NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure

[The TCP chimney offload feature is deprecated and should not be used.]

The NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure is the basic building block of a TCP chimney offload state tree. An offload state tree can contain one or more NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structures.

Syntax


typedef struct _NDIS_MINIPORT_OFFLOAD_BLOCK_LIST {
  NDIS_OBJECT_HEADER                       Header;
  struct _NDIS_MINIPORT_OFFLOAD_BLOCK_LIST  *NextBlock;
  struct _NDIS_MINIPORT_OFFLOAD_BLOCK_LIST  *DependentBlockList;
  NDIS_STATUS                              Status;
  PVOID                                    NdisReserved[2];
  PVOID                                    *MiniportOffloadContext;
  NDIS_HANDLE                              NdisOffloadHandle;
  PVOID                                    ProtocolReserved[2];
  PVOID                                    MiniportReserved[2];
  PVOID                                    ImReserved[2];
  PVOID                                    Scratch[2];
  PVOID                                    SourceHandle;
  NDIS_PORT_NUMBER                         PortNumber;
  PNET_BUFFER_LIST                         NetBufferListChain;
} NDIS_MINIPORT_OFFLOAD_BLOCK_LIST, *PNDIS_MINIPORT_OFFLOAD_BLOCK_LIST;

Members

Header

The header of the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure. The header is formatted as an NDIS_OBJECT_HEADER structure. The NDIS_OBJECT_HEADER structure contains the revision number of the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure, the type of offload state that immediately follows the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure in memory, and the size of the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure, including the header, in bytes.

The Type member of the NDIS_OBJECT_HEADER structure indicates the type of offload state, and by implication, the specific offload state structure (or structures) that immediately follow the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure in memory.

The following OFFLOAD_STATE_TYPE values are supported:

NeighborOffloadConstState

Specifies the constant neighbor state. This state is formatted as a NEIGHBOR_OFFLOAD_STATE_CONST structure.

NeighborOffloadCachedState

Specifies the cached neighbor state. This state is formatted as a NEIGHBOR_OFFLOAD_STATE_CACHED structure.

NeighborOffloadDelegatedState

Specifies the delegated neighbor state. This state is formatted as a NEIGHBOR_OFFLOAD_STATE_DELEGATED structure.

NeighborOffloadState

Specifies all of the neighbor state information, including the constant, cached, and delegated neighbor state. This state is formatted as a NEIGHBOR_OFFLOAD_STATE_CONST structure, followed by a NEIGHBOR_OFFLOAD_STATE_CACHED structure, followed by a NEIGHBOR_OFFLOAD_STATE_DELEGATED structure.

Ip4OffloadConstState

Specifies the constant path state (IPv4). This state is formatted as a PATH_OFFLOAD_STATE_CONST structure.

Ip4OffloadCachedState

Specifies the cached path state (IPv4). This state is formatted as a PATH_OFFLOAD_STATE_CACHED structure.

Ip4OffloadDelegatedState

Specifies the delegated path state (IPv4). This state is formatted as a PATH_OFFLOAD_STATE_DELEGATED structure. Currently there is no delegated path state. The PATH_OFFLOAD_STATE_DELEGATED structure does not contain any variables.

Ip4OffloadState

Specifies all of the path state (IPv4), including the constant, cached, and delegated path state. This state is formatted as a PATH_OFFLOAD_STATE_CONST structure, followed by a PATH_OFFLOAD_STATE_CACHED structure, followed by a PATH_OFFLOAD_STATE_DELEGATED structure.

Ip6OffloadConstState

Specifies the constant path state (IPv6). This state is formatted as a PATH_OFFLOAD_STATE_CONST structure.

Ip6OffloadCachedState

Specifies the cached path state (IPv6). This state is formatted as a PATH_OFFLOAD_STATE_CACHED structure.

Ip6OffloadDelegatedState

Specifies the delegated path state (IPv6). This state is formatted as a PATH_OFFLOAD_STATE_DELEGATED structure. Currently, there is no delegated path state. The PATH_OFFLOAD_STATE_DELEGATED structure does not contain any variables.

Ip6OffloadState

Specifies all of the path state information(IPv6), including the constant, cached, and delegated path state. This state is formatted as a PATH_OFFLOAD_STATE_CONST structure, followed by a PATH_OFFLOAD_STATE_CACHED structure, followed by a PATH_OFFLOAD_STATE_DELEGATED structure.

TcpOffloadConstState

Specifies the constant TCP state. This state is formatted as a TCP_OFFLOAD_STATE_CONST structure.

TcpOffloadCachedState

Specifies the cached TCP state. This state is formatted as a TCP_OFFLOAD_STATE_CACHED structure.

TcpOffloadDelegatedState

Specifies the delegated TCP state. This state is formatted as a TCP_OFFLOAD_STATE_DELEGATED structure.

