sctp: Pass sk_buff_head explicitly to sctp_ulpq_tail_event().

Now the SKB list implementation assumption can be removed.

And now that we know that the list head is always non-NULL
we can remove the code blocks dealing with that as well.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 18 deletions

diff --git a/net/sctp/ulpqueue.c b/net/sctp/ulpqueue.c
index a698f1a509bf..7cdc3623fa35 100644
--- a/net/sctp/ulpqueue.c
+++ b/net/sctp/ulpqueue.c
@@ -130,7 +130,7 @@ int sctp_ulpq_tail_data(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk,
          */
         if (event) {
                 event_eor = (event->msg_flags & MSG_EOR) ? 1 : 0;
-                sctp_ulpq_tail_event(ulpq, event);
+                sctp_ulpq_tail_event(ulpq, &temp);
         }
 
         return event_eor;
@@ -194,18 +194,17 @@ static int sctp_ulpq_clear_pd(struct sctp_ulpq *ulpq)
         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
- * of that list.
- */
-int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event)
+int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sk_buff_head *skb_list)
 {
         struct sock *sk = ulpq->asoc->base.sk;
         struct sctp_sock *sp = sctp_sk(sk);
-        struct sk_buff_head *queue, *skb_list;
-        struct sk_buff *skb = sctp_event2skb(event);
+        struct sctp_ulpevent *event;
+        struct sk_buff_head *queue;
+        struct sk_buff *skb;
         int clear_pd = 0;
 
-        skb_list = (struct sk_buff_head *) skb->prev;
+        skb = __skb_peek(skb_list);
+        event = sctp_skb2event(skb);
 
         /* If the socket is just going to throw this away, do not
          * even try to deliver it.
@@ -258,13 +257,7 @@ int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event)
                 }
         }
 
-        /* If we are harvesting multiple skbs they will be
-         * collected on a list.
-         */
-        if (skb_list)
-                skb_queue_splice_tail_init(skb_list, queue);
-        else
-                __skb_queue_tail(queue, skb);
+        skb_queue_splice_tail_init(skb_list, queue);
 
         /* Did we just complete partial delivery and need to get
          * rolling again?  Move pending data to the receive
@@ -757,7 +750,7 @@ static void sctp_ulpq_reasm_drain(struct sctp_ulpq *ulpq)
                  * sctp_ulpevent for  very first SKB on the  temp' list.
                  */
                 if (event)
-                        sctp_ulpq_tail_event(ulpq, event);
+                        sctp_ulpq_tail_event(ulpq, &temp);
         }
 }
 
@@ -957,7 +950,7 @@ static void sctp_ulpq_reap_ordered(struct sctp_ulpq *ulpq, __u16 sid)
         if (event) {
                 /* see if we have more ordered that we can deliver */
                 sctp_ulpq_retrieve_ordered(ulpq, event);
-                sctp_ulpq_tail_event(ulpq, event);
+                sctp_ulpq_tail_event(ulpq, &temp);
         }
 }
 
@@ -1087,7 +1080,7 @@ void sctp_ulpq_partial_delivery(struct sctp_ulpq *ulpq,
 
                         skb_queue_head_init(&temp);
                         __skb_queue_tail(&temp, sctp_event2skb(event));
-                        sctp_ulpq_tail_event(ulpq, event);
+                        sctp_ulpq_tail_event(ulpq, &temp);
                         sctp_ulpq_set_pd(ulpq);
                         return;
                 }