On Wed, May 04, 2022 at 07:58:38AM -0600, Jeffrey Hugo wrote: > On 5/4/2022 3:38 AM, Daniel Vetter wrote: > > On Mon, May 02, 2022 at 06:41:39PM +0300, Jani Nikula wrote: > > > On Fri, 29 Apr 2022, Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx> wrote: > > > > DEFINE_DRM_GEM_FOPS() references drm functions from other headers. For > > > > example drm_open() is defined in drm_file.h and drm_ioctl() is defined > > > > in drm_ioctl.h. Since drm_gem.h doesn't include these headers, it > > > > relies on an implicit include from the .c file to have included these > > > > required headers before DEFINE_DRM_GEM_FOPS() gets used. Relying on > > > > these implicit includes can cause build failures for new code that > > > > doesn't know about these requirements, and can lead to future problems > > > > if the headers ever get restructured as there will be a need to update > > > > every downstream file that includes drm_gem.h. > > > > > > > > Lets fix this explicitly including the required headers in drm_gem.h so > > > > that code that includes drm_gem.h does not need to worry about these > > > > implicit dependencies. > > > > > > In the general case, I tend to agree, but in this specific instance I > > > think I'd err on the side of fewer includes. I think the more likely > > > outcome here is accumulating implicit dependencies on symbols from > > > drm_file.h and drm_ioctl.h by including drm_gem.h only! > > > > > > I do think headers need to be self-contained, and we actually enforce > > > this in i915 (see HDRTEST in drivers/gpu/drm/i915/Makefile), but not to > > > the point of macro expansions. > > > > Yeah we abuse macros in a bunch of places to untangle header dependencies, > > so then going back and pulling in all the headers back in feels a bit > > silly and defeats the point. > > Fair enough. I'll consider this NAK'd > > I've been pondering alternate solutions, but haven't come up with any. I > guess, for now, the status quo will remain. I think a standalone header for gem fops or so might be an option. We also have some macro iirc for standard stuff in drm_driver (or at least had in the past, maybe that's cleaned up now better). That would allow drivers to include this monster header that pulls in a lot of things in the one place they define their file ops, and nowhere else. I think that would cover everything we'd want to achieve? But would be a bit of churn to roll out everywhere. -Daniel > > > > > iow, I concur. > > -Daniel > > > > > > > > BR, > > > Jani. > > > > > > > > > > > > > > > > > Signed-off-by: Jeffrey Hugo <quic_jhugo@xxxxxxxxxxx> > > > > --- > > > > include/drm/drm_gem.h | 2 ++ > > > > 1 file changed, 2 insertions(+) > > > > > > > > diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h > > > > index 9d7c61a..1cbe3d8 100644 > > > > --- a/include/drm/drm_gem.h > > > > +++ b/include/drm/drm_gem.h > > > > @@ -37,6 +37,8 @@ > > > > #include <linux/kref.h> > > > > #include <linux/dma-resv.h> > > > > +#include <drm/drm_file.h> > > > > +#include <drm/drm_ioctl.h> > > > > #include <drm/drm_vma_manager.h> > > > > struct iosys_map; > > > > > > -- > > > Jani Nikula, Intel Open Source Graphics Center > > > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch
