bus = kmalloc (sizeof *bus, GFP_KERNEL);
bus = kzalloc (sizeof *bus, GFP_KERNEL);
struct usb_bus *usb_alloc_bus (struct usb_operations *op){	struct usb_bus *bus;	bus = kmalloc (sizeof *bus, GFP_KERNEL);	if (!bus)		return NULL;	memset(bus, 0, sizeof(struct usb_bus));	usb_bus_init (bus);	bus->op = op;	return bus;}