lockctrl.c

来自「winddk src目录下的文件系统驱动源码压缩!」· C语言 代码 · 共 712 行 · 第 1/2 页

FatFastUnlockAll (
    IN PFILE_OBJECT FileObject,
    PEPROCESS ProcessId,
    OUT PIO_STATUS_BLOCK IoStatus,
    IN PDEVICE_OBJECT DeviceObject
    )

/*++

Routine Description:

    This is a call back routine for doing the fast unlock all call.

Arguments:

    FileObject - Supplies the file object used in this operation

    ProcessId - Supplies the process ID used in this operation

    Status - Receives the Status if this operation is successful

Return Value:

    BOOLEAN - TRUE if this operation completed and FALSE if caller
        needs to take the long route.

--*/

{
    BOOLEAN Results;
    PVCB Vcb;
    PFCB Fcb;
    PCCB Ccb;

    DebugTrace(+1, Dbg, "FatFastUnlockAll\n", 0);

    IoStatus->Information = 0;

    //
    //  Decode the type of file object we're being asked to process and make sure
    //  it is only a user file open.
    //

    if (FatDecodeFileObject( FileObject, &Vcb, &Fcb, &Ccb ) != UserFileOpen) {

        IoStatus->Status = STATUS_INVALID_PARAMETER;

        DebugTrace(-1, Dbg, "FatFastUnlockAll -> TRUE (STATUS_INVALID_PARAMETER)\n", 0);
        return TRUE;
    }

    //
    //  Acquire exclusive access to the Fcb this operation can always wait
    //

    FsRtlEnterFileSystem();

    (VOID) ExAcquireResourceSharedLite( Fcb->Header.Resource, TRUE );

    try {

        //
        //  We check whether we can proceed based on the state of the file oplocks.
        //

        if (!FsRtlOplockIsFastIoPossible( &(Fcb)->Specific.Fcb.Oplock )) {

            try_return( Results = FALSE );
        }

        //
        //  Now call the FsRtl routine to do the actual processing of the
        //  Lock request.  The call will always succeed.
        //

        Results = TRUE;
        IoStatus->Status = FsRtlFastUnlockAll( &Fcb->Specific.Fcb.FileLock,
                                               FileObject,
                                               ProcessId,
                                               NULL );

        //
        //  Set the flag indicating if Fast I/O is possible
        //

        Fcb->Header.IsFastIoPossible = FatIsFastIoPossible( Fcb );

    try_exit:  NOTHING;
    } finally {

        DebugUnwind( FatFastUnlockAll );

        //
        //  Release the Fcb, and return to our caller
        //

        ExReleaseResourceLite( (Fcb)->Header.Resource );

        FsRtlExitFileSystem();

        DebugTrace(-1, Dbg, "FatFastUnlockAll -> %08lx\n", Results);
    }

    return Results;
}


BOOLEAN
FatFastUnlockAllByKey (
    IN PFILE_OBJECT FileObject,
    PVOID ProcessId,
    ULONG Key,
    OUT PIO_STATUS_BLOCK IoStatus,
    IN PDEVICE_OBJECT DeviceObject
    )

/*++

Routine Description:

    This is a call back routine for doing the fast unlock all by key call.

Arguments:

    FileObject - Supplies the file object used in this operation

    ProcessId - Supplies the process ID used in this operation

    Key - Supplies the key used in this operation

    Status - Receives the Status if this operation is successful

Return Value:

    BOOLEAN - TRUE if this operation completed and FALSE if caller
        needs to take the long route.

--*/

{
    BOOLEAN Results;
    PVCB Vcb;
    PFCB Fcb;
    PCCB Ccb;

    DebugTrace(+1, Dbg, "FatFastUnlockAllByKey\n", 0);

    IoStatus->Information = 0;

    //
    //  Decode the type of file object we're being asked to process and make sure
    //  it is only a user file open.
    //

    if (FatDecodeFileObject( FileObject, &Vcb, &Fcb, &Ccb ) != UserFileOpen) {

        IoStatus->Status = STATUS_INVALID_PARAMETER;

        DebugTrace(-1, Dbg, "FatFastUnlockAll -> TRUE (STATUS_INVALID_PARAMETER)\n", 0);
        return TRUE;
    }

    //
    //  Acquire exclusive access to the Fcb this operation can always wait
    //

    FsRtlEnterFileSystem();

