hw/pci: add pci_init_nic_devices(), pci_init_nic_in_slot()

The loop over nd_table[] to add PCI NICs is repeated in quite a few
places. Add a helper function to do it.

Some platforms also try to instantiate a specific model in a specific
slot, to match the real hardware. Add pci_init_nic_in_slot() for that
purpose.

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

hw/pci/pci.c

@@ -1925,6 +1925,51 @@ PCIDevice *pci_nic_init_nofail(NICInfo *nd, PCIBus *rootbus,
     return pci_dev;
 }
 
+void pci_init_nic_devices(PCIBus *bus, const char *default_model)
+{
+    qemu_create_nic_bus_devices(&bus->qbus, TYPE_PCI_DEVICE, default_model,
+                                "virtio", "virtio-net-pci");
+}
+
+bool pci_init_nic_in_slot(PCIBus *rootbus, const char *model,
+                          const char *alias, const char *devaddr)
+{
+    NICInfo *nd = qemu_find_nic_info(model, true, alias);
+    int dom, busnr, devfn;
+    PCIDevice *pci_dev;
+    unsigned slot;
+    PCIBus *bus;
+
+    if (!nd) {
+        return false;
+    }
+
+    if (!devaddr || pci_parse_devaddr(devaddr, &dom, &busnr, &slot, NULL) < 0) {
+        error_report("Invalid PCI device address %s for device %s",
+                     devaddr, model);
+        exit(1);
+    }
+
+    if (dom != 0) {
+        error_report("No support for non-zero PCI domains");
+        exit(1);
+    }
+
+    devfn = PCI_DEVFN(slot, 0);
+
+    bus = pci_find_bus_nr(rootbus, busnr);
+    if (!bus) {
+        error_report("Invalid PCI device address %s for device %s",
+                     devaddr, model);
+        exit(1);
+    }
+
+    pci_dev = pci_new(devfn, model);
+    qdev_set_nic_properties(&pci_dev->qdev, nd);
+    pci_realize_and_unref(pci_dev, bus, &error_fatal);
+    return true;
+}
+
 PCIDevice *pci_vga_init(PCIBus *bus)
 {
     vga_interface_created = true;

include/hw/pci/pci.h

@@ -317,7 +317,9 @@ void pci_device_reset(PCIDevice *dev);
 PCIDevice *pci_nic_init_nofail(NICInfo *nd, PCIBus *rootbus,
                                const char *default_model,
                                const char *default_devaddr);
-
+void pci_init_nic_devices(PCIBus *bus, const char *default_model);
+bool pci_init_nic_in_slot(PCIBus *rootbus, const char *default_model,
+                          const char *alias, const char *devaddr);
 PCIDevice *pci_vga_init(PCIBus *bus);
 
 static inline PCIBus *pci_get_bus(const PCIDevice *dev)