Completes basic changes to support per-device/per-link TCP receive window size

5 files changed, 78 insertions, 29 deletions

diff --git a/nuttx/include/nuttx/net/netconfig.h b/nuttx/include/nuttx/net/netconfig.h
index 556930cc7..247160355 100644
--- a/nuttx/include/nuttx/net/netconfig.h
+++ b/nuttx/include/nuttx/net/netconfig.h
@@ -88,7 +88,7 @@
  * There are other device-specific features that at tied to the link layer:
  *
  *   - Maximum Transfer Unit (MTU)
- *   - TCP Receive Window size
+ *   - TCP Receive Window size (See TCP configuration options below)
  * 
  * A better solution would be to support device-by-device MTU and receive
  * window sizes.  This minimum support is require to support the optimal
@@ -298,15 +298,17 @@
 #define TCP_MSS(d)    (NET_DEV_MTU(d) - NET_LL_HDRLEN(d) - IPTCP_HDRLEN)
 
 #ifdef CONFIG_NET_ETHERNET
-#  define MIN_TCP_MSS (CONFIG_NET_ETH_MTU - ETH_HDRLEN - IPTCP_HDRLEN)
-#else /* if defined(CONFIG_NET_SLIP) */
-#  define MIN_TCP_MSS (CONFIG_NET_SLIP_MTU - IPTCP_HDRLEN)
+#  define ETH_TCP_MSS  (CONFIG_NET_ETH_MTU - ETH_HDRLEN - IPTCP_HDRLEN)
+#  define MIN_TCP_MSS  ETH_TCP_MSS
+#elif defined(CONFIG_NET_SLIP)
+#  define SLIP_TCP_MSS (CONFIG_NET_SLIP_MTU - IPTCP_HDRLEN)
+#  define MIN_TCP_MSS  SLIP_TCP_MSS
 #endif
 
 #ifdef CONFIG_NET_SLIP
-#  define MAX_TCP_MSS (CONFIG_NET_SLIP_MTU - IPTCP_HDRLEN)
-#else /* if defined(CONFIG_NET_ETHERNET) */
-#  define MAX_TCP_MSS (CONFIG_NET_ETH_MTU - ETH_HDRLEN - IPTCP_HDRLEN)
+#  define MAX_TCP_MSS  SLIP_TCP_MSS
+#elif defined(CONFIG_NET_ETHERNET)
+#  define MAX_TCP_MSS  ETH_TCP_MSS
 #endif
 
 /* The size of the advertised receiver's window.
@@ -318,10 +320,37 @@
  * See the note above regarding the TCP MSS and CONFIG_NET_MULTILINK.
  */
 
-#ifndef CONFIG_NET_RECEIVE_WINDOW
-#  define CONFIG_NET_RECEIVE_WINDOW MIN_TCP_MSS
+#ifdef CONFIG_NET_SLIP
+#  ifndef CONFIG_NET_SLIP_TCP_RECVWNDO
+#    define CONFIG_NET_SLIP_TCP_RECVWNDO SLIP_TCP_MSS
+#  endif
 #endif
 
+#ifdef CONFIG_NET_ETHERNET
+#  ifndef CONFIG_NET_ETH_TCP_RECVWNDO
+#    define CONFIG_NET_ETH_TCP_RECVWNDO ETH_TCP_MSS
+#  endif
+#endif
+
+#if defined(CONFIG_NET_MULTILINK)
+   /* We are supporting multiple network devices using different link layer
+    * protocols.  Get the size of the receive window from the device structure.
+    */
+
+#  define NET_DEV_RCVWNDO(d)  ((d)->d_recvwndo)
+
+#elif defined(CONFIG_NET_SLIP)
+   /* Only SLIP.. use the configured SLIP receive window size */
+
+#  define NET_DEV_RCVWNDO(d)  CONFIG_NET_SLIP_TCP_RECVWNDO
+
+#else /* if defined(CONFIG_NET_ETHERNET) */
+   /* Only Ethernet.. use the configured SLIP receive window size */
+
+#  define NET_DEV_RCVWNDO(d)  CONFIG_NET_ETH_TCP_RECVWNDO
+
+#endif /* MULTILINK or SLIP or ETHERNET */
+
 /* How long a connection should stay in the TIME_WAIT state.
  *
  * This configuration option has no real implication, and it should be
diff --git a/nuttx/include/nuttx/net/netdev.h b/nuttx/include/nuttx/net/netdev.h
index 70d965be0..42fcb2848 100644
--- a/nuttx/include/nuttx/net/netdev.h
+++ b/nuttx/include/nuttx/net/netdev.h
@@ -102,6 +102,9 @@ struct net_driver_s
   uint8_t d_lltype;         /* See enum net_datalink_e */
   uint8_t d_llhdrlen;       /* Link layer header size */
   uint16_t d_mtu;           /* Maximum packet size */
+#ifdef CONFIG_NET_TCP
+  uint16_t d_recvwndo;      /* TCP receive window size */
+#endif
 #endif
 
 #ifdef CONFIG_NET_ETHERNET
diff --git a/nuttx/net/Kconfig b/nuttx/net/Kconfig
index 53f2f93e6..baad94ae0 100644
--- a/nuttx/net/Kconfig
+++ b/nuttx/net/Kconfig
@@ -29,6 +29,15 @@ config NET_NOINTS
 		Otherwise, it assumed that uIP will be called from interrupt level handling
 		and critical sections will be managed by enabling and disabling interrupts.
 
