void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address,
bool freeze, struct page *page);
-#if HPAGE_PMD_ORDER >= MAX_ORDER
-#error "hugepages can't be allocated by the buddy allocator"
-#endif
extern int hugepage_madvise(struct vm_area_struct *vma,
unsigned long *vm_flags, int advice);
extern void vma_adjust_trans_huge(struct vm_area_struct *vma,