1 files changed, 48 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c
index 1bdf2b5..f546ff9 100644
--- a/drivers/gpu/drm/drm_prime.c
+++ b/drivers/gpu/drm/drm_prime.c
@@ -68,6 +68,7 @@ int drm_gem_prime_handle_to_fd(struct drm_device *dev,
 {
 	struct drm_gem_object *obj;
 	void *buf;
+	int ret;
 
 	obj = drm_gem_object_lookup(dev, file_priv, handle);
 	if (!obj)
@@ -100,6 +101,17 @@ int drm_gem_prime_handle_to_fd(struct drm_device *dev,
 		obj->export_dma_buf = buf;
 		*prime_fd = dma_buf_fd(buf, flags);
 	}
+	/* if we've exported this buffer the cheat and add it to the import list
+	 * so we get the correct handle back
+	 */
+	ret = drm_prime_add_imported_buf_handle(&file_priv->prime,
+			obj->export_dma_buf, handle);
+	if (ret) {
+		drm_gem_object_unreference_unlocked(obj);
+		mutex_unlock(&file_priv->prime.lock);
+		return ret;
+	}
+
 	mutex_unlock(&file_priv->prime.lock);
 	return 0;
 }
@@ -227,6 +239,42 @@ out:
 }
 EXPORT_SYMBOL(drm_prime_pages_to_sg);
 
+/* export an sg table into an array of pages and addresses
+   this is currently required by the TTM driver in order to do correct fault
+   handling */
+int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages,
+				     dma_addr_t *addrs, int max_pages)
+{
+	unsigned count;
+	struct scatterlist *sg;
+	struct page *page;
+	u32 len, offset;
+	int pg_index;
+	dma_addr_t addr;
+
+	pg_index = 0;
+	for_each_sg(sgt->sgl, sg, sgt->nents, count) {
+		len = sg->length;
+		offset = sg->offset;
+		page = sg_page(sg);
+		addr = sg_dma_address(sg);
+
+		while (len > 0) {
+			if (WARN_ON(pg_index >= max_pages))
+				return -1;
+			pages[pg_index] = page;
+			if (addrs)
+				addrs[pg_index] = addr;
+
+			page++;
+			addr += PAGE_SIZE;
+			len -= PAGE_SIZE;
+			pg_index++;
+		}
+	}
+	return 0;
+}
+EXPORT_SYMBOL(drm_prime_sg_to_page_addr_arrays);
 /* helper function to cleanup a GEM/prime object */
 void drm_prime_gem_destroy(struct drm_gem_object *obj, struct sg_table *sg)
 {