patch-2.4.22 linux-2.4.22/drivers/net/bonding/bond_alb.c

Next file: linux-2.4.22/drivers/net/bonding/bond_alb.h
Previous file: linux-2.4.22/drivers/net/bonding/bond_3ad.h
Back to the patch index
Back to the overall index

diff -urN linux-2.4.21/drivers/net/bonding/bond_alb.c linux-2.4.22/drivers/net/bonding/bond_alb.c
@@ -0,0 +1,1576 @@
+/*
+ * Copyright(c) 1999 - 2003 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called LICENSE.
+ *
+ *
+ * Changes:
+ *
+ * 2003/06/25 - Shmulik Hen <shmulik.hen at intel dot com>
+ *	- Fixed signed/unsigned calculation errors that caused load sharing
+ *	  to collapse to one slave under very heavy UDP Tx stress.
+ */
+
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/pkt_sched.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/timer.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/if_bonding.h>
+#include <net/ipx.h>
+#include <net/arp.h>
+#include <asm/byteorder.h>
+#include "bonding.h"
+#include "bond_alb.h"
+
+
+#define ALB_TIMER_TICKS_PER_SEC	    10	/* should be a divisor of HZ */
+#define BOND_TLB_REBALANCE_INTERVAL 10	/* in seconds, periodic re-balancing
+					 * used for division - never set
+					 * to zero !!!
+					 */
+#define BOND_ALB_LP_INTERVAL	    1	/* in seconds periodic send of
+					 * learning packets to the switch
+					 */
+
+#define BOND_TLB_REBALANCE_TICKS (BOND_TLB_REBALANCE_INTERVAL \
+				  * ALB_TIMER_TICKS_PER_SEC)
+
+#define BOND_ALB_LP_TICKS (BOND_ALB_LP_INTERVAL \
+			   * ALB_TIMER_TICKS_PER_SEC)
+
+#define TLB_HASH_TABLE_SIZE 256	/* The size of the clients hash table.
+				 * Note that this value MUST NOT be smaller
+				 * because the key hash table BYTE wide !
+				 */
+
+
+#define TLB_NULL_INDEX		0xffffffff
+#define MAX_LP_RETRY		3
+
+/* rlb defs */
+#define RLB_HASH_TABLE_SIZE	256
+#define RLB_NULL_INDEX		0xffffffff
+#define RLB_UPDATE_DELAY	2*ALB_TIMER_TICKS_PER_SEC /* 2 seconds */
+#define RLB_ARP_BURST_SIZE	2
+#define RLB_UPDATE_RETRY	3	/* 3-ticks - must be smaller than the rlb
+					 * rebalance interval (5 min).
+					 */
+/* RLB_PROMISC_TIMEOUT = 10 sec equals the time that the current slave is
+ * promiscuous after failover
+ */
+#define RLB_PROMISC_TIMEOUT	10*ALB_TIMER_TICKS_PER_SEC
+
+#pragma pack(1)
+struct learning_pkt {
+	u8 mac_dst[ETH_ALEN];
+	u8 mac_src[ETH_ALEN];
+	u16 type;
+	u8 padding[ETH_ZLEN - (2*ETH_ALEN + 2)];
+};
+
+struct arp_pkt {
+	u16     hw_addr_space;
+	u16     prot_addr_space;
+	u8      hw_addr_len;
+	u8      prot_addr_len;
+	u16     op_code;
+	u8      mac_src[ETH_ALEN];	/* sender hardware address */
+	u32     ip_src;			/* sender IP address */
+	u8      mac_dst[ETH_ALEN];	/* target hardware address */
+	u32     ip_dst;			/* target IP address */
+};
+#pragma pack()
+
+/* Forward declaration */
+static void alb_send_learning_packets(struct slave *slave, u8 mac_addr[]);
+
+static inline u8
+_simple_hash(u8 *hash_start, int hash_size)
+{
+	int i;
+	u8 hash = 0;
+
+	for (i=0; i<hash_size; i++) {
+		hash ^= hash_start[i];
+	}
+
+	return hash;
+}
+
+/*********************** tlb specific functions ***************************/
+
+static inline void
+_lock_tx_hashtbl(struct bonding *bond)
+{
+	spin_lock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
+}
+
+static inline void
+_unlock_tx_hashtbl(struct bonding *bond)
+{
+	spin_unlock(&(BOND_ALB_INFO(bond).tx_hashtbl_lock));
+}
+
+/* Caller must hold tx_hashtbl lock */
+static inline void
+tlb_init_table_entry(struct bonding *bond, u8 index, u8 save_load)
+{
+	struct tlb_client_info *entry;
+
+	if (BOND_ALB_INFO(bond).tx_hashtbl == NULL) {
+		return;
+	}
+
+	entry = &(BOND_ALB_INFO(bond).tx_hashtbl[index]);
+	/* at end of cycle, save the load that was transmitted to the client
+	 * during the cycle, and set the tx_bytes counter to 0 for counting
+	 * the load during the next cycle
+	 */
+	if (save_load) {
+		entry->load_history = 1 + entry->tx_bytes /
+			BOND_TLB_REBALANCE_INTERVAL;
+		entry->tx_bytes = 0;
+	}
+	entry->tx_slave = NULL;
+	entry->next = TLB_NULL_INDEX;
+	entry->prev = TLB_NULL_INDEX;
+}
+
+static inline void
+tlb_init_slave(struct slave *slave)
+{
+	struct tlb_slave_info *slave_info = &(SLAVE_TLB_INFO(slave));
+
+	slave_info->load = 0;
+	slave_info->head = TLB_NULL_INDEX;
+}
+
+/* Caller must hold bond lock for read */
+static inline void
+tlb_clear_slave(struct bonding *bond, struct slave *slave, u8 save_load)
+{
+	struct tlb_client_info *tx_hash_table = NULL;
+	u32 index, next_index;
+
+	/* clear slave from tx_hashtbl */
+	_lock_tx_hashtbl(bond);
+	tx_hash_table = BOND_ALB_INFO(bond).tx_hashtbl;
+
+	if (tx_hash_table) {
+		index = SLAVE_TLB_INFO(slave).head;
+		while (index != TLB_NULL_INDEX) {
+			next_index = tx_hash_table[index].next;
+			tlb_init_table_entry(bond, index, save_load);
+			index = next_index;
+		}
+	}
+	_unlock_tx_hashtbl(bond);
+
+	tlb_init_slave(slave);
+}
+
+/* Must be called before starting the monitor timer */
+static int
+tlb_initialize(struct bonding *bond)
+{
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+	int i;
+	size_t size;
+
+#if(TLB_HASH_TABLE_SIZE != 256)
+	/* Key to the hash table is byte wide. Check the size! */
+	#error Hash Table size is wrong.
