[PATCH] bonding: suppress duplicate packets

	Originally submitted by Kenzo Iwami; his original description is:

The current bonding driver receives duplicate packets when broadcast/
multicast packets are sent by other devices or packets are flooded by the
switch. In this patch, new flags are added in priv_flags of net_device
structure to let the bonding driver discard duplicate packets in
dev.c:skb_bond().

	Modified by Jay Vosburgh to change a define name, update some
comments, rearrange the new skb_bond() for clarity, clear all bonding
priv_flags on slave release, and update the driver version.

Signed-off-by: Kenzo Iwami <k-iwami@cj.jp.nec.com>
Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

6 files changed, 85 insertions, 27 deletions

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index bcf9f17daf0d..623c87a83615 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1040,6 +1040,10 @@ void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
         if ((bond->params.mode == BOND_MODE_TLB) ||
             (bond->params.mode == BOND_MODE_ALB)) {
                 bond_alb_handle_active_change(bond, new_active);
+                if (old_active)
+                        bond_set_slave_inactive_flags(old_active);
+                if (new_active)
+                        bond_set_slave_active_flags(new_active);
         } else {
                 bond->curr_active_slave = new_active;
         }
@@ -1443,15 +1447,16 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
 
         switch (bond->params.mode) {
         case BOND_MODE_ACTIVEBACKUP:
-                /* if we're in active-backup mode, we need one and only one active
-                 * interface. The backup interfaces will have their NOARP flag set
-                 * because we need them to be completely deaf and not to respond to
-                 * any ARP request on the network to avoid fooling a switch. Thus,
-                 * since we guarantee that curr_active_slave always point to the last
-                 * usable interface, we just have to verify this interface's flag.
+                /* if we're in active-backup mode, we need one and
+                 * only one active interface. The backup interfaces
+                 * will have their SLAVE_INACTIVE flag set because we
+                 * need them to be drop all packets. Thus, since we
+                 * guarantee that curr_active_slave always point to
+                 * the last usable interface, we just have to verify
+                 * this interface's flag.
                  */
                 if (((!bond->curr_active_slave) ||
-                     (bond->curr_active_slave->dev->flags & IFF_NOARP)) &&
+                     (bond->curr_active_slave->dev->priv_flags & IFF_SLAVE_INACTIVE)) &&
                     (new_slave->link != BOND_LINK_DOWN)) {
                         dprintk("This is the first active slave\n");
                         /* first slave or no active slave yet, and this link
@@ -1492,6 +1497,8 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
                          * is OK, so make this interface the active one
                          */
                         bond_change_active_slave(bond, new_slave);
+                } else {
+                        bond_set_slave_inactive_flags(new_slave);
                 }
                 break;
         default:
@@ -1724,13 +1731,8 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
         addr.sa_family = slave_dev->type;
         dev_set_mac_address(slave_dev, &addr);
 
-        /* restore the original state of the
-         * IFF_NOARP flag that might have been
-         * set by bond_set_slave_inactive_flags()
-         */
-        if ((slave->original_flags & IFF_NOARP) == 0) {
-                slave_dev->flags &= ~IFF_NOARP;
-        }
+        slave_dev->priv_flags &= ~(IFF_MASTER_8023AD | IFF_MASTER_ALB |
+                                   IFF_SLAVE_INACTIVE);
 
         kfree(slave);
 
@@ -1816,12 +1818,8 @@ static int bond_release_all(struct net_device *bond_dev)
                 addr.sa_family = slave_dev->type;
                 dev_set_mac_address(slave_dev, &addr);
 
-                /* restore the original state of the IFF_NOARP flag that might have
-                 * been set by bond_set_slave_inactive_flags()
-                 */
-                if ((slave->original_flags & IFF_NOARP) == 0) {
-                        slave_dev->flags &= ~IFF_NOARP;
-                }
+                slave_dev->priv_flags &= ~(IFF_MASTER_8023AD | IFF_MASTER_ALB |
+                                           IFF_SLAVE_INACTIVE);
 
                 kfree(slave);
 
@@ -4061,14 +4059,17 @@ void bond_set_mode_ops(struct bonding *bond, int mode)
                 bond_dev->hard_start_xmit = bond_xmit_broadcast;
                 break;
         case BOND_MODE_8023AD:
+                bond_set_master_3ad_flags(bond);
                 bond_dev->hard_start_xmit = bond_3ad_xmit_xor;
                 if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER34)
                         bond->xmit_hash_policy = bond_xmit_hash_policy_l34;
                 else
                         bond->xmit_hash_policy = bond_xmit_hash_policy_l2;
                 break;
-        case BOND_MODE_TLB:
         case BOND_MODE_ALB:
+                bond_set_master_alb_flags(bond);
+                /* FALLTHRU */
+        case BOND_MODE_TLB:
                 bond_dev->hard_start_xmit = bond_alb_xmit;
                 bond_dev->set_mac_address = bond_alb_set_mac_address;
                 break;
diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c
index 041bcc583557..5a9bd95884be 100644
--- a/drivers/net/bonding/bond_sysfs.c
+++ b/drivers/net/bonding/bond_sysfs.c
@@ -424,6 +424,12 @@ static ssize_t bonding_store_mode(struct class_device *cd, const char *buf, size
                 ret = -EINVAL;
                 goto out;
         } else {
+                if (bond->params.mode == BOND_MODE_8023AD)
+                        bond_unset_master_3ad_flags(bond);
+
+                if (bond->params.mode == BOND_MODE_ALB)
+                        bond_unset_master_alb_flags(bond);
+
                 bond->params.mode = new_value;
                 bond_set_mode_ops(bond, bond->params.mode);
                 printk(KERN_INFO DRV_NAME ": %s: setting mode to %s (%d).\n",
diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index 3dd78d048c3e..ce9dc9b4e2dc 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -22,8 +22,8 @@
 #include "bond_3ad.h"
 #include "bond_alb.h"
 
