FLT_PARAMETERS for IRP_MJ_DIRECTORY_CONTROL union
Union component used when the MajorFunction field of the FLT_IO_PARAMETER_BLOCK structure for the operation is IRP_MJ_DIRECTORY_CONTROL.
Syntax
typedef union _FLT_PARAMETERS {
... ;
union {
struct {
ULONG Length;
PUNICODE_STRING FileName;
FILE_INFORMATION_CLASS FileInformationClass;
ULONG POINTER_ALIGNMENT FileIndex;
PVOID DirectoryBuffer;
PMDL MdlAddress;
} QueryDirectory;
struct {
ULONG Length;
ULONG POINTER_ALIGNMENT CompletionFilter;
ULONG Spare1;
ULONG POINTER_ALIGNMENT Spare2;
PVOID DirectoryBuffer;
PMDL MdlAddress;
} NotifyDirectory;
} DirectoryControl;
... ;
} FLT_PARAMETERS, *PFLT_PARAMETERS;
Members
DirectoryControl: Structure containing the following members.
QueryDirectory: Union component used for IRP_MN_QUERY_DIRECTORY operations.
Length: Length, in bytes, of the buffer that the QueryDirectory.DirectoryBuffer member points to.
FileName: Pointer to a UNICODE_STRING structure that contains the name of a file within the specified directory.
FileInformationClass: Specifies one of the values described below.
Value Meaning FileBothDirectoryInformation Return a FILE_BOTH_DIR_INFORMATION structure for each file. FileDirectoryInformation Return a FILE_DIRECTORY_INFORMATION structure for each file. FileFullDirectoryInformation Return a FILE_FULL_DIR_INFORMATION structure for each file. FileIdBothDirectoryInformation Return a FILE_ID_BOTH_DIR_INFORMATION structure for each file. FileIdFullDirectoryInformation Return a FILE_ID_FULL_DIR_INFORMATION structure for each file. FileNamesInformation Return a FILE_NAMES_INFORMATION structure for each file. FileObjectIdInformation Return a FILE_OBJECTID_INFORMATION structure for each file. FileReparsePointInformation Return a single FILE_REPARSE_POINT_INFORMATION structure for the directory. FileIndex: Index of the file where the directory scan begins. Ignored if the SL_INDEX_SPECIFIED flag is not set. This parameter cannot be specified in any Win32 function or kernel-mode support routine. Currently it is used only by the NT virtual DOS machine (NTVDM), which exists only on 32-bit NT-based operating systems. Note that the file index is undefined for file systems, such as NTFS, in which the position of a file within the parent directory is not fixed and can be changed at any time to maintain sort order.
DirectoryBuffer: Pointer to a caller-supplied output buffer that receives the requested information about the contents of the directory. This member is optional and can be NULL if a MDL is provided in QueryDirectory.MdlAddress. See Remarks.
MdlAddress: Address of a memory descriptor list (MDL) that describes the buffer that the QueryDirectory.DirectoryBuffer member points to. This member is optional and can be NULL if a buffer is provided in QueryDirectory.DirectoryBuffer. See Remarks.
NotifyDirectory: Union component used for IRP_MN_NOTIFY_CHANGE_DIRECTORY operations.
Length: Length, in bytes, of the buffer that the NotifyDirectory.DirectoryBuffer member points to.
CompletionFilter: Bitmask of flags that specify the types of changes to files or directories that should cause the IRPs in the notify list to be completed. The possible flag values are described following.
Flag Meaning FILE_NOTIFY_CHANGE_FILE_NAME A file has been added, deleted, or renamed in this directory. FILE_NOTIFY_CHANGE_DIR_NAME A subdirectory has been created, removed, or renamed. FILE_NOTIFY_CHANGE_NAME This directory's name has changed. FILE_NOTIFY_CHANGE_ATTRIBUTES The value of an attribute of this file, such as last access time, has changed. FILE_NOTIFY_CHANGE_SIZE This file's size has changed. FILE_NOTIFY_CHANGE_LAST_WRITE This file's last modification time has changed. FILE_NOTIFY_CHANGE_LAST_ACCESS This file's last access time has changed. FILE_NOTIFY_CHANGE_CREATION This file's creation time has changed. FILE_NOTIFY_CHANGE_EA This file's extended attributes have been modified. FILE_NOTIFY_CHANGE_SECURITY This file's security information has changed. FILE_NOTIFY_CHANGE_STREAM_NAME A file stream has been added, deleted, or renamed in this directory. FILE_NOTIFY_CHANGE_STREAM_SIZE This file stream's size has changed. FILE_NOTIFY_CHANGE_STREAM_WRITE This file stream's data has changed. Spare1: Not currently used.
Spare2: Not currently used.
DirectoryBuffer: Pointer to a caller-supplied output buffer that receives the requested information about the contents of the directory. This member is optional and can be NULL if a MDL is provided in NotifyDirectory.MdlAddress. See Remarks.
MdlAddress: Address of an MDL that describes the buffer that the NotifyDirectory.DirectoryBuffer member points to. This member is optional and can be NULL if a buffer is provided in NotifyDirectory.DirectoryBuffer. See Remarks.
Remarks
The FLT_PARAMETERS structure for IRP_MJ_DIRECTORY_CONTROL operations contains the parameters for an IRP-based directory-control-information operation represented by a callback data (FLT_CALLBACK_DATA) structure. It is contained in an FLT_IO_PARAMETER_BLOCK structure.
If both a DirectoryBuffer and MdlAddress buffer are provided, it is recommended that minifilters use the MDL. The memory that DirectoryBuffer points to is valid when it is a user mode address being accessed within the context of the calling process, or if it is a kernel mode address.
If a minifilter changes the value of MdlAddress, then after its post operation callback, Filter Manager will free the MDL currently stored in MdlAddress and restore the previous value of MdlAddress.
IRP_MJ_DIRECTORY_CONTROL is an IRP-based operation.
Requirements
| Requirement type | Requirement |
|---|---|
| Header | Fltkernel.h (include Fltkernel.h) |
See also
FILE_REPARSE_POINT_INFORMATION
FltNotifyFilterChangeDirectory
FsRtlNotifyFilterChangeDirectory