Commit bb69ae04 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

anycast: Some RCU conversions 



- dev_get_by_flags() changed to dev_get_by_flags_rcu()

- ipv6_sock_ac_join() dont touch dev & idev refcounts
- ipv6_sock_ac_drop() dont touch dev & idev refcounts
- ipv6_sock_ac_close() dont touch dev & idev refcounts
- ipv6_dev_ac_dec() dount touch idev refcount
- ipv6_chk_acast_addr() dont touch idev refcount

Signed-off-by: default avatarEric Dumazet <eric.dumazet@gmail.com>
CC: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 6e8b11b4

include/linux/netdevice.h

+2 −2
Original line number Diff line number Diff line
@@ -1271,7 +1271,7 @@ extern void dev_add_pack(struct packet_type *pt); 
extern void		dev_remove_pack(struct packet_type *pt);

extern void		__dev_remove_pack(struct packet_type *pt);



extern struct net_device	*dev_get_by_flags(struct net *net, unsigned short flags,

extern struct net_device	*dev_get_by_flags_rcu(struct net *net, unsigned short flags,

						      unsigned short mask);

extern struct net_device	*dev_get_by_name(struct net *net, const char *name);

extern struct net_device	*dev_get_by_name_rcu(struct net *net, const char *name);

net/core/dev.c

+5 −9
Original line number Diff line number Diff line
@@ -803,35 +803,31 @@ struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type) 
EXPORT_SYMBOL(dev_getfirstbyhwtype);



/**

 *	dev_get_by_flags - find any device with given flags

 *	dev_get_by_flags_rcu - find any device with given flags

 *	@net: the applicable net namespace

 *	@if_flags: IFF_* values

 *	@mask: bitmask of bits in if_flags to check

 *

 *	Search for any interface with the given flags. Returns NULL if a device

 *	is not found or a pointer to the device. The device returned has

 *	had a reference added and the pointer is safe until the user calls

 *	dev_put to indicate they have finished with it.

 *	is not found or a pointer to the device. Must be called inside

 *	rcu_read_lock(), and result refcount is unchanged.

 */



struct net_device *dev_get_by_flags(struct net *net, unsigned short if_flags,

struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags,

				    unsigned short mask)

{

	struct net_device *dev, *ret;



	ret = NULL;

	rcu_read_lock();

	for_each_netdev_rcu(net, dev) {

		if (((dev->flags ^ if_flags) & mask) == 0) {

			dev_hold(dev);

			ret = dev;

			break;

		}

	}

	rcu_read_unlock();

	return ret;

}

EXPORT_SYMBOL(dev_get_by_flags);

EXPORT_SYMBOL(dev_get_by_flags_rcu);



/**

 *	dev_valid_name - check if name is okay for network device

net/ipv6/anycast.c

+42 −48
Original line number Diff line number Diff line
@@ -77,41 +77,40 @@ int ipv6_sock_ac_join(struct sock *sk, int ifindex, struct in6_addr *addr) 
	pac->acl_next = NULL;

	ipv6_addr_copy(&pac->acl_addr, addr);



	rcu_read_lock();

	if (ifindex == 0) {

		struct rt6_info *rt;



		rt = rt6_lookup(net, addr, NULL, 0, 0);

		if (rt) {

			dev = rt->rt6i_dev;

			dev_hold(dev);

			dst_release(&rt->u.dst);

		} else if (ishost) {

			err = -EADDRNOTAVAIL;

			goto out_free_pac;

			goto error;

		} else {

			/* router, no matching interface: just pick one */



			dev = dev_get_by_flags(net, IFF_UP, IFF_UP|IFF_LOOPBACK);

			dev = dev_get_by_flags_rcu(net, IFF_UP,

						   IFF_UP | IFF_LOOPBACK);

		}

	} else

		dev = dev_get_by_index(net, ifindex);

		dev = dev_get_by_index_rcu(net, ifindex);



	if (dev == NULL) {

		err = -ENODEV;

		goto out_free_pac;

		goto error;

	}



	idev = in6_dev_get(dev);

	idev = __in6_dev_get(dev);

	if (!idev) {

		if (ifindex)

			err = -ENODEV;

		else

			err = -EADDRNOTAVAIL;

		goto out_dev_put;

		goto error;

	}

	/* reset ishost, now that we have a specific device */

	ishost = !idev->cnf.forwarding;

	in6_dev_put(idev);



	pac->acl_ifindex = dev->ifindex;
@@ -124,25 +123,21 @@ int ipv6_sock_ac_join(struct sock *sk, int ifindex, struct in6_addr *addr) 
		if (ishost)

			err = -EADDRNOTAVAIL;

		if (err)

			goto out_dev_put;

			goto error;

	}



	err = ipv6_dev_ac_inc(dev, addr);

	if (err)

		goto out_dev_put;



	if (!err) {

		write_lock_bh(&ipv6_sk_ac_lock);

		pac->acl_next = np->ipv6_ac_list;

		np->ipv6_ac_list = pac;

		write_unlock_bh(&ipv6_sk_ac_lock);

		pac = NULL;

	}



	dev_put(dev);



	return 0;



out_dev_put:

	dev_put(dev);

out_free_pac:

error:

	rcu_read_unlock();

	if (pac)

		sock_kfree_s(sk, pac, sizeof(*pac));

	return err;

}
@@ -176,11 +171,12 @@ int ipv6_sock_ac_drop(struct sock *sk, int ifindex, struct in6_addr *addr) 


	write_unlock_bh(&ipv6_sk_ac_lock);



	dev = dev_get_by_index(net, pac->acl_ifindex);

	if (dev) {

	rcu_read_lock();

	dev = dev_get_by_index_rcu(net, pac->acl_ifindex);

	if (dev)

		ipv6_dev_ac_dec(dev, &pac->acl_addr);

		dev_put(dev);

	}

	rcu_read_unlock();



	sock_kfree_s(sk, pac, sizeof(*pac));

	return 0;

}
@@ -199,13 +195,12 @@ void ipv6_sock_ac_close(struct sock *sk) 
	write_unlock_bh(&ipv6_sk_ac_lock);



	prev_index = 0;

	rcu_read_lock();

	while (pac) {

		struct ipv6_ac_socklist *next = pac->acl_next;



		if (pac->acl_ifindex != prev_index) {

			if (dev)

				dev_put(dev);

			dev = dev_get_by_index(net, pac->acl_ifindex);

			dev = dev_get_by_index_rcu(net, pac->acl_ifindex);

			prev_index = pac->acl_ifindex;

		}

		if (dev)
@@ -213,8 +208,7 @@ void ipv6_sock_ac_close(struct sock *sk) 
		sock_kfree_s(sk, pac, sizeof(*pac));

		pac = next;

	}

	if (dev)

		dev_put(dev);

	rcu_read_unlock();

}



#if 0
@@ -363,33 +357,32 @@ int __ipv6_dev_ac_dec(struct inet6_dev *idev, struct in6_addr *addr) 
	return 0;

}



/* called with rcu_read_lock() */

static int ipv6_dev_ac_dec(struct net_device *dev, struct in6_addr *addr)

{

	int ret;

	struct inet6_dev *idev = in6_dev_get(dev);

	struct inet6_dev *idev = __in6_dev_get(dev);



	if (idev == NULL)

		return -ENODEV;

	ret = __ipv6_dev_ac_dec(idev, addr);

	in6_dev_put(idev);

	return ret;

	return __ipv6_dev_ac_dec(idev, addr);

}



/*

 *	check if the interface has this anycast address

 *	called with rcu_read_lock()

 */

static int ipv6_chk_acast_dev(struct net_device *dev, struct in6_addr *addr)

{

	struct inet6_dev *idev;

	struct ifacaddr6 *aca;



	idev = in6_dev_get(dev);

	idev = __in6_dev_get(dev);

	if (idev) {

		read_lock_bh(&idev->lock);

		for (aca = idev->ac_list; aca; aca = aca->aca_next)

			if (ipv6_addr_equal(&aca->aca_addr, addr))

				break;

		read_unlock_bh(&idev->lock);

		in6_dev_put(idev);

		return aca != NULL;

	}

	return 0;
@@ -403,9 +396,10 @@ int ipv6_chk_acast_addr(struct net *net, struct net_device *dev, 
{

	int found = 0;



	if (dev)

		return ipv6_chk_acast_dev(dev, addr);

	rcu_read_lock();

	if (dev)

		found = ipv6_chk_acast_dev(dev, addr);

	else

		for_each_netdev_rcu(net, dev)

			if (ipv6_chk_acast_dev(dev, addr)) {

				found = 1;

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