Re: [Qemu-devel] vhost-user: broken mem regions

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Jun 25, 2014 at 02:57:52PM +0000, Damjan Marion (damarion) wrote:
> 
> On 25 Jun 2014, at 16:27, Michael S. Tsirkin <mst@redhat.com> wrote:
> 
> > On Wed, Jun 25, 2014 at 02:20:56PM +0000, Damjan Marion (damarion) wrote:
> >> 
> >> On 25 Jun 2014, at 16:13, Nikolay Nikolaev <n.nikolaev@virtualopensystems.com> wrote:
> >> 
> >>>>> - it will require changes on the user side also
> >>>> 
> >>>> why would it?
> >>>> format seems unchanged, right?
> >>> 
> >>> yes, but it will happen that multiple regions have same FD so call to mmap()
> >>> should look different, I’m still playing with this on user side...
> >>> but then you shoudl somehow accumulate the sizes and send just a single fd, something along these lines. 
> >> 
> >> Yes, so I’m not very happy with that approach and looking if there is better proposal, 
> >> or at least wider agreement how to address this issue.
> >> 
> >> Damjan
> > 
> > still not sure what the issue is ...
> > 
> 
> No issue, just additional logic is needed on user side to calculate total size of shared regions and call mmap() once per FD.
> 
> Agree?

why not just call it multiple times? AFAIK linux handles this just fine.

> If this is the way to go I will submit patch when I get it tested..
> 
> Damjan
> 
>