Christian König
2022-Oct-18 11:34 UTC
[PATCH v7 00/21] Move all drivers to a common dma-buf locking convention
Am 18.10.22 um 01:07 schrieb Dmitry Osipenko:> On 10/17/22 20:22, Dmitry Osipenko wrote: >> Hello, >> >> This series moves all drivers to a dynamic dma-buf locking specification. >> From now on all dma-buf importers are made responsible for holding >> dma-buf's reservation lock around all operations performed over dma-bufs >> in accordance to the locking specification. This allows us to utilize >> reservation lock more broadly around kernel without fearing of a potential >> deadlocks. >> >> This patchset passes all i915 selftests. It was also tested using VirtIO, >> Panfrost, Lima, Tegra, udmabuf, AMDGPU and Nouveau drivers. I tested cases >> of display+GPU, display+V4L and GPU+V4L dma-buf sharing (where appropriate), >> which covers majority of kernel drivers since rest of the drivers share >> same or similar code paths. >> >> Changelog: >> >> v7: - Rebased on top of recent drm-misc-next. >> >> - Added ack from Jason Gunthorpe to the RDMA patch. >> >> - Added iosys_map_clear() to dma_buf_vmap_unlocked(), making it fully >> consistent with dma_buf_vmap(). >> >> v6: - Added r-b from Michael Ruhl to the i915 patch. >> >> - Added acks from Sumit Semwal and updated commit message of the >> "Move dma_buf_vmap() to dynamic locking specification" patch like >> was suggested by Sumit. >> >> - Added "!dmabuf" check to dma_buf_vmap_unlocked() to match the locked >> variant of the function, for consistency. >> >> v5: - Added acks and r-bs that were given to v4. >> >> - Changed i915 preparation patch like was suggested by Michael Ruhl. >> The scope of reservation locking is smaller now. >> >> v4: - Added dma_buf_mmap() to the "locking convention" documentation, >> which was missed by accident in v3. >> >> - Added acks from Christian K?nig, Tomasz Figa and Hans Verkuil that >> they gave to couple v3 patches. >> >> - Dropped the "_unlocked" postfix from function names that don't have >> the locked variant, as was requested by Christian K?nig. >> >> - Factored out the per-driver preparations into separate patches >> to ease reviewing of the changes, which is now doable without the >> global dma-buf functions renaming. >> >> - Factored out the dynamic locking convention enforcements into separate >> patches which add the final dma_resv_assert_held(dmabuf->resv) to the >> dma-buf API functions. >> >> v3: - Factored out dma_buf_mmap_unlocked() and attachment functions >> into aseparate patches, like was suggested by Christian K?nig. >> >> - Corrected and factored out dma-buf locking documentation into >> a separate patch, like was suggested by Christian K?nig. >> >> - Intel driver dropped the reservation locking fews days ago from >> its BO-release code path, but we need that locking for the imported >> GEMs because in the end that code path unmaps the imported GEM. >> So I added back the locking needed by the imported GEMs, updating >> the "dma-buf attachment locking specification" patch appropriately. >> >> - Tested Nouveau+Intel dma-buf import/export combo. >> >> - Tested udmabuf import to i915/Nouveau/AMDGPU. >> >> - Fixed few places in Etnaviv, Panfrost and Lima drivers that I missed >> to switch to locked dma-buf vmapping in the drm/gem: Take reservation >> lock for vmap/vunmap operations" patch. In a result invalidated the >> Christian's r-b that he gave to v2. >> >> - Added locked dma-buf vmap/vunmap functions that are needed for fixing >> vmappping of Etnaviv, Panfrost and Lima drivers mentioned above. >> I actually had this change stashed for the drm-shmem shrinker patchset, >> but