diff options
Diffstat (limited to 'kernel/src/filesystem/ext2')
| -rw-r--r-- | kernel/src/filesystem/ext2/filesystem.cpp | 247 | ||||
| -rw-r--r-- | kernel/src/filesystem/ext2/filesystem.tests.cpp | 139 | ||||
| -rw-r--r-- | kernel/src/filesystem/ext2/inode.cpp | 111 | ||||
| -rw-r--r-- | kernel/src/filesystem/ext2/inode.tests.cpp | 376 |
4 files changed, 873 insertions, 0 deletions
diff --git a/kernel/src/filesystem/ext2/filesystem.cpp b/kernel/src/filesystem/ext2/filesystem.cpp new file mode 100644 index 0000000..3180a19 --- /dev/null +++ b/kernel/src/filesystem/ext2/filesystem.cpp @@ -0,0 +1,247 @@ +#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 diff --git a/kernel/src/filesystem/ext2/filesystem.tests.cpp b/kernel/src/filesystem/ext2/filesystem.tests.cpp new file mode 100644 index 0000000..8341070 --- /dev/null +++ b/kernel/src/filesystem/ext2/filesystem.tests.cpp @@ -0,0 +1,139 @@ +#include <kernel/filesystem/ext2/filesystem.hpp> + +#include <kernel/devices/storage/management.hpp> +#include <kernel/filesystem/device_inode.hpp> +#include <kernel/filesystem/ext2/inode.hpp> +#include <kernel/filesystem/filesystem.hpp> +#include <kernel/test_support/devices/block_device.hpp> +#include <kernel/test_support/filesystem/ext2.hpp> +#include <kernel/test_support/filesystem/storage_boot_module_fixture.hpp> + +#include <kstd/memory> +#include <kstd/vector> + +#include <catch2/catch_test_macros.hpp> + +#include <array> +#include <cstdint> +#include <filesystem> + +SCENARIO_METHOD(kernel::tests::filesystem::storage_boot_module_fixture, + "Ext2 filesystem mount and lookup with real image", "[filesystem][ext2][filesystem][img]") +{ + auto const image_path = std::filesystem::path{KERNEL_TEST_ASSETS_DIR} / "ext2_1KB_fs.img"; + + GIVEN("a mounted ext2 filesystem from a real image") + { + REQUIRE(std::filesystem::exists(image_path)); + REQUIRE_NOTHROW(setup_modules_from_img({"test_img_module"}, {image_path})); + + auto boot_device = kernel::devices::storage::management::get().determine_boot_device(); + REQUIRE(boot_device != nullptr); + + auto dev_inode = kstd::make_shared<kernel::filesystem::device_inode>(boot_device); + + auto fs = kernel::filesystem::ext2::filesystem{}; + REQUIRE(fs.mount(dev_inode) == kernel::filesystem::filesystem::operation_result::success); + + THEN("the root inode is available and is a directory") + { + REQUIRE(fs.root_inode() != nullptr); + REQUIRE(fs.root_inode()->is_directory()); + } + + THEN("lookup resolves known entries from the image") + { + auto information = fs.lookup(fs.root_inode(), "information"); + REQUIRE(information != nullptr); + REQUIRE(information->is_directory()); + + auto info_1 = fs.lookup(information, "info_1.txt"); + REQUIRE(info_1 != nullptr); + REQUIRE(info_1->is_regular()); + } + + THEN("lookup returns null for invalid inputs") + { + REQUIRE(fs.lookup(nullptr, "information") == nullptr); + + auto information = fs.lookup(fs.root_inode(), "information"); + REQUIRE(information != nullptr); + auto info_1 = fs.lookup(information, "info_1.txt"); + REQUIRE(info_1 != nullptr); + + REQUIRE(fs.lookup(info_1, "anything") == nullptr); + REQUIRE(fs.lookup(fs.root_inode(), "does_not_exist") == nullptr); + } + } +} + +SCENARIO("Ext2 filesystem rejects invalid magic", "[filesystem][ext2][filesystem]") +{ + auto const block_size = 1024; + GIVEN("a block device that does not contain an ext2 