[Query] doubt on parameters passed to dma_map_single_attrs() API

Tue Mar 22 05:34:08 PDT 2016

On Tue, Mar 22, 2016 at 03:53:02PM +0530, Sodagudi Prasad wrote:
> 
> Hi All,
> 
> Would like to check whether the dma_map_single_attrs() API, can accept ptr
> variable from high memory or not?

It can't.  Direct mapped, lowmem only.

No pointers allowed from dma_alloc_coherent(), dma_alloc_writecombine(),
ioremap(), vmalloc(), kmap(), kmap_atomic() or similar function, or
derived from one of these.

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