lockd: introduce lockd_put()

There is some cleanup that is duplicated in lockd_down() and the failure
path of lockd_up().
Factor these out into a new lockd_put() and call it from both places.

lockd_put() does *not* take the mutex - that must be held by the caller.
It decrements nlmsvc_users and if that reaches zero, it cleans up.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This commit is contained in:
NeilBrown 2021-11-29 15:51:25 +11:00 committed by Chuck Lever
parent 6a4e2527a6
commit 865b674069

View file

@ -351,14 +351,6 @@ static struct notifier_block lockd_inet6addr_notifier = {
};
#endif
static void lockd_unregister_notifiers(void)
{
unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
#if IS_ENABLED(CONFIG_IPV6)
unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
#endif
}
static int lockd_start_svc(struct svc_serv *serv)
{
int error;
@ -450,6 +442,27 @@ static int lockd_create_svc(void)
return 0;
}
static void lockd_put(void)
{
if (WARN(nlmsvc_users <= 0, "lockd_down: no users!\n"))
return;
if (--nlmsvc_users)
return;
unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
#if IS_ENABLED(CONFIG_IPV6)
unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
#endif
if (nlmsvc_task) {
kthread_stop(nlmsvc_task);
dprintk("lockd_down: service stopped\n");
nlmsvc_task = NULL;
}
nlmsvc_serv = NULL;
dprintk("lockd_down: service destroyed\n");
}
/*
* Bring up the lockd process if it's not already up.
*/
@ -461,21 +474,16 @@ int lockd_up(struct net *net, const struct cred *cred)
error = lockd_create_svc();
if (error)
goto err_create;
goto err;
nlmsvc_users++;
error = lockd_up_net(nlmsvc_serv, net, cred);
if (error < 0) {
goto err_put;
lockd_put();
goto err;
}
nlmsvc_users++;
err_put:
if (nlmsvc_users == 0) {
lockd_unregister_notifiers();
kthread_stop(nlmsvc_task);
nlmsvc_serv = NULL;
}
err_create:
err:
mutex_unlock(&nlmsvc_mutex);
return error;
}
@ -489,25 +497,7 @@ lockd_down(struct net *net)
{
mutex_lock(&nlmsvc_mutex);
lockd_down_net(nlmsvc_serv, net);
if (nlmsvc_users) {
if (--nlmsvc_users)
goto out;
} else {
printk(KERN_ERR "lockd_down: no users! task=%p\n",
nlmsvc_task);
BUG();
}
if (!nlmsvc_task) {
printk(KERN_ERR "lockd_down: no lockd running.\n");
BUG();
}
lockd_unregister_notifiers();
kthread_stop(nlmsvc_task);
dprintk("lockd_down: service destroyed\n");
nlmsvc_serv = NULL;
nlmsvc_task = NULL;
out:
lockd_put();
mutex_unlock(&nlmsvc_mutex);
}
EXPORT_SYMBOL_GPL(lockd_down);