[ovs-dev] [PATCH net-next V2 1/1] openvswitch: Declare ovs key structures using macros

[Gregory Rose]

On 2/3/2019 1:12 AM, Eli Britstein wrote:
> Declare ovs key structures using macros as a pre-step towards to
> enable retrieving fields information, as a work done in proposed
> commit in the OVS tree https://patchwork.ozlabs.org/patch/1023406/
> ("odp-util: Do not rewrite fields with the same values as matched"),
> with no functional change.
>
> Signed-off-by: Eli Britstein <elibr at mellanox.com>
> Reviewed-by: Roi Dayan <roid at mellanox.com>

Obscuring the structures with these macros is awful.  I'm opposed but I 
see it has already been
accepted upstream so I guess that's that.

Ugh...

- Greg

> ---
>   include/uapi/linux/openvswitch.h | 102 ++++++++++++++++++++++++++-------------
>   1 file changed, 69 insertions(+), 33 deletions(-)
>
> diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h
> index dbe0cbe4f1b7..dc8246f871fd 100644
> --- a/include/uapi/linux/openvswitch.h
> +++ b/include/uapi/linux/openvswitch.h
> @@ -387,73 +387,109 @@ enum ovs_frag_type {
>   
>   #define OVS_FRAG_TYPE_MAX (__OVS_FRAG_TYPE_MAX - 1)
>   
> +#define OVS_KEY_FIELD_ARR(type, name, elements) type name[elements];
> +#define OVS_KEY_FIELD(type, name) type name;
> +
> +#define OVS_KEY_ETHERNET_FIELDS \
> +    OVS_KEY_FIELD_ARR(__u8, eth_src, ETH_ALEN) \
> +    OVS_KEY_FIELD_ARR(__u8, eth_dst, ETH_ALEN)
> +
>   struct ovs_key_ethernet {
> -	__u8	 eth_src[ETH_ALEN];
> -	__u8	 eth_dst[ETH_ALEN];
> +    OVS_KEY_ETHERNET_FIELDS
>   };
>   
>   struct ovs_key_mpls {
>   	__be32 mpls_lse;
>   };
>   
> +#define OVS_KEY_IPV4_FIELDS \
> +    OVS_KEY_FIELD(__be32, ipv4_src) \
> +    OVS_KEY_FIELD(__be32, ipv4_dst) \
> +    OVS_KEY_FIELD(__u8, ipv4_proto) \
> +    OVS_KEY_FIELD(__u8, ipv4_tos) \
> +    OVS_KEY_FIELD(__u8, ipv4_ttl) \
> +    OVS_KEY_FIELD(__u8, ipv4_frag /* One of OVS_FRAG_TYPE_*. */)
> +
>   struct ovs_key_ipv4 {
> -	__be32 ipv4_src;
> -	__be32 ipv4_dst;
> -	__u8   ipv4_proto;
> -	__u8   ipv4_tos;
> -	__u8   ipv4_ttl;
> -	__u8   ipv4_frag;	/* One of OVS_FRAG_TYPE_*. */
> +    OVS_KEY_IPV4_FIELDS
>   };
>   
> +#define OVS_KEY_IPV6_FIELDS \
> +    OVS_KEY_FIELD_ARR(__be32, ipv6_src, 4) \
> +    OVS_KEY_FIELD_ARR(__be32, ipv6_dst, 4) \
> +    OVS_KEY_FIELD(__be32, ipv6_label /* 20-bits in least-significant bits. */) \
> +    OVS_KEY_FIELD(__u8, ipv6_proto) \
> +    OVS_KEY_FIELD(__u8, ipv6_tclass) \
> +    OVS_KEY_FIELD(__u8, ipv6_hlimit) \
