[PATCH v1 15/36] lockd: Use xdrgen XDR functions for the NLMv4 GRANTED procedure

[Chuck Lever <cel@kernel.org>]

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

Replace the NLMPROC4_GRANTED entry in the nlm_procedures4 array with
an entry that uses the xdrgen-built XDR functions for that
procedure. Helper functions are introduced which will be used here
and in subsequent patches.

The .pc_argzero field is now set to zero for the NLMv4 GRANTED
procedure. The xdrgen decoders are trusted to initialize all
arguments in the argp->xdrgen field, making the early defensive
memset unnecessary. The remaining argp fields are cleared as needed.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/lockd/svc4proc.c | 54 ++++++++++++++++++++++++++++++++++++---------
 1 file changed, 44 insertions(+), 10 deletions(-)

diff --git a/fs/lockd/svc4proc.c b/fs/lockd/svc4proc.c
index 22f676df16e8..fc446639095a 100644
--- a/fs/lockd/svc4proc.c
+++ b/fs/lockd/svc4proc.c
@@ -545,10 +545,44 @@ __nlm4svc_proc_granted(struct svc_rqst *rqstp, struct nlm_res *resp)
 	return rpc_success;
 }
 
+/**
+ * nlm4svc_proc_granted - GRANTED: Blocked lock has been granted
+ * @rqstp: RPC transaction context
+ *
+ * Returns:
+ *   %rpc_success:		RPC executed successfully.
+ *
+ * Permissible procedure status codes:
+ *   %NLM4_GRANTED:		The requested lock was granted.
+ *   %NLM4_DENIED:		The server could not allocate the resources
+ *				needed to process the request.
+ *   %NLM4_DENIED_GRACE_PERIOD:	The server has recently restarted and is
+ *				re-establishing existing locks, and is not
+ *				yet ready to accept normal service requests.
+ */
 static __be32
 nlm4svc_proc_granted(struct svc_rqst *rqstp)
 {
-	return __nlm4svc_proc_granted(rqstp, rqstp->rq_resp);
+	struct nlm4_testargs_wrapper *argp = rqstp->rq_argp;
+	struct nlm4_res_wrapper *resp = rqstp->rq_resp;
+	struct nlm4_lock *alock = &argp->xdrgen.alock;
+	struct nlm_lock *lock = &argp->lock;
+
+	resp->xdrgen.cookie = argp->xdrgen.cookie;
+
+	resp->xdrgen.stat.stat = nlm_lck_denied;
+	if (alock->fh.len > NFS_MAXFHSIZE)
+		goto out;
+
+	lock->fh.size = alock->fh.len;
+	memcpy(lock->fh.data, alock->fh.data, alock->fh.len);
+	lock->svid = alock->svid;
+	nlm4svc_set_file_lock_range(&lock->fl, alock->l_offset, alock->l_len);
+
+	resp->xdrgen.stat.stat = nlmclnt_grant(svc_addr(rqstp), lock);
+
+out:
+	return rpc_success;
 }
 
 /*
@@ -843,15 +877,15 @@ const struct svc_procedure nlmsvc_procedures4[24] = {
 		.pc_xdrressize	= NLM4_nlm4_res_sz,
 		.pc_name	= "UNLOCK",
 	},
-	[NLMPROC_GRANTED] = {
-		.pc_func = nlm4svc_proc_granted,
-		.pc_decode = nlm4svc_decode_testargs,
-		.pc_encode = nlm4svc_encode_res,
-		.pc_argsize = sizeof(struct nlm_args),
-		.pc_argzero = sizeof(struct nlm_args),
-		.pc_ressize = sizeof(struct nlm_res),
-		.pc_xdrressize = Ck+St,
-		.pc_name = "GRANTED",
+	[NLMPROC4_GRANTED] = {
+		.pc_func	= nlm4svc_proc_granted,
+		.pc_decode	= nlm4_svc_decode_nlm4_testargs,
+		.pc_encode	= nlm4_svc_encode_nlm4_res,
+		.pc_argsize	= sizeof(struct nlm4_testargs_wrapper),
+		.pc_argzero	= 0,
+		.pc_ressize	= sizeof(struct nlm4_res_wrapper),
+		.pc_xdrressize	= NLM4_nlm4_res_sz,
+		.pc_name	= "GRANTED",
 	},
 	[NLMPROC_TEST_MSG] = {
 		.pc_func = nlm4svc_proc_test_msg,
-- 
2.52.0