Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6
[safe/jmp/linux-2.6] / net / sctp / outqueue.c
index e315c6c..23e5e97 100644 (file)
@@ -1,21 +1,21 @@
-/* SCTP kernel reference Implementation
+/* SCTP kernel implementation
  * (C) Copyright IBM Corp. 2001, 2004
  * Copyright (c) 1999-2000 Cisco, Inc.
  * Copyright (c) 1999-2001 Motorola, Inc.
  * Copyright (c) 2001-2003 Intel Corp.
  *
- * This file is part of the SCTP kernel reference Implementation
+ * This file is part of the SCTP kernel implementation
  *
  * These functions implement the sctp_outq class.   The outqueue handles
  * bundling and queueing of outgoing SCTP chunks.
  *
- * The SCTP reference implementation is free software;
+ * This SCTP implementation is free software;
  * you can redistribute it and/or modify it under the terms of
  * the GNU General Public License as published by
  * the Free Software Foundation; either version 2, or (at your option)
  * any later version.
  *
- * The SCTP reference implementation is distributed in the hope that it
+ * This SCTP implementation is distributed in the hope that it
  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  *                 ************************
  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
@@ -71,6 +71,8 @@ static void sctp_mark_missing(struct sctp_outq *q,
 
 static void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 sack_ctsn);
 
+static int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout);
+
 /* Add data to the front of the queue. */
 static inline void sctp_outq_head_data(struct sctp_outq *q,
                                        struct sctp_chunk *ch)
@@ -208,6 +210,7 @@ void sctp_outq_init(struct sctp_association *asoc, struct sctp_outq *q)
        INIT_LIST_HEAD(&q->sacked);
        INIT_LIST_HEAD(&q->abandoned);
 
+       q->fast_rtx = 0;
        q->outstanding_bytes = 0;
        q->empty = 1;
        q->cork  = 0;
@@ -221,12 +224,12 @@ void sctp_outq_init(struct sctp_association *asoc, struct sctp_outq *q)
 void sctp_outq_teardown(struct sctp_outq *q)
 {
        struct sctp_transport *transport;
-       struct list_head *lchunk, *pos, *temp;
+       struct list_head *lchunk, *temp;
        struct sctp_chunk *chunk, *tmp;
 
        /* Throw away unacknowledged chunks. */
-       list_for_each(pos, &q->asoc->peer.transport_addr_list) {
-               transport = list_entry(pos, struct sctp_transport, transports);
+       list_for_each_entry(transport, &q->asoc->peer.transport_addr_list,
+                       transports) {
                while ((lchunk = sctp_list_dequeue(&transport->transmitted)) != NULL) {
                        chunk = list_entry(lchunk, struct sctp_chunk,
                                           transmitted_list);
@@ -382,7 +385,7 @@ static void sctp_insert_list(struct list_head *head, struct list_head *new)
 /* Mark all the eligible packets on a transport for retransmission.  */
 void sctp_retransmit_mark(struct sctp_outq *q,
                          struct sctp_transport *transport,
-                         __u8 fast_retransmit)
+                         __u8 reason)
 {
        struct list_head *lchunk, *ltemp;
        struct sctp_chunk *chunk;
@@ -403,8 +406,9 @@ void sctp_retransmit_mark(struct sctp_outq *q,
                         * not be retransmitted
                         */
                        if (!chunk->tsn_gap_acked) {
-                               chunk->transport->flight_size -=
-                                               sctp_data_size(chunk);
+                               if (chunk->transport)
+                                       chunk->transport->flight_size -=
+                                                       sctp_data_size(chunk);
                                q->outstanding_bytes -= sctp_data_size(chunk);
                                q->asoc->peer.rwnd += (sctp_data_size(chunk) +
                                                        sizeof(struct sk_buff));
@@ -412,22 +416,13 @@ void sctp_retransmit_mark(struct sctp_outq *q,
                        continue;
                }
 
