bonding: add xmit_hash_policy attribute netlink support

Add IFLA_BOND_XMIT_HASH_POLICY to allow get/set of bonding parameter
xmit_hash_policy via netlink.

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

5 files changed, 37 insertions, 7 deletions

diff --git a/drivers/net/bonding/bond_netlink.c b/drivers/net/bonding/bond_netlink.c
index dc465ad3fb7c..67acd21a2170 100644
--- a/drivers/net/bonding/bond_netlink.c
+++ b/drivers/net/bonding/bond_netlink.c
@@ -35,6 +35,7 @@ static const struct nla_policy bond_policy[IFLA_BOND_MAX + 1] = {
         [IFLA_BOND_PRIMARY]             = { .type = NLA_U32 },
         [IFLA_BOND_PRIMARY_RESELECT]    = { .type = NLA_U8 },
         [IFLA_BOND_FAIL_OVER_MAC]       = { .type = NLA_U8 },
+        [IFLA_BOND_XMIT_HASH_POLICY]    = { .type = NLA_U8 },
 };
 
 static int bond_validate(struct nlattr *tb[], struct nlattr *data[])
@@ -186,6 +187,14 @@ static int bond_changelink(struct net_device *bond_dev,
                 if (err)
                         return err;
         }
+        if (data[IFLA_BOND_XMIT_HASH_POLICY]) {
+                int xmit_hash_policy =
+                        nla_get_u8(data[IFLA_BOND_XMIT_HASH_POLICY]);
+
+                err = bond_option_xmit_hash_policy_set(bond, xmit_hash_policy);
+                if (err)
+                        return err;
+        }
         return 0;
 }
 
@@ -217,6 +226,7 @@ static size_t bond_get_size(const struct net_device *bond_dev)
                 nla_total_size(sizeof(u32)) +   /* IFLA_BOND_PRIMARY */
                 nla_total_size(sizeof(u8)) +    /* IFLA_BOND_PRIMARY_RESELECT */
                 nla_total_size(sizeof(u8)) +    /* IFLA_BOND_FAIL_OVER_MAC */
+                nla_total_size(sizeof(u8)) +    /* IFLA_BOND_XMIT_HASH_POLICY */
                 0;
 }
 
@@ -289,6 +299,10 @@ static int bond_fill_info(struct sk_buff *skb,
                        bond->params.fail_over_mac))
                 goto nla_put_failure;
 
+        if (nla_put_u8(skb, IFLA_BOND_XMIT_HASH_POLICY,
+                       bond->params.xmit_policy))
+                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 86f462008932..8510c6df115b 100644
--- a/drivers/net/bonding/bond_options.c
+++ b/drivers/net/bonding/bond_options.c
@@ -551,3 +551,13 @@ int bond_option_fail_over_mac_set(struct bonding *bond, int fail_over_mac)
 
         return 0;
 }
+
+int bond_option_xmit_hash_policy_set(struct bonding *bond, int xmit_hash_policy)
+{
+        bond->params.xmit_policy = xmit_hash_policy;
+        pr_info("%s: setting xmit hash policy to %s (%d).\n",
+                bond->dev->name,
+                xmit_hashtype_tbl[xmit_hash_policy].modename, xmit_hash_policy);
+
+        return 0;
+}
diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c
index c84a90f9a0ac..4c7532289d87 100644
--- a/drivers/net/bonding/bond_sysfs.c
+++ b/drivers/net/bonding/bond_sysfs.c
@@ -318,7 +318,7 @@ static ssize_t bonding_store_xmit_hash(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);
 
         new_value = bond_parse_parm(buf, xmit_hashtype_tbl);
@@ -326,14 +326,17 @@ static ssize_t bonding_store_xmit_hash(struct device *d,
                 pr_err("%s: Ignoring invalid xmit hash policy value %.*s.\n",
                        bond->dev->name,
                        (int)strlen(buf) - 1, buf);
-                ret = -EINVAL;
-        } else {
-                bond->params.xmit_policy = new_value;
-                pr_info("%s: setting xmit hash policy to %s (%d).\n",
-                        bond->dev->name,
-                        xmit_hashtype_tbl[new_value].modename, new_value);
+                return -EINVAL;
         }
 
+        if (!rtnl_trylock())
+                return restart_syscall();
+
+        ret = bond_option_xmit_hash_policy_set(bond, new_value);
+        if (!ret)
+                ret = count;
+
+        rtnl_unlock();
         return ret;
 }
 static DEVICE_ATTR(xmit_hash_policy, S_IRUGO | S_IWUSR,
diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index b69059b361a0..4cb603e9c591 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -458,6 +458,8 @@ int bond_option_primary_set(struct bonding *bond, const char *primary);
 int bond_option_primary_reselect_set(struct bonding *bond,
                                      int primary_reselect);
 int bond_option_fail_over_mac_set(struct bonding *bond, int fail_over_mac);
+int bond_option_xmit_hash_policy_set(struct bonding *bond,
+                                     int xmit_hash_policy);
 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 fd181abd19b9..1a5d394894ea 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -342,6 +342,7 @@ enum {
         IFLA_BOND_PRIMARY,
         IFLA_BOND_PRIMARY_RESELECT,
         IFLA_BOND_FAIL_OVER_MAC,
+        IFLA_BOND_XMIT_HASH_POLICY,
         __IFLA_BOND_MAX,
 };