2021-05-09 19:46:53

by Linus Lüssing

[permalink] [raw]
Subject: [PATCH net-next v2 00/11] net: bridge: split IPv4/v6 mc router state and export for batman-adv

Hi,

The following patches are splitting the so far combined multicast router
state in the Linux bridge into two ones, one for IPv4 and one for IPv6,
for a more fine-grained detection of multicast routers. This avoids
sending IPv4 multicast packets to an IPv6-only multicast router and
avoids sending IPv6 multicast packets to an IPv4-only multicast router.
This also allows batman-adv to make use of the now split information in
the final patch.

The first eight patches prepare the bridge code to avoid duplicate
code or IPv6-#ifdef clutter for the multicast router state split. And
contain no functional changes yet.

The ninth patch then implements the IPv4+IPv6 multicast router state
split.

Patch number ten adds IPv4+IPv6 specific timers to the mdb netlink
router port dump, so that the timers validity can be checked individually
from userspace.

The final, eleventh patch exports this now per protocol family multicast
router state so that batman-adv can then later make full use of the
Multicast Router Discovery (MRD) support in the Linux bridge. The
batman-adv protocol format currently expects separate multicast router
states for IPv4 and IPv6, therefore it depends on the first patch.
batman-adv will then make use of this newly exported functions like
this[0].

Regards, Linus

[0]: https://git.open-mesh.org/batman-adv.git/shortlog/refs/heads/linus/multicast-routeable-mrd
-> https://git.open-mesh.org/batman-adv.git/commit/d4bed3a92427445708baeb1f2d1841c5fb816fd4

Changelog v2:

* split into multiple patches as suggested by Nikolay
* added helper functions to br_multicast_flood(), avoiding
IPv6 #ifdef clutter
* fixed reverse xmas tree ordering in br_rports_fill_info() and
added helper functions to avoid IPv6 #ifdef clutter
* Added a common br_multicast_add_router() and a helper function
to retrieve the correct slot to avoid duplicate code for an
ip4 and ip6 variant
* replaced the "1" and "2" constants in br_multicast_is_router()
with the appropriate enums
* added br_{ip4,ip6}_multicast_rport_del() wrappers to reduce
IPv6 #ifdef clutter
* added return values to br_*multicast_rport_del() to only notify
if the port was actually removed and did not race with a readdition
somewhere else
* added empty, void br_ip6_multicast_mark_router() if compiled
without IPv6, to reduce IPv6 #ifdef clutter



2021-05-09 19:47:02

by Linus Lüssing

[permalink] [raw]
Subject: [net-next v2 03/11] net: bridge: mcast: prepare mdb netlink for mcast router split

In preparation for the upcoming split of multicast router state into
their IPv4 and IPv6 variants and to avoid IPv6 #ifdef clutter later add
some inline functions for the protocol specific parts in the mdb router
netlink code. Also the we need iterate over the port instead of router
list to be able put one router port entry with both the IPv4 and IPv6
multicast router info later.

Signed-off-by: Linus Lüssing <[email protected]>
---
net/bridge/br_mdb.c | 39 ++++++++++++++++++++++++++++++++++-----
1 file changed, 34 insertions(+), 5 deletions(-)

diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index d61def8..6937d3b 100644
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -16,29 +16,58 @@

#include "br_private.h"

+static inline bool br_rports_have_mc_router(struct net_bridge *br)
+{
+ return !hlist_empty(&br->ip4_mc_router_list);
+}
+
+static inline bool
+br_ip4_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
+{
+ *timer = br_timer_value(&port->ip4_mc_router_timer);
+ return !hlist_unhashed(&port->ip4_rlist);
+}
+
+static inline bool
+br_ip6_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
+{
+ *timer = 0;
+ return false;
+}
+
static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
struct net_device *dev)
{
struct net_bridge *br = netdev_priv(dev);
- struct net_bridge_port *p;
+ bool have_ip4_mc_rtr, have_ip6_mc_rtr;
+ unsigned long ip4_timer, ip6_timer;
struct nlattr *nest, *port_nest;
+ struct net_bridge_port *p;

- if (!br->multicast_router || hlist_empty(&br->ip4_mc_router_list))
+ if (!br->multicast_router)
+ return 0;
+
+ if (!br_rports_have_mc_router(br))
return 0;

nest = nla_nest_start_noflag(skb, MDBA_ROUTER);
if (nest == NULL)
return -EMSGSIZE;

- hlist_for_each_entry_rcu(p, &br->ip4_mc_router_list, ip4_rlist) {
- if (!p)
+ list_for_each_entry_rcu(p, &br->port_list, list) {
+ have_ip4_mc_rtr = br_ip4_rports_get_timer(p, &ip4_timer);
+ have_ip6_mc_rtr = br_ip6_rports_get_timer(p, &ip6_timer);
+
+ if (!have_ip4_mc_rtr && !have_ip6_mc_rtr)
continue;
+
port_nest = nla_nest_start_noflag(skb, MDBA_ROUTER_PORT);
if (!port_nest)
goto fail;
+
if (nla_put_nohdr(skb, sizeof(u32), &p->dev->ifindex) ||
nla_put_u32(skb, MDBA_ROUTER_PATTR_TIMER,
- br_timer_value(&p->ip4_mc_router_timer)) ||
+ max(ip4_timer, ip6_timer)) ||
nla_put_u8(skb, MDBA_ROUTER_PATTR_TYPE,
p->multicast_router)) {
nla_nest_cancel(skb, port_nest);
--
2.31.0

2021-05-09 19:47:09

by Linus Lüssing

[permalink] [raw]
Subject: [net-next v2 04/11] net: bridge: mcast: prepare query reception for mcast router split

In preparation for the upcoming split of multicast router state into
their IPv4 and IPv6 variants and as the br_multicast_mark_router() will
be split for that remove the select querier wrapper and instead add
ip4 and ip6 variants for br_multicast_query_received().

Signed-off-by: Linus Lüssing <[email protected]>
---
net/bridge/br_multicast.c | 53 ++++++++++++++++++++-------------------
1 file changed, 27 insertions(+), 26 deletions(-)

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 6fe93a3..7edbbc9 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -2615,22 +2615,6 @@ update:
}
#endif

-static bool br_multicast_select_querier(struct net_bridge *br,
- struct net_bridge_port *port,
- struct br_ip *saddr)
-{
- switch (saddr->proto) {
- case htons(ETH_P_IP):
- return br_ip4_multicast_select_querier(br, port, saddr->src.ip4);
-#if IS_ENABLED(CONFIG_IPV6)
- case htons(ETH_P_IPV6):
- return br_ip6_multicast_select_querier(br, port, &saddr->src.ip6);
-#endif
- }
-
- return false;
-}
-
static void
br_multicast_update_query_timer(struct net_bridge *br,
struct bridge_mcast_other_query *query,
@@ -2708,19 +2692,36 @@ static void br_multicast_mark_router(struct net_bridge *br,
now + br->multicast_querier_interval);
}

-static void br_multicast_query_received(struct net_bridge *br,
- struct net_bridge_port *port,
- struct bridge_mcast_other_query *query,
- struct br_ip *saddr,
- unsigned long max_delay)
+static void
+br_ip4_multicast_query_received(struct net_bridge *br,
+ struct net_bridge_port *port,
+ struct bridge_mcast_other_query *query,
+ struct br_ip *saddr,
+ unsigned long max_delay)
{
- if (!br_multicast_select_querier(br, port, saddr))
+ if (!br_ip4_multicast_select_querier(br, port, saddr->src.ip4))
return;

br_multicast_update_query_timer(br, query, max_delay);
br_multicast_mark_router(br, port);
}

+#if IS_ENABLED(CONFIG_IPV6)
+static void
+br_ip6_multicast_query_received(struct net_bridge *br,
+ struct net_bridge_port *port,
+ struct bridge_mcast_other_query *query,
+ struct br_ip *saddr,
+ unsigned long max_delay)
+{
+ if (!br_ip6_multicast_select_querier(br, port, &saddr->src.ip6))
+ return;
+
+ br_multicast_update_query_timer(br, query, max_delay);
+ br_multicast_mark_router(br, port);
+}
+#endif
+
static void br_ip4_multicast_query(struct net_bridge *br,
struct net_bridge_port *port,
struct sk_buff *skb,
@@ -2768,8 +2769,8 @@ static void br_ip4_multicast_query(struct net_bridge *br,
saddr.proto = htons(ETH_P_IP);
saddr.src.ip4 = iph->saddr;

- br_multicast_query_received(br, port, &br->ip4_other_query,
- &saddr, max_delay);
+ br_ip4_multicast_query_received(br, port, &br->ip4_other_query,
+ &saddr, max_delay);
goto out;
}

@@ -2856,8 +2857,8 @@ static int br_ip6_multicast_query(struct net_bridge *br,
saddr.proto = htons(ETH_P_IPV6);
saddr.src.ip6 = ipv6_hdr(skb)->saddr;

- br_multicast_query_received(br, port, &br->ip6_other_query,
- &saddr, max_delay);
+ br_ip6_multicast_query_received(br, port, &br->ip6_other_query,
+ &saddr, max_delay);
goto out;
} else if (!group) {
goto out;
--
2.31.0

2021-05-09 19:47:56

by Linus Lüssing

[permalink] [raw]
Subject: [net-next v2 05/11] net: bridge: mcast: prepare is-router function for mcast router split

In preparation for the upcoming split of multicast router state into
their IPv4 and IPv6 variants make br_multicast_is_router() protocol
family aware.

Note that for now br_ip6_multicast_is_router() uses the currently still
common ip4_mc_router_timer for now. It will be renamed to
ip6_mc_router_timer later when the split is performed.

While at it also renames the "1" and "2" constants in
br_multicast_is_router() to the MDB_RTR_TYPE_TEMP_QUERY and
MDB_RTR_TYPE_PERM enums.

Signed-off-by: Linus Lüssing <[email protected]>
---
net/bridge/br_input.c | 2 +-
net/bridge/br_multicast.c | 5 +++--
net/bridge/br_private.h | 36 ++++++++++++++++++++++++++++++++----
3 files changed, 36 insertions(+), 7 deletions(-)

diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
index 8875e95..1f50630 100644
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c
@@ -132,7 +132,7 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
br_multicast_querier_exists(br, eth_hdr(skb), mdst)) {
if ((mdst && mdst->host_joined) ||
- br_multicast_is_router(br)) {
+ br_multicast_is_router(br, skb)) {
local_rcv = true;
br->dev->stats.multicast++;
}
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 7edbbc9..048b5b9 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1391,7 +1391,8 @@ static void br_multicast_local_router_expired(struct timer_list *t)
spin_lock(&br->multicast_lock);
if (br->multicast_router == MDB_RTR_TYPE_DISABLED ||
br->multicast_router == MDB_RTR_TYPE_PERM ||
- timer_pending(&br->ip4_mc_router_timer))
+ br_ip4_multicast_is_router(br) ||
+ br_ip6_multicast_is_router(br))
goto out;

br_mc_router_state_change(br, false);
@@ -3622,7 +3623,7 @@ bool br_multicast_router(const struct net_device *dev)
bool is_router;

spin_lock_bh(&br->multicast_lock);
- is_router = br_multicast_is_router(br);
+ is_router = br_multicast_is_router(br, NULL);
spin_unlock_bh(&br->multicast_lock);
return is_router;
}
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 26e91d2..ac5ca5b 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -864,11 +864,39 @@ static inline bool br_group_is_l2(const struct br_ip *group)
#define mlock_dereference(X, br) \
rcu_dereference_protected(X, lockdep_is_held(&br->multicast_lock))

-static inline bool br_multicast_is_router(struct net_bridge *br)
+static inline bool br_ip4_multicast_is_router(struct net_bridge *br)
{
- return br->multicast_router == 2 ||
- (br->multicast_router == 1 &&
- timer_pending(&br->ip4_mc_router_timer));
+ return timer_pending(&br->ip4_mc_router_timer);
+}
+
+static inline bool br_ip6_multicast_is_router(struct net_bridge *br)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+ return timer_pending(&br->ip4_mc_router_timer);
+#else
+ return false;
+#endif
+}
+
+static inline bool
+br_multicast_is_router(struct net_bridge *br, struct sk_buff *skb)
+{
+ if (br->multicast_router == MDB_RTR_TYPE_PERM)
+ return true;
+
+ if (br->multicast_router == MDB_RTR_TYPE_TEMP_QUERY) {
+ if (skb) {
+ if (skb->protocol == htons(ETH_P_IP))
+ return br_ip4_multicast_is_router(br);
+ else if (skb->protocol == htons(ETH_P_IPV6))
+ return br_ip6_multicast_is_router(br);
+ } else {
+ return br_ip4_multicast_is_router(br) ||
+ br_ip6_multicast_is_router(br);
+ }
+ }
+
+ return false;
}

static inline bool
--
2.31.0

2021-05-09 19:48:08

by Linus Lüssing

[permalink] [raw]
Subject: [net-next v2 06/11] net: bridge: mcast: prepare expiry functions for mcast router split

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

Signed-off-by: Linus Lüssing <[email protected]>
---
net/bridge/br_multicast.c | 31 ++++++++++++++++++++++---------
1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 048b5b9..6c844b2 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1354,16 +1354,16 @@ static int br_ip6_multicast_add_group(struct net_bridge *br,
}
#endif

-static void br_multicast_router_expired(struct timer_list *t)
+static void br_multicast_router_expired(struct net_bridge_port *port,
+ struct timer_list *t,
+ struct hlist_node *rlist)
{
- struct net_bridge_port *port =
- from_timer(port, t, ip4_mc_router_timer);
struct net_bridge *br = port->br;

spin_lock(&br->multicast_lock);
if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
port->multicast_router == MDB_RTR_TYPE_PERM ||
- timer_pending(&port->ip4_mc_router_timer))
+ timer_pending(t))
goto out;

__del_port_router(port);
@@ -1371,6 +1371,13 @@ out:
spin_unlock(&br->multicast_lock);
}

+static void br_ip4_multicast_router_expired(struct timer_list *t)
+{
+ struct net_bridge_port *port = from_timer(port, t, ip4_mc_router_timer);
+
+ br_multicast_router_expired(port, t, &port->ip4_rlist);
+}
+
static void br_mc_router_state_change(struct net_bridge *p,
bool is_mc_router)
{
@@ -1384,10 +1391,9 @@ static void br_mc_router_state_change(struct net_bridge *p,
switchdev_port_attr_set(p->dev, &attr, NULL);
}

-static void br_multicast_local_router_expired(struct timer_list *t)
+static void br_multicast_local_router_expired(struct net_bridge *br,
+ struct timer_list *timer)
{
- struct net_bridge *br = from_timer(br, t, ip4_mc_router_timer);
-
spin_lock(&br->multicast_lock);
if (br->multicast_router == MDB_RTR_TYPE_DISABLED ||
br->multicast_router == MDB_RTR_TYPE_PERM ||
@@ -1400,6 +1406,13 @@ out:
spin_unlock(&br->multicast_lock);
}

+static inline void br_ip4_multicast_local_router_expired(struct timer_list *t)
+{
+ struct net_bridge *br = from_timer(br, t, ip4_mc_router_timer);
+
+ br_multicast_local_router_expired(br, t);
+}
+
static void br_multicast_querier_expired(struct net_bridge *br,
struct bridge_mcast_own_query *query)
{
@@ -1615,7 +1628,7 @@ int br_multicast_add_port(struct net_bridge_port *port)
port->multicast_eht_hosts_limit = BR_MCAST_DEFAULT_EHT_HOSTS_LIMIT;

timer_setup(&port->ip4_mc_router_timer,
- br_multicast_router_expired, 0);
+ br_ip4_multicast_router_expired, 0);
timer_setup(&port->ip4_own_query.timer,
br_ip4_multicast_port_query_expired, 0);
#if IS_ENABLED(CONFIG_IPV6)
@@ -3319,7 +3332,7 @@ void br_multicast_init(struct net_bridge *br)

spin_lock_init(&br->multicast_lock);
timer_setup(&br->ip4_mc_router_timer,
- br_multicast_local_router_expired, 0);
+ br_ip4_multicast_local_router_expired, 0);
timer_setup(&br->ip4_other_query.timer,
br_ip4_multicast_querier_expired, 0);
timer_setup(&br->ip4_own_query.timer,
--
2.31.0

2021-05-09 19:48:23

by Linus Lüssing

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

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 <[email protected]>
---
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

2021-05-09 19:48:48

by Linus Lüssing

[permalink] [raw]
Subject: [net-next v2 10/11] net: bridge: mcast: add ip4+ip6 mcast router timers to mdb netlink

Now that we have split the multicast router state into two, one for IPv4
and one for IPv6, also add individual timers to the mdb netlink router
port dump. Leaving the old timer attribute for backwards compatibility.

Signed-off-by: Linus Lüssing <[email protected]>
---
include/uapi/linux/if_bridge.h | 2 ++
net/bridge/br_mdb.c | 8 +++++++-
2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h
index 13d59c5..6b56a75 100644
--- a/include/uapi/linux/if_bridge.h
+++ b/include/uapi/linux/if_bridge.h
@@ -627,6 +627,8 @@ enum {
MDBA_ROUTER_PATTR_UNSPEC,
MDBA_ROUTER_PATTR_TIMER,
MDBA_ROUTER_PATTR_TYPE,
+ MDBA_ROUTER_PATTR_INET_TIMER,
+ MDBA_ROUTER_PATTR_INET6_TIMER,
__MDBA_ROUTER_PATTR_MAX
};
#define MDBA_ROUTER_PATTR_MAX (__MDBA_ROUTER_PATTR_MAX - 1)
diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index 3c608da..2cdd9b6 100644
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -79,7 +79,13 @@ static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
nla_put_u32(skb, MDBA_ROUTER_PATTR_TIMER,
max(ip4_timer, ip6_timer)) ||
nla_put_u8(skb, MDBA_ROUTER_PATTR_TYPE,
- p->multicast_router)) {
+ p->multicast_router) ||
+ (have_ip4_mc_rtr &&
+ nla_put_u32(skb, MDBA_ROUTER_PATTR_INET_TIMER,
+ ip4_timer)) ||
+ (have_ip6_mc_rtr &&
+ nla_put_u32(skb, MDBA_ROUTER_PATTR_INET6_TIMER,
+ ip6_timer))) {
nla_nest_cancel(skb, port_nest);
goto fail;
}
--
2.31.0

2021-05-09 19:50:06

by Linus Lüssing

[permalink] [raw]
Subject: [net-next v2 08/11] net: bridge: mcast: split router port del+notify for mcast router split

In preparation for the upcoming split of multicast router state into
their IPv4 and IPv6 variants split router port deletion and notification
into two functions. When we disable a port for instance later we want to
only send one notification to switchdev and netlink for compatibility
and want to avoid sending one for IPv4 and one for IPv6. For that the
split is needed.

Signed-off-by: Linus Lüssing <[email protected]>
---
net/bridge/br_multicast.c | 40 ++++++++++++++++++++++++++++++---------
1 file changed, 31 insertions(+), 9 deletions(-)

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 839d21b..39854d5 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -60,7 +60,8 @@ static void br_ip4_multicast_leave_group(struct net_bridge *br,
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);
+static void
+br_multicast_rport_del_notify(struct net_bridge_port *p, bool deleted);
#if IS_ENABLED(CONFIG_IPV6)
static void br_ip6_multicast_leave_group(struct net_bridge *br,
struct net_bridge_port *port,
@@ -1354,11 +1355,26 @@ static int br_ip6_multicast_add_group(struct net_bridge *br,
}
#endif

+static bool br_multicast_rport_del(struct hlist_node *rlist)
+{
+ if (hlist_unhashed(rlist))
+ return false;
+
+ hlist_del_init_rcu(rlist);
+ return true;
+}
+
+static inline bool br_ip4_multicast_rport_del(struct net_bridge_port *p)
+{
+ return br_multicast_rport_del(&p->ip4_rlist);
+}
+
static void br_multicast_router_expired(struct net_bridge_port *port,
struct timer_list *t,
struct hlist_node *rlist)
{
struct net_bridge *br = port->br;
+ bool del;

spin_lock(&br->multicast_lock);
if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
@@ -1366,7 +1382,8 @@ static void br_multicast_router_expired(struct net_bridge_port *port,
timer_pending(t))
goto out;

- __del_port_router(port);
+ del = br_multicast_rport_del(rlist);
+ br_multicast_rport_del_notify(port, del);
out:
spin_unlock(&br->multicast_lock);
}
@@ -1706,19 +1723,20 @@ void br_multicast_disable_port(struct net_bridge_port *port)
struct net_bridge *br = port->br;
struct net_bridge_port_group *pg;
struct hlist_node *n;
+ bool del = false;

spin_lock(&br->multicast_lock);
hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
if (!(pg->flags & MDB_PG_FLAGS_PERMANENT))
br_multicast_find_del_pg(br, pg);

- __del_port_router(port);
-
+ del |= br_ip4_multicast_rport_del(port);
del_timer(&port->ip4_mc_router_timer);
del_timer(&port->ip4_own_query.timer);
#if IS_ENABLED(CONFIG_IPV6)
del_timer(&port->ip6_own_query.timer);
#endif
+ br_multicast_rport_del_notify(port, del);
spin_unlock(&br->multicast_lock);
}

@@ -3508,11 +3526,12 @@ int br_multicast_set_router(struct net_bridge *br, unsigned long val)
return err;
}

-static void __del_port_router(struct net_bridge_port *p)
+static void
+br_multicast_rport_del_notify(struct net_bridge_port *p, bool deleted)
{
- if (hlist_unhashed(&p->ip4_rlist))
+ if (!deleted)
return;
- hlist_del_init_rcu(&p->ip4_rlist);
+
br_rtr_notify(p->br->dev, p, RTM_DELMDB);
br_port_mc_router_state_change(p, false);

@@ -3526,6 +3545,7 @@ int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
struct net_bridge *br = p->br;
unsigned long now = jiffies;
int err = -EINVAL;
+ bool del = false;

spin_lock(&br->multicast_lock);
if (p->multicast_router == val) {
@@ -3539,12 +3559,14 @@ int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
switch (val) {
case MDB_RTR_TYPE_DISABLED:
p->multicast_router = MDB_RTR_TYPE_DISABLED;
- __del_port_router(p);
+ del |= br_ip4_multicast_rport_del(p);
del_timer(&p->ip4_mc_router_timer);
+ br_multicast_rport_del_notify(p, del);
break;
case MDB_RTR_TYPE_TEMP_QUERY:
p->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
- __del_port_router(p);
+ del |= br_ip4_multicast_rport_del(p);
+ br_multicast_rport_del_notify(p, del);
break;
case MDB_RTR_TYPE_PERM:
p->multicast_router = MDB_RTR_TYPE_PERM;
--
2.31.0

2021-05-09 19:50:43

by Linus Lüssing

[permalink] [raw]
Subject: [net-next v2 11/11] net: bridge: mcast: export multicast router presence adjacent to a port

To properly support routable multicast addresses in batman-adv in a
group-aware way, a batman-adv node needs to know if it serves multicast
routers.

This adds a function to the bridge to export this so that batman-adv
can then make full use of the Multicast Router Discovery capability of
the bridge.

Signed-off-by: Linus Lüssing <[email protected]>
---
net/bridge/br_multicast.c | 58 +++++++++++++++++++++++++++++++++++++++
1 file changed, 58 insertions(+)

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index b625fd6..e963de5 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -4061,6 +4061,64 @@ unlock:
}
EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);

+/**
+ * br_multicast_has_router_adjacent - Checks for a router behind a bridge port
+ * @dev: The bridge port adjacent to which to check for a multicast router
+ * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
+ *
+ * Checks whether the given interface has a bridge on top and if so returns
+ * true if a multicast router is behind one of the other ports of this
+ * bridge. Otherwise returns false.
+ */
+bool br_multicast_has_router_adjacent(struct net_device *dev, int proto)
+{
+ struct net_bridge_port *port, *p;
+ bool ret = false;
+
+ rcu_read_lock();
+ if (!netif_is_bridge_port(dev))
+ goto unlock;
+
+ port = br_port_get_rcu(dev);
+ if (!port || !port->br)
+ goto unlock;
+
+ switch (proto) {
+ case ETH_P_IP:
+ hlist_for_each_entry_rcu(p, &port->br->ip4_mc_router_list,
+ ip4_rlist) {
+ if (p == port)
+ continue;
+
+ ret = true;
+ goto unlock;
+ }
+ break;
+#if IS_ENABLED(CONFIG_IPV6)
+ case ETH_P_IPV6:
+ hlist_for_each_entry_rcu(p, &port->br->ip6_mc_router_list,
+ ip6_rlist) {
+ if (p == port)
+ continue;
+
+ ret = true;
+ goto unlock;
+ }
+ break;
+#endif
+ default:
+ /* when compiled without IPv6 support, be conservative and
+ * always assume presence of an IPv6 multicast router
+ */
+ ret = true;
+ }
+
+unlock:
+ rcu_read_unlock();
+ return ret;
+}
+EXPORT_SYMBOL_GPL(br_multicast_has_router_adjacent);
+
static void br_mcast_stats_add(struct bridge_mcast_stats __percpu *stats,
const struct sk_buff *skb, u8 type, u8 dir)
{
--
2.31.0

2021-05-09 19:50:43

by Linus Lüssing

[permalink] [raw]
Subject: [net-next v2 09/11] net: bridge: mcast: split multicast router state for IPv4 and IPv6

A multicast router for IPv4 does not imply that the same host also is a
multicast router for IPv6 and vice versa.

To reduce multicast traffic when a host is only a multicast router for
one of these two protocol families, keep router state for IPv4 and IPv6
separately. Similar to how querier state is kept separately.

For backwards compatibility for netlink and switchdev notifications
these two will still only notify if a port switched from either no
IPv4/IPv6 multicast router to any IPv4/IPv6 multicast router or the
other way round. However a full netlink MDB router dump will now also
include a multicast router timeout for both IPv4 and IPv6.

Signed-off-by: Linus Lüssing <[email protected]>
---
net/bridge/br_forward.c | 8 ++
net/bridge/br_mdb.c | 10 ++
net/bridge/br_multicast.c | 197 ++++++++++++++++++++++++++++++++++----
net/bridge/br_private.h | 6 +-
4 files changed, 201 insertions(+), 20 deletions(-)

diff --git a/net/bridge/br_forward.c b/net/bridge/br_forward.c
index b5ec4f9..31a02c5 100644
--- a/net/bridge/br_forward.c
+++ b/net/bridge/br_forward.c
@@ -266,11 +266,19 @@ static void maybe_deliver_addr(struct net_bridge_port *p, struct sk_buff *skb,

static inline struct hlist_node *
br_multicast_get_first_rport_node(struct net_bridge *b, struct sk_buff *skb) {
+#if IS_ENABLED(CONFIG_IPV6)
+ if (skb->protocol == htons(ETH_P_IPV6))
+ return rcu_dereference(hlist_first_rcu(&b->ip6_mc_router_list));
+#endif
return rcu_dereference(hlist_first_rcu(&b->ip4_mc_router_list));
}

static inline struct net_bridge_port *
br_multicast_rport_from_node(struct hlist_node *rp, struct sk_buff *skb) {
+#if IS_ENABLED(CONFIG_IPV6)
+ if (skb->protocol == htons(ETH_P_IPV6))
+ return hlist_entry_safe(rp, struct net_bridge_port, ip6_rlist);
+#endif
return hlist_entry_safe(rp, struct net_bridge_port, ip4_rlist);
}

diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index 6937d3b..3c608da 100644
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -18,7 +18,12 @@

static inline bool br_rports_have_mc_router(struct net_bridge *br)
{
+#if IS_ENABLED(CONFIG_IPV6)
+ return !hlist_empty(&br->ip4_mc_router_list) ||
+ !hlist_empty(&br->ip6_mc_router_list);
+#else
return !hlist_empty(&br->ip4_mc_router_list);
+#endif
}

static inline bool
@@ -31,8 +36,13 @@ br_ip4_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
static inline bool
br_ip6_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
{
+#if IS_ENABLED(CONFIG_IPV6)
+ *timer = br_timer_value(&port->ip6_mc_router_timer);
+ return !hlist_unhashed(&port->ip6_rlist);
+#else
*timer = 0;
return false;
+#endif
}

static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 39854d5..b625fd6 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -63,6 +63,8 @@ static void br_multicast_port_group_rexmit(struct timer_list *t);
static void
br_multicast_rport_del_notify(struct net_bridge_port *p, bool deleted);
#if IS_ENABLED(CONFIG_IPV6)
+static void br_ip6_multicast_add_router(struct net_bridge *br,
+ struct net_bridge_port *port);
static void br_ip6_multicast_leave_group(struct net_bridge *br,
struct net_bridge_port *port,
const struct in6_addr *group,
@@ -1369,6 +1371,15 @@ static inline bool br_ip4_multicast_rport_del(struct net_bridge_port *p)
return br_multicast_rport_del(&p->ip4_rlist);
}

+static inline bool br_ip6_multicast_rport_del(struct net_bridge_port *p)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+ return br_multicast_rport_del(&p->ip6_rlist);
+#else
+ return false;
+#endif
+}
+
static void br_multicast_router_expired(struct net_bridge_port *port,
struct timer_list *t,
struct hlist_node *rlist)
@@ -1395,6 +1406,15 @@ static void br_ip4_multicast_router_expired(struct timer_list *t)
br_multicast_router_expired(port, t, &port->ip4_rlist);
}

+#if IS_ENABLED(CONFIG_IPV6)
+static void br_ip6_multicast_router_expired(struct timer_list *t)
+{
+ struct net_bridge_port *port = from_timer(port, t, ip6_mc_router_timer);
+
+ br_multicast_router_expired(port, t, &port->ip6_rlist);
+}
+#endif
+
static void br_mc_router_state_change(struct net_bridge *p,
bool is_mc_router)
{
@@ -1430,6 +1450,15 @@ static inline void br_ip4_multicast_local_router_expired(struct timer_list *t)
br_multicast_local_router_expired(br, t);
}

+#if IS_ENABLED(CONFIG_IPV6)
+static inline void br_ip6_multicast_local_router_expired(struct timer_list *t)
+{
+ struct net_bridge *br = from_timer(br, t, ip6_mc_router_timer);
+
+ br_multicast_local_router_expired(br, t);
+}
+#endif
+
static void br_multicast_querier_expired(struct net_bridge *br,
struct bridge_mcast_own_query *query)
{
@@ -1649,6 +1678,8 @@ int br_multicast_add_port(struct net_bridge_port *port)
timer_setup(&port->ip4_own_query.timer,
br_ip4_multicast_port_query_expired, 0);
#if IS_ENABLED(CONFIG_IPV6)
+ timer_setup(&port->ip6_mc_router_timer,
+ br_ip6_multicast_router_expired, 0);
timer_setup(&port->ip6_own_query.timer,
br_ip6_multicast_port_query_expired, 0);
#endif
@@ -1681,6 +1712,9 @@ void br_multicast_del_port(struct net_bridge_port *port)
spin_unlock_bh(&br->multicast_lock);
br_multicast_gc(&deleted_head);
del_timer_sync(&port->ip4_mc_router_timer);
+#if IS_ENABLED(CONFIG_IPV6)
+ del_timer_sync(&port->ip6_mc_router_timer);
+#endif
free_percpu(port->mcast_stats);
}

@@ -1704,9 +1738,14 @@ static void __br_multicast_enable_port(struct net_bridge_port *port)
#if IS_ENABLED(CONFIG_IPV6)
br_multicast_enable(&port->ip6_own_query);
#endif
- if (port->multicast_router == MDB_RTR_TYPE_PERM &&
- hlist_unhashed(&port->ip4_rlist))
- br_ip4_multicast_add_router(br, port);
+ if (port->multicast_router == MDB_RTR_TYPE_PERM) {
+ if (hlist_unhashed(&port->ip4_rlist))
+ br_ip4_multicast_add_router(br, port);
+#if IS_ENABLED(CONFIG_IPV6)
+ if (hlist_unhashed(&port->ip6_rlist))
+ br_ip6_multicast_add_router(br, port);
+#endif
+ }
}

void br_multicast_enable_port(struct net_bridge_port *port)
@@ -1733,7 +1772,9 @@ void br_multicast_disable_port(struct net_bridge_port *port)
del |= br_ip4_multicast_rport_del(port);
del_timer(&port->ip4_mc_router_timer);
del_timer(&port->ip4_own_query.timer);
+ del |= br_ip6_multicast_rport_del(port);
#if IS_ENABLED(CONFIG_IPV6)
+ del_timer(&port->ip6_mc_router_timer);
del_timer(&port->ip6_own_query.timer);
#endif
br_multicast_rport_del_notify(port, del);
@@ -2671,11 +2712,19 @@ static void br_port_mc_router_state_change(struct net_bridge_port *p,
switchdev_port_attr_set(p->dev, &attr, NULL);
}

-/*
- * Add port to router_list
- * list is maintained ordered by pointer value
- * and locked by br->multicast_lock and RCU
- */
+static bool br_multicast_no_router_otherpf(struct net_bridge_port *port,
+ struct hlist_node *rnode)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+ if (rnode != &port->ip6_rlist)
+ return hlist_unhashed(&port->ip6_rlist);
+ else
+ return hlist_unhashed(&port->ip4_rlist);
+#else
+ return true;
+#endif
+}
+
static void br_multicast_add_router(struct net_bridge *br,
struct net_bridge_port *port,
struct hlist_node *slot,
@@ -2690,8 +2739,14 @@ static void br_multicast_add_router(struct net_bridge *br,
else
hlist_add_head_rcu(rlist, mc_router_list);

- br_rtr_notify(br->dev, port, RTM_NEWMDB);
- br_port_mc_router_state_change(port, true);
+ /* For backwards compatibility for now, only notify if we
+ * switched from no IPv4/IPv6 multicast router to a new
+ * IPv4 or IPv6 multicast router.
+ */
+ if (br_multicast_no_router_otherpf(port, rlist)) {
+ br_rtr_notify(br->dev, port, RTM_NEWMDB);
+ br_port_mc_router_state_change(port, true);
+ }
}

struct hlist_node *
@@ -2722,14 +2777,54 @@ static void br_ip4_multicast_add_router(struct net_bridge *br,
&br->ip4_mc_router_list);
}

-static void br_multicast_mark_router(struct net_bridge *br,
- struct net_bridge_port *port)
+#if IS_ENABLED(CONFIG_IPV6)
+struct hlist_node *
+br_ip6_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->ip6_mc_router_list, ip6_rlist) {
+ if ((unsigned long)port >= (unsigned long)p)
+ break;
+ slot = &p->ip6_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_ip6_multicast_add_router(struct net_bridge *br,
+ struct net_bridge_port *port)
+{
+ struct hlist_node *slot = br_ip6_multicast_get_rport_slot(br, port);
+
+ br_multicast_add_router(br, port, slot, &port->ip6_rlist,
+ &br->ip6_mc_router_list);
+}
+#else
+static inline void br_ip6_multicast_add_router(struct net_bridge *br,
+ struct net_bridge_port *port)
+{
+}
+#endif
+
+static void br_ip4_multicast_mark_router(struct net_bridge *br,
+ struct net_bridge_port *port)
{
unsigned long now = jiffies;

if (!port) {
if (br->multicast_router == MDB_RTR_TYPE_TEMP_QUERY) {
+#if IS_ENABLED(CONFIG_IPV6)
+ if (!timer_pending(&br->ip4_mc_router_timer) &&
+ !timer_pending(&br->ip6_mc_router_timer))
+#else
if (!timer_pending(&br->ip4_mc_router_timer))
+#endif
br_mc_router_state_change(br, true);
mod_timer(&br->ip4_mc_router_timer,
now + br->multicast_querier_interval);
@@ -2747,6 +2842,39 @@ static void br_multicast_mark_router(struct net_bridge *br,
now + br->multicast_querier_interval);
}

