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Date:   Fri, 10 Sep 2021 08:24:02 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Andreas Gruenbacher <agruenba@redhat.com>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        "Darrick J. Wong" <djwong@kernel.org>, Jan Kara <jack@suse.cz>,
        Matthew Wilcox <willy@infradead.org>,
        cluster-devel <cluster-devel@redhat.com>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        ocfs2-devel@oss.oracle.com
Subject: Re: [PATCH v7 17/19] gup: Introduce FOLL_NOFAULT flag to disable
 page faults
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On Thu, Sep 09, 2021 at 10:17:14AM -0700, Linus Torvalds wrote:
> So I think we should treat FOLL_FAST_ONLY as a special "internal to
> gup.c" flag, and perhaps not really compare it to the new
> FOLL_NOFAULT.
> 
> In fact, maybe we could even just make FOLL_FAST_ONLY be the high bit,
> and not expose it in <linux/mm.h> and make it entirely private as a
> name in gup.c.

There are quite a few bits like that.  I've been wanting to make them
private for 5.16.