Re: [Xen-devel] [DRAFT v4] PV Calls protocol design document (former XenSock)

[Stefano Stabellini <stefano@xxxxxxxxxxx>]

On Wed, 3 Aug 2016, Wei Liu wrote:
> > # PV Calls Protocol
> > 
> > ## Rationale
> > 
> > PV Calls is a paravirtualized protocol for the POSIX socket API.
> > 
> > The purpose of PV Calls is to allow the implementation of a specific set
> > of POSIX functions to be done in a domain other than your own. It allows
> > connect, accept, bind, release, listen, poll, recvmsg and sendmsg to be
> > implemented in another domain.
> > 
> 
> The wording isn't really clear here. This design document as-is would
> inevitably make people start to compare PV Calls to various HV socks I'm
> afraid.

You are right, thanks for the feedback. I'll clarify it.


> Is PV Calls going to cover other stuff other than socket API? If it
> targets POSIX interfaces, maybe call it PV POSIX?
> 
> But then, if you extend the scope to cover POSIX APIs, I think you might
> want some discovery mechanism to see what APIs are paravirtualised?

Yes, it can potentially cover other interfaces -- I have a couple of
ideas in that area but I need to do some experiments first.

I fully agree that we need a discovery mechanism. What it is briefly
covered by this document, is that if a cmd is not supported by the
backend, ret is ENOTSUPP. But maybe we could also add a version node to
xenstore, that could be used to version the protocol supported by the
backend.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel