Nikolay Aleksandrov
2020-Sep-05 08:24 UTC
[Bridge] [PATCH net-next v3 06/15] net: bridge: mcast: add support for group query retransmit
We need to be able to retransmit group-specific and group-and-source
specific queries. The new timer takes care of those.
v3: add IPv6 support
Signed-off-by: Nikolay Aleksandrov <nikolay at cumulusnetworks.com>
---
net/bridge/br_multicast.c | 73 +++++++++++++++++++++++++++++++++------
net/bridge/br_private.h | 8 +++++
2 files changed, 71 insertions(+), 10 deletions(-)
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 72b32398e279..2f77be9fce9b 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -50,6 +50,7 @@ static void br_ip4_multicast_leave_group(struct net_bridge
*br,
__be32 group,
__u16 vid,
const unsigned char *src);
+static void br_multicast_port_group_rexmit(struct timer_list *t);
static void __del_port_router(struct net_bridge_port *p);
#if IS_ENABLED(CONFIG_IPV6)
@@ -184,6 +185,7 @@ void br_multicast_del_pg(struct net_bridge_mdb_entry *mp,
rcu_assign_pointer(*pp, pg->next);
hlist_del_init(&pg->mglist);
del_timer(&pg->timer);
+ del_timer(&pg->rexmit_timer);
hlist_for_each_entry_safe(ent, tmp, &pg->src_list, node)
br_multicast_del_group_src(ent);
br_mdb_notify(br->dev, pg->port, &pg->addr, RTM_DELMDB,
pg->flags);
@@ -237,7 +239,8 @@ static struct sk_buff *br_ip4_multicast_alloc_query(struct
net_bridge *br,
struct net_bridge_port_group *pg,
__be32 ip_dst, __be32 group,
bool with_srcs, bool over_lmqt,
- u8 sflag, u8 *igmp_type)
+ u8 sflag, u8 *igmp_type,
+ bool *need_rexmit)
{
struct net_bridge_port *p = pg ? pg->port : NULL;
struct net_bridge_group_src *ent;
@@ -352,6 +355,8 @@ static struct sk_buff *br_ip4_multicast_alloc_query(struct
net_bridge *br,
ent->src_query_rexmit_cnt > 0) {
ihv3->srcs[lmqt_srcs++] = ent->addr.u.ip4;
ent->src_query_rexmit_cnt--;
+ if (need_rexmit && ent->src_query_rexmit_cnt)
+ *need_rexmit = true;
}
}
if (WARN_ON(lmqt_srcs != ntohs(ihv3->nsrcs))) {
@@ -380,7 +385,8 @@ static struct sk_buff *br_ip6_multicast_alloc_query(struct
net_bridge *br,
const struct in6_addr *ip6_dst,
const struct in6_addr *group,
bool with_srcs, bool over_llqt,
- u8 sflag, u8 *igmp_type)
+ u8 sflag, u8 *igmp_type,
+ bool *need_rexmit)
{
struct net_bridge_port *p = pg ? pg->port : NULL;
struct net_bridge_group_src *ent;
@@ -510,6 +516,8 @@ static struct sk_buff *br_ip6_multicast_alloc_query(struct
net_bridge *br,
ent->src_query_rexmit_cnt > 0) {
mld2q->mld2q_srcs[llqt_srcs++] = ent->addr.u.ip6;
ent->src_query_rexmit_cnt--;
+ if (need_rexmit && ent->src_query_rexmit_cnt)
+ *need_rexmit = true;
}
}
if (WARN_ON(llqt_srcs != ntohs(mld2q->mld2q_nsrcs))) {
@@ -540,7 +548,8 @@ static struct sk_buff *br_multicast_alloc_query(struct
net_bridge *br,
struct br_ip *ip_dst,
struct br_ip *group,
bool with_srcs, bool over_lmqt,
- u8 sflag, u8 *igmp_type)
+ u8 sflag, u8 *igmp_type,
+ bool *need_rexmit)
{
__be32 ip4_dst;
@@ -550,7 +559,8 @@ static struct sk_buff *br_multicast_alloc_query(struct
net_bridge *br,
return br_ip4_multicast_alloc_query(br, pg,
ip4_dst, group->u.ip4,
with_srcs, over_lmqt,
- sflag, igmp_type);
+ sflag, igmp_type,
+ need_rexmit);
#if IS_ENABLED(CONFIG_IPV6)
case htons(ETH_P_IPV6): {
struct in6_addr ip6_dst;
@@ -564,7 +574,8 @@ static struct sk_buff *br_multicast_alloc_query(struct
net_bridge *br,
return br_ip6_multicast_alloc_query(br, pg,
&ip6_dst, &group->u.ip6,
with_srcs, over_lmqt,
- sflag, igmp_type);
+ sflag, igmp_type,
+ need_rexmit);
}
#endif
}
@@ -708,8 +719,9 @@ struct net_bridge_port_group *br_multicast_new_port_group(
p->filter_mode = filter_mode;
INIT_HLIST_HEAD(&p->src_list);
rcu_assign_pointer(p->next, next);
- hlist_add_head(&p->mglist, &port->mglist);
timer_setup(&p->timer, br_multicast_port_group_expired, 0);
+ timer_setup(&p->rexmit_timer, br_multicast_port_group_rexmit, 0);
+ hlist_add_head(&p->mglist, &port->mglist);
if (src)
memcpy(p->eth_addr, src, ETH_ALEN);
@@ -943,7 +955,8 @@ static void __br_multicast_send_query(struct net_bridge *br,
struct br_ip *ip_dst,
struct br_ip *group,
bool with_srcs,
- u8 sflag)
+ u8 sflag,
+ bool *need_rexmit)
{
bool over_lmqt = !!sflag;
struct sk_buff *skb;
@@ -951,7 +964,8 @@ static void __br_multicast_send_query(struct net_bridge *br,
again_under_lmqt:
skb = br_multicast_alloc_query(br, pg, ip_dst, group, with_srcs,
- over_lmqt, sflag, &igmp_type);
+ over_lmqt, sflag, &igmp_type,
+ need_rexmit);
if (!skb)
return;
@@ -1004,7 +1018,8 @@ static void br_multicast_send_query(struct net_bridge *br,
if (!other_query || timer_pending(&other_query->timer))
return;
- __br_multicast_send_query(br, port, NULL, NULL, &br_group, false, 0);
+ __br_multicast_send_query(br, port, NULL, NULL, &br_group, false, 0,
+ NULL);
time = jiffies;
time += own_query->startup_sent < br->multicast_startup_query_count ?
@@ -1049,6 +1064,44 @@ static void br_ip6_multicast_port_query_expired(struct
timer_list *t)
}
#endif
+static void br_multicast_port_group_rexmit(struct timer_list *t)
+{
+ struct net_bridge_port_group *pg = from_timer(pg, t, rexmit_timer);
+ struct bridge_mcast_other_query *other_query = NULL;
+ struct net_bridge *br = pg->port->br;
+ bool need_rexmit = false;
+
+ spin_lock(&br->multicast_lock);
+ if (!netif_running(br->dev) || hlist_unhashed(&pg->mglist) ||
+ !br_opt_get(br, BROPT_MULTICAST_ENABLED) ||
+ !br_opt_get(br, BROPT_MULTICAST_QUERIER))
+ goto out;
+
+ if (pg->addr.proto == htons(ETH_P_IP))
+ other_query = &br->ip4_other_query;
+#if IS_ENABLED(CONFIG_IPV6)
+ else
+ other_query = &br->ip6_other_query;
+#endif
+
+ if (!other_query || timer_pending(&other_query->timer))
+ goto out;
+
+ if (pg->grp_query_rexmit_cnt) {
+ pg->grp_query_rexmit_cnt--;
+ __br_multicast_send_query(br, pg->port, pg, &pg->addr,
+ &pg->addr, false, 1, NULL);
+ }
+ __br_multicast_send_query(br, pg->port, pg, &pg->addr,
+ &pg->addr, true, 0, &need_rexmit);
+
+ if (pg->grp_query_rexmit_cnt || need_rexmit)
+ mod_timer(&pg->rexmit_timer, jiffies +
+ br->multicast_last_member_interval);
+out:
+ spin_unlock(&br->multicast_lock);
+}
+
static void br_mc_disabled_update(struct net_device *dev, bool value)
{
struct switchdev_attr attr = {
@@ -1657,7 +1710,7 @@ br_multicast_leave_group(struct net_bridge *br,
if (br_opt_get(br, BROPT_MULTICAST_QUERIER)) {
__br_multicast_send_query(br, port, NULL, NULL, &mp->addr,
- false, 0);
+ false, 0, NULL);
time = jiffies + br->multicast_last_member_count *
br->multicast_last_member_interval;
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index e0632721b1ef..da8df273dd4a 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -240,10 +240,12 @@ struct net_bridge_port_group {
unsigned char eth_addr[ETH_ALEN] __aligned(2);
unsigned char flags;
unsigned char filter_mode;
+ unsigned char grp_query_rexmit_cnt;
struct hlist_head src_list;
unsigned int src_ents;
struct timer_list timer;
+ struct timer_list rexmit_timer;
struct hlist_node mglist;
struct rcu_head rcu;
@@ -868,6 +870,12 @@ static inline int br_multicast_igmp_type(const struct
sk_buff *skb)
{
return BR_INPUT_SKB_CB(skb)->igmp;
}
+
+static inline unsigned long br_multicast_lmqt(const struct net_bridge *br)
+{
+ return br->multicast_last_member_interval *
+ br->multicast_last_member_count;
+}
#else
static inline int br_multicast_rcv(struct net_bridge *br,
struct net_bridge_port *port,
--
2.25.4
Jakub Kicinski
2020-Sep-06 21:01 UTC
[Bridge] [PATCH net-next v3 06/15] net: bridge: mcast: add support for group query retransmit
On Sat, 5 Sep 2020 11:24:01 +0300 Nikolay Aleksandrov wrote:> We need to be able to retransmit group-specific and group-and-source > specific queries. The new timer takes care of those.What guarantees that timer will not use pg after free? Do timer callbacks hold the RCU read lock?