vt: remove lines parameter from scrollback

It is always called with 0, so remove the parameter and pass the
default down to scrolldelta without checking.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/vt/keyboard.c

@@ -579,7 +579,7 @@ static void fn_scroll_forw(struct vc_data *vc)
 
 static void fn_scroll_back(struct vc_data *vc)
 {
-	scrollback(vc, 0);
+	scrollback(vc);
 }
 
 static void fn_show_mem(struct vc_data *vc)

drivers/tty/vt/vt.c

@@ -1102,11 +1102,9 @@ static void gotoxay(struct vc_data *vc, int new_x, int new_y)
 	gotoxy(vc, new_x, vc->vc_decom ? (vc->vc_top + new_y) : new_y);
 }
 
-void scrollback(struct vc_data *vc, int lines)
+void scrollback(struct vc_data *vc)
 {
-	if (!lines)
-		lines = vc->vc_rows / 2;
-	scrolldelta(-lines);
+	scrolldelta(-(vc->vc_rows / 2));
 }
 
 void scrollfront(struct vc_data *vc, int lines)

include/linux/vt_kern.h

@@ -45,7 +45,7 @@ void poke_blanked_console(void);
 int con_font_op(struct vc_data *vc, struct console_font_op *op);
 int con_set_cmap(unsigned char __user *cmap);
 int con_get_cmap(unsigned char __user *cmap);
-void scrollback(struct vc_data *vc, int lines);
+void scrollback(struct vc_data *vc);
 void scrollfront(struct vc_data *vc, int lines);
 void clear_buffer_attributes(struct vc_data *vc);
 void update_region(struct vc_data *vc, unsigned long start, int count);