IN_PROGRESS implement gdt initialization

8 files changed, 111 insertions, 13 deletions

diff --git a/arch/x86_64/include/arch/context_switching/descriptor_table/global_descriptor_table.hpp b/arch/x86_64/include/arch/context_switching/descriptor_table/global_descriptor_table.hpp
index e69de29..daba1fe 100644
--- a/arch/x86_64/include/arch/context_switching/descriptor_table/global_descriptor_table.hpp
+++ b/arch/x86_64/include/arch/context_switching/descriptor_table/global_descriptor_table.hpp
@@ -0,0 +1,19 @@
+#ifndef TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_DESCRIPTOR_TABLE_GLOBAL_DESCRIPTOR_TABLE_HPP
+#define TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_DESCRIPTOR_TABLE_GLOBAL_DESCRIPTOR_TABLE_HPP
+
+#include "arch/context_switching/descriptor_table/global_descriptor_table_pointer.hpp"
+#include "arch/context_switching/descriptor_table/segment_descriptor.hpp"
+#include "arch/stl/vector.hpp"
+
+namespace teachos::arch::context_switching::descriptor_table
+{
+  typedef stl::vector<segment_descriptor> global_descriptor_table;
+
+  auto create_global_descriptor_table() -> global_descriptor_table;
+
+  auto load_global_descriptor_table(global_descriptor_table_pointer gdt_pointer) -> void;
+
+  auto initialize_global_descriptor_table() -> global_descriptor_table;
+}  // namespace teachos::arch::context_switching::descriptor_table
+
+#endif  // TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_DESCRIPTOR_TABLE_GLOBAL_DESCRIPTOR_TABLE_HPP
diff --git a/arch/x86_64/include/arch/context_switching/descriptor_table/global_descriptor_table_pointer.hpp b/arch/x86_64/include/arch/context_switching/descriptor_table/global_descriptor_table_pointer.hpp
new file mode 100644
index 0000000..c2925fd
--- /dev/null
+++ b/arch/x86_64/include/arch/context_switching/descriptor_table/global_descriptor_table_pointer.hpp
@@ -0,0 +1,23 @@
+#ifndef TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_DESCRIPTOR_TABLE_GLOBAL_DESCRIPTOR_TABLE_POINTER_HPP
+#define TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_DESCRIPTOR_TABLE_GLOBAL_DESCRIPTOR_TABLE_POINTER_HPP
+
+#include "arch/context_switching/descriptor_table/global_descriptor_table.hpp"
+
+#include <cstdint>
+
+namespace teachos::arch::context_switching::descriptor_table
+{
+  /**
+   * @brief Represents a pointer to the Global Descriptor Table (GDT).
+   *
+   * This structure is used to store the base address and length of the GDT.
+   * It is used when loading or modifying the GDT during context switching.
+   */
+  struct global_descriptor_table_pointer
+  {
+    uint16_t table_length;              ///< The size of the GDT in bytes.
+    global_descriptor_table * address;  ///< Pointer to the GDT base address.
+  };
+}  // namespace teachos::arch::context_switching::descriptor_table
+
+#endif  // TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_DESCRIPTOR_TABLE_GLOBAL_DESCRIPTOR_TABLE_POINTER_HPP
diff --git a/arch/x86_64/include/arch/memory/cpu/control_register.hpp b/arch/x86_64/include/arch/kernel/cpu/control_register.hpp
index e11813d..27c7777 100644
--- a/arch/x86_64/include/arch/memory/cpu/control_register.hpp
+++ b/arch/x86_64/include/arch/kernel/cpu/control_register.hpp
@@ -1,5 +1,5 @@
-#ifndef TEACHOS_ARCH_X86_64_MEMORY_CPU_CR3_HPP
-#define TEACHOS_ARCH_X86_64_MEMORY_CPU_CR3_HPP
+#ifndef TEACHOS_ARCH_X86_64_KERNEL_CPU_CR3_HPP
+#define TEACHOS_ARCH_X86_64_KERNEL_CPU_CR3_HPP
 
