From f5cc4b55e5adc8a19b1e986245f632e006226e01 Mon Sep 17 00:00:00 2001
From: matthewcroughan <matt@croughan.sh>
Date: Wed, 3 Jul 2024 19:53:13 +0100
Subject: [PATCH 1/3] make-disk-image: allow kernel to be overriden by disko
 configuration

This is especially useful when trying to build images for embedded systems such as the pi, which have a vendor kernel that can't be booted as part of the disko image builder process
---
 lib/make-disk-image.nix |  2 +-
 module.nix              | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/make-disk-image.nix b/lib/make-disk-image.nix
index a61e937..e1f7e36 100644
--- a/lib/make-disk-image.nix
+++ b/lib/make-disk-image.nix
@@ -10,7 +10,7 @@ let
   vmTools = pkgs.vmTools.override {
     rootModules = [ "9p" "9pnet_virtio" "virtio_pci" "virtio_blk" ] ++ nixosConfig.config.disko.extraRootModules;
     kernel = pkgs.aggregateModules
-      (with nixosConfig.config.boot.kernelPackages; [ kernel ]
+      (with nixosConfig.config.disko.imageBuilderKernelPackages; [ kernel ]
         ++ lib.optional (lib.elem "zfs" nixosConfig.config.disko.extraRootModules) zfs);
   };
   cleanedConfig = diskoLib.testLib.prepareDiskoConfig nixosConfig.config diskoLib.testLib.devices;
diff --git a/module.nix b/module.nix
index 8c8fbc3..33b58dc 100644
--- a/module.nix
+++ b/module.nix
@@ -10,6 +10,17 @@ let
 in
 {
   options.disko = {
+    imageBuilderKernel = lib.mkOption {
+      type = lib.types.package;
+    imageBuilderKernelPackages = lib.mkOption {
+      type = lib.types.attrs;
+      description = ''
+        the kernel used when building disk images via make-disk-image.nix.
+        Useful when the config's kernel won't boot in the image-builder.
+      '';
+      default = config.boot.kernelPackages;
+      example = lib.literalExpression "pkgs.linuxPackages_testing";
+    };
     extraRootModules = lib.mkOption {
       type = lib.types.listOf lib.types.str;
       description = ''

From de015d2a44632ea1102522e609c0beba0e57a18b Mon Sep 17 00:00:00 2001
From: matthewcroughan <matt@croughan.sh>
Date: Mon, 8 Jul 2024 20:11:00 +0100
Subject: [PATCH 2/3] make-disk-image: allow pkgs to be overriden by disko
 configuration

This is needed when the nixosConfig you're building for modifies nixpkgs options that lead to evaluation failing unnecessarily
---
 lib/make-disk-image.nix | 2 +-
 module.nix              | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/lib/make-disk-image.nix b/lib/make-disk-image.nix
index e1f7e36..9979b21 100644
--- a/lib/make-disk-image.nix
+++ b/lib/make-disk-image.nix
@@ -1,6 +1,6 @@
 { nixosConfig
 , diskoLib
-, pkgs ? nixosConfig.pkgs
+, pkgs ? nixosConfig.config.disko.imageBuilderPkgs
 , lib ? pkgs.lib
 , name ? "${nixosConfig.config.networking.hostName}-disko-images"
 , extraPostVM ? nixosConfig.config.disko.extraPostVM
diff --git a/module.nix b/module.nix
index 33b58dc..321cc0e 100644
--- a/module.nix
+++ b/module.nix
@@ -12,6 +12,15 @@ in
   options.disko = {
     imageBuilderKernel = lib.mkOption {
       type = lib.types.package;
+    imageBuilderPkgs = lib.mkOption {
+      type = lib.types.attrs;
+      description = ''
+        the pkgs instance used when building disk images via make-disk-image.nix.
+        Useful when the config's kernel won't boot in the image-builder.
+      '';
+      default = pkgs;
+      example = lib.literalExpression "pkgs";
+    };
     imageBuilderKernelPackages = lib.mkOption {
       type = lib.types.attrs;
       description = ''

From d8a1d5e1f0885d151801ef3e35251a475f53691e Mon Sep 17 00:00:00 2001
From: matthewcroughan <matt@croughan.sh>
Date: Mon, 8 Jul 2024 20:12:36 +0100
Subject: [PATCH 3/3] make-disk-image: allow vmTools qemu usage to be overriden
 by disko configuration

This is needed to prevent two layers of emulation when offering a build for a host running binfmt such as an x86 host trying to compile for aarch64 via binfmt
---
 lib/make-disk-image.nix |  1 +
 module.nix              | 12 ++++++++++--
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/lib/make-disk-image.nix b/lib/make-disk-image.nix
index 9979b21..c03676e 100644
--- a/lib/make-disk-image.nix
+++ b/lib/make-disk-image.nix
@@ -9,6 +9,7 @@
 let
   vmTools = pkgs.vmTools.override {
     rootModules = [ "9p" "9pnet_virtio" "virtio_pci" "virtio_blk" ] ++ nixosConfig.config.disko.extraRootModules;
+    customQemu = nixosConfig.config.disko.imageBuilderQemu;
     kernel = pkgs.aggregateModules
       (with nixosConfig.config.disko.imageBuilderKernelPackages; [ kernel ]
         ++ lib.optional (lib.elem "zfs" nixosConfig.config.disko.extraRootModules) zfs);
diff --git a/module.nix b/module.nix
index 321cc0e..d58f6ef 100644
--- a/module.nix
+++ b/module.nix
@@ -10,8 +10,16 @@ let
 in
 {
   options.disko = {
-    imageBuilderKernel = lib.mkOption {
-      type = lib.types.package;
+    imageBuilderQemu = lib.mkOption {
+      type = lib.types.nullOr lib.types.str;
+      description = ''
+        the qemu emulator string used when building disk images via make-disk-image.nix.
+        Useful when using binfmt on your build host, and wanting to build disk
+        images for a foreign architecture
+      '';
+      default = null;
+      example = lib.literalExpression "''${pkgs.qemu_kvm}/bin/qemu-system-aarch64";
+    };
     imageBuilderPkgs = lib.mkOption {
       type = lib.types.attrs;
       description = ''