[PATCH 2.5.46] multiple arp_ip_targets in bonding module

[Bert Barbe]

Hi,

I posted this patch some time ago for discussion but didnt see any response,
so now I'd like to submit it for inclusion in the 2.5 kernel. As mentioned in the
subject this patch has been based on 2.5.46

This is a simple patch for the bonding module that allows multiple arp_ip_targets .
Having just one arp_ip_target would leave room for confusion when the reference
node goes down leaving other nodes to think their interface is malfunctioning.

You can also find this patch and the same for different kernel versions
at http://www.enterprise.be

TIA - regards,
Bert

-----------------------begin-cut-here----------------------
--- drivers/net/bonding.c-orig	Mon Nov  4 23:31:04 2002
+++ drivers/net/bonding.c	Mon Nov  4 23:31:25 2002
@@ -191,6 +191,9 @@
  *     - Fixed up bond_check_dev_link() (and callers): removed some magic
  *	 numbers, banished local MII_ defines, wrapped ioctl calls to
  *	 prevent EFAULT errors
+ *
+ * 2002/10/22 - Bert Barbe <bert.barbe at oracle dot com>
+ *     - Add support for multiple arp_ip_target
  */
 
 #include <linux/config.h>
@@ -237,9 +240,10 @@
 #define BOND_LINK_ARP_INTERV	0
 #endif
 
+#define MAX_ARP_IP_TARGETS 16
 static int arp_interval = BOND_LINK_ARP_INTERV;
-static char *arp_ip_target = NULL;
-static unsigned long arp_target = 0;
+static char *arp_ip_target[MAX_ARP_IP_TARGETS] = { NULL, };
+static unsigned long arp_target[MAX_ARP_IP_TARGETS] = { 0, } ;
 static u32 my_ip = 0;
 char *arp_target_hw_addr = NULL;
 
@@ -261,8 +265,8 @@
 MODULE_PARM(mode, "i");
 MODULE_PARM(arp_interval, "i");
 MODULE_PARM_DESC(arp_interval, "arp interval in milliseconds");
-MODULE_PARM(arp_ip_target, "s");
-MODULE_PARM_DESC(arp_ip_target, "arp target in n.n.n.n form");
+MODULE_PARM(arp_ip_target, "1-" __MODULE_STRING(MAX_ARP_IP_TARGETS) "s");
+MODULE_PARM_DESC(arp_ip_target, "arp target(s) in n.n.n.n form");
 MODULE_PARM_DESC(mode, "Mode of operation : 0 for round robin, 1 for active-backup, 2 for xor");
 MODULE_PARM(updelay, "i");
 MODULE_PARM_DESC(updelay, "Delay before considering link up, in milliseconds");
@@ -1488,11 +1492,17 @@
 			} else {
 				if ((jiffies - slave->dev->last_rx) <= 
 						the_delta_in_ticks)  {
-					arp_send(ARPOP_REQUEST, ETH_P_ARP, 
-						arp_target, slave->dev, 
-						my_ip, arp_target_hw_addr, 
-						slave->dev->dev_addr, 
-		  				arp_target_hw_addr); 
+                                        int i;
+                                        for ( i=0;
+                                             (i<MAX_ARP_IP_TARGETS) && arp_target[i];
+                                             i++) {
+                                            arp_send(ARPOP_REQUEST, ETH_P_ARP,
+                                                arp_target[i], slave->dev,
+                                                my_ip, arp_target_hw_addr,
+                                                slave->dev->dev_addr,
+                                                arp_target_hw_addr);
+                                        }
+
 				}
 			}
 		} else 
@@ -1544,11 +1554,17 @@
 			       the_delta_in_ticks) || 
 			     ((jiffies - slave->dev->last_rx) >= 
 			       the_delta_in_ticks) ) {
-				arp_send(ARPOP_REQUEST, ETH_P_ARP, 
-					 arp_target, slave->dev,
-					 my_ip, arp_target_hw_addr, 
-					 slave->dev->dev_addr, 
-					 arp_target_hw_addr); 
+                                int i;
+                                for ( i=0;
+                                      (i<MAX_ARP_IP_TARGETS) && arp_target[i];
+                                      i++) {
+                                        arp_send(ARPOP_REQUEST, ETH_P_ARP,
+                                                 arp_target[i], slave->dev,
+                                                 my_ip, arp_target_hw_addr,
+                                                 slave->dev->dev_addr,
+                                                 arp_target_hw_addr);
+                                }
+
 			}
 		} 
 
@@ -1563,9 +1579,15 @@
 		read_unlock(&bond->ptrlock);
 		slave = (slave_t *)bond;
 		while ((slave = slave->prev) != (slave_t *)bond)   {
-			arp_send(ARPOP_REQUEST, ETH_P_ARP, arp_target, 
-				 slave->dev, my_ip, arp_target_hw_addr, 
-				 slave->dev->dev_addr, arp_target_hw_addr); 
+                        int i;
+                        for ( i=0;
+                              (i<MAX_ARP_IP_TARGETS) && arp_target[i];
+                              i++) {
+                           arp_send(ARPOP_REQUEST, ETH_P_ARP, arp_target[i],
+                                    slave->dev, my_ip, arp_target_hw_addr,
+                                    slave->dev->dev_addr, arp_target_hw_addr);
+                        }
+
 		}
 	}
 	else {
@@ -1979,6 +2001,7 @@
 		memcpy(&my_ip, the_ip, 4);
 	}
 
+#if 0 /* no hw adresses should be cached permanently ! */
 	/* if we are sending arp packets and don't know 
 	   the target hw address, save it so we don't need 
 	   to use a broadcast address */
@@ -1989,6 +2012,7 @@
 		arp_target_hw_addr = kmalloc(ETH_ALEN, GFP_KERNEL);
 		memcpy(arp_target_hw_addr, eth_hdr->h_dest, ETH_ALEN);
 	}
+#endif
 
 	read_lock_irqsave(&bond->lock, flags);
 
@@ -2327,6 +2351,7 @@
 {
 	int no;
 	int err;
+	int i;
 
 	/* Find a name for this unit */
 	static struct net_device *dev_bond = NULL;
@@ -2369,12 +2394,17 @@
 		arp_interval = BOND_LINK_ARP_INTERV;
 	}
 
-	if (arp_ip_target) {
+        for (i=0 ; (i < MAX_ARP_IP_TARGETS) && arp_ip_target[i] ; i++ ) {
 		/* TODO: check and log bad ip address */
-		if (my_inet_aton(arp_ip_target, &arp_target) == 0)  {
+                if (my_inet_aton(arp_ip_target[i], &arp_target[i]) == 0) 
 			arp_interval = 0;
-		}
-	}
+                else {
+                        printk (KERN_INFO
+                                "bonding: arp_ip_target[%d]=%s.\n",
+                                 i,arp_ip_target[i]);
+                }
+        }
+
 
 	for (no = 0; no < max_bonds; no++) {
 		dev_bond->init = bond_init;

-----------------------end---cut-here----------------------