[PATCH v2 08/25] arch: introduce memremap()

[Christoph Hellwig]

On Fri, Jul 24, 2015 at 10:38:42PM -0400, Dan Williams wrote:
> The behavior change to return NULL on an unsupported request is reserved
> for a later patch.

Why?

> +enum {
> +	MEMREMAP_WB = 1 << 0,
> +	MEMREMAP_WT = 1 << 1,
> +	MEMREMAP_CACHE = MEMREMAP_WB,

What's the point of having this MEMREMAP_CACHE alias?

Also please document the meaning of the flags for the poor users.