Re: [PATCH v3 03/23] vfio: add per-region fd support

[John Levon <john.levon@nutanix.com>]

On Tue, Jun 10, 2025 at 11:58:18AM +0100, Mark Cave-Ayland wrote:

> > +        /* Use the per-region fd if set, or the shared fd. */
> > +        fd = region->vbasedev->region_fds ?
> > +             region->vbasedev->region_fds[region->nr] :
> > +             region->vbasedev->fd,
> > +
> 
> This feels a bit odd: if you're asking to map a VFIORegion then shouldn't
> that contain all the information required for the mapping, including the fd?
> 
> (goes and looks)
> 
> It appears that there is already a fd field in VFIORegion so is there a
> reason why we can't use this instead of adding region_fds to vbasedev?

region->fd was in earlier patchsets, but dropped as requested by Cédric. So we
must look it up here.

regards
john