[SCTP]: Implement SCTP_FRAGMENT_INTERLEAVE socket option

This option was introduced in draft-ietf-tsvwg-sctpsocket-13.  It
prevents head-of-line blocking in the case of one-to-many endpoint.
Applications enabling this option really must enable SCTP_SNDRCV event
so that they would know where the data belongs.  Based on an
earlier patch by Ivan Skytte Jørgensen.

Additionally, this functionality now permits multiple associations
on the same endpoint to enter Partial Delivery.  Applications should
be extra careful, when using this functionality, to track EOR indicators.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 6 insertions, 3 deletions

diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index f431acf3dcea..fe7f5ae1c513 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -304,10 +304,11 @@ struct sctp_sock {
         __u32 autoclose;
         __u8 nodelay;
         __u8 disable_fragments;
-        __u8 pd_mode;
         __u8 v4mapped;
+        __u8 frag_interleave;
         __u32 adaptation_ind;
 
+        atomic_t pd_mode;
         /* Receive to here while partial delivery is in effect. */
         struct sk_buff_head pd_lobby;
 };
diff --git a/include/net/sctp/ulpqueue.h b/include/net/sctp/ulpqueue.h
index ab26ab3adae1..39ea3f442b47 100644
--- a/include/net/sctp/ulpqueue.h
+++ b/include/net/sctp/ulpqueue.h
@@ -78,7 +78,7 @@ void sctp_ulpq_partial_delivery(struct sctp_ulpq *, struct sctp_chunk *, gfp_t);
 void sctp_ulpq_abort_pd(struct sctp_ulpq *, gfp_t);
 
 /* Clear the partial data delivery condition on this socket. */
-int sctp_clear_pd(struct sock *sk);
+int sctp_clear_pd(struct sock *sk, struct sctp_association *asoc);
 
 /* Skip over an SSN. */
 void sctp_ulpq_skip(struct sctp_ulpq *ulpq, __u16 sid, __u16 ssn);
diff --git a/include/net/sctp/user.h b/include/net/sctp/user.h
index 67a30eb2b3a4..e77316088dc7 100644
--- a/include/net/sctp/user.h
+++ b/include/net/sctp/user.h
@@ -97,6 +97,8 @@ enum sctp_optname {
 #define SCTP_DELAYED_ACK_TIME SCTP_DELAYED_ACK_TIME
         SCTP_CONTEXT,   /* Receive Context */
 #define SCTP_CONTEXT SCTP_CONTEXT
+        SCTP_FRAGMENT_INTERLEAVE,
+#define SCTP_FRAGMENT_INTERLEAVE SCTP_FRAGMENT_INTERLEAVE
 
         /* Internal Socket Options. Some of the sctp library functions are 
          * implemented using these socket options.
@@ -530,7 +532,7 @@ struct sctp_paddrparams {
         __u32                   spp_flags;
 } __attribute__((packed, aligned(4)));
 
-/* 7.1.24. Delayed Ack Timer (SCTP_DELAYED_ACK_TIME)
+/* 7.1.23. Delayed Ack Timer (SCTP_DELAYED_ACK_TIME)
  *
  *   This options will get or set the delayed ack timer.  The time is set
  *   in milliseconds.  If the assoc_id is 0, then this sets or gets the