Finish implementing 8-byte GDT entries and syscall arg loads.

6 files changed, 98 insertions, 110 deletions

diff --git a/arch/x86_64/include/arch/context_switching/interrupt_descriptor_table/segment_selector.hpp b/arch/x86_64/include/arch/context_switching/interrupt_descriptor_table/segment_selector.hpp
index 8748448..5be449f 100644
--- a/arch/x86_64/include/arch/context_switching/interrupt_descriptor_table/segment_selector.hpp
+++ b/arch/x86_64/include/arch/context_switching/interrupt_descriptor_table/segment_selector.hpp
@@ -79,11 +79,11 @@ namespace teachos::arch::context_switching::interrupt_descriptor_table
     auto operator|=(std::bitset<3U> other) -> void;
 
     /**
-     * @brief Combines all bits in the underlying data in the correct order to return a raw value containing all bits.
+     * @brief Cast the underlying data into a combined 16-bit form, that contains all data.
      *
      * @return Underlying value combined into it's full size.
      */
-    operator uint16_t() const { return static_cast<uint64_t>(_flags) | (static_cast<uint64_t>(_index) << 3U); }
+    operator uint16_t() const;
 
   private:
     uint8_t _flags : 3 = {};  ///< Underlying bits used to read the flags from.
diff --git a/arch/x86_64/include/arch/context_switching/segment_descriptor_table/global_descriptor_table.hpp b/arch/x86_64/include/arch/context_switching/segment_descriptor_table/global_descriptor_table.hpp
index 84a24a2..44f2692 100644
--- a/arch/x86_64/include/arch/context_switching/segment_descriptor_table/global_descriptor_table.hpp
+++ b/arch/x86_64/include/arch/context_switching/segment_descriptor_table/global_descriptor_table.hpp
@@ -30,7 +30,7 @@ namespace teachos::arch::context_switching::segment_descriptor_table
    * @note This method should only be called after update_gdtr() and a far jump has been
    * executed. Because before that trying to access the segment will cause an exception.
    */
-  auto update_task_state_segment_register() -> void;
+  auto update_tss_register() -> void;
 
 }  // namespace teachos::arch::context_switching::segment_descriptor_table
 
diff --git a/arch/x86_64/include/arch/context_switching/segment_descriptor_table/global_descriptor_table_pointer.hpp b/arch/x86_64/include/arch/context_switching/segment_descriptor_table/global_descriptor_table_pointer.hpp
index c54647d..292ff70 100644
--- a/arch/x86_64/include/arch/context_switching/segment_descriptor_table/global_descriptor_table_pointer.hpp
+++ b/arch/x86_64/include/arch/context_switching/segment_descriptor_table/global_descriptor_table_pointer.hpp
@@ -1,24 +1,13 @@
 #ifndef TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_SEGMENT_DESCRIPTOR_TABLE_GLOBAL_DESCRIPTOR_TABLE_POINTER_HPP
 #define TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_SEGMENT_DESCRIPTOR_TABLE_GLOBAL_DESCRIPTOR_TABLE_POINTER_HPP
 
-#include "arch/context_switching/segment_descriptor_table/segment_descriptor_base.hpp"
-#include "arch/context_switching/segment_descriptor_table/segment_descriptor_extension.hpp"
 #include "arch/stl/vector.hpp"
 
 #include <cstdint>
 
 namespace teachos::arch::context_switching::segment_descriptor_table
 {
-  struct __attribute__((packed, aligned(8))) global_descriptor_table
-  {
-    segment_descriptor_base null;
-    segment_descriptor_base kernel_code;
-    segment_descriptor_base kernel_data;
-    segment_descriptor_base user_code;
-    segment_descriptor_base user_data;
-    segment_descriptor_base tss_low;
-    segment_descriptor_extension tss_high;
-  };
+  using global_descriptor_table = stl::vector<uint64_t>;
 
   /**
    * @brief Represents a pointer to the Global Descriptor Table (GDT).
@@ -36,7 +25,7 @@ namespace teachos::arch::context_switching::segment_descriptor_table
     /**
      * @brief Constructor.
      */
-    global_descriptor_table_pointer(uint16_t table_length, seg_desc * address);
+    global_descriptor_table_pointer(uint16_t table_length, uint64_t * address);
 
     /**
      * @brief Defaulted three-way comparsion operator.
@@ -45,7 +34,7 @@ namespace teachos::arch::context_switching::segment_descriptor_table
 
   private:
     uint16_t table_length = {};  ///< The amount of segment descriptor entries in the global descriptor table - 1.
-    seg_desc * address = {};     ///< Non-owning pointer to the GDT base address.
+    uint64_t * address = {};     ///< Non-owning pointer to the GDT base address.
   };
 }  // namespace teachos::arch::context_switching::segment_descriptor_table
 
diff --git a/arch/x86_64/include/arch/context_switching/segment_descriptor_table/segment_descriptor.hpp b/arch/x86_64/include/arch/context_switching/segment_descriptor_table/segment_descriptor.hpp
deleted file mode 100644
index ccd604d..0000000
--- a/arch/x86_64/include/arch/context_switching/segment_descriptor_table/segment_descriptor.hpp
+++ /dev/null
@@ -1,83 +0,0 @@
-#ifndef TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_SEGMENT_DESCRIPTOR_TABLE_SEGMENT_DESCRIPTOR_HPP
-#define TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_SEGMENT_DESCRIPTOR_TABLE_SEGMENT_DESCRIPTOR_HPP
-
-#include "arch/context_switching/segment_descriptor_table/access_byte.hpp"
-#include "arch/context_switching/segment_descriptor_table/gdt_flags.hpp"
-#include "arch/context_switching/segment_descriptor_table/segment_descriptor_type.hpp"
-
-namespace teachos::arch::context_switching::segment_descriptor_table
-{
-  __extension__ typedef __int128 int128_t;
-  __extension__ typedef unsigned __int128 uint128_t;
-
-  struct seg_desc
-  {
-  private:
-    uint64_t : 64;  ///< Makes sure the struct is 8-Bytes big
-  };
-
-  /**
-   * @brief Defines helper function for all states and the actual data the segment descriptor can have.
-   */
-  struct [[gnu::packed]] segment_descriptor
-  {
-    /**
-     * @brief Default Constructor.
-     */
-    segment_descriptor() = default;
-
-    /**
-     * @brief Constructor.
-     *
-     * @note Created segment descriptor copies the given bytes into theese components ending with a 32 bit reserved
-     * field that has to be used, because the 64-bit segment descriptor needs to be big enough for two 32-bit segment
-     * descriptor.
-     * - 8 bit Access Type
-     * - 4 bit Flags
-     * - 64 bit Base Address
-     * - 20 bit Limit
-     *
-     * @param flags Copies the bits set from the given data into the individual components of a segment
-     * descriptor.
-     */
-    explicit segment_descriptor(uint128_t flags);
-
-    /**
-     * @brief Constructor.
-     *
-     * @param access_byte, flags, base, limit Copies the bits set from the given data into the individual components of
-     * a segment descriptor.
-     */
-    segment_descriptor(access_byte access_byte, gdt_flags flags, uint64_t base, std::bitset<20U> limit);
-
-    auto get_limit_1() -> uint16_t;
-    auto get_base_1() -> uint32_t;
-    auto get_access() -> access_byte;
-    auto get_flag() -> gdt_flags;
-    auto get_base_2() -> uint64_t;
-
-    /**
-     * @brief Calculates the underlying segment type that this segement descriptor is describing.
-     */
-    auto get_segment_type() const -> segment_descriptor_type;
-
-    /**
-     * @brief Allows to compare the underlying bits of two instances.
-     *
-     * @param other Other instance that we want to compare with.
-     * @return Whether the underlying set bits of both types are the same.
-     */
-    auto operator==(segment_descriptor const & other) const -> bool = default;
-
-  private:
-    // The order in private variables starts for the first variable being the rightmost bit.
-    uint16_t _limit_1 = {};      ///< First part of the limit field (0 - 15)
-    uint32_t _base_1 : 24 = {};  ///< First part of the base field (16 - 39)
-    access_byte _access = {};    ///< Access byte field (40 - 47)
-    gdt_flags _flag = {};        ///< Second part of the limit field + Flags field (48 - 55)
-    uint64_t _base_2 : 40 = {};  ///< Second part of the base field (56 - 95)
-    uint32_t : 32;               ///< Reserved field used to ensure this struct is 128 bits big (96 - 127)
-  };
-}  // namespace teachos::arch::context_switching::segment_descriptor_table
-
-#endif  // TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_SEGMENT_DESCRIPTOR_TABLE_SEGMENT_DESCRIPTOR_HPP
diff --git a/arch/x86_64/include/arch/context_switching/segment_descriptor_table/segment_descriptor_base.hpp b/arch/x86_64/include/arch/context_switching/segment_descriptor_table/segment_descriptor_base.hpp
index 18c9da1..933fb4d 100644
--- a/arch/x86_64/include/arch/context_switching/segment_descriptor_table/segment_descriptor_base.hpp
+++ b/arch/x86_64/include/arch/context_switching/segment_descriptor_table/segment_descriptor_base.hpp
@@ -3,7 +3,6 @@
 
