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>

diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index 9aa499a..7f12c28 100644 (file)
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -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);