+#endif
+
+	spin_lock_init(&(bond_info->tx_hashtbl_lock));
+
+	_lock_tx_hashtbl(bond);
+	if (bond_info->tx_hashtbl != NULL) {
+		printk (KERN_ERR "%s: TLB hash table is not NULL\n",
+			bond->device->name);
+		_unlock_tx_hashtbl(bond);
+		return -1;
+	}
+
+	size = TLB_HASH_TABLE_SIZE * sizeof(struct tlb_client_info);
+	bond_info->tx_hashtbl = kmalloc(size, GFP_KERNEL);
+	if (bond_info->tx_hashtbl == NULL) {
+		printk (KERN_ERR "%s: Failed to allocate TLB hash table\n",
+			bond->device->name);
+		_unlock_tx_hashtbl(bond);
+		return -1;
+	}
+
+	memset(bond_info->tx_hashtbl, 0, size);
+	for (i=0; i<TLB_HASH_TABLE_SIZE; i++) {
+		tlb_init_table_entry(bond, i, 1);
+	}
+	_unlock_tx_hashtbl(bond);
+
+	return 0;
+}
+
+/* Must be called only after all slaves have been released */
+static void
+tlb_deinitialize(struct bonding *bond)
+{
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+
+	_lock_tx_hashtbl(bond);
+	if (bond_info->tx_hashtbl == NULL) {
+		_unlock_tx_hashtbl(bond);
+		return;
+	}
+	kfree(bond_info->tx_hashtbl);
+	bond_info->tx_hashtbl = NULL;
+	_unlock_tx_hashtbl(bond);
+}
+
+/* Caller must hold bond lock for read */
+static struct slave*
+tlb_get_least_loaded_slave(struct bonding *bond)
+{
+	struct slave *slave;
+	struct slave *least_loaded;
+	s64 curr_gap, max_gap;
+
+	/* Find the first enabled slave */
+	slave = bond_get_first_slave(bond);
+	while (slave) {
+		if (SLAVE_IS_OK(slave)) {
+			break;
+		}
+		slave = bond_get_next_slave(bond, slave);
+	}
+
+	if (!slave) {
+		return NULL;
+	}
+
+	least_loaded = slave;
+	max_gap = (s64)(slave->speed * 1000000) -
+			(s64)(SLAVE_TLB_INFO(slave).load * 8);
+
+	/* Find the slave with the largest gap */
+	slave = bond_get_next_slave(bond, slave);
+	while (slave) {
+		if (SLAVE_IS_OK(slave)) {
+			curr_gap = (s64)(slave->speed * 1000000) -
+					(s64)(SLAVE_TLB_INFO(slave).load * 8);
+			if (max_gap < curr_gap) {
+				least_loaded = slave;
+				max_gap = curr_gap;
+			}
+		}
+		slave = bond_get_next_slave(bond, slave);
+	}
+
+	return least_loaded;
+}
+
+/* Caller must hold bond lock for read */
+struct slave*
+tlb_choose_channel(struct bonding *bond, u32 hash_index, u32 skb_len)
+{
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+	struct tlb_client_info *hash_table = NULL;
+	struct slave *assigned_slave = NULL;
+
+	_lock_tx_hashtbl(bond);
+
+	hash_table = bond_info->tx_hashtbl;
+	if (hash_table == NULL) {
+		printk (KERN_ERR "%s: TLB hash table is NULL\n",
+			bond->device->name);
+		_unlock_tx_hashtbl(bond);
+		return NULL;
+	}
+
+	assigned_slave = hash_table[hash_index].tx_slave;
+	if (!assigned_slave) {
+		assigned_slave = tlb_get_least_loaded_slave(bond);
+
+		if (assigned_slave) {
+			struct tlb_slave_info *slave_info =
+				&(SLAVE_TLB_INFO(assigned_slave));
+			u32 next_index = slave_info->head;
+
+			hash_table[hash_index].tx_slave = assigned_slave;
+			hash_table[hash_index].next = next_index;
+			hash_table[hash_index].prev = TLB_NULL_INDEX;
+
+			if (next_index != TLB_NULL_INDEX) {
+				hash_table[next_index].prev = hash_index;
+			}
+
+			slave_info->head = hash_index;
+			slave_info->load +=
+				hash_table[hash_index].load_history;
+		}
+	}
+
+	if (assigned_slave) {
+		hash_table[hash_index].tx_bytes += skb_len;
+	}
+
+	_unlock_tx_hashtbl(bond);
+
+	return assigned_slave;
+}
+
+/*********************** rlb specific functions ***************************/
+static inline void
+_lock_rx_hashtbl(struct bonding *bond)
+{
+	spin_lock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
+}
+
+static inline void
+_unlock_rx_hashtbl(struct bonding *bond)
+{
+	spin_unlock(&(BOND_ALB_INFO(bond).rx_hashtbl_lock));
+}
+
+/* when an ARP REPLY is received from a client update its info
+ * in the rx_hashtbl
+ */
+static void
+rlb_update_entry_from_arp(struct bonding *bond, struct arp_pkt *arp)
+{
+	u32 hash_index;
+	struct rlb_client_info *client_info = NULL;
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+
+	_lock_rx_hashtbl(bond);
+
+	if (bond_info->rx_hashtbl == NULL) {
+		_unlock_rx_hashtbl(bond);
+		return;
+	}
+	hash_index = _simple_hash((u8*)&(arp->ip_src), 4);
+	client_info = &(bond_info->rx_hashtbl[hash_index]);
+
+	if ((client_info->assigned) &&
+	    (client_info->ip_src == arp->ip_dst) &&
+	    (client_info->ip_dst == arp->ip_src)) {
+
+		/* update the clients MAC address */
+		memcpy(client_info->mac_dst, arp->mac_src, ETH_ALEN);
+		client_info->ntt = 1;
+		bond_info->rx_ntt = 1;
+	}
+
+	_unlock_rx_hashtbl(bond);
+}
+
+static int
+rlb_arp_recv(struct sk_buff *skb,
+	     struct net_device *dev,
+	     struct packet_type* ptype)
+{
+	struct bonding *bond = (struct bonding *)dev->priv;
+	int ret = NET_RX_DROP;
+	struct arp_pkt *arp = (struct arp_pkt *)skb->data;
