-
-static inline unsigned int ipv6_advmss(unsigned int mtu)
-{
- mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr);
-
- if (mtu < ip6_rt_min_advmss)
- mtu = ip6_rt_min_advmss;
-
- /*
- * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and
- * corresponding MSS is IPV6_MAXPLEN - tcp_header_size.
- * IPV6_MAXPLEN is also valid and means: "any MSS,
- * rely only on pmtu discovery"
- */
- if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr))
- mtu = IPV6_MAXPLEN;
- return mtu;
-}