FLT_PARAMETERS for IRP_MJ_FAST_IO_CHECK_IF_POSSIBLE union

The following union component is used when the MajorFunction field of the FLT_IO_PARAMETER_BLOCK structure for the operation is IRP_MJ_FAST_IO_CHECK_IF_POSSIBLE.

Syntax


typedef union _FLT_PARAMETERS {
  ...    ;
  struct {
    LARGE_INTEGER             FileOffset;
    ULONG                     Length;
    ULONG POINTER_ALIGNMENT   LockKey;
    BOOLEAN POINTER_ALIGNMENT CheckForReadOperation;
  } FastIoCheckIfPossible;
  ...    ;
} FLT_PARAMETERS, *PFLT_PARAMETERS;

Members

FastIoCheckIfPossible

Structure containing the following members.

FileOffset

Starting byte offset within the cached file.

Length

Length, in bytes, of the data to be read or written.

LockKey

Key value associated with a byte-range lock on the target file. If the range to be read or written overlaps or is a subrange of a nonexclusively locked range within the file, this parameter must be the key for that shared lock. The shared lock must be held by the parent process of the calling thread; otherwise, this parameter is ignored.

CheckForReadOperation

Specifies whether this operation is to check for a read or write operation. It is set to TRUE for a read operation and FALSE for a write operation.

Remarks

The FLT_PARAMETERS structure for IRP_MJ_FAST_IO_CHECK_IF_POSSIBLE operations contains the parameters for a FastIoCheckIfPossible operation represented by a callback data (FLT_CALLBACK_DATA) structure. It is contained in an FLT_IO_PARAMETER_BLOCK structure.

IRP_MJ_FAST_IO_CHECK_IF_POSSIBLE is a fast I/O operation.

Requirements

Header

Fltkernel.h (include Fltkernel.h)

See also

FLT_CALLBACK_DATA
FLT_IO_PARAMETER_BLOCK
FLT_IS_FASTIO_OPERATION
FLT_IS_FS_FILTER_OPERATION
FLT_IS_IRP_OPERATION
FLT_PARAMETERS
FsRtlAreThereCurrentFileLocks
FsRtlCopyRead
FsRtlCopyWrite

 

 

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