-#define DRV_VERSION     "3.0.1"
-#define DRV_RELDATE     "January 9, 2006"
+#define DRV_VERSION     "3.0.2"
+#define DRV_RELDATE     "February 21, 2006"
 #define DRV_NAME        "bonding"
 #define DRV_DESCRIPTION "Ethernet Channel Bonding Driver"
 
@@ -230,14 +230,37 @@ static inline struct bonding *bond_get_bond_by_slave(struct slave *slave)
 
 static inline void bond_set_slave_inactive_flags(struct slave *slave)
 {
-        slave->state = BOND_STATE_BACKUP;
-        slave->dev->flags |= IFF_NOARP;
+        struct bonding *bond = slave->dev->master->priv;
+        if (bond->params.mode != BOND_MODE_TLB &&
+            bond->params.mode != BOND_MODE_ALB)
+                slave->state = BOND_STATE_BACKUP;
+        slave->dev->priv_flags |= IFF_SLAVE_INACTIVE;
 }
 
 static inline void bond_set_slave_active_flags(struct slave *slave)
 {
         slave->state = BOND_STATE_ACTIVE;
-        slave->dev->flags &= ~IFF_NOARP;
+        slave->dev->priv_flags &= ~IFF_SLAVE_INACTIVE;
+}
+
+static inline void bond_set_master_3ad_flags(struct bonding *bond)
+{
+        bond->dev->priv_flags |= IFF_MASTER_8023AD;
+}
+
+static inline void bond_unset_master_3ad_flags(struct bonding *bond)
+{
+        bond->dev->priv_flags &= ~IFF_MASTER_8023AD;
+}
+
+static inline void bond_set_master_alb_flags(struct bonding *bond)
+{
+        bond->dev->priv_flags |= IFF_MASTER_ALB;
+}
+
+static inline void bond_unset_master_alb_flags(struct bonding *bond)
+{
+        bond->dev->priv_flags &= ~IFF_MASTER_ALB;
 }
 
 struct vlan_entry *bond_next_vlan(struct bonding *bond, struct vlan_entry *curr);
diff --git a/include/linux/if.h b/include/linux/if.h
index ce627d9092ef..12c6f6d157c3 100644
--- a/include/linux/if.h
+++ b/include/linux/if.h
@@ -52,6 +52,9 @@
 /* Private (from user) interface flags (netdevice->priv_flags). */
 #define IFF_802_1Q_VLAN 0x1             /* 802.1Q VLAN device.          */
 #define IFF_EBRIDGE     0x2             /* Ethernet bridging device.    */
+#define IFF_SLAVE_INACTIVE      0x4     /* bonding slave not the curr. active */
+#define IFF_MASTER_8023AD       0x8     /* bonding master, 802.3ad.     */
+#define IFF_MASTER_ALB  0x10            /* bonding master, balance-alb. */
 
 #define IF_GET_IFACE    0x0001          /* for querying only */
 #define IF_GET_PROTO    0x0002
diff --git a/include/linux/if_ether.h b/include/linux/if_ether.h
index 7a92c1ce1457..ab08f35cbc35 100644
--- a/include/linux/if_ether.h
+++ b/include/linux/if_ether.h
@@ -61,6 +61,7 @@
 #define ETH_P_8021Q     0x8100          /* 802.1Q VLAN Extended Header  */
 #define ETH_P_IPX       0x8137          /* IPX over DIX                 */
 #define ETH_P_IPV6      0x86DD          /* IPv6 over bluebook           */
+#define ETH_P_SLOW      0x8809          /* Slow Protocol. See 802.3ad 43B */
 #define ETH_P_WCCP      0x883E          /* Web-cache coordination protocol
                                          * defined in draft-wilson-wrec-wccp-v2-00.txt */
 #define ETH_P_PPP_DISC  0x8863          /* PPPoE discovery messages     */
diff --git a/net/core/dev.c b/net/core/dev.c
index 225e38ff57c4..ef56c035d44e 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1446,8 +1446,29 @@ static inline struct net_device *skb_bond(struct sk_buff *skb)
 {
         struct net_device *dev = skb->dev;
 
-        if (dev->master)
+        if (dev->master) {
+                /*
+                 * On bonding slaves other than the currently active
+                 * slave, suppress duplicates except for 802.3ad
+                 * ETH_P_SLOW and alb non-mcast/bcast.
+                 */
+                if (dev->priv_flags & IFF_SLAVE_INACTIVE) {
+                        if (dev->master->priv_flags & IFF_MASTER_ALB) {
+                                if (skb->pkt_type != PACKET_BROADCAST &&
+                                    skb->pkt_type != PACKET_MULTICAST)
+                                        goto keep;
+                        }
+
+                        if (dev->master->priv_flags & IFF_MASTER_8023AD &&
+                            skb->protocol == __constant_htons(ETH_P_SLOW))
+                                goto keep;
+                
+                        kfree_skb(skb);
+                        return NULL;
+                }
+keep:
                 skb->dev = dev->master;
+        }
 
         return dev;
 }
@@ -1591,6 +1612,9 @@ int netif_receive_skb(struct sk_buff *skb)
 
         orig_dev = skb_bond(skb);
 
+        if (!orig_dev)
+                return NET_RX_DROP;
+
         __get_cpu_var(netdev_rx_stat).total++;
 
         skb->h.raw = skb->nh.raw = skb->data;