1 files changed, 80 insertions, 13 deletions

diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 525864bf4f07..8450960df24f 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -112,6 +112,7 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a
         asoc->cookie_life.tv_usec = (sp->assocparams.sasoc_cookie_life % 1000)
                                         * 1000;
         asoc->frag_point = 0;
+        asoc->user_frag = sp->user_frag;
 
         /* Set the association max_retrans and RTO values from the
          * socket values.
@@ -202,6 +203,7 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a
         asoc->a_rwnd = asoc->rwnd;
 
         asoc->rwnd_over = 0;
+        asoc->rwnd_press = 0;
 
         /* Use my own max window until I learn something better.  */
         asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW;
@@ -582,6 +584,33 @@ void sctp_assoc_rm_peer(struct sctp_association *asoc,
             asoc->addip_last_asconf->transport == peer)
                 asoc->addip_last_asconf->transport = NULL;
 
+        /* If we have something on the transmitted list, we have to
+         * save it off.  The best place is the active path.
+         */
+        if (!list_empty(&peer->transmitted)) {
+                struct sctp_transport *active = asoc->peer.active_path;
+                struct sctp_chunk *ch;
+
+                /* Reset the transport of each chunk on this list */
+                list_for_each_entry(ch, &peer->transmitted,
+                                        transmitted_list) {
+                        ch->transport = NULL;
+                        ch->rtt_in_progress = 0;
+                }
+
+                list_splice_tail_init(&peer->transmitted,
+                                        &active->transmitted);
+
+                /* Start a T3 timer here in case it wasn't running so
+                 * that these migrated packets have a chance to get
+                 * retrnasmitted.
+                 */
+                if (!timer_pending(&active->T3_rtx_timer))
+                        if (!mod_timer(&active->T3_rtx_timer,
+                                        jiffies + active->rto))
+                                sctp_transport_hold(active);
+        }
+
         asoc->peer.transport_count--;
 
         sctp_transport_free(peer);
@@ -651,13 +680,15 @@ struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
          */
         peer->param_flags = asoc->param_flags;
 
+        sctp_transport_route(peer, NULL, sp);
+
         /* Initialize the pmtu of the transport. */
-        if (peer->param_flags & SPP_PMTUD_ENABLE)
-                sctp_transport_pmtu(peer);
-        else if (asoc->pathmtu)
-                peer->pathmtu = asoc->pathmtu;
-        else
-                peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
+        if (peer->param_flags & SPP_PMTUD_DISABLE) {
+                if (asoc->pathmtu)
+                        peer->pathmtu = asoc->pathmtu;
+                else
+                        peer->pathmtu = SCTP_DEFAULT_MAXSEGMENT;
+        }
 
         /* If this is the first transport addr on this association,
          * initialize the association PMTU to the peer's PMTU.
@@ -673,7 +704,7 @@ struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
                           "%d\n", asoc, asoc->pathmtu);
         peer->pmtu_pending = 0;
 
-        asoc->frag_point = sctp_frag_point(sp, asoc->pathmtu);
+        asoc->frag_point = sctp_frag_point(asoc, asoc->pathmtu);
 
         /* The asoc->peer.port might not be meaningful yet, but
          * initialize the packet structure anyway.
@@ -810,11 +841,16 @@ void sctp_assoc_control_transport(struct sctp_association *asoc,
                 break;
 
         case SCTP_TRANSPORT_DOWN:
-                /* if the transort was never confirmed, do not transition it
-                 * to inactive state.
+                /* If the transport was never confirmed, do not transition it
+                 * to inactive state.  Also, release the cached route since
+                 * there may be a better route next time.
                  */
                 if (transport->state != SCTP_UNCONFIRMED)
                         transport->state = SCTP_INACTIVE;
+                else {
+                        dst_release(transport->dst);
+                        transport->dst = NULL;
+                }
 
                 spc_state = SCTP_ADDR_UNREACHABLE;
                 break;
@@ -1324,9 +1360,8 @@ void sctp_assoc_sync_pmtu(struct sctp_association *asoc)
         }
 
         if (pmtu) {
-                struct sctp_sock *sp = sctp_sk(asoc->base.sk);
                 asoc->pathmtu = pmtu;
-                asoc->frag_point = sctp_frag_point(sp, pmtu);
+                asoc->frag_point = sctp_frag_point(asoc, pmtu);
         }
 
         SCTP_DEBUG_PRINTK("%s: asoc:%p, pmtu:%d, frag_point:%d\n",
@@ -1369,6 +1404,17 @@ void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned len)
                 asoc->rwnd += len;
         }
 
+        /* If we had window pressure, start recovering it
+         * once our rwnd had reached the accumulated pressure
+         * threshold.  The idea is to recover slowly, but up
+         * to the initial advertised window.
+         */
+        if (asoc->rwnd_press && asoc->rwnd >= asoc->rwnd_press) {
+                int change = min(asoc->pathmtu, asoc->rwnd_press);
+                asoc->rwnd += change;
+                asoc->rwnd_press -= change;
+        }
+
         SCTP_DEBUG_PRINTK("%s: asoc %p rwnd increased by %d to (%u, %u) "
                           "- %u\n", __func__, asoc, len, asoc->rwnd,
                           asoc->rwnd_over, asoc->a_rwnd);
@@ -1401,17 +1447,38 @@ void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned len)
 /* Decrease asoc's rwnd by len. */
 void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned len)
 {
+        int rx_count;
+        int over = 0;
+
         SCTP_ASSERT(asoc->rwnd, "rwnd zero", return);
         SCTP_ASSERT(!asoc->rwnd_over, "rwnd_over not zero", return);
+
+        if (asoc->ep->rcvbuf_policy)
+                rx_count = atomic_read(&asoc->rmem_alloc);
+        else
+                rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
+
+        /* If we've reached or overflowed our receive buffer, announce
+         * a 0 rwnd if rwnd would still be positive.  Store the
+         * the pottential pressure overflow so that the window can be restored
+         * back to original value.
+         */
+        if (rx_count >= asoc->base.sk->sk_rcvbuf)
+                over = 1;
+
         if (asoc->rwnd >= len) {
                 asoc->rwnd -= len;
+                if (over) {
+                        asoc->rwnd_press = asoc->rwnd;
+                        asoc->rwnd = 0;
+                }
         } else {
                 asoc->rwnd_over = len - asoc->rwnd;
                 asoc->rwnd = 0;
         }
-        SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u)\n",
+        SCTP_DEBUG_PRINTK("%s: asoc %p rwnd decreased by %d to (%u, %u, %u)\n",
                           __func__, asoc, len, asoc->rwnd,
-                          asoc->rwnd_over);
+                          asoc->rwnd_over, asoc->rwnd_press);
 }
 
 /* Build the bind address list for the association based on info from the