nixos/virtualisation/linode-image: init (#155426)

maintainers/maintainer-list.nix

···
     githubId = 25618740;
     name = "Vincent Cui";
   };
+  houstdav000 = {
+    email = "[e-mail]";
+    github = "houstdav000";
+    githubId = 17628961;
+    matrix = "@houstdav000:gh0st.ems.host";
+    name = "David Houston";
+  };
   hoverbear = {
     email = "[e-mail]";
     matrix = "@hoverbear:matrix.org";

nixos/doc/manual/from_md/release-notes/rl-2211.section.xml

···
       </listitem>
       <listitem>
         <para>
+          An image configuration and generator has been added for Linode
+          images, largely based on the present GCE configuration and
+          image.
+        </para>
+      </listitem>
+      <listitem>
+        <para>
           <literal>hardware.nvidia</literal> has a new option
           <literal>open</literal> that can be used to opt in the
           opensource version of NVIDIA kernel driver. Note that the

nixos/doc/manual/release-notes/rl-2211.section.md

···
 
 - OpenSSL now defaults to OpenSSL 3, updated from 1.1.1.
 
+- An image configuration and generator has been added for Linode images, largely based on the present GCE configuration and image.
+
 - `hardware.nvidia` has a new option `open` that can be used to opt in the opensource version of NVIDIA kernel driver. Note that the driver's support for GeForce and Workstation GPUs is still alpha quality, see [NVIDIA Releases Open-Source GPU Kernel Modules](https://developer.nvidia.com/blog/nvidia-releases-open-source-gpu-kernel-modules/) for the official announcement.
 
 <!-- To avoid merge conflicts, consider adding your item at an arbitrary place in the list instead. -->

nixos/modules/virtualisation/linode-config.nix

···
+{ config, lib, pkgs, ... }:
+with lib;
+{
+  imports = [ ../profiles/qemu-guest.nix ];
+
+  services.openssh = {
+    enable = true;
+
+    permitRootLogin = "prohibit-password";
+    passwordAuthentication = mkDefault false;
+  };
+
+  networking = {
+    usePredictableInterfaceNames = false;
+    useDHCP = false;
+    interfaces.eth0 = {
+      useDHCP = true;
+
+      # Linode expects IPv6 privacy extensions to be disabled, so disable them
+      # See: https://www.linode.com/docs/guides/manual-network-configuration/#static-vs-dynamic-addressing
+      tempAddress = "disabled";
+    };
+  };
+
+  # Install diagnostic tools for Linode support
+  environment.systemPackages = with pkgs; [
+    inetutils
+    mtr
+    sysstat
+  ];
+
+  fileSystems."/" = {
+    fsType = "ext4";
+    device = "/dev/sda";
+    autoResize = true;
+  };
+
+  swapDevices = mkDefault [{ device = "/dev/sdb"; }];
+
+  # Enable LISH and Linode Booting w/ GRUB
+  boot = {
+    # Add Required Kernel Modules
+    # NOTE: These are not documented in the install guide
+    initrd.availableKernelModules = [
+      "virtio_pci"
+      "virtio_scsi"
+      "ahci"
+      "sd_mod"
+    ];
+
+    # Set Up LISH Serial Connection
+    kernelParams = [ "console=ttyS0,19200n8" ];
+    kernelModules = [ "virtio_net" ];
+
+    loader = {
+      # Increase Timeout to Allow LISH Connection
+      # NOTE: The image generator tries to set a timeout of 0, so we must force
+      timeout = lib.mkForce 10;
+
+      grub = {
+        enable = true;
+        version = 2;
+        forceInstall = true;
+        device = "nodev";
+
+        # Allow serial connection for GRUB to be able to use LISH
+        extraConfig = ''
+          serial --speed=19200 --unit=0 --word=8 --parity=no --stop=1;
+          terminal_input serial;
+          terminal_output serial
+        '';
+      };
+    };
+  };
+}

nixos/modules/virtualisation/linode-image.nix

···
+{ config, lib, pkgs, ... }:
+
+with lib;
+let
+  cfg = config.virtualisation.linodeImage;
+  defaultConfigFile = pkgs.writeText "configuration.nix" ''
+    _: {
+      imports = [
+        <nixpkgs/nixos/modules/virtualisation/linode-image.nix>
+      ];
+    }
+  '';
+in
+{
+  imports = [ ./linode-config.nix ];
+
+  options = {
+    virtualisation.linodeImage.diskSize = mkOption {
+      type = with types; either (enum (singleton "auto")) ints.positive;
+      default = "auto";
+      example = 1536;
+      description = ''
+        Size of disk image in MB.
+      '';
+    };
+
+    virtualisation.linodeImage.configFile = mkOption {
+      type = with types; nullOr str;
+      default = null;
+      description = ''
+        A path to a configuration file which will be placed at `/etc/nixos/configuration.nix`
+        and be used when switching to a new configuration.
+        If set to `null`, a default configuration is used, where the only import is
+        `<nixpkgs/nixos/modules/virtualisation/linode-image.nix>`
+      '';
+    };
+
+    virtualisation.linodeImage.compressionLevel = mkOption {
+      type = types.ints.between 1 9;
+      default = 6;
+      description = ''
+        GZIP compression level of the resulting disk image (1-9).
+      '';
+    };
+  };
+
+  config = {
+    system.build.linodeImage = import ../../lib/make-disk-image.nix {
+      name = "linode-image";
+      # NOTE: Linode specifically requires images to be `gzip`-ed prior to upload
+      # See: https://www.linode.com/docs/products/tools/images/guides/upload-an-image/#requirements-and-considerations
+      postVM = ''
+        ${pkgs.gzip}/bin/gzip -${toString cfg.compressionLevel} -c -- $diskImage > \
+        $out/nixos-image-${config.system.nixos.label}-${pkgs.stdenv.hostPlatform.system}.img.gz
+        rm $diskImage
+      '';
+      format = "raw";
+      partitionTableType = "none";
+      configFile = if cfg.configFile == null then defaultConfigFile else cfg.configFile;
+      inherit (cfg) diskSize;
+      inherit config lib pkgs;
+    };
+  };
+
+  meta.maintainers = with maintainers; [ houstdav000 ];
+}