On 10/18/22 14:34, Christian König wrote: > 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 König, 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 König. >>> >>> - 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 König. >>> >>> - Corrected and factored out dma-buf locking documentation into >>> a separate patch, like was suggested by Christian König. >>> >>> - 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 König. 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 König. >>> >>> - 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-next > > Finally! 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. I'll ping you if anything will show up. Thank you! -- Best regards, Dmitry
