[PATCH 1/5] SUNRPC: allow a service to opt out of rpcbind registration

[Jeff Layton <jlayton@kernel.org>]

svc_bind() creates the local rpcbind client, and svc_register() then
makes one synchronous call for each program and version. Both run under
the caller's mutex. A caller that registers from userland needs neither.

Add sv_no_rpcbind to struct svc_serv, and fix up the code to honor it.
No caller sets the flag yet, so behaviour does not change.

Assisted-by: LLM
Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 include/linux/sunrpc/svc.h | 2 ++
 net/sunrpc/svc.c           | 5 +++++
 net/sunrpc/svc_xprt.c      | 2 +-
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h
index 5fa9417e034d..7f09db6a360c 100644
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -87,6 +87,8 @@ struct svc_serv {
 	char *			sv_name;	/* service name */
 
 	bool			sv_is_pooled;	/* is this a pooled service? */
+	/* Caller registers with rpcbind itself. Set before svc_bind(). */
+	bool			sv_no_rpcbind;
 	struct svc_pool *	sv_pools;	/* array of thread pools */
 	int			(*sv_threadfn)(void *data);
 
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index f73412e123a1..7e23af94a719 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -337,6 +337,8 @@ static int svc_uses_rpcbind(struct svc_serv *serv)
 
 int svc_bind(struct svc_serv *serv, struct net *net)
 {
+	if (serv->sv_no_rpcbind)
+		return 0;
 	if (!svc_uses_rpcbind(serv))
 		return 0;
 	return svc_rpcb_setup(serv, net);
@@ -1235,6 +1237,9 @@ int svc_register(struct svc_serv *serv, struct net *net,
 	if (proto == 0 && port == 0)
 		return -EINVAL;
 
+	if (serv->sv_no_rpcbind)
+		return 0;
+
 	for (p = 0; p < serv->sv_nprogs; p++) {
 		struct svc_program *progp = &serv->sv_programs[p];
 
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index d5634dd6d6cc..1a2c87e4d951 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -1266,7 +1266,7 @@ void svc_xprt_destroy_all(struct svc_serv *serv, struct net *net,
 		msleep(delay++);
 	}
 
-	if (unregister)
+	if (unregister && !serv->sv_no_rpcbind)
 		svc_rpcb_cleanup(serv, net);
 }
 EXPORT_SYMBOL_GPL(svc_xprt_destroy_all);

-- 
2.55.0