From a4e0278fcd8c6bd98b4e003fa273c4cd63d7b383 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <eelco.dolstra@logicblox.com>
Date: Tue, 3 Mar 2015 20:15:38 +0100
Subject: [PATCH] Create /dev/nvidia-uvm for CUDA support

---
 nixos/modules/hardware/video/nvidia.nix | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/nixos/modules/hardware/video/nvidia.nix b/nixos/modules/hardware/video/nvidia.nix
index 2b20dc7395a..209310bec99 100644
--- a/nixos/modules/hardware/video/nvidia.nix
+++ b/nixos/modules/hardware/video/nvidia.nix
@@ -47,6 +47,15 @@ in
 
     boot.extraModulePackages = [ nvidia_x11 ];
 
+    # nvidia-uvm is required by CUDA applications.
+    boot.kernelModules = [ "nvidia-uvm" ];
+
+    # Create /dev/nvidia-uvm when the nvidia-uvm module is loaded.
+    services.udev.extraRules =
+      ''
+        KERNEL=="nvidia_uvm", RUN+="${pkgs.stdenv.shell} -c 'mknod -m 666 /dev/nvidia-uvm c $(grep nvidia-uvm /proc/devices | cut -d \  -f 1) 0'"
+      '';
+
     boot.blacklistedKernelModules = [ "nouveau" "nvidiafb" ];
 
     services.acpid.enable = true;