feat: vspace: table: allow to get table vaddr

kernel/src/arch/riscv/vspace/table.rs

@@ -11,6 +11,10 @@ impl<'a, T: TableLevel> TableOps<'a, T> for Table<'a, T> {
         }
     }
 
+    fn vaddr(&self) -> VirtAddr {
+        VirtAddr::from(self.entries.as_ptr())
+    }
+
     fn map(&mut self, from: VirtAddr, to: PhysAddr, attr: MapAttr) -> PageResult {
         if !from.is_aligned(T::LEVEL_SIZE) || !to.is_aligned(PAGE_SIZE) {
             return Err(PageError::NotAligned);

kernel/src/vspace/table.rs

@@ -5,6 +5,7 @@ pub trait TableOps<'a, T: TableLevel> {
     /// # Safety
     /// `location` must be a page-aligned virtual address and will not be dropped.
     unsafe fn new(location: VirtAddr) -> Self;
+    fn vaddr(&self) -> VirtAddr;
 
     // following methods only works at current level