SUNRPC: New xdr_streams XDR encoder API

Now that all client-side XDR encoder routines use xdr_streams, there
should be no need to support the legacy calling sequence [rpc_rqst *,
__be32 *, RPC arg *] anywhere.  We can construct an xdr_stream in the
generic RPC code, instead of in each encoder function.

Also, all the client-side encoder functions return 0 now, making a
return value superfluous.  Take this opportunity to convert them to
return void instead.

This is a refactoring change.  It should not cause different behavior.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

3 files changed, 87 insertions, 123 deletions

diff --git a/fs/lockd/clnt4xdr.c b/fs/lockd/clnt4xdr.c
index 1a1c3e21ed2c..974f1d9cd323 100644
--- a/fs/lockd/clnt4xdr.c
+++ b/fs/lockd/clnt4xdr.c
@@ -385,17 +385,15 @@ static void encode_nlm4_lock(struct xdr_stream *xdr,
  *		struct nlm4_lock alock;
  *	};
  */
-static int nlm4_xdr_enc_testargs(struct rpc_rqst *req, __be32 *p,
-				 const struct nlm_args *args)
+static void nlm4_xdr_enc_testargs(struct rpc_rqst *req,
+				  struct xdr_stream *xdr,
+				  const struct nlm_args *args)
 {
 	const struct nlm_lock *lock = &args->lock;
-	struct xdr_stream xdr;
 
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &args->cookie);
-	encode_bool(&xdr, lock->fl.fl_type == F_WRLCK);
-	encode_nlm4_lock(&xdr, lock);
-	return 0;
+	encode_cookie(xdr, &args->cookie);
+	encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
+	encode_nlm4_lock(xdr, lock);
 }
 
 /*
@@ -408,20 +406,18 @@ static int nlm4_xdr_enc_testargs(struct rpc_rqst *req, __be32 *p,
  *		int state;
  *	};
  */
-static int nlm4_xdr_enc_lockargs(struct rpc_rqst *req, __be32 *p,
-				 const struct nlm_args *args)
+static void nlm4_xdr_enc_lockargs(struct rpc_rqst *req,
+				  struct xdr_stream *xdr,
+				  const struct nlm_args *args)
 {
 	const struct nlm_lock *lock = &args->lock;
-	struct xdr_stream xdr;
 
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &args->cookie);
-	encode_bool(&xdr, args->block);
-	encode_bool(&xdr, lock->fl.fl_type == F_WRLCK);
-	encode_nlm4_lock(&xdr, lock);
-	encode_bool(&xdr, args->reclaim);
-	encode_int32(&xdr, args->state);
-	return 0;
+	encode_cookie(xdr, &args->cookie);
+	encode_bool(xdr, args->block);
+	encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
+	encode_nlm4_lock(xdr, lock);
+	encode_bool(xdr, args->reclaim);
+	encode_int32(xdr, args->state);
 }
 
 /*
@@ -432,18 +428,16 @@ static int nlm4_xdr_enc_lockargs(struct rpc_rqst *req, __be32 *p,
  *		struct nlm4_lock alock;
  *	};
  */
-static int nlm4_xdr_enc_cancargs(struct rpc_rqst *req, __be32 *p,
-				 const struct nlm_args *args)
+static void nlm4_xdr_enc_cancargs(struct rpc_rqst *req,
+				  struct xdr_stream *xdr,
+				  const struct nlm_args *args)
 {
 	const struct nlm_lock *lock = &args->lock;
-	struct xdr_stream xdr;
 
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &args->cookie);
-	encode_bool(&xdr, args->block);
-	encode_bool(&xdr, lock->fl.fl_type == F_WRLCK);
-	encode_nlm4_lock(&xdr, lock);
-	return 0;
+	encode_cookie(xdr, &args->cookie);
+	encode_bool(xdr, args->block);
+	encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
+	encode_nlm4_lock(xdr, lock);
 }
 
