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Date:   Sat, 19 Jan 2019 02:25:27 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Liam Mark <lmark@codeaurora.org>
Cc:     labbott@redhat.com, sumit.semwal@linaro.org, arve@android.com,
        tkjos@android.com, maco@android.com, joel@joelfernandes.org,
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        dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org,
        linux-kernel@vger.kernel.org, afd@ti.com, john.stultz@linaro.org
Subject: Re: [PATCH 3/4] dma-buf: add support for mapping with dma mapping
 attributes
Message-ID: <20190119102527.GA17723@infradead.org>
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On Fri, Jan 18, 2019 at 10:37:46AM -0800, Liam Mark wrote:
> Add support for configuring dma mapping attributes when mapping
> and unmapping memory through dma_buf_map_attachment and
> dma_buf_unmap_attachment.
> 
> Signed-off-by: Liam Mark <lmark@codeaurora.org>

And who is going to decide which ones to pass?  And who documents
which ones are safe?

I'd much rather have explicit, well documented dma-buf flags that
might get translated to the DMA API flags, which are not error checked,
not very well documented and way to easy to get wrong.