drm/prime: introduce sg->pages/addr arrays helper

the ttm drivers need this currently, in order to get fault handling
working and efficient.

It also allows addrs to be NULL for devices like udl.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index 15d91798dd31..31ad880ca2ef 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1558,6 +1558,8 @@ extern int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data,
 extern int drm_prime_fd_to_handle_ioctl(struct drm_device *dev, void *data,
                                         struct drm_file *file_priv);
 
+extern int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages,
+                                            dma_addr_t *addrs, int max_pages);
 extern struct sg_table *drm_prime_pages_to_sg(struct page **pages, int nr_pages);
 extern void drm_prime_gem_destroy(struct drm_gem_object *obj, struct sg_table *sg);