Hook-up drm_gem_dmabuf_{begin,end}_cpu_access() to drm_gem_sync() so
that drivers relying on the default prime_dmabuf_ops can still have
a way to prepare for CPU accesses from outside the UMD.v2: - New commit v3: - Don't return an error on NOP syncs, and document that case in a comment Signed-off-by: Boris Brezillon <[email protected]> --- drivers/gpu/drm/drm_prime.c | 42 +++++++++++++++++++++++++++++++++++++ include/drm/drm_prime.h | 5 +++++ 2 files changed, 47 insertions(+) diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index 43a10b4af43a..30d495c70afb 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -823,6 +823,46 @@ int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma) } EXPORT_SYMBOL(drm_gem_dmabuf_mmap); +int drm_gem_dmabuf_begin_cpu_access(struct dma_buf *dma_buf, + enum dma_data_direction direction) +{ + struct drm_gem_object *obj = dma_buf->priv; + enum drm_gem_object_access_flags access = DRM_GEM_OBJECT_CPU_ACCESS; + + /* begin_cpu_access(DMA_TO_DEVICE) is a NOP, the sync will happen + * in the end_cpu_access() path. + */ + if (direction == DMA_FROM_DEVICE) + access |= DRM_GEM_OBJECT_READ_ACCESS; + else if (direction == DMA_BIDIRECTIONAL) + access |= DRM_GEM_OBJECT_RW_ACCESS; + else + return 0; + + return drm_gem_sync(obj, 0, obj->size, access); +} +EXPORT_SYMBOL(drm_gem_dmabuf_begin_cpu_access); + +int drm_gem_dmabuf_end_cpu_access(struct dma_buf *dma_buf, + enum dma_data_direction direction) +{ + struct drm_gem_object *obj = dma_buf->priv; + enum drm_gem_object_access_flags access = DRM_GEM_OBJECT_DEV_ACCESS; + + /* end_cpu_access(DMA_FROM_DEVICE) is a NOP, the sync should have + * happened in the begin_cpu_access() path already. + */ + if (direction == DMA_TO_DEVICE) + access |= DRM_GEM_OBJECT_READ_ACCESS; + else if (direction == DMA_BIDIRECTIONAL) + access |= DRM_GEM_OBJECT_RW_ACCESS; + else + return 0; + + return drm_gem_sync(obj, 0, obj->size, access); +} +EXPORT_SYMBOL(drm_gem_dmabuf_end_cpu_access); + static const struct dma_buf_ops drm_gem_prime_dmabuf_ops = { .attach = drm_gem_map_attach, .detach = drm_gem_map_detach, @@ -832,6 +872,8 @@ static const struct dma_buf_ops drm_gem_prime_dmabuf_ops = { .mmap = drm_gem_dmabuf_mmap, .vmap = drm_gem_dmabuf_vmap, .vunmap = drm_gem_dmabuf_vunmap, + .begin_cpu_access = drm_gem_dmabuf_begin_cpu_access, + .end_cpu_access = drm_gem_dmabuf_end_cpu_access, }; /** diff --git a/include/drm/drm_prime.h b/include/drm/drm_prime.h index f50f862f0d8b..052fba039bb6 100644 --- a/include/drm/drm_prime.h +++ b/include/drm/drm_prime.h @@ -92,6 +92,11 @@ void drm_gem_dmabuf_vunmap(struct dma_buf *dma_buf, struct iosys_map *map); int drm_gem_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma); int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma); +int drm_gem_dmabuf_begin_cpu_access(struct dma_buf *dma_buf, + enum dma_data_direction direction); +int drm_gem_dmabuf_end_cpu_access(struct dma_buf *dma_buf, + enum dma_data_direction direction); + struct sg_table *drm_prime_pages_to_sg(struct drm_device *dev, struct page **pages, unsigned int nr_pages); struct dma_buf *drm_gem_prime_export(struct drm_gem_object *obj, -- 2.51.0
