Re: [PATCH] - GRU virtual -> physical translation

[Jack Steiner <steiner@sgi.com>]

On Mon, Jul 14, 2008 at 02:50:18PM -0500, Robin Holt wrote:
> On Mon, Jul 14, 2008 at 11:31:07AM -0500, Jack Steiner wrote:
> > On Mon, Jul 14, 2008 at 09:24:51AM -0700, Andrew Morton wrote:
> > > On Mon, 14 Jul 2008 09:52:55 -0500 Jack Steiner <steiner@sgi.com> wrote:
> > > 
> > > > On Fri, Jul 11, 2008 at 12:17:36PM -0700, Andrew Morton wrote:
> > > > > On Wed, 9 Jul 2008 14:14:39 -0500 Jack Steiner <steiner@sgi.com> wrote:
> > > > > 
> > > > > > Open code the equivalent to follow_page(). This eliminates the
> > > > > > requirement for an EXPORT of follow_page().
> > > > > 
> > > > > I'd prefer to export follow_page() - copying-n-pasting just to avoid
> > > > > exporting the darn thing is silly.
> > > > 
> > > > If follow_page() can be EXPORTed, I think that may make the most sense for
> > > > now.
> > > 
> > > What was Christoph's reason for objecting to the export?
> > 
> > No clue. Just a NACK.
> > 
> > Christoph???
> 
> Maybe I missed part of the discussion, but I thought follow_page() would
> not work because you need this to function in the interrupt context and
> locks would then need to be made irqsave/irqrestore.

Arggg. You are right. I forgot the issue with the pte locks.

Looks like I am back to the plan suggested by Nick. I'll add a
get_user_pte_fast() function to gup.c.

The pte lookup function is very similar to the get_user_pages_fast()
function.

Ignore the previous noise about follow_page().


--- jack