diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index fe7f5ae1c513fdef88739f8fdd2f74342e328166..37b4a24e589b2e148dc36b278759182c7417ab04 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -307,6 +307,7 @@ struct sctp_sock {
__u8 v4mapped;
__u8 frag_interleave;
__u32 adaptation_ind;
+ __u32 pd_point;
atomic_t pd_mode;
/* Receive to here while partial delivery is in effect. */
diff --git a/include/net/sctp/user.h b/include/net/sctp/user.h
index e77316088dc7535427c2ce99573c0a5212c1de4e..9a8352710631351cae83e69092fecb12c11825bb 100644
--- a/include/net/sctp/user.h
+++ b/include/net/sctp/user.h
@@ -99,6 +99,8 @@ enum sctp_optname {
#define SCTP_CONTEXT SCTP_CONTEXT
SCTP_FRAGMENT_INTERLEAVE,
#define SCTP_FRAGMENT_INTERLEAVE SCTP_FRAGMENT_INTERLEAVE
+ SCTP_PARTIAL_DELIVERY_POINT, /* Set/Get partial delivery point */
+#define SCTP_PARTIAL_DELIVERY_POINT SCTP_PARTIAL_DELIVERY_POINT
/* Internal Socket Options. Some of the sctp library functions are
* implemented using these socket options.
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index b4be473c68b05aee9cc4148df428720fc969283f..1e787a2d0b5ffa9b242f8814bf2ef8d60a8c94a2 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -2832,6 +2832,32 @@ static int sctp_setsockopt_fragment_interleave(struct sock *sk,
return 0;
}
+/*
+ * 7.1.25. Set or Get the sctp partial delivery point
+ * (SCTP_PARTIAL_DELIVERY_POINT)
+ * This option will set or get the SCTP partial delivery point. This
+ * point is the size of a message where the partial delivery API will be
+ * invoked to help free up rwnd space for the peer. Setting this to a
+ * lower value will cause partial delivery's to happen more often. The
+ * calls argument is an integer that sets or gets the partial delivery
+ * point.
+ */
+static int sctp_setsockopt_partial_delivery_point(struct sock *sk,
+ char __user *optval,
+ int optlen)
+{
+ u32 val;
+
+ if (optlen != sizeof(u32))
+ return -EINVAL;
+ if (get_user(val, (int __user *)optval))
+ return -EFAULT;
+
+ sctp_sk(sk)->pd_point = val;
+
+ return 0; /* is this the right error code? */
+}
+
/* API 6.2 setsockopt(), getsockopt()
*
* Applications use setsockopt() and getsockopt() to set or retrieve
@@ -2911,6 +2937,9 @@ SCTP_STATIC int sctp_setsockopt(struct sock *sk, int level, int optname,
case SCTP_DELAYED_ACK_TIME:
retval = sctp_setsockopt_delayed_ack_time(sk, optval, optlen);
break;
+ case SCTP_PARTIAL_DELIVERY_POINT:
+ retval = sctp_setsockopt_partial_delivery_point(sk, optval, optlen);
+ break;
case SCTP_INITMSG:
retval = sctp_setsockopt_initmsg(sk, optval, optlen);
@@ -4602,6 +4631,30 @@ static int sctp_getsockopt_fragment_interleave(struct sock *sk, int len,
return 0;
}
+/*
+ * 7.1.25. Set or Get the sctp partial delivery point
+ * (chapter and verse is quoted at sctp_setsockopt_partial_delivery_point())
+ */
+static int sctp_getsockopt_partial_delivery_point(struct sock *sk, int len,
+ char __user *optval,
+ int __user *optlen)
+{
+ u32 val;
+
+ if (len < sizeof(u32))
+ return -EINVAL;
+
+ len = sizeof(u32);
+
+ val = sctp_sk(sk)->pd_point;
+ if (put_user(len, optlen))
+ return -EFAULT;
+ if (copy_to_user(optval, &val, len))
+ return -EFAULT;
+
+ return -ENOTSUPP;
+}
+
SCTP_STATIC int sctp_getsockopt(struct sock *sk, int level, int optname,
char __user *optval, int __user *optlen)
{
@@ -4718,6 +4771,10 @@ SCTP_STATIC int sctp_getsockopt(struct sock *sk, int level, int optname,
retval = sctp_getsockopt_fragment_interleave(sk, len, optval,
optlen);
break;
+ case SCTP_PARTIAL_DELIVERY_POINT:
+ retval = sctp_getsockopt_partial_delivery_point(sk, len, optval,
+ optlen);
+ break;
default:
retval = -ENOPROTOOPT;
break;
diff --git a/net/sctp/ulpqueue.c b/net/sctp/ulpqueue.c
index ac80c34f6c2c1572cadaea0d09298f5e421f243b..0fa4d4d4df17f566a198a0685f1bcdf8015b4a82 100644
--- a/net/sctp/ulpqueue.c
+++ b/net/sctp/ulpqueue.c
@@ -177,6 +177,15 @@ int sctp_clear_pd(struct sock *sk, struct sctp_association *asoc)
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)
{
@@ -401,6 +410,11 @@ static inline struct sctp_ulpevent *sctp_ulpq_retrieve_reassembled(struct sctp_u
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
@@ -416,6 +430,10 @@ static inline struct sctp_ulpevent *sctp_ulpq_retrieve_reassembled(struct sctp_u
* 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);
@@ -423,14 +441,32 @@ static inline struct sctp_ulpevent *sctp_ulpq_retrieve_reassembled(struct sctp_u
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;
@@ -441,7 +477,28 @@ static inline struct sctp_ulpevent *sctp_ulpq_retrieve_reassembled(struct sctp_u
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;
@@ -882,8 +939,7 @@ void sctp_ulpq_partial_delivery(struct sctp_ulpq *ulpq,
/* Send event to the ULP. */
if (event) {
sctp_ulpq_tail_event(ulpq, event);
- atomic_inc(&sp->pd_mode);
- ulpq->pd_mode = 1;
+ sctp_ulpq_set_pd(ulpq);
return;
}
}