diff options
Diffstat (limited to 'include/drm/drm_gem.h')
| -rw-r--r-- | include/drm/drm_gem.h | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h index a9121fe66ea2..ae693c0666cd 100644 --- a/include/drm/drm_gem.h +++ b/include/drm/drm_gem.h @@ -101,7 +101,7 @@ struct drm_gem_object_funcs { /** * @pin: * - * Pin backing buffer in memory. + * Pin backing buffer in memory. Used by the drm_gem_map_attach() helper. * * This callback is optional. */ @@ -110,7 +110,7 @@ struct drm_gem_object_funcs { /** * @unpin: * - * Unpin backing buffer. + * Unpin backing buffer. Used by the drm_gem_map_detach() helper. * * This callback is optional. */ @@ -120,16 +120,21 @@ struct drm_gem_object_funcs { * @get_sg_table: * * Returns a Scatter-Gather table representation of the buffer. - * Used when exporting a buffer. + * Used when exporting a buffer by the drm_gem_map_dma_buf() helper. + * Releasing is done by calling dma_unmap_sg_attrs() and sg_free_table() + * in drm_gem_unmap_buf(), therefore these helpers and this callback + * here cannot be used for sg tables pointing at driver private memory + * ranges. * - * This callback is mandatory if buffer export is supported. + * See also drm_prime_pages_to_sg(). */ struct sg_table *(*get_sg_table)(struct drm_gem_object *obj); /** * @vmap: * - * Returns a virtual address for the buffer. + * Returns a virtual address for the buffer. Used by the + * drm_gem_dmabuf_vmap() helper. * * This callback is optional. */ @@ -138,7 +143,8 @@ struct drm_gem_object_funcs { /** * @vunmap: * - * Releases the the address previously returned by @vmap. + * Releases the the address previously returned by @vmap. Used by the + * drm_gem_dmabuf_vunmap() helper. * * This callback is optional. */ |