ipv4: Add helper inet_csk_update_pmtu().
This abstracts away the call to dst_ops->update_pmtu() so that we can
transparently handle the fact that, in the future, the dst itself can
be invalidated by the PMTU update (when we have non-host routes cached
in sockets).
So we try to rebuild the socket cached route after the method
invocation if necessary.
This isn't used by SCTP because it needs to cache dsts per-transport,
and thus will need it's own local version of this helper.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h
index 291e7ce..2cf44b4e 100644
--- a/include/net/inet_connection_sock.h
+++ b/include/net/inet_connection_sock.h
@@ -337,4 +337,6 @@
char __user *optval, int __user *optlen);
extern int inet_csk_compat_setsockopt(struct sock *sk, int level, int optname,
char __user *optval, unsigned int optlen);
+
+extern struct dst_entry *inet_csk_update_pmtu(struct sock *sk, u32 mtu);
#endif /* _INET_CONNECTION_SOCK_H */