+
+	if (!(dev->flags & IFF_MASTER)) {
+		goto out;
+	}
+
+	if (!arp) {
+		printk(KERN_ERR "Packet has no ARP data\n");
+		goto out;
+	}
+
+	if (skb->len < sizeof(struct arp_pkt)) {
+		printk(KERN_ERR "Packet is too small to be an ARP\n");
+		goto out;
+	}
+
+	if (arp->op_code == htons(ARPOP_REPLY)) {
+		/* update rx hash table for this ARP */
+		rlb_update_entry_from_arp(bond, arp);
+		BOND_PRINT_DBG(("Server received an ARP Reply from client"));
+	}
+
+	ret = NET_RX_SUCCESS;
+
+out:
+	dev_kfree_skb(skb);
+
+	return ret;
+}
+
+/* Caller must hold bond lock for read */
+static struct slave*
+rlb_next_rx_slave(struct bonding *bond)
+{
+	struct slave *rx_slave = NULL, *slave = NULL;
+	unsigned int i = 0;
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+
+	slave = bond_info->next_rx_slave;
+	if (slave == NULL) {
+		slave = bond->next;
+	}
+
+	/* this loop uses the circular linked list property of the
+	 * slave's list to go through all slaves
+	 */
+	for (i = 0; i < bond->slave_cnt; i++, slave = slave->next) {
+
+		if (SLAVE_IS_OK(slave)) {
+			if (!rx_slave) {
+				rx_slave = slave;
+			}
+			else if (slave->speed > rx_slave->speed) {
+				rx_slave = slave;
+			}
+		}
+	}
+
+	if (rx_slave) {
+		bond_info->next_rx_slave = rx_slave->next;
+	}
+
+	return rx_slave;
+}
+
+/* teach the switch the mac of a disabled slave
+ * on the primary for fault tolerance
+ *
+ * Caller must hold bond->ptrlock for write or bond lock for write
+ */
+static void
+rlb_teach_disabled_mac_on_primary(struct bonding *bond, u8 addr[])
+{
+	if (!bond->current_slave) {
+		return;
+	}
+	if (!bond->alb_info.primary_is_promisc) {
+		bond->alb_info.primary_is_promisc = 1;
+		dev_set_promiscuity(bond->current_slave->dev, 1);
+	}
+	bond->alb_info.rlb_promisc_timeout_counter = 0;
+
+	alb_send_learning_packets(bond->current_slave, addr);
+}
+
+/* slave being removed should not be active at this point
+ *
+ * Caller must hold bond lock for read
+ */
+static void
+rlb_clear_slave(struct bonding *bond, struct slave *slave)
+{
+	struct rlb_client_info *rx_hash_table = NULL;
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+	u8 mac_bcast[ETH_ALEN] = {0xff,0xff,0xff,0xff,0xff,0xff};
+	u32 index, next_index;
+
+	/* clear slave from rx_hashtbl */
+	_lock_rx_hashtbl(bond);
+	rx_hash_table = bond_info->rx_hashtbl;
+
+	if (rx_hash_table == NULL) {
+		_unlock_rx_hashtbl(bond);
+		return;
+	}
+
+	index = bond_info->rx_hashtbl_head;
+	for (; index != RLB_NULL_INDEX; index = next_index) {
+		next_index = rx_hash_table[index].next;
+
+		if (rx_hash_table[index].slave == slave) {
+			struct slave *assigned_slave = rlb_next_rx_slave(bond);
+
+			if (assigned_slave) {
+				rx_hash_table[index].slave = assigned_slave;
+				if (memcmp(rx_hash_table[index].mac_dst,
+					   mac_bcast, ETH_ALEN)) {
+					bond_info->rx_hashtbl[index].ntt = 1;
+					bond_info->rx_ntt = 1;
+					/* A slave has been removed from the
+					 * table because it is either disabled
+					 * or being released. We must retry the
+					 * update to avoid clients from not
+					 * being updated & disconnecting when
+					 * there is stress
+					 */
+					bond_info->rlb_update_retry_counter =
+						RLB_UPDATE_RETRY;
+				}
+			} else {  /* there is no active slave */
+				rx_hash_table[index].slave = NULL;
+			}
+		}
+	}
+
+	_unlock_rx_hashtbl(bond);
+
+	write_lock(&bond->ptrlock);
+	if (slave != bond->current_slave) {
+		rlb_teach_disabled_mac_on_primary(bond, slave->dev->dev_addr);
+	}
+	write_unlock(&bond->ptrlock);
+}
+
+static void
+rlb_update_client(struct rlb_client_info *client_info)
+{
+	int i = 0;
+
+	if (client_info->slave == NULL) {
+		return;
+	}
+
+	for (i=0; i<RLB_ARP_BURST_SIZE; i++) {
+		arp_send(ARPOP_REPLY, ETH_P_ARP,
+			 client_info->ip_dst,
+			 client_info->slave->dev,
+			 client_info->ip_src,
+			 client_info->mac_dst,
+			 client_info->slave->dev->dev_addr,
+			 client_info->mac_dst);
+	}
+}
+
+/* sends ARP REPLIES that update the clients that need updating */
+static void
+rlb_update_rx_clients(struct bonding *bond)
+{
+	u32 hash_index;
+	struct rlb_client_info *client_info = NULL;
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+
+	_lock_rx_hashtbl(bond);
+
+	if (bond_info->rx_hashtbl == NULL) {
+		_unlock_rx_hashtbl(bond);
+		return;
+	}
+
+	hash_index = bond_info->rx_hashtbl_head;
+	for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
+		client_info = &(bond_info->rx_hashtbl[hash_index]);
+		if (client_info->ntt) {
+			rlb_update_client(client_info);
+			if (bond_info->rlb_update_retry_counter == 0) {
+				client_info->ntt = 0;
+			}
+		}
+	}
+
+	/* do not update the entries again untill this counter is zero so that
+	 * not to confuse the clients.
