Re: [RESEND2 PATCH 1/3] memremap: add MEMREMAP_WC flag

From: Greg Kroah-Hartman
Date: Mon Feb 08 2016 - 13:30:23 EST


On Mon, Feb 08, 2016 at 05:30:50PM +0000, Brian Starkey wrote:
> Add a flag to memremap() for writecombine mappings. Mappings satisfied
> by this flag will not be cached, however writes may be delayed or
> combined into more efficient bursts. This is most suitable for
> buffers written sequentially by the CPU for use by other DMA devices.
>
> Signed-off-by: Brian Starkey <brian.starkey@xxxxxxx>
> Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>
> ---
> include/linux/io.h | 1 +
> kernel/memremap.c | 15 +++++++++++++--
> 2 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/io.h b/include/linux/io.h
> index 32403b5..e2c8419 100644
> --- a/include/linux/io.h
> +++ b/include/linux/io.h
> @@ -135,6 +135,7 @@ enum {
> /* See memremap() kernel-doc for usage description... */
> MEMREMAP_WB = 1 << 0,
> MEMREMAP_WT = 1 << 1,
> + MEMREMAP_WC = 1 << 2,

You didn't update the documentation :(