/* Flush the reassembly and ordering queues. */
-static void sctp_ulpq_flush(struct sctp_ulpq *ulpq)
+void sctp_ulpq_flush(struct sctp_ulpq *ulpq)
{
struct sk_buff *skb;
struct sctp_ulpevent *event;
/* 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 (event->msg_flags & MSG_NOTIFICATION)
- 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.
*/
if (last)
last->next = pos;
- else {
- if (skb_cloned(f_frag)) {
- /* This is a cloned skb, we can't just modify
- * the frag_list. We need a new skb to do that.
- * Instead of calling skb_unshare(), we'll do it
- * ourselves since we need to delay the free.
- */
- new = skb_copy(f_frag, GFP_ATOMIC);
- if (!new)
- return NULL; /* try again later */
-
- sctp_skb_set_owner_r(new, f_frag->sk);
-
- skb_shinfo(new)->frag_list = pos;
- } else
- skb_shinfo(f_frag)->frag_list = pos;
- }
+ else {
+ if (skb_cloned(f_frag)) {
+ /* This is a cloned skb, we can't just modify
+ * the frag_list. We need a new skb to do that.
+ * Instead of calling skb_unshare(), we'll do it
+ * ourselves since we need to delay the free.
+ */
+ new = skb_copy(f_frag, GFP_ATOMIC);
+ if (!new)
+ return NULL; /* try again later */
+
+ sctp_skb_set_owner_r(new, f_frag->sk);
+
+ skb_shinfo(new)->frag_list = pos;
+ } else
+ skb_shinfo(f_frag)->frag_list = pos;
+ }
/* Remove the first fragment from the reassembly queue. */
__skb_unlink(f_frag, queue);
- /* if we did unshare, then free the old skb and re-assign */
- if (new) {
- kfree_skb(f_frag);
- f_frag = new;
- }
+ /* if we did unshare, then free the old skb and re-assign */
+ if (new) {
+ kfree_skb(f_frag);
+ f_frag = new;
+ }
while (pos) {
/* Remove the fragment from the reassembly queue. */
__skb_unlink(pos, queue);
-
+
/* Break if we have reached the last fragment. */
if (pos == l_frag)
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
sid = event->stream;
ssn = event->ssn;
-
+
cevent = (struct sctp_ulpevent *) pos->cb;
csid = cevent->stream;
cssn = cevent->ssn;
if (cssn != sctp_ssn_peek(in, csid))
break;
- /* Found it, so mark in the ssnmap. */
+ /* Found it, so mark in the ssnmap. */
sctp_ssn_next(in, csid);
__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));
sctp_ssn_skip(in, sid, ssn);
/* Go find any other chunks that were waiting for
- * ordering and deliver them if needed.
+ * ordering and deliver them if needed.
*/
sctp_ulpq_reap_ordered(ulpq);
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;
}
}
if (chunk) {
needed = ntohs(chunk->chunk_hdr->length);
needed -= sizeof(sctp_data_chunk_t);
- } else
+ } else
needed = SCTP_DEFAULT_MAXWINDOW;
freed = 0;
tsn = ntohl(chunk->subh.data_hdr->tsn);
sctp_tsnmap_mark(&asoc->peer.tsn_map, tsn);
sctp_ulpq_tail_data(ulpq, chunk, gfp);
-
+
sctp_ulpq_partial_delivery(ulpq, chunk, gfp);
}