Receiving I/O Requests
If a framework-based driver is using the sequential or parallel dispatching method for an I/O queue, it receives I/O requests from the queue as input arguments to its request handlers.
If a framework-based driver is using the manual dispatching method for an I/O queue, it obtains I/O requests from the queue by polling the queue.
After the driver receives a request, it owns the request until it requeues, completes, cancels, or forwards the request.