[PATCH 05/11] lockd: Add /sys/fs/lockd/mon

[Chuck Lever <chuck.lever@oracle.com>]

Add parent directory to contain entries representing each entry in
lockd's nsm_handles cache.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---

 fs/lockd/mon.c              |   27 +++++++++++++++++++++++++++
 fs/lockd/svc.c              |    8 ++++++++
 include/linux/lockd/lockd.h |    2 ++
 3 files changed, 37 insertions(+), 0 deletions(-)

diff --git a/fs/lockd/mon.c b/fs/lockd/mon.c
index f956651..77e4927 100644
--- a/fs/lockd/mon.c
+++ b/fs/lockd/mon.c
@@ -56,6 +56,8 @@ static				DEFINE_SPINLOCK(nsm_lock);
 u32	__read_mostly		nsm_local_state;
 int	__read_mostly		nsm_use_hostnames;
 
+static struct kobject		*nsm_handles_kobj;
+
 static inline struct sockaddr *nsm_addr(const struct nsm_handle *nsm)
 {
 	return (struct sockaddr *)&nsm->sm_addr;
@@ -398,6 +400,31 @@ void nsm_release(struct nsm_handle *nsm)
 	}
 }
 
+/**
+ * nsm_init - Called when lockd module is loaded
+ *
+ */
+int nsm_init(void)
+{
+	nsm_handles_kobj = kobject_create_and_add("monitor", nlm_kobj);
+	if (nsm_handles_kobj == NULL)
+		return -ENOMEM;
+	return 0;
+}
+
+/**
+ * nsm_shutdown - Called when lockd module is about to be unloaded
+ *
+ */
+void nsm_shutdown(void)
+{
+	if (!list_empty(&nsm_handles)) {
+		printk(KERN_WARNING "NSM handles remain at shutdown");
+		return;
+	}
+	kobject_put(nsm_handles_kobj);
+}
+
 /*
  * XDR functions for NSM.
  *
diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c
index acfb6d7..e715ed7 100644
--- a/fs/lockd/svc.c
+++ b/fs/lockd/svc.c
@@ -526,9 +526,16 @@ static int __init init_nlm(void)
 		return -ENOMEM;
 	}
 
+	if (nsm_init()) {
+		nlm_host_shutdown();
+		kobject_put(nlm_kobj);
+		return -ENOMEM;
+	}
+
 #ifdef CONFIG_SYSCTL
 	nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
 	if (!nlm_sysctl_table) {
+		nsm_shutdown();
 		nlm_host_shutdown();
 		kobject_put(nlm_kobj);
 		return -ENOMEM;
@@ -545,6 +552,7 @@ static void __exit exit_nlm(void)
 #ifdef CONFIG_SYSCTL
 	unregister_sysctl_table(nlm_sysctl_table);
 #endif
+	nsm_shutdown();
 	nlm_host_shutdown();
 	kobject_put(nlm_kobj);
 }
diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h
index bdb87a6..8622a28 100644
--- a/include/linux/lockd/lockd.h
+++ b/include/linux/lockd/lockd.h
@@ -239,6 +239,8 @@ void		  nlm_host_rebooted(const struct nlm_reboot *);
 /*
  * Host monitoring
  */
+int		  nsm_init(void);
+void		  nsm_shutdown(void);
 int		  nsm_monitor(const struct nlm_host *host);
 void		  nsm_unmonitor(const struct nlm_host *host);