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Date:   Mon, 11 Jun 2018 10:19:38 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Ming Lei <ming.lei@redhat.com>
Cc:     Jens Axboe <axboe@fb.com>, Christoph Hellwig <hch@infradead.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Kent Overstreet <kent.overstreet@gmail.com>,
        David Sterba <dsterba@suse.cz>,
        Huang Ying <ying.huang@intel.com>,
        linux-kernel@vger.kernel.org, linux-block@vger.kernel.org,
        linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
        Theodore Ts'o <tytso@mit.edu>,
        "Darrick J . Wong" <darrick.wong@oracle.com>,
        Coly Li <colyli@suse.de>, Filipe Manana <fdmanana@gmail.com>,
        Randy Dunlap <rdunlap@infradead.org>
Subject: Re: [PATCH V6 08/30] block: introduce chunk_last_segment()
Message-ID: <20180611171938.GA5101@infradead.org>
References: <20180609123014.8861-1-ming.lei@redhat.com>
 <20180609123014.8861-9-ming.lei@redhat.com>
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I think both callers would be just as easy to understand by using
nth_page() instead of these magic helpers.  E.g. for guard_bio_eod:

		unsigned offset = (bv.bv_offset + bv.bv_len);
		struct page *page = nth_page(bv.bv_page, offset);

		zero_user(page, offset & PAGE_MASK, truncated_bytes);