+	 */
+	bond_info->rlb_update_delay_counter = RLB_UPDATE_DELAY;
+
+	_unlock_rx_hashtbl(bond);
+}
+
+/* The slave was assigned a new mac address - update the clients */
+static void
+rlb_req_update_slave_clients(struct bonding *bond, struct slave *slave)
+{
+	u32 hash_index;
+	u8 ntt = 0;
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+	u8 mac_bcast[ETH_ALEN] = {0xff,0xff,0xff,0xff,0xff,0xff};
+	struct rlb_client_info* client_info = NULL;
+
+	_lock_rx_hashtbl(bond);
+
+	if (bond_info->rx_hashtbl == NULL) {
+		_unlock_rx_hashtbl(bond);
+		return;
+	}
+
+	hash_index = bond_info->rx_hashtbl_head;
+	for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
+		client_info = &(bond_info->rx_hashtbl[hash_index]);
+
+		if ((client_info->slave == slave) &&
+		    memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
+			client_info->ntt = 1;
+			ntt = 1;
+		}
+	}
+
+	// update the team's flag only after the whole iteration
+	if (ntt) {
+		bond_info->rx_ntt = 1;
+		//fasten the change
+		bond_info->rlb_update_retry_counter = RLB_UPDATE_RETRY;
+	}
+
+	_unlock_rx_hashtbl(bond);
+}
+
+/* mark all clients using src_ip to be updated */
+static void
+rlb_req_update_subnet_clients(struct bonding *bond, u32 src_ip)
+{
+	u32 hash_index;
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+	u8 mac_bcast[ETH_ALEN] = {0xff,0xff,0xff,0xff,0xff,0xff};
+	struct rlb_client_info *client_info = NULL;
+
+	_lock_rx_hashtbl(bond);
+
+	if (bond_info->rx_hashtbl == NULL) {
+		_unlock_rx_hashtbl(bond);
+		return;
+	}
+
+	hash_index = bond_info->rx_hashtbl_head;
+	for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
+		client_info = &(bond_info->rx_hashtbl[hash_index]);
+
+		if (!client_info->slave) {
+			printk(KERN_ERR "Bonding: Error: found a client with no"
+			       " channel in the client's hash table\n");
+			continue;
+		}
+		/*update all clients using this src_ip, that are not assigned
+		 * to the team's address (current_slave) and have a known
+		 * unicast mac address.
+		 */
+		if ((client_info->ip_src == src_ip) &&
+		    memcmp(client_info->slave->dev->dev_addr,
+			   bond->device->dev_addr, ETH_ALEN) &&
+		    memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
+			client_info->ntt = 1;
+			bond_info->rx_ntt = 1;
+		}
+	}
+
+	_unlock_rx_hashtbl(bond);
+}
+
+/* Caller must hold both bond and ptr locks for read */
+struct slave*
+rlb_choose_channel(struct bonding *bond, struct arp_pkt *arp)
+{
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+	struct rlb_client_info *client_info = NULL;
+	u32 hash_index = 0;
+	struct slave *assigned_slave = NULL;
+	u8 mac_bcast[ETH_ALEN] = {0xff,0xff,0xff,0xff,0xff,0xff};
+
+	_lock_rx_hashtbl(bond);
+
+	if (bond_info->rx_hashtbl == NULL) {
+		_unlock_rx_hashtbl(bond);
+		return NULL;
+	}
+
+	hash_index = _simple_hash((u8 *)&arp->ip_dst, 4);
+	client_info = &(bond_info->rx_hashtbl[hash_index]);
+
+	if (client_info->assigned == 1) {
+		if ((client_info->ip_src == arp->ip_src) &&
+		    (client_info->ip_dst == arp->ip_dst)) {
+			/* the entry is already assigned to this client */
+
+			if (memcmp(arp->mac_dst, mac_bcast, ETH_ALEN)) {
+				/* update mac address from arp */
+				memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
+			}
+
+			assigned_slave = client_info->slave;
+			if (assigned_slave) {
+				_unlock_rx_hashtbl(bond);
+				return assigned_slave;
+			}
+		} else {
+			/* the entry is already assigned to some other client,
+			 * move the old client to primary (current_slave) so
+			 * that the new client can be assigned to this entry.
+			 */
+			if (bond->current_slave &&
+			    client_info->slave != bond->current_slave) {
+				client_info->slave = bond->current_slave;
+				rlb_update_client(client_info);
+			}
+		}
+	}
+	/* assign a new slave */
+	assigned_slave = rlb_next_rx_slave(bond);
+
+	if (assigned_slave) {
+		client_info->ip_src = arp->ip_src;
+		client_info->ip_dst = arp->ip_dst;
+		/* arp->mac_dst is broadcast for arp reqeusts.
+		 * will be updated with clients actual unicast mac address
+		 * upon receiving an arp reply.
+		 */
+		memcpy(client_info->mac_dst, arp->mac_dst, ETH_ALEN);
+		client_info->slave = assigned_slave;
+
+		if (memcmp(client_info->mac_dst, mac_bcast, ETH_ALEN)) {
+			client_info->ntt = 1;
+			bond->alb_info.rx_ntt = 1;
+		}
+		else {
+			client_info->ntt = 0;
+		}
+
+		if (!client_info->assigned) {
+			u32 prev_tbl_head = bond_info->rx_hashtbl_head;
+			bond_info->rx_hashtbl_head = hash_index;
+			client_info->next = prev_tbl_head;
+			if (prev_tbl_head != RLB_NULL_INDEX) {
+				bond_info->rx_hashtbl[prev_tbl_head].prev =
+					hash_index;
+			}
+			client_info->assigned = 1;
+		}
+	}
+
+	_unlock_rx_hashtbl(bond);
+
+	return assigned_slave;
+}
+
+/* chooses (and returns) transmit channel for arp reply
+ * does not choose channel for other arp types since they are
+ * sent on the current_slave
+ */
+static struct slave*
+rlb_arp_xmit(struct sk_buff *skb, struct bonding *bond)
+{
+	struct arp_pkt *arp = (struct arp_pkt *)skb->nh.raw;
+	struct slave *tx_slave = NULL;
+
+	if (arp->op_code == __constant_htons(ARPOP_REPLY)) {
+		/* the arp must be sent on the selected
+		* rx channel
+		*/
+		tx_slave = rlb_choose_channel(bond, arp);
+		if (tx_slave) {
+			memcpy(arp->mac_src,tx_slave->dev->dev_addr, ETH_ALEN);
+		}
+		BOND_PRINT_DBG(("Server sent ARP Reply packet"));
+	} else if (arp->op_code == __constant_htons(ARPOP_REQUEST)) {
+
+		/* Create an entry in the rx_hashtbl for this client as a
+		 * place holder.
+		 * When the arp reply is received the entry will be updated
+		 * with the correct unicast address of the client.
+		 */
+		rlb_choose_channel(bond, arp);
+
+		/* The ARP relpy packets must be delayed so that
+		 * they can cancel out the influence of the ARP request.
+		 */
+		bond->alb_info.rlb_update_delay_counter = RLB_UPDATE_DELAY;
+
+		/* arp requests are broadcast and are sent on the primary
+		 * the arp request will collapse all clients on the subnet to
+		 * the primary slave. We must register these clients to be
+		 * updated with their assigned mac.
+		 */
+		rlb_req_update_subnet_clients(bond, arp->ip_src);
+		BOND_PRINT_DBG(("Server sent ARP Request packet"));
+	}
+
+	return tx_slave;
+}
+
+/* Caller must hold bond lock for read */
+static void
+rlb_rebalance(struct bonding *bond)
+{
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+	struct slave *assigned_slave = NULL;
+	u32 hash_index;
+	struct rlb_client_info *client_info = NULL;
+	u8 ntt = 0;
+
+	_lock_rx_hashtbl(bond);
+
+	if (bond_info->rx_hashtbl == NULL) {
+		_unlock_rx_hashtbl(bond);
+		return;
+	}
+
+	hash_index = bond_info->rx_hashtbl_head;
+	for (; hash_index != RLB_NULL_INDEX; hash_index = client_info->next) {
+		client_info = &(bond_info->rx_hashtbl[hash_index]);
+		assigned_slave = rlb_next_rx_slave(bond);
+		if (assigned_slave && (client_info->slave != assigned_slave)){
+			client_info->slave = assigned_slave;
+			client_info->ntt = 1;
+			ntt = 1;
+		}
+	}
+
+	/* update the team's flag only after the whole iteration */
+	if (ntt) {
+		bond_info->rx_ntt = 1;
+	}
+	_unlock_rx_hashtbl(bond);
+}
+
+/* Caller must hold rx_hashtbl lock */
+static inline void
+rlb_init_table_entry(struct rlb_client_info *entry)
+{
+	entry->next = RLB_NULL_INDEX;
+	entry->prev = RLB_NULL_INDEX;
+	entry->assigned = 0;
+	entry->ntt = 0;
+}
+
+static int
+rlb_initialize(struct bonding *bond)
+{
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+	struct packet_type *pk_type = &(BOND_ALB_INFO(bond).rlb_pkt_type);
+	int i;
+	size_t size;
+
+	spin_lock_init(&(bond_info->rx_hashtbl_lock));
+
+	_lock_rx_hashtbl(bond);
+	if (bond_info->rx_hashtbl != NULL) {
+		printk (KERN_ERR "%s: RLB hash table is not NULL\n",
+			bond->device->name);
+		_unlock_rx_hashtbl(bond);
+		return -1;
+	}
+
+	size = RLB_HASH_TABLE_SIZE * sizeof(struct rlb_client_info);
+	bond_info->rx_hashtbl = kmalloc(size, GFP_KERNEL);
+	if (bond_info->rx_hashtbl == NULL) {
+		printk (KERN_ERR "%s: Failed to allocate"
+			" RLB hash table\n", bond->device->name);
+		_unlock_rx_hashtbl(bond);
+		return -1;
+	}
+
+	bond_info->rx_hashtbl_head = RLB_NULL_INDEX;
+
+	for (i=0; i<RLB_HASH_TABLE_SIZE; i++) {
+		rlb_init_table_entry(bond_info->rx_hashtbl + i);
+	}
+	_unlock_rx_hashtbl(bond);
+
+	/* register to receive ARPs */
+
+	/*initialize packet type*/
+	pk_type->type = __constant_htons(ETH_P_ARP);
+	pk_type->dev = bond->device;
+	pk_type->func = rlb_arp_recv;
+	pk_type->data = (void*)1;  /* understand shared skbs */
+
+	dev_add_pack(pk_type);
+
+	return 0;
+}
+
+static void
+rlb_deinitialize(struct bonding *bond)
+{
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+
+	dev_remove_pack(&(bond_info->rlb_pkt_type));
+
+	_lock_rx_hashtbl(bond);
+	if (bond_info->rx_hashtbl == NULL) {
+		_unlock_rx_hashtbl(bond);
+		return;
+	}
+	kfree(bond_info->rx_hashtbl);
+	bond_info->rx_hashtbl = NULL;
+	_unlock_rx_hashtbl(bond);
+}
+
+/*********************** tlb/rlb shared functions *********************/
+
+static void
+alb_send_learning_packets(struct slave *slave, u8 mac_addr[])
+{
+	struct sk_buff *skb = NULL;
+	struct learning_pkt pkt;
+	char *data = NULL;
+	int i;
+	unsigned int size = sizeof(struct learning_pkt);
+
+	memset(&pkt, 0, size);
+	memcpy(pkt.mac_dst, mac_addr, ETH_ALEN);
+	memcpy(pkt.mac_src, mac_addr, ETH_ALEN);
+	pkt.type = __constant_htons(ETH_P_LOOP);
+
+	for (i=0; i < MAX_LP_RETRY; i++) {
+		skb = NULL;
+		skb = dev_alloc_skb(size);
+		if (!skb) {
+			return;
+		}
+
+		data = skb_put(skb, size);
+		memcpy(data, &pkt, size);
+		skb->mac.raw = data;
+		skb->nh.raw = data + ETH_HLEN;
+		skb->protocol = pkt.type;
+		skb->priority = TC_PRIO_CONTROL;
+		skb->dev = slave->dev;
+		dev_queue_xmit(skb);
+	}
+
+}
+
+/* hw is a boolean parameter that determines whether we should try and
+ * set the hw address of the hw as well as the hw address of the net_device
+ */
+static int
+alb_set_mac_addr(struct slave *slave, u8 addr[], int hw)
+{
+	struct net_device *dev = NULL;
+	struct sockaddr s_addr;
+
+	dev = slave->dev;
+
+	if (!hw) {
+		memcpy(dev->dev_addr, addr, ETH_ALEN);
+		return 0;
+	}
+
+	/* for rlb each slave must have a unique hw mac addresses so that */
+	/* each slave will receive packets destined to a different mac */
+	memcpy(s_addr.sa_data, addr, ETH_ALEN);
+	s_addr.sa_family = dev->type;
+	if (dev->set_mac_address(dev, &s_addr)) {
+		printk(KERN_DEBUG "bonding: Error: alb_set_mac_addr:"
+				  " dev->set_mac_address of dev %s failed!"
