ipv6: refactor __ipv6_dev_ac_inc()
Refactor out allocation and initialization and make
the refcount code more readable.
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/anycast.c b/net/ipv6/anycast.c
index 66c1932..952c1fd 100644
--- a/net/ipv6/anycast.c
+++ b/net/ipv6/anycast.c
@@ -203,6 +203,11 @@
rtnl_unlock();
}
+static void aca_get(struct ifacaddr6 *aca)
+{
+ atomic_inc(&aca->aca_refcnt);
+}
+
static void aca_put(struct ifacaddr6 *ac)
{
if (atomic_dec_and_test(&ac->aca_refcnt)) {
@@ -212,6 +217,29 @@
}
}
+static struct ifacaddr6 *aca_alloc(struct rt6_info *rt,
+ const struct in6_addr *addr)
+{
+ struct inet6_dev *idev = rt->rt6i_idev;
+ struct ifacaddr6 *aca;
+
+ aca = kzalloc(sizeof(*aca), GFP_ATOMIC);
+ if (aca == NULL)
+ return NULL;
+
+ aca->aca_addr = *addr;
+ in6_dev_hold(idev);
+ aca->aca_idev = idev;
+ aca->aca_rt = rt;
+ aca->aca_users = 1;
+ /* aca_tstamp should be updated upon changes */
+ aca->aca_cstamp = aca->aca_tstamp = jiffies;
+ atomic_set(&aca->aca_refcnt, 1);
+ spin_lock_init(&aca->aca_lock);
+
+ return aca;
+}
+
/*
* device anycast group inc (add if not found)
*/
@@ -223,7 +251,6 @@
ASSERT_RTNL();
- in6_dev_hold(idev);
write_lock_bh(&idev->lock);
if (idev->dead) {
err = -ENODEV;
@@ -238,35 +265,25 @@
}
}
- /*
- * not found: create a new one.
- */
-
- aca = kzalloc(sizeof(struct ifacaddr6), GFP_ATOMIC);
-
+ rt = addrconf_dst_alloc(idev, addr, true);
+ if (IS_ERR(rt)) {
+ err = PTR_ERR(rt);
+ goto out;
+ }
+ aca = aca_alloc(rt, addr);
if (aca == NULL) {
+ ip6_rt_put(rt);
err = -ENOMEM;
goto out;
}
- rt = addrconf_dst_alloc(idev, addr, true);
- if (IS_ERR(rt)) {
- kfree(aca);
- err = PTR_ERR(rt);
- goto out;
- }
-
- aca->aca_addr = *addr;
- aca->aca_idev = idev;
- aca->aca_rt = rt;
- aca->aca_users = 1;
- /* aca_tstamp should be updated upon changes */
- aca->aca_cstamp = aca->aca_tstamp = jiffies;
- atomic_set(&aca->aca_refcnt, 2);
- spin_lock_init(&aca->aca_lock);
-
aca->aca_next = idev->ac_list;
idev->ac_list = aca;
+
+ /* Hold this for addrconf_join_solict() below before we unlock,
+ * it is already exposed via idev->ac_list.
+ */
+ aca_get(aca);
write_unlock_bh(&idev->lock);
ip6_ins_rt(rt);
@@ -277,7 +294,6 @@
return 0;
out:
write_unlock_bh(&idev->lock);
- in6_dev_put(idev);
return err;
}