drm/amdgpu: add amdgpu_dma_buf_pin/unpin v2

This implements the exporter side of unpinned DMA-buf handling.

v2: fix minor coding style issues

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/353999/?series=73646&rev=1

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
index 7cafc65..86000c7 100644 (file)
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c
@@ -223,6 +223,37 @@ static void amdgpu_dma_buf_detach(struct dma_buf *dmabuf,
 }
 
 /**
+ * amdgpu_dma_buf_pin - &dma_buf_ops.pin implementation
+ *
+ * @attach: attachment to pin down
+ *
+ * Pin the BO which is backing the DMA-buf so that it can't move any more.
+ */
+static int amdgpu_dma_buf_pin(struct dma_buf_attachment *attach)
+{
+       struct drm_gem_object *obj = attach->dmabuf->priv;
+       struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
+
+       /* pin buffer into GTT */
+       return amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT);
+}
+
+/**
+ * amdgpu_dma_buf_unpin - &dma_buf_ops.unpin implementation
+ *
+ * @attach: attachment to unpin
+ *
+ * Unpin a previously pinned BO to make it movable again.
+ */
+static void amdgpu_dma_buf_unpin(struct dma_buf_attachment *attach)
+{
+       struct drm_gem_object *obj = attach->dmabuf->priv;
+       struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
+
+       amdgpu_bo_unpin(bo);
+}
+
+/**
  * amdgpu_dma_buf_map - &dma_buf_ops.map_dma_buf implementation
  * @attach: DMA-buf attachment
  * @dir: DMA direction
@@ -244,9 +275,19 @@ static struct sg_table *amdgpu_dma_buf_map(struct dma_buf_attachment *attach,
        struct sg_table *sgt;
        long r;
 
-       r = amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT);
-       if (r)
-               return ERR_PTR(r);
+       if (!bo->pin_count) {
+               /* 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);
+
+       } else if (!(amdgpu_mem_type_to_domain(bo->tbo.mem.mem_type) &
+                    AMDGPU_GEM_DOMAIN_GTT)) {
+               return ERR_PTR(-EBUSY);
+       }
 
        sgt = drm_prime_pages_to_sg(bo->tbo.ttm->pages, bo->tbo.num_pages);
        if (IS_ERR(sgt))
@@ -277,13 +318,9 @@ static void amdgpu_dma_buf_unmap(struct dma_buf_attachment *attach,
                                 struct sg_table *sgt,
                                 enum dma_data_direction dir)
 {
-       struct drm_gem_object *obj = attach->dmabuf->priv;
-       struct amdgpu_bo *bo = gem_to_amdgpu_bo(obj);
-
        dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents, dir);
        sg_free_table(sgt);
        kfree(sgt);
-       amdgpu_bo_unpin(bo);
 }
 
 /**
@@ -330,6 +367,8 @@ const struct dma_buf_ops amdgpu_dmabuf_ops = {
        .dynamic_mapping = true,
        .attach = amdgpu_dma_buf_attach,
        .detach = amdgpu_dma_buf_detach,
+       .pin = amdgpu_dma_buf_pin,
+       .unpin = amdgpu_dma_buf_unpin,
        .map_dma_buf = amdgpu_dma_buf_map,
        .unmap_dma_buf = amdgpu_dma_buf_unmap,
        .release = drm_gem_dmabuf_release,

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
index e3f16b4..9de8374 100644 (file)
--- 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/amdgpu_drm.h>
 #include <drm/drm_cache.h>
@@ -1274,6 +1275,10 @@ void amdgpu_bo_move_notify(struct ttm_buffer_object *bo,
 
        amdgpu_bo_kunmap(abo);
 
+       if (abo->tbo.base.dma_buf && !abo->tbo.base.import_attach &&
+           bo->mem.mem_type != TTM_PL_SYSTEM)
+               dma_buf_move_notify(abo->tbo.base.dma_buf);
+
        /* remember the eviction */
        if (evict)
                atomic64_inc(&adev->num_evictions);