NET_BUFFER_LIST_POOL_PARAMETERS structure (ndis/nblapi.h)

Article
05/31/2022

The NET_BUFFER_LIST_POOL_PARAMETERS structure defines the parameters for a pool of NET_BUFFER_LIST structures.

Syntax

typedef struct _NET_BUFFER_LIST_POOL_PARAMETERS {
  NDIS_OBJECT_HEADER Header;
  UCHAR              ProtocolId;
  BOOLEAN            fAllocateNetBuffer;
  USHORT             ContextSize;
  ULONG              PoolTag;
  ULONG              DataSize;
  ULONG              Flags;
} NET_BUFFER_LIST_POOL_PARAMETERS, *PNET_BUFFER_LIST_POOL_PARAMETERS;

Members

Header

The type, revision, and size of the NET_BUFFER_LIST_POOL_PARAMETERS structure. This member is formatted as an NDIS_OBJECT_HEADER structure.

The miniport driver must set the Type member of Header to NDIS_OBJECT_TYPE_DEFAULT. To specify the version of the NET_BUFFER_LIST_POOL_PARAMETERS structure, the driver must set the Revision member of Header to the following value:

NET_BUFFER_LIST_POOL_PARAMETERS_REVISION_1

Original version for NDIS 6.0.

Set the Size member to NDIS_SIZEOF_NET_BUFFER_LIST_POOL_PARAMETERS_REVISION_1.

ProtocolId

The type of caller. Miniport, filter, and intermediate drivers set this field to zero (NDIS_PROTOCOL_ID_DEFAULT). Protocol drivers use one of the following values:

NDIS_PROTOCOL_ID_DEFAULT

Specifies a default protocol driver identifier.

NDIS_PROTOCOL_ID_TCP_IP

Specifies the TCP/IP protocol.

NDIS_PROTOCOL_ID_IPX

Specifies the IPX protocol.

NDIS_PROTOCOL_ID_NBF

Specifies the NetBEUI protocol.

fAllocateNetBuffer

If this member is set to TRUE, NDIS allocates a pool of NET_BUFFER_LIST structures. Each allocated NET_BUFFER_LIST structure is initialized with one NET_BUFFER structure.

If this member is set to FALSE, NDIS allocates a pool of NET_BUFFER_LIST structures. Each allocated NET_BUFFER_LIST structure is not initialized to contain any NET_BUFFER structures.

For more information, see the Remarks section.

ContextSize

The size, in bytes, of the preallocated NET_BUFFER_LIST_CONTEXT structure data that NDIS should provide for the NET_BUFFER_LIST structures in this pool. The ContextSize must be a multiple of the value that is defined by MEMORY_ALLOCATION_ALIGNMENT.

PoolTag

A kernel pool tag that the caller uses when it allocates NET_BUFFER_LIST structures from this pool. The tag is a string, delimited by single quotation marks, with up to four characters, usually specified in reversed order. The kernel pool tag helps NDIS to identify the owner of the NET_BUFFER_LIST structures that are allocated from this pool.

DataSize

The default data size, in bytes, for data buffers that are associated with this NET_BUFFER_LIST pool, if any. NDIS uses this value to set the size of any data buffers that it allocates for any associated NET_BUFFER structures.

For more information, see the Remarks section.

Flags

The following flag is defined:

NET_BUFFER_LIST_POOL_FLAG_VERIFY 0x00000001

If this flag is set, NDIS will not immediately reuse NET_BUFFER_LISTs from this pool. Instead, allocations will be marked as no-access when they are freed so that drivers can detect use-after-free bugs.

Remarks

If fAllocateNetBuffer is set to FALSE, NDIS will not allocate NET_BUFFER structures, and DataSize should be set to zero.

If DataSize is not zero, fAllocateNetBuffer must be set to TRUE. This causes NDIS to allocate the NET_BUFFER structure with a data buffer of the specified size.

If DataSize is zero and fAllocateNetBuffer is TRUE, NDIS allocates the NET_BUFFER structure but not the data buffer.

The Parameters parameter of the NdisAllocateNetBufferListPool function contains a pointer to an NET_BUFFER_LIST_POOL_PARAMETERS structure.

Requirements

Requirement	Value
Minimum supported client	Supported in NDIS 6.0 and later.
Header	ndis/nblapi.h (include ndis.h)