x86_64/memory: fix scoped_mapping unmap logic

1 files changed, 13 insertions, 19 deletions

diff --git a/arch/x86_64/src/memory/scoped_mapping.cpp b/arch/x86_64/src/memory/scoped_mapping.cpp
index c9c6459..44dbf45 100644
--- a/arch/x86_64/src/memory/scoped_mapping.cpp
+++ b/arch/x86_64/src/memory/scoped_mapping.cpp
@@ -96,38 +96,32 @@ namespace teachos::memory::x86_64
       system::panic("[MEM] Tried to release an unmapped temporary mapping!");
     }
 
-    auto pml3 = paging_root::get().next(pml_index<4>(m_page)).value();
+    auto pml4 = &paging_root::get();
+    auto pml3 = pml4->next(pml_index<4>(m_page)).value();
     auto pml2 = pml3->next(pml_index<3>(m_page)).value();
     auto pml1 = pml2->next(pml_index<2>(m_page)).value();
 
+    (*pml1)[pml_index<1>(m_page)].clear();
+
     if (m_allocated & 1uz << 0)
     {
-      auto pml1_entry = (*pml1)[pml_index<1>(m_page)];
-      (*pml1)[pml_index<1>(m_page)].clear();
-      if (pml1->empty())
-      {
-        m_allocator->release(pml1_entry.frame().value());
-      }
+      auto pml1_frame = (*pml2)[pml_index<2>(m_page)].frame().value();
+      m_allocator->release(pml1_frame);
+      (*pml2)[pml_index<2>(m_page)].clear();
     }
 
     if (m_allocated & 1uz << 1)
     {
-      auto pml2_entry = (*pml2)[pml_index<2>(m_page)];
-      (*pml2)[pml_index<2>(m_page)].clear();
-      if (pml2->empty())
-      {
-        m_allocator->release(pml2_entry.frame().value());
-      }
+      auto pml2_frame = (*pml3)[pml_index<3>(m_page)].frame().value();
+      m_allocator->release(pml2_frame);
+      (*pml3)[pml_index<3>(m_page)].clear();
     }
 
     if (m_allocated & 1uz << 2)
     {
-      auto pml3_entry = (*pml3)[pml_index<3>(m_page)];
-      (*pml3)[pml_index<3>(m_page)].clear();
-      if (pml3->empty())
-      {
-        m_allocator->release(pml3_entry.frame().value());
-      }
+      auto pml3_frame = (*pml4)[pml_index<4>(m_page)].frame().value();
+      m_allocator->release(pml3_frame);
+      (*pml4)[pml_index<4>(m_page)].clear();
     }
 
     m_mapped = false;