net/ipv6: Remove aca_idev

aca_idev has only 1 user - inet6_fill_ifacaddr - and it only
wants the device index which can be extracted from the fib6_info
nexthop.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/if_inet6.h

@@ -143,7 +143,6 @@ struct ipv6_ac_socklist {
 
 struct ifacaddr6 {
 	struct in6_addr		aca_addr;
-	struct inet6_dev	*aca_idev;
 	struct fib6_info	*aca_rt;
 	struct ifacaddr6	*aca_next;
 	int			aca_users;

include/net/ip6_fib.h

@@ -410,6 +410,11 @@ int fib6_add(struct fib6_node *root, struct fib6_info *rt,
 	     struct nl_info *info, struct netlink_ext_ack *extack);
 int fib6_del(struct fib6_info *rt, struct nl_info *info);
 
+static inline struct net_device *fib6_info_nh_dev(const struct fib6_info *f6i)
+{
+	return f6i->fib6_nh.nh_dev;
+}
+
 void inet6_rt_notify(int event, struct fib6_info *rt, struct nl_info *info,
 		     unsigned int flags);
 

net/ipv6/addrconf.c

@@ -4817,9 +4817,10 @@ static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
 				u32 portid, u32 seq, int event, unsigned int flags)
 {
+	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
+	int ifindex = dev ? dev->ifindex : 1;
 	struct nlmsghdr  *nlh;
 	u8 scope = RT_SCOPE_UNIVERSE;
-	int ifindex = ifaca->aca_idev->dev->ifindex;
 
 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
 		scope = RT_SCOPE_SITE;

net/ipv6/anycast.c

@@ -212,7 +212,6 @@ static void aca_get(struct ifacaddr6 *aca)
 static void aca_put(struct ifacaddr6 *ac)
 {
 	if (refcount_dec_and_test(&ac->aca_refcnt)) {
-		in6_dev_put(ac->aca_idev);
 		fib6_info_release(ac->aca_rt);
 		kfree(ac);
 	}
@@ -221,16 +220,13 @@ static void aca_put(struct ifacaddr6 *ac)
 static struct ifacaddr6 *aca_alloc(struct fib6_info *f6i,
 				   const struct in6_addr *addr)
 {
-	struct inet6_dev *idev = f6i->fib6_idev;
 	struct ifacaddr6 *aca;
 
 	aca = kzalloc(sizeof(*aca), GFP_ATOMIC);
 	if (!aca)
 		return NULL;
 
 	aca->aca_addr = *addr;
-	in6_dev_hold(idev);
-	aca->aca_idev = idev;
 	fib6_info_hold(f6i);
 	aca->aca_rt = f6i;
 	aca->aca_users = 1;