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authorFelix Morgner <felix.morgner@ost.ch>2026-07-03 09:32:30 +0200
committerFelix Morgner <felix.morgner@ost.ch>2026-07-03 09:32:30 +0200
commit3012fa5dfe5dfed5e83baf9b40934ed8e8317627 (patch)
tree00d1c60a3d5d1cdfa55e0ff1691cd3362b6064ee /kernel/src/filesystem/ext2/filesystem.cpp
parent5d8a58d538515ffc57ddf82ba40ba763990a8696 (diff)
downloadkernel-3012fa5dfe5dfed5e83baf9b40934ed8e8317627.tar.xz
kernel-3012fa5dfe5dfed5e83baf9b40934ed8e8317627.zip
kernel: rearrange sources according to p1204
Diffstat (limited to 'kernel/src/filesystem/ext2/filesystem.cpp')
-rw-r--r--kernel/src/filesystem/ext2/filesystem.cpp247
1 files changed, 0 insertions, 247 deletions
diff --git a/kernel/src/filesystem/ext2/filesystem.cpp b/kernel/src/filesystem/ext2/filesystem.cpp
deleted file mode 100644
index 3180a19a..00000000
--- a/kernel/src/filesystem/ext2/filesystem.cpp
+++ /dev/null
@@ -1,247 +0,0 @@
-#include <kernel/filesystem/ext2/filesystem.hpp>
-
-#include <kernel/filesystem/ext2/block_group_descriptor.hpp>
-#include <kernel/filesystem/ext2/inode.hpp>
-#include <kernel/filesystem/ext2/linked_directory_entry.hpp>
-#include <kernel/filesystem/ext2/superblock.hpp>
-#include <kernel/filesystem/filesystem.hpp>
-#include <kernel/filesystem/inode.hpp>
-#include <kernel/filesystem/type.hpp>
-
-#include <kstd/memory>
-#include <kstd/unikstd.h>
-#include <kstd/vector>
-
-#include <array>
-#include <cstddef>
-#include <cstdint>
-#include <string_view>
-
-namespace kernel::filesystem::ext2
-{
-
- struct type final : kernel::filesystem::type
- {
- [[nodiscard]] auto name() const noexcept -> std::string_view override
- {
- return "ext2";
- }
-
- [[nodiscard]] auto requires_device() const noexcept -> bool override
- {
- return true;
- }
-
- [[nodiscard]] auto make_instance() const -> kstd::shared_ptr<kernel::filesystem::filesystem> override
- {
- return kstd::make_shared<filesystem>();
- }
- };
-
- [[gnu::used]]
- constexpr auto registration = type_registration<type>{};
-
- auto filesystem::mount(kstd::shared_ptr<kernel::filesystem::inode> const & backing_inode) -> operation_result
- {
- kernel::filesystem::filesystem::mount(backing_inode);
-
- m_backing_inode->read(&m_superblock, constants::superblock_offset, sizeof(m_superblock));
-
- if (m_superblock.magic != constants::magic_number)
- {
- return operation_result::invalid_magic_number;
- }
-
- auto const blocks_per_group = m_superblock.blocks_per_group;
- auto const num_block_groups = (m_superblock.blocks_count + blocks_per_group - 1) / blocks_per_group;
-
- m_block_group_descriptors = kstd::vector<block_group_descriptor>(num_block_groups);
-
- m_backing_inode->read(m_block_group_descriptors.data(), block_group_descriptor_table_offset(),
- num_block_groups * sizeof(block_group_descriptor));
-
- m_root_inode = read_inode(constants::root_inode_number);
-
- if (!m_root_inode || !m_root_inode->is_directory())
- {
- return operation_result::invalid_root_inode;
- }
- return operation_result::success;
- }
-
- auto filesystem::lookup(kstd::shared_ptr<kernel::filesystem::inode> const & parent, std::string_view name) const
- -> kstd::shared_ptr<kernel::filesystem::inode>
- {
- if (!parent || !parent->is_directory())
- {
- return nullptr;
- }
-
- auto * ext2_parent = static_cast<inode *>(parent.get());
- if (!ext2_parent)
- {
- return nullptr;
- }
-
- auto const & inode_data = ext2_parent->data();
- kstd::vector<uint8_t> buffer(block_size());
-
- for (uint32_t i = 0; i < inode_block_count(inode_data); ++i)
- {
- auto const global_block_number = map_inode_block_index_to_global_block_number(i, inode_data);
- auto const block_offset = global_block_number * block_size();
- m_backing_inode->read(buffer.data(), block_offset, block_size());
-
- auto const * entry = reinterpret_cast<linked_directory_entry const *>(buffer.data());
- auto bytes_read = 0uz;
-
- while (bytes_read < block_size() && entry->inode != 0)
- {
- auto const entry_name = std::string_view{entry->name.data(), entry->name_len};
- if (entry_name == name)
- {
- return read_inode(entry->inode);
