Add RecursivePageTable as an owner for the P4 table

src/memory/paging/mod.rs

@@ -1,5 +1,7 @@
 pub use self::entry::*;
 use memory::{PAGE_SIZE, Frame, FrameAllocator};
+use self::table::{Table, Level4};
+use core::ptr::Unique;
 
 mod entry;
 mod table;
@@ -39,6 +41,24 @@ impl Page {
     }
 }
 
+pub struct RecursivePageTable {
+    p4: Unique<Table<Level4>>,
+}
+
+impl RecursivePageTable {
+    pub unsafe fn new() -> RecursivePageTable {
+        RecursivePageTable { p4: Unique::new(table::P4) }
+    }
+
+    fn p4(&self) -> &Table<Level4> {
+        unsafe { self.p4.get() }
+    }
+
+    fn p4_mut(&mut self) -> &mut Table<Level4> {
+        unsafe { self.p4.get_mut() }
+    }
+}
+
 pub unsafe fn translate(virtual_address: VirtualAddress) -> Option<PhysicalAddress> {
     let offset = virtual_address % PAGE_SIZE;
     translate_page(Page::containing_address(virtual_address))