Re: [Xen-devel] [PATCH 2/7] ioreq: add internal ioreq initialization support

[Paul Durrant <Paul.Durrant@citrix.com>]

> -----Original Message-----
> From: Roger Pau Monne <roger.pau@citrix.com>
> Sent: 22 August 2019 08:24
> To: Paul Durrant <Paul.Durrant@citrix.com>
> Cc: xen-devel@lists.xenproject.org; Jan Beulich <jbeulich@suse.com>; Andrew Cooper
> <Andrew.Cooper3@citrix.com>; Wei Liu <wl@xen.org>
> Subject: Re: [PATCH 2/7] ioreq: add internal ioreq initialization support
> 
> On Wed, Aug 21, 2019 at 06:24:17PM +0200, Paul Durrant wrote:
> > > -----Original Message-----
> > > From: Roger Pau Monne <roger.pau@citrix.com>
> > > Sent: 21 August 2019 15:59
> > > To: xen-devel@lists.xenproject.org
> > > Cc: Roger Pau Monne <roger.pau@citrix.com>; Jan Beulich <jbeulich@suse.com>; Andrew Cooper
> > > <Andrew.Cooper3@citrix.com>; Wei Liu <wl@xen.org>; Paul Durrant <Paul.Durrant@citrix.com>
> > > Subject: [PATCH 2/7] ioreq: add internal ioreq initialization support
> > >
> > > Add support for internal ioreq servers to initialization and
> > > deinitialization routines, prevent some functions from being executed
> > > against internal ioreq servers and add guards to only allow internal
> > > callers to modify internal ioreq servers. External callers (ie: from
> > > hypercalls) are only allowed to deal with external ioreq servers.
> >
> > It's kind of ugly to have the extra 'internal' argument passed to anything other than the create
> function so I wonder whether it would be neater to encode it in the ioreq server id. I.e. we have
> distinct id ranges for internal and external servers. What do you think?
> 
> That would be fine, I guess I could use the most significant bit in
> the id to signal whether the server is internal or external, and
> reject dmop calls that target internal servers based on the provided
> id. Does that sound sensible?
> 

Yes, that's basically what I was thinking initially although, as you observe, in the thread for patch #3 having two smaller consecutive ranges would be more convenient.

  Paul

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel