ipv6: Replace inet6_ifaddr->dead with state

This patch replaces the boolean dead flag on inet6_ifaddr with
a state enum.  This allows us to roll back changes when deleting
an address according to whether DAD has completed or not.

This patch only adds the state field and does not change the logic.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/if_inet6.h b/include/net/if_inet6.h
index 13f9fc0..f95ff8d 100644 (file)
--- a/include/net/if_inet6.h
+++ b/include/net/if_inet6.h
@@ -32,6 +32,13 @@
 
 #ifdef __KERNEL__
 
+enum {
+       INET6_IFADDR_STATE_DAD,
+       INET6_IFADDR_STATE_POSTDAD,
+       INET6_IFADDR_STATE_UP,
+       INET6_IFADDR_STATE_DEAD,
+};
+
 struct inet6_ifaddr {
        struct in6_addr         addr;
        __u32                   prefix_len;
@@ -40,6 +47,9 @@ struct inet6_ifaddr {
        __u32                   prefered_lft;
        atomic_t                refcnt;
        spinlock_t              lock;
+       spinlock_t              state_lock;
+
+       int                     state;
 
        __u8                    probes;
        __u8                    flags;
@@ -62,8 +72,6 @@ struct inet6_ifaddr {
        struct inet6_ifaddr     *ifpub;
        int                     regen_count;
 #endif
-
-       int                     dead;
        struct rcu_head         rcu;
 };
 

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 75d3b8c..4e5ad9d 100644 (file)
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -553,7 +553,7 @@ void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
        if (del_timer(&ifp->timer))
                pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
 
-       if (!ifp->dead) {
+       if (ifp->state != INET6_IFADDR_STATE_DEAD) {
                pr_warning("Freeing alive inet6 address %p\n", ifp);
                return;
        }
@@ -648,6 +648,7 @@ ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
        ipv6_addr_copy(&ifa->addr, addr);
 
        spin_lock_init(&ifa->lock);
+       spin_lock_init(&ifa->state_lock);
        init_timer(&ifa->timer);
        INIT_HLIST_NODE(&ifa->addr_lst);
        ifa->timer.data = (unsigned long) ifa;
@@ -720,7 +721,7 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp)
 
        hash = ipv6_addr_hash(&ifp->addr);
 
-       ifp->dead = 1;
+       ifp->state = INET6_IFADDR_STATE_DEAD;
 
        spin_lock_bh(&addrconf_hash_lock);
        hlist_del_init_rcu(&ifp->addr_lst);
@@ -2665,7 +2666,7 @@ static int addrconf_ifdown(struct net_device *dev, int how)
                ifa = list_first_entry(&idev->tempaddr_list,
                                       struct inet6_ifaddr, tmp_list);
                list_del(&ifa->tmp_list);
-               ifa->dead = 1;
+               ifa->state = INET6_IFADDR_STATE_DEAD;
                write_unlock_bh(&idev->lock);
                spin_lock_bh(&ifa->lock);
 
@@ -2707,7 +2708,7 @@ static int addrconf_ifdown(struct net_device *dev, int how)
                        write_unlock_bh(&idev->lock);
                } else {
                        list_del(&ifa->if_list);
-                       ifa->dead = 1;
+                       ifa->state = INET6_IFADDR_STATE_DEAD;
                        write_unlock_bh(&idev->lock);
 
                        /* clear hash table */
@@ -2717,7 +2718,7 @@ static int addrconf_ifdown(struct net_device *dev, int how)
                }
 
                __ipv6_ifa_notify(RTM_DELADDR, ifa);
-               if (ifa->dead)
+               if (ifa->state == INET6_IFADDR_STATE_DEAD)
                        atomic_notifier_call_chain(&inet6addr_chain,
                                                   NETDEV_DOWN, ifa);
                in6_ifa_put(ifa);
@@ -2815,7 +2816,7 @@ static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags)
        net_srandom(ifp->addr.s6_addr32[3]);
 
        read_lock_bh(&idev->lock);
-       if (ifp->dead)
+       if (ifp->state == INET6_IFADDR_STATE_DEAD)
                goto out;
 
        spin_lock(&ifp->lock);
@@ -4050,7 +4051,8 @@ static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
                addrconf_leave_solict(ifp->idev, &ifp->addr);
                dst_hold(&ifp->rt->u.dst);
 
-               if (ifp->dead && ip6_del_rt(ifp->rt))
+               if (ifp->state == INET6_IFADDR_STATE_DEAD &&
+                   ip6_del_rt(ifp->rt))
                        dst_free(&ifp->rt->u.dst);
                break;
        }