-               /* If we are doing retransmission due to a fast retransmit,
-                * only the chunk's that are marked for fast retransmit
-                * should be added to the retransmit queue.  If we are doing
-                * retransmission due to a timeout or pmtu discovery, only the
-                * chunks that are not yet acked should be added to the
-                * retransmit queue.
+               /* If we are doing  retransmission due to a timeout or pmtu
+                * discovery, only the  chunks that are not yet acked should
+                * be added to the retransmit queue.
                 */
-               if ((fast_retransmit && (chunk->fast_retransmit > 0)) ||
-                  (!fast_retransmit && !chunk->tsn_gap_acked)) {
-                       /* If this chunk was sent less then 1 rto ago, do not
-                        * retransmit this chunk, but give the peer time
-                        * to acknowlege it.
-                        */
-                       if ((jiffies - chunk->sent_at) < transport->rto)
-                               continue;
-
+               if ((reason == SCTP_RTXR_FAST_RTX  &&
+                           (chunk->fast_retransmit == SCTP_NEED_FRTX)) ||
+                   (reason != SCTP_RTXR_FAST_RTX  && !chunk->tsn_gap_acked)) {
                        /* RFC 2960 6.2.1 Processing a Received SACK
                         *
                         * C) Any time a DATA chunk is marked for
@@ -439,7 +434,8 @@ void sctp_retransmit_mark(struct sctp_outq *q,
                        q->asoc->peer.rwnd += (sctp_data_size(chunk) +
                                                sizeof(struct sk_buff));
                        q->outstanding_bytes -= sctp_data_size(chunk);
-                       transport->flight_size -= sctp_data_size(chunk);
+                       if (chunk->transport)
+                               transport->flight_size -= sctp_data_size(chunk);
 
                        /* sctpimpguide-05 Section 2.8.2
                         * M5) If a T3-rtx timer expires, the
@@ -467,10 +463,10 @@ void sctp_retransmit_mark(struct sctp_outq *q,
                }
        }
 
-       SCTP_DEBUG_PRINTK("%s: transport: %p, fast_retransmit: %d, "
+       SCTP_DEBUG_PRINTK("%s: transport: %p, reason: %d, "
                          "cwnd: %d, ssthresh: %d, flight_size: %d, "
-                         "pba: %d\n", __FUNCTION__,
-                         transport, fast_retransmit,
+                         "pba: %d\n", __func__,
+                         transport, reason,
                          transport->cwnd, transport->ssthresh,
                          transport->flight_size,
                          transport->partial_bytes_acked);
@@ -484,7 +480,6 @@ void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport,
                     sctp_retransmit_reason_t reason)
 {
        int error = 0;
-       __u8 fast_retransmit = 0;
 
        switch(reason) {
        case SCTP_RTXR_T3_RTX:
@@ -495,28 +490,40 @@ void sctp_retransmit(struct sctp_outq *q, struct sctp_transport *transport,
                 */
                if (transport == transport->asoc->peer.retran_path)
                        sctp_assoc_update_retran_path(transport->asoc);
+               transport->asoc->rtx_data_chunks +=
+                       transport->asoc->unack_data;
                break;
        case SCTP_RTXR_FAST_RTX:
                SCTP_INC_STATS(SCTP_MIB_FAST_RETRANSMITS);
                sctp_transport_lower_cwnd(transport, SCTP_LOWER_CWND_FAST_RTX);
-               fast_retransmit = 1;
+               q->fast_rtx = 1;
                break;
        case SCTP_RTXR_PMTUD:
                SCTP_INC_STATS(SCTP_MIB_PMTUD_RETRANSMITS);
                break;
+       case SCTP_RTXR_T1_RTX:
+               SCTP_INC_STATS(SCTP_MIB_T1_RETRANSMITS);
+               transport->asoc->init_retries++;
+               break;
        default:
                BUG();
        }
 
-       sctp_retransmit_mark(q, transport, fast_retransmit);
+       sctp_retransmit_mark(q, transport, reason);
 
        /* PR-SCTP A5) Any time the T3-rtx timer expires, on any destination,
         * the sender SHOULD try to advance the "Advanced.Peer.Ack.Point" by
         * following the procedures outlined in C1 - C5.
         */
-       sctp_generate_fwdtsn(q, q->asoc->ctsn_ack_point);
+       if (reason == SCTP_RTXR_T3_RTX)
+               sctp_generate_fwdtsn(q, q->asoc->ctsn_ack_point);
 
-       error = sctp_outq_flush(q, /* rtx_timeout */ 1);
+       /* Flush the queues only on timeout, since fast_rtx is only
+        * triggered during sack processing and the queue
+        * will be flushed at the end.
+        */
+       if (reason != SCTP_RTXR_FAST_RTX)
+               error = sctp_outq_flush(q, /* rtx_timeout */ 1);
 
        if (error)
                q->asoc->base.sk->sk_err = -error;
@@ -534,17 +541,23 @@ 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, *lchunk1;
        struct sctp_transport *transport = pkt->transport;
        sctp_xmit_t status;
        struct sctp_chunk *chunk, *chunk1;
        struct sctp_association *asoc;
+       int fast_rtx;
        int error = 0;
+       int timer = 0;
+       int done = 0;
 
        asoc = q->asoc;
        lqueue = &q->retransmit;
+       fast_rtx = q->fast_rtx;
 
-       /* RFC 2960 6.3.3 Handle T3-rtx Expiration
+       /* This loop handles time-out retransmissions, fast retransmissions,
+        * and retransmissions due to opening of whindow.
+        *
+        * RFC 2960 6.3.3 Handle T3-rtx Expiration
         *
         * E3) Determine how many of the earliest (i.e., lowest TSN)
         * outstanding DATA chunks for the address for which the
@@ -559,12 +572,12 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
         * [Just to be painfully clear, if we are retransmitting
         * because a timeout just happened, we should send only ONE
         * packet of retransmitted data.]
+        *
+        * For fast retransmissions we also send only ONE packet.  However,
+        * if we are just flushing the queue due to open window, we'll
+        * try to send as much as possible.
         */
-       lchunk = sctp_list_dequeue(lqueue);
-
-       while (lchunk) {
-               chunk = list_entry(lchunk, struct sctp_chunk,
-                                  transmitted_list);
+       list_for_each_entry_safe(chunk, chunk1, lqueue, transmitted_list) {
 
                /* Make sure that Gap Acked TSNs are not retransmitted.  A
                 * simple approach is just to move such TSNs out of the
@@ -572,88 +585,105 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
                 * next chunk.
                 */
                if (chunk->tsn_gap_acked) {
-                       list_add_tail(lchunk, &transport->transmitted);
-                       lchunk = sctp_list_dequeue(lqueue);
+                       list_del(&chunk->transmitted_list);
+                       list_add_tail(&chunk->transmitted_list,
+                                       &transport->transmitted);
                        continue;
                }
 
+               /* If we are doing fast retransmit, ignore non-fast_rtransmit
+                * chunks
+                */
+               if (fast_rtx && !chunk->fast_retransmit)
+                       continue;
+
                /* Attempt to append this chunk to the packet. */
                status = sctp_packet_append_chunk(pkt, chunk);
 
                switch (status) {
                case SCTP_XMIT_PMTU_FULL:
                        /* Send this packet.  */
-                       if ((error = sctp_packet_transmit(pkt)) == 0)
-                               *start_timer = 1;
+                       error = sctp_packet_transmit(pkt);
 
                        /* If we are retransmitting, we should only
                         * send a single packet.
                         */
-                       if (rtx_timeout) {
-                               list_add(lchunk, lqueue);
-                               lchunk = NULL;
-                       }
+                       if (rtx_timeout || fast_rtx)
+                               done = 1;
 
-                       /* Bundle lchunk in the next round.  */
+                       /* Bundle next chunk in the next round.  */
                        break;
 
                case SCTP_XMIT_RWND_FULL:
                        /* Send this packet. */
-                       if ((error = sctp_packet_transmit(pkt)) == 0)
-                               *start_timer = 1;
+                       error = sctp_packet_transmit(pkt);
 
                        /* Stop sending DATA as there is no more room
                         * at the receiver.
                         */
-                       list_add(lchunk, lqueue);
-                       lchunk = NULL;
+                       done = 1;
                        break;
 
                case SCTP_XMIT_NAGLE_DELAY:
                        /* Send this packet. */
-                       if ((error = sctp_packet_transmit(pkt)) == 0)
-                               *start_timer = 1;
+                       error = sctp_packet_transmit(pkt);
 
                        /* Stop sending DATA because of nagle delay. */
-                       list_add(lchunk, lqueue);
-                       lchunk = NULL;
+                       done = 1;
                        break;
 
                default:
                        /* The append was successful, so add this chunk to
                         * the transmitted list.
                         */
-                       list_add_tail(lchunk, &transport->transmitted);
+                       list_del(&chunk->transmitted_list);
+                       list_add_tail(&chunk->transmitted_list,
+                                       &transport->transmitted);
 
                        /* Mark the chunk as ineligible for fast retransmit
                         * after it is retransmitted.
                         */
-                       if (chunk->fast_retransmit > 0)
-                               chunk->fast_retransmit = -1;
+                       if (chunk->fast_retransmit == SCTP_NEED_FRTX)
+                               chunk->fast_retransmit = SCTP_DONT_FRTX;
 
-                       *start_timer = 1;
-                       q->empty = 0;
+                       /* Force start T3-rtx timer when fast retransmitting
+                        * the earliest outstanding TSN
+                        */
+                       if (!timer && fast_rtx &&
+                           ntohl(chunk->subh.data_hdr->tsn) ==
+                                            asoc->ctsn_ack_point + 1)
+                               timer = 2;
 
-                       /* Retrieve a new chunk to bundle. */
-                       lchunk = sctp_list_dequeue(lqueue);
+                       q->empty = 0;
                        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);
-                               if (chunk1->fast_retransmit > 0)
-                                       chunk1->fast_retransmit = -1;
-                       }
+               /* Set the timer if there were no errors */
+               if (!error && !timer)
+                       timer = 1;
+
+               if (done)
+                       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 || fast_rtx) {
+               list_for_each_entry(chunk1, lqueue, transmitted_list) {
+                       if (chunk1->fast_retransmit == SCTP_NEED_FRTX)
+                               chunk1->fast_retransmit = SCTP_DONT_FRTX;
                }
        }
 
+       *start_timer = timer;
+
+       /* Clear fast retransmit hint */
+       if (fast_rtx)
+               q->fast_rtx = 0;
+
        return error;
 }
 
@@ -661,13 +691,13 @@ static int sctp_outq_flush_rtx(struct sctp_outq *q, struct sctp_packet *pkt,
 int sctp_outq_uncork(struct sctp_outq *q)
 {
        int error = 0;
-       if (q->cork) {
+       if (q->cork)
                q->cork = 0;
-               error = sctp_outq_flush(q, 0);
-       }
+       error = sctp_outq_flush(q, 0);
        return error;
 }
 
+
 /*
  * Try to flush an outqueue.
  *
@@ -677,7 +707,7 @@ int sctp_outq_uncork(struct sctp_outq *q)
  * locking concerns must be made.  Today we use the sock lock to protect
  * this function.
  */
-int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
+static int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
 {
        struct sctp_packet *packet;
        struct sctp_packet singleton;
@@ -691,6 +721,7 @@ int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
        sctp_xmit_t status;
        int error = 0;
        int start_timer = 0;
+       int one_packet = 0;
 
        /* These transports have chunks to send. */
        struct list_head transport_list;
@@ -716,7 +747,29 @@ int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
                new_transport = chunk->transport;
 
                if (!new_transport) {
-                       new_transport = asoc->peer.active_path;
+                       /*
+                        * If we have a prior transport pointer, see if
+                        * the destination address of the chunk
+                        * matches the destination address of the
+                        * current transport.  If not a match, then
+                        * try to look up the transport with a given
+                        * destination address.  We do this because
+                        * after processing ASCONFs, we may have new
+                        * transports created.
+                        */
+                       if (transport &&
+                           sctp_cmp_addr_exact(&chunk->dest,
+                                               &transport->ipaddr))
+                                       new_transport = transport;
+                       else
+                               new_transport = sctp_assoc_lookup_paddr(asoc,
+                                                               &chunk->dest);
+
+                       /* if we still don't have a new transport, then
+                        * use the current active path.
+                        */
+                       if (!new_transport)
+                               new_transport = asoc->peer.active_path;
                } else if ((new_transport->state == SCTP_INACTIVE) ||
                           (new_transport->state == SCTP_UNCONFIRMED)) {
                        /* If the chunk is Heartbeat or Heartbeat Ack,
@@ -729,9 +782,12 @@ int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
                         * address of the IP datagram containing the
                         * HEARTBEAT chunk to which this ack is responding.
                         * ...
+                        *
+                        * ASCONF_ACKs also must be sent to the source.
                         */
                        if (chunk->chunk_hdr->type != SCTP_CID_HEARTBEAT &&
-                           chunk->chunk_hdr->type != SCTP_CID_HEARTBEAT_ACK)
+                           chunk->chunk_hdr->type != SCTP_CID_HEARTBEAT_ACK &&
+                           chunk->chunk_hdr->type != SCTP_CID_ASCONF_ACK)
                                new_transport = asoc->peer.active_path;
                }
 
@@ -768,20 +824,36 @@ int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
                        break;
 
