Re: [PATCH RESEND] virtio-pmem: PMEM device spec

[Cornelia Huck <cohuck@redhat.com>]

On Fri, Jul 30 2021, Pankaj Gupta <pankaj.gupta.linux@gmail.com> wrote:

>> > +Also, configures a flush callback function with the corresponding region.
>>
>> Not sure if that is too specific already... maybe something like "Also,
>> it configures a notification for when the corresponding region is flushed."?
>
> Maybe will remove this line altogether as it is implementation
> details?

Maybe... I think the point is to configure _something_, not sure if we
can really generalize that. Other ideas welcome.

>> See above for "flush callback". I'm mostly worrying about the wording
>> being generic enough (even though it's probably obvious enough for
>> non-Linux people as well.)
>
> yes, Something below is better?
>
> The driver MUST not enable any explicit FLUSH on the file memory
> mapped from the Virtio pmem device

Hm, not sure. Would like to see feedback from others that had worked in
this area.

>
>>
>> > +
>> > +\subsection{Driver Operations}\label{sec:Device Types / PMEM Driver / Driver Operation}
>> > +\drivernormative{\subsubsection}{Driver Operation: Virtqueue command}{Device Types / PMEM Driver / Driver Operation / Virtqueue command}
>> > +
>> > +Driver MUST send VIRTIO_FLUSH command on request virtqueue, allows guest userspace process to perform IO operations asynchronously.
>>
>> s/Driver/The driver/
>>
>> I don't think we should refer to "guest userspace" in the spec; can we
>> reword this?
>
> Sure
>
> Driver MUST send VIRTIO_FLUSH command on request virtqueue, thus
> allows asynchronous FLUSH operation on the files present in Virtio
> pmem device.

s/Driver/The driver/
s/allows/allowing/

I'm not sure whether we should refer to 'files'.

Again, feedback from others welcome; this is not really one of my core topics.

>
>>
>> > +
>> > +Driver SHOULD handle multiple fsync requests on files present on the device.
>>
>> s/Driver/The driver/
>
> o.k
>
>>
>> Again, a bit unsure on whether this is generic enough.
>
> Driver SHOULD handle multiple FLUSH requests on the files present on
> the Virtio pmem device.

Same here. I'm afraid this is not easy :(