Merge remote-tracking branches 'spi/fix/ath79', 'spi/fix/atmel', 'spi/fix/coldfire...

[~andy/linux] / net / sctp / associola.c

diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 5ae60920067470463420f0b3aa879e7c0999f200..f558433537b8f829a3f6147256abb7c5d23e4b47 100644 (file)
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -1367,44 +1367,35 @@ static inline bool sctp_peer_needs_update(struct sctp_association *asoc)
        return false;
 }
 
-/* Increase asoc's rwnd by len and send any window update SACK if needed. */
-void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned int len)
+/* Update asoc's rwnd for the approximated state in the buffer,
+ * and check whether SACK needs to be sent.
+ */
+void sctp_assoc_rwnd_update(struct sctp_association *asoc, bool update_peer)
 {
+       int rx_count;
        struct sctp_chunk *sack;
        struct timer_list *timer;
 
-       if (asoc->rwnd_over) {
-               if (asoc->rwnd_over >= len) {
-                       asoc->rwnd_over -= len;
-               } else {
-                       asoc->rwnd += (len - asoc->rwnd_over);
-                       asoc->rwnd_over = 0;
-               }
-       } else {
-               asoc->rwnd += len;
-       }
+       if (asoc->ep->rcvbuf_policy)
+               rx_count = atomic_read(&asoc->rmem_alloc);
+       else
+               rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
 
-       /* If we had window pressure, start recovering it
-        * once our rwnd had reached the accumulated pressure
-        * threshold.  The idea is to recover slowly, but up
-        * to the initial advertised window.
-        */
-       if (asoc->rwnd_press && asoc->rwnd >= asoc->rwnd_press) {
-               int change = min(asoc->pathmtu, asoc->rwnd_press);
-               asoc->rwnd += change;
-               asoc->rwnd_press -= change;
-       }
+       if ((asoc->base.sk->sk_rcvbuf - rx_count) > 0)
+               asoc->rwnd = (asoc->base.sk->sk_rcvbuf - rx_count) >> 1;
+       else
+               asoc->rwnd = 0;
 
-       pr_debug("%s: asoc:%p rwnd increased by %d to (%u, %u) - %u\n",
-                __func__, asoc, len, asoc->rwnd, asoc->rwnd_over,
-                asoc->a_rwnd);
+       pr_debug("%s: asoc:%p rwnd=%u, rx_count=%d, sk_rcvbuf=%d\n",
+                __func__, asoc, asoc->rwnd, rx_count,
+                asoc->base.sk->sk_rcvbuf);
 
        /* Send a window update SACK if the rwnd has increased by at least the
         * minimum of the association's PMTU and half of the receive buffer.
         * The algorithm used is similar to the one described in
         * Section 4.2.3.3 of RFC 1122.
         */
-       if (sctp_peer_needs_update(asoc)) {
+       if (update_peer && sctp_peer_needs_update(asoc)) {
                asoc->a_rwnd = asoc->rwnd;
 
                pr_debug("%s: sending window update SACK- asoc:%p rwnd:%u "
@@ -1426,45 +1417,6 @@ void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned int len)
        }
 }
 
-/* Decrease asoc's rwnd by len. */
-void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned int len)
-{
-       int rx_count;
-       int over = 0;
-
-       if (unlikely(!asoc->rwnd || asoc->rwnd_over))
-               pr_debug("%s: association:%p has asoc->rwnd:%u, "
-                        "asoc->rwnd_over:%u!\n", __func__, asoc,
-                        asoc->rwnd, asoc->rwnd_over);
-
-       if (asoc->ep->rcvbuf_policy)
-               rx_count = atomic_read(&asoc->rmem_alloc);
-       else
-               rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
-
-       /* If we've reached or overflowed our receive buffer, announce
-        * a 0 rwnd if rwnd would still be positive.  Store the
-        * the potential pressure overflow so that the window can be restored
-        * back to original value.
-        */
-       if (rx_count >= asoc->base.sk->sk_rcvbuf)
-               over = 1;
-
-       if (asoc->rwnd >= len) {
-               asoc->rwnd -= len;
-               if (over) {
-                       asoc->rwnd_press += asoc->rwnd;
-                       asoc->rwnd = 0;
-               }
-       } else {
-               asoc->rwnd_over = len - asoc->rwnd;
-               asoc->rwnd = 0;
-       }
-
-       pr_debug("%s: asoc:%p rwnd decreased by %d to (%u, %u, %u)\n",
-                __func__, asoc, len, asoc->rwnd, asoc->rwnd_over,
-                asoc->rwnd_press);
-}
 
 /* Build the bind address list for the association based on info from the
  * local endpoint and the remote peer.