+#if IS_ENABLED(CONFIG_IPV6)
+static void br_ip6_multicast_mark_router(struct net_bridge *br,
+ struct net_bridge_port *port)
+{
+ unsigned long now = jiffies;
+
+ if (!port) {
+ if (br->multicast_router == MDB_RTR_TYPE_TEMP_QUERY) {
+ if (!timer_pending(&br->ip4_mc_router_timer) &&
+ !timer_pending(&br->ip6_mc_router_timer))
+ br_mc_router_state_change(br, true);
+ mod_timer(&br->ip6_mc_router_timer,
+ now + br->multicast_querier_interval);
+ }
+ return;
+ }
+
+ if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
+ port->multicast_router == MDB_RTR_TYPE_PERM)
+ return;
+
+ br_ip6_multicast_add_router(br, port);
+
+ mod_timer(&port->ip6_mc_router_timer,
+ now + br->multicast_querier_interval);
+}
+#else
+static inline void br_ip6_multicast_mark_router(struct net_bridge *br,
+ struct net_bridge_port *port)
+{
+}
+#endif
+
static void
br_ip4_multicast_query_received(struct net_bridge *br,
struct net_bridge_port *port,
@@ -2758,7 +2886,7 @@ br_ip4_multicast_query_received(struct net_bridge *br,
return;

br_multicast_update_query_timer(br, query, max_delay);
- br_multicast_mark_router(br, port);
+ br_ip4_multicast_mark_router(br, port);
}

#if IS_ENABLED(CONFIG_IPV6)
@@ -2773,7 +2901,7 @@ br_ip6_multicast_query_received(struct net_bridge *br,
return;

br_multicast_update_query_timer(br, query, max_delay);
- br_multicast_mark_router(br, port);
+ br_ip6_multicast_mark_router(br, port);
}
#endif

@@ -3143,7 +3271,7 @@ static void br_multicast_pim(struct net_bridge *br,
pim_hdr_type(pimhdr) != PIM_TYPE_HELLO)
return;

- br_multicast_mark_router(br, port);
+ br_ip4_multicast_mark_router(br, port);
}

static int br_ip4_multicast_mrd_rcv(struct net_bridge *br,
@@ -3154,7 +3282,7 @@ static int br_ip4_multicast_mrd_rcv(struct net_bridge *br,
igmp_hdr(skb)->type != IGMP_MRDISC_ADV)
return -ENOMSG;

- br_multicast_mark_router(br, port);
+ br_ip4_multicast_mark_router(br, port);

return 0;
}
@@ -3222,7 +3350,7 @@ static void br_ip6_multicast_mrd_rcv(struct net_bridge *br,
if (icmp6_hdr(skb)->icmp6_type != ICMPV6_MRDISC_ADV)
return;

- br_multicast_mark_router(br, port);
+ br_ip6_multicast_mark_router(br, port);
}

static int br_multicast_ipv6_rcv(struct net_bridge *br,
@@ -3379,6 +3507,8 @@ void br_multicast_init(struct net_bridge *br)
timer_setup(&br->ip4_own_query.timer,
br_ip4_multicast_query_expired, 0);
#if IS_ENABLED(CONFIG_IPV6)
+ timer_setup(&br->ip6_mc_router_timer,
+ br_ip6_multicast_local_router_expired, 0);
timer_setup(&br->ip6_other_query.timer,
br_ip6_multicast_querier_expired, 0);
timer_setup(&br->ip6_own_query.timer,
@@ -3476,6 +3606,7 @@ void br_multicast_stop(struct net_bridge *br)
del_timer_sync(&br->ip4_other_query.timer);
del_timer_sync(&br->ip4_own_query.timer);
#if IS_ENABLED(CONFIG_IPV6)
+ del_timer_sync(&br->ip6_mc_router_timer);
del_timer_sync(&br->ip6_other_query.timer);
del_timer_sync(&br->ip6_own_query.timer);
#endif
@@ -3510,6 +3641,9 @@ int br_multicast_set_router(struct net_bridge *br, unsigned long val)
case MDB_RTR_TYPE_PERM:
br_mc_router_state_change(br, val == MDB_RTR_TYPE_PERM);
del_timer(&br->ip4_mc_router_timer);
+#if IS_ENABLED(CONFIG_IPV6)
+ del_timer(&br->ip6_mc_router_timer);
+#endif
br->multicast_router = val;
err = 0;
break;
@@ -3532,6 +3666,16 @@ br_multicast_rport_del_notify(struct net_bridge_port *p, bool deleted)
if (!deleted)
return;

+ /* For backwards compatibility for now, only notify if there is
+ * no multicast router anymore for both IPv4 and IPv6.
+ */
+ if (!hlist_unhashed(&p->ip4_rlist))
+ return;
+#if IS_ENABLED(CONFIG_IPV6)
+ if (!hlist_unhashed(&p->ip6_rlist))
+ return;
+#endif
+
br_rtr_notify(p->br->dev, p, RTM_DELMDB);
br_port_mc_router_state_change(p, false);

@@ -3550,9 +3694,14 @@ int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
spin_lock(&br->multicast_lock);
if (p->multicast_router == val) {
/* Refresh the temp router port timer */
- if (p->multicast_router == MDB_RTR_TYPE_TEMP)
+ if (p->multicast_router == MDB_RTR_TYPE_TEMP) {
mod_timer(&p->ip4_mc_router_timer,
now + br->multicast_querier_interval);
+#if IS_ENABLED(CONFIG_IPV6)
+ mod_timer(&p->ip6_mc_router_timer,
+ now + br->multicast_querier_interval);
+#endif
+ }
err = 0;
goto unlock;
}
@@ -3561,21 +3710,31 @@ int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
p->multicast_router = MDB_RTR_TYPE_DISABLED;
del |= br_ip4_multicast_rport_del(p);
del_timer(&p->ip4_mc_router_timer);
+ del |= br_ip6_multicast_rport_del(p);
+#if IS_ENABLED(CONFIG_IPV6)
+ del_timer(&p->ip6_mc_router_timer);
+#endif
br_multicast_rport_del_notify(p, del);
break;
case MDB_RTR_TYPE_TEMP_QUERY:
p->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
del |= br_ip4_multicast_rport_del(p);
+ del |= br_ip6_multicast_rport_del(p);
br_multicast_rport_del_notify(p, del);
break;
case MDB_RTR_TYPE_PERM:
p->multicast_router = MDB_RTR_TYPE_PERM;
del_timer(&p->ip4_mc_router_timer);
br_ip4_multicast_add_router(br, p);
+#if IS_ENABLED(CONFIG_IPV6)
+ del_timer(&p->ip6_mc_router_timer);
+#endif
+ br_ip6_multicast_add_router(br, p);
break;
case MDB_RTR_TYPE_TEMP:
p->multicast_router = MDB_RTR_TYPE_TEMP;
- br_multicast_mark_router(br, p);
+ br_ip4_multicast_mark_router(br, p);
+ br_ip6_multicast_mark_router(br, p);
break;
default:
goto unlock;
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index ac5ca5b..5194210 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -311,6 +311,8 @@ struct net_bridge_port {
struct hlist_node ip4_rlist;
#if IS_ENABLED(CONFIG_IPV6)
struct bridge_mcast_own_query ip6_own_query;
+ struct timer_list ip6_mc_router_timer;
+ struct hlist_node ip6_rlist;
#endif /* IS_ENABLED(CONFIG_IPV6) */
u32 multicast_eht_hosts_limit;
u32 multicast_eht_hosts_cnt;
@@ -457,6 +459,8 @@ struct net_bridge {
struct bridge_mcast_querier ip4_querier;
struct bridge_mcast_stats __percpu *mcast_stats;
#if IS_ENABLED(CONFIG_IPV6)
+ struct hlist_head ip6_mc_router_list;
+ struct timer_list ip6_mc_router_timer;
struct bridge_mcast_other_query ip6_other_query;
struct bridge_mcast_own_query ip6_own_query;
struct bridge_mcast_querier ip6_querier;
@@ -872,7 +876,7 @@ static inline bool br_ip4_multicast_is_router(struct net_bridge *br)
static inline bool br_ip6_multicast_is_router(struct net_bridge *br)
{
#if IS_ENABLED(CONFIG_IPV6)
- return timer_pending(&br->ip4_mc_router_timer);
+ return timer_pending(&br->ip6_mc_router_timer);
#else
return false;
#endif
--
2.31.0

2021-05-11 09:15:13

by Nikolay Aleksandrov

[permalink] [raw]
Subject: Re: [net-next v2 03/11] net: bridge: mcast: prepare mdb netlink for mcast router split

On 09/05/2021 22:45, Linus Lüssing wrote:
> In preparation for the upcoming split of multicast router state into
> their IPv4 and IPv6 variants and to avoid IPv6 #ifdef clutter later add
> some inline functions for the protocol specific parts in the mdb router
> netlink code. Also the we need iterate over the port instead of router
> list to be able put one router port entry with both the IPv4 and IPv6
> multicast router info later.
>
> Signed-off-by: Linus Lüssing <[email protected]>
> ---
> net/bridge/br_mdb.c | 39 ++++++++++++++++++++++++++++++++++-----
> 1 file changed, 34 insertions(+), 5 deletions(-)
>
> diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
> index d61def8..6937d3b 100644
> --- a/net/bridge/br_mdb.c
> +++ b/net/bridge/br_mdb.c
> @@ -16,29 +16,58 @@
>
> #include "br_private.h"
>
> +static inline bool br_rports_have_mc_router(struct net_bridge *br)
> +{
> + return !hlist_empty(&br->ip4_mc_router_list);
> +}
> +
> +static inline bool
> +br_ip4_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
> +{
> + *timer = br_timer_value(&port->ip4_mc_router_timer);
> + return !hlist_unhashed(&port->ip4_rlist);
> +}
> +
> +static inline bool
> +br_ip6_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
> +{
> + *timer = 0;
> + return false;
> +}
> +

Same comment about inlines in .c files, please move them to br_private.h

> static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
> struct net_device *dev)
> {
> struct net_bridge *br = netdev_priv(dev);
> - struct net_bridge_port *p;
> + bool have_ip4_mc_rtr, have_ip6_mc_rtr;
> + unsigned long ip4_timer, ip6_timer;
> struct nlattr *nest, *port_nest;
> + struct net_bridge_port *p;
>
> - if (!br->multicast_router || hlist_empty(&br->ip4_mc_router_list))
> + if (!br->multicast_router)
> + return 0;
> +
> + if (!br_rports_have_mc_router(br))
> return 0;
>
> nest = nla_nest_start_noflag(skb, MDBA_ROUTER);
> if (nest == NULL)
> return -EMSGSIZE;
>
> - hlist_for_each_entry_rcu(p, &br->ip4_mc_router_list, ip4_rlist) {
> - if (!p)
> + list_for_each_entry_rcu(p, &br->port_list, list) {
> + have_ip4_mc_rtr = br_ip4_rports_get_timer(p, &ip4_timer);
> + have_ip6_mc_rtr = br_ip6_rports_get_timer(p, &ip6_timer);
> +
> + if (!have_ip4_mc_rtr && !have_ip6_mc_rtr)
> continue;
> +
> port_nest = nla_nest_start_noflag(skb, MDBA_ROUTER_PORT);
> if (!port_nest)
> goto fail;
> +
> if (nla_put_nohdr(skb, sizeof(u32), &p->dev->ifindex) ||
> nla_put_u32(skb, MDBA_ROUTER_PATTR_TIMER,
> - br_timer_value(&p->ip4_mc_router_timer)) ||
> + max(ip4_timer, ip6_timer)) ||
> nla_put_u8(skb, MDBA_ROUTER_PATTR_TYPE,
> p->multicast_router)) {
> nla_nest_cancel(skb, port_nest);
>

2021-05-11 09:16:10

by Nikolay Aleksandrov

[permalink] [raw]
Subject: Re: [net-next v2 04/11] net: bridge: mcast: prepare query reception for mcast router split

