VOID
IoStartNextPacketByKey(
IN PDEVICE_OBJECT DeviceObject,
IN BOOLEAN Cancelable,
IN ULONG Key
);
IoStartNextPacketByKey dequeues the next packet from the given device object’s associated device queue according to a specified sort-key value and calls the driver’s StartIo routine with that IRP.
If there are no IRPs currently in the device queue for the target device object, this routine simply returns control to the caller.
Drivers that do not have a StartIo routine cannot call IoStartNextPacketByKey.
Callers of IoStartNextPacketByKey must be running at IRQL <= DISPATCH_LEVEL. Usually, this routine is called from a device driver’s DpcForIsr or CustomDpc routine, both of which are run at IRQL DISPATCH_LEVEL.