then realized that it's already needed by the dma-buf patches. >> Also improved my tests to better cover these code paths. >> >> v2: - Changed locking specification to avoid problems with a cross-driver >> ww locking, like was suggested by Christian K?nig. Now the attach/detach >> callbacks are invoked without the held lock and exporter should take the >> lock. >> >> - Added "locking convention" documentation that explains which dma-buf >> functions and callbacks are locked/unlocked for importers and exporters, >> which was requested by Christian K?nig. >> >> - Added ack from Tomasz Figa to the V4L patches that he gave to v1. >> >> Dmitry Osipenko (21): >> dma-buf: Add unlocked variant of vmapping functions >> dma-buf: Add unlocked variant of attachment-mapping functions >> drm/gem: Take reservation lock for vmap/vunmap operations >> drm/prime: Prepare to dynamic dma-buf locking specification >> drm/armada: Prepare to dynamic dma-buf locking specification >> drm/i915: Prepare to dynamic dma-buf locking specification >> drm/omapdrm: Prepare to dynamic dma-buf locking specification >> drm/tegra: Prepare to dynamic dma-buf locking specification >> drm/etnaviv: Prepare to dynamic dma-buf locking specification >> RDMA/umem: Prepare to dynamic dma-buf locking specification >> misc: fastrpc: Prepare to dynamic dma-buf locking specification >> xen/gntdev: Prepare to dynamic dma-buf locking specification >> media: videobuf2: Prepare to dynamic dma-buf locking specification >> media: tegra-vde: Prepare to dynamic dma-buf locking specification >> dma-buf: Move dma_buf_vmap() to dynamic locking specification >> dma-buf: Move dma_buf_attach() to dynamic locking specification >> dma-buf: Move dma_buf_map_attachment() to dynamic locking >> specification >> dma-buf: Move dma_buf_mmap() to dynamic locking specification >> dma-buf: Document dynamic locking convention >> media: videobuf2: Stop using internal dma-buf lock >> dma-buf: Remove obsoleted internal lock >> >> Documentation/driver-api/dma-buf.rst | 6 + >> drivers/dma-buf/dma-buf.c | 216 +++++++++++++++--- >> drivers/gpu/drm/armada/armada_gem.c | 8 +- >> drivers/gpu/drm/drm_client.c | 4 +- >> drivers/gpu/drm/drm_gem.c | 24 ++ >> drivers/gpu/drm/drm_gem_dma_helper.c | 6 +- >> drivers/gpu/drm/drm_gem_framebuffer_helper.c | 6 +- >> drivers/gpu/drm/drm_gem_ttm_helper.c | 9 +- >> drivers/gpu/drm/drm_prime.c | 6 +- >> drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c | 2 +- >> drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c | 2 +- >> drivers/gpu/drm/i915/gem/i915_gem_object.c | 14 ++ >> .../drm/i915/gem/selftests/i915_gem_dmabuf.c | 16 +- >> drivers/gpu/drm/lima/lima_sched.c | 4 +- >> drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c | 4 +- >> drivers/gpu/drm/panfrost/panfrost_dump.c | 4 +- >> drivers/gpu/drm/panfrost/panfrost_perfcnt.c | 6 +- >> drivers/gpu/drm/qxl/qxl_object.c | 17 +- >> drivers/gpu/drm/qxl/qxl_prime.c | 4 +- >> drivers/gpu/drm/tegra/gem.c | 17 +- >> drivers/infiniband/core/umem_dmabuf.c | 7 +- >> .../common/videobuf2/videobuf2-dma-contig.c | 22 +- >> .../media/common/videobuf2/videobuf2-dma-sg.c | 19 +- >> .../common/videobuf2/videobuf2-vmalloc.c | 17 +- >> .../platform/nvidia/tegra-vde/dmabuf-cache.c | 6 +- >> drivers/misc/fastrpc.c | 6 +- >> drivers/xen/gntdev-dmabuf.c | 8 +- >> include/drm/drm_gem.h | 3 + >> include/linux/dma-buf.h | 17 +- >> 29 files changed, 325 insertions(+), 155 deletions(-) >> > Applied to drm-misc-nextFinally! Fingers crossed that all corner cases where fixed during the review. But if anything shows up feel free to loop me in to help fixing things. Thanks a lot for doing this, Christian.