[SCTP] Bundle SACK with outgoing DATA.

If we are sending DATA, bundle a SACK.  Otherwise, we end up 
always waiting for the delayed SACK rules (timer or every other
packet rule) to kick in.   

2 files changed, 18 insertions, 6 deletions

diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index 27a69518c2f9..7ad60bcd5581 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -123,7 +123,7 @@
  */
 extern struct sctp_protocol sctp_proto;
 extern struct sock *sctp_get_ctl_sock(void);
-extern int sctp_copy_local_addr_list(struct sctp_protocol  *, 
+extern int sctp_copy_local_addr_list(struct sctp_protocol  *,
 				     struct sctp_bind_addr *,
 				     sctp_scope_t, int priority, int flags);
 extern struct sctp_pf *sctp_get_pf_specific(sa_family_t family);
@@ -414,13 +414,22 @@ static inline __s32 sctp_jitter(__u32 rto)
 	sctp_rand ^= (sctp_rand << 12);
 	sctp_rand ^= (sctp_rand >> 20);
 
-	/* Choose random number from 0 to rto, then move to -50% ~ +50% 
-	 * of rto. 
+	/* Choose random number from 0 to rto, then move to -50% ~ +50%
+	 * of rto.
 	 */
 	ret = sctp_rand % rto - (rto >> 1);
 	return ret;
 }
 
+/* Break down data chunks at this point.  */
+static inline int sctp_frag_point(int pmtu)
+{
+	pmtu -= SCTP_IP_OVERHEAD + sizeof(struct sctp_data_chunk);
+	pmtu -= sizeof(struct sctp_sack_chunk);
+
+	return pmtu;
+}
+
 /* Walk through a list of TLV parameters.  Don't trust the
  * individual parameter lengths and instead depend on
  * the chunk length to indicate when to stop.  Make sure
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 913c4769b343..e22b333a94b2 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -590,13 +590,16 @@ struct sctp_packet {
 	/* This packet should advertise ECN capability to the network
 	 * via the ECT bit.
 	 */
-	int ecn_capable;
+	char ecn_capable;
 
 	/* This packet contains a COOKIE-ECHO chunk. */
-	int has_cookie_echo;
+	char has_cookie_echo;
+
+	/* This packet containsa SACK chunk. */
+	char has_sack; 
 
 	/* SCTP cannot fragment this packet. So let ip fragment it. */
-	int ipfragok;
+	char ipfragok;
 
 	int malloced;
 };