superblock") + { + auto device = kstd::make_shared<kernel::tests::devices::block_device>(0, 0, "mock", block_size, 2 * block_size); + REQUIRE(device != nullptr); + + auto dev_inode = kstd::make_shared<kernel::filesystem::device_inode>(device); + + auto fs = kernel::filesystem::ext2::filesystem{}; + + THEN("mount fails with invalid_magic_number") + { + REQUIRE(fs.mount(dev_inode) == kernel::filesystem::filesystem::operation_result::invalid_magic_number); + } + } +} + +SCENARIO("Ext2 block mapping includes direct and all indirect levels", "[filesystem][ext2][filesystem]") +{ + auto const block_size = 1024; + + GIVEN("a minimally valid ext2 layout with configured indirect block tables") + { + auto device = kstd::make_shared<kernel::tests::devices::block_device>(0, 0, "mock", block_size, 128 * block_size); + REQUIRE(device != nullptr); + + kernel::tests::filesystem::ext2::setup_mock_ext2_layout(*device); + + auto dev_inode = kstd::make_shared<kernel::filesystem::device_inode>(device); + + auto fs = kernel::filesystem::ext2::filesystem{}; + REQUIRE(fs.mount(dev_inode) == kernel::filesystem::filesystem::operation_result::success); + + auto inode_data = kernel::filesystem::ext2::inode_data{}; + inode_data.block[0] = 7; + + inode_data.block[12] = 30; + kernel::tests::filesystem::ext2::write_u32(*device, 30 * block_size, 31); + + inode_data.block[13] = 40; + kernel::tests::filesystem::ext2::write_u32(*device, 40 * block_size, 41); + kernel::tests::filesystem::ext2::write_u32(*device, 41 * block_size, 42); + + inode_data.block[14] = 50; + kernel::tests::filesystem::ext2::write_u32(*device, 50 * block_size, 51); + kernel::tests::filesystem::ext2::write_u32(*device, 51 * block_size, 52); + kernel::tests::filesystem::ext2::write_u32(*device, 52 * block_size, 53); + + auto const numbers_per_block = static_cast<uint32_t>(block_size / sizeof(uint32_t)); + auto const singly_start = static_cast<uint32_t>(kernel::filesystem::ext2::constants::direct_block_count); + auto const doubly_start = singly_start + numbers_per_block; + auto const triply_start = doubly_start + numbers_per_block * numbers_per_block; + + THEN("mapping resolves direct, singly, doubly and triply indirect indexes") + { + REQUIRE(fs.map_inode_block_index_to_global_block_number(0, inode_data) == 7); + REQUIRE(fs.map_inode_block_index_to_global_block_number(singly_start, inode_data) == 31); + REQUIRE(fs.map_inode_block_index_to_global_block_number(doubly_start, inode_data) == 42); + REQUIRE(fs.map_inode_block_index_to_global_block_number(triply_start, inode_data) == 53); + } + + THEN("mapping returns zero for out-of-range indexes") + { + auto const beyond_triply = triply_start + numbers_per_block * numbers_per_block * numbers_per_block; + REQUIRE(fs.map_inode_block_index_to_global_block_number(beyond_triply, inode_data) == -1); + } + } +} diff --git a/kernel/src/filesystem/ext2/inode.cpp b/kernel/src/filesystem/ext2/inode.cpp new file mode 100644 index 0000000..35a32ee --- /dev/null +++ b/kernel/src/filesystem/ext2/inode.cpp @@ -0,0 +1,111 @@ +#include <kernel/filesystem/ext2/inode.hpp> + +#include <kernel/filesystem/ext2/filesystem.hpp> +#include <kernel/filesystem/inode.hpp> + +#include <kapi/system.hpp> + +#include <kstd/cstring> + +#include <algorithm> +#include <cstddef> +#include <cstdint> + +namespace kernel::filesystem::ext2 +{ + inode::inode(filesystem const * fs, inode_data const & data) + : m_filesystem(fs) + , m_data(data) + { + if (!m_filesystem) + { + kapi::system::panic("[EXT2] ext2::inode constructed with filesystem null pointer"); + } + } + + auto inode::read(void * buffer, size_t offset, size_t size) const -> size_t + { + auto const max_readable = this->size() - offset; + auto const requested_size = std::min(size, max_readable); + + if (is_symbolic_link() && this->size() <= sizeof(m_data.block)) + { + auto inline_target = reinterpret_cast<uint8_t const *>(m_data.block.data()); + kstd::libc::memcpy(static_cast<uint8_t *>(buffer), inline_target + offset, requested_size); + return requested_size; + } + + auto block_index = offset / m_filesystem->block_size(); + auto in_block_offset = offset % m_filesystem->block_size(); + + auto bytes_read = 0uz; + + while (bytes_read < requested_size) + { + auto const block_number = m_filesystem->map_inode_block_index_to_global_block_number(block_index, m_data); + if (block_number == -1) + { + break; + } + + auto const bytes_to_read = std::min(requested_size - bytes_read, m_filesystem->block_size() - in_block_offset); + if (block_number == 0) + { + kstd::libc::memset(static_cast<uint8_t *>(buffer) + bytes_read, 0, bytes_to_read); + bytes_read += bytes_to_read; + } + else + { + auto const block_start_offset = block_number * m_filesystem->block_size(); + auto const read_offset = block_start_offset + in_block_offset; + + bytes_read += m_filesystem->backing_inode()->read(static_cast<uint8_t *>(buffer) + bytes_read, read_offset, + bytes_to_read); + } + + block_index++; + in_block_offset = 0; // After the first block, we always start at the beginning of the block + } + + return bytes_read; + } + + auto inode::write(void const *, size_t, size_t) -> size_t + { + kapi::system::panic("[EXT2] inode::write is not implemented yet"); + return 0; + } + + [[nodiscard]] auto inode::data() const -> inode_data const & + { + return m_data; + } + + auto inode::is_regular() const -> bool + { + return (m_data.mode & constants::mode_mask) == constants::mode_regular; + } + + auto inode::is_directory() const -> bool + { + return (m_data.mode & constants::mode_mask) == constants::mode_directory; + } + + auto inode::is_symbolic_link() const -> bool + { + return (m_data.mode & constants::mode_mask) == constants::mode_symbolic_link; + } + + auto inode::size() const -> uint64_t + { + uint64_t size = m_data.size; + + if (m_filesystem->revision_level() > constants::good_old_revision && is_regular()) + { + size |= static_cast<uint64_t>(m_data.dir_acl) << 32; + } + + return size; + } + +} // namespace kernel::filesystem::ext2 diff --git a/kernel/src/filesystem/ext2/inode.tests.cpp b/kernel/src/filesystem/ext2/inode.tests.cpp new file mode 100644 index 0000000..4aecc04 --- /dev/null +++ b/kernel/src/filesystem/ext2/inode.tests.cpp @@ -0,0 +1,376 @@ +#include <kernel/filesystem/ext2/inode.hpp> + +#include <kernel/devices/storage/management.hpp> +#include <kernel/filesystem/device_inode.hpp> +#include <kernel/filesystem/ext2/filesystem.hpp> +#include <kernel/filesystem/ext2/superblock.hpp> +#include <kernel/filesystem/filesystem.hpp> +#include <kernel/test_support/cpu.hpp> +#include <kernel/test_support/devices/block_device.hpp> +#include <kernel/test_support/filesystem/ext2.hpp> +#include <kernel/test_support/filesystem/storage_boot_module_fixture.hpp> + +#include <kstd/memory> +#include <kstd/vector> + +#include <catch2/catch_test_macros.hpp> + +#include <algorithm> +#include <cstddef> +#include <filesystem> +#include <string_view> + +SCENARIO("Ext2 inode initialization and properties", "[filesystem][ext2][inode]") +{ + GIVEN("an ext2 filesystem") + { + auto fs = kernel::filesystem::ext2::filesystem{}; + auto data = kernel::filesystem::ext2::inode_data{}; + + THEN("the inode is initialized with regular file mode in data and has the kind regular") + { + data.mode = kernel::filesystem::ext2::constants::mode_regular; + auto inode = kernel::filesystem::ext2::inode(&fs, data); + + REQUIRE(inode.is_regular()); + REQUIRE_FALSE(inode.is_directory()); + REQUIRE_FALSE(inode.is_device()); + REQUIRE_FALSE(inode.is_symbolic_link()); + } + + THEN("the inode is initialized with directory mode in data and has the kind directory") + { + data.mode = kernel::filesystem::ext2::constants::mode_directory; + auto inode = kernel::filesystem::ext2::inode(&fs, data); + + REQUIRE_FALSE(inode.is_regular()); + REQUIRE(inode.is_directory()); + REQUIRE_FALSE(inode.is_device()); + REQUIRE_FALSE(inode.is_symbolic_link()); + } + + THEN("the inode is initialized with symbolic link mode in data and has the kind symbolic link") + { + data.mode = kernel::filesystem::ext2::constants::mode_symbolic_link; + auto inode = kernel::filesystem::ext2::inode(&fs, data); + + REQUIRE_FALSE(inode.is_regular()); + REQUIRE_FALSE(inode.is_directory()); + REQUIRE_FALSE(inode.is_device()); + REQUIRE(inode.is_symbolic_link()); + } + + THEN("the inode is initialized with zero mode in data and has no specific kind") + { + data.mode = 0; + auto inode = kernel::filesystem::ext2::inode(&fs, data); + + REQUIRE_FALSE(inode.is_regular()); + REQUIRE_FALSE(inode.is_directory()); + REQUIRE_FALSE(inode.is_device()); + REQUIRE_FALSE(inode.is_symbolic_link()); + } + } + + GIVEN("no filesystem (null pointer)") + { + THEN("constructing an inode with a null filesystem pointer panics") + { + REQUIRE_THROWS_AS(kernel::filesystem::ext2::inode(nullptr, {}), kernel::tests::cpu::halt); + } + } +} + +SCENARIO_METHOD(kernel::tests::filesystem::storage_boot_module_fixture, "Ext2 inode reads from real image", + "[filesystem][ext2][inode][img]") +{ + auto const image_path = std::filesystem::path{KERNEL_TEST_ASSETS_DIR} / "ext2_1KB_fs.img"; + + GIVEN("a mounted ext2 filesystem and a regular file inode") + { + REQUIRE(std::filesystem::exists(image_path)); + REQUIRE_NOTHROW(setup_modules_from_img({"test_img_module"}, {image_path})); + + auto boot_device = kernel::devices::storage::management::get().determine_boot_device(); + REQUIRE(boot_device != nullptr); + + auto dev_inode = kstd::make_shared<kernel::filesystem::device_inode>(boot_device); + + auto fs = kernel::filesystem::ext2::filesystem{}; + REQUIRE(fs.mount(dev_inode) == kernel::filesystem::filesystem::operation_result::success); + + auto information = fs.lookup(fs.root_inode(), "information"); + REQUIRE(information != nullptr); + auto file = fs.lookup(information, "info_1.txt"); + REQUIRE(file != nullptr); + REQUIRE(file->is_regular()); + + THEN("reading from offset zero returns expected file prefix") + { + auto buffer = kstd::vector<std::byte>(6); + auto const bytes_read = file->read(buffer.data(), 0, buffer.size()); + + REQUIRE(bytes_read == 6); + + auto const text = std::string_view{reinterpret_cast<char const *>(buffer.data()), bytes_read}; + REQUIRE(text == "info_1"); + } + + THEN("reading with an offset returns the expected byte") + { + auto buffer = kstd::vector<std::byte>(1); + auto const bytes_read = file->read(buffer.data(), 5, buffer.size()); + + REQUIRE(bytes_read == 1); + REQUIRE(static_cast<char>(buffer[0]) == '1'); + } + } +} + +SCENARIO("Ext2 inode handles zeros in block mappings as file holes", "[filesystem][ext2][inode]") +{ + auto const block_size = 1024uz; + GIVEN("an ext2 inode with only direct mapped data blocks") + { + auto device = kstd::make_shared<kernel::tests::devices::block_device>(0, 0, "mock", block_size, 64 * block_size); + REQUIRE(device != nullptr); + kernel::tests::filesystem::ext2::setup_mock_ext2_layout(*device); + + auto dev_inode = kstd::make_shared<kernel::filesystem::device_inode>(device); + + auto fs = kernel::filesystem::ext2::filesystem{}; + REQUIRE(fs.mount(dev_inode) == kernel::filesystem::filesystem::operation_result::success); + + auto data = kernel::filesystem::ext2::inode_data{}; + data.block[0] = 30; + data.block[1] = 0; + data.block[2] = 31; + data.size = block_size * 3; + + kernel::tests::filesystem::ext2::write_bytes(*device, 30 * block_size, "Hello", 5); + kernel::tests::filesystem::ext2::write_bytes(*device, 31 * block_size, "World!", 6); + + auto inode = kernel::filesystem::ext2::inode{&fs, data}; + + auto buffer = kstd::vector<std::byte>(data.size, std::byte{0xAB}); + + THEN("correct number of bytes are read and holes are returned as zeros") + { + auto const bytes_read = inode.read(buffer.data(), 0, buffer.size()); + REQUIRE(bytes_read == data.size); + + auto const text = std::string_view{reinterpret_cast<char const *>(buffer.data()), bytes_read}; + REQUIRE(text.substr(0, 5) == "Hello"); + REQUIRE(std::ranges::all_of(text.substr(5, block_size - 5), [](char c) { return c == '\0'; })); + REQUIRE(text.substr(2 * block_size, 6) == "World!"); + REQUIRE(std::ranges::all_of(text.substr(2 * block_size + 6, 3 * block_size), [](char c) { return c == '\0'; })); + } + } + + GIVEN("an ext2 indode with file holes in singly indirect blocks") + { + auto device = kstd::make_shared<kernel::tests::devices::block_device>(0, 0, "mock", block_size, 64 * block_size); + REQUIRE(device != nullptr); + kernel::tests::filesystem::ext2::setup_mock_ext2_layout(*device); + + auto dev_inode = kstd::make_shared<kernel::filesystem::device_inode>(device); + + auto fs = kernel::filesystem::ext2::filesystem{}; + REQUIRE(fs.mount(dev_inode) == kernel::filesystem::filesystem::operation_result::success); + + auto data = kernel::filesystem::ext2::inode_data{}; + data.block[0] = 30; + data.block[12] = 31; + data.size = block_size * 15; + + kernel::tests::filesystem::ext2::write_u32(*device, 31 * block_size, 50); + kernel::tests::filesystem::ext2::write_u32(*device, 31 * block_size + 4, 0); + kernel::tests::filesystem::ext2::write_u32(*device, 31 * block_size + 8, 51); + + kernel::tests::filesystem::ext2::write_bytes(*device, 30 * block_size, "Hello", 5); + kernel::tests::filesystem::ext2::write_bytes(*device, 50 * block_size, "Blub", 4); + kernel::tests::filesystem::ext2::write_bytes(*device, 51 * block_size, "World!", 6); + + auto inode = kernel::filesystem::ext2::inode{&fs, data}; + + auto buffer = kstd::vector<std::byte>(data.size, std::byte{0xAB}); + + THEN("correct number of bytes are read and holes are returned