nixos/lib/qemu-common.nix

   1 # QEMU-related utilities shared between various Nix expressions.
   2 { lib, pkgs }:
   3
   4 let
   5   zeroPad = n:
   6     lib.optionalString (n < 16) "0" +
   7     (if n > 255
   8     then throw "Can't have more than 255 nets or nodes!"
   9     else lib.toHexString n);
  10 in
  11
  12 rec {
  13   qemuNicMac = net: machine: "52:54:00:12:${zeroPad net}:${zeroPad machine}";
  14
  15   qemuNICFlags = nic: net: machine:
  16     [
  17       "-device virtio-net-pci,netdev=vlan${toString nic},mac=${qemuNicMac net machine}"
  18       ''-netdev vde,id=vlan${toString nic},sock="$QEMU_VDE_SOCKET_${toString net}"''
  19     ];
  20
  21   qemuSerialDevice =
  22     if with pkgs.stdenv.hostPlatform; isx86 || isLoongArch64 || isMips64 || isRiscV then "ttyS0"
  23     else if (with pkgs.stdenv.hostPlatform; isAarch || isPower) then "ttyAMA0"
  24     else throw "Unknown QEMU serial device for system '${pkgs.stdenv.hostPlatform.system}'";
  25
  26   qemuBinary = qemuPkg:
  27     let
  28       hostStdenv = qemuPkg.stdenv;
  29       hostSystem = hostStdenv.system;
  30       guestSystem = pkgs.stdenv.hostPlatform.system;
  31
  32       linuxHostGuestMatrix = {
  33         x86_64-linux = "${qemuPkg}/bin/qemu-kvm -cpu max";
  34         armv7l-linux = "${qemuPkg}/bin/qemu-system-arm -machine virt,accel=kvm:tcg -cpu max";
  35         aarch64-linux = "${qemuPkg}/bin/qemu-system-aarch64 -machine virt,gic-version=max,accel=kvm:tcg -cpu max";
  36         powerpc64le-linux = "${qemuPkg}/bin/qemu-system-ppc64 -machine powernv";
  37         powerpc64-linux = "${qemuPkg}/bin/qemu-system-ppc64 -machine powernv";
  38         x86_64-darwin = "${qemuPkg}/bin/qemu-kvm -cpu max";
  39       };
  40       otherHostGuestMatrix = {
  41         aarch64-darwin = {
  42           aarch64-linux = "${qemuPkg}/bin/qemu-system-aarch64 -machine virt,gic-version=2,accel=hvf:tcg -cpu max";
  43           inherit (otherHostGuestMatrix.x86_64-darwin) x86_64-linux;
  44         };
  45         x86_64-darwin = {
  46           x86_64-linux = "${qemuPkg}/bin/qemu-system-x86_64 -machine type=q35,accel=hvf:tcg -cpu max";
  47         };
  48       };
  49
  50       throwUnsupportedHostSystem =
  51         let
  52           supportedSystems = [ "linux" ] ++ (lib.attrNames otherHostGuestMatrix);
  53         in
  54         throw "Unsupported host system ${hostSystem}, supported: ${lib.concatStringsSep ", " supportedSystems}";
  55       throwUnsupportedGuestSystem = guestMap:
  56         throw "Unsupported guest system ${guestSystem} for host ${hostSystem}, supported: ${lib.concatStringsSep ", " (lib.attrNames guestMap)}";
  57     in
  58     if hostStdenv.isLinux then
  59       linuxHostGuestMatrix.${guestSystem} or "${qemuPkg}/bin/qemu-kvm"
  60     else
  61       let
  62         guestMap = (otherHostGuestMatrix.${hostSystem} or throwUnsupportedHostSystem);
  63       in
  64       (guestMap.${guestSystem} or (throwUnsupportedGuestSystem guestMap));
  65 }