ipv6: drop some rcu_read_lock in mcast

Similarly the code is already protected by rtnl lock.

Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 13 deletions

diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 27ca0b741ccc..4fb761d4002d 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -162,7 +162,6 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
         mc_lst->addr = *addr;
 
         rtnl_lock();
-        rcu_read_lock();
         if (ifindex == 0) {
                 struct rt6_info *rt;
                 rt = rt6_lookup(net, addr, NULL, 0, 0);
@@ -171,10 +170,9 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
                         ip6_rt_put(rt);
                 }
         } else
-                dev = dev_get_by_index_rcu(net, ifindex);
+                dev = __dev_get_by_index(net, ifindex);
 
         if (dev == NULL) {
-                rcu_read_unlock();
                 rtnl_unlock();
                 sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
                 return -ENODEV;
@@ -192,7 +190,6 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
         err = ipv6_dev_mc_inc(dev, addr);
 
         if (err) {
-                rcu_read_unlock();
                 rtnl_unlock();
                 sock_kfree_s(sk, mc_lst, sizeof(*mc_lst));
                 return err;
@@ -201,7 +198,6 @@ int ipv6_sock_mc_join(struct sock *sk, int ifindex, const struct in6_addr *addr)
         mc_lst->next = np->ipv6_mc_list;
         rcu_assign_pointer(np->ipv6_mc_list, mc_lst);
 
-        rcu_read_unlock();
         rtnl_unlock();
 
         return 0;
@@ -230,8 +226,7 @@ int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
 
                         *lnk = mc_lst->next;
 
-                        rcu_read_lock();
-                        dev = dev_get_by_index_rcu(net, mc_lst->ifindex);
+                        dev = __dev_get_by_index(net, mc_lst->ifindex);
                         if (dev != NULL) {
                                 struct inet6_dev *idev = __in6_dev_get(dev);
 
@@ -240,7 +235,6 @@ int ipv6_sock_mc_drop(struct sock *sk, int ifindex, const struct in6_addr *addr)
                                         __ipv6_dev_mc_dec(idev, &mc_lst->addr);
                         } else
                                 (void) ip6_mc_leave_src(sk, mc_lst, NULL);
-                        rcu_read_unlock();
                         rtnl_unlock();
 
                         atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
@@ -299,8 +293,7 @@ void ipv6_sock_mc_close(struct sock *sk)
 
                 np->ipv6_mc_list = mc_lst->next;
 
-                rcu_read_lock();
-                dev = dev_get_by_index_rcu(net, mc_lst->ifindex);
+                dev = __dev_get_by_index(net, mc_lst->ifindex);
                 if (dev) {
                         struct inet6_dev *idev = __in6_dev_get(dev);
 
@@ -309,7 +302,6 @@ void ipv6_sock_mc_close(struct sock *sk)
                                 __ipv6_dev_mc_dec(idev, &mc_lst->addr);
                 } else
                         (void) ip6_mc_leave_src(sk, mc_lst, NULL);
-                rcu_read_unlock();
 
                 atomic_sub(sizeof(*mc_lst), &sk->sk_omem_alloc);
                 kfree_rcu(mc_lst, rcu);
@@ -934,7 +926,7 @@ int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
         struct inet6_dev *idev;
         int err;
 
-        rcu_read_lock();
+        ASSERT_RTNL();
 
         idev = __in6_dev_get(dev);
         if (!idev)
@@ -942,7 +934,6 @@ int ipv6_dev_mc_dec(struct net_device *dev, const struct in6_addr *addr)
         else
                 err = __ipv6_dev_mc_dec(idev, addr);
 
-        rcu_read_unlock();
         return err;
 }