 #include <cstdint>
 
@@ -68,4 +68,4 @@ namespace teachos::arch::memory::cpu
 
 }  // namespace teachos::arch::memory::cpu
 
-#endif  // TEACHOS_ARCH_X86_64_MEMORY_CPU_CR3_HPP
+#endif  // TEACHOS_ARCH_X86_64_KERNEL_CPU_CR3_HPP
diff --git a/arch/x86_64/include/arch/memory/cpu/msr.hpp b/arch/x86_64/include/arch/kernel/cpu/msr.hpp
index cda70e2..52d74bd 100644
--- a/arch/x86_64/include/arch/memory/cpu/msr.hpp
+++ b/arch/x86_64/include/arch/kernel/cpu/msr.hpp
@@ -1,5 +1,5 @@
-#ifndef TEACHOS_ARCH_X86_64_MEMORY_CPU_NXE_HPP
-#define TEACHOS_ARCH_X86_64_MEMORY_CPU_NXE_HPP
+#ifndef TEACHOS_ARCH_X86_64_KERNEL_CPU_NXE_HPP
+#define TEACHOS_ARCH_X86_64_KERNEL_CPU_NXE_HPP
 
 #include <bitset>
 #include <cstdint>
@@ -61,4 +61,4 @@ namespace teachos::arch::memory::cpu
 
 }  // namespace teachos::arch::memory::cpu
 
-#endif  // TEACHOS_ARCH_X86_64_MEMORY_CPU_NXE_HPP
\ No newline at end of file
+#endif  // TEACHOS_ARCH_X86_64_KERNEL_CPU_NXE_HPP
\ No newline at end of file
diff --git a/arch/x86_64/include/arch/kernel/cpu/ss.hpp b/arch/x86_64/include/arch/kernel/cpu/ss.hpp
new file mode 100644
index 0000000..2d3518e
--- /dev/null
+++ b/arch/x86_64/include/arch/kernel/cpu/ss.hpp
@@ -0,0 +1,56 @@
+#ifndef TEACHOS_ARCH_X86_64_KERNEL_CPU_SS_HPP
+#define TEACHOS_ARCH_X86_64_KERNEL_CPU_SS_HPP
+
+#include <bitset>
+#include <cstdint>
+
+namespace teachos::arch::memory::cpu
+{
+  /**
+   * @brief Represents a segment selector in the x86_64 architecture.
+   *
+   * A segment selector is a 16-bit identifier used to select a segment descriptor
+   * from the Global Descriptor Table (GDT) or the Local Descriptor Table (LDT).
+   * It contains an index, a table indicator (TI), and a requested privilege level (RPL).
+   */
+  struct segment_selector
+  {
+    /**
+     * @brief Constructs a segment selector.
+     *
+     * @param index The index of the segment descriptor.
+     * @param table_indicator The table indicator (0 for GDT, 1 for LDT).
+     * @param requested_privilege_level The requested privilege level (0-3).
+     */
+    segment_selector(uint16_t index, std::bitset<1U> table_indicator, std::bitset<2U> requested_privilege_level);
+
+    /**
+     * @brief Converts the segment selector to a 16-bit value.
+     *
+     * @return uint16_t The 16-bit representation of the segment selector.
+     */
+    auto to_uint16() const -> uint16_t;
+
+  private:
+    uint16_t index;
+    std::bitset<1U> table_indicator;
+    std::bitset<2U> requested_privilege_level;
+  };
+
+  /**
+   * @brief Reads the current value of the stack segment (SS) register.
+   *
+   * @return uint16_t The current SS register value.
+   */
+  auto read_ss() -> uint16_t;
+
+  /**
+   * @brief Writes a new value to the stack segment (SS) register.
+   *
+   * @param selector The segment selector to be written to SS.
+   */
+  auto write_ss(segment_selector selector) -> void;
+
+}  // namespace teachos::arch::memory::cpu
+
+#endif  // TEACHOS_ARCH_X86_64_KERNEL_CPU_SS_HPP
diff --git a/arch/x86_64/include/arch/memory/cpu/tlb.hpp b/arch/x86_64/include/arch/kernel/cpu/tlb.hpp
index 075d7bb..333cd58 100644
--- a/arch/x86_64/include/arch/memory/cpu/tlb.hpp
+++ b/arch/x86_64/include/arch/kernel/cpu/tlb.hpp
@@ -1,5 +1,5 @@
-#ifndef TEACHOS_ARCH_X86_64_MEMORY_CPU_TLB_HPP
-#define TEACHOS_ARCH_X86_64_MEMORY_CPU_TLB_HPP
+#ifndef TEACHOS_ARCH_X86_64_KERNEL_CPU_TLB_HPP
+#define TEACHOS_ARCH_X86_64_KERNEL_CPU_TLB_HPP
 
 #include "arch/memory/paging/virtual_page.hpp"
 
@@ -24,4 +24,4 @@ namespace teachos::arch::memory::cpu
 
 }  // namespace teachos::arch::memory::cpu
 
-#endif  // TEACHOS_ARCH_X86_64_MEMORY_CPU_TLB_HPP
+#endif  // TEACHOS_ARCH_X86_64_KERNEL_CPU_TLB_HPP
diff --git a/arch/x86_64/include/arch/memory/paging/active_page_table.hpp b/arch/x86_64/include/arch/memory/paging/active_page_table.hpp
index 1b2aaed..9846a21 100644
--- a/arch/x86_64/include/arch/memory/paging/active_page_table.hpp
+++ b/arch/x86_64/include/arch/memory/paging/active_page_table.hpp
@@ -2,8 +2,8 @@
 #define TEACHOS_ARCH_X86_64_MEMORY_PAGING_ACTIVE_PAGE_TABLE_HPP
 
 #include "arch/exception_handling/assert.hpp"
+#include "arch/kernel/cpu/tlb.hpp"
 #include "arch/memory/allocator/concept.hpp"
-#include "arch/memory/cpu/tlb.hpp"
 #include "arch/memory/paging/virtual_page.hpp"
 
 #include <array>
@@ -75,8 +75,8 @@ namespace teachos::arch::memory::paging
      * @param flags A bitset of flags that configure the page table entry for this mapping.
      */
     template<allocator::FrameAllocator T>
-    auto map_page_to_frame(T & allocator, virtual_page page, allocator::physical_frame frame,
-                           std::bitset<64U> flags) -> void
+    auto map_page_to_frame(T & allocator, virtual_page page, allocator::physical_frame frame, std::bitset<64U> flags)
+        -> void
     {
       auto current_handle = active_handle;
 
diff --git a/arch/x86_64/include/arch/memory/paging/kernel_mapper.hpp b/arch/x86_64/include/arch/memory/paging/kernel_mapper.hpp
index 74f1c14..b137736 100644
--- a/arch/x86_64/include/arch/memory/paging/kernel_mapper.hpp
+++ b/arch/x86_64/include/arch/memory/paging/kernel_mapper.hpp
@@ -1,7 +1,7 @@
 #ifndef TEACHOS_ARCH_X86_64_MEMORY_PAGING_KERNEL_MAPPER_HPP
 #define TEACHOS_ARCH_X86_64_MEMORY_PAGING_KERNEL_MAPPER_HPP
 
-#include "arch/memory/cpu/control_register.hpp"
+#include "arch/kernel/cpu/control_register.hpp"
 #include "arch/memory/paging/active_page_table.hpp"
 #include "arch/memory/paging/inactive_page_table.hpp"
 #include "arch/memory/paging/temporary_page.hpp"