Pin and unpin the DMA-buf exported BOs only on demand and invalidate all DMA-buf mappings when the underlying BO moves.
Signed-off-by: Christian König christian.koenig@amd.com --- drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 5 ++ drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c | 73 ++++++++++++++++++++-- 2 files changed, 72 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c index ec9e45004bff..fdb98eb562db 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c @@ -31,6 +31,7 @@ */ #include <linux/list.h> #include <linux/slab.h> +#include <linux/dma-buf.h> #include <drm/drmP.h> #include <drm/amdgpu_drm.h> #include <drm/drm_cache.h> @@ -1192,6 +1193,10 @@ void amdgpu_bo_move_notify(struct ttm_buffer_object *bo,
amdgpu_bo_kunmap(abo);
+ if (abo->gem_base.dma_buf && !abo->gem_base.import_attach && + bo->mem.mem_type != TTM_PL_SYSTEM) + dma_buf_invalidate_mappings(abo->gem_base.dma_buf); + /* remember the eviction */ if (evict) atomic64_inc(&adev->num_evictions); diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c index 56e2a606b9a1..40cd89271b20 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c @@ -209,6 +209,61 @@ __reservation_object_make_exclusive(struct reservation_object *obj) return -ENOMEM; }
+/** + * amdgpu_gem_pin_dma_buf - &dma_buf_ops.pin_dma_buf implementation + * + * @dma_buf: DMA-buf to pin in memory + * + * Pin the BO which is backing the DMA-buf so that it can't move any more. + */ +static int amdgpu_gem_pin_dma_buf(struct dma_buf *dma_buf) +{ + struct drm_gem_object *obj = dma_buf->priv; + struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); + + /* pin buffer into GTT */ + return amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT); +} + +/** + * amdgpu_gem_unpin_dma_buf - &dma_buf_ops.unpin_dma_buf implementation + * + * @dma_buf: DMA-buf to unpin + * + * Unpin a previously pinned BO to make it movable again. + */ +static void amdgpu_gem_unpin_dma_buf(struct dma_buf *dma_buf) +{ + struct drm_gem_object *obj = dma_buf->priv; + struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); + + amdgpu_bo_unpin(bo); +} + +/** + * amdgpu_gem_dma_buf_attach - &dma_buf_ops.attach implementation + * + * @dma_buf: DMA-buf we attach to + * @attach: DMA-buf attachment + * + * Returns: + * Always zero for success. + */ +static int amdgpu_gem_dma_buf_attach(struct dma_buf *dma_buf, + struct dma_buf_attachment *attach) +{ + struct drm_gem_object *obj = dma_buf->priv; + struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); + + /* Make sure the buffer is pinned when userspace didn't set GTT as + * preferred domain. This avoid ping/pong situations with scan out BOs. + */ + if (!(bo->preferred_domains & AMDGPU_GEM_DOMAIN_GTT)) + attach->invalidate = NULL; + + return 0; +} + /** * amdgpu_gem_map_dma_buf - &dma_buf_ops.map_dma_buf implementation * @attach: DMA-buf attachment @@ -247,10 +302,15 @@ amdgpu_gem_map_dma_buf(struct dma_buf_attachment *attach, return ERR_PTR(r); }
- /* pin buffer into GTT */ - r = amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT); - if (r) - return ERR_PTR(r); + if (attach->invalidate) { + /* move buffer into GTT */ + struct ttm_operation_ctx ctx = { false, false }; + + amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_GTT); + r = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx); + if (r) + return ERR_PTR(r); + }
sgt = drm_prime_pages_to_sg(bo->tbo.ttm->pages, bo->tbo.num_pages); if (IS_ERR(sgt)) @@ -289,8 +349,6 @@ static void amdgpu_gem_unmap_dma_buf(struct dma_buf_attachment *attach, struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj); struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
- amdgpu_bo_unpin(bo); - if (attach->dev->driver != adev->dev->driver && bo->prime_shared_count) bo->prime_shared_count--;
@@ -357,6 +415,9 @@ static int amdgpu_gem_begin_cpu_access(struct dma_buf *dma_buf,
const struct dma_buf_ops amdgpu_dmabuf_ops = { .dynamic_sgt_mapping = true, + .attach = amdgpu_gem_dma_buf_attach, + .pin = amdgpu_gem_pin_dma_buf, + .unpin = amdgpu_gem_unpin_dma_buf, .map_dma_buf = amdgpu_gem_map_dma_buf, .unmap_dma_buf = amdgpu_gem_unmap_dma_buf, .release = drm_gem_dmabuf_release,