net: fib_rules: Implement notification logic in core

Unlike the routing tables, the FIB rules share a common core, so instead
of replicating the same logic for each address family we can simply dump
the rules and send notifications from the core itself.

To protect the integrity of the dump, a rules-specific sequence counter
is added for each address family and incremented whenever a rule is
added or deleted (under RTNL).

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 35 deletions

diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c
index acdbf5a..35d646a 100644
--- a/net/ipv4/fib_rules.c
+++ b/net/ipv4/fib_rules.c
@@ -32,7 +32,6 @@
 #include <net/tcp.h>
 #include <net/ip_fib.h>
 #include <net/fib_rules.h>
-#include <net/fib_notifier.h>
 
 struct fib4_rule {
 	struct fib_rule		common;
@@ -69,6 +68,16 @@ bool fib4_rule_default(const struct fib_rule *rule)
 }
 EXPORT_SYMBOL_GPL(fib4_rule_default);
 
+int fib4_rules_dump(struct net *net, struct notifier_block *nb)
+{
+	return fib_rules_dump(net, nb, AF_INET);
+}
+
+unsigned int fib4_rules_seq_read(struct net *net)
+{
+	return fib_rules_seq_read(net, AF_INET);
+}
+
 int __fib_lookup(struct net *net, struct flowi4 *flp,
 		 struct fib_result *res, unsigned int flags)
 {
@@ -186,38 +195,6 @@ static struct fib_table *fib_empty_table(struct net *net)
 	return NULL;
 }
 
-static int call_fib_rule_notifier(struct notifier_block *nb, struct net *net,
-				  enum fib_event_type event_type,
-				  struct fib_rule *rule)
-{
-	struct fib_rule_notifier_info info = {
-		.rule = rule,
-	};
-
-	return call_fib4_notifier(nb, net, event_type, &info.info);
-}
-
-static int call_fib_rule_notifiers(struct net *net,
-				   enum fib_event_type event_type,
-				   struct fib_rule *rule)
-{
-	struct fib_rule_notifier_info info = {
-		.rule = rule,
-	};
-
-	return call_fib4_notifiers(net, event_type, &info.info);
-}
-
-/* Called with rcu_read_lock() */
-void fib_rules_notify(struct net *net, struct notifier_block *nb)
-{
-	struct fib_rules_ops *ops = net->ipv4.rules_ops;
-	struct fib_rule *rule;
-
-	list_for_each_entry_rcu(rule, &ops->rules_list, list)
-		call_fib_rule_notifier(nb, net, FIB_EVENT_RULE_ADD, rule);
-}
-
 static const struct nla_policy fib4_rule_policy[FRA_MAX+1] = {
 	FRA_GENERIC_POLICY,
 	[FRA_FLOW]	= { .type = NLA_U32 },
@@ -274,7 +251,6 @@ static int fib4_rule_configure(struct fib_rule *rule, struct sk_buff *skb,
 	rule4->tos = frh->tos;
 
 	net->ipv4.fib_has_custom_rules = true;
-	call_fib_rule_notifiers(net, FIB_EVENT_RULE_ADD, rule);
 
 	err = 0;
 errout:
@@ -296,7 +272,6 @@ static int fib4_rule_delete(struct fib_rule *rule)
 		net->ipv4.fib_num_tclassid_users--;
 #endif
 	net->ipv4.fib_has_custom_rules = true;
-	call_fib_rule_notifiers(net, FIB_EVENT_RULE_DEL, rule);
 errout:
 	return err;
 }