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Date: Thu, 20 Sep 2012 17:06:32 -0700
From: Tejun Heo <tj@kernel.org>
To: Kent Overstreet <koverstreet@google.com>
Cc: linux-bcache@vger.kernel.org, linux-kernel@vger.kernel.org,
        dm-devel@redhat.com, axboe@kernel.dk, neilb@suse.de
Subject: Re: [PATCH v2 15/26] block: Add bio_copy_data()
Message-ID: <20120921000632.GS7264@google.com>
References: <1347322957-25260-1-git-send-email-koverstreet@google.com>
 <1347322957-25260-16-git-send-email-koverstreet@google.com>
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Hello,

On Mon, Sep 10, 2012 at 05:22:26PM -0700, Kent Overstreet wrote:
> +void bio_copy_data(struct bio *dst, struct bio *src)
> +{
...
> +		src_p = kmap_atomic(src_bv->bv_page);
> +		dst_p = kmap_atomic(dst_bv->bv_page);
> +
> +		memcpy(dst_p + dst_bv->bv_offset,
> +		       src_p + src_bv->bv_offset,
> +		       bytes);
> +
> +		kunmap_atomic(dst_p);
> +		kunmap_atomic(src_p);

Wrap these in preempt_disable/enable() to allow the function to be
called from any context?

Thanks.

-- 
tejun