                case SCTP_CID_ABORT:
-               case SCTP_CID_SACK:
-               case SCTP_CID_HEARTBEAT:
+                       if (sctp_test_T_bit(chunk)) {
+                               packet->vtag = asoc->c.my_vtag;
+                       }
+               /* The following chunks are "response" chunks, i.e.
+                * they are generated in response to something we
+                * received.  If we are sending these, then we can
+                * send only 1 packet containing these chunks.
+                */
                case SCTP_CID_HEARTBEAT_ACK:
-               case SCTP_CID_SHUTDOWN:
                case SCTP_CID_SHUTDOWN_ACK:
-               case SCTP_CID_ERROR:
-               case SCTP_CID_COOKIE_ECHO:
                case SCTP_CID_COOKIE_ACK:
-               case SCTP_CID_ECN_ECNE:
+               case SCTP_CID_COOKIE_ECHO:
+               case SCTP_CID_ERROR:
                case SCTP_CID_ECN_CWR:
-               case SCTP_CID_ASCONF:
                case SCTP_CID_ASCONF_ACK:
+                       one_packet = 1;
+                       /* Fall throught */
+
+               case SCTP_CID_SACK:
+               case SCTP_CID_HEARTBEAT:
+               case SCTP_CID_SHUTDOWN:
+               case SCTP_CID_ECN_ECNE:
+               case SCTP_CID_ASCONF:
                case SCTP_CID_FWD_TSN:
-                       sctp_packet_transmit_chunk(packet, chunk);
+                       status = sctp_packet_transmit_chunk(packet, chunk,
+                                                           one_packet);
+                       if (status  != SCTP_XMIT_OK) {
+                               /* put the chunk back */
+                               list_add(&chunk->list, &q->control_chunk_list);
+                       }
                        break;
 
                default:
@@ -833,7 +905,8 @@ int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
                                                    rtx_timeout, &start_timer);
 
                        if (start_timer)
-                               sctp_transport_reset_timers(transport);
+                               sctp_transport_reset_timers(transport,
+                                                           start_timer-1);
 
                        /* This can happen on COOKIE-ECHO resend.  Only
                         * one chunk can get bundled with a COOKIE-ECHO.
@@ -849,7 +922,6 @@ int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
                }
 
                /* Finally, transmit new packets.  */
-               start_timer = 0;
                while ((chunk = sctp_outq_dequeue_data(q)) != NULL) {
                        /* RFC 2960 6.5 Every DATA chunk MUST carry a valid
                         * stream identifier.
@@ -911,7 +983,7 @@ int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
                                        atomic_read(&chunk->skb->users) : -1);
 
                        /* Add the chunk to the packet.  */
-                       status = sctp_packet_transmit_chunk(packet, chunk);
+                       status = sctp_packet_transmit_chunk(packet, chunk, 0);
 
                        switch (status) {
                        case SCTP_XMIT_PMTU_FULL:
@@ -948,7 +1020,7 @@ int sctp_outq_flush(struct sctp_outq *q, int rtx_timeout)
                        list_add_tail(&chunk->transmitted_list,
                                      &transport->transmitted);
 
-                       sctp_transport_reset_timers(transport);
+                       sctp_transport_reset_timers(transport, 0);
 
                        q->empty = 0;
 
@@ -1009,7 +1081,6 @@ static void sctp_sack_update_unack_data(struct sctp_association *assoc,
 static __u32 sctp_highest_new_tsn(struct sctp_sackhdr *sack,
                                  struct sctp_association *asoc)
 {
-       struct list_head *ltransport, *lchunk;
        struct sctp_transport *transport;
        struct sctp_chunk *chunk;
        __u32 highest_new_tsn, tsn;
@@ -1017,12 +1088,9 @@ static __u32 sctp_highest_new_tsn(struct sctp_sackhdr *sack,
 
        highest_new_tsn = ntohl(sack->cum_tsn_ack);
 
-       list_for_each(ltransport, transport_list) {
-               transport = list_entry(ltransport, struct sctp_transport,
-                                      transports);
-               list_for_each(lchunk, &transport->transmitted) {
-                       chunk = list_entry(lchunk, struct sctp_chunk,
-                                          transmitted_list);
+       list_for_each_entry(transport, transport_list, transports) {
+               list_for_each_entry(chunk, &transport->transmitted,
+                               transmitted_list) {
                        tsn = ntohl(chunk->subh.data_hdr->tsn);
 
                        if (!chunk->tsn_gap_acked &&
@@ -1045,7 +1113,7 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
        struct sctp_association *asoc = q->asoc;
        struct sctp_transport *transport;
        struct sctp_chunk *tchunk = NULL;
-       struct list_head *lchunk, *transport_list, *pos, *temp;
+       struct list_head *lchunk, *transport_list, *temp;
        sctp_sack_variable_t *frags = sack->variable;
        __u32 sack_ctsn, ctsn, tsn;
        __u32 highest_tsn, highest_new_tsn;
@@ -1053,12 +1121,13 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
        unsigned outstanding;
        struct sctp_transport *primary = asoc->peer.primary_path;
        int count_of_newacks = 0;
+       int gap_ack_blocks;
 
        /* Grab the association's destination address list. */
        transport_list = &asoc->peer.transport_addr_list;
 
        sack_ctsn = ntohl(sack->cum_tsn_ack);
-
+       gap_ack_blocks = ntohs(sack->num_gap_ack_blocks);
        /*
         * SFR-CACC algorithm:
         * On receipt of a SACK the sender SHOULD execute the
@@ -1068,38 +1137,38 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
         * on the current primary, the CHANGEOVER_ACTIVE flag SHOULD be
         * cleared. The CYCLING_CHANGEOVER flag SHOULD also be cleared for
         * all destinations.
-        */
-       if (TSN_lte(primary->cacc.next_tsn_at_change, sack_ctsn)) {
-               primary->cacc.changeover_active = 0;
-               list_for_each(pos, transport_list) {
-                       transport = list_entry(pos, struct sctp_transport,
-                                       transports);
-                       transport->cacc.cycling_changeover = 0;
-               }
-       }
-
-       /*
-        * SFR-CACC algorithm:
         * 2) If the SACK contains gap acks and the flag CHANGEOVER_ACTIVE
         * is set the receiver of the SACK MUST take the following actions:
         *
         * A) Initialize the cacc_saw_newack to 0 for all destination
         * addresses.
+        *
+        * Only bother if changeover_active is set. Otherwise, this is
+        * totally suboptimal to do on every SACK.
         */
-       if (sack->num_gap_ack_blocks &&
-           primary->cacc.changeover_active) {
-               list_for_each(pos, transport_list) {
-                       transport = list_entry(pos, struct sctp_transport,
-                                       transports);
-                       transport->cacc.cacc_saw_newack = 0;
+       if (primary->cacc.changeover_active) {
+               u8 clear_cycling = 0;
+
+               if (TSN_lte(primary->cacc.next_tsn_at_change, sack_ctsn)) {
+                       primary->cacc.changeover_active = 0;
+                       clear_cycling = 1;
+               }
+
+               if (clear_cycling || gap_ack_blocks) {
+                       list_for_each_entry(transport, transport_list,
+                                       transports) {
+                               if (clear_cycling)
+                                       transport->cacc.cycling_changeover = 0;
+                               if (gap_ack_blocks)
+                                       transport->cacc.cacc_saw_newack = 0;
+                       }
                }
        }
 
        /* Get the highest TSN in the sack. */
        highest_tsn = sack_ctsn;
-       if (sack->num_gap_ack_blocks)
-               highest_tsn +=
-                   ntohs(frags[ntohs(sack->num_gap_ack_blocks) - 1].gab.end);
+       if (gap_ack_blocks)
+               highest_tsn += ntohs(frags[gap_ack_blocks - 1].gab.end);
 
        if (TSN_lt(asoc->highest_sacked, highest_tsn)) {
                highest_new_tsn = highest_tsn;
@@ -1108,20 +1177,18 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
                highest_new_tsn = sctp_highest_new_tsn(sack, asoc);
        }
 
+
        /* Run through the retransmit queue.  Credit bytes received
         * and free those chunks that we can.
         */
        sctp_check_transmitted(q, &q->retransmit, NULL, sack, highest_new_tsn);
-       sctp_mark_missing(q, &q->retransmit, NULL, highest_new_tsn, 0);
 
        /* Run through the transmitted queue.
         * Credit bytes received and free those chunks which we can.
         *
         * This is a MASSIVE candidate for optimization.
         */
-       list_for_each(pos, transport_list) {
-               transport  = list_entry(pos, struct sctp_transport,
-                                       transports);
+       list_for_each_entry(transport, transport_list, transports) {
                sctp_check_transmitted(q, &transport->transmitted,
                                       transport, sack, highest_new_tsn);
                /*
@@ -1133,11 +1200,10 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
                        count_of_newacks ++;
        }
 
-       list_for_each(pos, transport_list) {
-               transport  = list_entry(pos, struct sctp_transport,
-                                       transports);
-               sctp_mark_missing(q, &transport->transmitted, transport,
-                                 highest_new_tsn, count_of_newacks);
+       if (gap_ack_blocks) {
+               list_for_each_entry(transport, transport_list, transports)
+                       sctp_mark_missing(q, &transport->transmitted, transport,
+                                         highest_new_tsn, count_of_newacks);
        }
 
        /* Move the Cumulative TSN Ack Point if appropriate.  */
@@ -1154,8 +1220,10 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
                tchunk = list_entry(lchunk, struct sctp_chunk,
                                    transmitted_list);
                tsn = ntohl(tchunk->subh.data_hdr->tsn);
-               if (TSN_lte(tsn, ctsn))
+               if (TSN_lte(tsn, ctsn)) {
+                       list_del_init(&tchunk->transmitted_list);
                        sctp_chunk_free(tchunk);
+               }
        }
 
        /* ii) Set rwnd equal to the newly received a_rwnd minus the
@@ -1176,23 +1244,20 @@ int sctp_outq_sack(struct sctp_outq *q, struct sctp_sackhdr *sack)
        sctp_generate_fwdtsn(q, sack_ctsn);
 
        SCTP_DEBUG_PRINTK("%s: sack Cumulative TSN Ack is 0x%x.\n",
-                         __FUNCTION__, sack_ctsn);
+                         __func__, sack_ctsn);
        SCTP_DEBUG_PRINTK("%s: Cumulative TSN Ack of association, "
                          "%p is 0x%x. Adv peer ack point: 0x%x\n",
-                         __FUNCTION__, asoc, ctsn, asoc->adv_peer_ack_point);
+                         __func__, asoc, ctsn, asoc->adv_peer_ack_point);
 
        /* See if all chunks are acked.
         * Make sure the empty queue handler will get run later.
         */
        q->empty = (list_empty(&q->out_chunk_list) &&
-                   list_empty(&q->control_chunk_list) &&
                    list_empty(&q->retransmit));
        if (!q->empty)
                goto finish;
 
-       list_for_each(pos, transport_list) {
-               transport  = list_entry(pos, struct sctp_transport,
-                                       transports);
+       list_for_each_entry(transport, transport_list, transports) {
                q->empty = q->empty && list_empty(&transport->transmitted);
                if (!q->empty)
                        goto finish;
@@ -1237,6 +1302,7 @@ static void sctp_check_transmitted(struct sctp_outq *q,
        __u32 rtt;
        __u8 restart_timer = 0;
        int bytes_acked = 0;
+       int migrate_bytes = 0;
 
        /* These state variables are for coherent debug output. --xguo */
 
@@ -1270,8 +1336,9 @@ static void sctp_check_transmitted(struct sctp_outq *q,
                         * considering it as 'outstanding'.
                         */
                        if (!tchunk->tsn_gap_acked) {
-                               tchunk->transport->flight_size -=
-                                               sctp_data_size(tchunk);
+                               if (tchunk->transport)
+                                       tchunk->transport->flight_size -=
+                                                       sctp_data_size(tchunk);
                                q->outstanding_bytes -= sctp_data_size(tchunk);
                        }
                        continue;
@@ -1305,6 +1372,20 @@ static void sctp_check_transmitted(struct sctp_outq *q,
                                                                  rtt);
                                }
                        }
+
+                       /* If the chunk hasn't been marked as ACKED,
+                        * mark it and account bytes_acked if the
+                        * chunk had a valid transport (it will not
+                        * have a transport if ASCONF had deleted it
+                        * while DATA was outstanding).
+                        */
+                       if (!tchunk->tsn_gap_acked) {
+                               tchunk->tsn_gap_acked = 1;
+                               bytes_acked += sctp_data_size(tchunk);
+                               if (!tchunk->transport)
+                                       migrate_bytes += sctp_data_size(tchunk);
+                       }
+
                        if (TSN_lte(tsn, sack_ctsn)) {
                                /* RFC 2960  6.3.2 Retransmission Timer Rules
                                 *
@@ -1318,8 +1399,6 @@ static void sctp_check_transmitted(struct sctp_outq *q,
                                restart_timer = 1;
 
                                if (!tchunk->tsn_gap_acked) {
-                                       tchunk->tsn_gap_acked = 1;
-                                       bytes_acked += sctp_data_size(tchunk);
                                        /*
                                         * SFR-CACC algorithm:
                                         * 2) If the SACK contains gap acks
@@ -1359,10 +1438,6 @@ static void sctp_check_transmitted(struct sctp_outq *q,
                                 * older than that newly acknowledged DATA
                                 * chunk, are qualified as 'Stray DATA chunks'.
                                 */
-                               if (!tchunk->tsn_gap_acked) {
-                                       tchunk->tsn_gap_acked = 1;
-                                       bytes_acked += sctp_data_size(tchunk);
-                               }
                                list_add_tail(lchunk, &tlist);
                        }
 
@@ -1414,11 +1489,12 @@ static void sctp_check_transmitted(struct sctp_outq *q,
                        if (tchunk->tsn_gap_acked) {
                                SCTP_DEBUG_PRINTK("%s: Receiver reneged on "
                                                  "data TSN: 0x%x\n",
-                                                 __FUNCTION__,
+                                                 __func__,
                                                  tsn);
                                tchunk->tsn_gap_acked = 0;
 
-                               bytes_acked -= sctp_data_size(tchunk);
+                               if (tchunk->transport)
+                                       bytes_acked -= sctp_data_size(tchunk);
 
