[Intel-gfx] [PATCH] drm/cma-helper: Return ENOENT for "no such gem obj"

[Daniel Vetter]

On Tue, Apr 18, 2017 at 10:40:21AM -0400, Sean Paul wrote:
> On Tue, Apr 18, 2017 at 03:29:29PM +0300, Laurent Pinchart wrote:
> > Hi Daniel,
> > 
> > Thank you for the patch.
> > 
> > On Tuesday 18 Apr 2017 14:11:20 Daniel Vetter wrote:
> > > All the error codes we (ab)use are strictly not the right ones (since
> > > they're all for the vfs, and the only thing we're allowed to do from
> > > an ioctl is EINVAL). But ENOENT is the common error code for failed to
> > > look up an object throughout drm, so let's use it in the cma helpers,
> > > too.
> > 
> > Regardless of which is best, it's true that ENOENT is used through the DRM 
> > code, so
> > 
> > Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > 
> > Someone should however mention that this changes the userspace API. I'll let 
> > you decide whether to ignore that comment :-)
> 
> Yeah, let's make sure we don't break any existing userspaces (a la pulseaudio).

Good point, but I think this is safe. I augmented the commit message and
merged the patch with Sean's irc r-b (plus Laurent's r-b from here).
-Daniel

> 
> Sean
> 
> > 
> > > Cc: Laurent Pinchart <Laurent.pinchart at ideasonboard.com>
> > > Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
> > > ---
> > >  drivers/gpu/drm/drm_fb_cma_helper.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c
> > > b/drivers/gpu/drm/drm_fb_cma_helper.c index d2b77b02830d..53f9bdf470d7
> > > 100644
> > > --- a/drivers/gpu/drm/drm_fb_cma_helper.c
> > > +++ b/drivers/gpu/drm/drm_fb_cma_helper.c
> > > @@ -189,7 +189,7 @@ struct drm_framebuffer
> > > *drm_fb_cma_create_with_funcs(struct drm_device *dev, obj =
> > > drm_gem_object_lookup(file_priv, mode_cmd->handles[i]);
> > >  		if (!obj) {
> > >  			dev_err(dev->dev, "Failed to lookup GEM object\n");
> > > -			ret = -ENXIO;
> > > +			ret = -ENOENT;
> > >  			goto err_gem_object_put;
> > >  		}
> > 
> > -- 
> > Regards,
> > 
> > Laurent Pinchart
> > 
> > _______________________________________________
> > dri-devel mailing list
> > dri-devel at lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/dri-devel
> 
> -- 
> Sean Paul, Software Engineer, Google / Chromium OS

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch