/* Clear the partial delivery mode for this socket. Note: This
* assumes that no association is currently in partial delivery mode.
*/
-int sctp_clear_pd(struct sock *sk)
+int sctp_clear_pd(struct sock *sk, struct sctp_association *asoc)
{
struct sctp_sock *sp = sctp_sk(sk);
- sp->pd_mode = 0;
- if (!skb_queue_empty(&sp->pd_lobby)) {
- struct list_head *list;
- sctp_skb_list_tail(&sp->pd_lobby, &sk->sk_receive_queue);
- list = (struct list_head *)&sctp_sk(sk)->pd_lobby;
- INIT_LIST_HEAD(list);
- return 1;
+ if (atomic_dec_and_test(&sp->pd_mode)) {
+ /* This means there are no other associations in PD, so
+ * we can go ahead and clear out the lobby in one shot
+ */
+ if (!skb_queue_empty(&sp->pd_lobby)) {
+ struct list_head *list;
+ sctp_skb_list_tail(&sp->pd_lobby, &sk->sk_receive_queue);
+ list = (struct list_head *)&sctp_sk(sk)->pd_lobby;
+ INIT_LIST_HEAD(list);
+ return 1;
+ }
+ } else {
+ /* There are other associations in PD, so we only need to
+ * pull stuff out of the lobby that belongs to the
+ * associations that is exiting PD (all of its notifications
+ * are posted here).
+ */
+ if (!skb_queue_empty(&sp->pd_lobby) && asoc) {
+ struct sk_buff *skb, *tmp;
+ struct sctp_ulpevent *event;
+
+ sctp_skb_for_each(skb, &sp->pd_lobby, tmp) {
+ event = sctp_skb2event(skb);
+ if (event->asoc == asoc) {
+ __skb_unlink(skb, &sp->pd_lobby);
+ __skb_queue_tail(&sk->sk_receive_queue,
+ skb);
+ }
+ }
+ }
}
+
return 0;
}
+/* Set the pd_mode on the socket and ulpq */
+static void sctp_ulpq_set_pd(struct sctp_ulpq *ulpq)
+{
+ struct sctp_sock *sp = sctp_sk(ulpq->asoc->base.sk);
+
+ atomic_inc(&sp->pd_mode);
+ ulpq->pd_mode = 1;
+}
+
/* Clear the pd_mode and restart any pending messages waiting for delivery. */
static int sctp_ulpq_clear_pd(struct sctp_ulpq *ulpq)
{
ulpq->pd_mode = 0;
- return sctp_clear_pd(ulpq->asoc->base.sk);
+ return sctp_clear_pd(ulpq->asoc->base.sk, ulpq->asoc);
}
/* If the SKB of 'event' is on a list, it is the first such member
* the association the cause of the partial delivery.
*/
- if (!sctp_sk(sk)->pd_mode) {
+ if (atomic_read(&sctp_sk(sk)->pd_mode) == 0) {
queue = &sk->sk_receive_queue;
- } else if (ulpq->pd_mode) {
- /* If the association is in partial delivery, we
- * need to finish delivering the partially processed
- * packet before passing any other data. This is
- * because we don't truly support stream interleaving.
- */
- if ((event->msg_flags & MSG_NOTIFICATION) ||
- (SCTP_DATA_NOT_FRAG ==
- (event->msg_flags & SCTP_DATA_FRAG_MASK)))
- queue = &sctp_sk(sk)->pd_lobby;
- else {
- clear_pd = event->msg_flags & MSG_EOR;
- queue = &sk->sk_receive_queue;
+ } else {
+ if (ulpq->pd_mode) {
+ /* If the association is in partial delivery, we
+ * need to finish delivering the partially processed
+ * packet before passing any other data. This is
+ * because we don't truly support stream interleaving.
+ */
+ if ((event->msg_flags & MSG_NOTIFICATION) ||
+ (SCTP_DATA_NOT_FRAG ==
+ (event->msg_flags & SCTP_DATA_FRAG_MASK)))
+ queue = &sctp_sk(sk)->pd_lobby;
+ else {
+ clear_pd = event->msg_flags & MSG_EOR;
+ queue = &sk->sk_receive_queue;
+ }
+ } else {
+ /*
+ * If fragment interleave is enabled, we
+ * can queue this to the recieve queue instead
+ * of the lobby.
+ */
+ if (sctp_sk(sk)->frag_interleave)
+ queue = &sk->sk_receive_queue;
+ else
+ queue = &sctp_sk(sk)->pd_lobby;
}
- } else
- queue = &sctp_sk(sk)->pd_lobby;
-
+ }
/* If we are harvesting multiple skbs they will be
* collected on a list.
break;
pos->next = pnext;
pos = pnext;
- };
+ }
event = sctp_skb2event(f_frag);
SCTP_INC_STATS(SCTP_MIB_REASMUSRMSGS);
struct sk_buff *first_frag = NULL;
__u32 ctsn, next_tsn;
struct sctp_ulpevent *retval = NULL;
+ struct sk_buff *pd_first = NULL;
+ struct sk_buff *pd_last = NULL;
+ size_t pd_len = 0;
+ struct sctp_association *asoc;
+ u32 pd_point;
/* Initialized to 0 just to avoid compiler warning message. Will
* never be used with this value. It is referenced only after it
* we expect to find the remaining middle fragments and the last
* fragment in order. If not, first_frag is reset to NULL and we
* start the next pass when we find another first fragment.
+ *
+ * There is a potential to do partial delivery if user sets
+ * SCTP_PARTIAL_DELIVERY_POINT option. Lets count some things here
+ * to see if can do PD.
*/
skb_queue_walk(&ulpq->reasm, pos) {
cevent = sctp_skb2event(pos);
switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) {
case SCTP_DATA_FIRST_FRAG:
+ /* If this "FIRST_FRAG" is the first
+ * element in the queue, then count it towards
+ * possible PD.
+ */
+ if (pos == ulpq->reasm.next) {
+ pd_first = pos;
+ pd_last = pos;
+ pd_len = pos->len;
+ } else {
+ pd_first = NULL;
+ pd_last = NULL;
+ pd_len = 0;
+ }
+
first_frag = pos;
next_tsn = ctsn + 1;
break;
case SCTP_DATA_MIDDLE_FRAG:
- if ((first_frag) && (ctsn == next_tsn))
+ if ((first_frag) && (ctsn == next_tsn)) {
next_tsn++;
- else
+ if (pd_first) {
+ pd_last = pos;
+ pd_len += pos->len;
+ }
+ } else
first_frag = NULL;
break;
else
first_frag = NULL;
break;
- };
+ }
+ }
+ asoc = ulpq->asoc;
+ if (pd_first) {
+ /* Make sure we can enter partial deliver.
+ * We can trigger partial delivery only if framgent
+ * interleave is set, or the socket is not already
+ * in partial delivery.
+ */
+ if (!sctp_sk(asoc->base.sk)->frag_interleave &&
+ atomic_read(&sctp_sk(asoc->base.sk)->pd_mode))
+ goto done;
+
+ cevent = sctp_skb2event(pd_first);
+ pd_point = sctp_sk(asoc->base.sk)->pd_point;
+ if (pd_point && pd_point <= pd_len) {
+ retval = sctp_make_reassembled_event(&ulpq->reasm,
+ pd_first,
+ pd_last);
+ if (retval)
+ sctp_ulpq_set_pd(ulpq);
+ }
}
done:
return retval;
goto done;
default:
return NULL;
- };
+ }
}
/* We have the reassembled event. There is no need to look
break;
default:
return NULL;
- };
+ }
}
/* We have the reassembled event. There is no need to look
return retval;
}
+/*
+ * Flush out stale fragments from the reassembly queue when processing
+ * a Forward TSN.
+ *
+ * RFC 3758, Section 3.6
+ *
+ * After receiving and processing a FORWARD TSN, the data receiver MUST
+ * take cautions in updating its re-assembly queue. The receiver MUST
+ * remove any partially reassembled message, which is still missing one
+ * or more TSNs earlier than or equal to the new cumulative TSN point.
+ * In the event that the receiver has invoked the partial delivery API,
+ * a notification SHOULD also be generated to inform the upper layer API
+ * that the message being partially delivered will NOT be completed.
+ */
+void sctp_ulpq_reasm_flushtsn(struct sctp_ulpq *ulpq, __u32 fwd_tsn)
+{
+ struct sk_buff *pos, *tmp;
+ struct sctp_ulpevent *event;
+ __u32 tsn;
+
+ if (skb_queue_empty(&ulpq->reasm))
+ return;
+
+ skb_queue_walk_safe(&ulpq->reasm, pos, tmp) {
+ event = sctp_skb2event(pos);
+ tsn = event->tsn;
+
+ /* Since the entire message must be abandoned by the
+ * sender (item A3 in Section 3.5, RFC 3758), we can
+ * free all fragments on the list that are less then
+ * or equal to ctsn_point
+ */
+ if (TSN_lte(tsn, fwd_tsn)) {
+ __skb_unlink(pos, &ulpq->reasm);
+ sctp_ulpevent_free(event);
+ } else
+ break;
+ }
+}
+
/* Helper function to gather skbs that have possibly become
* ordered by an an incoming chunk.
*/
/* Helper function to gather skbs that have possibly become
* ordered by forward tsn skipping their dependencies.
*/
-static inline void sctp_ulpq_reap_ordered(struct sctp_ulpq *ulpq)
+static inline void sctp_ulpq_reap_ordered(struct sctp_ulpq *ulpq, __u16 sid)
{
struct sk_buff *pos, *tmp;
struct sctp_ulpevent *cevent;
csid = cevent->stream;
cssn = cevent->ssn;
- if (cssn != sctp_ssn_peek(in, csid))
+ /* Have we gone too far? */
+ if (csid > sid)
break;
- /* Found it, so mark in the ssnmap. */
- sctp_ssn_next(in, csid);
+ /* Have we not gone far enough? */
+ if (csid < sid)
+ continue;
+
+ /* see if this ssn has been marked by skipping */
+ if (!SSN_lt(cssn, sctp_ssn_peek(in, csid)))
+ break;
__skb_unlink(pos, &ulpq->lobby);
- if (!event) {
+ if (!event)
/* Create a temporary list to collect chunks on. */
event = sctp_skb2event(pos);
- __skb_queue_tail(&temp, sctp_event2skb(event));
- } else {
- /* Attach all gathered skbs to the event. */
- __skb_queue_tail(&temp, pos);
- }
+
+ /* Attach all gathered skbs to the event. */
+ __skb_queue_tail(&temp, pos);
}
/* Send event to the ULP. 'event' is the sctp_ulpevent for
* very first SKB on the 'temp' list.
*/
- if (event)
+ if (event) {
+ /* see if we have more ordered that we can deliver */
+ sctp_ulpq_retrieve_ordered(ulpq, event);
sctp_ulpq_tail_event(ulpq, event);
+ }
}
-/* Skip over an SSN. */
+/* Skip over an SSN. This is used during the processing of
+ * Forwared TSN chunk to skip over the abandoned ordered data
+ */
void sctp_ulpq_skip(struct sctp_ulpq *ulpq, __u16 sid, __u16 ssn)
{
struct sctp_stream *in;
/* Go find any other chunks that were waiting for
* ordering and deliver them if needed.
*/
- sctp_ulpq_reap_ordered(ulpq);
+ sctp_ulpq_reap_ordered(ulpq, sid);
return;
}
{
struct sctp_ulpevent *event;
struct sctp_association *asoc;
+ struct sctp_sock *sp;
asoc = ulpq->asoc;
+ sp = sctp_sk(asoc->base.sk);
- /* Are we already in partial delivery mode? */
- if (!sctp_sk(asoc->base.sk)->pd_mode) {
+ /* If the association is already in Partial Delivery mode
+ * we have noting to do.
+ */
+ if (ulpq->pd_mode)
+ return;
+ /* If the user enabled fragment interleave socket option,
+ * multiple associations can enter partial delivery.
+ * Otherwise, we can only enter partial delivery if the
+ * socket is not in partial deliver mode.
+ */
+ if (sp->frag_interleave || atomic_read(&sp->pd_mode) == 0) {
/* Is partial delivery possible? */
event = sctp_ulpq_retrieve_first(ulpq);
/* Send event to the ULP. */
if (event) {
sctp_ulpq_tail_event(ulpq, event);
- sctp_sk(asoc->base.sk)->pd_mode = 1;
- ulpq->pd_mode = 1;
+ sctp_ulpq_set_pd(ulpq);
return;
}
}
sctp_ulpq_partial_delivery(ulpq, chunk, gfp);
}
+ sk_stream_mem_reclaim(asoc->base.sk);
return;
}
git.openpandora.org / pandora-kernel.git / blobdiff