bridge: implement rtnl_link_ops->get_size and rtnl_link_ops->fill_info

Allow rtnetlink users to get bridge master info in IFLA_INFO_DATA attr
This initial part implements forward_delay, hello_time, max_age options.

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

2 files changed, 37 insertions, 0 deletions

diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index ff957604a721..c80f95f6ee78 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -215,6 +215,18 @@ enum in6_addr_gen_mode {
         IN6_ADDR_GEN_MODE_NONE,
 };
 
+/* Bridge section */
+
+enum {
+        IFLA_BR_UNSPEC,
+        IFLA_BR_FORWARD_DELAY,
+        IFLA_BR_HELLO_TIME,
+        IFLA_BR_MAX_AGE,
+        __IFLA_BR_MAX,
+};
+
+#define IFLA_BR_MAX     (__IFLA_BR_MAX - 1)
+
 enum {
         BRIDGE_MODE_UNSPEC,
         BRIDGE_MODE_HAIRPIN,
diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 05aeea1222a7..bcac09fe2ac8 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -484,6 +484,29 @@ static size_t br_port_get_slave_size(const struct net_device *brdev,
         return br_port_info_size();
 }
 
+static size_t br_get_size(const struct net_device *brdev)
+{
+        return nla_total_size(sizeof(u32)) +    /* IFLA_BR_FORWARD_DELAY  */
+               nla_total_size(sizeof(u32)) +    /* IFLA_BR_HELLO_TIME */
+               nla_total_size(sizeof(u32)) +    /* IFLA_BR_MAX_AGE */
+               0;
+}
+
+static int br_fill_info(struct sk_buff *skb, const struct net_device *brdev)
+{
+        struct net_bridge *br = netdev_priv(brdev);
+        u32 forward_delay = jiffies_to_clock_t(br->forward_delay);
+        u32 hello_time = jiffies_to_clock_t(br->hello_time);
+        u32 age_time = jiffies_to_clock_t(br->max_age);
+
+        if (nla_put_u32(skb, IFLA_BR_FORWARD_DELAY, forward_delay) ||
+            nla_put_u32(skb, IFLA_BR_HELLO_TIME, hello_time) ||
+            nla_put_u32(skb, IFLA_BR_MAX_AGE, age_time))
+                return -EMSGSIZE;
+
+        return 0;
+}
+
 static size_t br_get_link_af_size(const struct net_device *dev)
 {
         struct net_port_vlans *pv;
@@ -514,6 +537,8 @@ struct rtnl_link_ops br_link_ops __read_mostly = {
         .validate               = br_validate,
         .newlink                = br_dev_newlink,
         .dellink                = br_dev_delete,
+        .get_size               = br_get_size,
+        .fill_info              = br_fill_info,
 
         .slave_maxtype          = IFLA_BRPORT_MAX,
         .slave_policy           = br_port_policy,