* Figure out how much space we have available
*/
available_space = transport_max_rx_enqueue (&tc->connection);
+
+ /* Make sure we have a multiple of 1 << rcv_wscale. We round down to
+ * avoid advertising a window larger than what can be buffered */
+ available_space = round_down_pow2 (available_space, 1 << tc->rcv_wscale);
+
if (PREDICT_FALSE (available_space < tc->rcv_opts.mss))
{
tc->rcv_wnd = 0;
/* Bad. Thou shalt not shrink */
if (PREDICT_FALSE ((i32) available_space < observed_wnd))
{
- wnd = clib_max (observed_wnd, 0);
+ wnd = round_pow2 (clib_max (observed_wnd, 0), 1 << tc->rcv_wscale);
TCP_EVT (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
}
else
wnd = available_space;
}
- /* Make sure we have a multiple of 1 << rcv_wscale. We round up to
- * avoid advertising a window less than mss which could happen if
- * 1 << rcv_wscale < mss */
- if (wnd && tc->rcv_wscale)
- wnd = round_pow2 (wnd, 1 << tc->rcv_wscale);
-
tc->rcv_wnd = clib_min (wnd, TCP_WND_MAX << tc->rcv_wscale);
}
return 0 == (x & (x - 1));
}
+always_inline uword
+round_down_pow2 (uword x, uword pow2)
+{
+ return (x) & ~(pow2 - 1);
+}
+
always_inline uword
round_pow2 (uword x, uword pow2)
{