NdisImmediateReadSharedMemory

NdisImmediateReadSharedMemory

VOID
   NdisImmediateReadSharedMemory(
       IN NDIS_HANDLE WrapperConfigurationContext,
       IN ULONG SharedMemoryAddress,
       OUT PUCHAR Buffer,
       IN ULONG Length
       );

NdisImmediateReadSharedMemory reads a specified number of bytes from shared device RAM.

Parameters

WrapperConfigurationContext

Specifies the handle passed to MiniportInitialize.

SharedMemoryAddress

Specifies the bus-relative base address of the shared device memory range.

Buffer

Points to a caller-allocated buffer in which this function returns the data read from the device memory range starting at SharedMemoryAddress.

Length

Specifies the size in bytes of the buffer at Buffer and, therefore, how many bytes of data to return.

Comments

NdisImmediateReadShared Memory determines how the host accesses shared device memory, maps the bus-relative base address, and then copies Length bytes of data from the device memory area into the given buffer.

A miniport driver can call NdisImmediateReadSharedMemory during initialization to read data from a range of device memory when that driver has not yet called NdisMMapIoSpace to obtain mapped virtual addresses for the bus-relative device memory range. After its call to NdisMMapIoSpace, the driver uses the returned mapped virtual addresses in PIO operations.

Callers of NdisImmediateReadSharedMemory run at IRQL PASSIVE_LEVEL.