PQ_FIXED (was Re: XIP)

[Masao Uebayashi <uebayasi%tombi.co.jp@localhost>]

On Sun, Oct 31, 2010 at 02:27:33PM +0900, Masao Uebayashi wrote:
(snip)
> > > >  - as you guessed in your mail, I don't like the new PQ_FIXED flag 
> > > > either.
> > > >    it looks like it's only used for preventing the XIP pages from
> > > >    being put on the paging queues, but that would be better done by
> > > >    just initializing pg->wire_count to 1 so that UVM treats them
> > > >    as permanently non-pageable (which they actually are).
> > > 
> > > Are you OK to prevent XIP pages from being loaned? ;)
> > > 
> > > The actual problems here are
> > > 
> > >  a) the generic fault handler doesn't know how to handle pages that
> > >     never be paged out (device pages), and
(snip)

I'll revert the PQ_FIXED part.  Full vm_page is allocated for the
time being.