 #include "arch/context_switching/segment_descriptor_table/access_byte.hpp"
 #include "arch/context_switching/segment_descriptor_table/gdt_flags.hpp"
-#include "arch/context_switching/segment_descriptor_table/segment_descriptor.hpp"
 #include "arch/context_switching/segment_descriptor_table/segment_descriptor_type.hpp"
 
 namespace teachos::arch::context_switching::segment_descriptor_table
@@ -11,7 +10,7 @@ namespace teachos::arch::context_switching::segment_descriptor_table
   /**
    * @brief Defines helper function for all states and the actual data the segment descriptor can have.
    */
-  struct [[gnu::packed]] segment_descriptor_base : seg_desc
+  struct [[gnu::packed]] segment_descriptor_base
   {
     /**
      * @brief Default Constructor.
@@ -20,14 +19,54 @@ namespace teachos::arch::context_switching::segment_descriptor_table
 
     /**
      * @brief Constructor.
+     *
+     * @note Created segment descriptor copies the given bytes into these components requiring the space of one
+     * segment descriptor entry in the global descriptor table being 64-bit.
+     * - 8 bit Access Type
+     * - 4 bit Flags
+     * - 32 bit Base Address
+     * - 20 bit Limit
+     *
+     * @param flags Copies the bits set from the given data into the individual components of a segment
+     * descriptor.
      */
-    segment_descriptor_base(segment_descriptor segment_descriptor);
+    explicit segment_descriptor_base(uint64_t flags);
+
+    /**
+     * @brief Constructor.
+     *
+     * @param access_byte, flags, base, limit Copies the bits set from the given data into the individual components of
+     * a segment descriptor.
+     */
+    segment_descriptor_base(access_byte access_byte, gdt_flags flags, uint32_t base, std::bitset<20U> limit);
+
+    /**
+     * @brief Calculates the underlying segment type that this segement descriptor is describing.
+     */
+    auto get_segment_type() const -> segment_descriptor_type;
+
+    /**
+     * @brief Cast the underlying data into a combined 64-bit form, that contains all data.
+     *
+     * @return Underlying value combined into it's full size.
+     */
+    operator uint64_t() const;
+
+    /**
+     * @brief Allows to compare the underlying bits of two instances.
+     *
+     * @param other Other instance that we want to compare with.
+     * @return Whether the underlying set bits of both types are the same.
+     */
+    auto operator==(segment_descriptor_base const & other) const -> bool = default;
 
   private:
+    // The order in private variables starts for the first variable being the rightmost bit.
     uint16_t _limit_1 = {};      ///< First part of the limit field (0 - 15)
     uint32_t _base_1 : 24 = {};  ///< First part of the base field (16 - 39)
     access_byte _access = {};    ///< Access byte field (40 - 47)
     gdt_flags _flag = {};        ///< Second part of the limit field + Flags field (48 - 55)
+    uint8_t _base_2 = {};        ///< Second part of the base field (56 - 63)
   };
 }  // namespace teachos::arch::context_switching::segment_descriptor_table
 