+				  " ALB mode requires that the base driver"
+				  " support setting the hw address also when"
+				  " the network device's interface is open\n",
+				  dev->name);
+		return -EOPNOTSUPP;
+	}
+	return 0;
+}
+
+/* Caller must hold bond lock for write or ptrlock for write*/
+static void
+alb_swap_mac_addr(struct bonding *bond,
+		  struct slave *slave1,
+		  struct slave *slave2)
+{
+	u8 tmp_mac_addr[ETH_ALEN];
+	struct slave *disabled_slave = NULL;
+	u8 slaves_state_differ;
+
+	slaves_state_differ = (SLAVE_IS_OK(slave1) != SLAVE_IS_OK(slave2));
+
+	memcpy(tmp_mac_addr, slave1->dev->dev_addr, ETH_ALEN);
+	alb_set_mac_addr(slave1, slave2->dev->dev_addr, bond->alb_info.rlb_enabled);
+	alb_set_mac_addr(slave2, tmp_mac_addr, bond->alb_info.rlb_enabled);
+
+	/* fasten the change in the switch */
+	if (SLAVE_IS_OK(slave1)) {
+		alb_send_learning_packets(slave1, slave1->dev->dev_addr);
+		if (bond->alb_info.rlb_enabled) {
+			/* inform the clients that the mac address
+			 * has changed
+			 */
+			rlb_req_update_slave_clients(bond, slave1);
+		}
+	}
+	else {
+		disabled_slave = slave1;
+	}
+
+	if (SLAVE_IS_OK(slave2)) {
+		alb_send_learning_packets(slave2, slave2->dev->dev_addr);
+		if (bond->alb_info.rlb_enabled) {
+			/* inform the clients that the mac address
+			 * has changed
+			 */
+			rlb_req_update_slave_clients(bond, slave2);
+		}
+	}
+	else {
+		disabled_slave = slave2;
+	}
+
+	if (bond->alb_info.rlb_enabled && slaves_state_differ) {
+			/* A disabled slave was assigned an active mac addr */
+			rlb_teach_disabled_mac_on_primary(bond,
+				disabled_slave->dev->dev_addr);
+	}
+}
+
+/**
+ * alb_change_hw_addr_on_detach
+ * @bond: bonding we're working on
+ * @slave: the slave that was just detached
+ *
+ * We assume that @slave was already detached from the slave list.
+ *
+ * If @slave's permanent hw address is different both from its current
+ * address and from @bond's address, then somewhere in the bond there's
+ * a slave that has @slave's permanet address as its current address.
+ * We'll make sure that that slave no longer uses @slave's permanent address.
+ *
+ * Caller must hold bond lock
+ */
+static void
+alb_change_hw_addr_on_detach(struct bonding *bond, struct slave *slave)
+{
+	struct slave *tmp_slave;
+	int perm_curr_diff;
+	int perm_bond_diff;
+
+	perm_curr_diff = memcmp(slave->perm_hwaddr,
+				slave->dev->dev_addr,
+				ETH_ALEN);
+	perm_bond_diff = memcmp(slave->perm_hwaddr,
+				bond->device->dev_addr,
+				ETH_ALEN);
+	if (perm_curr_diff && perm_bond_diff) {
+		tmp_slave = bond_get_first_slave(bond);
+		while (tmp_slave) {
+			if (!memcmp(slave->perm_hwaddr,
+				   tmp_slave->dev->dev_addr,
+				   ETH_ALEN)) {
+				break;
+			}
+			tmp_slave = bond_get_next_slave(bond, tmp_slave);
+		}
+
+		if (tmp_slave) {
+			alb_swap_mac_addr(bond, slave, tmp_slave);
+		}
+	}
+}
+
+/**
+ * alb_handle_addr_collision_on_attach
+ * @bond: bonding we're working on
+ * @slave: the slave that was just attached
+ *
+ * checks uniqueness of slave's mac address and handles the case the
+ * new slave uses the bonds mac address.
+ *
+ * If the permanent hw address of @slave is @bond's hw address, we need to
+ * find a different hw address to give @slave, that isn't in use by any other
+ * slave in the bond. This address must be, of course, one of the premanent
+ * addresses of the other slaves.
+ *
+ * We go over the slave list, and for each slave there we compare its
+ * permanent hw address with the current address of all the other slaves.
+ * If no match was found, then we've found a slave with a permanent address
+ * that isn't used by any other slave in the bond, so we can assign it to
+ * @slave.
+ *
+ * assumption: this function is called before @slave is attached to the
+ * 	       bond slave list.
+ *
+ * caller must hold the bond lock for write since the mac addresses are compared
+ * and may be swapped.
+ */
+static int
+alb_handle_addr_collision_on_attach(struct bonding *bond, struct slave *slave)
+{
+	struct slave *tmp_slave1, *tmp_slave2;
+
+	if (bond->slave_cnt == 0) {
+		/* this is the first slave */
+		return 0;
+	}
+
+	/* if slave's mac address differs from bond's mac address
+	 * check uniqueness of slave's mac address against the other
+	 * slaves in the bond.
+	 */
+	if (memcmp(slave->perm_hwaddr, bond->device->dev_addr, ETH_ALEN)) {
+		tmp_slave1 = bond_get_first_slave(bond);
+		for (; tmp_slave1; tmp_slave1 = bond_get_next_slave(bond, tmp_slave1)) {
+			if (!memcmp(tmp_slave1->dev->dev_addr, slave->dev->dev_addr,
+				    ETH_ALEN)) {
+				break;
+			}
+		}
+		if (tmp_slave1) {
+			/* a slave was found that is using the mac address
+			 * of the new slave
+			 */
+			printk(KERN_ERR "bonding: Warning: the hw address "
+			       "of slave %s is not unique - cannot enslave it!"
+			       , slave->dev->name);
+			return -EINVAL;
+		}
+		return 0;
+	}
+
+	/* the slave's address is equal to the address of the bond
+	 * search for a spare address in the bond for this slave.
