buffer: add data_ptr access flags

This allows callers to specify the operations they'll perform on
the returned data pointer. The motivations for this are:

- The upcoming Linux MAP_NOSIGBUS flag may only be usable on
  read-only mappings.
- gbm_bo_map with GBM_BO_TRANSFER_READ hurts performance.

1 files changed, 2 insertions, 1 deletions

diff --git a/render/gles2/texture.c b/render/gles2/texture.c
index 0368c1a1..64ac05ac 100644
--- a/render/gles2/texture.c
+++ b/render/gles2/texture.c
@@ -346,7 +346,8 @@ struct wlr_texture *gles2_texture_from_buffer(struct wlr_renderer *wlr_renderer,
 	struct wlr_dmabuf_attributes dmabuf;
 	if (wlr_buffer_get_dmabuf(buffer, &dmabuf)) {
 		return gles2_texture_from_dmabuf_buffer(renderer, buffer, &dmabuf);
-	} else if (buffer_begin_data_ptr_access(buffer, &data, &format, &stride)) {
+	} else if (buffer_begin_data_ptr_access(buffer,
+			WLR_BUFFER_DATA_PTR_ACCESS_READ, &data, &format, &stride)) {
 		struct wlr_texture *tex = gles2_texture_from_pixels(wlr_renderer,
 			format, stride, buffer->width, buffer->height, data);
 		buffer_end_data_ptr_access(buffer);