kernel/drivers/gpu/drm/drm_prime.c, branch linux-4.16.y

drm/prime: skip CPU sync in map/unmap dma_buf

2017-12-04T16:30:19Z

Dma-bufs should already be device coherent, as they are only pulled in the CPU domain via the begin/end cpu_access calls. As we cache the mapping set up by dma_map_sg a CPU sync at this point will not actually guarantee proper coherency on non-coherent architectures, so we can as well stop pretending. This is an important performance fix for architectures which need explicit cache synchronization and userspace doing lots of dma-buf imports. Improves Weston on Etnaviv performance 5x, where before this patch > 90% of Weston CPU time was spent synchronizing caches for buffers which are already device coherent. Signed-off-by: Lucas Stach Reviewed-by: Chris Wilson Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20171130173428.8666-1-l.stach@pengutronix.de

drm/core: clean up references to drm_dev_unref()

2017-09-27T08:53:12Z

This is a continuation of a previous commit ("drm: introduce drm_dev_{get/put} functions") to replace all references to drm_dev_unref() in drm core files with drm_dev_put(). Signed-off-by: Aishwarya Pant Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20170926170400.GA7671@aishwarya

drm: introduce drm_dev_{get/put} functions

2017-09-26T11:12:15Z

Reference counting functions in the kernel typically use get/put suffixes. For maintaining coding style consistency, introduce drm_dev_{get/put} functions. All callers of drm_dev_ref() API have been converted in this patch and hence it has been dropped while the drm_dev_unref() API with non-trivial number of users remains for compatibility. The semantic patch scripts/coccinelle/api/drm-get-put.cocci has been updated with the new helper for conversion of drm_dev_unref() to drm_dev_put() Signed-off-by: Aishwarya Pant Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/6babda56134035a98220d5d37a4fd4048df214ce.1506413698.git.aishpant@gmail.com

drm/prime: Introduce drm_gem_prime_import_dev

2017-05-08T07:39:13Z

The existing drm_gem_prime_import function uses the underlying struct device of a drm_device for attaching to a dma_buf. Some drivers (notably vgem) may not have an underlying device structure. Offer an alternate function to attach using any available device structure. Signed-off-by: Laura Abbott Reviewed-by: Chris Wilson Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1493923548-20878-3-git-send-email-labbott@redhat.com

dma-buf: Rename dma-ops to prevent conflict with kunmap_atomic macro

2017-04-20T08:17:46Z

Seeing the kunmap_atomic dma_buf_ops share the same name with a macro in highmem.h, the former can be aliased if any dma-buf user includes that header. I'm personally trying to include highmem.h inside scatterlist.h and this breaks the dma-buf code proper. Christoph Hellwig suggested [1] renaming it and pushing this patch ASAP. To maintain consistency I've renamed all four of kmap* and kunmap* to be map* and unmap*. (Even though only kmap_atomic presently conflicts.) [1] https://www.spinics.net/lists/target-devel/msg15070.html Signed-off-by: Logan Gunthorpe Reviewed-by: Sinclair Yeh Acked-by: Daniel Vetter Acked-by: Sumit Semwal Signed-off-by: Sumit Semwal Link: http://patchwork.freedesktop.org/patch/msgid/1492630570-879-1-git-send-email-logang@deltatee.com

drm: Extract drm_prime.h

2017-03-09T15:18:02Z

Plus a little bit more documentation. v2: Untangle the missing forward decls to make drm_prime|gem.h free-standing. Reviewed-by: Gustavo Padovan Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/20170308141257.12119-3-daniel.vetter@ffwll.ch

drm: Introduce drm_gem_object_{get,put}()

2017-02-28T15:16:43Z

For consistency with other reference counting APIs in the kernel, add drm_gem_object_get() and drm_gem_object_put(), as well as an unlocked variant of the latter, to reference count GEM buffer objects. Compatibility aliases are added to keep existing code working. To help speed up the transition, all the instances of the old functions in the DRM core are already replaced in this commit. The existing semantic patch for the DRM subsystem-wide conversion is extended to account for these new helpers. Reviewed-by: Sean Paul Acked-by: Christian König Signed-off-by: Thierry Reding Link: http://patchwork.freedesktop.org/patch/msgid/20170228144643.5668-6-thierry.reding@gmail.com

drm/prime: Clarify DMA-BUF/GEM Object lifetime

2017-01-27T14:00:26Z

From the description of the "DMA-BUF/GEM Object references and lifetime overview" it is not clear when exactly dma_buf gets destroyed and memory freed: only driver .release function mentioned which makes confusion on the real buffer's lifetime. Add more description so all the paths are covered. Cc: Rob Clark Cc: Dave Airlie Cc: Daniel Vetter Signed-off-by: Oleksandr Andrushchenko [danvet: Minor spelling fixes, and some clarification of the 2nd paragraph.] Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1485500665-27690-1-git-send-email-andr2000@gmail.com

drm/gem|prime|mm: Use recommened kerneldoc for struct member refs

2017-01-25T15:20:21Z

I just learned that &struct_name.member_name works and looks pretty even. It doesn't (yet) link to the member directly though, which would be really good for big structures or vfunc tables (where the per-member kerneldoc tends to be long). Also some minor drive-by polish where it makes sense, I read a lot of docs ... Cc: Jani Nikula Cc: Chris Wilson Reviewed-by: Gustavo Padovan Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-5-daniel.vetter@ffwll.ch

drm: Take ownership of the dmabuf->obj when exporting

2016-12-08T09:29:22Z

Currently the reference for the dmabuf->obj is incremented for the dmabuf in drm_gem_prime_handle_to_fd() (at the high level userspace interface), but is released in drm_gem_dmabuf_release() (the lowlevel handler). Improve the symmetry of the dmabuf->obj ownership by acquiring the reference in drm_gem_dmabuf_export(). This makes it easier to use the prime functions directly. Signed-off-by: Chris Wilson [danvet: Update kerneldoc.] Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/20161207214527.22533-1-chris@chris-wilson.co.uk