Re: [PATCH v8 10/10] mm: Renumber FOLL_PIN and FOLL_GET down

From: Jason Gunthorpe
Date: Tue Jan 24 2023 - 08:46:32 EST


On Tue, Jan 24, 2023 at 05:18:07AM -0800, Christoph Hellwig wrote:
> On Tue, Jan 24, 2023 at 09:13:30AM -0400, Jason Gunthorpe wrote:
> > Yeah, I already wrote a similar patch, using the 1<< notation,
> > splitting the internal/external, and rebasing on the move to
> > mm_types.. I can certainly drop that patch if we'd rather do this.
>
> Given that you are doing more work in that area it might be best
> to drop this patch from this series.
>
> > Though, I'm not so keen on using FOLL_ internal flags inside the block
> > layer.. Can you stick with the BIO versions of these?
>
> The block layer doesn't really use it - the new helper in iov_iter.c
> returns it, and the block layer instantly turns it into an internal
> flag. But maybe it should just return a bool pinned (by reference)
> now?

Yes, a bool flag to the new mm helper instead of a FOLL_* seems good
to me

Thanks,
Jason