VOID
IoFreeController(
IN PCONTROLLER_OBJECT ControllerObject
);
IoFreeController releases a previously allocated controller object when the driver has completed an I/O request.
The connection between the current target device object and the controller object is released only if no requests are currently queued to the same device. Otherwise, the driver’s ControllerControl routine is called with the next IRP bound through the device controller to the target device.
Callers of IoFreeController must be running at IRQL DISPATCH_LEVEL.
IoAllocateController, IoCreateController, IoDeleteController