[PATCH v8 net-next 06/12] net: bridge: enable bridge to send and receive blackhole FDB entries

From: Hans J. Schultz
Date: Wed Oct 19 2022 - 11:32:23 EST


Enable the bridge to receive blackhole FDB entries from drivers with
SWITCHDEV_FDB_ADD_TO_BRIDGE notifications and send them to drivers
with RTM_NEWNEIGH notifications.

Signed-off-by: Hans J. Schultz <netdev@xxxxxxxxxxxxxxxxxxxx>
---
include/net/switchdev.h | 1 +
net/bridge/br.c | 3 ++-
net/bridge/br_fdb.c | 19 ++++++++++++++++---
net/bridge/br_private.h | 3 ++-
net/bridge/br_switchdev.c | 1 +
5 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/include/net/switchdev.h b/include/net/switchdev.h
index ca0312b78294..39727902354e 100644
--- a/include/net/switchdev.h
+++ b/include/net/switchdev.h
@@ -249,6 +249,7 @@ struct switchdev_notifier_fdb_info {
u8 added_by_user:1,
is_local:1,
locked:1,
+ blackhole:1,
offloaded:1;
};

diff --git a/net/bridge/br.c b/net/bridge/br.c
index e0e2df2fa278..85fc529b6a9f 100644
--- a/net/bridge/br.c
+++ b/net/bridge/br.c
@@ -166,7 +166,8 @@ static int br_switchdev_event(struct notifier_block *unused,
case SWITCHDEV_FDB_ADD_TO_BRIDGE:
fdb_info = ptr;
err = br_fdb_external_learn_add(br, p, fdb_info->addr, fdb_info->vid,
- fdb_info->locked, false);
+ fdb_info->locked, fdb_info->is_local,
+ fdb_info->blackhole, false);
if (err) {
err = notifier_from_errno(err);
break;
diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index 8d207b1416f7..ef973d21d7bd 100644
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -1145,7 +1145,7 @@ static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
"FDB entry towards bridge must be permanent");
return -EINVAL;
}
- err = br_fdb_external_learn_add(br, p, addr, vid, false, true);
+ err = br_fdb_external_learn_add(br, p, addr, vid, false, false, false, true);
} else {
spin_lock_bh(&br->hash_lock);
err = fdb_add_entry(br, p, addr, ndm, nlh_flags, vid, ext_flags, nfea_tb);
@@ -1401,7 +1401,7 @@ void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)

int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
const unsigned char *addr, u16 vid, bool locked,
- bool swdev_notify)
+ bool local, bool blackhole, bool swdev_notify)
{
struct net_bridge_fdb_entry *fdb;
bool modified = false;
@@ -1418,12 +1418,15 @@ int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
if (swdev_notify)
flags |= BIT(BR_FDB_ADDED_BY_USER);

- if (!p)
+ if (!p || local)
flags |= BIT(BR_FDB_LOCAL);

if (locked)
flags |= BIT(BR_FDB_LOCKED);

+ if (blackhole)
+ flags |= BIT(BR_FDB_BLACKHOLE);
+
fdb = fdb_create(br, p, addr, vid, flags);
if (!fdb) {
err = -ENOMEM;
@@ -1447,11 +1450,21 @@ int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
modified = true;
}

+ if (local != test_bit(BR_FDB_LOCAL, &fdb->flags)) {
+ change_bit(BR_FDB_LOCAL, &fdb->flags);
+ modified = true;
+ }
+
if (locked != test_bit(BR_FDB_LOCKED, &fdb->flags)) {
change_bit(BR_FDB_LOCKED, &fdb->flags);
modified = true;
}

+ if (blackhole != test_bit(BR_FDB_BLACKHOLE, &fdb->flags)) {
+ change_bit(BR_FDB_BLACKHOLE, &fdb->flags);
+ modified = true;
+ }
+
if (swdev_notify)
set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);

diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 3e9f4d1fbd60..4202c80e465e 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -812,7 +812,8 @@ int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p);
void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p);
int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
const unsigned char *addr, u16 vid,
- bool locked, bool swdev_notify);
+ bool locked, bool local, bool blackhole,
+ bool swdev_notify);
int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
const unsigned char *addr, u16 vid,
bool swdev_notify);
diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
index ccf1b4cffdd0..ce7b80c782ec 100644
--- a/net/bridge/br_switchdev.c
+++ b/net/bridge/br_switchdev.c
@@ -137,6 +137,7 @@ static void br_switchdev_fdb_populate(struct net_bridge *br,
item->offloaded = test_bit(BR_FDB_OFFLOADED, &fdb->flags);
item->is_local = test_bit(BR_FDB_LOCAL, &fdb->flags);
item->locked = test_bit(BR_FDB_LOCKED, &fdb->flags);
+ item->blackhole = test_bit(BR_FDB_BLACKHOLE, &fdb->flags);
item->info.dev = (!p || item->is_local) ? br->dev : p->dev;
item->info.ctx = ctx;
}
--
2.34.1