Date:   Tue, 24 Jan 2023 22:30:09 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     David Howells <dhowells@redhat.com>
Cc:     John Hubbard <jhubbard@nvidia.com>,
        Christoph Hellwig <hch@infradead.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Matthew Wilcox <willy@infradead.org>,
        Jens Axboe <axboe@kernel.dk>, Jan Kara <jack@suse.cz>,
        Jeff Layton <jlayton@kernel.org>,
        David Hildenbrand <david@redhat.com>,
        Jason Gunthorpe <jgg@nvidia.com>,
        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>
Subject: Re: [PATCH v9 5/8] block: Replace BIO_NO_PAGE_REF with
 BIO_PAGE_REFFED with inverted logic
Message-ID: <Y9DMcThwiDnbVpQe@infradead.org>
References: <b7833fd7-eb7d-2365-083d-5a01b9fee464@nvidia.com>
 <20230124170108.1070389-1-dhowells@redhat.com>
 <20230124170108.1070389-6-dhowells@redhat.com>
 <1353771.1674595077@warthog.procyon.org.uk>
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On Tue, Jan 24, 2023 at 09:17:57PM +0000, David Howells wrote:
> John Hubbard <jhubbard@nvidia.com> wrote:
> 
> > > +	/* for now require references for all pages */
> > 
> > Maybe just delete this comment?
> 
> Christoph added that.  Presumably because this really should move to pinning
> or be replaced with iomap, but it's not straightforward either way.  Christoph?

Mostly because it adds the flag when allocating the bio, and not where
doing the gup.  If John thinks it adds more confusion than it helps, we
can drop the comment.

That being said you had a conversion in an earlier version of the
series, and once the current batch of patches is in we should
resurrected it ASAP as that will allow us to kill BIO_FLAG_REFFED.