NdisQueryMdl macro

The NdisQueryMdl macro retrieves the buffer length, and optionally the base virtual address, from an MDL.

Syntax

VOID NdisQueryMdl(
    _Mdl,
    _VirtualAddress,
    _Length,
    _Priority
);

Parameters

_Mdl
指向 MDL 的指针。

_VirtualAddress
指向调用方提供的变量的指针，在该变量中，此宏返回 MDL 描述的虚拟地址范围的基虚拟地址。 The base virtual address can be NULL for either of the following reasons:

• System resources are low or exhausted and the _Priority parameter is set to LowPagePriority or NormalPagePriority.

• System resources are exhausted and the _Priority parameter is set to HighPagePriority.

_Length
指向调用方提供的变量的指针，在该变量中，此宏返回 MDL 描述的虚拟地址范围的长度（以字节为单位）。

_Priority
页面优先级值。 For a list of the possible values for this parameter, see the Priority parameter of the MmGetSystemAddressForMdlSafe macro.

Return value

None

Remarks

The NdisQueryMdl macro provides an MDL-based version of the NdisQueryBuffer function.

Requirements

See also

MmGetSystemAddressForMdlSafe

NdisQueryBuffer