Re: pmap_enter(9) rework

["Toru Nishimura" <runqueue128%alkyltechnology.com@localhost>]

The reason why NB pmap_enter(9) implementation
so vary among processors are the definition and
usage of pmap_enter(9) by upper VM layer is incorrect
or less matched with HW realities.  The most scareful
situation is the necessity to track the change of existing
pg attribute inside pmap_enter.  It invovles complicated
case analysis., but in essense the case analysis is
common across processors.

Toru Nishimura / ALKYL Technology / Sanctum Networks