Date:   Tue, 24 Jan 2023 06:52:51 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     David Howells <dhowells@redhat.com>
Cc:     David Hildenbrand <david@redhat.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 03/10] mm: Provide a helper to drop a pin/ref on a page
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On Tue, Jan 24, 2023 at 02:41:33PM +0000, David Howells wrote:
> Yes.  Christoph insisted that the bio conversion patch be split up.  That
> means there's an interval where you can get FOLL_GET from that.

The only place where we have both is in the block layer.  It never gets
set by bio_set_cleanup_mode.

Instead we can just keep using put_page dirctly for the BIO_PAGE_REFFED
case in the callers of bio_release_page and in bio_release_pages itself,
and then do away with bio_to_gup_flags and bio_release_page entirely.