Date:   Tue, 24 Jan 2023 10:31:35 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     David Howells <dhowells@redhat.com>
Cc:     John Hubbard <jhubbard@nvidia.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Christoph Hellwig <hch@infradead.org>,
        Matthew Wilcox <willy@infradead.org>,
        Jens Axboe <axboe@kernel.dk>, Jan Kara <jack@suse.cz>,
        Jeff Layton <jlayton@kernel.org>,
        Logan Gunthorpe <logang@deltatee.com>,
        linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, Christoph Hellwig <hch@lst.de>,
        linux-mm@kvack.org
Subject: Re: [PATCH v8 10/10] mm: Renumber FOLL_PIN and FOLL_GET down
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On Tue, Jan 24, 2023 at 02:27:53PM +0000, David Howells wrote:
> Jason Gunthorpe <jgg@nvidia.com> wrote:
> 
> > My point was to change that to take a 'bool unpin' because FOLL_PIN is
> > not to be used outside gup.c
> 
> I need a 3-state wrapper.  But if I can't do it in gup.c, then I'll have to do
> it elsewhere.  As Christoph says, most of the places will only be pinned or
> not-pinned.  The whole point was to avoid generating new constants when
> existing constants would do.

What is the 3rd state?

Jason