SUNRPC: New xdr_streams XDR decoder API

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

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, 33 insertions, 37 deletions

diff --git a/fs/lockd/clnt4xdr.c b/fs/lockd/clnt4xdr.c
index 974f1d9cd32..f848b52c67b 100644
--- a/fs/lockd/clnt4xdr.c
+++ b/fs/lockd/clnt4xdr.c
@@ -529,17 +529,16 @@ out:
 	return error;
 }
 
-static int nlm4_xdr_dec_testres(struct rpc_rqst *req, __be32 *p,
+static int nlm4_xdr_dec_testres(struct rpc_rqst *req,
+				struct xdr_stream *xdr,
 				struct nlm_res *result)
 {
-	struct xdr_stream xdr;
 	int error;
 
-	xdr_init_decode(&xdr, &req->rq_rcv_buf, p);
-	error = decode_cookie(&xdr, &result->cookie);
+	error = decode_cookie(xdr, &result->cookie);
 	if (unlikely(error))
 		goto out;
-	error = decode_nlm4_testrply(&xdr, result);
+	error = decode_nlm4_testrply(xdr, result);
 out:
 	return error;
 }
@@ -550,17 +549,16 @@ out:
  *		nlm4_stat stat;
  *	};
  */
-static int nlm4_xdr_dec_res(struct rpc_rqst *req, __be32 *p,
+static int nlm4_xdr_dec_res(struct rpc_rqst *req,
+			    struct xdr_stream *xdr,
 			    struct nlm_res *result)
 {
-	struct xdr_stream xdr;
 	int error;
 
-	xdr_init_decode(&xdr, &req->rq_rcv_buf, p);
-	error = decode_cookie(&xdr, &result->cookie);
+	error = decode_cookie(xdr, &result->cookie);
 	if (unlikely(error))
 		goto out;
-	error = decode_nlm4_stat(&xdr, &result->status);
+	error = decode_nlm4_stat(xdr, &result->status);
 out:
 	return error;
 }
@@ -575,7 +573,7 @@ out:
 [NLMPROC_##proc] = {							\
 	.p_proc      = NLMPROC_##proc,					\
 	.p_encode    = (kxdreproc_t)nlm4_xdr_enc_##argtype,		\
-	.p_decode    = (kxdrproc_t)nlm4_xdr_dec_##restype,		\
+	.p_decode    = (kxdrdproc_t)nlm4_xdr_dec_##restype,		\
 	.p_arglen    = NLM4_##argtype##_sz,				\
 	.p_replen    = NLM4_##restype##_sz,				\
 	.p_statidx   = NLMPROC_##proc,					\
diff --git a/fs/lockd/clntxdr.c b/fs/lockd/clntxdr.c
index c6fda8fb1c5..180ac34feb9 100644
--- a/fs/lockd/clntxdr.c
+++ b/fs/lockd/clntxdr.c
@@ -527,17 +527,16 @@ out:
 	return error;
 }
 
-static int nlm_xdr_dec_testres(struct rpc_rqst *req, __be32 *p,
+static int nlm_xdr_dec_testres(struct rpc_rqst *req,
+			       struct xdr_stream *xdr,
 			       struct nlm_res *result)
 {
-	struct xdr_stream xdr;
 	int error;
 
-	xdr_init_decode(&xdr, &req->rq_rcv_buf, p);
-	error = decode_cookie(&xdr, &result->cookie);
+	error = decode_cookie(xdr, &result->cookie);
 	if (unlikely(error))
 		goto out;
-	error = decode_nlm_testrply(&xdr, result);
+	error = decode_nlm_testrply(xdr, result);
 out:
 	return error;
 }
@@ -548,17 +547,16 @@ out:
  *		nlm_stat stat;
  *	};
  */
-static int nlm_xdr_dec_res(struct rpc_rqst *req, __be32 *p,
+static int nlm_xdr_dec_res(struct rpc_rqst *req,
+			   struct xdr_stream *xdr,
 			   struct nlm_res *result)
 {
-	struct xdr_stream xdr;
 	int error;
 