 /*
@@ -452,16 +446,14 @@ static int nlm4_xdr_enc_cancargs(struct rpc_rqst *req, __be32 *p,
  *		struct nlm4_lock alock;
  *	};
  */
-static int nlm4_xdr_enc_unlockargs(struct rpc_rqst *req, __be32 *p,
-				   const struct nlm_args *args)
+static void nlm4_xdr_enc_unlockargs(struct rpc_rqst *req,
+				    struct xdr_stream *xdr,
+				    const struct nlm_args *args)
 {
 	const struct nlm_lock *lock = &args->lock;
-	struct xdr_stream xdr;
 
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &args->cookie);
-	encode_nlm4_lock(&xdr, lock);
-	return 0;
+	encode_cookie(xdr, &args->cookie);
+	encode_nlm4_lock(xdr, lock);
 }
 
 /*
@@ -470,15 +462,12 @@ static int nlm4_xdr_enc_unlockargs(struct rpc_rqst *req, __be32 *p,
  *		nlm4_stat stat;
  *	};
  */
-static int nlm4_xdr_enc_res(struct rpc_rqst *req, __be32 *p,
-			    const struct nlm_res *result)
+static void nlm4_xdr_enc_res(struct rpc_rqst *req,
+			     struct xdr_stream *xdr,
+			     const struct nlm_res *result)
 {
-	struct xdr_stream xdr;
-
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &result->cookie);
-	encode_nlm4_stat(&xdr, result->status);
-	return 0;
+	encode_cookie(xdr, &result->cookie);
+	encode_nlm4_stat(xdr, result->status);
 }
 
 /*
@@ -494,17 +483,14 @@ static int nlm4_xdr_enc_res(struct rpc_rqst *req, __be32 *p,
  *		nlm4_testrply test_stat;
  *	};
  */
-static int nlm4_xdr_enc_testres(struct rpc_rqst *req, __be32 *p,
-				const struct nlm_res *result)
+static void nlm4_xdr_enc_testres(struct rpc_rqst *req,
+				 struct xdr_stream *xdr,
+				 const struct nlm_res *result)
 {
-	struct xdr_stream xdr;
-
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &result->cookie);
-	encode_nlm4_stat(&xdr, result->status);
+	encode_cookie(xdr, &result->cookie);
+	encode_nlm4_stat(xdr, result->status);
 	if (result->status == nlm_lck_denied)
-		encode_nlm4_holder(&xdr, result);
-	return 0;
+		encode_nlm4_holder(xdr, result);
 }
 
 
@@ -588,7 +574,7 @@ out:
 #define PROC(proc, argtype, restype)					\
 [NLMPROC_##proc] = {							\
 	.p_proc      = NLMPROC_##proc,					\
-	.p_encode    = (kxdrproc_t)nlm4_xdr_enc_##argtype,		\
+	.p_encode    = (kxdreproc_t)nlm4_xdr_enc_##argtype,		\
 	.p_decode    = (kxdrproc_t)nlm4_xdr_dec_##restype,		\
 	.p_arglen    = NLM4_##argtype##_sz,				\
 	.p_replen    = NLM4_##restype##_sz,				\
diff --git a/fs/lockd/clntxdr.c b/fs/lockd/clntxdr.c
index 0472f2aff509..c6fda8fb1c5b 100644
--- a/fs/lockd/clntxdr.c
+++ b/fs/lockd/clntxdr.c
@@ -378,17 +378,15 @@ static void encode_nlm_lock(struct xdr_stream *xdr,
  *		struct nlm_lock alock;
  *	};
  */
-static int nlm_xdr_enc_testargs(struct rpc_rqst *req, __be32 *p,
-				const struct nlm_args *args)
+static void nlm_xdr_enc_testargs(struct rpc_rqst *req,
+				 struct xdr_stream *xdr,
+				 const struct nlm_args *args)
 {
 	const struct nlm_lock *lock = &args->lock;
-	struct xdr_stream xdr;
 
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &args->cookie);
-	encode_bool(&xdr, lock->fl.fl_type == F_WRLCK);
-	encode_nlm_lock(&xdr, lock);
-	return 0;
+	encode_cookie(xdr, &args->cookie);
+	encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
+	encode_nlm_lock(xdr, lock);
 }
 