diff --git a/arch/x86_64/include/arch/context_switching/segment_descriptor_table/segment_descriptor_extension.hpp b/arch/x86_64/include/arch/context_switching/segment_descriptor_table/segment_descriptor_extension.hpp
index 0b724f2..40bcc8a 100644
--- a/arch/x86_64/include/arch/context_switching/segment_descriptor_table/segment_descriptor_extension.hpp
+++ b/arch/x86_64/include/arch/context_switching/segment_descriptor_table/segment_descriptor_extension.hpp
@@ -1,16 +1,17 @@
 #ifndef TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_SEGMENT_DESCRIPTOR_TABLE_SEGMENT_DESCRIPTOR_EXTENSION_HPP
 #define TEACHOS_ARCH_X86_64_CONTEXT_SWITCHING_SEGMENT_DESCRIPTOR_TABLE_SEGMENT_DESCRIPTOR_EXTENSION_HPP
 
-#include "arch/context_switching/segment_descriptor_table/segment_descriptor.hpp"
-
-#include <cstdint>
+#include "arch/context_switching/segment_descriptor_table/segment_descriptor_base.hpp"
 
 namespace teachos::arch::context_switching::segment_descriptor_table
 {
+  __extension__ typedef __int128 int128_t;
+  __extension__ typedef unsigned __int128 uint128_t;
+
   /**
    * @brief Defines helper function for all states and the actual data the segment descriptor can have.
    */
-  struct [[gnu::packed]] segment_descriptor_extension : seg_desc
+  struct [[gnu::packed]] segment_descriptor_extension
   {
     /**
      * @brief Default Constructor.
@@ -19,12 +20,54 @@ namespace teachos::arch::context_switching::segment_descriptor_table
 
     /**
      * @brief Constructor.
+     *
+     * @note Created segment descriptor copies the given bytes into these components requiring the space of two
+     * segment descriptor entry in the global descriptor table being 128-bit. Ending with a 32 bit reserved
+     * field that has to be used, because the segment descriptor needs to be big enough for two segment
+     * descriptor entries.
+     * - 8 bit Access Type
+     * - 4 bit Flags
+     * - 64 bit Base Address
+     * - 20 bit Limit
+     *
+     * @param flags Copies the bits set from the given data into the individual components of a segment
+     * descriptor.
+     */
+    explicit segment_descriptor_extension(uint128_t flags);
+
+    /**
+     * @brief Constructor.
+     *
+     * @param access_byte, flags, base, limit Copies the bits set from the given data into the individual components of
+     * a segment descriptor.
+     */
+    segment_descriptor_extension(access_byte access_byte, gdt_flags flags, uint64_t base, std::bitset<20U> limit);
+
+    /**
+     * @brief Returns the underlying base segment descriptor, being the first part of the segment descriptor consisting
+     * of two entries in the global descriptor table.
+     */
+    auto get_first_gdt_entry() const -> segment_descriptor_base;
+
+    /**
+     * @brief Returns the underlying extension to the segment descriptor, being the second part of the segment
+     * descriptor consiting of two entries in the global descriptor table.
+     */
+    auto get_second_gdt_entry() const -> uint64_t;
+
+    /**
+     * @brief Allows to compare the underlying bits of two instances.
+     *
+     * @param other Other instance that we want to compare with.
+     * @return Whether the underlying set bits of both types are the same.
      */
-    segment_descriptor_extension(segment_descriptor segment_descriptor);
+    auto operator==(segment_descriptor_extension const & other) const -> bool = default;
 
   private:
-    uint64_t _base_2 : 40 = {};  ///< Second part of the base field (56 - 95)
-    uint32_t : 32;               ///< Reserved field used to ensure this struct is 128 bits big (96 - 127)
+    // The order in private variables starts for the first variable being the rightmost bit.
+    segment_descriptor_base _base = {};  ///< Base Segment Descriptor representing single entry in GDT (0 - 63)
+    uint32_t _base_3 = {};               ///< Third part of the base field (63 - 95)
+    uint32_t : 32;                       ///< Reserved field used to ensure this struct is 128 bits big (96 - 127)
   };
 }  // namespace teachos::arch::context_switching::segment_descriptor_table