Date:   Tue, 24 Jan 2023 11:02:57 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     David Howells <dhowells@redhat.com>
Cc:     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>,
        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 6/8] block: Switch to pinning pages.
Message-ID: <Y9ArYfXEix7t3gVI@infradead.org>
References: <20230124170108.1070389-1-dhowells@redhat.com>
 <20230124170108.1070389-7-dhowells@redhat.com>
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On Tue, Jan 24, 2023 at 05:01:06PM +0000, David Howells wrote:
> Add BIO_PAGE_PINNED to indicate that the pages in a bio are pinned
> (FOLL_PIN) and that the pin will need removing.

The subject is odd when this doesn't actually switch anything,
but just adds the infrastructure to unpin pages.

> +/*
> + * Set the cleanup mode for a bio from an iterator and the extraction flags.
> + */
> +static inline void bio_set_cleanup_mode(struct bio *bio, struct iov_iter *iter)
> +{
> +	if (iov_iter_extract_will_pin(iter))
> +		bio_set_flag(bio, BIO_PAGE_PINNED);
> +}

At this point I'd be tempted to just open code these two lines
instead of adding a helper, but I can live with the helper if you
prefer it.

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@lst.de>