NFSD: Update the NFSv3 WRITE3res encoder to use struct xdr_stream

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

fs/nfsd/nfs3xdr.c

@@ -131,6 +131,19 @@ encode_fh(__be32 *p, struct svc_fh *fhp)
 	return p + XDR_QUADLEN(size);
 }
 
+static bool
+svcxdr_encode_writeverf3(struct xdr_stream *xdr, const __be32 *verf)
+{
+	__be32 *p;
+
+	p = xdr_reserve_space(xdr, NFS3_WRITEVERFSIZE);
+	if (!p)
+		return false;
+	memcpy(p, verf, NFS3_WRITEVERFSIZE);
+
+	return true;
+}
+
 static bool
 svcxdr_decode_filename3(struct xdr_stream *xdr, char **name, unsigned int *len)
 {
@@ -1038,17 +1051,28 @@ nfs3svc_encode_readres(struct svc_rqst *rqstp, __be32 *p)
 int
 nfs3svc_encode_writeres(struct svc_rqst *rqstp, __be32 *p)
 {
+	struct xdr_stream *xdr = &rqstp->rq_res_stream;
 	struct nfsd3_writeres *resp = rqstp->rq_resp;
 
-	*p++ = resp->status;
-	p = encode_wcc_data(rqstp, p, &resp->fh);
-	if (resp->status == 0) {
-		*p++ = htonl(resp->count);
-		*p++ = htonl(resp->committed);
-		*p++ = resp->verf[0];
-		*p++ = resp->verf[1];
+	if (!svcxdr_encode_nfsstat3(xdr, resp->status))
+		return 0;
+	switch (resp->status) {
+	case nfs_ok:
+		if (!svcxdr_encode_wcc_data(rqstp, xdr, &resp->fh))
+			return 0;
+		if (xdr_stream_encode_u32(xdr, resp->count) < 0)
+			return 0;
+		if (xdr_stream_encode_u32(xdr, resp->committed) < 0)
+			return 0;
+		if (!svcxdr_encode_writeverf3(xdr, resp->verf))
+			return 0;
+		break;
+	default:
+		if (!svcxdr_encode_wcc_data(rqstp, xdr, &resp->fh))
+			return 0;
 	}
-	return xdr_ressize_check(rqstp, p);
+
+	return 1;
 }
 
 /* CREATE, MKDIR, SYMLINK, MKNOD */