On 09/05/2021 22:45, Linus Lüssing wrote:
> In preparation for the upcoming split of multicast router state into
> their IPv4 and IPv6 variants and as the br_multicast_mark_router() will
> be split for that remove the select querier wrapper and instead add
> ip4 and ip6 variants for br_multicast_query_received().
>
> Signed-off-by: Linus Lüssing <[email protected]>
> ---
> net/bridge/br_multicast.c | 53 ++++++++++++++++++++-------------------
> 1 file changed, 27 insertions(+), 26 deletions(-)
>

Acked-by: Nikolay Aleksandrov <[email protected]>

> diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
> index 6fe93a3..7edbbc9 100644
> --- a/net/bridge/br_multicast.c
> +++ b/net/bridge/br_multicast.c
> @@ -2615,22 +2615,6 @@ update:
> }
> #endif
>
> -static bool br_multicast_select_querier(struct net_bridge *br,
> - struct net_bridge_port *port,
> - struct br_ip *saddr)
> -{
> - switch (saddr->proto) {
> - case htons(ETH_P_IP):
> - return br_ip4_multicast_select_querier(br, port, saddr->src.ip4);
> -#if IS_ENABLED(CONFIG_IPV6)
> - case htons(ETH_P_IPV6):
> - return br_ip6_multicast_select_querier(br, port, &saddr->src.ip6);
> -#endif
> - }
> -
> - return false;
> -}
> -
> static void
> br_multicast_update_query_timer(struct net_bridge *br,
> struct bridge_mcast_other_query *query,
> @@ -2708,19 +2692,36 @@ static void br_multicast_mark_router(struct net_bridge *br,
> now + br->multicast_querier_interval);
> }
>
> -static void br_multicast_query_received(struct net_bridge *br,
> - struct net_bridge_port *port,
> - struct bridge_mcast_other_query *query,
> - struct br_ip *saddr,
> - unsigned long max_delay)
> +static void
> +br_ip4_multicast_query_received(struct net_bridge *br,
> + struct net_bridge_port *port,
> + struct bridge_mcast_other_query *query,
> + struct br_ip *saddr,
> + unsigned long max_delay)
> {
> - if (!br_multicast_select_querier(br, port, saddr))
> + if (!br_ip4_multicast_select_querier(br, port, saddr->src.ip4))
> return;
>
> br_multicast_update_query_timer(br, query, max_delay);
> br_multicast_mark_router(br, port);
> }
>
> +#if IS_ENABLED(CONFIG_IPV6)
> +static void
> +br_ip6_multicast_query_received(struct net_bridge *br,
> + struct net_bridge_port *port,
> + struct bridge_mcast_other_query *query,
> + struct br_ip *saddr,
> + unsigned long max_delay)
> +{
> + if (!br_ip6_multicast_select_querier(br, port, &saddr->src.ip6))
> + return;
> +
> + br_multicast_update_query_timer(br, query, max_delay);
> + br_multicast_mark_router(br, port);
> +}
> +#endif
> +
> static void br_ip4_multicast_query(struct net_bridge *br,
> struct net_bridge_port *port,
> struct sk_buff *skb,
> @@ -2768,8 +2769,8 @@ static void br_ip4_multicast_query(struct net_bridge *br,
> saddr.proto = htons(ETH_P_IP);
> saddr.src.ip4 = iph->saddr;
>
> - br_multicast_query_received(br, port, &br->ip4_other_query,
> - &saddr, max_delay);
> + br_ip4_multicast_query_received(br, port, &br->ip4_other_query,
> + &saddr, max_delay);
> goto out;
> }
>
> @@ -2856,8 +2857,8 @@ static int br_ip6_multicast_query(struct net_bridge *br,
> saddr.proto = htons(ETH_P_IPV6);
> saddr.src.ip6 = ipv6_hdr(skb)->saddr;
>
> - br_multicast_query_received(br, port, &br->ip6_other_query,
> - &saddr, max_delay);
> + br_ip6_multicast_query_received(br, port, &br->ip6_other_query,
> + &saddr, max_delay);
> goto out;
> } else if (!group) {
> goto out;
>

2021-05-11 09:17:56

by Nikolay Aleksandrov

[permalink] [raw]
Subject: Re: [net-next v2 05/11] net: bridge: mcast: prepare is-router function for mcast router split

On 09/05/2021 22:45, Linus Lüssing wrote:
> In preparation for the upcoming split of multicast router state into
> their IPv4 and IPv6 variants make br_multicast_is_router() protocol
> family aware.
>
> Note that for now br_ip6_multicast_is_router() uses the currently still
> common ip4_mc_router_timer for now. It will be renamed to
> ip6_mc_router_timer later when the split is performed.
>
> While at it also renames the "1" and "2" constants in
> br_multicast_is_router() to the MDB_RTR_TYPE_TEMP_QUERY and
> MDB_RTR_TYPE_PERM enums.
>
> Signed-off-by: Linus Lüssing <[email protected]>
> ---
> net/bridge/br_input.c | 2 +-
> net/bridge/br_multicast.c | 5 +++--
> net/bridge/br_private.h | 36 ++++++++++++++++++++++++++++++++----
> 3 files changed, 36 insertions(+), 7 deletions(-)
>

Minor comment below, but either way:
Acked-by: Nikolay Aleksandrov <[email protected]>

> diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
> index 8875e95..1f50630 100644
> --- a/net/bridge/br_input.c
> +++ b/net/bridge/br_input.c
> @@ -132,7 +132,7 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
> if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
> br_multicast_querier_exists(br, eth_hdr(skb), mdst)) {
> if ((mdst && mdst->host_joined) ||
> - br_multicast_is_router(br)) {
> + br_multicast_is_router(br, skb)) {
> local_rcv = true;
> br->dev->stats.multicast++;
> }
> diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
> index 7edbbc9..048b5b9 100644
> --- a/net/bridge/br_multicast.c
> +++ b/net/bridge/br_multicast.c
> @@ -1391,7 +1391,8 @@ static void br_multicast_local_router_expired(struct timer_list *t)
> spin_lock(&br->multicast_lock);
> if (br->multicast_router == MDB_RTR_TYPE_DISABLED ||
> br->multicast_router == MDB_RTR_TYPE_PERM ||
> - timer_pending(&br->ip4_mc_router_timer))
> + br_ip4_multicast_is_router(br) ||
> + br_ip6_multicast_is_router(br))
> goto out;
>
> br_mc_router_state_change(br, false);
> @@ -3622,7 +3623,7 @@ bool br_multicast_router(const struct net_device *dev)
> bool is_router;
>
> spin_lock_bh(&br->multicast_lock);
> - is_router = br_multicast_is_router(br);
> + is_router = br_multicast_is_router(br, NULL);
> spin_unlock_bh(&br->multicast_lock);
> return is_router;
> }
> diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
> index 26e91d2..ac5ca5b 100644
> --- a/net/bridge/br_private.h
> +++ b/net/bridge/br_private.h
> @@ -864,11 +864,39 @@ static inline bool br_group_is_l2(const struct br_ip *group)
> #define mlock_dereference(X, br) \
> rcu_dereference_protected(X, lockdep_is_held(&br->multicast_lock))
>
> -static inline bool br_multicast_is_router(struct net_bridge *br)
> +static inline bool br_ip4_multicast_is_router(struct net_bridge *br)
> {
> - return br->multicast_router == 2 ||
> - (br->multicast_router == 1 &&
> - timer_pending(&br->ip4_mc_router_timer));
> + return timer_pending(&br->ip4_mc_router_timer);
> +}
> +
> +static inline bool br_ip6_multicast_is_router(struct net_bridge *br)
> +{
> +#if IS_ENABLED(CONFIG_IPV6)
> + return timer_pending(&br->ip4_mc_router_timer);
> +#else
> + return false;
> +#endif
> +}
> +
> +static inline bool
> +br_multicast_is_router(struct net_bridge *br, struct sk_buff *skb)
> +{
> + if (br->multicast_router == MDB_RTR_TYPE_PERM)
> + return true;
> +
> + if (br->multicast_router == MDB_RTR_TYPE_TEMP_QUERY) {
> + if (skb) {
> + if (skb->protocol == htons(ETH_P_IP))
> + return br_ip4_multicast_is_router(br);
> + else if (skb->protocol == htons(ETH_P_IPV6))
> + return br_ip6_multicast_is_router(br);
> + } else {
> + return br_ip4_multicast_is_router(br) ||
> + br_ip6_multicast_is_router(br);
> + }
> + }

Personally I'd prefer using a switch statement for br->multicast_router.

> +
> + return false;
> }
>
> static inline bool
>

2021-05-11 09:20:28

by Nikolay Aleksandrov

[permalink] [raw]
Subject: Re: [net-next v2 06/11] net: bridge: mcast: prepare expiry functions for mcast router split

On 09/05/2021 22:45, Linus Lüssing wrote:
> In preparation for the upcoming split of multicast router state into
> their IPv4 and IPv6 variants move the protocol specific timer access to
> an ip4 wrapper function.
>
> Signed-off-by: Linus Lüssing <[email protected]>
> ---
> net/bridge/br_multicast.c | 31 ++++++++++++++++++++++---------
> 1 file changed, 22 insertions(+), 9 deletions(-)
>
> diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
> index 048b5b9..6c844b2 100644
> --- a/net/bridge/br_multicast.c
> +++ b/net/bridge/br_multicast.c
> @@ -1354,16 +1354,16 @@ static int br_ip6_multicast_add_group(struct net_bridge *br,
> }
> #endif
>
> -static void br_multicast_router_expired(struct timer_list *t)
> +static void br_multicast_router_expired(struct net_bridge_port *port,
> + struct timer_list *t,
> + struct hlist_node *rlist)
> {
> - struct net_bridge_port *port =
> - from_timer(port, t, ip4_mc_router_timer);
> struct net_bridge *br = port->br;
>
> spin_lock(&br->multicast_lock);
> if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
> port->multicast_router == MDB_RTR_TYPE_PERM ||
> - timer_pending(&port->ip4_mc_router_timer))
> + timer_pending(t))
> goto out;
>
> __del_port_router(port);
> @@ -1371,6 +1371,13 @@ out:
> spin_unlock(&br->multicast_lock);
> }
>
> +static void br_ip4_multicast_router_expired(struct timer_list *t)
> +{
> + struct net_bridge_port *port = from_timer(port, t, ip4_mc_router_timer);
> +
> + br_multicast_router_expired(port, t, &port->ip4_rlist);
> +}
> +
> static void br_mc_router_state_change(struct net_bridge *p,
> bool is_mc_router)
> {
> @@ -1384,10 +1391,9 @@ static void br_mc_router_state_change(struct net_bridge *p,
> switchdev_port_attr_set(p->dev, &attr, NULL);
> }
>
> -static void br_multicast_local_router_expired(struct timer_list *t)
> +static void br_multicast_local_router_expired(struct net_bridge *br,
> + struct timer_list *timer)
> {
> - struct net_bridge *br = from_timer(br, t, ip4_mc_router_timer);
> -
> spin_lock(&br->multicast_lock);
> if (br->multicast_router == MDB_RTR_TYPE_DISABLED ||
> br->multicast_router == MDB_RTR_TYPE_PERM ||
> @@ -1400,6 +1406,13 @@ out:
> spin_unlock(&br->multicast_lock);
> }
>
> +static inline void br_ip4_multicast_local_router_expired(struct timer_list *t)
> +{
> + struct net_bridge *br = from_timer(br, t, ip4_mc_router_timer);
> +
> + br_multicast_local_router_expired(br, t);
> +}
> +

Same comment about inlines in .c files, please move them to br_private.h or drop the inline

