NFSD: Distinguish per-net namespace initialization

I find the naming of nfsd_init_net() and nfsd_startup_net() to be
confusingly similar. Rename the namespace initialization and tear-
down ops and add comments to distinguish their separate purposes.

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

Author: chucklever

fs/nfsd/nfsctl.c

@@ -1494,7 +1494,17 @@ static int create_proc_exports_entry(void)
 
 unsigned int nfsd_net_id;
 
-static __net_init int nfsd_init_net(struct net *net)
+/**
+ * nfsd_net_init - Prepare the nfsd_net portion of a new net namespace
+ * @net: a freshly-created network namespace
+ *
+ * This information stays around as long as the network namespace is
+ * alive whether or not there is an NFSD instance running in the
+ * namespace.
+ *
+ * Returns zero on success, or a negative errno otherwise.
+ */
+static __net_init int nfsd_net_init(struct net *net)
 {
 	int retval;
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
@@ -1524,7 +1534,12 @@ static __net_init int nfsd_init_net(struct net *net)
 	return retval;
 }
 
-static __net_exit void nfsd_exit_net(struct net *net)
+/**
+ * nfsd_net_exit - Release the nfsd_net portion of a net namespace
+ * @net: a network namespace that is about to be destroyed
+ *
+ */
+static __net_exit void nfsd_net_exit(struct net *net)
 {
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);
 
@@ -1535,8 +1550,8 @@ static __net_exit void nfsd_exit_net(struct net *net)
 }
 
 static struct pernet_operations nfsd_net_ops = {
-	.init = nfsd_init_net,
-	.exit = nfsd_exit_net,
+	.init = nfsd_net_init,
+	.exit = nfsd_net_exit,
 	.id   = &nfsd_net_id,
 	.size = sizeof(struct nfsd_net),
 };

fs/nfsd/nfssvc.c

@@ -402,6 +402,11 @@ void nfsd_reset_write_verifier(struct nfsd_net *nn)
 	write_sequnlock(&nn->writeverf_lock);
 }
 
+/*
+ * Crank up a set of per-namespace resources for a new NFSD instance,
+ * including lockd, a duplicate reply cache, an open file cache
+ * instance, and a cache of NFSv4 state objects.
+ */
 static int nfsd_startup_net(struct net *net, const struct cred *cred)
 {
 	struct nfsd_net *nn = net_generic(net, nfsd_net_id);