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| author | Felix Morgner <felix.morgner@ost.ch> | 2026-01-16 13:36:38 +0100 |
|---|---|---|
| committer | Felix Morgner <felix.morgner@ost.ch> | 2026-01-16 13:36:38 +0100 |
| commit | 7d6f0ed063790042a808f4bf07c50d308b3f2de4 (patch) | |
| tree | 1a2e1c4ed7e2f3d8e6cdcfb012e554d1a4eb1e5a /arch/x86_64/src/kapi/memory.cpp | |
| parent | 9750405757396d006ab6992fb93baf414b3e2ae8 (diff) | |
| download | teachos-7d6f0ed063790042a808f4bf07c50d308b3f2de4.tar.xz teachos-7d6f0ed063790042a808f4bf07c50d308b3f2de4.zip | |
chore: restructure namespaces
Diffstat (limited to 'arch/x86_64/src/kapi/memory.cpp')
| -rw-r--r-- | arch/x86_64/src/kapi/memory.cpp | 192 |
1 files changed, 0 insertions, 192 deletions
diff --git a/arch/x86_64/src/kapi/memory.cpp b/arch/x86_64/src/kapi/memory.cpp deleted file mode 100644 index e2681a6..0000000 --- a/arch/x86_64/src/kapi/memory.cpp +++ /dev/null @@ -1,192 +0,0 @@ -#include "kapi/memory.hpp" - -#include "kapi/boot.hpp" -#include "kapi/system.hpp" - -#include "x86_64/boot/boot.hpp" -#include "x86_64/boot/ld.hpp" -#include "x86_64/cpu/registers.hpp" -#include "x86_64/memory/buffered_allocator.hpp" -#include "x86_64/memory/kernel_mapper.hpp" -#include "x86_64/memory/mmu.hpp" -#include "x86_64/memory/page_table.hpp" -#include "x86_64/memory/page_utilities.hpp" -#include "x86_64/memory/paging_root.hpp" -#include "x86_64/memory/recursive_page_mapper.hpp" -#include "x86_64/memory/region_allocator.hpp" -#include "x86_64/memory/scoped_mapping.hpp" - -#include <kstd/print> - -#include <multiboot2/information.hpp> - -#include <atomic> -#include <bit> -#include <cstddef> -#include <cstdint> -#include <memory> -#include <optional> -#include <span> -#include <utility> - -namespace teachos::memory -{ - - namespace - { - constexpr auto static unused_page_address = linear_address{0x0000'7fff'cafe'faceuz}; - constexpr auto static recursive_page_map_index = x86_64::page_table::entry_count - 2; - - //! Instantiate a basic, memory region based, early frame allocator for remapping. - auto collect_memory_information() - { - auto memory_map = boot::bootstrap_information.mbi->maybe_memory_map(); - if (!memory_map) - { - system::panic("[x86_64] Failed to create early allocator, no memory map available."); - } - - auto const & mbi = boot::bootstrap_information.mbi; - auto mbi_span = std::span{std::bit_cast<std::byte *>(mbi), mbi->size_bytes()}; - auto image_span = std::span{&boot::x86_64::_start_physical, &boot::x86_64::_end_physical}; - - return x86_64::region_allocator::memory_information{ - .image_range = std::make_pair(physical_address{&image_span.front()}, physical_address{&image_span.back()}), - .mbi_range = std::make_pair(physical_address{&mbi_span.front()}, physical_address{&mbi_span.back()}), - .memory_map = *memory_map, - }; - } - - //! Enable additional CPU protection features, required during later stages of the kernel. - auto enable_cpu_protections() -> void - { - cpu::x86_64::cr0::set(cpu::x86_64::cr0::flags::write_protect); - cpu::x86_64::i32_efer::set(cpu::x86_64::i32_efer::flags::execute_disable_bit_enable); - } - - //! Inject, or graft, a faux recursive PML4 into the active page mapping structure. - auto inject_faux_pml4(frame_allocator & allocator, page_mapper & mapper) - { - using namespace x86_64; - using entry_flags = page_table::entry::flags; - - auto page = page::containing(unused_page_address); - - auto temporary_mapper = scoped_mapping{page, mapper}; - auto new_pml4_frame = allocator.allocate(); - - auto pml4 = std::construct_at(temporary_mapper.map_as<page_table>(*new_pml4_frame, entry_flags::writable)); - (*pml4)[recursive_page_map_index].frame(new_pml4_frame.value(), entry_flags::present | entry_flags::writable); - - auto pml4_index = pml_index<4>(page); - auto old_pml4 = paging_root::get(); - auto pml4_entry = (*old_pml4)[pml4_index]; - - auto pml3_index = pml_index<3>(page); - auto old_pml3 = old_pml4->next(pml4_index); - auto pml3_entry = (**old_pml3)[pml3_index]; - - auto pml2_index = pml_index<2>(page); - auto old_pml2 = (**old_pml3).next(pml3_index); - auto pml2_entry = (**old_pml2)[pml2_index]; - - auto pml1_index = pml_index<1>(page); - auto old_pml1 = (**old_pml2).next(pml2_index); - auto pml1_entry = (**old_pml1)[pml1_index]; - - (*paging_root::get())[recursive_page_map_index].frame(new_pml4_frame.value(), - entry_flags::present | entry_flags::writable); - - tlb_flush_all(); - - auto new_pml4 = paging_root::get(); - (*new_pml4)[pml4_index] = pml4_entry; - - auto new_pml3 = new_pml4->next(pml4_index); - (**new_pml3)[pml3_index] = pml3_entry; - - auto new_pml2 = (**new_pml3).next(pml3_index); - (**new_pml2)[pml2_index] = pml2_entry; - - auto new_pml1 = (**new_pml2).next(pml2_index); - (**new_pml1)[pml1_index] = pml1_entry; - - return *new_pml4_frame; - } - - auto remap_kernel(page_mapper & mapper) -> void - { - auto kernel_mapper = x86_64::kernel_mapper{boot::bootstrap_information.mbi}; - kernel_mapper.remap_kernel(mapper); - } - - auto remap_vga_text_mode_buffer(page_mapper & mapper) -> void - { - constexpr auto vga_base = std::uintptr_t{0xb8000}; - auto vga_physical_start = physical_address{vga_base}; - auto vga_virtual_start = linear_address{vga_base + std::bit_cast<std::uintptr_t>(&boot::x86_64::TEACHOS_VMA)}; - - auto page = page::containing(vga_virtual_start); - auto frame = frame::containing(vga_physical_start); - - mapper.map(page, frame, page_mapper::flags::writable); - } - - auto remap_multiboot_information(page_mapper & mapper) -> void - { - auto mbi_base = std::bit_cast<std::uintptr_t>(boot::bootstrap_information.mbi); - auto mbi_size = boot::bootstrap_information.mbi->size_bytes(); - auto mbi_physical_start = physical_address{mbi_base & ~std::bit_cast<std::uintptr_t>(&boot::x86_64::TEACHOS_VMA)}; - auto mbi_virtual_start = linear_address{mbi_base}; - auto mbi_block_count = (mbi_size + PLATFORM_FRAME_SIZE - 1) / PLATFORM_FRAME_SIZE; - - for (auto i = 0uz; i < mbi_block_count; ++i) - { - auto page = page::containing(mbi_virtual_start) + i; - auto frame = frame::containing(mbi_physical_start) + i; - mapper.map(page, frame, page_mapper::flags::empty); - } - } - - auto constinit region_based_allocator = std::optional<x86_64::region_allocator>{}; - auto constinit buffered_allocator = std::optional<x86_64::buffered_allocator<4>>{}; - auto constinit recursive_page_mapper = std::optional<x86_64::recursive_page_mapper>{}; - - } // namespace - - auto init() -> void - { - auto static constinit is_initialized = std::atomic_flag{}; - - if (is_initialized.test_and_set()) - { - system::panic("[x86_64] Memory management has already been initialized."); - } - - kstd::println("[x86_64:MEM] Enabling additional CPU protection features."); - - enable_cpu_protections(); - - region_based_allocator.emplace(collect_memory_information()); - buffered_allocator.emplace(&*region_based_allocator); - recursive_page_mapper.emplace(*buffered_allocator); - - kstd::println("[x86_64:MEM] Preparing new paging hierarchy."); - - auto new_pml4_frame = inject_faux_pml4(*buffered_allocator, *recursive_page_mapper); - - remap_kernel(*recursive_page_mapper); - remap_vga_text_mode_buffer(*recursive_page_mapper); - remap_multiboot_information(*recursive_page_mapper); - - kstd::println("[x86_64:MEM] Switching to new paging hierarchy."); - - auto cr3 = cpu::x86_64::cr3::read(); - cr3.frame(new_pml4_frame); - cpu::x86_64::cr3::write(cr3); - - set_frame_allocator(*buffered_allocator); - set_page_mapper(*recursive_page_mapper); - } - -} // namespace teachos::memory |
