[PATCH v2 1/8] ethdev: add IPv6 routing extension header definition

[Andrew Rybchenko]

On 1/19/23 06:11, Rongwei Liu wrote:
> Add IPv6 routing extension header definition and no
> TLV support for now.
> 
> At rte_flow layer, there are new items defined for matching
> type/nexthdr/segments_left field.
> 
> Add command line support for IPv6 routing extension header
> matching: type/nexthdr/segment_list.
> 
> Signed-off-by: Rongwei Liu <rongweil at nvidia.com>
> Acked-by: Ori Kam <orika at nvidia.com>

[snip]

> diff --git a/doc/guides/prog_guide/rte_flow.rst b/doc/guides/prog_guide/rte_flow.rst
> index 3e6242803d..ae99036be0 100644
> --- a/doc/guides/prog_guide/rte_flow.rst
> +++ b/doc/guides/prog_guide/rte_flow.rst
> @@ -1544,6 +1544,15 @@ Matches Color Marker set by a Meter.
>   
>   - ``color``: Metering color marker.
>   
> +Item: ``IPV6_ROUTING_EXT``
> +^^^^^^^^^^^^^^^^^^^^^^^^^^
> +
> +Matches ipv6 routing extension header.

ipv6 -> IPv6

> +
> +- ``next_hdr``: Next layer header type.
> +- ``type``: IPv6 routing extension header type.
> +- ``segments_left``: How many IPv6 destination addresses carries on

Why are only 3 fields mentioned above?

> +
>   Actions
>   ~~~~~~~
>   
> diff --git a/doc/guides/rel_notes/release_23_03.rst b/doc/guides/rel_notes/release_23_03.rst
> index b8c5b68d6c..2a794d598e 100644
> --- a/doc/guides/rel_notes/release_23_03.rst
> +++ b/doc/guides/rel_notes/release_23_03.rst
> @@ -55,6 +55,11 @@ New Features
>        Also, make sure to start the actual text at the margin.
>        =======================================================
>   
> +* **Added rte_flow support for matching IPv6 routing extension header fields.**
> +
> +  Added ``ipv6_routing_ext`` items in rte_flow to match IPv6 routing extension
> +  header

Missing full stop above.

> +
>   
>   Removed Items
>   -------------
> @@ -84,6 +89,11 @@ API Changes
>      Also, make sure to start the actual text at the margin.
>      =======================================================
>   
> +* ethdev: added a new structure:
> +
> +    - IPv6 routing extension header ``rte_flow_item_ipv6_routing_ext`` and
> +      ``rte_ipv6_routing_ext``
> +

If I'm not mistaken, additions should not be here. It is not an
API change.

>   
>   ABI Changes
>   -----------
> diff --git a/lib/ethdev/rte_flow.c b/lib/ethdev/rte_flow.c
> index 7d0c24366c..4074b475c8 100644
> --- a/lib/ethdev/rte_flow.c
> +++ b/lib/ethdev/rte_flow.c
> @@ -76,6 +76,20 @@ rte_flow_item_flex_conv(void *buf, const void *data)
>   	return src->length;
>   }
>   
> +static size_t
> +rte_flow_item_ipv6_routing_ext_conv(void *buf, const void *data)
> +{
> +	struct rte_flow_item_ipv6_routing_ext *dst = buf;
> +	const struct rte_flow_item_ipv6_routing_ext *src = data;
> +	size_t len;
> +
> +	len = src->hdr.hdr_len ? src->hdr.hdr_len << 3 : src->hdr.segments_left << 4;

Compare hdr_len vs 0 explicitly.
Also I'd add parenthesis around ternary operator
values to make it simpler to understand.

> +	if (buf)

Please, compare vs NULL explicitly. May be 'dst' would be
better here?

