From: Ido Schimmel <ido...@mellanox.com>
When a route is deleted we potentially need to promote the next route in
the FIB alias list (e.g., with an higher metric). In case we find such a
route, a replace notification is emitted. Otherwise, a delete
notification for the deleted route.
Signed-off-by: Ido Schimmel <ido...@mellanox.com>
---
net/ipv4/fib_trie.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index e5896729dcb9..ba597dbe1cc5 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -1586,6 +1586,36 @@ static void fib_remove_alias(struct trie *t, struct
key_vector *tp,
node_pull_suffix(tp, fa->fa_slen);
}
+static void fib_notify_alias_delete(struct net *net, u32 key,
+ struct hlist_head *fah,
+ struct fib_alias *fa_to_delete,
+ struct netlink_ext_ack *extack)
+{
+ struct fib_alias *fa_next, *fa_to_notify;
+ u32 tb_id = fa_to_delete->tb_id;
+ u8 slen = fa_to_delete->fa_slen;
+ enum fib_event_type fib_event;
+
+ /* Do not notify if we do not care about the route. */
+ if (fib_find_first_alias(fah, slen, tb_id) != fa_to_delete)
+ return;
+
+ /* Determine if the route should be replaced by the next route in the
+ * list.
+ */
+ fa_next = hlist_entry_safe(fa_to_delete->fa_list.next,
+ struct fib_alias, fa_list);
+ if (fa_next && fa_next->fa_slen == slen && fa_next->tb_id == tb_id) {
+ fib_event = FIB_EVENT_ENTRY_REPLACE_TMP;
+ fa_to_notify = fa_next;
+ } else {
+ fib_event = FIB_EVENT_ENTRY_DEL_TMP;
+ fa_to_notify = fa_to_delete;
+ }
+ call_fib_entry_notifiers(net, fib_event, key, KEYLENGTH - slen,
+ fa_to_notify, extack);
+}
+
/* Caller must hold RTNL. */
int fib_table_delete(struct net *net, struct fib_table *tb,
struct fib_config *cfg, struct netlink_ext_ack *extack)
@@ -1639,6 +1669,7 @@ int fib_table_delete(struct net *net, struct fib_table
*tb,
if (!fa_to_delete)
return -ESRCH;
+ fib_notify_alias_delete(net, key, &l->leaf, fa_to_delete, extack);
call_fib_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, key, plen,
fa_to_delete, extack);
rtmsg_fib(RTM_DELROUTE, htonl(key), fa_to_delete, plen, tb->tb_id,
--
2.21.0
