FltEnlistInTransaction function (fltkernel.h)

Article
10/21/2021

The FltEnlistInTransaction routine enlists a minifilter driver in a given transaction.

Syntax

NTSTATUS FLTAPI FltEnlistInTransaction(
  [in] PFLT_INSTANCE     Instance,
  [in] PKTRANSACTION     Transaction,
  [in] PFLT_CONTEXT      TransactionContext,
  [in] NOTIFICATION_MASK NotificationMask
);

Parameters

[in] Instance

An opaque instance pointer for the caller. This parameter is required and cannot be NULL.

[in] Transaction

An opaque transaction pointer for the transaction.

[in] TransactionContext

A pointer to the minifilter driver's transaction context. This parameter is required and cannot be NULL.

[in] NotificationMask

Specifies the type of notifications that the filter manager is to send to the minifilter driver, as one or more of the values listed in the following table. This parameter is required and cannot be zero.

Value	Meaning
TRANSACTION_NOTIFY_COMMIT	This notification is sent when the transaction is being committed.
TRANSACTION_NOTIFY_COMMIT_FINALIZE	For Windows Vista SP1 and later, this notification is sent when the transaction is fully committed (that is, when all of the resource managers associated with the transaction, such as TxF, have committed).
TRANSACTION_NOTIFY_PREPARE	This notification is sent when the transaction has entered the prepare for commit phase.
TRANSACTION_NOTIFY_PREPREPARE	This notification is sent when the transaction has entered the pre-prepare for commit phase.
TRANSACTION_NOTIFY_ROLLBACK	This notification is sent when the transaction is being rolled back or aborted.
FLT_MAX_TRANSACTION_NOTIFICATIONS	TRANSACTION_NOTIFY_COMMIT \| TRANSACTION_NOTIFY_PREPARE \| TRANSACTION_NOTIFY_PREPREPARE \| TRANSACTION_NOTIFY_ROLLBACK

Return value

FltEnlistInTransaction returns STATUS_SUCCESS or an appropriate NTSTATUS value such as one of the following:

Return code	Description
STATUS_FLT_ALREADY_ENLISTED	The caller is already enlisted in the transaction. This is an error code.
STATUS_FLT_DELETING_OBJECT	The instance specified in the Instance parameter is being torn down. This is an error code.
STATUS_INSUFFICIENT_RESOURCES	FltEnlistInTransaction encountered a pool allocation error. This is an error code.
STATUS_INVALID_PARAMETER	The caller did not register a TransactionNotificationCallback routine. This is an error code.
STATUS_INVALID_PARAMETER_4	The caller specified an invalid value for the NotificationMask parameter. This is an error code.

Remarks

A minifilter driver calls FltEnlistInTransaction to enlist in a transaction. Before calling FltEnlistInTransaction, the minifilter driver must have registered a TransactionNotificationCallback routine. Otherwise, the call to FltEnlistInTransaction will fail.

To register a TransactionNotificationCallback routine, a minifilter driver stores the address of a routine of type PFLT_TRANSACTION_NOTIFICATION_CALLBACK in the TransactionNotificationCallback member of the FLT_REGISTRATION structure that the minifilter driver passes as the Registration parameter of FltRegisterFilter.

To roll back or abort a transaction, call FltRollbackEnlistment.

To allocate a new transaction context, call FltAllocateContext.

To retrieve a transaction context, call FltGetTransactionContext.

To delete a transaction context, call FltDeleteTransactionContext or FltDeleteContext.

To set a transaction context, call FltSetTransactionContext.

Requirements

Requirement	Value
Minimum supported client	This routine is available on Windows Vista and later versions of Windows.
Target Platform	Universal
Header	fltkernel.h (include Fltkernel.h)
Library	FltMgr.lib
DLL	FltMgr.sys
IRQL	<= APC_LEVEL