NET_ADAPTER_TX_CAPABILITIES structure (netadapter.h)

The NET_ADAPTER_TX_CAPABILITIES structure describes the transmit capabilities of a net adapter.

Syntax

typedef struct _NET_ADAPTER_TX_CAPABILITIES {
  ULONG                          Size;
  NET_MEMORY_MAPPING_REQUIREMENT MappingRequirement;
  SIZE_T                         PayloadBackfill;
  SIZE_T                         MaximumNumberOfFragments;
  SIZE_T                         FragmentBufferAlignment;
  UINT32                         FragmentRingNumberOfElementsHint;
  SIZE_T                         MaximumNumberOfQueues;
  NET_ADAPTER_DMA_CAPABILITIES   *DmaCapabilities;
} NET_ADAPTER_TX_CAPABILITIES;

Members

Size

The size of this structure, in bytes.

MappingRequirement

A NET_MEMORY_MAPPING_REQUIREMENT value that specifies how the operating system should map transmit data buffers.

UMDF drivers must set MappingRequirement to NetMemoryMappingRequirementNone.

PayloadBackfill

The amount of space, in bytes, reserved for the client driver before the start of each NET_PACKET's payload.

MaximumNumberOfFragments

The maximum number of fragments per packet that the adapter can handle, or ((SIZE_T) - 1) if there is no limit.

FragmentBufferAlignment

The minimum alignment for packet fragments. This member must be a power of 2.

FragmentRingNumberOfElementsHint

A hint indicating how many elements the adapter wants for each transmit queue's NET_FRAGMENT ring buffer. This member must be a power of 2.

MaximumNumberOfQueues

The maximum number of transmit queues that the adapter supports.

DmaCapabilities

A pointer to a driver-allocated and initialized NET_DMA_CAPABILITIES structure that describes the adapter's DMA capabilities on the transmit path. This member is ignored by NetAdapterCx if MappingRequirement is not set to NetMemoryMappingRequirementDmaMapped.

UMDF NetAdapterCX doesn't support DmaCapabilities. UMDF drivers must set this member to NULL.

Remarks

Call one of the NET_ADAPTER_TX_CAPABILITIES_INIT_XXX functions to initialize this structure. For more info about each initialization function, see the links in the See Also section.

An initialized NET_ADAPTER_TX_CAPABILITIES structure is passed as a parameter to NetAdapterSetDatapathCapabilities.

Requirements

Requirement Value
Minimum KMDF version 1.27
Minimum UMDF version 2.33
Header netadapter.h (include netadaptercx.h)

See also

NET_ADAPTER_TX_CAPABILITIES_INIT

NET_ADAPTER_TX_CAPABILITIES_INIT_FOR_DMA