FsRtlOplockIsFastIoPossible macro (rxprocs.h)

FsRtlOplockIsFastIoPossible checks a file's opportunistic lock (oplock) state to determine whether fast I/O can be performed on the file.

Syntax

void FsRtlOplockIsFastIoPossible(
   __a
);

__a

Opaque opportunistic lock pointer for the file. This pointer must have been initialized by a previous call to FsRtlInitializeOplock.

None

FsRtlOplockIsFastIoPossible determines whether fast I/O can be performed on a file, according to the following conditions:

If the Oplock parameter is NULL, or if the value of **Oplock* is NULL, there are no outstanding opportunistic locks on the file, and fast I/O can be performed on the file.
If an exclusive opportunistic lock was granted for the file, but no oplock break is in progress, fast I/O can be performed on the file.

For detailed information about opportunistic locks, see the Microsoft Windows SDK documentation.

Minifilters should call FltOplockIsFastIoPossible instead of FsRtlOplockIsFastIoPossible.