IoCsqInitialize function (wdm.h)

Article
02/22/2024

The IoCsqInitialize routine initializes the driver's cancel-safe IRP queue dispatch table.

Syntax

NTSTATUS IoCsqInitialize(
  [out] PIO_CSQ                       Csq,
  [in]  PIO_CSQ_INSERT_IRP            CsqInsertIrp,
  [in]  PIO_CSQ_REMOVE_IRP            CsqRemoveIrp,
  [in]  PIO_CSQ_PEEK_NEXT_IRP         CsqPeekNextIrp,
  [in]  PIO_CSQ_ACQUIRE_LOCK          CsqAcquireLock,
  [in]  PIO_CSQ_RELEASE_LOCK          CsqReleaseLock,
  [in]  PIO_CSQ_COMPLETE_CANCELED_IRP CsqCompleteCanceledIrp
);

Parameters

[out] Csq

Pointer to the IO_CSQ structure to be initialized by IoCsqInitialize.

[in] CsqInsertIrp

Pointer to the driver-defined CsqInsertIrp function for the driver's cancel-safe IRP queue.

[in] CsqRemoveIrp

Pointer to the driver-defined CsqRemoveIrp function for the driver's cancel-safe IRP queue.

[in] CsqPeekNextIrp

Pointer to the driver-defined CsqPeekNextIrp function for the driver's cancel-safe IRP queue.

[in] CsqAcquireLock

Pointer to the driver-defined CsqAcquireLock function for the driver's cancel-safe IRP queue.

[in] CsqReleaseLock

Pointer to the driver-defined CsqReleaseLock function for the driver's cancel-safe IRP queue.

[in] CsqCompleteCanceledIrp

Pointer to the driver-defined CsqCompleteCanceledIrp function for the driver's cancel-safe IRP queue.

Return value

This routine returns STATUS_SUCCESS on success, or the appropriate NTSTATUS error code on failure.

Remarks

The IoCsqInitialize routine initializes an IO_CSQ structure that describes a driver's cancel-safe IRP queue. Drivers can also use IoCsqInitializeEx to create an IRP queue with extended capabilities. For more information, see Cancel-Safe IRP Queues.

Note that IoCsqXxx routines use the DriverContext[3] member of the IRP to hold IRP context information. Drivers that use these routines to queue IRPs must leave that member unused.

Requirements

Requirement	Value
Minimum supported client	Available in Windows XP and later versions of the Windows operating system. Drivers that must also work for Windows 2000 and Windows 98/Me can instead link to Csq.lib to use the routine.
Target Platform	Universal
Header	wdm.h (include Wdm.h, Ntddk.h, Ntifs.h)
Library	NtosKrnl.lib
DLL	NtosKrnl.exe
IRQL	Any level