 /*
@@ -401,20 +399,18 @@ static int nlm_xdr_enc_testargs(struct rpc_rqst *req, __be32 *p,
  *		int state;
  *	};
  */
-static int nlm_xdr_enc_lockargs(struct rpc_rqst *req, __be32 *p,
-				const struct nlm_args *args)
+static void nlm_xdr_enc_lockargs(struct rpc_rqst *req,
+				 struct xdr_stream *xdr,
+				 const struct nlm_args *args)
 {
 	const struct nlm_lock *lock = &args->lock;
-	struct xdr_stream xdr;
 
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &args->cookie);
-	encode_bool(&xdr, args->block);
-	encode_bool(&xdr, lock->fl.fl_type == F_WRLCK);
-	encode_nlm_lock(&xdr, lock);
-	encode_bool(&xdr, args->reclaim);
-	encode_int32(&xdr, args->state);
-	return 0;
+	encode_cookie(xdr, &args->cookie);
+	encode_bool(xdr, args->block);
+	encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
+	encode_nlm_lock(xdr, lock);
+	encode_bool(xdr, args->reclaim);
+	encode_int32(xdr, args->state);
 }
 
 /*
@@ -425,18 +421,16 @@ static int nlm_xdr_enc_lockargs(struct rpc_rqst *req, __be32 *p,
  *		struct nlm_lock alock;
  *	};
  */
-static int nlm_xdr_enc_cancargs(struct rpc_rqst *req, __be32 *p,
-				const struct nlm_args *args)
+static void nlm_xdr_enc_cancargs(struct rpc_rqst *req,
+				 struct xdr_stream *xdr,
+				 const struct nlm_args *args)
 {
 	const struct nlm_lock *lock = &args->lock;
-	struct xdr_stream xdr;
 
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &args->cookie);
-	encode_bool(&xdr, args->block);
-	encode_bool(&xdr, lock->fl.fl_type == F_WRLCK);
-	encode_nlm_lock(&xdr, lock);
-	return 0;
+	encode_cookie(xdr, &args->cookie);
+	encode_bool(xdr, args->block);
+	encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
+	encode_nlm_lock(xdr, lock);
 }
 
 /*
@@ -445,16 +439,14 @@ static int nlm_xdr_enc_cancargs(struct rpc_rqst *req, __be32 *p,
  *		struct nlm_lock alock;
  *	};
  */
-static int nlm_xdr_enc_unlockargs(struct rpc_rqst *req, __be32 *p,
-				  const struct nlm_args *args)
+static void nlm_xdr_enc_unlockargs(struct rpc_rqst *req,
+				   struct xdr_stream *xdr,
+				   const struct nlm_args *args)
 {
 	const struct nlm_lock *lock = &args->lock;
-	struct xdr_stream xdr;
 
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &args->cookie);
-	encode_nlm_lock(&xdr, lock);
-	return 0;
+	encode_cookie(xdr, &args->cookie);
+	encode_nlm_lock(xdr, lock);
 }
 
 /*
@@ -463,15 +455,12 @@ static int nlm_xdr_enc_unlockargs(struct rpc_rqst *req, __be32 *p,
  *		nlm_stat stat;
  *	};
  */
-static int nlm_xdr_enc_res(struct rpc_rqst *req, __be32 *p,
-			   const struct nlm_res *result)
+static void nlm_xdr_enc_res(struct rpc_rqst *req,
+			    struct xdr_stream *xdr,
+			    const struct nlm_res *result)
 {
-	struct xdr_stream xdr;
-
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &result->cookie);
-	encode_nlm_stat(&xdr, result->status);
-	return 0;
+	encode_cookie(xdr, &result->cookie);
+	encode_nlm_stat(xdr, result->status);
 }
 
 /*
@@ -494,16 +483,13 @@ static void encode_nlm_testrply(struct xdr_stream *xdr,
 		encode_nlm_holder(xdr, result);
 }
 
