DispatchCleanup routine

The DispatchCleanup routine services IRPs containing the IRP_MJ_CLEANUP I/O function code.


DRIVER_DISPATCH DispatchCleanup;

NTSTATUS DispatchCleanup(
  _Inout_ struct _DEVICE_OBJECT *DeviceObject,
  _Inout_ struct _IRP           *Irp
{ ... }


DeviceObject [in, out]

Caller-supplied pointer to a DEVICE_OBJECT structure. This is the device object for the target device, previously created by the driver's AddDevice routine.

Irp [in, out]

Caller-supplied pointer to an IRP structure that describes the requested I/O operation.

Return value

If the routine succeeds, it must return STATUS_SUCCESS. Otherwise, it must return one of the error status values defined in Ntstatus.h.


A driver's DispatchCleanup routine should be named XxxDispatchCleanup, where Xxx is a driver-specific prefix. The driver's DriverEntry routine must store the DispatchCleanup routine's address in DriverObject->MajorFunction[IRP_MJ_CLEANUP].

Input parameters for all Dispatch routines are supplied in the IRP structure pointed to by Irp. Additional parameters are supplied in the driver's associated I/O stack location, which is described by the IO_STACK_LOCATION structure and can be obtained by calling IoGetCurrentIrpStackLocation.

Generally, all Dispatch routines execute in an arbitrary thread context at IRQL = PASSIVE_LEVEL, but there are exceptions. For more information, see Dispatch Routines and IRQLs.

For more information about DispatchCleanup routines, see Writing Dispatch Routines. For more information about IRPs, see Handling IRPs.


To define a DispatchCleanup callback routine, you must first provide a function declaration that identifies the type of callback routine 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 DispatchCleanup callback routine that is named MyDispatchCleanup, use the DRIVER_DISPATCH type as shown in this code example:

DRIVER_DISPATCH MyDispatchCleanup;

Then, implement your callback routine as follows:

    struct _DEVICE_OBJECT  *DeviceObject,
    struct _IRP  *Irp
      // Function body

The DRIVER_DISPATCH function type is defined in the Wdm.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 DRIVER_DISPATCH function type in the header file are used. For more information about the requirements for function declarations, see Declaring Functions by Using Function Role Types for WDM Drivers. For information about _Use_decl_annotations_, see Annotating Function Behavior.


Target platform



Wdm.h (include Wdm.h, Ntddk.h, or Ntifs.h)


Called at PASSIVE_LEVEL (see Remarks section).



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