In vmapbuf(), instead of invoking pmap_cache_ctrl() for each page, postpone the call and process the whole range once.
In vmapbuf(), instead of invoking pmap_cache_ctrl() for each page, postpone
the call and process the whole range once.

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars