ip6mr: Move unregister_netdevice_many() out of ip6mr_free_table().

This is a prep commit to convert ip6mr_net_exit_batch() to
->exit_rtnl().

Let's move unregister_netdevice_many() in ip6mr_free_table()
to its callers.

Now ip6mr_rules_exit() can do batching all tables per netns.

Note that later we will remove RTNL and unregister_netdevice_many()
in ip6mr_rules_init().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260604224712.3209821-12-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 15 insertions, 8 deletions

diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index b5da94c9f074..f531c4a24ea1 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -85,7 +85,8 @@ static DEFINE_SPINLOCK(mfc_unres_lock);
 static struct kmem_cache *mrt_cachep __read_mostly;
 
 static struct mr_table *ip6mr_new_table(struct net *net, u32 id);
-static void ip6mr_free_table(struct mr_table *mrt);
+static void ip6mr_free_table(struct mr_table *mrt,
+			     struct list_head *dev_kill_list);
 
 static void ip6_mr_forward(struct net *net, struct mr_table *mrt,
 			   struct net_device *dev, struct sk_buff *skb,
@@ -228,6 +229,7 @@ static const struct fib_rules_ops __net_initconst ip6mr_rules_ops_template = {
 static int __net_init ip6mr_rules_init(struct net *net)
 {
 	struct fib_rules_ops *ops;
+	LIST_HEAD(dev_kill_list);
 	struct mr_table *mrt;
 	int err;
 
@@ -252,7 +254,8 @@ static int __net_init ip6mr_rules_init(struct net *net)
 
 err2:
 	rtnl_lock();
-	ip6mr_free_table(mrt);
+	ip6mr_free_table(mrt, &dev_kill_list);
+	unregister_netdevice_many(&dev_kill_list);
 	rtnl_unlock();
 err1:
 	fib_rules_unregister(ops);
@@ -267,12 +270,15 @@ static void __net_exit ip6mr_rules_exit(struct net *net)
 static void __net_exit ip6mr_rules_exit_rtnl(struct net *net)
 {
 	struct mr_table *mrt, *next;
+	LIST_HEAD(dev_kill_list);
 
 	ASSERT_RTNL();
 	list_for_each_entry_safe(mrt, next, &net->ipv6.mr6_tables, list) {
 		list_del_rcu(&mrt->list);
-		ip6mr_free_table(mrt);
+		ip6mr_free_table(mrt, &dev_kill_list);
 	}
+
+	unregister_netdevice_many(&dev_kill_list);
 }
 
 static int ip6mr_rules_dump(struct net *net, struct notifier_block *nb,
@@ -339,11 +345,13 @@ static void __net_exit ip6mr_rules_exit(struct net *net)
 static void __net_exit ip6mr_rules_exit_rtnl(struct net *net)
 {
 	struct mr_table *mrt = rcu_dereference_protected(net->ipv6.mrt6, 1);
+	LIST_HEAD(dev_kill_list);
 
 	ASSERT_RTNL();
 
 	RCU_INIT_POINTER(net->ipv6.mrt6, NULL);
-	ip6mr_free_table(mrt);
+	ip6mr_free_table(mrt, &dev_kill_list);
+	unregister_netdevice_many(&dev_kill_list);
 }
 
 static int ip6mr_rules_dump(struct net *net, struct notifier_block *nb,
@@ -418,18 +426,17 @@ static struct mr_table *ip6mr_new_table(struct net *net, u32 id)
 			      ipmr_expire_process, ip6mr_new_table_set);
 }
 
-static void ip6mr_free_table(struct mr_table *mrt)
+static void ip6mr_free_table(struct mr_table *mrt,
+			     struct list_head *dev_kill_list)
 {
 	struct net *net = read_pnet(&mrt->net);
-	LIST_HEAD(dev_kill_list);
 
 	WARN_ON_ONCE(!mr_can_free_table(net));
 
 	timer_shutdown_sync(&mrt->ipmr_expire_timer);
 	mroute_clean_tables(mrt, MRT6_FLUSH_MIFS | MRT6_FLUSH_MIFS_STATIC |
 			    MRT6_FLUSH_MFC | MRT6_FLUSH_MFC_STATIC,
-			    &dev_kill_list);
-	unregister_netdevice_many(&dev_kill_list);
+			    dev_kill_list);
 
 	mr_table_free(mrt);
 }