[SCTP] Update pmtu handling to be similar to tcp

[safe/jmp/linux-2.6] / net / sctp / transport.c

diff --git a/net/sctp/transport.c b/net/sctp/transport.c
index 05ab5e9..e14c271 100644 (file)
--- a/net/sctp/transport.c
+++ b/net/sctp/transport.c
@@ -62,7 +62,6 @@ static struct sctp_transport *sctp_transport_init(struct sctp_transport *peer,
 {
        /* Copy in the address.  */
        peer->ipaddr = *addr;
-       flip_to_h(&peer->ipaddr_h, &peer->ipaddr);
        peer->af_specific = sctp_get_af_specific(addr->sa.sa_family);
        peer->asoc = NULL;
 
@@ -131,9 +130,9 @@ static struct sctp_transport *sctp_transport_init(struct sctp_transport *peer,
 struct sctp_transport *sctp_transport_new(const union sctp_addr *addr,
                                          gfp_t gfp)
 {
-        struct sctp_transport *transport;
+       struct sctp_transport *transport;
 
-        transport = t_new(struct sctp_transport, gfp);
+       transport = t_new(struct sctp_transport, gfp);
        if (!transport)
                goto fail;
 
@@ -186,7 +185,7 @@ static void sctp_transport_destroy(struct sctp_transport *transport)
        if (transport->asoc)
                sctp_association_put(transport->asoc);
 
-        sctp_packet_free(&transport->packet);
+       sctp_packet_free(&transport->packet);
 
        dst_release(transport->dst);
        kfree(transport);
@@ -242,6 +241,47 @@ void sctp_transport_pmtu(struct sctp_transport *transport)
                transport->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
 }
 
+/* this is a complete rip-off from __sk_dst_check
+ * the cookie is always 0 since this is how it's used in the
+ * pmtu code
+ */
+static struct dst_entry *sctp_transport_dst_check(struct sctp_transport *t)
+{
+       struct dst_entry *dst = t->dst;
+
+       if (dst && dst->obsolete && dst->ops->check(dst, 0) == NULL) {
+               dst_release(t->dst);
+               t->dst = NULL;
+               return NULL;
+       }
+
+       return dst;
+}
+
+void sctp_transport_update_pmtu(struct sctp_transport *t, u32 pmtu)
+{
+       struct dst_entry *dst;
+
+       if (unlikely(pmtu < SCTP_DEFAULT_MINSEGMENT)) {
+               printk(KERN_WARNING "%s: Reported pmtu %d too low, "
+                      "using default minimum of %d\n",
+                      __FUNCTION__, pmtu,
+                      SCTP_DEFAULT_MINSEGMENT);
+               /* Use default minimum segment size and disable
+                * pmtu discovery on this transport.
+                */
+               t->pathmtu = SCTP_DEFAULT_MINSEGMENT;
+               t->param_flags = (t->param_flags & ~SPP_PMTUD) |
+                       SPP_PMTUD_DISABLE;
+       } else {
+               t->pathmtu = pmtu;
+       }
+
+       dst = sctp_transport_dst_check(t);
+       if (dst)
+               dst->ops->update_pmtu(dst, pmtu);
+}
+
 /* Caches the dst entry and source address for a transport's destination
  * address.
  */
@@ -269,7 +309,7 @@ void sctp_transport_route(struct sctp_transport *transport,
 
                /* Initialize sk->sk_rcv_saddr, if the transport is the
                 * association's active path for getsockname().
-                */ 
+                */
                if (asoc && (transport == asoc->peer.active_path))
                        opt->pf->af->to_sk_saddr(&transport->saddr,
                                                 asoc->base.sk);
@@ -460,8 +500,8 @@ void sctp_transport_lower_cwnd(struct sctp_transport *transport,
                 * destination address(es) to which the missing DATA chunks
                 * were last sent, according to the formula described in
                 * Section 7.2.3.
-                *
-                * RFC 2960 7.2.3, sctpimpguide Upon detection of packet
+                *
+                * RFC 2960 7.2.3, sctpimpguide Upon detection of packet
                 * losses from SACK (see Section 7.2.4), An endpoint
                 * should do the following:
                 *      ssthresh = max(cwnd/2, 4*MTU)
@@ -489,7 +529,7 @@ void sctp_transport_lower_cwnd(struct sctp_transport *transport,
                if ((jiffies - transport->last_time_ecne_reduced) >
                    transport->rtt) {
                        transport->ssthresh = max(transport->cwnd/2,
-                                                 4*transport->asoc->pathmtu);
+                                                 4*transport->asoc->pathmtu);
                        transport->cwnd = transport->ssthresh;
                        transport->last_time_ecne_reduced = jiffies;
                }
@@ -508,7 +548,7 @@ void sctp_transport_lower_cwnd(struct sctp_transport *transport,
                        transport->cwnd = max(transport->cwnd/2,
                                                 4*transport->asoc->pathmtu);
                break;
-       };
+       }
 
        transport->partial_bytes_acked = 0;
        SCTP_DEBUG_PRINTK("%s: transport: %p reason: %d cwnd: "
@@ -527,3 +567,35 @@ unsigned long sctp_transport_timeout(struct sctp_transport *t)
        timeout += jiffies;
        return timeout;
 }
+
+/* Reset transport variables to their initial values */
+void sctp_transport_reset(struct sctp_transport *t)
+{
+       struct sctp_association *asoc = t->asoc;
+
+       /* RFC 2960 (bis), Section 5.2.4
+        * All the congestion control parameters (e.g., cwnd, ssthresh)
+        * related to this peer MUST be reset to their initial values
+        * (see Section 6.2.1)
+        */
+       t->cwnd = min(4*asoc->pathmtu, max_t(__u32, 2*asoc->pathmtu, 4380));
+       t->ssthresh = asoc->peer.i.a_rwnd;
+       t->rto = asoc->rto_initial;
+       t->rtt = 0;
+       t->srtt = 0;
+       t->rttvar = 0;
+
+       /* Reset these additional varibles so that we have a clean
+        * slate.
+        */
+       t->partial_bytes_acked = 0;
+       t->flight_size = 0;
+       t->error_count = 0;
+       t->rto_pending = 0;
+
+       /* Initialize the state information for SFR-CACC */
+       t->cacc.changeover_active = 0;
+       t->cacc.cycling_changeover = 0;
+       t->cacc.next_tsn_at_change = 0;
+       t->cacc.cacc_saw_newack = 0;
+}