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Date: Fri, 16 Jun 2017 10:47:01 +0200
From: Christoph Hellwig <hch@lst.de>
To: Julian Calaby <julian.calaby@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>, x86@kernel.org,
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Subject: Re: [PATCH 28/44] sparc: remove arch specific dma_supported
 implementations
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On Fri, Jun 09, 2017 at 12:22:48AM +1000, Julian Calaby wrote:
> I'm guessing there's a few places that have DMA ops but DMA isn't
> actually supported. Why not have a common method for this, maybe
> "dma_not_supported"?

It's not common at all.  Except for sbus all dma API user first
call set_dma_mask which ends up in the dma_supported call.  sbus
is the weird outlier here.