IPv6: Complete IPV6_DONTFRAG support

Finally add support to detect a local IPV6_DONTFRAG event
and return the relevant data to the user if they've enabled
IPV6_RECVPATHMTU on the socket.  The next recvmsg() will
return no data, but have an IPV6_PATHMTU as ancillary data.

Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 1976942cf6f9..2ab5509f6d49 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -257,6 +257,7 @@ struct inet6_skb_parm {
 };
 
 #define IP6CB(skb)      ((struct inet6_skb_parm*)((skb)->cb))
+#define IP6CBMTU(skb)   ((struct ip6_mtuinfo *)((skb)->cb))
 
 static inline int inet6_iif(const struct sk_buff *skb)
 {
@@ -366,6 +367,7 @@ struct ipv6_pinfo {
 
         struct ipv6_txoptions   *opt;
         struct sk_buff          *pktoptions;
+        struct sk_buff          *rxpmtu;
         struct {
                 struct ipv6_txoptions *opt;
                 u8 hop_limit;
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 7ab6323e631e..eba5cc00325a 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -578,9 +578,11 @@ extern int			ip6_datagram_connect(struct sock *sk,
                                                      struct sockaddr *addr, int addr_len);
 
 extern int                      ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len);
+extern int                      ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len);
 extern void                     ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
                                                 u32 info, u8 *payload);
 extern void                     ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info);
+extern void                     ipv6_local_rxpmtu(struct sock *sk, struct flowi *fl, u32 mtu);
 
 extern int inet6_release(struct socket *sock);
 extern int inet6_bind(struct socket *sock, struct sockaddr *uaddr,