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Subject: Re: fix a layering violation in videobuf2 and improve
 dma_map_resource
To:     Christoph Hellwig <hch@lst.de>, Pawel Osciak <pawel@osciak.com>,
        Kyungmin Park <kyungmin.park@samsung.com>,
        =?UTF-8?Q?Niklas_S=c3=b6derlund?= 
        <niklas.soderlund+renesas@ragnatech.se>
Cc:     Russell King <linux@armlinux.org.uk>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        iommu@lists.linux-foundation.org,
        linux-arm-kernel@lists.infradead.org,
        linuxppc-dev@lists.ozlabs.org, linux-media@vger.kernel.org,
        linux-kernel@vger.kernel.org
From:   Marek Szyprowski <m.szyprowski@samsung.com>
Message-ID: <141501f5-a9f4-98d7-e958-ca40fc870454@samsung.com>
Date:   Mon, 14 Jan 2019 12:43:03 +0100
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Hi Christoph,

On 2019-01-11 19:17, Christoph Hellwig wrote:
> Hi all,
>
> this series fixes a rather gross layering violation in videobuf2, which
> pokes into arm DMA mapping internals to get a DMA address for memory that
> does not have a page structure, and to do so fixes up the dma_map_resource
> implementation to be practically useful.

Thanks for rewriting this 'temporary code'! It predates
dma_map_resource() and that time this was the only way to get it working
somehow. Good that now it is possible to implement in it a clean way
without any unwritten assumptions about the DMA mapping internals. Feel
free to add my:

Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com>

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland