net/bonding: Optionally allow ethernet slaves to keep own MAC

	Update the "don't change MAC of slaves" functionality added in
previous changes to be a generic option, rather than something tied to
IB devices, as it's occasionally useful for regular ethernet devices as
well.

	Adds "fail_over_mac" option (which is automatically enabled for IB
slaves), applicable only to active-backup mode.

	Includes documentation update.

	Updates bonding driver version to 3.2.0.

Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 36 insertions, 21 deletions

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 0e198dd87c2..db80f243dd3 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -98,6 +98,7 @@ static char *xmit_hash_policy = NULL;
 static int arp_interval = BOND_LINK_ARP_INTERV;
 static char *arp_ip_target[BOND_MAX_ARP_TARGETS] = { NULL, };
 static char *arp_validate = NULL;
+static int fail_over_mac = 0;
 struct bond_params bonding_defaults;
 
 module_param(max_bonds, int, 0);
@@ -131,6 +132,8 @@ module_param_array(arp_ip_target, charp, NULL, 0);
 MODULE_PARM_DESC(arp_ip_target, "arp targets in n.n.n.n form");
 module_param(arp_validate, charp, 0);
 MODULE_PARM_DESC(arp_validate, "validate src/dst of ARP probes: none (default), active, backup or all");
+module_param(fail_over_mac, int, 0);
+MODULE_PARM_DESC(fail_over_mac, "For active-backup, do not set all slaves to the same MAC.  0 of off (default), 1 for on.");
 
 /*----------------------------- Global variables ----------------------------*/
 
@@ -1100,7 +1103,7 @@ void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
                 /* when bonding does not set the slave MAC address, the bond MAC
                  * address is the one of the active slave.
                  */
-                if (new_active && !bond->do_set_mac_addr)
+                if (new_active && bond->params.fail_over_mac)
                         memcpy(bond->dev->dev_addr,  new_active->dev->dev_addr,
                                 new_active->dev->addr_len);
                 if (bond->curr_active_slave &&
@@ -1367,16 +1370,16 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
         if (slave_dev->set_mac_address == NULL) {
                 if (bond->slave_cnt == 0) {
                         printk(KERN_WARNING DRV_NAME
-                                ": %s: Warning: The first slave device you "
-                                "specified does not support setting the MAC "
-                                "address. This bond MAC address would be that "
-                                "of the active slave.\n", bond_dev->name);
-                        bond->do_set_mac_addr = 0;
-                } else if (bond->do_set_mac_addr) {
+                               ": %s: Warning: The first slave device "
+                               "specified does not support setting the MAC "
+                               "address. Enabling the fail_over_mac option.",
+                               bond_dev->name);
+                        bond->params.fail_over_mac = 1;
+                } else if (!bond->params.fail_over_mac) {
                         printk(KERN_ERR DRV_NAME
-                                ": %s: Error: The slave device you specified "
-                                "does not support setting the MAC addres,."
-                                "but this bond uses this practice. \n"
+                                ": %s: Error: The slave device specified "
+                                "does not support setting the MAC address, "
+                                "but fail_over_mac is not enabled.\n"
                                 , bond_dev->name);
                         res = -EOPNOTSUPP;
                         goto err_undo_flags;
@@ -1401,7 +1404,7 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
          */
         memcpy(new_slave->perm_hwaddr, slave_dev->dev_addr, ETH_ALEN);
 
-        if (bond->do_set_mac_addr) {
+        if (!bond->params.fail_over_mac) {
                 /*
                  * Set slave to master's mac address.  The application already
                  * set the master's mac address to that of the first slave
@@ -1637,7 +1640,7 @@ err_close:
         dev_close(slave_dev);
 
 err_restore_mac:
-        if (bond->do_set_mac_addr) {
+        if (!bond->params.fail_over_mac) {
                 memcpy(addr.sa_data, new_slave->perm_hwaddr, ETH_ALEN);
                 addr.sa_family = slave_dev->type;
                 dev_set_mac_address(slave_dev, &addr);
@@ -1814,7 +1817,7 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
         /* close slave before restoring its mac address */
         dev_close(slave_dev);
 
-        if (bond->do_set_mac_addr) {
+        if (!bond->params.fail_over_mac) {
                 /* restore original ("permanent") mac address */
                 memcpy(addr.sa_data, slave->perm_hwaddr, ETH_ALEN);
                 addr.sa_family = slave_dev->type;
@@ -1935,7 +1938,7 @@ static int bond_release_all(struct net_device *bond_dev)
                 /* close slave before restoring its mac address */
                 dev_close(slave_dev);
 
-                if (bond->do_set_mac_addr) {
+                if (!bond->params.fail_over_mac) {
                         /* restore original ("permanent") mac address*/
                         memcpy(addr.sa_data, slave->perm_hwaddr, ETH_ALEN);
                         addr.sa_family = slave_dev->type;
@@ -3060,9 +3063,15 @@ static void bond_info_show_master(struct seq_file *seq)
         curr = bond->curr_active_slave;
         read_unlock(&bond->curr_slave_lock);
 
-        seq_printf(seq, "Bonding Mode: %s\n",
+        seq_printf(seq, "Bonding Mode: %s",
                    bond_mode_name(bond->params.mode));
 
+        if (bond->params.mode == BOND_MODE_ACTIVEBACKUP &&
+            bond->params.fail_over_mac)
+                seq_printf(seq, " (fail_over_mac)");
+
+        seq_printf(seq, "\n");
+
         if (bond->params.mode == BOND_MODE_XOR ||
                 bond->params.mode == BOND_MODE_8023AD) {
                 seq_printf(seq, "Transmit Hash Policy: %s (%d)\n",
@@ -3994,8 +4003,12 @@ static int bond_set_mac_address(struct net_device *bond_dev, void *addr)
 
         dprintk("bond=%p, name=%s\n", bond, (bond_dev ? bond_dev->name : "None"));
 
-        if (!bond->do_set_mac_addr)
-                return -EOPNOTSUPP;
+        /*
+         * If fail_over_mac is enabled, do nothing and return success.
+         * Returning an error causes ifenslave to fail.
+         */
+        if (bond->params.fail_over_mac)
+                return 0;
 
         if (!is_valid_ether_addr(sa->sa_data)) {
                 return -EADDRNOTAVAIL;
@@ -4384,10 +4397,6 @@ static int bond_init(struct net_device *bond_dev, struct bond_params *params)
 #ifdef CONFIG_PROC_FS
         bond_create_proc_entry(bond);
 #endif
-
-        /* set do_set_mac_addr to true on startup */
-        bond->do_set_mac_addr = 1;
-
         list_add_tail(&bond->bond_list, &bond_dev_list);
 
         return 0;
@@ -4721,6 +4730,11 @@ static int bond_check_params(struct bond_params *params)
                 primary = NULL;
         }
 
+        if (fail_over_mac && (bond_mode != BOND_MODE_ACTIVEBACKUP))
+                printk(KERN_WARNING DRV_NAME
+                       ": Warning: fail_over_mac only affects "
+                       "active-backup mode.\n");
+
         /* fill params struct with the proper values */
         params->mode = bond_mode;
         params->xmit_policy = xmit_hashtype;
@@ -4732,6 +4746,7 @@ static int bond_check_params(struct bond_params *params)
         params->use_carrier = use_carrier;
         params->lacp_fast = lacp_fast;
         params->primary[0] = 0;
+        params->fail_over_mac = fail_over_mac;
 
         if (primary) {
                 strncpy(params->primary, primary, IFNAMSIZ);