EVT_WDF_IO_QUEUE_STATE callback function (wdfio.h)

[Applies to KMDF and UMDF]

A driver's EvtIoQueueState event callback function delivers queue state information to the driver.

Syntax

EVT_WDF_IO_QUEUE_STATE EvtWdfIoQueueState;

void EvtWdfIoQueueState(
  [in] WDFQUEUE Queue,
  [in] WDFCONTEXT Context
)
{...}

Parameters

[in] Queue

A handle to an I/O queue object.

[in] Context

Driver-defined context information that the driver specified when it registered the EvtIoQueueState callback function.

Return value

None

Remarks

Drivers can register an EvtIoQueueState callback function by specifying its address as input to WdfIoQueueStop, WdfIoQueueDrain, WdfIoQueuePurge, or WdfIoQueueReadyNotify. The framework calls the EvtIoQueueState callback function after the specified operation completes.

The EvtIoQueueState callback function can be called at IRQL <= DISPATCH_LEVEL, unless the ExecutionLevel member of the queue's WDF_OBJECT_ATTRIBUTES is set to WdfExecutionLevelPassive, in which case it is called at IRQL = PASSIVE_LEVEL. If the queue specifies WdfExecutionLevelInheritFromParent, the property can be inherited from the WDFDEVICE or WDFDRIVER's WDF_OBJECT_ATTRIBUTES.

If the IRQL is PASSIVE_LEVEL, the framework calls the callback function within a critical region.

Requirements

See also

WDF_OBJECT_ATTRIBUTES

WdfIoQueueDrain

WdfIoQueuePurge

WdfIoQueueReadyNotify

WdfIoQueueStop