/* write.c */
extern void nfs_write_prepare(struct rpc_task *task, void *calldata);
+#ifdef CONFIG_MIGRATION
+extern int nfs_migrate_page(struct address_space *,
+ struct page *, struct page *);
+#else
+#define nfs_migrate_page NULL
+#endif
/* nfs4proc.c */
extern int _nfs4_call_sync(struct nfs_server *server,