bonding: add min links parameter to 802.3ad

This adds support for a configuring the minimum number of links that
must be active before asserting carrier. It is similar to the Cisco
EtherChannel min-links feature. This allows setting the minimum number
of member ports that must be up (link-up state) before marking the
bond device as up (carrier on). This is useful for situations where
higher level services such as clustering want to ensure a minimum
number of low bandwidth links are active before switchover.

See:
   http://bugzilla.vyatta.com/show_bug.cgi?id=7196

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index 77da2e8..a047eb9 100644 (file)
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c
@@ -2342,8 +2342,17 @@ void bond_3ad_handle_link_change(struct slave *slave, char link)
  */
 int bond_3ad_set_carrier(struct bonding *bond)
 {
-       if (__get_active_agg(&(SLAVE_AD_INFO(bond->first_slave).aggregator))) {
-               if (!netif_carrier_ok(bond->dev)) {
+       struct aggregator *active;
+
+       active = __get_active_agg(&(SLAVE_AD_INFO(bond->first_slave).aggregator));
+       if (active) {
+               /* are enough slaves available to consider link up? */
+               if (active->num_of_ports < bond->params.min_links) {
+                       if (netif_carrier_ok(bond->dev)) {
+                               netif_carrier_off(bond->dev);
+                               return 1;
+                       }
+               } else if (!netif_carrier_ok(bond->dev)) {
                        netif_carrier_on(bond->dev);
                        return 1;
                }

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index ebb1d21..61265f7 100644 (file)
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -98,6 +98,7 @@ static char *mode;
 static char *primary;
 static char *primary_reselect;
 static char *lacp_rate;
+static int min_links;
 static char *ad_select;
 static char *xmit_hash_policy;
 static int arp_interval = BOND_LINK_ARP_INTERV;
@@ -150,6 +151,9 @@ module_param(ad_select, charp, 0);
 MODULE_PARM_DESC(ad_select, "803.ad aggregation selection logic; "
                            "0 for stable (default), 1 for bandwidth, "
                            "2 for count");
+module_param(min_links, int, 0);
+MODULE_PARM_DESC(min_links, "Minimum number of available links before turning on carrier");
+
 module_param(xmit_hash_policy, charp, 0);
 MODULE_PARM_DESC(xmit_hash_policy, "balance-xor and 802.3ad hashing method; "
                                   "0 for layer 2 (default), 1 for layer 3+4, "
@@ -4798,6 +4802,7 @@ static int bond_check_params(struct bond_params *params)
        params->tx_queues = tx_queues;
        params->all_slaves_active = all_slaves_active;
        params->resend_igmp = resend_igmp;
+       params->min_links = min_links;
 
        if (primary) {
                strncpy(params->primary, primary, IFNAMSIZ);

diff --git a/drivers/net/bonding/bond_procfs.c b/drivers/net/bonding/bond_procfs.c
index c97307d..95de93b 100644 (file)
--- a/drivers/net/bonding/bond_procfs.c
+++ b/drivers/net/bonding/bond_procfs.c
@@ -125,6 +125,7 @@ static void bond_info_show_master(struct seq_file *seq)
                seq_puts(seq, "\n802.3ad info\n");
                seq_printf(seq, "LACP rate: %s\n",
                           (bond->params.lacp_fast) ? "fast" : "slow");
+               seq_printf(seq, "Min links: %d\n", bond->params.min_links);
                seq_printf(seq, "Aggregator selection policy (ad_select): %s\n",
                           ad_select_tbl[bond->params.ad_select].modename);
 

diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c
index 03d1196..b60835f 100644 (file)
--- a/drivers/net/bonding/bond_sysfs.c
+++ b/drivers/net/bonding/bond_sysfs.c
@@ -819,6 +819,38 @@ out:
 static DEVICE_ATTR(lacp_rate, S_IRUGO | S_IWUSR,
                   bonding_show_lacp, bonding_store_lacp);
 
+static ssize_t bonding_show_min_links(struct device *d,
+                                     struct device_attribute *attr,
+                                     char *buf)
+{
+       struct bonding *bond = to_bond(d);
+
+       return sprintf(buf, "%d\n", bond->params.min_links);
+}
+
+static ssize_t bonding_store_min_links(struct device *d,
+                                      struct device_attribute *attr,
+                                      const char *buf, size_t count)
+{
+       struct bonding *bond = to_bond(d);
+       int ret;
+       unsigned int new_value;
+
+       ret = kstrtouint(buf, 0, &new_value);
+       if (ret < 0) {
+               pr_err("%s: Ignoring invalid min links value %s.\n",
+                      bond->dev->name, buf);
+               return ret;
+       }
+
+       pr_info("%s: Setting min links value to %u\n",
+               bond->dev->name, new_value);
+       bond->params.min_links = new_value;
+       return count;
+}
+static DEVICE_ATTR(min_links, S_IRUGO | S_IWUSR,
+                  bonding_show_min_links, bonding_store_min_links);
+
 static ssize_t bonding_show_ad_select(struct device *d,
                                      struct device_attribute *attr,
                                      char *buf)
@@ -1601,6 +1633,7 @@ static struct attribute *per_bond_attrs[] = {
        &dev_attr_queue_id.attr,
        &dev_attr_all_slaves_active.attr,
        &dev_attr_resend_igmp.attr,
+       &dev_attr_min_links.attr,
        NULL,
 };
 

diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index 382903f..2936171 100644 (file)
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -147,6 +147,7 @@ struct bond_params {
        int updelay;
        int downdelay;
        int lacp_fast;
+       unsigned int min_links;
        int ad_select;
        char primary[IFNAMSIZ];
        int primary_reselect;