NFSD: Clean up nfsd4_encode_entry4()

Reshape nfsd4_encode_entry4() to be more like the legacy dirent
encoders, which were recently rewritten to use xdr_stream.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

fs/nfsd/nfs4xdr.c

@@ -3772,7 +3772,6 @@ nfsd4_encode_entry4(void *ccdv, const char *name, int namlen,
 	u32 name_and_cookie;
 	int entry_bytes;
 	__be32 nfserr = nfserr_toosmall;
-	__be32 *p;
 
 	/* In nfsv4, "." and ".." never make it onto the wire.. */
 	if (name && isdotent(name, namlen)) {
@@ -3783,17 +3782,15 @@ nfsd4_encode_entry4(void *ccdv, const char *name, int namlen,
 	/* Encode the previous entry's cookie value */
 	nfsd4_encode_entry4_nfs_cookie4(cd, offset);
 
-	p = xdr_reserve_space(xdr, 4);
-	if (!p)
+	if (xdr_stream_encode_item_present(xdr) != XDR_UNIT)
 		goto fail;
-	*p++ = xdr_one;                             /* mark entry present */
+
+	/* Reserve send buffer space for this entry's cookie value. */
 	cookie_offset = xdr->buf->len;
-	p = xdr_reserve_space(xdr, 3*4 + namlen);
-	if (!p)
+	if (nfsd4_encode_nfs_cookie4(xdr, OFFSET_MAX) != nfs_ok)
+		goto fail;
+	if (nfsd4_encode_component4(xdr, name, namlen) != nfs_ok)
 		goto fail;
-	p = xdr_encode_hyper(p, OFFSET_MAX);        /* offset of next entry */
-	p = xdr_encode_array(p, name, namlen);      /* name length & name */
-
 	nfserr = nfsd4_encode_entry4_fattr(cd, name, namlen);
 	switch (nfserr) {
 	case nfs_ok:

fs/nfsd/xdr4.h

@@ -120,6 +120,7 @@ nfsd4_encode_uint64_t(struct xdr_stream *xdr, u64 val)
 }
 
 #define nfsd4_encode_changeid4(x, v)	nfsd4_encode_uint64_t(x, v)
+#define nfsd4_encode_nfs_cookie4(x, v)	nfsd4_encode_uint64_t(x, v)
 #define nfsd4_encode_length4(x, v)	nfsd4_encode_uint64_t(x, v)
 #define nfsd4_encode_offset4(x, v)	nfsd4_encode_uint64_t(x, v)
 
@@ -174,6 +175,8 @@ nfsd4_encode_opaque(struct xdr_stream *xdr, const void *data, size_t size)
 	return nfs_ok;
 }
 
+#define nfsd4_encode_component4(x, d, s)	nfsd4_encode_opaque(x, d, s)
+
 struct nfsd4_compound_state {
 	struct svc_fh		current_fh;
 	struct svc_fh		save_fh;