void xen_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm);
void xen_exit_mmap(struct mm_struct *mm);
-void xen_pgd_pin(pgd_t *pgd);
-//void xen_pgd_unpin(pgd_t *pgd);
-
pteval_t xen_pte_val(pte_t);
pmdval_t xen_pmd_val(pmd_t);
pgdval_t xen_pgd_val(pgd_t);