+void
+region_release(struct mm_region* region);
+
+void
+region_release_all(vm_regions_t* lead);
+
+struct mm_region*
+region_get(vm_regions_t* lead, unsigned long vaddr);
+
+void
+region_copy_mm(struct proc_mm* src, struct proc_mm* dest);
+
+struct mm_region*
+region_dup(struct mm_region* origin);