IoCallDriver function

The IoCallDriver routine sends an IRP to the driver associated with a specified device object.

Syntax

void IoCallDriver(
   a,
   b
);

Parameters

a

Pointer to a device object, representing the target device for the requested I/O operation.

b

Pointer to the IRP.

Return Value

None

Remarks

Before calling IoCallDriver, the calling driver must set up the I/O stack location in the IRP for the target driver. For more information, see Passing IRPs Down the Driver Stack.

IoCallDriver assigns the DeviceObject input parameter to the DeviceObject member of the IO_STACK_LOCATION structure for the driver being called.

An IRP passed in a call to IoCallDriver becomes inaccessible to the higher-level driver, unless the higher-level driver has called IoSetCompletionRoutine to set up an IoCompletion routine for the IRP. If it has, the IRP input to the IoCompletion routine has its I/O status block set by the lower drivers, and all lower-level drivers' I/O stack locations are filled with zeros.

Drivers for Windows Server 2003, Windows XP, and Windows 2000 must use PoCallDriver rather than IoCallDriver to pass power IRPs (IRP_MJ_POWER). For more information, see Calling IoCallDriver vs. Calling PoCallDriver.

Requirements

   
Windows version Available starting with Windows 2000.
Target Platform Universal
Header wdm.h (include Wdm.h, Ntddk.h, Ntifs.h)
Library NtosKrnl.lib
DLL NtosKrnl.exe
IRQL "<= DISPATCH_LEVEL"
DDI compliance rules CompleteRequestStatusCheck, CompletionRoutineRegistered, DeleteDevice, ForwardedAtBadIrql, ForwardedAtBadIrqlAllocate, ForwardedAtBadIrqlFsdAsync, ForwardedAtBadIrqlFsdSync, IoAllocateForward, IoAllocateIrpSignalEventInCompletionTimeout, IoBuildDeviceControlWait, IoBuildDeviceControlWaitTimeout, IoBuildFsdForward, IoBuildSynchronousFsdRequestWait, IoBuildSynchronousFsdRequestWaitTimeout, IoSetCompletionRoutineExCheck, IrpProcessingComplete, LowerDriverReturn, MarkDevicePower, MarkingQueuedIrps, MarkIrpPending, MarkIrpPending2, MarkPower, MarkPowerDown, MarkQueryRelations, MarkStartDevice, PendedCompletedRequest, PendedCompletedRequest2, PendedCompletedRequest3, PendedCompletedRequestEx, PnpIrpCompletion, PowerDownFail, PowerUpFail, RemoveLockForward, RemoveLockForward2, RemoveLockForwardDeviceControl, RemoveLockForwardDeviceControl2, RemoveLockForwardDeviceControlInternal, RemoveLockForwardDeviceControlInternal2, RemoveLockForwardRead, RemoveLockForwardRead2, RemoveLockForwardWrite, RemoveLockForwardWrite2, RemoveLockMnRemove2, RemoveLockMnSurpriseRemove, RemoveLockQueryMnRemove, TargetRelationNeedsRef, WmiForward, HwStorPortProhibitedDDIs

See Also

IoAllocateIrp

IoBuildAsynchronousFsdRequest

IoBuildDeviceIoControlRequest

IoBuildSynchronousFsdRequest

IoSetCompletionRoutine

PoCallDriver