nixpkgs/nixos/modules/virtualisation/kvmgt.nix
2019-09-02 23:25:24 +02:00

83 lines
2.6 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.virtualisation.kvmgt;
kernelPackages = config.boot.kernelPackages;
vgpuOptions = {
uuid = mkOption {
type = types.str;
description = "UUID of VGPU device. You can generate one with <package>libossp_uuid</package>.";
};
};
in {
options = {
virtualisation.kvmgt = {
enable = mkEnableOption ''
KVMGT (iGVT-g) VGPU support. Allows Qemu/KVM guests to share host's Intel integrated graphics card.
Currently only one graphical device can be shared
'';
# multi GPU support is under the question
device = mkOption {
type = types.str;
default = "0000:00:02.0";
description = "PCI ID of graphics card. You can figure it with <command>ls /sys/class/mdev_bus</command>.";
};
vgpus = mkOption {
default = {};
type = with types; attrsOf (submodule [ { options = vgpuOptions; } ]);
description = ''
Virtual GPUs to be used in Qemu. You can find devices via <command>ls /sys/bus/pci/devices/*/mdev_supported_types</command>
and find info about device via <command>cat /sys/bus/pci/devices/*/mdev_supported_types/i915-GVTg_V5_4/description</command>
'';
example = {
i915-GVTg_V5_8 = {
uuid = "a297db4a-f4c2-11e6-90f6-d3b88d6c9525";
};
};
};
};
};
config = mkIf cfg.enable {
assertions = singleton {
assertion = versionAtLeast kernelPackages.kernel.version "4.16";
message = "KVMGT is not properly supported for kernels older than 4.16";
};
boot.kernelModules = [ "kvmgt" ];
boot.extraModprobeConfig = ''
options i915 enable_gvt=1
'';
systemd.paths = mapAttrs' (name: value:
nameValuePair "kvmgt-${name}" {
description = "KVMGT VGPU ${name} path";
wantedBy = [ "multi-user.target" ];
pathConfig = {
PathExists = "/sys/bus/pci/devices/${cfg.device}/mdev_supported_types/${name}/create";
};
}
) cfg.vgpus;
systemd.services = mapAttrs' (name: value:
nameValuePair "kvmgt-${name}" {
description = "KVMGT VGPU ${name}";
serviceConfig = {
Type = "oneshot";
RemainAfterExit = true;
ExecStart = "${pkgs.runtimeShell} -c 'echo ${value.uuid} > /sys/bus/pci/devices/${cfg.device}/mdev_supported_types/${name}/create'";
ExecStop = "${pkgs.runtimeShell} -c 'echo 1 > /sys/bus/pci/devices/${cfg.device}/${value.uuid}/remove'";
};
}
) cfg.vgpus;
};
meta.maintainers = with maintainers; [ gnidorah ];
}