-static int nlm_xdr_enc_testres(struct rpc_rqst *req, __be32 *p,
-			       const struct nlm_res *result)
+static void nlm_xdr_enc_testres(struct rpc_rqst *req,
+				struct xdr_stream *xdr,
+				const struct nlm_res *result)
 {
-	struct xdr_stream xdr;
-
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_cookie(&xdr, &result->cookie);
-	encode_nlm_stat(&xdr, result->status);
-	encode_nlm_testrply(&xdr, result);
-	return 0;
+	encode_cookie(xdr, &result->cookie);
+	encode_nlm_stat(xdr, result->status);
+	encode_nlm_testrply(xdr, result);
 }
 
 
@@ -586,7 +572,7 @@ out:
 #define PROC(proc, argtype, restype)	\
 [NLMPROC_##proc] = {							\
 	.p_proc      = NLMPROC_##proc,					\
-	.p_encode    = (kxdrproc_t)nlm_xdr_enc_##argtype,		\
+	.p_encode    = (kxdreproc_t)nlm_xdr_enc_##argtype,		\
 	.p_decode    = (kxdrproc_t)nlm_xdr_dec_##restype,		\
 	.p_arglen    = NLM_##argtype##_sz,				\
 	.p_replen    = NLM_##restype##_sz,				\
diff --git a/fs/lockd/mon.c b/fs/lockd/mon.c
index d812818d0258..baa77bc9d825 100644
--- a/fs/lockd/mon.c
+++ b/fs/lockd/mon.c
@@ -459,25 +459,17 @@ static void encode_priv(struct xdr_stream *xdr, const struct nsm_args *argp)
 	xdr_encode_opaque_fixed(p, argp->priv->data, SM_PRIV_SIZE);
 }
 
-static int xdr_enc_mon(struct rpc_rqst *req, __be32 *p,
-		       const struct nsm_args *argp)
+static void nsm_xdr_enc_mon(struct rpc_rqst *req, struct xdr_stream *xdr,
+			    const struct nsm_args *argp)
 {
-	struct xdr_stream xdr;
-
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_mon_id(&xdr, argp);
-	encode_priv(&xdr, argp);
-	return 0;
+	encode_mon_id(xdr, argp);
+	encode_priv(xdr, argp);
 }
 
-static int xdr_enc_unmon(struct rpc_rqst *req, __be32 *p,
-			 const struct nsm_args *argp)
+static void nsm_xdr_enc_unmon(struct rpc_rqst *req, struct xdr_stream *xdr,
+			      const struct nsm_args *argp)
 {
-	struct xdr_stream xdr;
-
-	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
-	encode_mon_id(&xdr, argp);
-	return 0;
+	encode_mon_id(xdr, argp);
 }
 
 static int xdr_dec_stat_res(struct rpc_rqst *rqstp, __be32 *p,
@@ -524,7 +516,7 @@ static int xdr_dec_stat(struct rpc_rqst *rqstp, __be32 *p,
 static struct rpc_procinfo	nsm_procedures[] = {
 [NSMPROC_MON] = {
 		.p_proc		= NSMPROC_MON,
-		.p_encode	= (kxdrproc_t)xdr_enc_mon,
+		.p_encode	= (kxdreproc_t)nsm_xdr_enc_mon,
 		.p_decode	= (kxdrproc_t)xdr_dec_stat_res,
 		.p_arglen	= SM_mon_sz,
 		.p_replen	= SM_monres_sz,
@@ -533,7 +525,7 @@ static struct rpc_procinfo	nsm_procedures[] = {
 	},
 [NSMPROC_UNMON] = {
 		.p_proc		= NSMPROC_UNMON,
-		.p_encode	= (kxdrproc_t)xdr_enc_unmon,
+		.p_encode	= (kxdreproc_t)nsm_xdr_enc_unmon,
 		.p_decode	= (kxdrproc_t)xdr_dec_stat,
 		.p_arglen	= SM_mon_id_sz,
 		.p_replen	= SM_unmonres_sz,