continue implementing paging

3 files changed, 43 insertions, 74 deletions

diff --git a/arch/x86_64/include/arch/exception_handling/assert.hpp b/arch/x86_64/include/arch/exception_handling/assert.hpp
new file mode 100644
index 0000000..eba43ac
--- /dev/null
+++ b/arch/x86_64/include/arch/exception_handling/assert.hpp
@@ -0,0 +1,11 @@
+namespace teachos::arch::exception_handling
+{
+  /**
+   * @brief assert a condition to be true, if not do not continue
+   * execution of the code and print message to screen
+   *
+   * @param condition
+   * @param message
+   */
+  auto assert(bool condition, char const * message) -> void;
+}  // namespace teachos::arch::exception_handling
\ No newline at end of file
diff --git a/arch/x86_64/include/arch/memory/frame_allocator.hpp b/arch/x86_64/include/arch/memory/frame_allocator.hpp
index ab93231..69c108c 100644
--- a/arch/x86_64/include/arch/memory/frame_allocator.hpp
+++ b/arch/x86_64/include/arch/memory/frame_allocator.hpp
@@ -32,6 +32,13 @@ namespace teachos::arch::memory
     static auto containing_address(std::size_t address) -> physical_frame;
 
     /**
+     * @brief  TODO
+     *
+     * @return uint64_t
+     */
+    auto start_address() const -> uint64_t;
+
+    /**
      * @brief Defaulted equals operator.
      */
     constexpr auto operator==(const physical_frame & other) const -> bool = default;
diff --git a/arch/x86_64/include/arch/memory/paging.hpp b/arch/x86_64/include/arch/memory/paging.hpp
index a5408e1..1870c28 100644
--- a/arch/x86_64/include/arch/memory/paging.hpp
+++ b/arch/x86_64/include/arch/memory/paging.hpp
@@ -43,72 +43,6 @@ namespace teachos::arch::memory
     auto set_unused() -> void;
 
     /**
-     * @brief Whether the current page is in memory and therefore present or not. Read from bit index 0.
-     *
-     * @return Current page is in memory.
-     */
-    auto present() const -> bool;
-
-    /**
-     * @brief Whether it is possible to write to the current page or not. Read from bit index 1.
-     *
-     * @return Current page can be written too.
-     */
-    auto writable() const -> bool;
-
-    /**
-     * @brief Whether the current page can be accessed in user mode, or only in kernel mode code. Read from bit index 2.
-     *
-     * @return Current page can be accessed in user mode.
-     */
-    auto user_accessible() const -> bool;
-
-    /**
-     * @brief Whether any write to the current page go directly to memory instead of the cache or not. Read from bit
-     * index 3.
-     *
-     * @return Writes to the current page go directly to memory.
-     */
-    auto write_through_caching() const -> bool;
-
-    /**
-     * @brief Whether the current page uses caching or not. Read from bit index 4.
-     *
-     * @return Current page does not use caching.
-     */
-    auto disabled_caching() const -> bool;
-
-    /**
-     * @brief Whether the current page is currently being used or not. Read from bit index 5.
-     *
-     * @return Current page is currently being used.
-     */
-    auto is_accessing() const -> bool;
-
-    /**
-     * @brief Whether the current page has been writen too or not. Read from bit index 6.
-     *
-     * @return Current page has been writen too.
-     */
-    auto is_diry() const -> bool;
-
-    /**
-     * @brief Whether the current page is huge or not (2 MiB page size in P2 page table and 1 GiB in P3 page table,
-     * instead of 4 KiB). Has to be false for P1 and P4 page tables. Read from bit index 7.
-     *
-     * @return Current page is huge
-     */
-    auto is_huge_page() const -> bool;
-
-    /**
-     * @brief Whether the current page is not flushed from caches on address space switches or not (PGE bit of CR4
-     * register has to be set). Read from bit index 8.
-     *
-     * @return Current page is not flushed from caches on address space switches.
-     */
-    auto is_global() const -> bool;
-
-    /**
      * @brief Whether the current page is forbidden from executing code or not (NXE bit in the EFER register has to be
      * set). Read from bit index 63.
      *
@@ -124,6 +58,22 @@ namespace teachos::arch::memory
      */
     auto calculate_pointed_to_frame() const -> std::optional<physical_frame>;
 
+    /**
+     * @brief TODO
+     *
+     * @param frame
+     */
+    auto set(physical_frame frame) -> void;
+
+    /**
+     * @brief TODO
+     *
+     * @param b
+     * @return true
+     * @return false
+     */
+    auto contains_flags(std::bitset<64U> b) const -> bool;
+
   private:
     /**
      * @brief Extracts the physical address from the underlying bitset read from bit index 12 - 51. Is a 52 bit page
@@ -134,17 +84,18 @@ namespace teachos::arch::memory
      */
     auto calculate_physical_address() const -> std::size_t;
 
-    /**
-     * @brief Checks the underlying std::bitset if the bit at the specific index is set, meaning a value of 1
-     *
-     * @param index Specific index we want to check at
-     * @return Bit value 1 is set and will return true
-     */
-    auto is_bit_set(uint8_t index) const -> bool;
-
     std::bitset<64U> flags;  ///< Underlying bitset used to read the flags from. Bits 9 - 11 and 52 - 62 can be freely
                              ///< used for additional flagsby the operating system.
   };
+
+  /**
+   * @brief TODO
+   *
+   */
+  struct page_table
+  {
+    entry entries[PAGE_TABLE_ENTRY_COUNT];
+  };
 }  // namespace teachos::arch::memory
 
 #endif  // TEACHOS_ARCH_X86_64_MEMORY_PAGING_HPP