[RESEND PATCH v3 8/9] net/tcp: define a fallback value for rcv_wnd size

[Mikhail Kshevetskiy]

Some driver implements it's own network packet pool, so PKTBUFSRX is zero.
This results in zero-size TCP receive window, so data transfer doesn't
work. Avod it by setting a reasonable fallback value.

Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy at iopsys.eu>
---
 net/tcp.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/net/tcp.c b/net/tcp.c
index 7014d5b4f43..f0889d72d44 100644
--- a/net/tcp.c
+++ b/net/tcp.c
@@ -28,7 +28,11 @@
 #define TCP_SEND_TIMEOUT	2000UL
 #define TCP_RX_INACTIVE_TIMEOUT	30000UL
 #define TCP_START_SEQ_INC	2153	/* just large prime number */
-#define TCP_RCV_WND_SIZE	(PKTBUFSRX * TCP_MSS)
+#if PKTBUFSRX != 0
+  #define TCP_RCV_WND_SIZE	(PKTBUFSRX * TCP_MSS)
+#else
+  #define TCP_RCV_WND_SIZE	(4 * TCP_MSS)
+#endif
 
 #define TCP_PACKET_OK		0
 #define TCP_PACKET_DROP		1
-- 
2.39.2