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: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index ef0e7d9..02a3b2c 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -72,7 +72,7 @@
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 @@
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 @@
}
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 @@
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);
diff --git a/net/decnet/dn_rules.c b/net/decnet/dn_rules.c
index 72495f2..7466c54 100644
--- a/net/decnet/dn_rules.c
+++ b/net/decnet/dn_rules.c
@@ -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 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 @@
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 @@
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 @@
.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();
}
diff --git a/net/ipv4/fib_rules.c b/net/ipv4/fib_rules.c
index 1239ed2..ca2d07b 100644
--- a/net/ipv4/fib_rules.c
+++ b/net/ipv4/fib_rules.c
@@ -301,13 +301,9 @@
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 @@
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);
}
diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c
index 3b38f49..b7aa7c6 100644
--- a/net/ipv6/fib6_rules.c
+++ b/net/ipv6/fib6_rules.c
@@ -264,16 +264,14 @@
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 @@
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 = {