TcpOffloadResourceState

Reserved. This OFFLOAD_STATE_TYPE value, as well as the TCP_OFFLOAD_RESOURCE_STATE structure, are currently not used.

TcpOffloadState

Specifies all of the TCP state information, including the constant, cached, and delegated TCP state. This state is formatted as a TCP_OFFLOAD_STATE_CONST structure, followed by a TCP_OFFLOAD_STATE_CACHED structure, followed by a TCP_OFFLOAD_STATE_DELEGATED structure.

FilterReservedOffloadState

Reserved for filter drivers.

NextBlock

A pointer to the next NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure at the offload state layer (neighbor, path, or TCP) indicated by the Type member of the Header member. NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structures that are linked through NextBlock pointers are always at the same layer of the offload state. A NextBlock value of NULL indicates that there is no additional next NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure at this level.

DependentBlockList

A pointer to an NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure that is at a dependent layer of the offload state (a higher layer in the offload state tree). For TCP chimney offload:

  • The DependentBlockList member of an NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure at the neighbor layer can point only to an NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure at the path layer.

  • The DependentBlockList member of an NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure at the path layer can point only to an NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure at the TCP layer.

  • The DependentBlockList member of an NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure at the TCP layer is always NULL.

A DependentBlockList value of NULL indicates that there is no dependent NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure.

Status

The completion status of an initiate offload, query offload, update offload, invalidate offload, or terminate offload operation that the offload target performed on the state associated with, or referenced by, the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure. Depending on the operation, the offload target writes one of the following NDIS_STATUS values to the Status member:

NDIS_STATUS_SUCCESS

Initiate offload: The offload target successfully offloaded the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure and the state associated with all of the immediately dependent NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structures.

Query, update, invalidate, or terminate offload: The offload target successfully performed the operation on the state associated with, or referenced by, the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure.

NDIS_STATUS_OFFLOAD_PARTIAL_SUCCESS

Initiate offload: The offload target successfully offloaded the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure, but failed to offload the state associated with one or more of the immediately dependent NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structures.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_FAILURE

Initiate offload: The offload target failed to offload the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure. The cause of the failure cannot be categorized.

Query, update, invalidate, or terminate offload: The offload target failed to perform the operation on the state associated with, or referenced by, the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure.

NDIS_STATUS_RESOURCES

Initiate offload: The offload target failed to offload the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure because the offload target could not allocate sufficient host memory.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_OFFLOAD_TCP_ENTRIES

Initiate offload: The offload target failed to offload the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure because the offload target could not allocate a TCP connection state object.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_OFFLOAD_PATH_ENTRIES

Initiate offload: The offload target failed to offload the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure because the offload target could not allocate a path state object.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_OFFLOAD_NEIGHBOR_ENTRIES

Initiate offload: The offload target failed to offload the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure because the offload target could not allocate a neighbor state object.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_OFFLOAD_HW_ADDRESS_ENTRIES

Initiate offload: The offload target failed to offload the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure because the host stack specified a non-NULLDlSourceAddress member in the NEIGHBOR_OFFLOAD_STATE_CONST structure, and the offload target either does not support configurable source MAC addresses or cannot accept additional source MAC addresses.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_OFFLOAD_IP_ADDRESS_ENTRIES

Initiate offload: The offload target failed to offload the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure because the offload target could not allocate a data structure for the source IP address that is referenced by the SourceAddress pointer in the PATH_OFFLOAD_STATE_CONST structure.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_OFFLOAD_TCP_XMIT_BUFFER

Initiate offload: The offload target failed to offload the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure because the offload target could not allocate enough TCP transmit buffers.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_OFFLOAD_TCP_RCV_BUFFER

Initiate offload: The offload target failed to offload the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure because the offload target could not allocate enough TCP receive buffers.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_OFFLOAD_TCP_RCV_WINDOW

Initiate offload: The offload target failed to offload the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure because the InitialRcvWnd member specified in the TCP_OFFLOAD_STATE_CACHED structure is larger than the offload target can support.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_OFFLOAD_VLAN_ENTRIES

Initiate offload: The offload target has run out of resources for tracking additional VLAN IDs.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_OFFLOAD_VLAN_MISMATCH

Initiate offload: The neighbor VlanId is non-zero and does not match one of the interface VLAN IDs.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NDIS_STATUS_OFFLOAD_PATH_MTU

The path MTU for the TCP connection is larger than the offload target supports.

Query, update, invalidate, or terminate offload: Not an allowed status value.

NdisReserved

Reserved for use by NDIS.

