nixpkgs/nixos/lib/qemu-common.nix
Max Hausch a2465483e8
nixos/lib/qemu-common: Opportunistically use KVM
This will try to use KVM if available and fallback to using TCG if not.
Useful for nested virtualisation of arm on x86.
2022-04-05 11:49:42 +02:00

33 lines
1.4 KiB
Nix

# QEMU-related utilities shared between various Nix expressions.
{ lib, pkgs }:
let
zeroPad = n:
lib.optionalString (n < 16) "0" +
(if n > 255
then throw "Can't have more than 255 nets or nodes!"
else lib.toHexString n);
in
rec {
qemuNicMac = net: machine: "52:54:00:12:${zeroPad net}:${zeroPad machine}";
qemuNICFlags = nic: net: machine:
[ "-device virtio-net-pci,netdev=vlan${toString nic},mac=${qemuNicMac net machine}"
''-netdev vde,id=vlan${toString nic},sock="$QEMU_VDE_SOCKET_${toString net}"''
];
qemuSerialDevice = if pkgs.stdenv.hostPlatform.isx86 || pkgs.stdenv.hostPlatform.isRiscV then "ttyS0"
else if (with pkgs.stdenv.hostPlatform; isAarch32 || isAarch64 || isPower) then "ttyAMA0"
else throw "Unknown QEMU serial device for system '${pkgs.stdenv.hostPlatform.system}'";
qemuBinary = qemuPkg: {
x86_64-linux = "${qemuPkg}/bin/qemu-kvm -cpu max";
armv7l-linux = "${qemuPkg}/bin/qemu-system-arm -machine virt,accel=kvm:tcg -cpu max";
aarch64-linux = "${qemuPkg}/bin/qemu-system-aarch64 -machine virt,gic-version=max,accel=kvm:tcg -cpu max";
powerpc64le-linux = "${qemuPkg}/bin/qemu-system-ppc64 -machine powernv";
powerpc64-linux = "${qemuPkg}/bin/qemu-system-ppc64 -machine powernv";
x86_64-darwin = "${qemuPkg}/bin/qemu-kvm -cpu max";
}.${pkgs.stdenv.hostPlatform.system} or "${qemuPkg}/bin/qemu-kvm";
}