drm: GEM CMA: Add DRM PRIME support

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
diff --git a/include/drm/drm_gem_cma_helper.h b/include/drm/drm_gem_cma_helper.h
index 63397ce..6e17251 100644
--- a/include/drm/drm_gem_cma_helper.h
+++ b/include/drm/drm_gem_cma_helper.h
@@ -4,6 +4,9 @@
 struct drm_gem_cma_object {
 	struct drm_gem_object base;
 	dma_addr_t paddr;
+	struct sg_table *sgt;
+
+	/* For objects with DMA memory allocated by GEM CMA */
 	void *vaddr;
 };
 
@@ -45,4 +48,10 @@
 void drm_gem_cma_describe(struct drm_gem_cma_object *obj, struct seq_file *m);
 #endif
 
+struct dma_buf *drm_gem_cma_dmabuf_export(struct drm_device *drm_dev,
+					  struct drm_gem_object *obj,
+					  int flags);
+struct drm_gem_object *drm_gem_cma_dmabuf_import(struct drm_device *drm_dev,
+						 struct dma_buf *dma_buf);
+
 #endif /* __DRM_GEM_CMA_HELPER_H__ */