1 files changed, 148 insertions, 0 deletions
diff --git a/nixos/modules/virtualisation/libvirtd.nix b/nixos/modules/virtualisation/libvirtd.nix
new file mode 100644
index 00000000000..52dab153094
--- /dev/null
+++ b/nixos/modules/virtualisation/libvirtd.nix
@@ -0,0 +1,148 @@
+# Upstart jobs for libvirtd.
+
+{ config, pkgs, ... }:
+
+with pkgs.lib;
+
+let
+
+  cfg = config.virtualisation.libvirtd;
+  configFile = pkgs.writeText "libvirtd.conf" ''
+    unix_sock_group = "libvirtd"
+    unix_sock_rw_perms = "0770"
+    auth_unix_ro = "none"
+    auth_unix_rw = "none"
+    ${cfg.extraConfig}
+  '';
+
+in
+
+{
+  ###### interface
+
+  options = {
+
+    virtualisation.libvirtd.enable =
+      mkOption {
+        default = false;
+        description =
+          ''
+            This option enables libvirtd, a daemon that manages
+            virtual machines. Users in the "libvirtd" group can interact with
+            the daemon (e.g. to start or stop VMs) using the
+            <command>virsh</command> command line tool, among others.
+          '';
+      };
+
+    virtualisation.libvirtd.enableKVM =
+      mkOption {
+        default = true;
+        description =
+          ''
+            This option enables support for QEMU/KVM in libvirtd.
+          '';
+      };
+
+    virtualisation.libvirtd.extraConfig =
+      mkOption {
+        default = "";
+        description =
+          ''
+            Extra contents appended to the libvirtd configuration file,
+            libvirtd.conf.
+          '';
+      };
+
+  };
+
+
+  ###### implementation
+
+  config = mkIf cfg.enable {
+
+    environment.systemPackages =
+      [ pkgs.libvirt ]
+       ++ optional cfg.enableKVM pkgs.qemu_kvm;
+
+    boot.kernelModules = [ "tun" ];
+
+    systemd.services.libvirtd =
+      { description = "Libvirt Virtual Machine Management Daemon";
+
+        wantedBy = [ "multi-user.target" ];
+        after = [ "systemd-udev-settle.service" ];
+
+        path =
+          [ pkgs.bridge_utils pkgs.dmidecode pkgs.dnsmasq
+            pkgs.ebtables
+          ] ++ optional cfg.enableKVM pkgs.qemu_kvm;
+
+        preStart =
+          ''
+            mkdir -p /var/log/libvirt/qemu -m 755
+            rm -f /var/run/libvirtd.pid
+
+            mkdir -p /var/lib/libvirt -m 700
+            mkdir -p /var/lib/libvirt/dnsmasq -m 700
+
+            # Libvirt unfortunately writes mutable state (such as
+            # runtime changes to VM, network or filter configurations)
+            # to /etc.  So we can't use environment.etc to make the
+            # default network and filter definitions available, since
+            # libvirt will then modify the originals in the Nix store.
+            # So here we copy them instead.  Ugly.
+            for i in $(cd ${pkgs.libvirt}/etc && echo \
+                libvirt/qemu/networks/*.xml libvirt/qemu/networks/autostart/*.xml \
+                libvirt/nwfilter/*.xml );
+            do
+                mkdir -p /etc/$(dirname $i) -m 755
+                cp -fpd ${pkgs.libvirt}/etc/$i /etc/$i
+            done
+          ''; # */
+
+        serviceConfig.ExecStart = ''@${pkgs.libvirt}/sbin/libvirtd libvirtd --config "${configFile}" --daemon --verbose'';
+        serviceConfig.Type = "forking";
+        serviceConfig.KillMode = "process"; # when stopping, leave the VMs alone
+
+        # Wait until libvirtd is ready to accept requests.
+        postStart =
+          ''
+            for ((i = 0; i < 60; i++)); do
+                if ${pkgs.libvirt}/bin/virsh list > /dev/null; then exit 0; fi
+                sleep 1
+            done
+            exit 1 # !!! seems to be ignored
+          '';
+      };
+
+    jobs."libvirt-guests" =
+      { description = "Libvirt Virtual Machines";
+
+        wantedBy = [ "multi-user.target" ];
+        wants = [ "libvirtd.service" ];
+        after = [ "libvirtd.service" ];
+
+        # We want to suspend VMs only on shutdown, but Upstart is broken.
+        #stopOn = "";
+
+        restartIfChanged = false;
+
+        path = [ pkgs.gettext pkgs.libvirt pkgs.gawk ];
+
+        preStart =
+          ''
+            mkdir -p /var/lock/subsys -m 755
+            ${pkgs.libvirt}/etc/rc.d/init.d/libvirt-guests start || true
+          '';
+
+        postStop = "${pkgs.libvirt}/etc/rc.d/init.d/libvirt-guests stop";
+
+        serviceConfig.Type = "oneshot";
+        serviceConfig.RemainAfterExit = true;
+      };
+
+    users.extraGroups.libvirtd.gid = config.ids.gids.libvirtd;
+
+  };
+
+}