Move page_is_ram() declaration to mm.h

Move page_is_ram() declaration to mm.h, it makes no sense in <linux/ioport.h>.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
LKML-Reference: <20100127030639.GD8132@localhost>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

include/linux/mm.h

@@ -265,6 +265,8 @@ static inline int get_page_unless_zero(struct page *page)
 	return atomic_inc_not_zero(&page->_count);
 }
 
+extern int page_is_ram(unsigned long pfn);
+
 /* Support for virtually mapped pages */
 struct page *vmalloc_to_page(const void *addr);
 unsigned long vmalloc_to_pfn(const void *addr);