netfilter: ecache: prepare for event notifier merge

This prepares for merge for ct and exp notifier structs.

The 'fcn' member is renamed to something unique.
Second, the register/unregister api is simplified.  There is only
one implementation so there is no need to do any error checking.

Replace the EBUSY logic with WARN_ON_ONCE.  This allows to remove
error unwinding.

The exp notifier register/unregister function is removed in
a followup patch.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2021-08-16 17:16:25 +02:00 committed by Pablo Neira Ayuso
parent b3afdc1758
commit b86c0e6429
3 changed files with 17 additions and 42 deletions

View File

@ -73,13 +73,12 @@ struct nf_ct_event {
};
struct nf_ct_event_notifier {
int (*fcn)(unsigned int events, const struct nf_ct_event *item);
int (*ct_event)(unsigned int events, const struct nf_ct_event *item);
};
int nf_conntrack_register_notifier(struct net *net,
struct nf_ct_event_notifier *nb);
void nf_conntrack_unregister_notifier(struct net *net,
struct nf_ct_event_notifier *nb);
void nf_conntrack_register_notifier(struct net *net,
const struct nf_ct_event_notifier *nb);
void nf_conntrack_unregister_notifier(struct net *net);
void nf_ct_deliver_cached_events(struct nf_conn *ct);
int nf_conntrack_eventmask_report(unsigned int eventmask, struct nf_conn *ct,
@ -159,7 +158,7 @@ struct nf_exp_event {
};
struct nf_exp_event_notifier {
int (*fcn)(unsigned int events, struct nf_exp_event *item);
int (*exp_event)(unsigned int events, struct nf_exp_event *item);
};
int nf_ct_expect_register_notifier(struct net *net,

View File

@ -151,7 +151,7 @@ static int __nf_conntrack_eventmask_report(struct nf_conntrack_ecache *e,
return 0;
}
ret = notify->fcn(events | missed, item);
ret = notify->ct_event(events | missed, item);
rcu_read_unlock();
if (likely(ret >= 0 && missed == 0))
@ -258,43 +258,29 @@ void nf_ct_expect_event_report(enum ip_conntrack_expect_events event,
.portid = portid,
.report = report
};
notify->fcn(1 << event, &item);
notify->exp_event(1 << event, &item);
}
out_unlock:
rcu_read_unlock();
}
int nf_conntrack_register_notifier(struct net *net,
struct nf_ct_event_notifier *new)
void nf_conntrack_register_notifier(struct net *net,
const struct nf_ct_event_notifier *new)
{
int ret;
struct nf_ct_event_notifier *notify;
mutex_lock(&nf_ct_ecache_mutex);
notify = rcu_dereference_protected(net->ct.nf_conntrack_event_cb,
lockdep_is_held(&nf_ct_ecache_mutex));
if (notify != NULL) {
ret = -EBUSY;
goto out_unlock;
}
WARN_ON_ONCE(notify);
rcu_assign_pointer(net->ct.nf_conntrack_event_cb, new);
ret = 0;
out_unlock:
mutex_unlock(&nf_ct_ecache_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(nf_conntrack_register_notifier);
void nf_conntrack_unregister_notifier(struct net *net,
struct nf_ct_event_notifier *new)
void nf_conntrack_unregister_notifier(struct net *net)
{
struct nf_ct_event_notifier *notify;
mutex_lock(&nf_ct_ecache_mutex);
notify = rcu_dereference_protected(net->ct.nf_conntrack_event_cb,
lockdep_is_held(&nf_ct_ecache_mutex));
BUG_ON(notify != new);
RCU_INIT_POINTER(net->ct.nf_conntrack_event_cb, NULL);
mutex_unlock(&nf_ct_ecache_mutex);
/* synchronize_rcu() is called from ctnetlink_exit. */

View File

@ -3755,11 +3755,11 @@ static int ctnetlink_stat_exp_cpu(struct sk_buff *skb,
#ifdef CONFIG_NF_CONNTRACK_EVENTS
static struct nf_ct_event_notifier ctnl_notifier = {
.fcn = ctnetlink_conntrack_event,
.ct_event = ctnetlink_conntrack_event,
};
static struct nf_exp_event_notifier ctnl_notifier_exp = {
.fcn = ctnetlink_expect_event,
.exp_event = ctnetlink_expect_event,
};
#endif
@ -3854,33 +3854,23 @@ static int __net_init ctnetlink_net_init(struct net *net)
#ifdef CONFIG_NF_CONNTRACK_EVENTS
int ret;
ret = nf_conntrack_register_notifier(net, &ctnl_notifier);
if (ret < 0) {
pr_err("ctnetlink_init: cannot register notifier.\n");
goto err_out;
}
nf_conntrack_register_notifier(net, &ctnl_notifier);
ret = nf_ct_expect_register_notifier(net, &ctnl_notifier_exp);
if (ret < 0) {
pr_err("ctnetlink_init: cannot expect register notifier.\n");
goto err_unreg_notifier;
nf_conntrack_unregister_notifier(net);
return ret;
}
#endif
return 0;
#ifdef CONFIG_NF_CONNTRACK_EVENTS
err_unreg_notifier:
nf_conntrack_unregister_notifier(net, &ctnl_notifier);
err_out:
return ret;
#endif
}
static void ctnetlink_net_exit(struct net *net)
{
#ifdef CONFIG_NF_CONNTRACK_EVENTS
nf_ct_expect_unregister_notifier(net, &ctnl_notifier_exp);
nf_conntrack_unregister_notifier(net, &ctnl_notifier);
nf_conntrack_unregister_notifier(net);
#endif
}