MiniportOffloadContext

A pointer to a memory location into which the offload target writes a PVOID value. The PVOID value references the offload context area in which the offload target stores the state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure. If the state is a new state to be offloaded by the offload target, the memory location pointed to by MiniportOffloadContext contains a NULL value. After offloading the state, the offload target writes a PVOID value to this memory location. The PVOID value supplied by the offload target references the offload context area into which the state was offloaded. If the MiniportOffloadContext member itself is NULL, the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure is a placeholder in the offload state tree.

NdisOffloadHandle

The handle that the offload target supplies in subsequent calls to the NdisTcpOffloadEventHandler function or the NdisTcpOffloadReceiveHandler function when making an indication on the offload state associated with this NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure.

ProtocolReserved

Reserved for use by protocol drivers, which can use this area for their own purposes. Offload targets must not modify this value.

MiniportReserved

Reserved for use by offload targets, which can use this area for their own purposes, such as queuing up the offload state associated with the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure.

ImReserved

Reserved for use by intermediate drivers, which can use this area for their own purposes. Offload targets must not modify this value.

Scratch

The offload target can use this area for internal tracking. The information in this area is valid only while the offload target has ownership of the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST.

SourceHandle

This member is not significant for an offload target. An offload target must not modify this member.

PortNumber

A port number that identifies a miniport adapter port. To assign a miniport adapter port number, call the NdisMAllocatePort function. A zero value identifies the default port of a miniport adapter. Use the default port if the miniport driver has not allocated ports for the specified adapter.

NetBufferListChain

When the host stack specifies a NULL value, NetBufferListChain is not significant and can be ignored by the offload target.

When the host stack specifies a non-NULL value, NetBufferListChain points to a NET_BUFFER_LIST structure that can be a stand-alone structure or the first structure in a linked list of such structures. Each NET_BUFFER_LIST structure in the linked list describes one NET_BUFFER structure. The NET_BUFFER structure maps to a chain of memory descriptor lists (MDLs). The NET_BUFFER_LIST and associated structures are locked so that they remain resident in physical memory. However, they are not mapped into system memory.

The MDLs associated with the NET_BUFFER structures contain data that the host stack is passing to the offload target as part of the offload operation. The offload target completes such data asynchronously back to the host stack by calling the appropriate NdisTcpOffloadXxxComplete function. At present, the linked list can contain just one type of data: outstanding send data. For more information, see Handling Outstanding Send Data During and After an Offload Operation.

An offload target can pass outstanding send data to the host stack when terminating the offload of a TCP connection. In this case, the offload target specifies a non-NULL value for the NetBufferListChain member when calling the NdisMTerminateOffloadComplete function. If the offload target is not passing send data for a TCP connection that is being terminated, it must specify a NULL value for the NetBufferListChain member.

Remarks

NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structures can be linked together to build the framework of a TCP chimney offload state tree.

Through NDIS, the host stack passes an OffloadBlockList pointer, which references an offload state tree to one of the following functions of an offload target:

The offload target returns the tree to the host stack by passing the same pointer to the corresponding completion function:

An NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure can be immediately followed in memory by an offload state structure that contains state to be offloaded, queried, updated, invalidated, or terminated. The Type member of the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure's Header specifies the type of offload state, and by implication, the specific offload state structure (or structures) that follow the NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure in memory.

The host stack and offload target use the *MiniportOffloadContext and NdisOffloadHandle members of an NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure to reference offloaded state. For more information, see Storing and Referencing Offloaded State.

An NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure can perform one of several functions in an offload state tree. It can function as a placeholder, a linker, or it can convey new state to be offloaded by the offload target. For more information, see Placeholders, Linkers, and New Offloads.

Before completing an initiate offload, query offload, update offload, invalidate offload, or terminate offload operation, an offload target must write the completion status to the Status member of each NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure in the state tree.

Requirements

Header

Ndischimney.h (include Ndischimney.h)

See also

MiniportInitiateOffload
MiniportInvalidateOffload
MiniportQueryOffload
MiniportTerminateOffload
MiniportUpdateOffload
NEIGHBOR_OFFLOAD_STATE_CACHED
NEIGHBOR_OFFLOAD_STATE_DELEGATED
NdisMAllocatePort
NdisMInitiateOffloadComplete
NdisMInvalidateOffloadComplete
NdisMQueryOffloadStateComplete
NdisMTerminateOffloadComplete
NdisMUpdateOffloadComplete
NDIS_OBJECT_HEADER
NdisTcpOffloadEventHandler
NdisTcpOffloadReceiveHandler
PATH_OFFLOAD_STATE_CACHED
PATH_OFFLOAD_STATE_CONST
PATH_OFFLOAD_STATE_DELEGATED
TCP_OFFLOAD_STATE_CACHED
TCP_OFFLOAD_STATE_CONST
TCP_OFFLOAD_STATE_DELEGATED

 

 

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