FastIoMdlWriteComplete and FO_WRITE_THROUGH

Gentlefolk

It seems I observe that if FO_WRITE_THROUGH is set in FileObject->Flags then
FastIoMdlWriteComplete fails. I suppose this makes sense if we think that
since the cache is write-through the FastIo call which would update the
cache would also have to update the disk hence the system fails the FastIo
call in order to force the IRP path. I was wondering if contributors could
advise whether the supposition is correct, and whether this means as a
general rule FastIoMdlWriteComplete must fail if FO_WRITE_THROUGH.

Thanks in advance
Lyndon

Well no replies … but this does indeed seem to be the implementation of
FsRtlMdlWriteCompleteDev :slight_smile:

“Lyndon J Clarke” wrote in message
news:xxxxx@ntfsd…
> Gentlefolk
>
> It seems I observe that if FO_WRITE_THROUGH is set in FileObject->Flags
> then FastIoMdlWriteComplete fails. I suppose this makes sense if we think
> that since the cache is write-through the FastIo call which would update
> the cache would also have to update the disk hence the system fails the
> FastIo call in order to force the IRP path. I was wondering if
> contributors could advise whether the supposition is correct, and whether
> this means as a general rule FastIoMdlWriteComplete must fail if
> FO_WRITE_THROUGH.
>
> Thanks in advance
> Lyndon
>
>
>