diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
index b70a0b95ff..ea5aff118b 100644
--- a/include/hw/pci/pci.h
+++ b/include/hw/pci/pci.h
@@ -279,12 +279,10 @@ bool pci_bus_is_express(const PCIBus *bus);
 
 void pci_root_bus_init(PCIBus *bus, size_t bus_size, DeviceState *parent,
                        const char *name,
-                       MemoryRegion *address_space_mem,
-                       MemoryRegion *address_space_io,
+                       MemoryRegion *mem, MemoryRegion *io,
                        uint8_t devfn_min, const char *typename);
 PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
-                         MemoryRegion *address_space_mem,
-                         MemoryRegion *address_space_io,
+                         MemoryRegion *mem, MemoryRegion *io,
                          uint8_t devfn_min, const char *typename);
 void pci_root_bus_cleanup(PCIBus *bus);
 void pci_bus_irqs(PCIBus *bus, pci_set_irq_fn set_irq,
@@ -304,8 +302,7 @@ int pci_swizzle_map_irq_fn(PCIDevice *pci_dev, int pin);
 PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
                               pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
                               void *irq_opaque,
-                              MemoryRegion *address_space_mem,
-                              MemoryRegion *address_space_io,
+                              MemoryRegion *mem, MemoryRegion *io,
                               uint8_t devfn_min, int nirq,
                               const char *typename);
 void pci_unregister_root_bus(PCIBus *bus);
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index b0d21bf43a..7d09e1a39d 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -500,15 +500,14 @@ bool pci_bus_bypass_iommu(PCIBus *bus)
 }
 
 static void pci_root_bus_internal_init(PCIBus *bus, DeviceState *parent,
-                                       MemoryRegion *address_space_mem,
-                                       MemoryRegion *address_space_io,
+                                       MemoryRegion *mem, MemoryRegion *io,
                                        uint8_t devfn_min)
 {
     assert(PCI_FUNC(devfn_min) == 0);
     bus->devfn_min = devfn_min;
     bus->slot_reserved_mask = 0x0;
-    bus->address_space_mem = address_space_mem;
-    bus->address_space_io = address_space_io;
+    bus->address_space_mem = mem;
+    bus->address_space_io = io;
     bus->flags |= PCI_BUS_IS_ROOT;
 
     /* host bridge */
@@ -529,25 +528,21 @@ bool pci_bus_is_express(const PCIBus *bus)
 
 void pci_root_bus_init(PCIBus *bus, size_t bus_size, DeviceState *parent,
                        const char *name,
-                       MemoryRegion *address_space_mem,
-                       MemoryRegion *address_space_io,
+                       MemoryRegion *mem, MemoryRegion *io,
                        uint8_t devfn_min, const char *typename)
 {
     qbus_init(bus, bus_size, typename, parent, name);
-    pci_root_bus_internal_init(bus, parent, address_space_mem,
-                               address_space_io, devfn_min);
+    pci_root_bus_internal_init(bus, parent, mem, io, devfn_min);
 }
 
 PCIBus *pci_root_bus_new(DeviceState *parent, const char *name,
-                         MemoryRegion *address_space_mem,
-                         MemoryRegion *address_space_io,
+                         MemoryRegion *mem, MemoryRegion *io,
                          uint8_t devfn_min, const char *typename)
 {
     PCIBus *bus;
 
     bus = PCI_BUS(qbus_new(typename, parent, name));
-    pci_root_bus_internal_init(bus, parent, address_space_mem,
-                               address_space_io, devfn_min);
+    pci_root_bus_internal_init(bus, parent, mem, io, devfn_min);
     return bus;
 }
 
@@ -586,15 +581,13 @@ void pci_bus_irqs_cleanup(PCIBus *bus)
 PCIBus *pci_register_root_bus(DeviceState *parent, const char *name,
                               pci_set_irq_fn set_irq, pci_map_irq_fn map_irq,
                               void *irq_opaque,
-                              MemoryRegion *address_space_mem,
-                              MemoryRegion *address_space_io,
+                              MemoryRegion *mem, MemoryRegion *io,
                               uint8_t devfn_min, int nirq,
                               const char *typename)
 {
     PCIBus *bus;
 
-    bus = pci_root_bus_new(parent, name, address_space_mem,
-                           address_space_io, devfn_min, typename);
+    bus = pci_root_bus_new(parent, name, mem, io, devfn_min, typename);
     pci_bus_irqs(bus, set_irq, irq_opaque, nirq);
     pci_bus_map_irqs(bus, map_irq);
     return bus;
