WdfCmResourceListRemoveByDescriptor function (wdfresource.h)

Article
02/22/2024

[Applies to KMDF only]

The WdfCmResourceListRemoveByDescriptor method removes a specified resource descriptor from a specified resource list.

Syntax

void WdfCmResourceListRemoveByDescriptor(
  [in] WDFCMRESLIST                    List,
  [in] PCM_PARTIAL_RESOURCE_DESCRIPTOR Descriptor
);

Parameters

[in] List

A handle to a framework resource-list object that represents a list of hardware resources for a device.

[in] Descriptor

A pointer to an CM_PARTIAL_RESOURCE_DESCRIPTOR structure that describes a hardware resource.

Return value

None

Remarks

A bug check occurs if the driver supplies an invalid object handle.

The WdfCmResourceListRemoveByDescriptor method removes the resource descriptor that matches the Descriptor parameter. To find a match, the method compares the specified resource descriptor with the resource descriptors in the logical configuration, byte for byte.

When WdfCmResourceListRemoveByDescriptor removes the resource descriptor that has the index value n, the index value of the next resource descriptor changes from n+1 to n.

For more information about resource lists, see Hardware Resources for Framework-Based Drivers.

Examples

The following code example searches for port resource descriptors in a device's resource lists. For each port resource that the example finds, it checks to see if the port address is within a certain range. If the port address is outside of the range, the example removes the descriptor from both the raw and translated resource lists.

NTSTATUS
MyEvtDeviceRemoveAddedResources(
    WDFDEVICE Device,
    WDFCMRESLIST ResourcesRaw,
    WDFCMRESLIST ResourcesTranslated
    )
{    
    ULONG i, count;

    pDevExt = DeviceGetExtension(Device);
    count = WdfCmResourceListGetCount(ResourcesRaw);

    for (i = 0; i < count; i++) {
        PCM_PARTIAL_RESOURCE_DESCRIPTOR descriptor;

        descriptor = WdfCmResourceListGetDescriptor(
                                                    ResourcesRaw,
                                                    i
                                                    );

        if (descriptor->Type != CmResourceTypePort) {
            continue;
        }

        if (descriptor->u.Port.Start.QuadPart < pDevExt->Ranges[0].MinAddress ||
             descriptor->u.Port.Start.QuadPart > pDevExt->Ranges[0].MaxAddress)
        {
            WdfCmResourceListRemoveByDescriptor(
                                                ResourcesRaw,
                                                descriptor
                                                );

            // The descriptor may not be the same in the raw and translated resource lists, so use an index for the second removal

            WdfCmResourceListRemove(
                                                ResourcesTranslated,
                                                i
                                                );
            break;
        }
    }
}

Requirements

Requirement	Value
Target Platform	Universal
Minimum KMDF version	1.0
Header	wdfresource.h (include Wdf.h)
Library	Wdf01000.sys (see Framework Library Versioning.)
IRQL	<=DISPATCH_LEVEL
DDI compliance rules	DriverCreate(kmdf), KmdfIrql(kmdf), KmdfIrql2(kmdf), KmdfIrqlExplicit(kmdf)

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