Improve syscalls and user heap allocator

2 files changed, 23 insertions, 12 deletions

diff --git a/arch/x86_64/include/arch/memory/heap/user_heap_allocator.hpp b/arch/x86_64/include/arch/memory/heap/user_heap_allocator.hpp
index 42af23f..6b1b7bb 100644
--- a/arch/x86_64/include/arch/memory/heap/user_heap_allocator.hpp
+++ b/arch/x86_64/include/arch/memory/heap/user_heap_allocator.hpp
@@ -4,6 +4,8 @@
 #include "arch/memory/heap/memory_block.hpp"
 #include "arch/stl/mutex.hpp"
 
+#include <optional>
+
 namespace teachos::arch::memory::heap
 {
   /**
@@ -47,6 +49,19 @@ namespace teachos::arch::memory::heap
     [[gnu::section(".user_text")]] auto constexpr min_allocatable_size() -> std::size_t { return sizeof(memory_block); }
 
     /**
+     * @brief Checks if the given memory block is big enough and if it is allocates into the current block.
+     *
+     * @note Adjusts the link of the previous memory block to the new smaller remaining block. If the allocation used
+     * the complete block instead the previous block will point to the next block of the current memroy block that was
+     * used for the allocation.
+     *
+     * @return Allocated usable memory area.
+     */
+    [[gnu::section(".user_text")]] auto
+    allocate_into_memory_block_if_big_enough(memory_block * current, memory_block * previous, std::size_t total_size)
+        -> std::optional<void *>;
+
+    /**
      * @brief Special functionality fo the user heap allocator. Which will result in it being expanded by a syscall with
      * addtionally 100 KiB, which are mapped into the page table. Will always work until there is no physical memory
      * left.
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 977b40d..b211b8b 100644
--- a/arch/x86_64/include/arch/memory/paging/kernel_mapper.hpp
+++ b/arch/x86_64/include/arch/memory/paging/kernel_mapper.hpp
@@ -124,6 +124,13 @@ namespace teachos::arch::memory::paging
     auto map_elf_kernel_sections(active_page_table & active_table) -> void
     {
       exception_handling::assert(!mem_info.sections.empty(), "[Kernel Mapper] Kernel elf sections empty");
+      std::array<uint64_t, 6U> constexpr USER_SECTION_BASES = {
+          0x102000,  // .boot_bss (Contains statically allocated variables)
+          0x209000,  // .stl_text (Contains code for custom std implementations and standard library code)
+          0x218000,  // .user_text (Contains the actual user code executed)
+          0x21F000,  // .user_data (Contains static user variables)
+      };
+
       for (auto const & section : mem_info.sections)
       {
         if (!section.flags.contains_flags(multiboot::elf_section_flags::OCCUPIES_MEMORY))
@@ -144,18 +151,7 @@ namespace teachos::arch::memory::paging
         allocator::frame_container const frames{begin, end};
         entry entry{section.flags};
 
-        // Required to be accessible in User Mode:
-        constexpr std::array<uint64_t, 6> user_section_bases = {
-            0x102000,  // .boot_bss (Contains statically allocated variables)
-            0x209000,  // .stl_text (Contains code for custom std implementations and standard library code)
-            0x218000,  // .user_text (Contains the actual user code executed)
-            0x21E000,  // .user_data (Contains static user variables)
-
-            0x20A000  // .text (Necessary, because symbols for standard library are placed there)
-        };
-
-        if (std::find(user_section_bases.begin(), user_section_bases.end(), section.physical_address) !=
-            user_section_bases.end())
+        if (std::ranges::find(USER_SECTION_BASES, section.physical_address) != USER_SECTION_BASES.end())
         {
           entry.set_user_accessible();
         }