PCI: Create alloc_pci_dev(), the one true way to create a struct pci_dev

There are currently several places in the kernel where we kmalloc()
a struct pci_dev and start initialising it. It'd be preferable to
have an allocator so we can ensure the pci_dev is correctly initialised
in one place.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/pci/probe.c

@@ -846,6 +846,21 @@ static void pci_release_bus_bridge_dev(struct device *dev)
 	kfree(dev);
 }
 
+struct pci_dev *alloc_pci_dev(void)
+{
+	struct pci_dev *dev;
+
+	dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL);
+	if (!dev)
+		return NULL;
+
+	INIT_LIST_HEAD(&dev->global_list);
+	INIT_LIST_HEAD(&dev->bus_list);
+
+	return dev;
+}
+EXPORT_SYMBOL(alloc_pci_dev);
+
 /*
  * Read the config data for a PCI device, sanity-check it
  * and fill in the dev structure...

include/linux/pci.h

@@ -193,6 +193,8 @@ struct pci_dev {
 #endif
 };
 
+extern struct pci_dev *alloc_pci_dev(void);
+
 #define pci_dev_g(n) list_entry(n, struct pci_dev, global_list)
 #define pci_dev_b(n) list_entry(n, struct pci_dev, bus_list)
 #define	to_pci_dev(n) container_of(n, struct pci_dev, dev)