Commit 1691c63e authored by WANG Cong's avatar WANG Cong Committed by David S. Miller
Browse files

ipv6: refactor ipv6_dev_mc_inc() 



Refactor out allocation and initialization and make
the refcount code more readable.

Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f7ed925c

net/ipv6/mcast.c

+49 −33
Original line number Diff line number Diff line
@@ -641,14 +641,6 @@ bool inet6_mc_check(struct sock *sk, const struct in6_addr *mc_addr, 
	return rv;

}



static void ma_put(struct ifmcaddr6 *mc)

{

	if (atomic_dec_and_test(&mc->mca_refcnt)) {

		in6_dev_put(mc->idev);

		kfree(mc);

	}

}



static void igmp6_group_added(struct ifmcaddr6 *mc)

{

	struct net_device *dev = mc->idev->dev;
@@ -814,6 +806,48 @@ static void mld_clear_delrec(struct inet6_dev *idev) 
	read_unlock_bh(&idev->lock);

}



static void mca_get(struct ifmcaddr6 *mc)

{

	atomic_inc(&mc->mca_refcnt);

}



static void ma_put(struct ifmcaddr6 *mc)

{

	if (atomic_dec_and_test(&mc->mca_refcnt)) {

		in6_dev_put(mc->idev);

		kfree(mc);

	}

}



static struct ifmcaddr6 *mca_alloc(struct inet6_dev *idev,

				   const struct in6_addr *addr)

{

	struct ifmcaddr6 *mc;



	mc = kzalloc(sizeof(*mc), GFP_ATOMIC);

	if (mc == NULL)

		return NULL;



	setup_timer(&mc->mca_timer, igmp6_timer_handler, (unsigned long)mc);



	mc->mca_addr = *addr;

	mc->idev = idev; /* reference taken by caller */

	mc->mca_users = 1;

	/* mca_stamp should be updated upon changes */

	mc->mca_cstamp = mc->mca_tstamp = jiffies;

	atomic_set(&mc->mca_refcnt, 1);

	spin_lock_init(&mc->mca_lock);



	/* initial mode is (EX, empty) */

	mc->mca_sfmode = MCAST_EXCLUDE;

	mc->mca_sfcount[MCAST_EXCLUDE] = 1;



	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||

	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)

		mc->mca_flags |= MAF_NOREPORT;



	return mc;

}



/*

 *	device multicast group inc (add if not found)
@@ -849,38 +883,20 @@ int ipv6_dev_mc_inc(struct net_device *dev, const struct in6_addr *addr) 
		}

	}



	/*

	 *	not found: create a new one.

	 */



	mc = kzalloc(sizeof(struct ifmcaddr6), GFP_ATOMIC);



	if (mc == NULL) {

	mc = mca_alloc(idev, addr);

	if (!mc) {

		write_unlock_bh(&idev->lock);

		in6_dev_put(idev);

		return -ENOMEM;

	}



	setup_timer(&mc->mca_timer, igmp6_timer_handler, (unsigned long)mc);



	mc->mca_addr = *addr;

	mc->idev = idev; /* (reference taken) */

	mc->mca_users = 1;

	/* mca_stamp should be updated upon changes */

	mc->mca_cstamp = mc->mca_tstamp = jiffies;

	atomic_set(&mc->mca_refcnt, 2);

	spin_lock_init(&mc->mca_lock);



	/* initial mode is (EX, empty) */

	mc->mca_sfmode = MCAST_EXCLUDE;

	mc->mca_sfcount[MCAST_EXCLUDE] = 1;



	if (ipv6_addr_is_ll_all_nodes(&mc->mca_addr) ||

	    IPV6_ADDR_MC_SCOPE(&mc->mca_addr) < IPV6_ADDR_SCOPE_LINKLOCAL)

		mc->mca_flags |= MAF_NOREPORT;



	mc->next = idev->mc_list;

	idev->mc_list = mc;



	/* Hold this for the code below before we unlock,

	 * it is already exposed via idev->mc_list.

	 */

	mca_get(mc);

	write_unlock_bh(&idev->lock);



	mld_del_delrec(idev, &mc->mca_addr);