FltFsControlFile function

The FltFsControlFile routine sends a control code directly to a specified file system or file system filter driver, causing the corresponding driver to perform the specified action.

Syntax

NTSTATUS FLTAPI FltFsControlFile(
  PFLT_INSTANCE Instance,
  PFILE_OBJECT  FileObject,
  ULONG         FsControlCode,
  PVOID         InputBuffer,
  ULONG         InputBufferLength,
  PVOID         OutputBuffer,
  ULONG         OutputBufferLength,
  PULONG        LengthReturned
);

Parameters

Instance

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

FileObject

File object pointer for the file or directory that is the target of this request. This parameter is required and cannot be NULL.

FsControlCode

FSCTL_XXX code that indicates which file system operation is to be carried out. The value of this parameter determines the formats and required lengths of the InputBuffer and OutputBuffer, and it determines which of the following parameter pairs (InputBuffer and InputBufferLength, OutputBuffer and OutputBufferLength) is required.

InputBuffer

Pointer to a caller-allocated input buffer that contains device-specific information to be given to the target driver. If the FsControlCode parameter specifies an operation that does not require input data, this parameter is optional and can be NULL.

InputBufferLength

Size, in bytes, of the buffer at InputBuffer. This value is ignored if InputBuffer is NULL.

OutputBuffer

Pointer to a caller-allocated output buffer in which information is returned from the target driver. If the FsControlCode parameter specifies an operation that does not require output data, this parameter is optional and can be NULL.

OutputBufferLength

Size, in bytes, of the buffer at OutputBuffer. This value is ignored if OutputBuffer is NULL.

LengthReturned

Pointer to a caller-allocated variable that receives the size, in bytes, of the information returned in the buffer at OutputBuffer. This parameter is optional and can be NULL.

Return Value

FltFsControlFile returns STATUS_SUCCESS or an appropriate NTSTATUS value.

Remarks

Minifilter drivers should call this routine instead of ZwFsControlFile.

The following FSCTL codes are currently documented for kernel-mode drivers:

FSCTL_DELETE_REPARSE_POINT

FSCTL_GET_REPARSE_POINT

FSCTL_OPBATCH_ACK_CLOSE_PENDING

FSCTL_OPLOCK_BREAK_ACK_NO_2

FSCTL_OPLOCK_BREAK_ACKNOWLEDGE

FSCTL_OPLOCK_BREAK_NOTIFY

FSCTL_REQUEST_BATCH_OPLOCK

FSCTL_REQUEST_FILTER_OPLOCK

FSCTL_REQUEST_OPLOCK_LEVEL_1

FSCTL_REQUEST_OPLOCK_LEVEL_2

FSCTL_SET_REPARSE_POINT

For more information about the system-defined FSCTL_XXX codes, see the Remarks section of the reference entry for DeviceIoControl in the Microsoft Windows SDK documentation.

Requirements

   
Target Platform Universal
Header fltkernel.h (include Fltkernel.h)
Library FltMgr.lib
DLL Fltmgr.sys
IRQL PASSIVE_LEVEL

See Also

FltDeviceIoControlFile

ZwFsControlFile