[PATCH v2 33/42] lockd: Convert server-side undefined procedures to xdrgen

[Chuck Lever <cel@kernel.org>]

From: Chuck Lever <chuck.lever@oracle.com>

The NLMv4 protocol defines several procedure slots that are
not implemented. These undefined procedures need proper
handling to return rpc_proc_unavail to clients that
mistakenly invoke them.

This patch converts the three undefined procedure entries
(slots 17, 18, and 19) to use xdrgen functions
nlm4_svc_decode_void and nlm4_svc_encode_void. The
nlm4svc_proc_unused function is also moved earlier in the
file to follow the convention of placing procedure
implementations before the procedure table.

The pc_argsize, pc_ressize, and pc_argzero fields are now
correctly set to zero since no arguments or results are
processed. The pc_xdrressize field is updated to XDR_void
to accurately reflect the response size.

This conversion completes the migration of all NLMv4
server-side procedures to use xdrgen-generated XDR
functions, improving type safety and eliminating
hand-written XDR code.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/lockd/svc4proc.c | 66 ++++++++++++++++++++++++---------------------
 1 file changed, 36 insertions(+), 30 deletions(-)

diff --git a/fs/lockd/svc4proc.c b/fs/lockd/svc4proc.c
index 7e936bd00a50..d8a5f662ab39 100644
--- a/fs/lockd/svc4proc.c
+++ b/fs/lockd/svc4proc.c
@@ -1020,6 +1020,18 @@ static __be32 nlm4svc_proc_sm_notify(struct svc_rqst *rqstp)
 	return rpc_success;
 }
 
+/**
+ * nlm4svc_proc_unused - stub for unused procedures
+ * @rqstp: RPC transaction context
+ *
+ * Returns:
+ *   %rpc_proc_unavail:	Program can't support procedure.
+ */
+static __be32 nlm4svc_proc_unused(struct svc_rqst *rqstp)
+{
+	return rpc_proc_unavail;
+}
+
 /*
  * SHARE: create a DOS share or alter existing share.
  */
@@ -1122,12 +1134,6 @@ nlm4svc_proc_free_all(struct svc_rqst *rqstp)
 	return rpc_success;
 }
 
-static __be32
-nlm4svc_proc_unused(struct svc_rqst *rqstp)
-{
-	return rpc_proc_unavail;
-}
-
 
 /*
  * NLM Server procedures.
@@ -1312,34 +1318,34 @@ static const struct svc_procedure nlm4svc_procedures[24] = {
 		.pc_name	= "SM_NOTIFY",
 	},
 	[17] = {
-		.pc_func = nlm4svc_proc_unused,
-		.pc_decode = nlm4svc_decode_void,
-		.pc_encode = nlm4svc_encode_void,
-		.pc_argsize = sizeof(struct nlm_void),
-		.pc_argzero = sizeof(struct nlm_void),
-		.pc_ressize = sizeof(struct nlm_void),
-		.pc_xdrressize = 0,
-		.pc_name = "UNUSED",
+		.pc_func	= nlm4svc_proc_unused,
+		.pc_decode	= nlm4_svc_decode_void,
+		.pc_encode	= nlm4_svc_encode_void,
+		.pc_argsize	= 0,
+		.pc_argzero	= 0,
+		.pc_ressize	= 0,
+		.pc_xdrressize	= XDR_void,
+		.pc_name	= "UNUSED",
 	},
 	[18] = {
-		.pc_func = nlm4svc_proc_unused,
-		.pc_decode = nlm4svc_decode_void,
-		.pc_encode = nlm4svc_encode_void,
-		.pc_argsize = sizeof(struct nlm_void),
-		.pc_argzero = sizeof(struct nlm_void),
-		.pc_ressize = sizeof(struct nlm_void),
-		.pc_xdrressize = 0,
-		.pc_name = "UNUSED",
+		.pc_func	= nlm4svc_proc_unused,
+		.pc_decode	= nlm4_svc_decode_void,
+		.pc_encode	= nlm4_svc_encode_void,
+		.pc_argsize	= 0,
+		.pc_argzero	= 0,
+		.pc_ressize	= 0,
+		.pc_xdrressize	= XDR_void,
+		.pc_name	= "UNUSED",
 	},
 	[19] = {
-		.pc_func = nlm4svc_proc_unused,
-		.pc_decode = nlm4svc_decode_void,
-		.pc_encode = nlm4svc_encode_void,
-		.pc_argsize = sizeof(struct nlm_void),
-		.pc_argzero = sizeof(struct nlm_void),
-		.pc_ressize = sizeof(struct nlm_void),
-		.pc_xdrressize = 0,
-		.pc_name = "UNUSED",
+		.pc_func	= nlm4svc_proc_unused,
+		.pc_decode	= nlm4_svc_decode_void,
+		.pc_encode	= nlm4_svc_encode_void,
+		.pc_argsize	= 0,
+		.pc_argzero	= 0,
+		.pc_ressize	= 0,
+		.pc_xdrressize	= XDR_void,
+		.pc_name	= "UNUSED",
 	},
 	[NLMPROC_SHARE] = {
 		.pc_func = nlm4svc_proc_share,
-- 
2.52.0