On 12/11/14 09:41, Benjamin Gaignard wrote: > The same kind of issue has been fixed in v4l2: > > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/patch/drivers/media/v4l2-core/videobuf2-core.c?id=c1b96a236e94d49d9396d0bbceb5524519c5c66e > > I'm ok to add a DRM_RDWR flag, just do not remove the code from sti > driver until I have been able to test it. Don't worry. I'll do that as a separate patch so you can ack/nack as you need to. Daniel. > > Benjamin > > > 2014-11-11 17:26 GMT+01:00 Rob Clark <robdclark@xxxxxxxxx>: >> On Tue, Nov 11, 2014 at 9:28 AM, Daniel Thompson >> <daniel.thompson@xxxxxxxxxx> wrote: >>> On 10/11/14 17:36, Rob Clark wrote: >>>> On Mon, Nov 10, 2014 at 12:16 PM, Daniel Thompson >>>> <daniel.thompson@xxxxxxxxxx> wrote: >>>>> diff --git a/drivers/gpu/drm/msm/msm_gem_prime.c b/drivers/gpu/drm/msm/msm_gem_prime.c >>>>> index ad772fe36115..4e4fa5828d5d 100644 >>>>> --- a/drivers/gpu/drm/msm/msm_gem_prime.c >>>>> +++ b/drivers/gpu/drm/msm/msm_gem_prime.c >>>>> @@ -20,6 +20,14 @@ >>>>> >>>>> #include <linux/dma-buf.h> >>>>> >>>>> +struct dma_buf *msm_gem_prime_export(struct drm_device *dev, >>>>> + struct drm_gem_object *obj, int flags) >>>>> +{ >>>>> + /* we want to be able to write in mmapped buffer */ >>>>> + flags |= O_RDWR; >>>>> + return drm_gem_prime_export(dev, obj, flags); >>>>> +} >>>>> + >>>> >>>> seems like this probably should be done more centrally.. and in fact, >>>> might be better to have something like this in >>>> drm_prime_handle_to_fd_ioctl: >>>> >>>> /* check flags are valid */ >>>> - if (args->flags & ~DRM_CLOEXEC) >>>> + if (args->flags & ~(DRM_CLOEXEC | O_RDWR)) >>>> return -EINVAL; >>>> >>>> so exporter can specify whether to allow mmap or not. >>> >>> That makes sense I'll try this. >>> >>> Do we need to wrap O_RDWR in the same way we wrap O_CLOEXEC? (I don't >>> really understand why DRM_CLOEXEC exists; even the patch description >>> from when the symbol was introduced names it O_CLOEXEC). >> >> I *think* wrapping it w/ DRM_CLOEXEC was mostly just for purposes of >> making it clear which flags are appropriate.. probably best to do the >> same w/ a DRM_RDWR I guess >> >> BR, >> -R >> >>> Also the "flags |= O_RDWR" approach is copied from the sti driver. I'll >>> share a patch to remove it but that will definitely needs Benjamin's ack >>> because it will stop some userspaces working correctly (however I >>> suspect that Benjamin may be the only person currently with such a >>> userspace and that he can be persuaded not to call it a regression). >>> >>> >>> Daniel. > > > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