- }
-
- bytes_read += entry->rec_len;
- entry = reinterpret_cast<linked_directory_entry const *>(buffer.data() + bytes_read);
- }
- }
-
- return nullptr;
- }
-
- auto filesystem::read_inode(uint32_t inode_number) const -> kstd::shared_ptr<inode>
- {
- auto const inodes_per_group = m_superblock.inodes_per_group;
- auto const block_group_index = (inode_number - 1) / inodes_per_group;
- auto const inode_index_within_group = (inode_number - 1) % inodes_per_group;
-
- if (block_group_index >= m_block_group_descriptors.size())
- {
- return nullptr;
- }
-
- auto const & block_group_descriptor = m_block_group_descriptors.at(block_group_index);
- auto const inode_table_start_block = block_group_descriptor.inode_table;
- auto const inode_table_offset = static_cast<size_t>(inode_table_start_block) * block_size();
- auto const inode_offset = inode_table_offset + inode_index_within_group * inode_size();
-
- auto new_inode_data = inode_data{};
- m_backing_inode->read(&new_inode_data, inode_offset, sizeof(inode_data));
-
- return kstd::make_shared<inode>(this, new_inode_data);
- }
-
- auto filesystem::indirect_levels() const -> std::array<indirect_level, 3>
- {
- return {
- {{constants::singly_indirect_block_index, block_numbers_per_singly_indirect_block()},
- {constants::doubly_indirect_block_index, block_numbers_per_doubly_indirect_block()},
- {constants::triply_indirect_block_index, block_numbers_per_triply_indirect_block()}}
- };
- }
-
- auto filesystem::map_inode_block_index_to_global_block_number(size_t inode_block_index, inode_data data) const
- -> kstd::ssize_t
- {
- if (inode_block_index < constants::direct_block_count)
- {
- return data.block.at(inode_block_index);
- }
-
- inode_block_index -= constants::direct_block_count;
-
- for (auto const & level : indirect_levels())
- {
- if (inode_block_index >= level.capacity)
- {
- inode_block_index -= level.capacity;
- continue;
- }
-
- auto block_number = data.block[level.slot_index];
- if (block_number == 0)
- {
- return 0;
- }
-
- for (auto stride = level.capacity / block_numbers_per_block();; stride /= block_numbers_per_block())
- {
- auto const idx = inode_block_index / stride;
- inode_block_index %= stride;
-
- block_number = read_block_number_at_index(block_number, idx);
- if (block_number == 0)
- {
- return 0;
- }
-
- if (stride == 1)
- {
- break;
- }
- }
-
- return block_number;
- }
-
- return -1;
- }
-
- auto filesystem::read_block_number_at_index(uint32_t block_number, size_t index) const -> uint32_t
- {
- uint32_t block_number_buffer = 0;
-
- auto const block_start_offset = block_number * block_size();
- auto const number_start_address = block_start_offset + index * sizeof(uint32_t);
- m_backing_inode->read(&block_number_buffer, number_start_address, sizeof(uint32_t));
-
- return block_number_buffer;
- }
-
- auto filesystem::block_numbers_per_block() const -> size_t
- {
- return block_size() / sizeof(uint32_t);
- }
-
- auto filesystem::block_numbers_per_singly_indirect_block() const -> size_t
- {
- return block_numbers_per_block();
- }
-
- auto filesystem::block_numbers_per_doubly_indirect_block() const -> size_t
- {
- return block_numbers_per_singly_indirect_block() * block_numbers_per_block();
- }
-
- auto filesystem::block_numbers_per_triply_indirect_block() const -> size_t
- {
- return block_numbers_per_doubly_indirect_block() * block_numbers_per_block();
- }
-
- auto filesystem::block_size() const -> size_t
- {
- return constants::base_block_size << m_superblock.log_block_size;
- }
-
- auto filesystem::revision_level() const -> uint32_t
- {
- return m_superblock.rev_level;
- }
-
- auto filesystem::inode_size() const -> uint16_t
- {
- return revision_level() == constants::good_old_revision ? 128 : m_superblock.inode_size;
- }
-
- auto filesystem::inode_block_count(inode_data const & data) const -> uint32_t
- {
- return data.blocks / (2 << m_superblock.log_block_size);
- }
-
- auto filesystem::block_group_descriptor_table_offset() const -> size_t
- {
- return block_size() == 1024 ? 2 * block_size() : block_size();
- }
-} // namespace kernel::filesystem::ext2