> +		rte_memcpy((void *)((uintptr_t)(dst->hdr.segments)),
> +			   src->hdr.segments, len);
> +	return len;
> +}
> +
>   /** Generate flow_item[] entry. */
>   #define MK_FLOW_ITEM(t, s) \
>   	[RTE_FLOW_ITEM_TYPE_ ## t] = { \
> @@ -157,6 +171,8 @@ static const struct rte_flow_desc_data rte_flow_desc_item[] = {
>   	MK_FLOW_ITEM(L2TPV2, sizeof(struct rte_flow_item_l2tpv2)),
>   	MK_FLOW_ITEM(PPP, sizeof(struct rte_flow_item_ppp)),
>   	MK_FLOW_ITEM(METER_COLOR, sizeof(struct rte_flow_item_meter_color)),
> +	MK_FLOW_ITEM_FN(IPV6_ROUTING_EXT, sizeof(struct rte_flow_item_ipv6_routing_ext),
> +			rte_flow_item_ipv6_routing_ext_conv),
>   };
>   
>   /** Generate flow_action[] entry. */
> diff --git a/lib/ethdev/rte_flow.h b/lib/ethdev/rte_flow.h
> index b60987db4b..0120d3e7d2 100644
> --- a/lib/ethdev/rte_flow.h
> +++ b/lib/ethdev/rte_flow.h
> @@ -624,6 +624,13 @@ enum rte_flow_item_type {
>   	 * See struct rte_flow_item_meter_color.
>   	 */
>   	RTE_FLOW_ITEM_TYPE_METER_COLOR,
> +
> +	/**
> +	 * Matches the presence of IPv6 routing extension header.
> +	 *
> +	 * See struct rte_flow_item_ipv6_routing_ext.

@see

> +	 */
> +	RTE_FLOW_ITEM_TYPE_IPV6_ROUTING_EXT,
>   };
>   
>   /**
> @@ -873,6 +880,18 @@ struct rte_flow_item_ipv6 {
>   	uint32_t reserved:23;
>   };
>   
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this structure may change without prior notice
> + *
> + * RTE_FLOW_ITEM_TYPE_IPV6_ROUTING_EXT.
> + *
> + * Matches an IPv6 routing extension header.
> + */
> +struct rte_flow_item_ipv6_routing_ext {
> +	struct rte_ipv6_routing_ext hdr;
> +};
> +

What about default mask?

>   /** Default mask for RTE_FLOW_ITEM_TYPE_IPV6. */
>   #ifndef __cplusplus
>   static const struct rte_flow_item_ipv6 rte_flow_item_ipv6_mask = {
> diff --git a/lib/net/rte_ip.h b/lib/net/rte_ip.h
> index 9c8e8206f0..158a2f83ce 100644
> --- a/lib/net/rte_ip.h
> +++ b/lib/net/rte_ip.h
> @@ -539,6 +539,27 @@ struct rte_ipv6_hdr {
>   	uint8_t  dst_addr[16];	/**< IP address of destination host(s). */
>   } __rte_packed;
>   
> +/**
> + * IPv6 Routing Extension Header
> + */
> +struct rte_ipv6_routing_ext {
> +	uint8_t next_hdr;			/**< Protocol, next header. */
> +	uint8_t hdr_len;			/**< Header length. */
> +	uint8_t type;				/**< Extension header type. */
> +	uint8_t segments_left;			/**< Valid segments number. */
> +	__extension__
> +	union {
> +		uint32_t flags;

rte_be32_t ?

> +		struct {
> +			uint8_t last_entry;	/**< The last_entry field of SRH */
> +			uint8_t flag;		/**< Packet flag. */
> +			uint16_t tag;		/**< Packet tag. */

rte_be16_t

> +		};
> +	};
> +	__extension__
> +	uint32_t segments[0];			/**< Each hop IPv6 address. */

rte_be32_t

> +} __rte_packed;
> +
>   /* IPv6 vtc_flow: IPv / TC / flow_label */
>   #define RTE_IPV6_HDR_FL_SHIFT 0
>   #define RTE_IPV6_HDR_TC_SHIFT 20