(defun replace-regexp-entire-buffer (pattern replacement)
  "Perform regular-expression replacement throughout buffer."
  (interactive
   (let ((args (query-replace-read-args "Replace" t)))
     (setcdr (cdr args) nil)    ; remove third value returned from query---args
     args))
  (save-excursion
    (goto-char (point-min))
    (while (re-search-forward pattern nil t)
      (replace-match replacement))))

(defun my/query-replace (from-string to-string &optional delimited start end)
  "Replace some occurrences of FROM-STRING with TO-STRING.  As each match is
found, the user must type a character saying what to do with it. This is a
modified version of the standard `query-replace' function in `replace.el',
This modified version defaults to operating on the entire buffer instead of
working only from POINT to the end of the buffer. For more information, see
the documentation of `query-replace'"
  (interactive
   (let ((common
      (query-replace-read-args
       (concat "Query replace"
           (if current-prefix-arg " word" "")
           (if (and transient-mark-mode mark-active) " in region" ""))
       nil)))
     (list (nth 0 common) (nth 1 common) (nth 2 common)
       (if (and transient-mark-mode mark-active)
           (region-beginning)
         (buffer-end -1))
       (if (and transient-mark-mode mark-active)
           (region-end)
         (buffer-end 1)))))
  (perform-replace from-string to-string t nil delimited nil nil start end))
;; Replace the default key mapping
(define-key esc-map "%" 'my/query-replace)

(defun my/query-replace-regexp (regexp to-string &optional delimited start end)
  "Replace some things after point matching REGEXP with TO-STRING.  As each
match is found, the user must type a character saying what to do with
it. This is a modified version of the standard `query-replace-regexp'
function in `replace.el', This modified version defaults to operating on the
entire buffer instead of working only from POINT to the end of the
buffer. For more information, see the documentation of `query-replace-regexp'"
  (interactive
   (let ((common
      (query-replace-read-args
       (concat "Query replace"
           (if current-prefix-arg " word" "")
           " regexp"
           (if (and transient-mark-mode mark-active) " in region" ""))
       t)))
     (list (nth 0 common) (nth 1 common) (nth 2 common)
       (if (and transient-mark-mode mark-active)
           (region-beginning)
         (buffer-end -1))
       (if (and transient-mark-mode mark-active)
           (region-end)
         (buffer-end 1)))))
  (perform-replace regexp to-string t t delimited nil nil start end))
;; Replace the default key mapping
(define-key esc-map [?C-%] 'my/query-replace-regexp)

(defun query-replace-from-top ()
  (interactive)
  (let ((orig-point (point)))
    (save-excursion
      (goto-char (point-min))
      (call-interactively 'query-replace))
    (message "Back to old point.")
    (goto-char orig-point)))
(bind-key* "M-%" 'query-replace-from-top)