[PATCH net-next 3/3] bridge: Extend br_fill_ifinfo to return MPR status

[Horatiu Vultur]

This patch extends the function br_fill_ifinfo to return also the MRP
status for each instance on a bridge. It also adds a new filter
RTEXT_FILTER_MRP to return the MRP status only when this is set, not to
interfer with the vlans. The MRP status is return only on the bridge
interfaces.

Signed-off-by: Horatiu Vultur <horatiu.vultur@xxxxxxxxxxxxx>
---
 include/uapi/linux/rtnetlink.h |  1 +
 net/bridge/br_netlink.c        | 29 ++++++++++++++++++++++++++++-
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/rtnetlink.h b/include/uapi/linux/rtnetlink.h
index 879e64950a0a2..9b814c92de123 100644
--- a/include/uapi/linux/rtnetlink.h
+++ b/include/uapi/linux/rtnetlink.h
@@ -778,6 +778,7 @@ enum {
 #define RTEXT_FILTER_BRVLAN	(1 << 1)
 #define RTEXT_FILTER_BRVLAN_COMPRESSED	(1 << 2)
 #define	RTEXT_FILTER_SKIP_STATS	(1 << 3)
+#define RTEXT_FILTER_MRP	(1 << 4)
 
 /* End of information exported to user level */
 
diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 240e260e3461c..6ecb7c7453dcb 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -453,6 +453,32 @@ static int br_fill_ifinfo(struct sk_buff *skb,
 		rcu_read_unlock();
 		if (err)
 			goto nla_put_failure;
+
+		nla_nest_end(skb, af);
+	}
+
+	if (filter_mask & RTEXT_FILTER_MRP) {
+		struct nlattr *af;
+		int err;
+
+		/* RCU needed because of the VLAN locking rules (rcu || rtnl) */
+		rcu_read_lock();
+		if (!br_mrp_enabled(br) || port) {
+			rcu_read_unlock();
+			goto done;
+		}
+		af = nla_nest_start_noflag(skb, IFLA_AF_SPEC);
+		if (!af) {
+			rcu_read_unlock();
+			goto nla_put_failure;
+		}
+
+		err = br_mrp_fill_info(skb, br);
+
+		rcu_read_unlock();
+		if (err)
+			goto nla_put_failure;
+
 		nla_nest_end(skb, af);
 	}
 
@@ -516,7 +542,8 @@ int br_getlink(struct sk_buff *skb, u32 pid, u32 seq,
 	struct net_bridge_port *port = br_port_get_rtnl(dev);
 
 	if (!port && !(filter_mask & RTEXT_FILTER_BRVLAN) &&
-	    !(filter_mask & RTEXT_FILTER_BRVLAN_COMPRESSED))
+	    !(filter_mask & RTEXT_FILTER_BRVLAN_COMPRESSED) &&
+	    !(filter_mask & RTEXT_FILTER_MRP))
 		return 0;
 
 	return br_fill_ifinfo(skb, port, pid, seq, RTM_NEWLINK, nlflags,
-- 
2.27.0