+	 */
+	tmp_slave1 = bond_get_first_slave(bond);
+	for (; tmp_slave1; tmp_slave1 = bond_get_next_slave(bond, tmp_slave1)) {
+
+		tmp_slave2 = bond_get_first_slave(bond);
+		for (; tmp_slave2; tmp_slave2 = bond_get_next_slave(bond, tmp_slave2)) {
+
+			if (!memcmp(tmp_slave1->perm_hwaddr,
+				    tmp_slave2->dev->dev_addr,
+				    ETH_ALEN)) {
+
+				break;
+			}
+		}
+
+		if (!tmp_slave2) {
+			/* no slave has tmp_slave1's perm addr
+			 * as its curr addr
+			 */
+			break;
+		}
+	}
+
+	if (tmp_slave1) {
+		alb_set_mac_addr(slave, tmp_slave1->perm_hwaddr,
+				 bond->alb_info.rlb_enabled);
+
+		printk(KERN_WARNING "bonding: Warning: the hw address "
+		       "of slave %s is in use by the bond; "
+		       "giving it the hw address of %s\n",
+		       slave->dev->name, tmp_slave1->dev->name);
+	} else {
+		printk(KERN_CRIT "bonding: Error: the hw address "
+		       "of slave %s is in use by the bond; "
+		       "couldn't find a slave with a free hw "
+		       "address to give it (this should not have "
+		       "happened)\n", slave->dev->name);
+		return -EFAULT;
+	}
+
+	return 0;
+}
+
+/************************ exported alb funcions ************************/
+
+int
+bond_alb_initialize(struct bonding *bond, int rlb_enabled)
+{
+	int res;
+
+	res = tlb_initialize(bond);
+	if (res) {
+		return res;
+	}
+
+	if (rlb_enabled) {
+		bond->alb_info.rlb_enabled = 1;
+		/* initialize rlb */
+		res = rlb_initialize(bond);
+		if (res) {
+			tlb_deinitialize(bond);
+			return res;
+		}
+	}
+
+	return 0;
+}
+
+void
+bond_alb_deinitialize(struct bonding *bond)
+{
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+
+	tlb_deinitialize(bond);
+
+	if (bond_info->rlb_enabled) {
+		rlb_deinitialize(bond);
+	}
+}
+
+int
+bond_alb_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct bonding *bond = (struct bonding *) dev->priv;
+	struct ethhdr *eth_data = (struct ethhdr *)skb->data;
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+	struct slave *tx_slave = NULL;
+	char do_tx_balance = 1;
+	int hash_size = 0;
+	u32 hash_index = 0;
+	u8 *hash_start = NULL;
+	u8 mac_bcast[ETH_ALEN] = {0xff,0xff,0xff,0xff,0xff,0xff};
+
+	if (!IS_UP(dev)) { /* bond down */
+		dev_kfree_skb(skb);
+		return 0;
+	}
+
+	/* make sure that the current_slave and the slaves list do
+	 * not change during tx
+	 */
+	read_lock(&bond->lock);
+
+	if (bond->slave_cnt == 0) {
+		/* no suitable interface, frame not sent */
+		dev_kfree_skb(skb);
+		read_unlock(&bond->lock);
+		return 0;
+	}
+
+	read_lock(&bond->ptrlock);
+
+	switch (ntohs(skb->protocol)) {
+	case ETH_P_IP:
+		if ((memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) ||
+		    (skb->nh.iph->daddr == 0xffffffff)) {
+			do_tx_balance = 0;
+			break;
+		}
+		hash_start = (char*)&(skb->nh.iph->daddr);
+		hash_size = 4;
+		break;
+
+	case ETH_P_IPV6:
+		if (memcmp(eth_data->h_dest, mac_bcast, ETH_ALEN) == 0) {
+			do_tx_balance = 0;
+			break;
+		}
+
+		hash_start = (char*)&(skb->nh.ipv6h->daddr);
+		hash_size = 16;
+		break;
+
+	case ETH_P_IPX:
+		if (skb->nh.ipxh->ipx_checksum !=
+		    __constant_htons(IPX_NO_CHECKSUM)) {
+			/* something is wrong with this packet */
+			do_tx_balance = 0;
+			break;
+		}
+
+		if (skb->nh.ipxh->ipx_type !=
+		    __constant_htons(IPX_TYPE_NCP)) {
+			/* The only protocol worth balancing in
+			 * this family since it has an "ARP" like
+			 * mechanism
+			 */
+			do_tx_balance = 0;
+			break;
+		}
+
+		hash_start = (char*)eth_data->h_dest;
+		hash_size = ETH_ALEN;
+		break;
+
+	case ETH_P_ARP:
+		do_tx_balance = 0;
+		if (bond_info->rlb_enabled) {
+			tx_slave = rlb_arp_xmit(skb, bond);
+		}
+		break;
+
+	default:
+		do_tx_balance = 0;
+		break;
+	}
+
+	if (do_tx_balance) {
+		hash_index = _simple_hash(hash_start, hash_size);
+		tx_slave = tlb_choose_channel(bond, hash_index, skb->len);
+	}
+
+	if (!tx_slave) {
+		/* unbalanced or unassigned, send through primary */
+		tx_slave = bond->current_slave;
+		bond_info->unbalanced_load += skb->len;
+	}
+
+	if (tx_slave && SLAVE_IS_OK(tx_slave)) {
+		skb->dev = tx_slave->dev;
+		if (tx_slave != bond->current_slave) {
+			memcpy(eth_data->h_source,
+				tx_slave->dev->dev_addr,
+				ETH_ALEN);
+		}
+		dev_queue_xmit(skb);
+	} else {
+		/* no suitable interface, frame not sent */
+		if (tx_slave) {
+			tlb_clear_slave(bond, tx_slave, 0);
+		}
+		dev_kfree_skb(skb);
+	}
+
+	read_unlock(&bond->ptrlock);
+	read_unlock(&bond->lock);
+	return 0;
+}
+
+void
+bond_alb_monitor(struct bonding *bond)
+{
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+	struct slave *slave = NULL;
+
+	read_lock(&bond->lock);
+
+	if ((bond->slave_cnt == 0) || !(bond->device->flags & IFF_UP)) {
+		bond_info->tx_rebalance_counter = 0;
+		bond_info->lp_counter = 0;
+		goto out;
+	}
+
+	bond_info->tx_rebalance_counter++;
+	bond_info->lp_counter++;
+
+	/* send learning packets */
+	if (bond_info->lp_counter >= BOND_ALB_LP_TICKS) {
+		/* change of current_slave involves swapping of mac addresses.
+		 * in order to avoid this swapping from happening while
+		 * sending the learning packets, the ptrlock must be held for
+		 * read.
+		 */
+		read_lock(&bond->ptrlock);
+		slave = bond_get_first_slave(bond);
+		while (slave) {
+			alb_send_learning_packets(slave,slave->dev->dev_addr);
+			slave = bond_get_next_slave(bond, slave);
+		}
+		read_unlock(&bond->ptrlock);
+
+		bond_info->lp_counter = 0;
+	}
+
+	/* rebalance tx traffic */
+	if (bond_info->tx_rebalance_counter >= BOND_TLB_REBALANCE_TICKS) {
+		read_lock(&bond->ptrlock);
+		slave = bond_get_first_slave(bond);
+		while (slave) {
+			tlb_clear_slave(bond, slave, 1);
+			if (slave == bond->current_slave) {
+				SLAVE_TLB_INFO(slave).load =
+					bond_info->unbalanced_load /
+						BOND_TLB_REBALANCE_INTERVAL;
+				bond_info->unbalanced_load = 0;
+			}
+			slave = bond_get_next_slave(bond, slave);
+		}
+		read_unlock(&bond->ptrlock);
+		bond_info->tx_rebalance_counter = 0;
+	}
+
+	/* handle rlb stuff */
+	if (bond_info->rlb_enabled) {
+		/* the following code changes the promiscuity of the
+		 * the current_slave. It needs to be locked with a
+		 * write lock to protect from other code that also
+		 * sets the promiscuity.
