB">${guest.memory}</memory>
+              <devices>
+                <disk type="volume">
+                  <source volume="guest-${name}"/>
+                  <target dev="vda" bus="virtio"/>
+                </disk>
+                <graphics type="spice" autoport="yes"/>
+                <input type="keyboard" bus="usb"/>
+                <interface type="direct">
+                  <source dev="${hostNic}" mode="bridge"/>
+                  <mac address="${guest.mac}"/>
+                  <model type="virtio"/>
+                </interface>
+              </devices>
+              <features>
+                <acpi/>
+              </features>
+            </domain>
+          '';
+      in
+        ''
+          if ! ${pkgs.libvirt}/bin/virsh vol-key 'guest-${name}' --pool guests &> /dev/null; then
+            ${pkgs.libvirt}/bin/virsh vol-create-as guests 'guest-${name}' '${guest.diskSize}GiB'
+            ${pkgs.qemu}/bin/qemu-img convert /etc/virt/base-images/baseline.qcow2 '/dev/${hostName}/guest-${name}'
+          fi
+          uuid="$(${pkgs.libvirt}/bin/virsh domuuid '${name}' || true)"
+          ${pkgs.libvirt}/bin/virsh define <(sed "s/UUID/$uuid/" '${xml}')
+          ${pkgs.libvirt}/bin/virsh start '${name}'
+        '';
+    preStop =
+      ''
+        ${pkgs.libvirt}/bin/virsh shutdown '${name}'
+        let "timeout = $(date +%s) + 10"
+        while [ "$(${pkgs.libvirt}/bin/virsh list --name | grep --count '^${name}$')" -gt 0 ]; do
+          if [ "$(date +%s)" -ge "$timeout" ]; then
+            # Meh, we warned it...
+            ${pkgs.libvirt}/bin/virsh destroy '${name}'
+          else
+            # The machine is still running, let's give it some time to shut down
+            sleep 0.5
+          fi
+        done
+      '';
+  }) guests;
+  
+  environment.etc."virt/base-images/baseline.qcow2".source = "${import ./image.nix args}/baseline.qcow2";
+
+}

hosts/fw.cloonar.com/modules/hypervisor/image.nix

@@ -0,0 +1,98 @@
+{ pkgs ? import <nixpkgs> {}, system ? builtins.currentSystem, ... }:
+let
+  config = (import <nixpkgs/nixos/lib/eval-config.nix> {
+    inherit system;
+    modules = [ {
+      imports = [ ./baseline-qemu.nix ];
+
+      # We want our template image to be as small as possible, but the deployed image should be able to be
+      # of any size. Hence we resize on the first boot.
+      systemd.services.resize-main-fs = {
+        wantedBy = [ "multi-user.target" ];
+        serviceConfig.Type = "oneshot";
+        script =
+          ''
+            # Resize main partition to fill whole disk
+            echo ", +" | ${pkgs.utillinux}/bin/sfdisk /dev/vda --no-reread -N 1
+            ${pkgs.parted}/bin/partprobe
+            # Resize filesystem
+            ${pkgs.e2fsprogs}/bin/resize2fs /dev/vda1
+          '';
+      };
+    } ];
+  }).config;
+in pkgs.vmTools.runInLinuxVM (
+  pkgs.runCommand "nixos-sun-baseline-image"
+    {
+      memSize = 768;
+      preVM =
+        ''
+          mkdir $out
+          diskImage=image.qcow2
+          ${pkgs.vmTools.qemu}/bin/qemu-img create -f qcow2 $diskImage 1G
+          mv closure xchg/
+        '';
+      postVM =
+        ''
+          echo compressing VM image...
+          ${pkgs.vmTools.qemu}/bin/qemu-img convert -c $diskImage -O qcow2 $out/baseline.qcow2
+        '';
+      buildInputs = [ pkgs.utillinux pkgs.perl pkgs.parted pkgs.e2fsprogs ];
+      exportReferencesGraph =
+        [ "closure" config.system.build.toplevel ];
+    }
+    ''
+      # Create the partition
+      parted /dev/vda mklabel msdos
+      parted /dev/vda -- mkpart primary ext4 1M -1s
+      . /sys/class/block/vda1/uevent
+      mknod /dev/vda1 b $MAJOR $MINOR
+
+      # Format the partition
+      mkfs.ext4 -L nixos /dev/vda1
+      mkdir /mnt
+      mount /dev/vda1 /mnt
+
+      for dir in dev proc sys; do
+        mkdir /mnt/$dir
+        mount --bind /$dir /mnt/$dir
+      done
+
+      storePaths=$(perl ${pkgs.pathsFromGraph} /tmp/xchg/closure)
+      echo filling Nix store...
+      mkdir -p /mnt/nix/store
+      set -f
+      cp -prd $storePaths /mnt/nix/store
+      # The permissions will be set up incorrectly if the host machine is not running NixOS
+      chown -R 0:30000 /mnt/nix/store
+
+      mkdir -p /mnt/etc/nix
+      echo 'build-users-group = ' > /mnt/etc/nix/nix.conf
+
+     # at least since nix-2.3.16 we need a root user in the chroot 
+     # or else `nix-store --load-db` will fail with "cannot figure out user name"
+     chroot /mnt ${pkgs.shadow}/bin/useradd -u 0 root
+
+      # Register the paths in the Nix database.
+      printRegistration=1 perl ${pkgs.pathsFromGraph} /tmp/xchg/closure | \
+          chroot /mnt ${config.nix.package.out}/bin/nix-store --load-db
+
+      # Create the system profile to allow nixos-rebuild to work.
+      chroot /mnt ${config.nix.package.out}/bin/nix-env \
+          -p /nix/var/nix/profiles/system --set ${config.system.build.toplevel}
+
+      # `nixos-rebuild' requires an /etc/NIXOS.
+      mkdir -p /mnt/etc/nixos
+      touch /mnt/etc/NIXOS
+
+      # `switch-to-configuration' requires a /bin/sh
+      mkdir -p /mnt/bin
+      ln -s ${config.system.build.binsh}/bin/sh /mnt/bin/sh
+
+      # Generate the GRUB menu.
+      chroot /mnt ${config.system.build.toplevel}/bin/switch-to-configuration boot
+
+      umount /mnt/{proc,dev,sys}
+      umount /mnt
+    ''
+)