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Date: Mon, 31 Oct 2016 08:29:01 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Ming Lei <tom.leiming@gmail.com>
Cc: Jens Axboe <axboe@fb.com>, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH 09/60] dm: dm.c: replace 'bio->bi_vcnt == 1' with
 !bio_multiple_segments
Message-ID: <20161031152901.GD30919@infradead.org>
References: <1477728600-12938-1-git-send-email-tom.leiming@gmail.com>
 <1477728600-12938-10-git-send-email-tom.leiming@gmail.com>
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On Sat, Oct 29, 2016 at 04:08:08PM +0800, Ming Lei wrote:
> Avoid to access .bi_vcnt directly, because it may be not what
> the driver expected any more after supporting multipage bvec.
> 
> Signed-off-by: Ming Lei <tom.leiming@gmail.com>

It would be really nice to have a comment in the code why it's
even checking for multiple segments.