chore(marr): add disko config

hosts/default.nix

@@ -13,7 +13,10 @@ in
     (mkSystem' {
       hostname = "marr";
       system = "x86_64-linux";
-      extraModules = [ inputs.agenix.nixosModules.default ];
+      extraModules = [
+        inputs.disko.nixosModules.disko
+        inputs.agenix.nixosModules.default
+      ];
     })
 
     (mkSystem' {

hosts/marr/disko.nix

@@ -0,0 +1,42 @@
+{ lib, ... }:
+let
+  inherit (lib.my.disko) mkBoot mkSwap mkRoot;
+in
+{
+  disko.devices = {
+    disk.builtin = {
+      device = "/dev/nvme0n1";
+      type = "disk";
+      content = {
+        type = "gpt";
+        partitions = {
+          ESP = mkBoot "1G";
+          luks = {
+            size = "100%";
+            content = {
+              type = "luks";
+              name = "crypt";
+              settings = {
+                keyFile = "/tmp/secret.key";
+                allowDiscards = true;
+              };
+              content = {
+                type = "lvm_pv";
+                vg = "pool";
+              };
+            };
+          };
+        };
+      };
+    };
+    lvm_vg = {
+      pool = {
+        type = "lvm_vg";
+        lvs = {
+          swap = mkSwap "32G";
+          root = mkRoot "100%" "ext4";
+        };
+      };
+    };
+  };
+}

parts/lib/functions.nix

@@ -79,4 +79,34 @@ in
       inherit (lib.strings) sanitizeDerivationName;
     in
     str: (sanitizeDerivationName (lib.toLower str));
+
+  disko = {
+    mkBoot = size: {
+      size = size;
+      type = "EF00";
+      content = {
+        type = "filesystem";
+        format = "vfat";
+        mountpoint = "/boot";
+        mountOptions = [ "umask=0077" ];
+      };
+    };
+    mkSwap = size: {
+      size = "32G";
+      content = {
+        type = "swap";
+        randomEncryption = true;
+        priority = 100;
+      };
+    };
+    mkRoot = size: format: {
+      inherit size;
+      content = {
+        inherit format;
+        type = "filesystem";
+        mountpoint = "/";
+        mountOptions = [ "defaults" ];
+      };
+    };
+  };
 }