bonding: add use_carrier netlink support

Add IFLA_BOND_USE_CARRIER to allow get/set of bonding parameter
use_carrier via netlink.

Signed-off-by: Scott Feldman <sfeldma@cumulusnetworks.com>
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 39 insertions, 13 deletions

diff --git a/drivers/net/bonding/bond_netlink.c b/drivers/net/bonding/bond_netlink.c
index a0a2e8c32fe5..7edf6399cea2 100644
--- a/drivers/net/bonding/bond_netlink.c
+++ b/drivers/net/bonding/bond_netlink.c
@@ -27,6 +27,7 @@ static const struct nla_policy bond_policy[IFLA_BOND_MAX + 1] = {
         [IFLA_BOND_MIIMON]              = { .type = NLA_U32 },
         [IFLA_BOND_UPDELAY]             = { .type = NLA_U32 },
         [IFLA_BOND_DOWNDELAY]           = { .type = NLA_U32 },
+        [IFLA_BOND_USE_CARRIER]         = { .type = NLA_U8 },
 };
 
 static int bond_validate(struct nlattr *tb[], struct nlattr *data[])
@@ -93,6 +94,13 @@ static int bond_changelink(struct net_device *bond_dev,
                 if (err)
                         return err;
         }
+        if (data[IFLA_BOND_USE_CARRIER]) {
+                int use_carrier = nla_get_u8(data[IFLA_BOND_USE_CARRIER]);
+
+                err = bond_option_use_carrier_set(bond, use_carrier);
+                if (err)
+                        return err;
+        }
         return 0;
 }
 
@@ -115,6 +123,7 @@ static size_t bond_get_size(const struct net_device *bond_dev)
                 nla_total_size(sizeof(u32)) +   /* IFLA_BOND_MIIMON */
                 nla_total_size(sizeof(u32)) +   /* IFLA_BOND_UPDELAY */
                 nla_total_size(sizeof(u32)) +   /* IFLA_BOND_DOWNDELAY */
+                nla_total_size(sizeof(u8)) +    /* IFLA_BOND_USE_CARRIER */
                 0;
 }
 
@@ -142,6 +151,9 @@ static int bond_fill_info(struct sk_buff *skb,
                         bond->params.downdelay * bond->params.miimon))
                 goto nla_put_failure;
 
+        if (nla_put_u8(skb, IFLA_BOND_USE_CARRIER, bond->params.use_carrier))
+                goto nla_put_failure;
+
         return 0;
 
 nla_put_failure:
diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c
index 2914d649ee34..6fc7bbf0b85f 100644
--- a/drivers/net/bonding/bond_options.c
+++ b/drivers/net/bonding/bond_options.c
@@ -245,3 +245,17 @@ int bond_option_downdelay_set(struct bonding *bond, int downdelay)
 
         return 0;
 }
+
+int bond_option_use_carrier_set(struct bonding *bond, int use_carrier)
+{
+        if ((use_carrier == 0) || (use_carrier == 1)) {
+                bond->params.use_carrier = use_carrier;
+                pr_info("%s: Setting use_carrier to %d.\n",
+                        bond->dev->name, use_carrier);
+        } else {
+                pr_info("%s: Ignoring invalid use_carrier value %d.\n",
+                        bond->dev->name, use_carrier);
+        }
+
+        return 0;
+}
diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c
index bec20bc08d31..114760af9a6d 100644
--- a/drivers/net/bonding/bond_sysfs.c
+++ b/drivers/net/bonding/bond_sysfs.c
@@ -1097,25 +1097,23 @@ static ssize_t bonding_store_carrier(struct device *d,
                                      struct device_attribute *attr,
                                      const char *buf, size_t count)
 {
-        int new_value, ret = count;
+        int new_value, ret;
         struct bonding *bond = to_bond(d);
 
-
         if (sscanf(buf, "%d", &new_value) != 1) {
                 pr_err("%s: no use_carrier value specified.\n",
                        bond->dev->name);
-                ret = -EINVAL;
-                goto out;
-        }
-        if ((new_value == 0) || (new_value == 1)) {
-                bond->params.use_carrier = new_value;
-                pr_info("%s: Setting use_carrier to %d.\n",
-                        bond->dev->name, new_value);
-        } else {
-                pr_info("%s: Ignoring invalid use_carrier value %d.\n",
-                        bond->dev->name, new_value);
+                return -EINVAL;
         }
-out:
+
+        if (!rtnl_trylock())
+                return restart_syscall();
+
+        ret = bond_option_use_carrier_set(bond, new_value);
+        if (!ret)
+                ret = count;
+
+        rtnl_unlock();
         return ret;
 }
 static DEVICE_ATTR(use_carrier, S_IRUGO | S_IWUSR,
diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index f5749b18d168..df159da8db30 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -442,6 +442,7 @@ int bond_option_active_slave_set(struct bonding *bond, struct net_device *slave_
 int bond_option_miimon_set(struct bonding *bond, int miimon);
 int bond_option_updelay_set(struct bonding *bond, int updelay);
 int bond_option_downdelay_set(struct bonding *bond, int downdelay);
+int bond_option_use_carrier_set(struct bonding *bond, int use_carrier);
 struct net_device *bond_option_active_slave_get_rcu(struct bonding *bond);
 struct net_device *bond_option_active_slave_get(struct bonding *bond);
 
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index f95506777710..77c41bda36a4 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -334,6 +334,7 @@ enum {
         IFLA_BOND_MIIMON,
         IFLA_BOND_UPDELAY,
         IFLA_BOND_DOWNDELAY,
+        IFLA_BOND_USE_CARRIER,
         __IFLA_BOND_MAX,
 };