[dpdk-dev] [RFC] ethdev: add IPv4/IPv6 DSCP rewrite action

[Andrew Rybchenko]

On 12/10/19 8:23 AM, Suanming Mou wrote:
> For some overlay network, such as VXLAN, the DSCP field in the new outer
> IP header after VXLAN decapsulation may need to be updated accordingly.
> 
> This commit introduce the DSCP modify action for IPv4 and IPv6.
> 
> Signed-off-by: Suanming Mou <suanmingm at mellanox.com>

Acked-by: Andrew Rybchenko <arybchenko at solarflare.com>

as usual it requires testpmd support and a driver which
supports it (I understand that it may be omitted in RFC).

Few minor notes below.

> ---
>  doc/guides/prog_guide/rte_flow.rst | 40 ++++++++++++++++++++++++++++++++++++++
>  lib/librte_ethdev/rte_flow.h       | 31 +++++++++++++++++++++++++++++
>  2 files changed, 71 insertions(+)
> 
> diff --git a/doc/guides/prog_guide/rte_flow.rst b/doc/guides/prog_guide/rte_flow.rst
> index a254c81..54b9250 100644
> --- a/doc/guides/prog_guide/rte_flow.rst
> +++ b/doc/guides/prog_guide/rte_flow.rst
> @@ -2558,6 +2558,46 @@ the other path depending on HW capability.
>     | ``mask`` | bit-mask applies to "data" |
>     +----------+----------------------------+
>  
> +Action: ``SET_IPV4_DSCP``
> +^^^^^^^^^^^^^^^^^^^^^^^^^
> +
> +Set IPv4DSCP.

I think it is better to have space between IPv4 and DSCP above.

> +
> +Modify DSCP in IPv4 header.
> +
> +It must be used with RTE_FLOW_ITEM_TYPE_IPV4 in pattern.
> +Otherwise, RTE_FLOW_ERROR_TYPE_ACTION error will be returned.
> +
> +.. _table_rte_flow_action_set_ipv4_dscp:
> +
> +.. table:: SET_IPV4_DSCP
> +
> +   +-----------+---------------------------------+
> +   | Field     | Value                           |
> +   +===========+=================================+
> +   | ``dscp``  | DSCP in low 6 bits, rest ingore |

ingore -> ignore

> +   +-----------+---------------------------------+
> +
> +Action: ``SET_IPV6_DSCP``
> +^^^^^^^^^^^^^^^^^^^^^^^^
> +
> +Set IPv6DSCP.

Same.

> +
> +Modify DSCP in IPv6 header.
> +
> +It must be used with RTE_FLOW_ITEM_TYPE_IPV6 in pattern.
> +Otherwise, RTE_FLOW_ERROR_TYPE_ACTION error will be returned.
> +
> +.. _table_rte_flow_action_set_ipv6_dscp:
> +
> +.. table:: SET_IPV6_DSCP
> +
> +   +-----------+---------------------------------+
> +   | Field     | Value                           |
> +   +===========+=================================+
> +   | ``dscp``  | DSCP in low 6 bits, rest ingore |

ingore -> ignore

> +   +-----------+---------------------------------+
> +
>  Negative types
>  ~~~~~~~~~~~~~~
>  
> diff --git a/lib/librte_ethdev/rte_flow.h b/lib/librte_ethdev/rte_flow.h
> index 452d359..76bf080 100644
> --- a/lib/librte_ethdev/rte_flow.h
> +++ b/lib/librte_ethdev/rte_flow.h
> @@ -2004,6 +2004,26 @@ enum rte_flow_action_type {
>  	 * See struct rte_flow_action_set_meta.
>  	 */
>  	RTE_FLOW_ACTION_TYPE_SET_META,
> +
> +	/**
> +	 * Modify IPv4 DSCP in the outermost IP header.
> +	 *
> +	 * If flow pattern does not define a valid RTE_FLOW_ITEM_TYPE_IPV4,
> +	 * then the PMD should return a RTE_FLOW_ERROR_TYPE_ACTION error.
> +	 *
> +	 * See struct rte_flow_action_set_dscp.
> +	 */
> +	RTE_FLOW_ACTION_TYPE_SET_IPV4_DSCP,
> +
> +	/**
> +	 * Modify IPv6 DSCP in the outermost IP header.
> +	 *
> +	 * If flow pattern does not define a valid RTE_FLOW_ITEM_TYPE_IPV6,
> +	 * then the PMD should return a RTE_FLOW_ERROR_TYPE_ACTION error.
> +	 *
> +	 * See struct rte_flow_action_set_dscp.
> +	 */
> +	RTE_FLOW_ACTION_TYPE_SET_IPV6_DSCP,
>  };
>  
>  /**
> @@ -2530,6 +2550,17 @@ struct rte_flow_action_set_meta {
>  	uint32_t mask;
>  };
>  
> +/**
> + * RTE_FLOW_ACTION_TYPE_SET_IPV4_DSCP
> + * RTE_FLOW_ACTION_TYPE_SET_IPV6_DSCP
> + *
> + * Set the DSCP value for IPv4/IPv6 header.
> + * DSCP in low 6 bits, rest ignored.
> + */
> +struct rte_flow_action_set_dscp {
> +	uint8_t dscp;
> +};
> +
>  /* Mbuf dynamic field offset for metadata. */
>  extern int rte_flow_dynf_metadata_offs;
>  
>