Re: [RFC v3 02/45] dma-mapping: Use unsigned long for dma_attrs

Geert Uytterhoeven
2016-06-03T07:17:00Z

Hi Krzysztof,

On Thu, Jun 2, 2016 at 5:39 PM, Krzysztof Kozlowski
<k.kozlowski-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org> wrote:
> --- a/include/linux/dma-mapping.h
> +++ b/include/linux/dma-mapping.h
> @@ -5,13 +5,25 @@

> +/**
> + * List of possible attributes associated with a DMA mapping. The semantics
> + * of each attribute should be defined in Documentation/DMA-attributes.txt.
> + */
> +#define DMA_ATTR_WRITE_BARRIER (1UL << 1)

Any particular reason they start at 2, not 1?

> +#define DMA_ATTR_WEAK_ORDERING (1UL << 2)
> +#define DMA_ATTR_WRITE_COMBINE (1UL << 3)
> +#define DMA_ATTR_NON_CONSISTENT (1UL << 4)
> +#define DMA_ATTR_NO_KERNEL_MAPPING (1UL << 5)
> +#define DMA_ATTR_SKIP_CPU_SYNC (1UL << 6)
> +#define DMA_ATTR_FORCE_CONTIGUOUS (1UL << 7)
> +#define DMA_ATTR_ALLOC_SINGLE_PAGES (1UL << 8)

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds