+static void ip6_append_data_mtu(unsigned int *mtu,
+ int *maxfraglen,
+ unsigned int fragheaderlen,
+ struct sk_buff *skb,
+ struct rt6_info *rt,
+ unsigned int orig_mtu)
+{
+ if (!(rt->dst.flags & DST_XFRM_TUNNEL)) {
+ if (skb == NULL) {
+ /* first fragment, reserve header_len */
+ *mtu = orig_mtu - rt->dst.header_len;
+
+ } else {
+ /*
+ * this fragment is not first, the headers
+ * space is regarded as data space.
+ */
+ *mtu = orig_mtu;
+ }
+ *maxfraglen = ((*mtu - fragheaderlen) & ~7)
+ + fragheaderlen - sizeof(struct frag_hdr);
+ }
+}
+