nixos-modules/microvm/options: move all user-input options here

so they end up in the doc
astro · Jan 9, 2025 · 3394c37 · 3394c37
1 parent 70db31a
commit 3394c37
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Showing 3 changed files with 94 additions and 93 deletions.
diff --git a/nixos-modules/microvm/optimization.nix b/nixos-modules/microvm/optimization.nix
@@ -13,56 +13,35 @@ let
     ) config.microvm.shares;
 
 in
-{
-  options.microvm.optimize = {
-    enable = lib.mkOption {
-      description = ''
-        Enables some optimizations by default to closure size and startup time:
-          - defaults documentation to off
-          - defaults to using systemd in initrd
-          - use systemd-networkd
-          - disables systemd-network-wait-online
-          - disables NixOS system switching if the host store is not mounted
-
-        This takes a few hundred MB off the closure size, including qemu,
-        allowing for putting MicroVMs inside Docker containers.
-      '';
-
-      type = lib.types.bool;
-      default = true;
-    };
-  };
-
-  config = lib.mkIf (cfg.guest.enable && cfg.optimize.enable) {
-    # The docs are pretty chonky
-    documentation.enable = lib.mkDefault false;
-
-    # Use systemd initrd for startup speed.
-    # TODO: error mounting /nix/store on crosvm, kvmtool
-    boot.initrd.systemd.enable = lib.mkDefault (
-      builtins.elem cfg.hypervisor [
-        "qemu"
-        "cloud-hypervisor"
-        "firecracker"
-        "stratovirt"
-      ]);
-
-    nixpkgs.overlays = [
-      (final: prev: {
-        stratovirt = prev.stratovirt.override { gtk3 = null; };
-      })
-    ];
-
-    # networkd is used due to some strange startup time issues with nixos's
-    # homegrown dhcp implementation
-    networking.useNetworkd = lib.mkDefault true;
-    # Due to a bug in systemd-networkd: https://github.com/systemd/systemd/issues/29388
-    # we cannot use systemd-networkd-wait-online.
-    systemd.network.wait-online.enable = lib.mkDefault false;
-
-    # Exclude switch-to-configuration.pl from toplevel.
-    system = lib.optionalAttrs (options.system ? switch && !canSwitchViaSsh) {
-      switch.enable = lib.mkDefault false;
-    };
+lib.mkIf (cfg.guest.enable && cfg.optimize.enable) {
+  # The docs are pretty chonky
+  documentation.enable = lib.mkDefault false;
+
+  # Use systemd initrd for startup speed.
+  # TODO: error mounting /nix/store on crosvm, kvmtool
+  boot.initrd.systemd.enable = lib.mkDefault (
+    builtins.elem cfg.hypervisor [
+      "qemu"
+      "cloud-hypervisor"
+      "firecracker"
+      "stratovirt"
+    ]);
+
+  nixpkgs.overlays = [
+    (final: prev: {
+      stratovirt = prev.stratovirt.override { gtk3 = null; };
+    })
+  ];
+
+  # networkd is used due to some strange startup time issues with nixos's
+  # homegrown dhcp implementation
+  networking.useNetworkd = lib.mkDefault true;
+  # Due to a bug in systemd-networkd: https://github.com/systemd/systemd/issues/29388
+  # we cannot use systemd-networkd-wait-online.
+  systemd.network.wait-online.enable = lib.mkDefault false;
+
+  # Exclude switch-to-configuration.pl from toplevel.
+  system = lib.optionalAttrs (options.system ? switch && !canSwitchViaSsh) {
+    switch.enable = lib.mkDefault false;
   };
 }
diff --git a/nixos-modules/microvm/options.nix b/nixos-modules/microvm/options.nix
@@ -17,6 +17,23 @@ in
       '';
     };
 
