diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/drm/drm_gem_vram_helper.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/include/drm/drm_gem_vram_helper.h b/include/drm/drm_gem_vram_helper.h index ac217d768456..4f0e207ee097 100644 --- a/include/drm/drm_gem_vram_helper.h +++ b/include/drm/drm_gem_vram_helper.h @@ -34,11 +34,25 @@ struct vm_area_struct; * backed by VRAM. It can be used for simple framebuffer devices with * dedicated memory. The buffer object can be evicted to system memory if * video memory becomes scarce. + * + * GEM VRAM objects perform reference counting for pin and mapping + * operations. So a buffer object that has been pinned N times with + * drm_gem_vram_pin() must be unpinned N times with + * drm_gem_vram_unpin(). The same applies to pairs of + * drm_gem_vram_kmap() and drm_gem_vram_kunmap(). */ struct drm_gem_vram_object { struct ttm_buffer_object bo; struct ttm_bo_kmap_obj kmap; + /** + * @kmap_use_count: + * + * Reference count on the virtual address. + * The address are un-mapped when the count reaches zero. + */ + unsigned int kmap_use_count; + /* Supported placements are %TTM_PL_VRAM and %TTM_PL_SYSTEM */ struct ttm_placement placement; struct ttm_place placements[2]; |