StorPortGetPfns function (storport.h)
A miniport can call the StorPortGetPfns to retrieve the page frame numbers (Pfns) for the memory described by the specified MDL (memory descriptor list) associated with a SRB.
Syntax
ULONG StorPortGetPfns(
[in] PVOID HwDeviceExtension,
[in] PSCSI_REQUEST_BLOCK Srb,
[in] PVOID Mdl,
[out] PVOID *Pfns,
[out] ULONG *PfnCount,
[out] ULONG *StartingOffset
);
Parameters
[in] HwDeviceExtension
A pointer to the hardware device extension. This is a per HBA storage area that the port driver allocates and initializes on behalf of the miniport driver.
Miniport drivers usually store HBA-specific information in this extension, such as the state of the HBA and the mapped access ranges for the HBA. This area is available to the miniport driver in the DeviceExtension->HwDeviceExtension member of the device object for the HBA immediately after the miniport driver calls StorPortInitialize. The port driver frees this memory when it removes the device.
[in] Srb
A pointer to the source SCSI request block (SRB). Starting in Windows 8, the Srb parameter can point to either SCSI_REQUEST_BLOCK or STORAGE_REQUEST_BLOCK.
[in] Mdl
A pointer to the MDL for which Pfns are requested. Only MDLs obtained using StorPortGetOriginalMdl or StorPortGetDataInBufferMdl are supported.
[out] Pfns
Pointer to an array of Pfns that are associated with the MDL. Callers must not modify, update, or free the list.
[out] PfnCount
The number of Pfns in the array that Pfns points to.
[out] StartingOffset
Specifies the byte offset within the initial page of the buffer described by the given MDL.
Return value
StorPortGetPfns returns one of the following status codes:
| Return code | Description |
|---|---|
| STOR_STATUS_NOT_IMPLEMENTED | This function is not implemented on the active operating system. |
| STOR_STATUS_SUCCESS | The function completed successfully. |
| STOR_STATUS_INVALID_PARAMETER | A pointer to one of the parameters is NULL. |
Requirements
| Requirement | Value |
|---|---|
| Target Platform | Universal |
| Header | storport.h |