+		 */
+		write_lock(&bond->ptrlock);
+		if (bond_info->primary_is_promisc &&
+		    (++bond_info->rlb_promisc_timeout_counter >=
+			RLB_PROMISC_TIMEOUT)) {
+
+			bond_info->rlb_promisc_timeout_counter = 0;
+
+			/* If the primary was set to promiscuous mode
+			 * because a slave was disabled then
+			 * it can now leave promiscuous mode.
+			 */
+			dev_set_promiscuity(bond->current_slave->dev, -1);
+			bond_info->primary_is_promisc = 0;
+		}
+		write_unlock(&bond->ptrlock);
+
+		if (bond_info->rlb_rebalance == 1) {
+			bond_info->rlb_rebalance = 0;
+			rlb_rebalance(bond);
+		}
+
+		/* check if clients need updating */
+		if (bond_info->rx_ntt) {
+			if (bond_info->rlb_update_delay_counter) {
+				--bond_info->rlb_update_delay_counter;
+			} else {
+				rlb_update_rx_clients(bond);
+				if (bond_info->rlb_update_retry_counter) {
+					--bond_info->rlb_update_retry_counter;
+				} else {
+					bond_info->rx_ntt = 0;
+				}
+			}
+		}
+	}
+
+out:
+	read_unlock(&bond->lock);
+
+	if (bond->device->flags & IFF_UP) {
+		/* re-arm the timer */
+		mod_timer(&(bond_info->alb_timer),
+			jiffies + (HZ/ALB_TIMER_TICKS_PER_SEC));
+	}
+}
+
+/* assumption: called before the slave is attched to the bond
+ * and not locked by the bond lock
+ */
+int
+bond_alb_init_slave(struct bonding *bond, struct slave *slave)
+{
+	int err = 0;
+
+	err = alb_set_mac_addr(slave, slave->perm_hwaddr,
+				bond->alb_info.rlb_enabled);
+	if (err) {
+		return err;
+	}
+
+	/* caller must hold the bond lock for write since the mac addresses
+	 * are compared and may be swapped.
+	 */
+	write_lock_bh(&bond->lock);
+
+	err = alb_handle_addr_collision_on_attach(bond, slave);
+
+	write_unlock_bh(&bond->lock);
+
+	if (err) {
+		return err;
+	}
+
+	tlb_init_slave(slave);
+
+	/* order a rebalance ASAP */
+	bond->alb_info.tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
+
+	if (bond->alb_info.rlb_enabled) {
+		bond->alb_info.rlb_rebalance = 1;
+	}
+
+	return 0;
+}
+
+/* Caller must hold bond lock for write */
+void
+bond_alb_deinit_slave(struct bonding *bond, struct slave *slave)
+{
+	if (bond->slave_cnt > 1) {
+		alb_change_hw_addr_on_detach(bond, slave);
+	}
+
+	tlb_clear_slave(bond, slave, 0);
+
+	if (bond->alb_info.rlb_enabled) {
+		bond->alb_info.next_rx_slave = NULL;
+		rlb_clear_slave(bond, slave);
+	}
+}
+
+/* Caller must hold bond lock for read */
+void
+bond_alb_handle_link_change(struct bonding *bond, struct slave *slave,
+			    char link)
+{
+	struct alb_bond_info *bond_info = &(BOND_ALB_INFO(bond));
+
+	if (link == BOND_LINK_DOWN) {
+		tlb_clear_slave(bond, slave, 0);
+		if (bond->alb_info.rlb_enabled) {
+			rlb_clear_slave(bond, slave);
+		}
+	} else if (link == BOND_LINK_UP) {
+		/* order a rebalance ASAP */
+		bond_info->tx_rebalance_counter = BOND_TLB_REBALANCE_TICKS;
+		if (bond->alb_info.rlb_enabled) {
+			bond->alb_info.rlb_rebalance = 1;
+			/* If the updelay module parameter is smaller than the
+			 * forwarding delay of the switch the rebalance will
+			 * not work because the rebalance arp replies will
+			 * not be forwarded to the clients..
+			 */
+		}
+	}
+}
+
+/**
+ * bond_alb_assign_current_slave - assign new current_slave
+ * @bond: our bonding struct
+ * @new_slave: new slave to assign
+ *
+ * Set the bond->current_slave to @new_slave and handle
+ * mac address swapping and promiscuity changes as needed.
+ *
+ * Caller must hold bond ptrlock for write (or bond lock for write)
+ */
+void
+bond_alb_assign_current_slave(struct bonding *bond, struct slave *new_slave)
+{
+	struct slave *swap_slave = bond->current_slave;
+
+	if (bond->current_slave == new_slave) {
+		return;
+	}
+
+	if (bond->current_slave && bond->alb_info.primary_is_promisc) {
+		dev_set_promiscuity(bond->current_slave->dev, -1);
+		bond->alb_info.primary_is_promisc = 0;
+		bond->alb_info.rlb_promisc_timeout_counter = 0;
+	}
+
+	bond->current_slave = new_slave;
+
+	if (!new_slave || (bond->slave_cnt == 0)) {
+		return;
+	}
+
+	/* set the new current_slave to the bonds mac address
+	 * i.e. swap mac addresses of old current_slave and new current_slave
+	 */
+	if (!swap_slave) {
+		/* find slave that is holding the bond's mac address */
+		swap_slave = bond_get_first_slave(bond);
+		while (swap_slave) {
+			if (!memcmp(swap_slave->dev->dev_addr,
+				bond->device->dev_addr, ETH_ALEN)) {
+				break;
+			}
+			swap_slave = bond_get_next_slave(bond, swap_slave);
+		}
+	}
+
+	/* current_slave must be set before calling alb_swap_mac_addr */
+	if (swap_slave) {
+		/* swap mac address */
+		alb_swap_mac_addr(bond, swap_slave, new_slave);
+	} else {
+		/* set the new_slave to the bond mac address */
+		alb_set_mac_addr(new_slave, bond->device->dev_addr,
+				 bond->alb_info.rlb_enabled);
+		/* fasten bond mac on new current slave */
+		alb_send_learning_packets(new_slave, bond->device->dev_addr);
+	}
+}
+

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)