[Intel-gfx] [PATCH v1 1/5] iommufd: Create access in vfio_iommufd_emulated_bind()

[Tian, Kevin]

> From: Nicolin Chen
> Sent: Wednesday, March 15, 2023 2:51 AM
> 
> On Fri, Mar 10, 2023 at 02:08:15AM +0000, Tian, Kevin wrote:
> > External email: Use caution opening links or attachments
> >
> >
> > > From: Liu, Yi L <yi.l.liu at intel.com>
> > > Sent: Wednesday, March 8, 2023 9:14 PM
> > >
> > > @@ -449,33 +450,18 @@ iommufd_access_create(struct iommufd_ctx
> *ictx,
> > > u32 ioas_id,
> > >       access->data = data;
> > >       access->ops = ops;
> > >
> > > -     obj = iommufd_get_object(ictx, ioas_id, IOMMUFD_OBJ_IOAS);
> > > -     if (IS_ERR(obj)) {
> > > -             rc = PTR_ERR(obj);
> > > -             goto out_abort;
> > > -     }
> > > -     access->ioas = container_of(obj, struct iommufd_ioas, obj);
> > > -     iommufd_ref_to_users(obj);
> > > -
> > >       if (ops->needs_pin_pages)
> > >               access->iova_alignment = PAGE_SIZE;
> > >       else
> > >               access->iova_alignment = 1;
> > > -     rc = iopt_add_access(&access->ioas->iopt, access);
> > > -     if (rc)
> > > -             goto out_put_ioas;
> > >
> > >       /* The calling driver is a user until iommufd_access_destroy() */
> > >       refcount_inc(&access->obj.users);
> > > +     mutex_init(&access->ioas_lock);
> > >       access->ictx = ictx;
> > >       iommufd_ctx_get(ictx);
> >
> > this refcnt get should be moved to the start given next patch
> > removes the reference in the caller side.
> 
> I don't feel quite convincing to justify for moving it in this
> patch. Perhaps we should do that in the following patch, where
> it needs this? Or another individual patch moving this alone?
> 

Next patch. I just tried to point out the required change caused
by next patch. 😊