IDE_HW_BUILDIO callback function (irb.h)

The IdeHwBuildIo miniport driver routine is called one time for every incoming I/O request.

Note  The ATA port driver and ATA miniport driver models may be altered or unavailable in the future. Instead, we recommend using the Storport driver and Storport miniport driver models.

 

Syntax

IDE_HW_BUILDIO IdeHwBuildio;

BOOLEAN IdeHwBuildio(
  [in] PVOID ChannelExtension,
  [in] PIDE_REQUEST_BLOCK Irb
)
{...}

Parameters

[in] ChannelExtension

A pointer to the miniport driver channel extension.

[in] Irb

A pointer to a structure of type IDE_REQUEST_BLOCK that defines the Integrated Device Electronics (IDE) input/output request block (IRB) to process.

Return value

IdeHwBuildIo returns TRUE to acknowledge the receipt of the IDE_REQUEST_BLOCK structure. The port driver ignores a return value of FALSE.

Remarks

Miniport drivers provide an AtaHwBuildlo routine that performs unsynchronized I/O processing with interrupts enabled. After IdeHwBuildIo completes all unsynchronized processing of a request, it returns to the port driver, and the port driver passes the request to the miniport driver's IdeHwStartIo routine, which performs the tasks that require synchronization.

The miniport driver must observe certain restrictions while it executes the IdeHwBuildIo routine. The miniport driver calls IdeHwBuildIo without holding any locks. In particular, the miniport driver must not touch any shared data in its channel extension, nor can it call any of the routines exported by the ATA port driver.

If the miniport driver must complete a request while it executes the IdeHwBuildIo routine, it must assign the appropriate completion status value to the IrbStatus member of the IDE_REQUEST_BLOCK structure pointed to by the Irb parameter. The miniport driver must not set IrbStatus to a value of IRB_STATUS_PENDING.

The miniport driver can use the IdeHwBuildIo routine to indicate to the port driver how an IRB should be handled. For example, the miniport driver can request that the port driver map the buffer at DataBuffer by setting the IrbFlags member of the IRB to the appropriate value. The miniport driver should not request that the buffer that is associated with a request be mapped unless the request is some type of data transfer.

The IdeHwBuildIo routine resembles Storport's HwStorBuildIo routine in functionality. For more information about the HwStorBuildIo routine, see Unsynchronized HwStorBuildIo Routine.

IdeHwBuildIo is an optional routine.

Requirements

Requirement	Value
Target Platform	Desktop
Header	irb.h (include Irb.h)

See also

IDE_REQUEST_BLOCK

IdeHwStartIo