Subject: Re: [PATCH] block: don't optimize for non-cloned bio in
 bio_get_last_bvec()
To: Ming Lei <ming.lei@canonical.com>, linux-kernel@vger.kernel.org
References: <1457794579-6125-1-git-send-email-ming.lei@canonical.com>
Cc: linux-block@vger.kernel.org, Christoph Hellwig <hch@infradead.org>,
        Sagi Grimberg <sagig@dev.mellanox.co.il>,
        Kent Overstreet <kent.overstreet@gmail.com>, stable@vger.kernel.org
From: Jens Axboe <axboe@kernel.dk>
Message-ID: <56E4E575.5020303@kernel.dk>
Date: Sat, 12 Mar 2016 20:58:45 -0700
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On 03/12/2016 07:56 AM, Ming Lei wrote:
> For !BIO_CLONED bio, we can use .bi_vcnt safely, but it
> doesn't mean we can just simply return .bi_io_vec[.bi_vcnt - 1]
> because the start postion may have been moved in the middle of
> the bvec, such as splitting in the middle of bvec.

Added and tested.

-- 
Jens Axboe