Re: [RFC PATCH 1/4] rtnetlink: new flag NLM_F_HW_OFFLOAD to indicate kernel object offload to hardware

[Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>]

Hello.

On 11/22/2014 1:49 AM, roopa@cumulusnetworks.com wrote:

> From: Roopa Prabhu <roopa@cumulusnetworks.com>

> This patch adds new flags in netlink header nlmsg_flags to signal if the
> message is for the kernel, hw or both.

> This can be used to indicate hw offload for all kind of objects
> routes, fdb entries, neighs, link objects like bonds, bridges, vxlan.

> Adding it in the header makes it possible to use it accross all objects and
> across all messages (sets/gets/deletes).

> Other alternative to this is a per kernel object netlink attribute/flag.
> But that leads to duplicating the attribute in different subsystems.

> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
> ---
>   include/uapi/linux/netlink.h |    2 ++
>   1 file changed, 2 insertions(+)

> diff --git a/include/uapi/linux/netlink.h b/include/uapi/linux/netlink.h
> index 1a85940..f78522d 100644
> --- a/include/uapi/linux/netlink.h
> +++ b/include/uapi/linux/netlink.h
> @@ -54,6 +54,8 @@ struct nlmsghdr {
>   #define NLM_F_ACK		4	/* Reply with ack, with zero or error code */
>   #define NLM_F_ECHO		8	/* Echo this request 		*/
>   #define NLM_F_DUMP_INTR		16	/* Dump was inconsistent due to sequence change */
> ++#define NLM_F_KERNEL       32      /* This msg is only for the kernel */

    I don't think you really meant double '+'.

> +#define NLM_F_HW_OFFLOAD	64	/* offload this msg to hw */
[...]

WBR, Sergei