> static void br_multicast_querier_expired(struct net_bridge *br,
> struct bridge_mcast_own_query *query)
> {
> @@ -1615,7 +1628,7 @@ int br_multicast_add_port(struct net_bridge_port *port)
> port->multicast_eht_hosts_limit = BR_MCAST_DEFAULT_EHT_HOSTS_LIMIT;
>
> timer_setup(&port->ip4_mc_router_timer,
> - br_multicast_router_expired, 0);
> + br_ip4_multicast_router_expired, 0);
> timer_setup(&port->ip4_own_query.timer,
> br_ip4_multicast_port_query_expired, 0);
> #if IS_ENABLED(CONFIG_IPV6)
> @@ -3319,7 +3332,7 @@ void br_multicast_init(struct net_bridge *br)
>
> spin_lock_init(&br->multicast_lock);
> timer_setup(&br->ip4_mc_router_timer,
> - br_multicast_local_router_expired, 0);
> + br_ip4_multicast_local_router_expired, 0);
> timer_setup(&br->ip4_other_query.timer,
> br_ip4_multicast_querier_expired, 0);
> timer_setup(&br->ip4_own_query.timer,
>

2021-05-11 09:21:34

by Nikolay Aleksandrov

[permalink] [raw]
Subject: Re: [net-next v2 08/11] net: bridge: mcast: split router port del+notify for mcast router split

On 09/05/2021 22:45, Linus Lüssing wrote:
> In preparation for the upcoming split of multicast router state into
> their IPv4 and IPv6 variants split router port deletion and notification
> into two functions. When we disable a port for instance later we want to
> only send one notification to switchdev and netlink for compatibility
> and want to avoid sending one for IPv4 and one for IPv6. For that the
> split is needed.
>
> Signed-off-by: Linus Lüssing <[email protected]>
> ---
> net/bridge/br_multicast.c | 40 ++++++++++++++++++++++++++++++---------
> 1 file changed, 31 insertions(+), 9 deletions(-)
>
> diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
> index 839d21b..39854d5 100644
> --- a/net/bridge/br_multicast.c
> +++ b/net/bridge/br_multicast.c
> @@ -60,7 +60,8 @@ static void br_ip4_multicast_leave_group(struct net_bridge *br,
> 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);
> +static void
> +br_multicast_rport_del_notify(struct net_bridge_port *p, bool deleted);
> #if IS_ENABLED(CONFIG_IPV6)
> static void br_ip6_multicast_leave_group(struct net_bridge *br,
> struct net_bridge_port *port,
> @@ -1354,11 +1355,26 @@ static int br_ip6_multicast_add_group(struct net_bridge *br,
> }
> #endif
>
> +static bool br_multicast_rport_del(struct hlist_node *rlist)
> +{
> + if (hlist_unhashed(rlist))
> + return false;
> +
> + hlist_del_init_rcu(rlist);
> + return true;
> +}
> +
> +static inline bool br_ip4_multicast_rport_del(struct net_bridge_port *p)
> +{
> + return br_multicast_rport_del(&p->ip4_rlist);
> +}
> +

Same comment about inline in .c files, either drop the inline or move it to br_private.h
For functions that are not critical for performance(fast-path) I'd just drop the inline
in the .c files and leave them there.

> static void br_multicast_router_expired(struct net_bridge_port *port,
> struct timer_list *t,
> struct hlist_node *rlist)
> {
> struct net_bridge *br = port->br;
> + bool del;
>
> spin_lock(&br->multicast_lock);
> if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
> @@ -1366,7 +1382,8 @@ static void br_multicast_router_expired(struct net_bridge_port *port,
> timer_pending(t))
> goto out;
>
> - __del_port_router(port);
> + del = br_multicast_rport_del(rlist);
> + br_multicast_rport_del_notify(port, del);
> out:
> spin_unlock(&br->multicast_lock);
> }
> @@ -1706,19 +1723,20 @@ void br_multicast_disable_port(struct net_bridge_port *port)
> struct net_bridge *br = port->br;
> struct net_bridge_port_group *pg;
> struct hlist_node *n;
> + bool del = false;
>
> spin_lock(&br->multicast_lock);
> hlist_for_each_entry_safe(pg, n, &port->mglist, mglist)
> if (!(pg->flags & MDB_PG_FLAGS_PERMANENT))
> br_multicast_find_del_pg(br, pg);
>
> - __del_port_router(port);
> -
> + del |= br_ip4_multicast_rport_del(port);
> del_timer(&port->ip4_mc_router_timer);
> del_timer(&port->ip4_own_query.timer);
> #if IS_ENABLED(CONFIG_IPV6)
> del_timer(&port->ip6_own_query.timer);
> #endif
> + br_multicast_rport_del_notify(port, del);
> spin_unlock(&br->multicast_lock);
> }
>
> @@ -3508,11 +3526,12 @@ int br_multicast_set_router(struct net_bridge *br, unsigned long val)
> return err;
> }
>
> -static void __del_port_router(struct net_bridge_port *p)
> +static void
> +br_multicast_rport_del_notify(struct net_bridge_port *p, bool deleted)
> {
> - if (hlist_unhashed(&p->ip4_rlist))
> + if (!deleted)
> return;
> - hlist_del_init_rcu(&p->ip4_rlist);
> +
> br_rtr_notify(p->br->dev, p, RTM_DELMDB);
> br_port_mc_router_state_change(p, false);
>
> @@ -3526,6 +3545,7 @@ int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
> struct net_bridge *br = p->br;
> unsigned long now = jiffies;
> int err = -EINVAL;
> + bool del = false;
>
> spin_lock(&br->multicast_lock);
> if (p->multicast_router == val) {
> @@ -3539,12 +3559,14 @@ int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
> switch (val) {
> case MDB_RTR_TYPE_DISABLED:
> p->multicast_router = MDB_RTR_TYPE_DISABLED;
> - __del_port_router(p);
> + del |= br_ip4_multicast_rport_del(p);
> del_timer(&p->ip4_mc_router_timer);
> + br_multicast_rport_del_notify(p, del);
> break;
> case MDB_RTR_TYPE_TEMP_QUERY:
> p->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
> - __del_port_router(p);
> + del |= br_ip4_multicast_rport_del(p);
> + br_multicast_rport_del_notify(p, del);
> break;
> case MDB_RTR_TYPE_PERM:
> p->multicast_router = MDB_RTR_TYPE_PERM;
>

2021-05-11 09:25:09

by Nikolay Aleksandrov

[permalink] [raw]
Subject: Re: [net-next v2 11/11] net: bridge: mcast: export multicast router presence adjacent to a port

On 09/05/2021 22:45, Linus Lüssing wrote:
> To properly support routable multicast addresses in batman-adv in a
> group-aware way, a batman-adv node needs to know if it serves multicast
> routers.
>
> This adds a function to the bridge to export this so that batman-adv
> can then make full use of the Multicast Router Discovery capability of
> the bridge.
>
> Signed-off-by: Linus Lüssing <[email protected]>
> ---
> net/bridge/br_multicast.c | 58 +++++++++++++++++++++++++++++++++++++++
> 1 file changed, 58 insertions(+)
>
> diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
> index b625fd6..e963de5 100644
> --- a/net/bridge/br_multicast.c
> +++ b/net/bridge/br_multicast.c
> @@ -4061,6 +4061,64 @@ unlock:
> }
> EXPORT_SYMBOL_GPL(br_multicast_has_querier_adjacent);
>
> +/**
> + * br_multicast_has_router_adjacent - Checks for a router behind a bridge port
> + * @dev: The bridge port adjacent to which to check for a multicast router
> + * @proto: The protocol family to check for: IGMP -> ETH_P_IP, MLD -> ETH_P_IPV6
> + *
> + * Checks whether the given interface has a bridge on top and if so returns
> + * true if a multicast router is behind one of the other ports of this
> + * bridge. Otherwise returns false.
> + */
> +bool br_multicast_has_router_adjacent(struct net_device *dev, int proto)
> +{
> + struct net_bridge_port *port, *p;
> + bool ret = false;
> +
> + rcu_read_lock();
> + if (!netif_is_bridge_port(dev))
> + goto unlock;
> +
> + port = br_port_get_rcu(dev);

You can combine both of netif_is_bridge_port and br_port_get_rcu() checks and use
br_port_get_check_rcu(). Then you can also drop the port->br check.


> + if (!port || !port->br)
> + goto unlock;
> +
> + switch (proto) {
> + case ETH_P_IP:
> + hlist_for_each_entry_rcu(p, &port->br->ip4_mc_router_list,
> + ip4_rlist) {
> + if (p == port)
> + continue;
> +
> + ret = true;
> + goto unlock;
> + }
> + break;
> +#if IS_ENABLED(CONFIG_IPV6)
> + case ETH_P_IPV6:
> + hlist_for_each_entry_rcu(p, &port->br->ip6_mc_router_list,
> + ip6_rlist) {
> + if (p == port)
> + continue;
> +
> + ret = true;
> + goto unlock;
> + }
> + break;
> +#endif
> + default:
> + /* when compiled without IPv6 support, be conservative and
> + * always assume presence of an IPv6 multicast router
> + */
> + ret = true;
> + }
> +
> +unlock:
> + rcu_read_unlock();
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(br_multicast_has_router_adjacent);
> +
> static void br_mcast_stats_add(struct bridge_mcast_stats __percpu *stats,
> const struct sk_buff *skb, u8 type, u8 dir)
> {
>

2021-05-11 09:31:54

by Nikolay Aleksandrov

[permalink] [raw]
Subject: Re: [net-next v2 09/11] net: bridge: mcast: split multicast router state for IPv4 and IPv6

On 09/05/2021 22:45, Linus Lüssing wrote:
> A multicast router for IPv4 does not imply that the same host also is a
> multicast router for IPv6 and vice versa.
>
> To reduce multicast traffic when a host is only a multicast router for
> one of these two protocol families, keep router state for IPv4 and IPv6
> separately. Similar to how querier state is kept separately.
>
> For backwards compatibility for netlink and switchdev notifications
> these two will still only notify if a port switched from either no
> IPv4/IPv6 multicast router to any IPv4/IPv6 multicast router or the
> other way round. However a full netlink MDB router dump will now also
> include a multicast router timeout for both IPv4 and IPv6.
>
> Signed-off-by: Linus Lüssing <[email protected]>
> ---
> net/bridge/br_forward.c | 8 ++
> net/bridge/br_mdb.c | 10 ++
> net/bridge/br_multicast.c | 197 ++++++++++++++++++++++++++++++++++----
> net/bridge/br_private.h | 6 +-
> 4 files changed, 201 insertions(+), 20 deletions(-)
>
> diff --git a/net/bridge/br_forward.c b/net/bridge/br_forward.c
> index b5ec4f9..31a02c5 100644
> --- a/net/bridge/br_forward.c
> +++ b/net/bridge/br_forward.c
> @@ -266,11 +266,19 @@ static void maybe_deliver_addr(struct net_bridge_port *p, struct sk_buff *skb,
>
> static inline struct hlist_node *
> br_multicast_get_first_rport_node(struct net_bridge *b, struct sk_buff *skb) {
> +#if IS_ENABLED(CONFIG_IPV6)
> + if (skb->protocol == htons(ETH_P_IPV6))
> + return rcu_dereference(hlist_first_rcu(&b->ip6_mc_router_list));
> +#endif
> return rcu_dereference(hlist_first_rcu(&b->ip4_mc_router_list));
> }
>
> static inline struct net_bridge_port *
> br_multicast_rport_from_node(struct hlist_node *rp, struct sk_buff *skb) {
> +#if IS_ENABLED(CONFIG_IPV6)
> + if (skb->protocol == htons(ETH_P_IPV6))
> + return hlist_entry_safe(rp, struct net_bridge_port, ip6_rlist);
> +#endif
> return hlist_entry_safe(rp, struct net_bridge_port, ip4_rlist);
> }
>
> diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
> index 6937d3b..3c608da 100644
> --- a/net/bridge/br_mdb.c
> +++ b/net/bridge/br_mdb.c
> @@ -18,7 +18,12 @@
>
> static inline bool br_rports_have_mc_router(struct net_bridge *br)
> {
> +#if IS_ENABLED(CONFIG_IPV6)
> + return !hlist_empty(&br->ip4_mc_router_list) ||
> + !hlist_empty(&br->ip6_mc_router_list);
> +#else
> return !hlist_empty(&br->ip4_mc_router_list);
> +#endif
> }
>
> static inline bool
> @@ -31,8 +36,13 @@ br_ip4_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
> static inline bool
> br_ip6_rports_get_timer(struct net_bridge_port *port, unsigned long *timer)
> {
> +#if IS_ENABLED(CONFIG_IPV6)
> + *timer = br_timer_value(&port->ip6_mc_router_timer);
> + return !hlist_unhashed(&port->ip6_rlist);
> +#else
> *timer = 0;
> return false;
> +#endif
> }
>
> static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
> diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
> index 39854d5..b625fd6 100644
> --- a/net/bridge/br_multicast.c
> +++ b/net/bridge/br_multicast.c
> @@ -63,6 +63,8 @@ static void br_multicast_port_group_rexmit(struct timer_list *t);
> static void
> br_multicast_rport_del_notify(struct net_bridge_port *p, bool deleted);
> #if IS_ENABLED(CONFIG_IPV6)
> +static void br_ip6_multicast_add_router(struct net_bridge *br,
> + struct net_bridge_port *port);
> static void br_ip6_multicast_leave_group(struct net_bridge *br,
> struct net_bridge_port *port,
> const struct in6_addr *group,
> @@ -1369,6 +1371,15 @@ static inline bool br_ip4_multicast_rport_del(struct net_bridge_port *p)
> return br_multicast_rport_del(&p->ip4_rlist);
> }
>
> +static inline bool br_ip6_multicast_rport_del(struct net_bridge_port *p)
> +{
> +#if IS_ENABLED(CONFIG_IPV6)
> + return br_multicast_rport_del(&p->ip6_rlist);
> +#else
> + return false;
> +#endif
> +}
> +
> static void br_multicast_router_expired(struct net_bridge_port *port,
> struct timer_list *t,
> struct hlist_node *rlist)
> @@ -1395,6 +1406,15 @@ static void br_ip4_multicast_router_expired(struct timer_list *t)
> br_multicast_router_expired(port, t, &port->ip4_rlist);
> }
>
> +#if IS_ENABLED(CONFIG_IPV6)
> +static void br_ip6_multicast_router_expired(struct timer_list *t)
> +{
> + struct net_bridge_port *port = from_timer(port, t, ip6_mc_router_timer);
> +
> + br_multicast_router_expired(port, t, &port->ip6_rlist);
> +}
> +#endif
> +
> static void br_mc_router_state_change(struct net_bridge *p,
> bool is_mc_router)
> {
> @@ -1430,6 +1450,15 @@ static inline void br_ip4_multicast_local_router_expired(struct timer_list *t)
> br_multicast_local_router_expired(br, t);
> }
>
> +#if IS_ENABLED(CONFIG_IPV6)
> +static inline void br_ip6_multicast_local_router_expired(struct timer_list *t)
> +{
> + struct net_bridge *br = from_timer(br, t, ip6_mc_router_timer);
> +
> + br_multicast_local_router_expired(br, t);
> +}
> +#endif
> +
> static void br_multicast_querier_expired(struct net_bridge *br,
> struct bridge_mcast_own_query *query)
> {
> @@ -1649,6 +1678,8 @@ int br_multicast_add_port(struct net_bridge_port *port)
> timer_setup(&port->ip4_own_query.timer,
> br_ip4_multicast_port_query_expired, 0);
> #if IS_ENABLED(CONFIG_IPV6)
> + timer_setup(&port->ip6_mc_router_timer,
> + br_ip6_multicast_router_expired, 0);
> timer_setup(&port->ip6_own_query.timer,
> br_ip6_multicast_port_query_expired, 0);
> #endif
> @@ -1681,6 +1712,9 @@ void br_multicast_del_port(struct net_bridge_port *port)
> spin_unlock_bh(&br->multicast_lock);
> br_multicast_gc(&deleted_head);
> del_timer_sync(&port->ip4_mc_router_timer);
> +#if IS_ENABLED(CONFIG_IPV6)
> + del_timer_sync(&port->ip6_mc_router_timer);
> +#endif
> free_percpu(port->mcast_stats);
> }
>
> @@ -1704,9 +1738,14 @@ static void __br_multicast_enable_port(struct net_bridge_port *port)
> #if IS_ENABLED(CONFIG_IPV6)
> br_multicast_enable(&port->ip6_own_query);
> #endif
> - if (port->multicast_router == MDB_RTR_TYPE_PERM &&
> - hlist_unhashed(&port->ip4_rlist))
> - br_ip4_multicast_add_router(br, port);
> + if (port->multicast_router == MDB_RTR_TYPE_PERM) {
> + if (hlist_unhashed(&port->ip4_rlist))
> + br_ip4_multicast_add_router(br, port);
> +#if IS_ENABLED(CONFIG_IPV6)
> + if (hlist_unhashed(&port->ip6_rlist))
> + br_ip6_multicast_add_router(br, port);
> +#endif
> + }
> }
>
> void br_multicast_enable_port(struct net_bridge_port *port)
> @@ -1733,7 +1772,9 @@ void br_multicast_disable_port(struct net_bridge_port *port)
> del |= br_ip4_multicast_rport_del(port);
> del_timer(&port->ip4_mc_router_timer);
> del_timer(&port->ip4_own_query.timer);
> + del |= br_ip6_multicast_rport_del(port);
> #if IS_ENABLED(CONFIG_IPV6)
> + del_timer(&port->ip6_mc_router_timer);
> del_timer(&port->ip6_own_query.timer);
> #endif
> br_multicast_rport_del_notify(port, del);
> @@ -2671,11 +2712,19 @@ static void br_port_mc_router_state_change(struct net_bridge_port *p,
> switchdev_port_attr_set(p->dev, &attr, NULL);
> }
>
> -/*
> - * Add port to router_list
> - * list is maintained ordered by pointer value
> - * and locked by br->multicast_lock and RCU
> - */
> +static bool br_multicast_no_router_otherpf(struct net_bridge_port *port,
> + struct hlist_node *rnode)
> +{
> +#if IS_ENABLED(CONFIG_IPV6)
> + if (rnode != &port->ip6_rlist)
> + return hlist_unhashed(&port->ip6_rlist);
> + else
> + return hlist_unhashed(&port->ip4_rlist);
> +#else
> + return true;
> +#endif
> +}
> +
> static void br_multicast_add_router(struct net_bridge *br,
> struct net_bridge_port *port,
> struct hlist_node *slot,
> @@ -2690,8 +2739,14 @@ static void br_multicast_add_router(struct net_bridge *br,
> else
> hlist_add_head_rcu(rlist, mc_router_list);
>
> - br_rtr_notify(br->dev, port, RTM_NEWMDB);
> - br_port_mc_router_state_change(port, true);
> + /* For backwards compatibility for now, only notify if we
> + * switched from no IPv4/IPv6 multicast router to a new
> + * IPv4 or IPv6 multicast router.
> + */
> + if (br_multicast_no_router_otherpf(port, rlist)) {
> + br_rtr_notify(br->dev, port, RTM_NEWMDB);
> + br_port_mc_router_state_change(port, true);
> + }
> }
>
> struct hlist_node *
> @@ -2722,14 +2777,54 @@ static void br_ip4_multicast_add_router(struct net_bridge *br,
> &br->ip4_mc_router_list);
> }
>
> -static void br_multicast_mark_router(struct net_bridge *br,
> - struct net_bridge_port *port)
> +#if IS_ENABLED(CONFIG_IPV6)
> +struct hlist_node *
> +br_ip6_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->ip6_mc_router_list, ip6_rlist) {
> + if ((unsigned long)port >= (unsigned long)p)
> + break;
> + slot = &p->ip6_rlist;
> + }
> +
> + return slot;
> +}

The ip4/ip6 get_rport_slot functions are identical, why not add a list pointer
and use one function ?

> +
> +/* Add port to router_list
> + * list is maintained ordered by pointer value
> + * and locked by br->multicast_lock and RCU
> + */
> +static void br_ip6_multicast_add_router(struct net_bridge *br,
> + struct net_bridge_port *port)
> +{
> + struct hlist_node *slot = br_ip6_multicast_get_rport_slot(br, port);
> +
> + br_multicast_add_router(br, port, slot, &port->ip6_rlist,
> + &br->ip6_mc_router_list);
> +}
> +#else
> +static inline void br_ip6_multicast_add_router(struct net_bridge *br,
> + struct net_bridge_port *port)
> +{
> +}

Actually that goes for multicast_add_router, too.

I'm saying all this because soon I'll be adding per-vlan multicast router support
and these will be reusable there without any modification if they can take any list.
Also it'll be easier to maintain one set of functions instead of multiple identical ones.

