/*
   * This file is only for sharing some helpers from read_write.c with compat.c.
   * Don't use anywhere else.
   */
  
  
  typedef ssize_t (*io_fn_t)(struct file *, char __user *, size_t, loff_t *);
  typedef ssize_t (*iov_fn_t)(struct kiocb *, const struct iovec *,
  		unsigned long, loff_t);
  
  ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov,
  		unsigned long nr_segs, size_t len, loff_t *ppos, iov_fn_t fn);
  ssize_t do_loop_readv_writev(struct file *filp, struct iovec *iov,
  		unsigned long nr_segs, loff_t *ppos, io_fn_t fn);