Create disko ZFS configuration module

modules/default.nix

@@ -7,5 +7,6 @@
     ./random-alerts
     ./host-info.nix
     ./secrets.nix
+    ./mcl-disko
   ];
 }

modules/mcl-disko/default.nix

@@ -0,0 +1,196 @@
+{ withSystem, inputs, ... }:
+{
+  flake.modules.nixos.mcl-disko =
+    {
+      pkgs,
+      config,
+      lib,
+      ...
+    }:
+    with lib;
+    let
+      cfg = config.mcl.disko;
+    in
+    {
+      imports = [
+        inputs.disko.nixosModules.disko
+      ];
+      options.mcl.disko = {
+        enable = mkEnableOption "Enable Module";
+
+        legacyBoot = mkOption {
+          type = types.bool;
+          default = false;
+          example = true;
+          description = "Declare if the configuration is for a Hetzner server or not";
+        };
+
+        swapSize = mkOption {
+          type = types.str;
+          default = "32G";
+          example = "32768M";
+          description = "The size of the hard disk space used when RAM is full";
+        };
+
+        espSize = mkOption {
+          type = types.str;
+          default = "4G";
+          example = "4096M";
+          description = "The size of the hard disk space used for the ESP filesystem";
+        };
+
+        disks = mkOption {
+          type = types.listOf types.str;
+          default = [ ];
+          example = [
+            "/dev/disk/sda"
+            "/dev/disk/sdb"
+            "/dev/disk/sdc"
+          ];
+          description = "The disk partitions to be used when ZFS is being created";
+        };
+
+        disksNames = mkOption {
+          type = types.listOf types.str;
+          default = cfg.disks;
+          example = [
+            "sda"
+            "sdb"
+            "sdc"
+          ];
+          description = "The disk partitions names to be used when ZFS is being created";
+        };
+
+        zpool = {
+          name = mkOption {
+            type = types.str;
+            default = "zfs_root";
+            description = "The name of the ZFS Pool";
+          };
+
+          mode = mkOption {
+            type = types.enum [
+              "stripe"
+              "mirror"
+              "raidz1"
+              "raidz2"
+              "raidz3"
+            ];
+            default = "stripe";
+            description = "Set ZFS Pool redundancy - e.g. 'mirror', 'raidz1', etc.";
+          };
+
+          extraDatasets = mkOption {
+            type = types.attrsOf (
+              types.submodule (
+                { name, ... }:
+                {
+                  options = {
+                    mountpoint = mkOption {
+                      type = types.nullOr types.str;
+                      default = name;
+                      example = "/var/lib";
+                      description = "The ZFS dataset mountpoint";
+                    };
+
+                    type = mkOption {
+                      type = types.enum [
+                        "zfs_fs"
+                        "zfs_volume"
+                      ];
+                      default = "zfs_fs";
+                      description = "Type of ZFS dataset";
+                    };
+
+                    options = mkOption {
+                      type = types.attrs;
+                      default = { };
+                      example = {
+                        refreservation = "50G";
+                      };
+                      description = "";
+                    };
+
+                    snapshot = mkEnableOption "Whether to enable ZFS snapshots";
+
+                    refreservation = mkOption {
+                      type = types.nullOr types.str;
+                      default = null;
+                      description = "Size of reservations";
+                    };
+                  };
+                }
+              )
+            );
+            default = { };
+            example = {
+              "/opt".snapshot = false;
+              "/opt/downloads".snapshot = false;
+              "/opt/downloads/vm-images" = {
+                snapshot = false;
+                options = {
+                  quota = "120G";
+                };
+              };
+            };
+            description = "Extra ZFS Pool datasets";
+          };
+        };
+      };
+
+      config.disko =
+        let
+          makePrimaryZfsDisk = import ./primaryZfsPartition.nix;
+          makeSecondaryZfsDisk = import ./secondaryZfsPartition.nix;
+
+          first = builtins.head cfg.disks;
+          rest = builtins.tail cfg.disks;
+
+          firstDiskName = builtins.head cfg.disksNames;
+          restDisksNames = builtins.tail cfg.disksNames;
+
+          secondaryDisks = builtins.listToAttrs (
+            lib.zipListsWith (disk: diskName: {
+              name = diskName;
+              value =
+                if cfg.zpool.mode != "stripe" then
+                  makePrimaryZfsDisk {
+                    inherit disk lib;
+                    isSecondary = true;
+                    espSize = cfg.espSize;
+                    swapSize = cfg.swapSize;
+                    legacyBoot = cfg.legacyBoot;
+                    poolName = cfg.zpool.name;
+                  }
+                else
+                  makeSecondaryZfsDisk {
+                    poolName = cfg.zpool.name;
+                    inherit disk lib;
+                  };
+            }) rest restDisksNames
+          );
+
+        in
+        lib.mkIf cfg.enable {
+          devices = {
+            disk = secondaryDisks // {
+              "${firstDiskName}" = makePrimaryZfsDisk {
+                inherit lib;
+                disk = first;
+                isSecondary = false;
+                espSize = cfg.espSize;
+                swapSize = cfg.swapSize;
+                legacyBoot = cfg.legacyBoot;
+                poolName = cfg.zpool.name;
+              };
+            };
+            zpool = import ./zpool.nix {
+              poolName = cfg.zpool.name;
+              poolMode = cfg.zpool.mode;
+              poolExtraDatasets = cfg.zpool.extraDatasets;
+              inherit lib;
+            };
+          };
+        };
+    };
+}