+    optimize.enable = lib.mkOption {
+      description = ''
+        Enables some optimizations by default to closure size and startup time:
+          - defaults documentation to off
+          - defaults to using systemd in initrd
+          - use systemd-networkd
+          - disables systemd-network-wait-online
+          - disables NixOS system switching if the host store is not mounted
+
+        This takes a few hundred MB off the closure size, including qemu,
+        allowing for putting MicroVMs inside Docker containers.
+      '';
+
+      type = lib.types.bool;
+      default = true;
+    };
+
     cpu = mkOption {
       type = with types; nullOr str;
       default = null;
@@ -519,14 +536,55 @@ in
       defaultText = literalExpression ''"config.microvm.runner.''${config.microvm.hypervisor}"'';
     };
 
-    # TODO: microvm-* as well?
     binScripts = mkOption {
       description = ''
         Script snippets that end up in the runner package's bin/ directory
       '';
       default = {};
       type = with types; attrsOf lines;
     };
+
+    storeDiskType = mkOption {
+      type = types.enum [ "squashfs" "erofs" ];
+      description = ''
+        Boot disk file system type: squashfs is smaller, erofs is supposed to be faster.
+
+        Defaults to erofs, unless the NixOS hardened profile is detected.
+      '';
+    };
+
+    storeDiskErofsFlags = mkOption {
+      type = with types; listOf str;
+      description = ''
+        Flags to pass to mkfs.erofs
+
+        Omit `"-Efragments"` and `"-Ededupe"` to enable multi-threading.
+      '';
+      default =
+        [ "-zlz4hc" ]
+        ++
+        lib.optional (kernelAtLeast "5.16") "-Eztailpacking"
+        ++
+        lib.optionals (kernelAtLeast "6.1") [
+          # not implemented with multi-threading
+          "-Efragments"
+          "-Ededupe"
+        ];
+      defaultText = lib.literalExpression ''
+        [ "-zlz4hc" ]
+          ++ lib.optional (kernelAtLeast "5.16") "-Eztailpacking"
+          ++ lib.optionals (kernelAtLeast "6.1") [
+          "-Efragments"
+          "-Ededupe"
+        ]
+        '';
+    };
+
+    storeDiskSquashfsFlags = mkOption {
+      type = with types; listOf str;
+      description = "Flags to pass to gensquashfs";
+      default = [ "-c" "zstd" "-j" "$NIX_BUILD_CORES" ];
+    };
   };
 
   config = lib.mkMerge [ {

diff --git a/nixos-modules/microvm/store-disk.nix b/nixos-modules/microvm/store-disk.nix
@@ -37,47 +37,11 @@ let
 
 in
 {
-  options.microvm = with lib; {
-    storeDiskType = mkOption {
-      type = types.enum [ "squashfs" "erofs" ];
-      description = ''
-        Boot disk file system type: squashfs is smaller, erofs is supposed to be faster.
-      '';
-    };
-
-    storeDiskErofsFlags = mkOption {
-      type = with types; listOf str;
-      default =
-        [ "-zlz4hc" ]
-        ++
-        lib.optional (kernelAtLeast "5.16") "-Eztailpacking"
-        ++
-        lib.optionals (kernelAtLeast "6.1") [
-          # not implemented with multi-threading
-          "-Efragments"
-          "-Ededupe"
-        ];
-      defaultText = lib.literalExpression ''
-        [ "-zlz4hc" ]
-          ++ lib.optional (kernelAtLeast "5.16") "-Eztailpacking"
-          ++ lib.optionals (kernelAtLeast "6.1") [
-          "-Efragments"
-          "-Ededupe"
-        ]
-        '';
-    };
-
-    storeDiskSquashfsFlags = mkOption {
-      type = with types; listOf str;
-      default = [ "-c" "zstd" "-j" "$NIX_BUILD_CORES" ];
-    };
-
-    storeDisk = mkOption {
-      type = types.path;
-      description = ''
-        Generated
-      '';
-    };
+  options.microvm.storeDisk = with lib; mkOption {
+    type = types.path;
+    description = ''
+      Generated
+    '';
   };
 
   config = lib.mkMerge [