    (VOID) ExAcquireResourceSharedLite( Fcb->Header.Resource, TRUE );

    try {

        //
        //  We check whether we can proceed based on the state of the file oplocks.
        //

        if (!FsRtlOplockIsFastIoPossible( &(Fcb)->Specific.Fcb.Oplock )) {

            try_return( Results = FALSE );
        }

        //
        //  Now call the FsRtl routine to do the actual processing of the
        //  Lock request.  The call will always succeed.
        //

        Results = TRUE;
        IoStatus->Status = FsRtlFastUnlockAllByKey( &Fcb->Specific.Fcb.FileLock,
                                                    FileObject,
                                                    ProcessId,
                                                    Key,
                                                    NULL );

        //
        //  Set the flag indicating if Fast I/O is possible
        //

        Fcb->Header.IsFastIoPossible = FatIsFastIoPossible( Fcb );

    try_exit:  NOTHING;
    } finally {

        DebugUnwind( FatFastUnlockAllByKey );

        //
        //  Release the Fcb, and return to our caller
        //

        ExReleaseResourceLite( (Fcb)->Header.Resource );

        FsRtlExitFileSystem();

        DebugTrace(-1, Dbg, "FatFastUnlockAllByKey -> %08lx\n", Results);
    }

    return Results;
}


NTSTATUS
FatCommonLockControl (
    IN PIRP_CONTEXT IrpContext,
    IN PIRP Irp
    )

/*++

Routine Description:

    This is the common routine for doing Lock control operations called
    by both the fsd and fsp threads

Arguments:

    Irp - Supplies the Irp to process

Return Value:

    NTSTATUS - The return status for the operation

--*/

{
    NTSTATUS Status;
    PIO_STACK_LOCATION IrpSp;

    TYPE_OF_OPEN TypeOfOpen;

    PVCB Vcb;
    PFCB Fcb;
    PCCB Ccb;

    BOOLEAN OplockPostIrp = FALSE;

    //
    //  Get a pointer to the current Irp stack location
    //

    IrpSp = IoGetCurrentIrpStackLocation( Irp );

    DebugTrace(+1, Dbg, "FatCommonLockControl\n", 0);
    DebugTrace( 0, Dbg, "Irp           = %08lx\n", Irp);
    DebugTrace( 0, Dbg, "MinorFunction = %08lx\n", IrpSp->MinorFunction);

    //
    //  Decode the type of file object we're being asked to process
    //

    TypeOfOpen = FatDecodeFileObject( IrpSp->FileObject, &Vcb, &Fcb, &Ccb );

    //
    //  If the file is not a user file open then we reject the request
    //  as an invalid parameter
    //

    if (TypeOfOpen != UserFileOpen) {

        FatCompleteRequest( IrpContext, Irp, STATUS_INVALID_PARAMETER );

        DebugTrace(-1, Dbg, "FatCommonLockControl -> STATUS_INVALID_PARAMETER\n", 0);
        return STATUS_INVALID_PARAMETER;
    }

    //
    //  Acquire exclusive access to the Fcb and enqueue the Irp if we didn't
    //  get access
    //

    if (!FatAcquireSharedFcb( IrpContext, Fcb )) {

        Status = FatFsdPostRequest( IrpContext, Irp );

        DebugTrace(-1, Dbg, "FatCommonLockControl -> %08lx\n", Status);
        return Status;
    }

    try {

        //
        //  We check whether we can proceed
        //  based on the state of the file oplocks.
        //

        Status = FsRtlCheckOplock( &Fcb->Specific.Fcb.Oplock,
                                   Irp,
                                   IrpContext,
                                   FatOplockComplete,
                                   NULL );

        if (Status != STATUS_SUCCESS) {

            OplockPostIrp = TRUE;
            try_return( NOTHING );
        }

        //
        //  Now call the FsRtl routine to do the actual processing of the
        //  Lock request
        //

        Status = FsRtlProcessFileLock( &Fcb->Specific.Fcb.FileLock, Irp, NULL );

        //
        //  Set the flag indicating if Fast I/O is possible
        //

        Fcb->Header.IsFastIoPossible = FatIsFastIoPossible( Fcb );

    try_exit:  NOTHING;
    } finally {

        DebugUnwind( FatCommonLockControl );

        //
        //  Only if this is not an abnormal termination do we delete the
        //  irp context
        //

        if (!AbnormalTermination() && !OplockPostIrp) {

            FatCompleteRequest( IrpContext, FatNull, 0 );
        }

        //
        //  Release the Fcb, and return to our caller
        //

        FatReleaseFcb( IrpContext, Fcb );

        DebugTrace(-1, Dbg, "FatCommonLockControl -> %08lx\n", Status);
    }

    return Status;
}