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

From: Horatiu Vultur
Date: Tue Jun 30 2020 - 09:46:03 EST


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