IoCsqInitializeEx function (wdm.h)
The IoCsqInitializeEx routine initializes the dispatch table for a cancel-safe IRP queue.
Syntax
NTSTATUS IoCsqInitializeEx(
[out] PIO_CSQ Csq,
[in] PIO_CSQ_INSERT_IRP_EX 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 IoCsqInitializeEx.
[in] CsqInsertIrp
Pointer to the driver-defined CsqInsertIrpEx 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
IoCsqInitializeEx returns STATUS_SUCCESS on success, or the appropriate error code on failure.
Remarks
The IoCsqInitialize and IoCsqInitializeEx routines initialize an IO_CSQ structure that describes a driver's cancel-safe IRP queue. You can use IoCsqInitializeEx to specify an IRP queue with extended capabilities instead of one specified by IoCsqInitialize:
- The driver implements a CsqInsertIrpEx routine rather than a CsqInsertIrp routine. CsqInsertIrpEx takes an additional parameter, InsertContext. When the driver calls IoCsqInsertIrpEx to insert the IRP, it specifies the value that is passed as InsertContext.
- IoCsqInsertIrpEx returns the return value of CsqInsertIrpEx. Drivers can use the return value to indicate whether an insert operation succeeded or failed.
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 Server 2003 and later versions of the Windows operating system. The routine is also available in the Csq.lib library that ships with the Windows Driver Kit (WDK) and the Driver Development Kit (DDK) for Windows Server 2003. Drivers that must also work on Windows XP, 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 |