VOID
IoFreeMapRegisters(
IN PADAPTER_OBJECT AdapterObject,
IN PVOID MapRegisterBase,
IN ULONG NumberOfMapRegisters
);
IoFreeMapRegisters releases a set of map registers that were saved from a call to IoAllocateAdapterChannel when the driver of a busmaster device has completed the current packet-based DMA transfer request.
IoFreeMapRegisters releases map registers previously allocated by a call to IoAllocateAdapterChannel and retained by a busmaster device driver’s AdapterControl routine.
Callers of IoFreeMapRegisters must be running at IRQL DISPATCH_LEVEL.
HalAllocateCommonBuffer, HalGetAdapter, IoAllocateAdapterChannel, IoMapTransfer