drm_gem_create_mmap_offset_size — create a fake mmap offset for an object
int drm_gem_create_mmap_offset_size ( | struct drm_gem_object * obj, |
size_t size); |
GEM memory mapping works by handing back to userspace a fake mmap offset it can use in a subsequent mmap(2) call. The DRM core code then looks up the object based on the offset and sets up the various memory mapping structures.
This routine allocates and attaches a fake offset for obj, in cases where
the virtual size differs from the physical size (ie. obj->size). Otherwise
just use drm_gem_create_mmap_offset.