hw/i386/pc: support '-nic' for xen-net-device

The default NIC creation seems a bit hackish to me. I don't understand
why each platform has to call pci_nic_init_nofail() from a point in the
code where it actually has a pointer to the PCI bus, and then we have
the special cases for things like ne2k_isa.

If qmp_device_add() can *find* the appropriate bus and instantiate
the device on it, why can't we just do that from generic code for
creating the default NICs too?

But that isn't a yak I want to shave today. Add a xenbus field to the
PCMachineState so that it can make its way from pc_basic_device_init()
to pc_nic_init() and be handled as a special case like ne2k_isa is.

Now we can launch emulated Xen guests with '-nic user'.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Paul Durrant <paul@xen.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/hw/xen/xen-bus.c b/hw/xen/xen-bus.c
index cc6f1b362f..4973e7d9c9 100644
--- a/hw/xen/xen-bus.c
+++ b/hw/xen/xen-bus.c
@@ -1133,11 +1133,13 @@ static void xen_register_types(void)
 
 type_init(xen_register_types)
 
-void xen_bus_init(void)
+BusState *xen_bus_init(void)
 {
     DeviceState *dev = qdev_new(TYPE_XEN_BRIDGE);
     BusState *bus = qbus_new(TYPE_XEN_BUS, dev, NULL);
 
     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
     qbus_set_bus_hotplug_handler(bus);
+
+    return bus;
 }