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Subject: Re: [RFC 0/8] Copy Offload with Peer-to-Peer PCI Memory
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Logan Gunthorpe <logang@deltatee.com>,
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Date: Wed, 19 Apr 2017 11:17:49 +1000
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On Tue, 2017-04-18 at 14:48 -0600, Logan Gunthorpe wrote:
> > ...and that dma_map goes through get_dma_ops(), so I don't see the conflict?
> 
> The main conflict is in dma_map_sg which only does get_dma_ops once but
> the sg may contain memory of different types.

We can handle that in our "overriden" dma ops.

It's a bit tricky but it *could* break it down into segments and
forward portions back to the original dma ops.

Ben.