[net-next v2 07/11] net: bridge: mcast: prepare add-router function for mcast router split

Linus Lüssing
2021-05-09T19:45:55Z

In preparation for the upcoming split of multicast router state into
their IPv4 and IPv6 variants move the protocol specific router list
access to an ip4 wrapper function.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
---
net/bridge/br_multicast.c | 59 +++++++++++++++++++++++++++------------
1 file changed, 41 insertions(+), 18 deletions(-)

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 6c844b2..839d21b 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -51,8 +51,8 @@ static const struct rhashtable_params br_sg_port_rht_params = {

static void br_multicast_start_querier(struct net_bridge *br,
struct bridge_mcast_own_query *query);
-static void br_multicast_add_router(struct net_bridge *br,
- struct net_bridge_port *port);
+static void br_ip4_multicast_add_router(struct net_bridge *br,
+ struct net_bridge_port *port);
static void br_ip4_multicast_leave_group(struct net_bridge *br,
struct net_bridge_port *port,
__be32 group,
@@ -1689,7 +1689,7 @@ static void __br_multicast_enable_port(struct net_bridge_port *port)
#endif
if (port->multicast_router == MDB_RTR_TYPE_PERM &&
hlist_unhashed(&port->ip4_rlist))
- br_multicast_add_router(br, port);
+ br_ip4_multicast_add_router(br, port);
}

void br_multicast_enable_port(struct net_bridge_port *port)
@@ -2659,28 +2659,51 @@ static void br_port_mc_router_state_change(struct net_bridge_port *p,
* and locked by br->multicast_lock and RCU
*/
static void br_multicast_add_router(struct net_bridge *br,
- struct net_bridge_port *port)
+ struct net_bridge_port *port,
+ struct hlist_node *slot,
+ struct hlist_node *rlist,
+ struct hlist_head *mc_router_list)
{
- struct net_bridge_port *p;
- struct hlist_node *slot = NULL;
-
- if (!hlist_unhashed(&port->ip4_rlist))
+ if (!hlist_unhashed(rlist))
return;

- hlist_for_each_entry(p, &br->ip4_mc_router_list, ip4_rlist) {
- if ((unsigned long) port >= (unsigned long) p)
- break;
- slot = &p->ip4_rlist;
- }
-
if (slot)
- hlist_add_behind_rcu(&port->ip4_rlist, slot);
+ hlist_add_behind_rcu(rlist, slot);
else
- hlist_add_head_rcu(&port->ip4_rlist, &br->ip4_mc_router_list);
+ hlist_add_head_rcu(rlist, mc_router_list);
+
br_rtr_notify(br->dev, port, RTM_NEWMDB);
br_port_mc_router_state_change(port, true);
}

+struct hlist_node *
+br_ip4_multicast_get_rport_slot(struct net_bridge *br, struct net_bridge_port *port)
+{
+ struct hlist_node *slot = NULL;
+ struct net_bridge_port *p;
+
+ hlist_for_each_entry(p, &br->ip4_mc_router_list, ip4_rlist) {
+ if ((unsigned long)port >= (unsigned long)p)
+ break;
+ slot = &p->ip4_rlist;
+ }
+
+ return slot;
+}
+
+/* Add port to router_list
+ * list is maintained ordered by pointer value
+ * and locked by br->multicast_lock and RCU
+ */
+static void br_ip4_multicast_add_router(struct net_bridge *br,
+ struct net_bridge_port *port)
+{
+ struct hlist_node *slot = br_ip4_multicast_get_rport_slot(br, port);
+
+ br_multicast_add_router(br, port, slot, &port->ip4_rlist,
+ &br->ip4_mc_router_list);
+}
+
static void br_multicast_mark_router(struct net_bridge *br,
struct net_bridge_port *port)
{
@@ -2700,7 +2723,7 @@ static void br_multicast_mark_router(struct net_bridge *br,
port->multicast_router == MDB_RTR_TYPE_PERM)
return;

- br_multicast_add_router(br, port);
+ br_ip4_multicast_add_router(br, port);

mod_timer(&port->ip4_mc_router_timer,
now + br->multicast_querier_interval);
@@ -3526,7 +3549,7 @@ int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
case MDB_RTR_TYPE_PERM:
p->multicast_router = MDB_RTR_TYPE_PERM;
del_timer(&p->ip4_mc_router_timer);
- br_multicast_add_router(br, p);
+ br_ip4_multicast_add_router(br, p);
break;
case MDB_RTR_TYPE_TEMP:
p->multicast_router = MDB_RTR_TYPE_TEMP;
--
2.31.0