                                /* RFC 2960 6.3.2 Retransmission Timer Rules
                                 *
@@ -1488,6 +1564,14 @@ static void sctp_check_transmitted(struct sctp_outq *q,
 #endif /* SCTP_DEBUG */
        if (transport) {
                if (bytes_acked) {
+                       /* We may have counted DATA that was migrated
+                        * to this transport due to DEL-IP operation.
+                        * Subtract those bytes, since the were never
+                        * send on this transport and shouldn't be
+                        * credited to this transport.
+                        */
+                       bytes_acked -= migrate_bytes;
+
                        /* 8.2. When an outstanding TSN is acknowledged,
                         * the endpoint shall clear the error counter of
                         * the destination transport address to which the
@@ -1514,7 +1598,9 @@ static void sctp_check_transmitted(struct sctp_outq *q,
                                                  bytes_acked);
 
                        transport->flight_size -= bytes_acked;
-                       q->outstanding_bytes -= bytes_acked;
+                       if (transport->flight_size == 0)
+                               transport->partial_bytes_acked = 0;
+                       q->outstanding_bytes -= bytes_acked + migrate_bytes;
                } else {
                        /* RFC 2960 6.1, sctpimpguide-06 2.15.2
                         * When a sender is doing zero window probing, it
@@ -1531,7 +1617,7 @@ static void sctp_check_transmitted(struct sctp_outq *q,
                            (sack_ctsn+2 == q->asoc->next_tsn)) {
                                SCTP_DEBUG_PRINTK("%s: SACK received for zero "
                                                  "window probe: %u\n",
-                                                 __FUNCTION__, sack_ctsn);
+                                                 __func__, sack_ctsn);
                                q->asoc->overall_error_count = 0;
                                transport->error_count = 0;
                        }
@@ -1566,14 +1652,12 @@ static void sctp_mark_missing(struct sctp_outq *q,
                              int count_of_newacks)
 {
        struct sctp_chunk *chunk;
-       struct list_head *pos;
        __u32 tsn;
        char do_fast_retransmit = 0;
        struct sctp_transport *primary = q->asoc->peer.primary_path;
 
-       list_for_each(pos, transmitted_queue) {
+       list_for_each_entry(chunk, transmitted_queue, transmitted_list) {
 
-               chunk = list_entry(pos, struct sctp_chunk, transmitted_list);
                tsn = ntohl(chunk->subh.data_hdr->tsn);
 
                /* RFC 2960 7.2.4, sctpimpguide-05 2.8.2 M3) Examine all
@@ -1583,7 +1667,7 @@ static void sctp_mark_missing(struct sctp_outq *q,
                 * chunk if it has NOT been fast retransmitted or marked for
                 * fast retransmit already.
                 */
-               if (!chunk->fast_retransmit &&
+               if (chunk->fast_retransmit == SCTP_CAN_FRTX &&
                    !chunk->tsn_gap_acked &&
                    TSN_lt(tsn, highest_new_tsn_in_sack)) {
 
@@ -1596,7 +1680,7 @@ static void sctp_mark_missing(struct sctp_outq *q,
 
                                SCTP_DEBUG_PRINTK(
                                        "%s: TSN 0x%x missing counter: %d\n",
-                                       __FUNCTION__, tsn,
+                                       __func__, tsn,
                                        chunk->tsn_missing_report);
                        }
                }
@@ -1608,7 +1692,7 @@ static void sctp_mark_missing(struct sctp_outq *q,
                 */
 
                if (chunk->tsn_missing_report >= 3) {
-                       chunk->fast_retransmit = 1;
+                       chunk->fast_retransmit = SCTP_NEED_FRTX;
                        do_fast_retransmit = 1;
                }
        }
@@ -1619,7 +1703,7 @@ static void sctp_mark_missing(struct sctp_outq *q,
 
                SCTP_DEBUG_PRINTK("%s: transport: %p, cwnd: %d, "
                                  "ssthresh: %d, flight_size: %d, pba: %d\n",
-                                 __FUNCTION__, transport, transport->cwnd,
+                                 __func__, transport, transport->cwnd,
                                  transport->ssthresh, transport->flight_size,
                                  transport->partial_bytes_acked);
        }
@@ -1685,6 +1769,9 @@ static void sctp_generate_fwdtsn(struct sctp_outq *q, __u32 ctsn)
        struct sctp_chunk *chunk;
        struct list_head *lchunk, *temp;
 
+       if (!asoc->peer.prsctp_capable)
+               return;
+
        /* PR-SCTP C1) Let SackCumAck be the Cumulative TSN ACK carried in the
         * received SACK.
         *