X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=lib%2Fodp-util.h;h=4020660b43998854214d289f8d66e1feed73ae75;hb=4f1046117c54e60b8ef6b7b21c23d3a4bf2e61fb;hp=074df87fbee232eac8b032631b35b505fe64d487;hpb=685a51a5b89750cead1b2934c2079d2bb9c52a4a;p=openvswitch diff --git a/lib/odp-util.h b/lib/odp-util.h index 074df87f..4020660b 100644 --- a/lib/odp-util.h +++ b/lib/odp-util.h @@ -63,14 +63,33 @@ void format_odp_action(struct ds *, const struct nlattr *); void format_odp_actions(struct ds *, const struct nlattr *odp_actions, size_t actions_len); -/* By my calculations currently the longest valid nlattr-formatted flow key is - * 124 bytes long, so this leaves some safety margin. +/* Upper bound on the length of a nlattr-formatted flow key. The longest + * nlattr-formatted flow key would be: * - * We allocate temporary on-stack buffers for flow keys as arrays of uint32_t + * struct pad nl hdr total + * ------ --- ------ ----- + * ODP_KEY_ATTR_TUN_ID 8 -- 4 12 + * ODP_KEY_ATTR_IN_PORT 4 -- 4 8 + * ODP_KEY_ATTR_ETHERNET 12 -- 4 16 + * ODP_KEY_ATTR_8021Q 4 -- 4 8 + * ODP_KEY_ATTR_ETHERTYPE 2 2 4 8 + * ODP_KEY_ATTR_IPV6 34 2 4 40 + * ODP_KEY_ATTR_ICMPV6 2 2 4 8 + * ODP_KEY_ATTR_ND 28 -- 4 32 + * ------------------------------------------------- + * total 132 + */ +#define ODPUTIL_FLOW_KEY_BYTES 132 + +/* This is an imperfect sanity-check that ODPUTIL_FLOW_KEY_BYTES doesn't + * need to be updated, but will at least raise awareness when new ODP + * key types are added. */ +BUILD_ASSERT_DECL(__ODP_KEY_ATTR_MAX == 14); + +/* We allocate temporary on-stack buffers for flow keys as arrays of uint32_t * to ensure proper 32-bit alignment for Netlink attributes. (An array of * "struct nlattr" might not, in theory, be sufficiently aligned because it * only contains 16-bit types.) */ -#define ODPUTIL_FLOW_KEY_BYTES 144 #define ODPUTIL_FLOW_KEY_U32S DIV_ROUND_UP(ODPUTIL_FLOW_KEY_BYTES, 4) void odp_flow_key_format(const struct nlattr *, size_t, struct ds *);