continue implementing paging

2 files changed, 21 insertions, 27 deletions

diff --git a/arch/x86_64/src/memory/frame_allocator.cpp b/arch/x86_64/src/memory/frame_allocator.cpp
index 3733cc3..01dcc88 100644
--- a/arch/x86_64/src/memory/frame_allocator.cpp
+++ b/arch/x86_64/src/memory/frame_allocator.cpp
@@ -1,7 +1,11 @@
 #include "arch/memory/frame_allocator.hpp"
 
+#include "arch/exception_handling/assert.hpp"
+
 namespace teachos::arch::memory
 {
+  uint64_t PAGE_SIZE;
+
   physical_frame::physical_frame(std::size_t frame_number)
       : frame_number(frame_number)
   {
@@ -13,6 +17,8 @@ namespace teachos::arch::memory
     return physical_frame{address / PAGE_FRAME_SIZE};
   }
 
+  auto physical_frame::start_address() const -> uint64_t { return frame_number * PAGE_SIZE; }
+
   memory_area_iterator::memory_area_iterator(memory_area * p)
       : ptr(p)
   {
@@ -103,10 +109,8 @@ namespace teachos::arch::memory
 
   auto area_frame_allocator::deallocate_frame(physical_frame physical_frame) -> void
   {
-    // TODO: Fix, simply done because compiler will complain if physical_frame is unused and not compile
-    if (physical_frame.frame_number == 3)
-    {
-    }
+    arch::exception_handling::assert(false && physical_frame.frame_number == 0,
+                                     "[deallocate_frame] Not implemented Exception");
   }
 
   auto area_frame_allocator::begin() -> memory_area_iterator { return area_begin; }
diff --git a/arch/x86_64/src/memory/paging.cpp b/arch/x86_64/src/memory/paging.cpp
index 555357c..90c4199 100644
--- a/arch/x86_64/src/memory/paging.cpp
+++ b/arch/x86_64/src/memory/paging.cpp
@@ -1,34 +1,16 @@
 #include "arch/memory/paging.hpp"
 
+#include "arch/exception_handling/assert.hpp"
+
 namespace teachos::arch::memory
 {
   auto entry::is_unused() const -> bool { return flags == 0U; }
 
   auto entry::set_unused() -> void { flags = 0U; }
 
-  auto entry::present() const -> bool { return is_bit_set(0U); }
-
-  auto entry::writable() const -> bool { return is_bit_set(1U); }
-
-  auto entry::user_accessible() const -> bool { return is_bit_set(2U); }
-
-  auto entry::write_through_caching() const -> bool { return is_bit_set(3U); }
-
-  auto entry::disabled_caching() const -> bool { return is_bit_set(4U); }
-
-  auto entry::is_accessing() const -> bool { return is_bit_set(5U); }
-
-  auto entry::is_diry() const -> bool { return is_bit_set(6U); }
-
-  auto entry::is_huge_page() const -> bool { return is_bit_set(7U); }
-
-  auto entry::is_global() const -> bool { return is_bit_set(8U); }
-
-  auto entry::executing_code_forbidden() const -> bool { return is_bit_set(63U); }
-
   auto entry::calculate_pointed_to_frame() const -> std::optional<physical_frame>
   {
-    if (present())
+    if (contains_flags(1))
     {
       auto physical_address = calculate_physical_address();
       return physical_frame::containing_address(physical_address);
@@ -39,7 +21,7 @@ namespace teachos::arch::memory
   auto entry::calculate_physical_address() const -> std::size_t
   {
     constexpr std::size_t start_bit = 12U;
-    constexpr std::size_t end_bit = 51U;
+    constexpr std::size_t end_bit = 52U;
     size_t value = 0U;
 
     for (auto i = start_bit; i < end_bit; i++)
@@ -49,5 +31,13 @@ namespace teachos::arch::memory
     return value;
   }
 
-  auto entry::is_bit_set(uint8_t index) const -> bool { return flags[index] == 1U; }
+  auto entry::set(physical_frame frame) -> void
+  {
+    arch::exception_handling::assert((frame.start_address() & ~0x000fffff'fffff000) == 0,
+                                     "Start address is not aligned with Page");
+    flags = std::bitset<64U>(frame.start_address()) | flags;
+  }
+
+  auto entry::contains_flags(std::bitset<64U> b) const -> bool { return (flags & b) == b; }
+
 }  // namespace teachos::arch::memory