NdisMMapIoSpace

NdisMMapIoSpace

NDIS_STATUS
   NdisMMapIoSpace(
       OUT PVOID *VirtualAddress,
       IN NDIS_HANDLE MiniportAdapterHandle,
       IN NDIS_PHYSICAL_ADDRESS PhysicalAddress,
       IN UINT Length
       );

NdisMMapIoSpace maps a given bus-relative “physical” range of device RAM or registers onto a system-space virtual range.

Parameters

Virtual Address

Points to a caller-supplied variable that is set to the converted virtual address if the call is successful.

MiniportAdapterHandle

Specifies the handle input to MiniportInitialize.

PhysicalAddress

Specifies the bus-relative base physical address of the device memory range to be mapped.

Length

Specifies the number of bytes to be mapped.

Return Value

NdisMMapIoSpace can return any of the following status values:

NDIS_STATUS_SUCCESS

The device memory range was mapped successfully so the value at VirtualAddress is valid and the mapped range has been claimed in the registry for the NIC.

NDIS_STATUS_RESOURCE_CONFLICT

An attempt to claim the device memory range in the registry has failed, possibly because another driver has already claimed the range for its device. NdisMMapIoSpace logs an error if this occurs.

NDIS_STATUS_RESOURCES

The memory could not be mapped or sufficient virtual memory could not be allocated.

NDIS_STATUS_FAILURE

Either the bus type or bus number is out of range or the given PhysicalAddress and Length were invalid (possibly not within the I/O space of the current platform).

Comments

This function is called by drivers of NICs that have on-board memory or a bank of device registers appearing in the I/O space of the host. For example, the driver of a NIC that uses PIO calls NdisMMapIoSpace.

A successful call to NdisMMapIoSpace claims hardware resources in the registry for the driver’s NIC. Consequently, only MiniportInitialize functions call NdisMMapIoSpace.

NdisMMapIoSpace sets the variable at VirtualAddress to NULL if it does not return NDIS_STATUS_SUCCESS.

MiniportInitialize either gets the PhysicalAddress value from the driver’s Parameters registry key or by calling a bus-type-specific NdisXxx configuration function. The given physical address range must fall within the I/O space of the current platform. It is a programming error to call NdisMMapIoSpace with a host physical memory address.

A miniport must call the reciprocal NdisMUnmapIoSpace to release its claim on system resources if MiniportInitialize subsequently fails to initialize the NIC, if its NIC is removed from the machine, and/or when the driver is unloading.

Callers of NdisMMapIoSpace run at IRQL PASSIVE_LEVEL.