> +    OVS_KEY_FIELD(__u8, ipv6_frag /* One of OVS_FRAG_TYPE_*. */)
> +
>   struct ovs_key_ipv6 {
> -	__be32 ipv6_src[4];
> -	__be32 ipv6_dst[4];
> -	__be32 ipv6_label;	/* 20-bits in least-significant bits. */
> -	__u8   ipv6_proto;
> -	__u8   ipv6_tclass;
> -	__u8   ipv6_hlimit;
> -	__u8   ipv6_frag;	/* One of OVS_FRAG_TYPE_*. */
> +    OVS_KEY_IPV6_FIELDS
>   };
>   
> +#define OVS_KEY_TCP_FIELDS \
> +    OVS_KEY_FIELD(__be16, tcp_src) \
> +    OVS_KEY_FIELD(__be16, tcp_dst)
> +
>   struct ovs_key_tcp {
> -	__be16 tcp_src;
> -	__be16 tcp_dst;
> +    OVS_KEY_TCP_FIELDS
>   };
>   
> +#define OVS_KEY_UDP_FIELDS \
> +    OVS_KEY_FIELD(__be16, udp_src) \
> +    OVS_KEY_FIELD(__be16, udp_dst)
> +
>   struct ovs_key_udp {
> -	__be16 udp_src;
> -	__be16 udp_dst;
> +    OVS_KEY_UDP_FIELDS
>   };
>   
> +#define OVS_KEY_SCTP_FIELDS \
> +    OVS_KEY_FIELD(__be16, sctp_src) \
> +    OVS_KEY_FIELD(__be16, sctp_dst)
> +
>   struct ovs_key_sctp {
> -	__be16 sctp_src;
> -	__be16 sctp_dst;
> +    OVS_KEY_SCTP_FIELDS
>   };
>   
> +#define OVS_KEY_ICMP_FIELDS \
> +    OVS_KEY_FIELD(__u8, icmp_type) \
> +    OVS_KEY_FIELD(__u8, icmp_code)
> +
>   struct ovs_key_icmp {
> -	__u8 icmp_type;
> -	__u8 icmp_code;
> +    OVS_KEY_ICMP_FIELDS
>   };
>   
> +#define OVS_KEY_ICMPV6_FIELDS \
> +    OVS_KEY_FIELD(__u8, icmpv6_type) \
> +    OVS_KEY_FIELD(__u8, icmpv6_code)
> +
>   struct ovs_key_icmpv6 {
> -	__u8 icmpv6_type;
> -	__u8 icmpv6_code;
> +    OVS_KEY_ICMPV6_FIELDS
>   };
>   
> +#define OVS_KEY_ARP_FIELDS \
> +    OVS_KEY_FIELD(__be32, arp_sip) \
> +    OVS_KEY_FIELD(__be32, arp_tip) \
> +    OVS_KEY_FIELD(__be16, arp_op) \
> +    OVS_KEY_FIELD_ARR(__u8, arp_sha, ETH_ALEN) \
> +    OVS_KEY_FIELD_ARR(__u8, arp_tha, ETH_ALEN)
> +
>   struct ovs_key_arp {
> -	__be32 arp_sip;
> -	__be32 arp_tip;
> -	__be16 arp_op;
> -	__u8   arp_sha[ETH_ALEN];
> -	__u8   arp_tha[ETH_ALEN];
> +    OVS_KEY_ARP_FIELDS
>   };
>   
> +#define OVS_KEY_ND_FIELDS \
> +    OVS_KEY_FIELD_ARR(__be32, nd_target, 4) \
> +    OVS_KEY_FIELD_ARR(__u8, nd_sll, ETH_ALEN) \
> +    OVS_KEY_FIELD_ARR(__u8, nd_tll, ETH_ALEN)
> +
>   struct ovs_key_nd {
> -	__be32	nd_target[4];
> -	__u8	nd_sll[ETH_ALEN];
> -	__u8	nd_tll[ETH_ALEN];
> +    OVS_KEY_ND_FIELDS
>   };
>   
> +#undef OVS_KEY_FIELD_ARR
> +#undef OVS_KEY_FIELD
> +
>   #define OVS_CT_LABELS_LEN_32	4
>   #define OVS_CT_LABELS_LEN	(OVS_CT_LABELS_LEN_32 * sizeof(__u32))
>   struct ovs_key_ct_labels {