[RFC V1 1/1] net: extend VXLAN header to support more extensions

[Thomas Monjalon]

30/01/2024 12:25, Gavin Li:
> In this patch, all the VXLAN extension header will be merged with VXLAN as
> union if the overlapped field has different format among protocols. The
> existing VXLAN-GPE will be marked as deprecated and new extensions of
> VXLAN should be added to VXLAN instead of a new RTE item.

So VXLAN GPE, GBP, and original ones will all use the same struct.
Asking confirmation to other reviewers:
- do we want to deprecate specific VXLAN GPE?
- do we want to plan for VXLAN GPE removal?

[...]
> --- a/doc/guides/rel_notes/deprecation.rst
> +++ b/doc/guides/rel_notes/deprecation.rst
> +* ethdev: The flow item ``RTE_FLOW_ITEM_TYPE_VXLAN_GPE`` is replaced with ``RTE_FLOW_ITEM_TYPE_VXLAN``.
> +  The item ``RTE_FLOW_ITEM_TYPE_VXLAN_GPE``, the struct ``rte_flow_item_vxlan_gpe``, its mask ``rte_flow_item_vxlan_gpe_mask``,
> +  and the header struct ``rte_vxlan_gpe_hdr`` with the macro ``RTE_ETHER_VXLAN_GPE_HLEN``
> +  will be removed in DPDK 25.11.

[...]
> @@ -38,8 +38,65 @@ struct rte_vxlan_hdr {
>  			rte_be32_t vx_vni;   /**< VNI (24) + Reserved (8). */
>  		};
>  		struct {
> -			uint8_t    flags;    /**< Should be 8 (I flag). */
> -			uint8_t    rsvd0[3]; /**< Reserved. */
> +			union {
> +				uint8_t    flags;    /**< Should be 8 (I flag). */
> +				/* Flag bits defined by GPE */
> +				struct {
> +#if RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN
> +					uint8_t flag_o:1,
> +						flag_b:1,
> +						flag_p:1,
> +						flag_i_gpe:1,
> +						flag_ver:2,
> +						rsvd_gpe:2;
> +#elif RTE_BYTE_ORDER == RTE_BIG_ENDIAN
> +					uint8_t rsvd_gpe:2,
> +						flag_ver:2,
> +						flag_i_gpe:1,
> +						flag_p:1,
> +						flag_b:1,
> +						flag_o:1;
> +#endif
> +				};
> +				/* Flag bits defined by GBP */
> +				struct {
> +#if RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN
> +					uint8_t rsvd_gbp1:3,
> +						flag_i_gbp:1,
> +						rsvd_gbp2:3,
> +						flag_g:1;
> +#elif RTE_BYTE_ORDER == RTE_BIG_ENDIAN
> +					uint8_t flag_g:1,
> +						rsvd_gbp1:3,
> +						flag_i_gbp:1,
> +						rsvd_gbp2:3;
> +#endif
> +				};
> +			};
> +			union {
> +				uint8_t    rsvd0[3]; /**< Reserved. */
> +				/* Overlap with rte_vxlan_gpe_hdr which is deprecated.*/
> +				struct {
> +					uint8_t rsvd0_gpe[2]; /**< Reserved. */
> +					uint8_t proto;	   /**< Next protocol. */
> +				};
> +				struct {
> +#if RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN
> +					uint8_t rsvd0_gbp1:3,
> +						policy_applied:1,
> +						rsvd0_gbp2:2,
> +						dont_learn:1,
> +						rsvd0_gbp3:1;
> +#elif RTE_BYTE_ORDER == RTE_BIG_ENDIAN
> +					uint8_t rsvd0_gbp1:1,
> +						dont_learn:1,
> +						rsvd0_gbp2:2,
> +						policy_applied:1,
> +						rsvd0_gbp3:3;
> +#endif
> +					uint16_t policy_id;
> +				};
> +			};
>  			uint8_t    vni[3];   /**< VXLAN identifier. */
>  			uint8_t    rsvd1;    /**< Reserved. */
>  		};

Naming looks OK.
Any different opinion?