Make sure the mmap callback is set to NULL in the deferred io
cleanup function. This way we can enable and disable deferred
io on the fly.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: Jaya Kumar <jayakumar.lkml@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
                page = vmalloc_to_page(screen_base + i);
                page->mapping = NULL;
        }
+
+       info->fbops->fb_mmap = NULL;
+       mutex_destroy(&fbdefio->lock);
 }
 EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup);