Commit e9c5158a authored by Eric W. Biederman's avatar Eric W. Biederman Committed by David S. Miller
Browse files

net: Allow fib_rule_unregister to batch 



Refactor the code so fib_rules_register always takes a template instead
of the actual fib_rules_ops structure that will be used.  This is
required for network namespace support so 2 out of the 3 callers already
do this, it allows the error handling to be made common, and it allows
fib_rules_unregister to free the template for hte caller.

Modify fib_rules_unregister to use call_rcu instead of syncrhonize_rcu
to allw multiple namespaces to be cleaned up in the same rcu grace
period.

Signed-off-by: default avatarEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 3a765eda

include/net/fib_rules.h

+2 −1
Original line number Diff line number Diff line
@@ -66,6 +66,7 @@ struct fib_rules_ops { 
	struct list_head	rules_list;

	struct module		*owner;

	struct net		*fro_net;

	struct rcu_head		rcu;

};



#define FRA_GENERIC_POLICY \
@@ -102,7 +103,7 @@ static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla) 
	return frh->table;

}



extern int fib_rules_register(struct fib_rules_ops *);

extern struct fib_rules_ops *fib_rules_register(struct fib_rules_ops *, struct net *);

extern void fib_rules_unregister(struct fib_rules_ops *);

extern void                     fib_rules_cleanup_ops(struct fib_rules_ops *);

net/core/fib_rules.c

+33 −3
Original line number Diff line number Diff line
@@ -72,7 +72,7 @@ static void flush_route_cache(struct fib_rules_ops *ops) 
		ops->flush_cache(ops);

}



int fib_rules_register(struct fib_rules_ops *ops)

static int __fib_rules_register(struct fib_rules_ops *ops)

{

	int err = -EEXIST;

	struct fib_rules_ops *o;
@@ -102,6 +102,28 @@ errout: 
	return err;

}



struct fib_rules_ops *

fib_rules_register(struct fib_rules_ops *tmpl, struct net *net)

{

	struct fib_rules_ops *ops;

	int err;



	ops = kmemdup(tmpl, sizeof (*ops), GFP_KERNEL);

	if (ops == NULL)

		return ERR_PTR(-ENOMEM);



	INIT_LIST_HEAD(&ops->rules_list);

	ops->fro_net = net;



	err = __fib_rules_register(ops);

	if (err) {

		kfree(ops);

		ops = ERR_PTR(err);

	}



	return ops;

}



EXPORT_SYMBOL_GPL(fib_rules_register);



void fib_rules_cleanup_ops(struct fib_rules_ops *ops)
@@ -115,6 +137,15 @@ void fib_rules_cleanup_ops(struct fib_rules_ops *ops) 
}

EXPORT_SYMBOL_GPL(fib_rules_cleanup_ops);



static void fib_rules_put_rcu(struct rcu_head *head)

{

	struct fib_rules_ops *ops = container_of(head, struct fib_rules_ops, rcu);

	struct net *net = ops->fro_net;



	release_net(net);

	kfree(ops);

}



void fib_rules_unregister(struct fib_rules_ops *ops)

{

	struct net *net = ops->fro_net;
@@ -124,8 +155,7 @@ void fib_rules_unregister(struct fib_rules_ops *ops) 
	fib_rules_cleanup_ops(ops);

	spin_unlock(&net->rules_mod_lock);



	synchronize_rcu();

	release_net(net);

	call_rcu(&ops->rcu, fib_rules_put_rcu);

}



EXPORT_SYMBOL_GPL(fib_rules_unregister);

net/decnet/dn_rules.c

+12 −10
Original line number Diff line number Diff line
@@ -33,7 +33,7 @@ 
#include <net/dn_dev.h>

#include <net/dn_route.h>



static struct fib_rules_ops dn_fib_rules_ops;

static struct fib_rules_ops *dn_fib_rules_ops;



struct dn_fib_rule

{
@@ -56,7 +56,7 @@ int dn_fib_lookup(struct flowi *flp, struct dn_fib_res *res) 
	};

	int err;



	err = fib_rules_lookup(&dn_fib_rules_ops, flp, 0, &arg);

	err = fib_rules_lookup(dn_fib_rules_ops, flp, 0, &arg);

	res->r = arg.rule;



	return err;
@@ -217,9 +217,9 @@ static u32 dn_fib_rule_default_pref(struct fib_rules_ops *ops) 
	struct list_head *pos;

	struct fib_rule *rule;



	if (!list_empty(&dn_fib_rules_ops.rules_list)) {

		pos = dn_fib_rules_ops.rules_list.next;

		if (pos->next != &dn_fib_rules_ops.rules_list) {

	if (!list_empty(&dn_fib_rules_ops->rules_list)) {

		pos = dn_fib_rules_ops->rules_list.next;

		if (pos->next != &dn_fib_rules_ops->rules_list) {

			rule = list_entry(pos->next, struct fib_rule, list);

			if (rule->pref)

				return rule->pref - 1;
@@ -234,7 +234,7 @@ static void dn_fib_rule_flush_cache(struct fib_rules_ops *ops) 
	dn_rt_cache_flush(-1);

}



static struct fib_rules_ops dn_fib_rules_ops = {

static struct fib_rules_ops dn_fib_rules_ops_template = {

	.family		= AF_DECnet,

	.rule_size	= sizeof(struct dn_fib_rule),

	.addr_size	= sizeof(u16),
@@ -247,21 +247,23 @@ static struct fib_rules_ops dn_fib_rules_ops = { 
	.flush_cache	= dn_fib_rule_flush_cache,

	.nlgroup	= RTNLGRP_DECnet_RULE,

	.policy		= dn_fib_rule_policy,

	.rules_list	= LIST_HEAD_INIT(dn_fib_rules_ops.rules_list),

	.owner		= THIS_MODULE,

	.fro_net	= &init_net,

};



void __init dn_fib_rules_init(void)

{

	BUG_ON(fib_default_rule_add(&dn_fib_rules_ops, 0x7fff,

	dn_fib_rules_ops =

		fib_rules_register(&dn_fib_rules_ops_template, &init_net);

	BUG_ON(IS_ERR(dn_fib_rules_ops));

	BUG_ON(fib_default_rule_add(dn_fib_rules_ops, 0x7fff,

			            RT_TABLE_MAIN, 0));

	fib_rules_register(&dn_fib_rules_ops);

}



void __exit dn_fib_rules_cleanup(void)

{

	fib_rules_unregister(&dn_fib_rules_ops);

	fib_rules_unregister(dn_fib_rules_ops);

	rcu_barrier();

}

net/ipv4/fib_rules.c

+3 −9
Original line number Diff line number Diff line
@@ -301,13 +301,9 @@ int __net_init fib4_rules_init(struct net *net) 
	int err;

	struct fib_rules_ops *ops;



	ops = kmemdup(&fib4_rules_ops_template, sizeof(*ops), GFP_KERNEL);

	if (ops == NULL)

		return -ENOMEM;

	INIT_LIST_HEAD(&ops->rules_list);

	ops->fro_net = net;



	fib_rules_register(ops);

	ops = fib_rules_register(&fib4_rules_ops_template, net);

	if (IS_ERR(ops))

		return PTR_ERR(ops);



	err = fib_default_rules_init(ops);

	if (err < 0)
@@ -318,12 +314,10 @@ int __net_init fib4_rules_init(struct net *net) 
fail:

	/* also cleans all rules already added */

	fib_rules_unregister(ops);

	kfree(ops);

	return err;

}



void __net_exit fib4_rules_exit(struct net *net)

{

	fib_rules_unregister(net->ipv4.rules_ops);

	kfree(net->ipv4.rules_ops);

}

net/ipv6/fib6_rules.c

+7 −15
Original line number Diff line number Diff line
@@ -264,16 +264,14 @@ static struct fib_rules_ops fib6_rules_ops_template = { 


static int fib6_rules_net_init(struct net *net)

{

	struct fib_rules_ops *ops;

	int err = -ENOMEM;



	net->ipv6.fib6_rules_ops = kmemdup(&fib6_rules_ops_template,

					   sizeof(*net->ipv6.fib6_rules_ops),

					   GFP_KERNEL);

	if (!net->ipv6.fib6_rules_ops)

		goto out;

	ops = fib_rules_register(&fib6_rules_ops_template, net);

	if (IS_ERR(ops))

		return PTR_ERR(ops);

	net->ipv6.fib6_rules_ops = ops;



	net->ipv6.fib6_rules_ops->fro_net = net;

	INIT_LIST_HEAD(&net->ipv6.fib6_rules_ops->rules_list);



	err = fib_default_rule_add(net->ipv6.fib6_rules_ops, 0,

				   RT6_TABLE_LOCAL, 0);
@@ -283,25 +281,19 @@ static int fib6_rules_net_init(struct net *net) 
	err = fib_default_rule_add(net->ipv6.fib6_rules_ops,

				   0x7FFE, RT6_TABLE_MAIN, 0);

	if (err)

		goto out_fib6_default_rule_add;

		goto out_fib6_rules_ops;



	err = fib_rules_register(net->ipv6.fib6_rules_ops);

	if (err)

		goto out_fib6_default_rule_add;

out:

	return err;



out_fib6_default_rule_add:

	fib_rules_cleanup_ops(net->ipv6.fib6_rules_ops);

out_fib6_rules_ops:

	kfree(net->ipv6.fib6_rules_ops);

	fib_rules_unregister(ops);

	goto out;

}



static void fib6_rules_net_exit(struct net *net)

{

	fib_rules_unregister(net->ipv6.fib6_rules_ops);

	kfree(net->ipv6.fib6_rules_ops);

}



static struct pernet_operations fib6_rules_net_ops = {

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