+config NET_PROMISCUOUS
+	bool "Promiscuous mode"
+	default n
+	---help---
+		Force the Ethernet driver to operate in promiscuous mode (if supported
+		by the Ethernet driver).
+
+menu "Driver buffer configuration"
+
 config NET_MULTIBUFFER
 	bool "Use multiple device-side I/O buffers"
 	default n
@@ -40,13 +49,6 @@ config NET_MULTIBUFFER
 		Or, as another example, the driver may support queuing of concurrent
 		input/ouput and output transfers for better performance.
 
-config NET_PROMISCUOUS
-	bool "Promiscuous mode"
-	default n
-	---help---
-		Force the Ethernet driver to operate in promiscuous mode (if supported
-		by the Ethernet driver).
-
 config NET_ETH_MTU
 	int "Ethernet packet buffer size (MTU)"
 	default 1294 if NET_IPv6
@@ -66,6 +68,17 @@ config NET_ETH_MTU
 		IPv6 hosts are required to be able to handle an MSS of 1220 octets,
 		resulting in a minimum buffer size of of 1220+20+40+14 = 1294
 
+config NET_ETH_TCP_RECVWNDO
+	int "Ethernet receive window size"
+	default 1220 if NET_IPv6
+	default 536 if !NET_IPv6
+	depends on NET_ETHERNET && NET_TCP
+	---help---
+		The size of the advertised receiver's window.   Should be set low
+		(i.e., to the size of the MSS) if the application is slow to process
+		incoming data, or high (32768 bytes) if the application processes
+		data quickly.
+
 config NET_SLIP_MTU
 	int # "SLIP packet buffer size (MTU)"
 	default 296
@@ -79,11 +92,10 @@ config NET_SLIP_MTU
 		support at lest 256+20+20 = 296.  Values other than 296 are not
 		recommended.
 
-config NET_RECEIVE_WINDOW
-	int "Receive window size"
-	default 1220 if !NET_SLIP && NET_IPv6
-	default 536 if !NET_SLIP && !NET_IPv6
-	default 256 if NET_SLIP && !NET_IPv6
+config NET_SLIP_TCP_RECVWNDO
+	int "SLIP receive window size"
+	default 256
+	depends on NET_SLIP && NET_TCP
 	---help---
 		The size of the advertised receiver's window.   Should be set low
 		(i.e., to the size of the MSS) if the application is slow to process
@@ -101,6 +113,8 @@ config NET_GUARDSIZE
 		packet size will be chopped down to the size indicated in the TCP
 		header.
 
+end menu # Driver buffer configuration
+
 menu "Data link support"
 
 config NET_MULTILINK
diff --git a/nuttx/net/netdev/netdev_register.c b/nuttx/net/netdev/netdev_register.c
index 26bf8ecf7..6b90e7ba7 100644
--- a/nuttx/net/netdev/netdev_register.c
+++ b/nuttx/net/netdev/netdev_register.c
@@ -135,6 +135,9 @@ int netdev_register(FAR struct net_driver_s *dev, enum net_lltype_e lltype)
           case NET_LL_ETHERNET:  /* Ethernet */
             dev->d_llhdrlen = ETH_HDRLEN;
             dev->d_mtu      = CONFIG_NET_ETH_MTU;
+#ifdef CONFIG_NET_TCP
+            dev->d_recvwndo = CONFIG_NET_ETH_RECVWNDO;
+#endif
             devfmt          = NETDEV_ETH_FORMAT;
             break;
 #endif
@@ -143,6 +146,9 @@ int netdev_register(FAR struct net_driver_s *dev, enum net_lltype_e lltype)
           case NET_LL_SLIP:      /* Serial Line Internet Protocol (SLIP) */
             dev->d_llhdrlen = 0;
             dev->d_mtu      = CONFIG_NET_SLIP_MTU;
+#ifdef CONFIG_NET_TCP
+            dev->d_recvwndo = CONFIG_NET_SLIP_RECVWNDO;
+#endif
             devfmt          = NETDEV_SLIP_FORMAT;
             break;
 #endif
@@ -151,16 +157,13 @@ int netdev_register(FAR struct net_driver_s *dev, enum net_lltype_e lltype)
           case NET_LL_PPP:       /* Point-to-Point Protocol (PPP) */
             dev->d_llhdrlen = 0;
             dev->d_mtu      = CONFIG_NET_PPP_MTU;
+#ifdef CONFIG_NET_TCP
+            dev->d_recvwndo = CONFIG_NET_PPP_RECVWNDO;
+#endif
             devfmt          = NETDEV_PPP_FORMAT;
             break;
 #endif
 
-            /* REVISIT:  Here we must also set the size of the link header
-             * header the precedes network layer headers.
-             */
-
-            break;
-
           default:
             nlldbg("ERROR: Unrecognized link type: %d\n", lltype);
             return -EINVAL;
diff --git a/nuttx/net/tcp/tcp_send.c b/nuttx/net/tcp/tcp_send.c
index d68855511..2e8d23115 100644
--- a/nuttx/net/tcp/tcp_send.c
+++ b/nuttx/net/tcp/tcp_send.c
@@ -201,8 +201,8 @@ static void tcp_sendcommon(FAR struct net_driver_s *dev,
     }
   else
     {
-      pbuf->wnd[0] = ((CONFIG_NET_RECEIVE_WINDOW) >> 8);
-      pbuf->wnd[1] = ((CONFIG_NET_RECEIVE_WINDOW) & 0xff);
+      pbuf->wnd[0] = ((NET_DEV_RCVWNDO(dev)) >> 8);
+      pbuf->wnd[1] = ((NET_DEV_RCVWNDO(dev)) & 0xff);
     }
 
   /* Finish the IP portion of the message, calculate checksums and send