Enable nvidia nix-required-mounts

This allows running derivations which depend on cuda runtime without
breaking the sandbox. We only need to add `requiredSystemFeatures = [ "cuda" ];`
to the derivation.

m/fox/configuration.nix

@@ -5,6 +5,7 @@
     ../common/base.nix
     ../common/xeon/console.nix
     ../module/emulation.nix
+    ../module/nvidia.nix
   ];
 
   # Select the this using the ID to avoid mismatches
@@ -53,12 +54,8 @@
     extra-trusted-public-keys = [ "jungle.bsc.es:pEc7MlAT0HEwLQYPtpkPLwRsGf80ZI26aj29zMw/HH0=" ];
   };
 
-  # Configure Nvidia driver to use with CUDA
-  hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.production;
+  # Recommended for new graphics cards
   hardware.nvidia.open = true;
-  hardware.graphics.enable = true;
-  nixpkgs.config.nvidia.acceptLicense = true;
-  services.xserver.videoDrivers = [ "nvidia" ];
 
   # Mount NVME disks
   fileSystems."/nvme0" = { device = "/dev/disk/by-label/nvme0"; fsType = "ext4"; };

m/module/nvidia.nix

@@ -0,0 +1,14 @@
+{ lib, config, ... }:
+{
+  # Configure Nvidia driver to use with CUDA
+  hardware.nvidia.package = lib.mkDefault config.boot.kernelPackages.nvidiaPackages.production;
+  hardware.nvidia.open = lib.mkDefault (builtins.abort "hardware.nvidia.open not set");
+  hardware.graphics.enable = true;
+  nixpkgs.config.nvidia.acceptLicense = true;
+  services.xserver.videoDrivers = [ "nvidia" ];
+
+  # enable support for derivations which require nvidia-gpu to be available
+  # > requiredSystemFeatures = [ "cuda" ];
+  programs.nix-required-mounts.enable = true;
+  programs.nix-required-mounts.presets.nvidia-gpu.enable = true;
+}

m/raccoon/configuration.nix

@@ -6,6 +6,7 @@
     ../module/emulation.nix
     ../module/debuginfod.nix
     ../module/ssh-hut-extern.nix
+    ../module/nvidia.nix
     ../eudy/kernel/perf.nix
   ];
 
@@ -49,11 +50,8 @@
   # Enable performance governor
   powerManagement.cpuFreqGovernor = "performance";
 
-  # Configure Nvidia driver to use with CUDA
-  hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.production;
-  hardware.graphics.enable = true;
-  nixpkgs.config.nvidia.acceptLicense = true;
-  services.xserver.videoDrivers = [ "nvidia" ];
+  # Older graphics card, open driver not supported
+  hardware.nvidia.open = false;
 
   # Disable garbage collection for now
   nix.gc.automatic = lib.mkForce false;