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-rw-r--r--net/sctp/output.c142
1 files changed, 85 insertions, 57 deletions
diff --git a/net/sctp/output.c b/net/sctp/output.c
index 94c110dcaf1d..e25e2e20b63d 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -61,8 +61,13 @@
#include <net/sctp/checksum.h>
/* Forward declarations for private helpers. */
-static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
+static sctp_xmit_t sctp_packet_can_append_data(struct sctp_packet *packet,
struct sctp_chunk *chunk);
+static void sctp_packet_append_data(struct sctp_packet *packet,
+ struct sctp_chunk *chunk);
+static sctp_xmit_t sctp_packet_will_fit(struct sctp_packet *packet,
+ struct sctp_chunk *chunk,
+ u16 chunk_len);
/* Config a packet.
* This appears to be a followup set of initializations.
@@ -262,13 +267,20 @@ sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *packet,
{
sctp_xmit_t retval = SCTP_XMIT_OK;
__u16 chunk_len = WORD_ROUND(ntohs(chunk->chunk_hdr->length));
- size_t psize;
- size_t pmtu;
- int too_big;
SCTP_DEBUG_PRINTK("%s: packet:%p chunk:%p\n", __func__, packet,
chunk);
+ /* Data chunks are special. Before seeing what else we can
+ * bundle into this packet, check to see if we are allowed to
+ * send this DATA.
+ */
+ if (sctp_chunk_is_data(chunk)) {
+ retval = sctp_packet_can_append_data(packet, chunk);
+ if (retval != SCTP_XMIT_OK)
+ goto finish;
+ }
+
/* Try to bundle AUTH chunk */
retval = sctp_packet_bundle_auth(packet, chunk);
if (retval != SCTP_XMIT_OK)
@@ -279,51 +291,16 @@ sctp_xmit_t sctp_packet_append_chunk(struct sctp_packet *packet,
if (retval != SCTP_XMIT_OK)
goto finish;
- psize = packet->size;
- pmtu = ((packet->transport->asoc) ?
- (packet->transport->asoc->pathmtu) :
- (packet->transport->pathmtu));
-
- too_big = (psize + chunk_len > pmtu);
-
- /* Decide if we need to fragment or resubmit later. */
- if (too_big) {
- /* It's OK to fragmet at IP level if any one of the following
- * is true:
- * 1. The packet is empty (meaning this chunk is greater
- * the MTU)
- * 2. The chunk we are adding is a control chunk
- * 3. The packet doesn't have any data in it yet and data
- * requires authentication.
- */
- if (sctp_packet_empty(packet) || !sctp_chunk_is_data(chunk) ||
- (!packet->has_data && chunk->auth)) {
- /* We no longer do re-fragmentation.
- * Just fragment at the IP layer, if we
- * actually hit this condition
- */
- packet->ipfragok = 1;
- goto append;
-
- } else {
- retval = SCTP_XMIT_PMTU_FULL;
- goto finish;
- }
- }
-
-append:
- /* We believe that this chunk is OK to add to the packet (as
- * long as we have the cwnd for it).
- */
+ /* Check to see if this chunk will fit into the packet */
+ retval = sctp_packet_will_fit(packet, chunk, chunk_len);
+ if (retval != SCTP_XMIT_OK)
+ goto finish;
- /* DATA is a special case since we must examine both rwnd and cwnd
- * before we send DATA.
- */
+ /* We believe that this chunk is OK to add to the packet */
switch (chunk->chunk_hdr->type) {
case SCTP_CID_DATA:
- retval = sctp_packet_append_data(packet, chunk);
- if (SCTP_XMIT_OK != retval)
- goto finish;
+ /* Account for the data being in the packet */
+ sctp_packet_append_data(packet, chunk);
/* Disallow SACK bundling after DATA. */
packet->has_sack = 1;
/* Disallow AUTH bundling after DATA */
@@ -633,16 +610,15 @@ nomem:
* 2nd Level Abstractions
********************************************************************/
-/* This private function handles the specifics of appending DATA chunks. */
-static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
+/* This private function check to see if a chunk can be added */
+static sctp_xmit_t sctp_packet_can_append_data(struct sctp_packet *packet,
struct sctp_chunk *chunk)
{
sctp_xmit_t retval = SCTP_XMIT_OK;
- size_t datasize, rwnd, inflight;
+ size_t datasize, rwnd, inflight, flight_size;
struct sctp_transport *transport = packet->transport;
__u32 max_burst_bytes;
struct sctp_association *asoc = transport->asoc;
- struct sctp_sock *sp = sctp_sk(asoc->base.sk);
struct sctp_outq *q = &asoc->outqueue;
/* RFC 2960 6.1 Transmission of DATA Chunks
@@ -659,7 +635,8 @@ static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
*/
rwnd = asoc->peer.rwnd;
- inflight = asoc->outqueue.outstanding_bytes;
+ inflight = q->outstanding_bytes;
+ flight_size = transport->flight_size;
datasize = sctp_data_size(chunk);
@@ -682,8 +659,8 @@ static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
* cwnd = flightsize + Max.Burst * MTU
*/
max_burst_bytes = asoc->max_burst * asoc->pathmtu;
- if ((transport->flight_size + max_burst_bytes) < transport->cwnd) {
- transport->cwnd = transport->flight_size + max_burst_bytes;
+ if ((flight_size + max_burst_bytes) < transport->cwnd) {
+ transport->cwnd = flight_size + max_burst_bytes;
SCTP_DEBUG_PRINTK("%s: cwnd limited by max_burst: "
"transport: %p, cwnd: %d, "
"ssthresh: %d, flight_size: %d, "
@@ -708,7 +685,7 @@ static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
* ignore the value of cwnd and SHOULD NOT delay retransmission.
*/
if (chunk->fast_retransmit != SCTP_NEED_FRTX)
- if (transport->flight_size >= transport->cwnd) {
+ if (flight_size >= transport->cwnd) {
retval = SCTP_XMIT_RWND_FULL;
goto finish;
}
@@ -718,8 +695,8 @@ static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
* if any previously transmitted data on the connection remains
* unacknowledged.
*/
- if (!sp->nodelay && sctp_packet_empty(packet) &&
- q->outstanding_bytes && sctp_state(asoc, ESTABLISHED)) {
+ if (!sctp_sk(asoc->base.sk)->nodelay && sctp_packet_empty(packet) &&
+ inflight && sctp_state(asoc, ESTABLISHED)) {
unsigned len = datasize + q->out_qlen;
/* Check whether this chunk and all the rest of pending
@@ -732,6 +709,19 @@ static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
}
}
+finish:
+ return retval;
+}
+
+/* This private function does management things when adding DATA chunk */
+static void sctp_packet_append_data(struct sctp_packet *packet,
+ struct sctp_chunk *chunk)
+{
+ struct sctp_transport *transport = packet->transport;
+ size_t datasize = sctp_data_size(chunk);
+ struct sctp_association *asoc = transport->asoc;
+ u32 rwnd = asoc->peer.rwnd;
+
/* Keep track of how many bytes are in flight over this transport. */
transport->flight_size += datasize;
@@ -754,7 +744,45 @@ static sctp_xmit_t sctp_packet_append_data(struct sctp_packet *packet,
/* Has been accepted for transmission. */
if (!asoc->peer.prsctp_capable)
chunk->msg->can_abandon = 0;
+}
+
+static sctp_xmit_t sctp_packet_will_fit(struct sctp_packet *packet,
+ struct sctp_chunk *chunk,
+ u16 chunk_len)
+{
+ size_t psize;
+ size_t pmtu;
+ int too_big;
+ sctp_xmit_t retval = SCTP_XMIT_OK;
+
+ psize = packet->size;
+ pmtu = ((packet->transport->asoc) ?
+ (packet->transport->asoc->pathmtu) :
+ (packet->transport->pathmtu));
+
+ too_big = (psize + chunk_len > pmtu);
+
+ /* Decide if we need to fragment or resubmit later. */
+ if (too_big) {
+ /* It's OK to fragmet at IP level if any one of the following
+ * is true:
+ * 1. The packet is empty (meaning this chunk is greater
+ * the MTU)
+ * 2. The chunk we are adding is a control chunk
+ * 3. The packet doesn't have any data in it yet and data
+ * requires authentication.
+ */
+ if (sctp_packet_empty(packet) || !sctp_chunk_is_data(chunk) ||
+ (!packet->has_data && chunk->auth)) {
+ /* We no longer do re-fragmentation.
+ * Just fragment at the IP layer, if we
+ * actually hit this condition
+ */
+ packet->ipfragok = 1;
+ } else {
+ retval = SCTP_XMIT_PMTU_FULL;
+ }
+ }
-finish:
return retval;
}