-	xdr_init_decode(&xdr, &req->rq_rcv_buf, p);
-	error = decode_cookie(&xdr, &result->cookie);
+	error = decode_cookie(xdr, &result->cookie);
 	if (unlikely(error))
 		goto out;
-	error = decode_nlm_stat(&xdr, &result->status);
+	error = decode_nlm_stat(xdr, &result->status);
 out:
 	return error;
 }
@@ -573,7 +571,7 @@ out:
 [NLMPROC_##proc] = {							\
 	.p_proc      = NLMPROC_##proc,					\
 	.p_encode    = (kxdreproc_t)nlm_xdr_enc_##argtype,		\
-	.p_decode    = (kxdrproc_t)nlm_xdr_dec_##restype,		\
+	.p_decode    = (kxdrdproc_t)nlm_xdr_dec_##restype,		\
 	.p_arglen    = NLM_##argtype##_sz,				\
 	.p_replen    = NLM_##restype##_sz,				\
 	.p_statidx   = NLMPROC_##proc,					\
diff --git a/fs/lockd/mon.c b/fs/lockd/mon.c
index baa77bc9d82..23d7451b293 100644
--- a/fs/lockd/mon.c
+++ b/fs/lockd/mon.c
@@ -472,35 +472,35 @@ static void nsm_xdr_enc_unmon(struct rpc_rqst *req, struct xdr_stream *xdr,
 	encode_mon_id(xdr, argp);
 }
 
-static int xdr_dec_stat_res(struct rpc_rqst *rqstp, __be32 *p,
-			    struct nsm_res *resp)
+static int nsm_xdr_dec_stat_res(struct rpc_rqst *rqstp,
+				struct xdr_stream *xdr,
+				struct nsm_res *resp)
 {
-	struct xdr_stream xdr;
+	__be32 *p;
 
-	xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
-	p = xdr_inline_decode(&xdr, 4 + 4);
+	p = xdr_inline_decode(xdr, 4 + 4);
 	if (unlikely(p == NULL))
 		return -EIO;
 	resp->status = be32_to_cpup(p++);
 	resp->state = be32_to_cpup(p);
 
-	dprintk("lockd: xdr_dec_stat_res status %d state %d\n",
-			resp->status, resp->state);
+	dprintk("lockd: %s status %d state %d\n",
+		__func__, resp->status, resp->state);
 	return 0;
 }
 
-static int xdr_dec_stat(struct rpc_rqst *rqstp, __be32 *p,
-			struct nsm_res *resp)
+static int nsm_xdr_dec_stat(struct rpc_rqst *rqstp,
+			    struct xdr_stream *xdr,
+			    struct nsm_res *resp)
 {
-	struct xdr_stream xdr;
+	__be32 *p;
 
-	xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
-	p = xdr_inline_decode(&xdr, 4);
+	p = xdr_inline_decode(xdr, 4);
 	if (unlikely(p == NULL))
 		return -EIO;
 	resp->state = be32_to_cpup(p);
 
-	dprintk("lockd: xdr_dec_stat state %d\n", resp->state);
+	dprintk("lockd: %s state %d\n", __func__, resp->state);
 	return 0;
 }
 
@@ -517,7 +517,7 @@ static struct rpc_procinfo	nsm_procedures[] = {
 [NSMPROC_MON] = {
 		.p_proc		= NSMPROC_MON,
 		.p_encode	= (kxdreproc_t)nsm_xdr_enc_mon,
-		.p_decode	= (kxdrproc_t)xdr_dec_stat_res,
+		.p_decode	= (kxdrdproc_t)nsm_xdr_dec_stat_res,
 		.p_arglen	= SM_mon_sz,
 		.p_replen	= SM_monres_sz,
 		.p_statidx	= NSMPROC_MON,
@@ -526,7 +526,7 @@ static struct rpc_procinfo	nsm_procedures[] = {
 [NSMPROC_UNMON] = {
 		.p_proc		= NSMPROC_UNMON,
 		.p_encode	= (kxdreproc_t)nsm_xdr_enc_unmon,
-		.p_decode	= (kxdrproc_t)xdr_dec_stat,
+		.p_decode	= (kxdrdproc_t)nsm_xdr_dec_stat,
 		.p_arglen	= SM_mon_id_sz,
 		.p_replen	= SM_unmonres_sz,
 		.p_statidx	= NSMPROC_UNMON,