net: Refactor to separate the UDP handler from the ARP handler

Call a built-in dummy if none is registered... don't require
protocols to register a handler (eliminating dummies)
NetConsole now uses the ARP handler when waiting on arp
(instead of needing a #define hack in arp.c)
Clear handlers at the end of net loop

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Acked-by: Simon Glass <sjg@chromium.org>

drivers/net/netconsole.c

@@ -63,12 +63,12 @@ void NcStart(void)
 {
 	if (!output_packet_len || memcmp(nc_ether, NetEtherNullAddr, 6)) {
 		/* going to check for input packet */
-		NetSetHandler(nc_handler);
+		net_set_udp_handler(nc_handler);
 		NetSetTimeout(net_timeout, nc_timeout);
 	} else {
 		/* send arp request */
 		uchar *pkt;
-		NetSetHandler(nc_wait_arp_handler);
+		net_set_arp_handler(nc_wait_arp_handler);
 		pkt = (uchar *)NetTxPacket + NetEthHdrSize() + IP_UDP_HDR_SIZE;
 		memcpy(pkt, output_packet, output_packet_len);
 		NetSendUDPPacket(nc_ether, nc_ip, nc_port, nc_port,

include/net.h

@@ -460,8 +460,10 @@ extern int	NetCksumOk(uchar *, int);	/* Return true if cksum OK */
 extern uint	NetCksum(uchar *, int);		/* Calculate the checksum */
 
 /* Callbacks */
-extern rxhand_f *NetGetHandler(void);		/* Get RX packet handler */
-extern void	NetSetHandler(rxhand_f *);	/* Set RX packet handler */
+extern rxhand_f *net_get_udp_handler(void);	/* Get UDP RX packet handler */
+extern void net_set_udp_handler(rxhand_f *);	/* Set UDP RX packet handler */
+extern rxhand_f *net_get_arp_handler(void);	/* Get ARP RX packet handler */
+extern void net_set_arp_handler(rxhand_f *);	/* Set ARP RX packet handler */
 extern void net_set_icmp_handler(rxhand_icmp_f *f); /* Set ICMP RX handler */
 extern void	NetSetTimeout(ulong, thand_f *);/* Set timeout handler */
 
@@ -487,6 +489,7 @@ static inline void NetSendPacket(uchar *pkt, int len)
 
 /*
  * Transmit UDP packet, performing ARP request if needed
+ *  (ether will be populated)
  *
  * @param ether Raw packet buffer
  * @param dest IP address to send the datagram to

net/arp.c

@@ -192,9 +192,9 @@ void ArpReceive(struct ethernet_hdr *et, struct ip_udp_hdr *ip, int len)
 			memcpy(NetArpWaitPacketMAC,
 				&arp->ar_sha, ARP_HLEN);
 
-#ifdef CONFIG_NETCONSOLE
-			NetGetHandler()(0, 0, 0, 0, 0);
-#endif
+			net_get_arp_handler()((uchar *)arp, 0, reply_ip_addr,
+				0, len);
+
 			/* modify header, and transmit it */
 			memcpy(((struct ethernet_hdr *)NetArpWaitTxPacket)->
 				et_dest, NetArpWaitPacketMAC, ARP_HLEN);

net/bootp.c

@@ -669,9 +669,9 @@ BootpRequest(void)
 
 #if defined(CONFIG_CMD_DHCP)
 	dhcp_state = SELECTING;
-	NetSetHandler(DhcpHandler);
+	net_set_udp_handler(DhcpHandler);
 #else
-	NetSetHandler(BootpHandler);
+	net_set_udp_handler(BootpHandler);
 #endif
 	NetSendPacket(NetTxPacket, pktlen);
 }

net/cdp.c

@@ -238,13 +238,6 @@ CDPTimeout(void)
 		net_set_state(NETLOOP_SUCCESS);
 }
 
-static void
-CDPDummyHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
-		unsigned len)
-{
-	/* nothing */
-}
-
 void cdp_receive(const uchar *pkt, unsigned len)
 {
 	const uchar *t;
@@ -368,7 +361,6 @@ CDPStart(void)
 	CDPApplianceVLAN = htons(-1);
 
 	NetSetTimeout(CDP_TIMEOUT, CDPTimeout);
-	NetSetHandler(CDPDummyHandler);
 
 	CDPSendTrigger();
 }

net/dns.c

@@ -200,7 +200,7 @@ DnsStart(void)
 	debug("%s\n", __func__);
 
 	NetSetTimeout(DNS_TIMEOUT, DnsTimeout);
-	NetSetHandler(DnsHandler);
+	net_set_udp_handler(DnsHandler);
 
 	DnsSend();
 }

net/net.c

@@ -178,10 +178,13 @@ uchar PktBuf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
 /* Receive packet */
 uchar *NetRxPackets[PKTBUFSRX];
 
-/* Current RX packet handler */
-static rxhand_f *packetHandler;
+/* Current UDP RX packet handler */
+static rxhand_f *udp_packet_handler;
+/* Current ARP RX packet handler */
+static rxhand_f *arp_packet_handler;
 #ifdef CONFIG_CMD_TFTPPUT
-static rxhand_icmp_f *packet_icmp_handler;	/* Current ICMP rx handler */
+/* Current ICMP rx handler */
+static rxhand_icmp_f *packet_icmp_handler;
 #endif
 /* Current timeout handler */
 static thand_f *timeHandler;
@@ -250,6 +253,18 @@ static void NetInitLoop(enum proto_t protocol)
 	return;
 }
 
+static void net_clear_handlers(void)
+{
+	net_set_udp_handler(NULL);
+	net_set_arp_handler(NULL);
+	NetSetTimeout(0, NULL);
+}
+
+static void net_cleanup_loop(void)
+{
+	net_clear_handlers();
+}
+
 /**********************************************************************/
 /*
  *	Main network processing loop.
@@ -257,6 +272,7 @@ static void NetInitLoop(enum proto_t protocol)
 
 int NetLoop(enum proto_t protocol)
 {
+	int	i;
 	bd_t *bd = gd->bd;
 	int ret = -1;
 
@@ -267,17 +283,15 @@ int NetLoop(enum proto_t protocol)
 	NetTryCount = 1;
 
 	ArpInit();
+	net_clear_handlers();
 
-	if (!NetTxPacket) {
-		int	i;
-		/*
-		 *	Setup packet buffers, aligned correctly.
-		 */
-		NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
-		NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
-		for (i = 0; i < PKTBUFSRX; i++)
-			NetRxPackets[i] = NetTxPacket + (i+1)*PKTSIZE_ALIGN;
-	}
+	/*
+	 *	Setup packet buffers, aligned correctly.
+	 */
+	NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
+	NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
+	for (i = 0; i < PKTBUFSRX; i++)
+		NetRxPackets[i] = NetTxPacket + (i+1)*PKTSIZE_ALIGN;
 
 	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
 	eth_halt();
@@ -416,6 +430,7 @@ restart:
 		 *	Abort if ctrl-c was pressed.
 		 */
 		if (ctrlc()) {
+			net_cleanup_loop();
 			eth_halt();
 			puts("\nAbort\n");
 			goto done;
@@ -458,6 +473,7 @@ restart:
 			goto restart;
 
 		case NETLOOP_SUCCESS:
+			net_cleanup_loop();
 			if (NetBootFileXferSize > 0) {
 				char buf[20];
 				printf("Bytes transferred = %ld (%lx hex)\n",
@@ -474,6 +490,7 @@ restart:
 			goto done;
 
 		case NETLOOP_FAIL:
+			net_cleanup_loop();
 			goto done;
 
 		case NETLOOP_CONTINUE:
@@ -484,7 +501,7 @@ restart:
 done:
 #ifdef CONFIG_CMD_TFTPPUT
 	/* Clear out the handlers */
-	NetSetHandler(NULL);
+	net_set_udp_handler(NULL);
 	net_set_icmp_handler(NULL);
 #endif
 	return ret;
@@ -498,13 +515,6 @@ startAgainTimeout(void)
 	net_set_state(NETLOOP_RESTART);
 }
 
-static void
-startAgainHandler(uchar *pkt, unsigned dest, IPaddr_t sip,
-		  unsigned src, unsigned len)
-{
-	/* Totally ignore the packet */
-}
-
 void NetStartAgain(void)
 {
 	char *nretry;
@@ -541,7 +551,7 @@ void NetStartAgain(void)
 		NetRestartWrap = 0;
 		if (NetDevExists) {
 			NetSetTimeout(10000UL, startAgainTimeout);
-			NetSetHandler(startAgainHandler);
+			net_set_udp_handler(NULL);
 		} else {
 			net_set_state(NETLOOP_FAIL);
 		}
@@ -555,17 +565,36 @@ void NetStartAgain(void)
  *	Miscelaneous bits.
  */
 
-rxhand_f *
-NetGetHandler(void)
+static void dummy_handler(uchar *pkt, unsigned dport,
+			IPaddr_t sip, unsigned sport,
+			unsigned len)
 {
-	return packetHandler;
 }
 
+rxhand_f *net_get_udp_handler(void)
+{
+	return udp_packet_handler;
+}
 
-void
-NetSetHandler(rxhand_f *f)
+void net_set_udp_handler(rxhand_f *f)
+{
+	if (f == NULL)
+		udp_packet_handler = dummy_handler;
+	else
+		udp_packet_handler = f;
+}
+
+rxhand_f *net_get_arp_handler(void)
 {
-	packetHandler = f;
+	return arp_packet_handler;
+}
+
+void net_set_arp_handler(rxhand_f *f)
+{
+	if (f == NULL)
+		arp_packet_handler = dummy_handler;
+	else
+		arp_packet_handler = f;
 }
 
 #ifdef CONFIG_CMD_TFTPPUT
@@ -1091,11 +1120,11 @@ NetReceive(uchar *inpkt, int len)
 		/*
 		 *	IP header OK.  Pass the packet to the current handler.
 		 */
-		(*packetHandler)((uchar *)ip + IP_UDP_HDR_SIZE,
-					ntohs(ip->udp_dst),
-					src_ip,
-					ntohs(ip->udp_src),
-					ntohs(ip->udp_len) - UDP_HDR_SIZE);
+		(*udp_packet_handler)((uchar *)ip + IP_UDP_HDR_SIZE,
+				ntohs(ip->udp_dst),
+				src_ip,
+				ntohs(ip->udp_src),
+				ntohs(ip->udp_len) - UDP_HDR_SIZE);
 		break;
 	}
 }

net/nfs.c

@@ -735,7 +735,7 @@ NfsStart(void)
 		"Loading: *\b", load_addr);
 
 	NetSetTimeout(NFS_TIMEOUT, NfsTimeout);
-	NetSetHandler(NfsHandler);
+	net_set_udp_handler(NfsHandler);
 
 	NfsTimeoutCount = 0;
 	NfsState = STATE_PRCLOOKUP_PROG_MOUNT_REQ;

net/sntp.c

@@ -85,7 +85,7 @@ SntpStart(void)
 	debug("%s\n", __func__);
 
 	NetSetTimeout(SNTP_TIMEOUT, SntpTimeout);
-	NetSetHandler(SntpHandler);
+	net_set_udp_handler(SntpHandler);
 	memset(NetServerEther, 0, sizeof(NetServerEther));
 
 	SntpSend();

net/tftp.c

@@ -778,7 +778,7 @@ void TftpStart(enum proto_t protocol)
 	TftpTimeoutCountMax = TftpRRQTimeoutCountMax;
 
 	NetSetTimeout(TftpTimeoutMSecs, TftpTimeout);
-	NetSetHandler(TftpHandler);
+	net_set_udp_handler(TftpHandler);
 #ifdef CONFIG_CMD_TFTPPUT
 	net_set_icmp_handler(icmp_handler);
 #endif
@@ -840,7 +840,7 @@ TftpStartServer(void)
 #endif
 
 	TftpState = STATE_RECV_WRQ;
-	NetSetHandler(TftpHandler);
+	net_set_udp_handler(TftpHandler);
 }
 #endif /* CONFIG_CMD_TFTPSRV */