[PATCH 7/8] common: dma-mapping: change alloc/free_coherent method to more generic alloc/free_attrs

Arnd Bergmann arnd at arndb.de
Mon Jun 27 09:22:05 EDT 2011


On Monday 27 June 2011, Marek Szyprowski wrote:
> > On a related note, do you plan to make the CMA work use this
> > transparently, or do you want to have a DMA_ATTR_LARGE or
> > DMA_ATTR_CONTIGUOUS for CMA?
> 
> IMHO it will be better to hide the CMA from the drivers. Memory allocated
> from CMA doesn't really differ from the one allocated by dma_alloc_coherent()
> (which internally use alloc_pages()), so I really see no reason for adding
> additional attribute for it.

Ok, fair enough. On a semi-related topic, IIRC we still need to make sure
that dma_alloc_coherent() pages are unmapped from the linear mapping. I hope
this is independent of both CMA and this patch.

	Arnd



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