modules/mcl-disko/primaryZfsPartition.nix

@@ -0,0 +1,95 @@
+{
+  lib,
+  disk,
+  isSecondary,
+  espSize,
+  swapSize,
+  legacyBoot,
+  poolName,
+}:
+{
+  type = "disk";
+  device = disk;
+  content =
+    {
+      type = if legacyBoot then "table" else "gpt";
+      partitions =
+        if !legacyBoot then
+          {
+            "ESP" = {
+              device = "${disk}-part1";
+              size = espSize;
+              type = "EF00";
+              content = {
+                type = "filesystem";
+                format = "vfat";
+                mountpoint = if isSecondary then null else "/boot";
+                mountOptions = [ "umask=0077" ];
+              };
+            };
+
+            "zfs" = {
+              device = "${disk}-part2";
+              end = "-${swapSize}";
+              type = "BF00";
+              content = {
+                type = "zfs";
+                pool = "${poolName}";
+              };
+            };
+
+            "swap" = {
+              device = "${disk}-part3";
+              size = swapSize;
+              content = {
+                type = "swap";
+                randomEncryption = true;
+              };
+            };
+          }
+        else
+          [
+            {
+              name = "boot";
+              start = "1MiB";
+              end = "2MiB";
+              part-type = "primary";
+              flags = [ "bios_grub" ];
+            }
+            {
+              name = "ESP";
+              start = "2MiB";
+              end = espSize;
+              bootable = true;
+              content = {
+                type = "filesystem";
+                format = "vfat";
+                mountpoint = if isSecondary then null else "/boot";
+              };
+            }
+            {
+              name = "zfs";
+              start = espSize;
+              end = "-${swapSize}";
+              part-type = "primary";
+              content = {
+                type = "zfs";
+                pool = "${poolName}";
+              };
+            }
+            {
+              name = "swap";
+              start = "-${swapSize}";
+              end = "100%";
+              part-type = "primary";
+              content = {
+                type = "swap";
+                randomEncryption = true;
+              };
+            }
+          ];
+    }
+    // lib.optionalAttrs legacyBoot {
+      format = "gpt";
+    };
+}

modules/mcl-disko/secondaryZfsPartition.nix

@@ -0,0 +1,22 @@
+{
+  lib,
+  poolName,
+  disk,
+}:
+{
+  type = "disk";
+  device = disk;
+  content = {
+    type = "gpt";
+    partitions = {
+      zfs = {
+        device = "${disk}-part1";
+        size = "100%";
+        content = {
+          type = "zfs";
+          pool = "${poolName}";
+        };
+      };
+    };
+  };
+}