Re: [PATCH v5 2/7] dma: Add simple dma_noop_mmap

From: Vladimir Murzin
Date: Thu Jun 22 2017 - 08:46:27 EST

On 20/06/17 14:23, Christoph Hellwig wrote:
> On Wed, May 24, 2017 at 11:24:27AM +0100, Vladimir Murzin wrote:
>> This patch adds a simple implementation of mmap to dma_noop_ops.
> Currently we use dma_common_mmap as the generic fallback if a dma_ops
> instance doesn't implement a mmap method. Can you just fix up
> dma_common_mmap for your nommu case - it looks like yours is basically
> a subset.

dma_common_map() is guarded with CONFIG_MMU and I'm not dare to change that
since I have no idea 1) why it was done 2) how it affects other arches :(

> In fact I suspect yours should call dma_mmap_from_coherent as well,
> so the only different is the lack of pgprot_noncached call.

OK, I'll add a call to dma_mmap_from_coherent().