> +#endif
> +
> +static void br_ip4_multicast_mark_router(struct net_bridge *br,
> + struct net_bridge_port *port)
> {
> unsigned long now = jiffies;
>
> if (!port) {
> if (br->multicast_router == MDB_RTR_TYPE_TEMP_QUERY) {
> +#if IS_ENABLED(CONFIG_IPV6)
> + if (!timer_pending(&br->ip4_mc_router_timer) &&
> + !timer_pending(&br->ip6_mc_router_timer))
> +#else
> if (!timer_pending(&br->ip4_mc_router_timer))
> +#endif
> br_mc_router_state_change(br, true);
> mod_timer(&br->ip4_mc_router_timer,
> now + br->multicast_querier_interval);
> @@ -2747,6 +2842,39 @@ static void br_multicast_mark_router(struct net_bridge *br,
> now + br->multicast_querier_interval);
> }
>
> +#if IS_ENABLED(CONFIG_IPV6)
> +static void br_ip6_multicast_mark_router(struct net_bridge *br,
> + struct net_bridge_port *port)
> +{
> + unsigned long now = jiffies;
> +
> + if (!port) {
> + if (br->multicast_router == MDB_RTR_TYPE_TEMP_QUERY) {
> + if (!timer_pending(&br->ip4_mc_router_timer) &&
> + !timer_pending(&br->ip6_mc_router_timer))
> + br_mc_router_state_change(br, true);
> + mod_timer(&br->ip6_mc_router_timer,
> + now + br->multicast_querier_interval);
> + }
> + return;
> + }
> +
> + if (port->multicast_router == MDB_RTR_TYPE_DISABLED ||
> + port->multicast_router == MDB_RTR_TYPE_PERM)
> + return;
> +
> + br_ip6_multicast_add_router(br, port);
> +
> + mod_timer(&port->ip6_mc_router_timer,
> + now + br->multicast_querier_interval);
> +}
> +#else
> +static inline void br_ip6_multicast_mark_router(struct net_bridge *br,
> + struct net_bridge_port *port)
> +{
> +}
> +#endif
> +
> static void
> br_ip4_multicast_query_received(struct net_bridge *br,
> struct net_bridge_port *port,
> @@ -2758,7 +2886,7 @@ br_ip4_multicast_query_received(struct net_bridge *br,
> return;
>
> br_multicast_update_query_timer(br, query, max_delay);
> - br_multicast_mark_router(br, port);
> + br_ip4_multicast_mark_router(br, port);
> }
>
> #if IS_ENABLED(CONFIG_IPV6)
> @@ -2773,7 +2901,7 @@ br_ip6_multicast_query_received(struct net_bridge *br,
> return;
>
> br_multicast_update_query_timer(br, query, max_delay);
> - br_multicast_mark_router(br, port);
> + br_ip6_multicast_mark_router(br, port);
> }
> #endif
>
> @@ -3143,7 +3271,7 @@ static void br_multicast_pim(struct net_bridge *br,
> pim_hdr_type(pimhdr) != PIM_TYPE_HELLO)
> return;
>
> - br_multicast_mark_router(br, port);
> + br_ip4_multicast_mark_router(br, port);
> }
>
> static int br_ip4_multicast_mrd_rcv(struct net_bridge *br,
> @@ -3154,7 +3282,7 @@ static int br_ip4_multicast_mrd_rcv(struct net_bridge *br,
> igmp_hdr(skb)->type != IGMP_MRDISC_ADV)
> return -ENOMSG;
>
> - br_multicast_mark_router(br, port);
> + br_ip4_multicast_mark_router(br, port);
>
> return 0;
> }
> @@ -3222,7 +3350,7 @@ static void br_ip6_multicast_mrd_rcv(struct net_bridge *br,
> if (icmp6_hdr(skb)->icmp6_type != ICMPV6_MRDISC_ADV)
> return;
>
> - br_multicast_mark_router(br, port);
> + br_ip6_multicast_mark_router(br, port);
> }
>
> static int br_multicast_ipv6_rcv(struct net_bridge *br,
> @@ -3379,6 +3507,8 @@ void br_multicast_init(struct net_bridge *br)
> timer_setup(&br->ip4_own_query.timer,
> br_ip4_multicast_query_expired, 0);
> #if IS_ENABLED(CONFIG_IPV6)
> + timer_setup(&br->ip6_mc_router_timer,
> + br_ip6_multicast_local_router_expired, 0);
> timer_setup(&br->ip6_other_query.timer,
> br_ip6_multicast_querier_expired, 0);
> timer_setup(&br->ip6_own_query.timer,
> @@ -3476,6 +3606,7 @@ void br_multicast_stop(struct net_bridge *br)
> del_timer_sync(&br->ip4_other_query.timer);
> del_timer_sync(&br->ip4_own_query.timer);
> #if IS_ENABLED(CONFIG_IPV6)
> + del_timer_sync(&br->ip6_mc_router_timer);
> del_timer_sync(&br->ip6_other_query.timer);
> del_timer_sync(&br->ip6_own_query.timer);
> #endif
> @@ -3510,6 +3641,9 @@ int br_multicast_set_router(struct net_bridge *br, unsigned long val)
> case MDB_RTR_TYPE_PERM:
> br_mc_router_state_change(br, val == MDB_RTR_TYPE_PERM);
> del_timer(&br->ip4_mc_router_timer);
> +#if IS_ENABLED(CONFIG_IPV6)
> + del_timer(&br->ip6_mc_router_timer);
> +#endif
> br->multicast_router = val;
> err = 0;
> break;
> @@ -3532,6 +3666,16 @@ br_multicast_rport_del_notify(struct net_bridge_port *p, bool deleted)
> if (!deleted)
> return;
>
> + /* For backwards compatibility for now, only notify if there is
> + * no multicast router anymore for both IPv4 and IPv6.
> + */
> + if (!hlist_unhashed(&p->ip4_rlist))
> + return;
> +#if IS_ENABLED(CONFIG_IPV6)
> + if (!hlist_unhashed(&p->ip6_rlist))
> + return;
> +#endif
> +
> br_rtr_notify(p->br->dev, p, RTM_DELMDB);
> br_port_mc_router_state_change(p, false);
>
> @@ -3550,9 +3694,14 @@ int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
> spin_lock(&br->multicast_lock);
> if (p->multicast_router == val) {
> /* Refresh the temp router port timer */
> - if (p->multicast_router == MDB_RTR_TYPE_TEMP)
> + if (p->multicast_router == MDB_RTR_TYPE_TEMP) {
> mod_timer(&p->ip4_mc_router_timer,
> now + br->multicast_querier_interval);
> +#if IS_ENABLED(CONFIG_IPV6)
> + mod_timer(&p->ip6_mc_router_timer,
> + now + br->multicast_querier_interval);
> +#endif
> + }
> err = 0;
> goto unlock;
> }
> @@ -3561,21 +3710,31 @@ int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val)
> p->multicast_router = MDB_RTR_TYPE_DISABLED;
> del |= br_ip4_multicast_rport_del(p);
> del_timer(&p->ip4_mc_router_timer);
> + del |= br_ip6_multicast_rport_del(p);
> +#if IS_ENABLED(CONFIG_IPV6)
> + del_timer(&p->ip6_mc_router_timer);
> +#endif
> br_multicast_rport_del_notify(p, del);
> break;
> case MDB_RTR_TYPE_TEMP_QUERY:
> p->multicast_router = MDB_RTR_TYPE_TEMP_QUERY;
> del |= br_ip4_multicast_rport_del(p);
> + del |= br_ip6_multicast_rport_del(p);
> br_multicast_rport_del_notify(p, del);
> break;
> case MDB_RTR_TYPE_PERM:
> p->multicast_router = MDB_RTR_TYPE_PERM;
> del_timer(&p->ip4_mc_router_timer);
> br_ip4_multicast_add_router(br, p);
> +#if IS_ENABLED(CONFIG_IPV6)
> + del_timer(&p->ip6_mc_router_timer);
> +#endif
> + br_ip6_multicast_add_router(br, p);
> break;
> case MDB_RTR_TYPE_TEMP:
> p->multicast_router = MDB_RTR_TYPE_TEMP;
> - br_multicast_mark_router(br, p);
> + br_ip4_multicast_mark_router(br, p);
> + br_ip6_multicast_mark_router(br, p);
> break;
> default:
> goto unlock;
> diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
> index ac5ca5b..5194210 100644
> --- a/net/bridge/br_private.h
> +++ b/net/bridge/br_private.h
> @@ -311,6 +311,8 @@ struct net_bridge_port {
> struct hlist_node ip4_rlist;
> #if IS_ENABLED(CONFIG_IPV6)
> struct bridge_mcast_own_query ip6_own_query;
> + struct timer_list ip6_mc_router_timer;
> + struct hlist_node ip6_rlist;
> #endif /* IS_ENABLED(CONFIG_IPV6) */
> u32 multicast_eht_hosts_limit;
> u32 multicast_eht_hosts_cnt;
> @@ -457,6 +459,8 @@ struct net_bridge {
> struct bridge_mcast_querier ip4_querier;
> struct bridge_mcast_stats __percpu *mcast_stats;
> #if IS_ENABLED(CONFIG_IPV6)
> + struct hlist_head ip6_mc_router_list;
> + struct timer_list ip6_mc_router_timer;
> struct bridge_mcast_other_query ip6_other_query;
> struct bridge_mcast_own_query ip6_own_query;
> struct bridge_mcast_querier ip6_querier;
> @@ -872,7 +876,7 @@ static inline bool br_ip4_multicast_is_router(struct net_bridge *br)
> static inline bool br_ip6_multicast_is_router(struct net_bridge *br)
> {
> #if IS_ENABLED(CONFIG_IPV6)
> - return timer_pending(&br->ip4_mc_router_timer);
> + return timer_pending(&br->ip6_mc_router_timer);
> #else
> return false;
> #endif
>

2021-05-11 09:32:30

by Nikolay Aleksandrov

[permalink] [raw]
Subject: Re: [net-next v2 10/11] net: bridge: mcast: add ip4+ip6 mcast router timers to mdb netlink

On 09/05/2021 22:45, Linus Lüssing wrote:
> Now that we have split the multicast router state into two, one for IPv4
> and one for IPv6, also add individual timers to the mdb netlink router
> port dump. Leaving the old timer attribute for backwards compatibility.
>
> Signed-off-by: Linus Lüssing <[email protected]>
> ---
> include/uapi/linux/if_bridge.h | 2 ++
> net/bridge/br_mdb.c | 8 +++++++-
> 2 files changed, 9 insertions(+), 1 deletion(-)
>

Acked-by: Nikolay Aleksandrov <[email protected]>

> diff --git a/include/uapi/linux/if_bridge.h b/include/uapi/linux/if_bridge.h
> index 13d59c5..6b56a75 100644
> --- a/include/uapi/linux/if_bridge.h
> +++ b/include/uapi/linux/if_bridge.h
> @@ -627,6 +627,8 @@ enum {
> MDBA_ROUTER_PATTR_UNSPEC,
> MDBA_ROUTER_PATTR_TIMER,
> MDBA_ROUTER_PATTR_TYPE,
> + MDBA_ROUTER_PATTR_INET_TIMER,
> + MDBA_ROUTER_PATTR_INET6_TIMER,
> __MDBA_ROUTER_PATTR_MAX
> };
> #define MDBA_ROUTER_PATTR_MAX (__MDBA_ROUTER_PATTR_MAX - 1)
> diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
> index 3c608da..2cdd9b6 100644
> --- a/net/bridge/br_mdb.c
> +++ b/net/bridge/br_mdb.c
> @@ -79,7 +79,13 @@ static int br_rports_fill_info(struct sk_buff *skb, struct netlink_callback *cb,
> nla_put_u32(skb, MDBA_ROUTER_PATTR_TIMER,
> max(ip4_timer, ip6_timer)) ||
> nla_put_u8(skb, MDBA_ROUTER_PATTR_TYPE,
> - p->multicast_router)) {
> + p->multicast_router) ||
> + (have_ip4_mc_rtr &&
> + nla_put_u32(skb, MDBA_ROUTER_PATTR_INET_TIMER,
> + ip4_timer)) ||
> + (have_ip6_mc_rtr &&
> + nla_put_u32(skb, MDBA_ROUTER_PATTR_INET6_TIMER,
> + ip6_timer))) {
> nla_nest_cancel(skb, port_nest);
> goto fail;
> }
>

2021-05-11 09:34:48

by Nikolay Aleksandrov

[permalink] [raw]
Subject: Re: [net-next v2 09/11] net: bridge: mcast: split multicast router state for IPv4 and IPv6

On 11/05/2021 12:29, Nikolay Aleksandrov wrote:
> On 09/05/2021 22:45, Linus Lüssing wrote:
>> A multicast router for IPv4 does not imply that the same host also is a
>> multicast router for IPv6 and vice versa.
>>
>> To reduce multicast traffic when a host is only a multicast router for
>> one of these two protocol families, keep router state for IPv4 and IPv6
>> separately. Similar to how querier state is kept separately.
>>
>> For backwards compatibility for netlink and switchdev notifications
>> these two will still only notify if a port switched from either no
>> IPv4/IPv6 multicast router to any IPv4/IPv6 multicast router or the
>> other way round. However a full netlink MDB router dump will now also
>> include a multicast router timeout for both IPv4 and IPv6.
>>
>> Signed-off-by: Linus Lüssing <[email protected]>
>> ---
>> net/bridge/br_forward.c | 8 ++
>> net/bridge/br_mdb.c | 10 ++
>> net/bridge/br_multicast.c | 197 ++++++++++++++++++++++++++++++++++----
>> net/bridge/br_private.h | 6 +-
>> 4 files changed, 201 insertions(+), 20 deletions(-)
[snip]
>> +#else
>> +static inline void br_ip6_multicast_add_router(struct net_bridge *br,
>> + struct net_bridge_port *port)
>> +{
>> +}
>
> Actually that goes for multicast_add_router, too.
>

err, my bad - multicast_add_router is fine as is, sorry about that

> I'm saying all this because soon I'll be adding per-vlan multicast router support
> and these will be reusable there without any modification if they can take any list.
> Also it'll be easier to maintain one set of functions instead of multiple identical ones.
>

2021-05-11 11:30:59

by Linus Lüssing

[permalink] [raw]
Subject: Re: [net-next v2 09/11] net: bridge: mcast: split multicast router state for IPv4 and IPv6

On Tue, May 11, 2021 at 12:29:41PM +0300, Nikolay Aleksandrov wrote:
> [...]
> > -static void br_multicast_mark_router(struct net_bridge *br,
> > - struct net_bridge_port *port)
> > +#if IS_ENABLED(CONFIG_IPV6)
> > +struct hlist_node *
> > +br_ip6_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->ip6_mc_router_list, ip6_rlist) {
> > + if ((unsigned long)port >= (unsigned long)p)
> > + break;
> > + slot = &p->ip6_rlist;
> > + }
> > +
> > + return slot;
> > +}
>
> The ip4/ip6 get_rport_slot functions are identical, why not add a list pointer
> and use one function ?

Hi Nikolay,

Thanks for all the feedback and reviewing again! I'll
remove (most of) the inlines as the router list modifications are
not in the fast path.

For the get_rport_slot functions, maybe I'm missing a simple
solution. Note that "ip6_rlist" in hlist_for_each_entry() is not a
pointer but will be expanded by the macro. I currently don't see
how I could solve this with just one hlist_for_each_entry().

Regards, Linus