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Date: Wed, 10 Jun 2015 00:35:26 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Ming Lei <ming.lei@canonical.com>
Cc: linux-kernel@vger.kernel.org, Dave Kleikamp <dave.kleikamp@oracle.com>,
        Jens Axboe <axboe@kernel.dk>, Zach Brown <zab@zabbo.net>,
        Christoph Hellwig <hch@infradead.org>,
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        Andrew Morton <akpm@linux-foundation.org>,
        Alexander Viro <viro@zeniv.linux.org.uk>, Tejun Heo <tj@kernel.org>,
        Dave Chinner <david@fromorbit.com>
Subject: Re: [PATCH v5 1/5] fs: direct-io: don't dirtying pages for
 ITER_BVEC/ITER_KVEC direct read
Message-ID: <20150610073526.GA6964@infradead.org>
References: <1433857766-6153-1-git-send-email-ming.lei@canonical.com>
 <1433857766-6153-2-git-send-email-ming.lei@canonical.com>
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On Tue, Jun 09, 2015 at 09:49:22PM +0800, Ming Lei wrote:
> When direct read IO is submitted from kernel, it is often
> unnecessary to dirty pages, for example of loop, dirtying pages
> have been considered in the upper filesystem(over loop) side
> already, and they don't need to be dirtied again.
> 
> So this patch doesn't dirtying pages for ITER_BVEC/ITER_KVEC
> direct read, and loop should be the 1st case to use ITER_BVEC/ITER_KVEC
> for direct read I/O.
> 
> The patch is based on previous Dave's patch.

Looks good, thanks!

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