Re: [patch 3/6] arch_update_pgd call

Benjamin Herrenschmidt
2007-10-26T07:59:03Z

On Fri, 2007-10-26 at 09:40 +0200, Martin Schwidefsky wrote:
> On Fri, 2007-10-26 at 06:48 +1000, Benjamin Herrenschmidt wrote:
> > On Thu, 2007-10-25 at 20:15 +0200, Martin Schwidefsky wrote:
> > > plain text document attachment (003-mm-update-pgd.diff)
> > > From: Martin Schwidefsky <schwidefsky@de.ibm.com>
> > >
> > > In order to change the layout of the page tables after an mmap has
> > > crossed the adress space limit of the current page table layout a
> > > architecture hook in get_unmapped_area is needed. The arguments
> > > are the address of the new mapping and the length of it.
> > >
> > > Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
> >
> > I'm not at all fan of the hook there and it's name...
> >
> > Any reason why you can't do that in your arch gua ?
> >
> > If not, then why can't you call it something nicer, like
> > arch_rebalance_pgtables() ?
>
> The name can be changed in no time. I've tried to use one of the
> existing arch calls like arch_mmap_check or arch_get_unmapped_area but
> it didn't work out. I really need the final address to make the call to
> extend the page tables.

You arch get_unmapped_area() has it...

Ben.