SUNRPC: Move svcxdr_init_encode() into ->accept methods

Refactor: So that the overhaul of each ->accept method can be done
in separate smaller patches, temporarily move the
svcxdr_init_encode() call into those methods.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

net/sunrpc/auth_gss/svcauth_gss.c

@@ -1250,6 +1250,7 @@ svcauth_gss_legacy_init(struct svc_rqst *rqstp,
 		goto out;
 
 	ret = SVC_COMPLETE;
+	svcxdr_init_encode(rqstp);
 out:
 	cache_put(&rsip->h, sn->rsi_cache);
 	return ret;
@@ -1378,6 +1379,7 @@ static int svcauth_gss_proxy_init(struct svc_rqst *rqstp,
 		goto out;
 
 	ret = SVC_COMPLETE;
+	svcxdr_init_encode(rqstp);
 out:
 	gss_free_in_token_pages(&ud.in_token);
 	gssp_free_upcall_data(&ud);
@@ -1680,6 +1682,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp)
 		rqstp->rq_auth_stat = rpc_autherr_badcred;
 		switch (gc->gc_svc) {
 		case RPC_GSS_SVC_NONE:
+			svcxdr_init_encode(rqstp);
 			break;
 		case RPC_GSS_SVC_INTEGRITY:
 			/* placeholders for length and seq. number: */
@@ -1689,6 +1692,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp)
 						     rsci->mechctx))
 				goto garbage_args;
 			rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE;
+			svcxdr_init_encode(rqstp);
 			break;
 		case RPC_GSS_SVC_PRIVACY:
 			/* placeholders for length and seq. number: */
@@ -1698,6 +1702,7 @@ svcauth_gss_accept(struct svc_rqst *rqstp)
 						    rsci->mechctx))
 				goto garbage_args;
 			rqstp->rq_auth_slack = RPC_MAX_AUTH_SIZE * 2;
+			svcxdr_init_encode(rqstp);
 			break;
 		default:
 			goto auth_err;

net/sunrpc/svc.c

@@ -1312,16 +1312,14 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *resv)
 	serv->sv_stats->rpccnt++;
 	trace_svc_process(rqstp, progp->pg_name);
 
-	/* Build the reply header. */
-	statp = resv->iov_base +resv->iov_len;
-	svc_putnl(resv, RPC_SUCCESS);
+	statp = xdr_reserve_space(&rqstp->rq_res_stream, XDR_UNIT);
+	*statp = rpc_success;
 
 	/* un-reserve some of the out-queue now that we have a
 	 * better idea of reply size
 	 */
 	if (procp->pc_xdrressize)
 		svc_reserve_auth(rqstp, procp->pc_xdrressize<<2);
-	svcxdr_init_encode(rqstp);
 
 	/* Call the function that processes the request. */
 	rc = process.dispatch(rqstp, statp);

net/sunrpc/svcauth_unix.c

@@ -778,6 +778,7 @@ svcauth_null_accept(struct svc_rqst *rqstp)
 	svc_putnl(resv, 0);
 
 	rqstp->rq_cred.cr_flavor = RPC_AUTH_NULL;
+	svcxdr_init_encode(rqstp);
 	return SVC_OK;
 }
 
@@ -865,6 +866,7 @@ svcauth_tls_accept(struct svc_rqst *rqstp)
 		svc_putnl(resv, 0);
 
 	rqstp->rq_cred.cr_flavor = RPC_AUTH_TLS;
+	svcxdr_init_encode(rqstp);
 	return SVC_OK;
 }
 
@@ -960,6 +962,7 @@ svcauth_unix_accept(struct svc_rqst *rqstp)
 	svc_putnl(resv, 0);
 
 	rqstp->rq_cred.cr_flavor = RPC_AUTH_UNIX;
+	svcxdr_init_encode(rqstp);
 	return SVC_OK;
 
 badcred: