[SCTP] Mark chunks as ineligible for fast retransmit after they are

retransmitted. Also mark any chunks that could not be fit in the
PMTU sized packet as ineligible for fast retransmit.
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>

net/sctp/outqueue.c

@@ -525,10 +525,10 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
 			       int rtx_timeout, int *start_timer)
 {
 	struct list_head *lqueue;
-	struct list_head *lchunk;
+	struct list_head *lchunk, *lchunk1;
 	struct sctp_transport *transport = pkt->transport;
 	sctp_xmit_t status;
-	struct sctp_chunk *chunk;
+	struct sctp_chunk *chunk, *chunk1;
 	struct sctp_association *asoc;
 	int error = 0;
 
@@ -615,6 +615,12 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
 			 * the transmitted list.
 			 */
 			list_add_tail(lchunk, &transport->transmitted);
+
+			/* Mark the chunk as ineligible for fast retransmit 
+			 * after it is retransmitted.
+			 */
+			chunk->fast_retransmit = 0;
+
 			*start_timer = 1;
 			q->empty = 0;
 
@@ -622,6 +628,18 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
 			lchunk = sctp_list_dequeue(lqueue);
 			break;
 		};
+
+		/* If we are here due to a retransmit timeout or a fast
+		 * retransmit and if there are any chunks left in the retransmit
+		 * queue that could not fit in the PMTU sized packet, they need			 * to be marked as ineligible for a subsequent fast retransmit.
+		 */
+		if (rtx_timeout && !lchunk) {
+			list_for_each(lchunk1, lqueue) {
+				chunk1 = list_entry(lchunk1, struct sctp_chunk,
+						    transmitted_list);
+				chunk1->fast_retransmit = 0;
+			}
+		}
 	}
 
 	return error;