NDIS_MINIPORT_OFFLOAD_BLOCK_LIST structure (ndischimney.h)
[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 {
IN NDIS_OBJECT_HEADER Header;
IN _NDIS_MINIPORT_OFFLOAD_BLOCK_LIST *NextBlock;
#if ...
struct _NDIS_MINIPORT_OFFLOAD_BLOCK_LIST;
IN _NDIS_MINIPORT_OFFLOAD_BLOCK_LIST *DependentBlockList;
#else
struct _NDIS_MINIPORT_OFFLOAD_BLOCK_LIST;
#endif
OUT NDIS_STATUS Status;
IN PVOID NdisReserved[2];
IN OUT PVOID *MiniportOffloadContext;
IN NDIS_HANDLE NdisOffloadHandle;
IN PVOID ProtocolReserved[2];
IN PVOID MiniportReserved[2];
IN PVOID ImReserved[2];
IN PVOID Scratch[2];
IN PVOID SourceHandle;
IN NDIS_PORT_NUMBER PortNumber;
IN OUT 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.
_NDIS_MINIPORT_OFFLOAD_BLOCK_LIST
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.
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[2]
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[2]
Reserved for use by protocol drivers, which can use this area for their own purposes. Offload targets must not modify this value.
MiniportReserved[2]
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[2]
Reserved for use by intermediate drivers, which can use this area for their own purposes. Offload targets must not modify this value.
Scratch[2]
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:
- NdisMInitiateOffloadComplete
- NdisMQueryOffloadStateComplete
- NdisMInvalidateOffloadComplete
- NdisMTerminateOffloadComplete
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
| Requirement | Value |
|---|---|
| Header | ndischimney.h (include Ndischimney.h) |