drm: move pinning/unpinning to buffer attach

This allows importing bo's to own device to work without requiring that the buffer is pinned in GART.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/drm_prime.c

@@ -64,6 +64,29 @@ struct drm_prime_member {
 };
 static int drm_prime_add_buf_handle(struct drm_prime_file_private *prime_fpriv, struct dma_buf *dma_buf, uint32_t handle);
 
+static int drm_gem_map_attach(struct dma_buf *dma_buf,
+			      struct device *target_dev,
+			      struct dma_buf_attachment *attach)
+{
+	struct drm_gem_object *obj = dma_buf->priv;
+	struct drm_device *dev = obj->dev;
+
+	if (!dev->driver->gem_prime_pin)
+		return 0;
+
+	return dev->driver->gem_prime_pin(obj);
+}
+
+static void drm_gem_map_detach(struct dma_buf *dma_buf,
+			       struct dma_buf_attachment *attach)
+{
+	struct drm_gem_object *obj = dma_buf->priv;
+	struct drm_device *dev = obj->dev;
+
+	if (dev->driver->gem_prime_unpin)
+		dev->driver->gem_prime_unpin(obj);
+}
+
 static struct sg_table *drm_gem_map_dma_buf(struct dma_buf_attachment *attach,
 		enum dma_data_direction dir)
 {
@@ -92,13 +115,10 @@ static void drm_gem_unmap_dma_buf(struct dma_buf_attachment *attach,
 static void drm_gem_dmabuf_release(struct dma_buf *dma_buf)
 {
 	struct drm_gem_object *obj = dma_buf->priv;
-	struct drm_device *dev = obj->dev;
 
 	if (obj->export_dma_buf == dma_buf) {
 		/* drop the reference on the export fd holds */
 		obj->export_dma_buf = NULL;
-		if (dev->driver->gem_prime_unpin)
-			dev->driver->gem_prime_unpin(obj);
 		drm_gem_object_unreference_unlocked(obj);
 	}
 }
@@ -149,6 +169,8 @@ static int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf,
 }
 
 static const struct dma_buf_ops drm_gem_prime_dmabuf_ops =  {
+	.attach = drm_gem_map_attach,
+	.detach = drm_gem_map_detach,
 	.map_dma_buf = drm_gem_map_dma_buf,
 	.unmap_dma_buf = drm_gem_unmap_dma_buf,
 	.release = drm_gem_dmabuf_release,
@@ -188,19 +210,8 @@ static const struct dma_buf_ops drm_gem_prime_dmabuf_ops =  {
 struct dma_buf *drm_gem_prime_export(struct drm_device *dev,
 				     struct drm_gem_object *obj, int flags)
 {
-	struct dma_buf *buf;
-
-	if (dev->driver->gem_prime_pin) {
-		int ret = dev->driver->gem_prime_pin(obj);
-		if (ret)
-			return ERR_PTR(ret);
-	}
-	buf = dma_buf_export(obj, &drm_gem_prime_dmabuf_ops, obj->size,
+	return dma_buf_export(obj, &drm_gem_prime_dmabuf_ops, obj->size,
 			     0600);
-
-	if (IS_ERR(buf) && dev->driver->gem_prime_unpin)
-		dev->driver->gem_prime_unpin(obj);
-	return buf;
 }
 EXPORT_SYMBOL(drm_gem_prime_export);