HW_FIND_ADAPTER callback function (storport.h)

Article
10/21/2021

The HwStorFindAdapter routine uses the supplied configuration to determine whether a specific HBA is supported and, if it is, to return configuration information about that adapter.

Syntax

HW_FIND_ADAPTER HwFindAdapter;

ULONG HwFindAdapter(
           PVOID DeviceExtension,
  [in]     PVOID HwContext,
  [in]     PVOID BusInformation,
  [in]     PCHAR ArgumentString,
  [in/out] PPORT_CONFIGURATION_INFORMATION ConfigInfo,
  [in]     PBOOLEAN Reserved3
)
{...}

Parameters

DeviceExtension

Supplies a per adapter storage area.

[in] HwContext

Set to NULL.

[in] BusInformation

Set to NULL.

[in] ArgumentString

Supplies a NULL-terminated string with context information about the driver.

[in/out] ConfigInfo

Supplies an initialized PORT_CONFIGURATION_INFORMATION structure that the miniport driver uses during initialization.

[in] Reserved3

Reserved for system use.

Return value

HwStorFindAdapter must return one of the following status values:

Return code	Description
SP_RETURN_FOUND	Indicates that a supported HBA was found and that the HBA-relevant configuration information was successfully determined and set in the PORT_CONFIGURATION_INFORMATION structure.
SP_RETURN_ERROR	Indicates that an HBA was found but there was an error obtaining the configuration information. If possible, such an error should be logged with StorPortLogError.
SP_RETURN_BAD_CONFIG	Indicates that the supplied configuration information was invalid for the adapter.
SP_RETURN_NOT_FOUND	Indicates that no supported HBA was found for the supplied configuration information.

Remarks

Because the Storport driver supports only Plug and Play (PnP) devices, the HwContext and BusInformation parameters to HwStorFindAdapter are not supplied to non-virtual miniport drivers.

HwStorFindAdapter must set the MaximumTransferLength and NumberOfPhysicalBreaks fields in the ConfigInfo structure. Other than these fields, the PORT_CONFIGURATION_INFORMATION structure will always fully specify all adapter resources that are required to start the adapter.

The name HwStorFindAdapter is just a placeholder. The actual prototype of this routine is defined in Storport.h as follows:

typedef
ULONG
HW_FIND_ADAPTER (
  _In_ PVOID  DeviceExtension,
  _In_ PVOID  HwContext,
  _In_ PVOID  BusInformation,
  _In_z_ PCHAR  ArgumentString,
  _Inout_ PPORT_CONFIGURATION_INFORMATION  ConfigInfo,
  _In_ PBOOLEAN  Reserved3
  );

In most cases StorPort calls the HwStorFindAdapter routine at IRQL == PASSIVE_LEVEL without acquiring any spin locks. The exception case is when the miniport does not support calling HwStorAdaptorControl with the ScsiRestartAdapter control type. In this situation, StorPort will instead reinitialize the adapter by calling both HwStorFindAdapter and HwStorInitialize. When this is the case, HwStorFindAdapter is called at IRQL == DISPATCH_LEVEL. Also, when in dump mode, HwStorFindAdapter is called at IRQL == HIGH_LEVEL.

Examples

To define an HwStorFindAdapter callback function, you must first provide a function declaration that identifies the type of callback function you’re defining. Windows provides a set of callback function types for drivers. Declaring a function using the callback function types helps Code Analysis for Drivers, Static Driver Verifier (SDV), and other verification tools find errors, and it’s a requirement for writing drivers for the Windows operating system.

For example, to define a HwStorFindAdapter callback routine that is named MyHwFindAdapter, use the HW_FIND_ADAPTER type as shown in this code example:

HW_FIND_ADAPTER MyHwFindAdapter;

Then, implement your callback routine as follows:

_Use_decl_annotations_
ULONG
MyHwFindAdapter (
  _In_ PVOID  DeviceExtension,
  _In_ PVOID  HwContext,
  _In_ PVOID  BusInformation,
  _In_z_ PCHAR  ArgumentString,
  _Inout_ PPORT_CONFIGURATION_INFORMATION  ConfigInfo,
  _In_ PBOOLEAN  Reserved3
  );
  {
      ...
  }

The HW_FIND_ADAPTER function type is defined in the Storport.h header file. To more accurately identify errors when you run the code analysis tools, be sure to add the Use_decl_annotations annotation to your function definition. The Use_decl_annotations annotation ensures that the annotations that are applied to the HW_FIND_ADAPTER function type in the header file are used. For more information about the requirements for function declarations, see Declaring Functions Using Function Role Types for Storport Drivers. For information about Use_decl_annotations, see Annotating Function Behavior.

Requirements

Requirement	Value
Target Platform	Universal
Header	storport.h (include Storport.h)
IRQL	PASSIVE_LEVEL (See Remarks section.)

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