as zeros") + { + auto const bytes_read = inode.read(buffer.data(), 0, buffer.size()); + REQUIRE(bytes_read == data.size); + + auto const text = std::string_view{reinterpret_cast<char const *>(buffer.data()), bytes_read}; + REQUIRE(text.substr(0, 5) == "Hello"); + REQUIRE(std::ranges::all_of(text.substr(5, 12 * block_size - 5), [](char c) { return c == '\0'; })); + REQUIRE(text.substr(12 * block_size, 4) == "Blub"); + REQUIRE( + std::ranges::all_of(text.substr(12 * block_size + 4, 2 * block_size - 4), [](char c) { return c == '\0'; })); + REQUIRE(text.substr(14 * block_size, 6) == "World!"); + REQUIRE( + std::ranges::all_of(text.substr(14 * block_size + 6, 1 * block_size - 6), [](char c) { return c == '\0'; })); + } + } + + GIVEN("an ext2 inode with zero singly indirect block pointer") + { + auto device = kstd::make_shared<kernel::tests::devices::block_device>(0, 0, "mock", block_size, 64 * block_size); + REQUIRE(device != nullptr); + kernel::tests::filesystem::ext2::setup_mock_ext2_layout(*device); + + auto dev_inode = kstd::make_shared<kernel::filesystem::device_inode>(device); + + auto fs = kernel::filesystem::ext2::filesystem{}; + REQUIRE(fs.mount(dev_inode) == kernel::filesystem::filesystem::operation_result::success); + + auto data = kernel::filesystem::ext2::inode_data{}; + data.block[12] = 0; + data.size = block_size * 15; + + auto inode = kernel::filesystem::ext2::inode{&fs, data}; + + auto buffer = kstd::vector<std::byte>(block_size * 15, std::byte{0xAB}); + + THEN("all direct blocks are zero when singly indirect block pointer is zero") + { + auto const bytes_read = inode.read(buffer.data(), 0, buffer.size()); + REQUIRE(bytes_read == buffer.size()); + REQUIRE(std::ranges::all_of(buffer, [](std::byte c) { return c == std::byte{0x00}; })); + } + } +} + +SCENARIO("Ext2 inode read across block boundaries", "[filesystem][ext2][inode]") +{ + auto const block_size = 1024uz; + GIVEN("an ext2 inode with two direct blocks and a block size of 1024 bytes") + { + auto device = kstd::make_shared<kernel::tests::devices::block_device>(0, 0, "mock", block_size, 64 * block_size); + REQUIRE(device != nullptr); + kernel::tests::filesystem::ext2::setup_mock_ext2_layout(*device); + + auto dev_inode = kstd::make_shared<kernel::filesystem::device_inode>(device); + + auto fs = kernel::filesystem::ext2::filesystem{}; + REQUIRE(fs.mount(dev_inode) == kernel::filesystem::filesystem::operation_result::success); + + auto inode_data = kernel::filesystem::ext2::inode_data{}; + inode_data.size = block_size * 2; + inode_data.block[0] = 20; + kernel::tests::filesystem::ext2::write_bytes(*device, 21 * block_size - 6, "Hello ", 6); + inode_data.block[1] = 21; + kernel::tests::filesystem::ext2::write_bytes(*device, 21 * block_size, "World!", 6); + auto inode = kernel::filesystem::ext2::inode{&fs, inode_data}; + + auto buffer = kstd::vector<std::byte>(12, std::byte{0x00}); + + THEN("reading across the block boundary returns the combined content") + { + auto const bytes_read = inode.read(buffer.data(), block_size - 6, buffer.size()); + REQUIRE(bytes_read == 12); + + auto const text = std::string_view{reinterpret_cast<char const *>(buffer.data()), bytes_read}; + REQUIRE(text == "Hello World!"); + } + } +} + +SCENARIO("Ext2 inode write is not implemented", "[filesystem][ext2][inode]") +{ + GIVEN("an ext2 inode") + { + auto fs = kernel::filesystem::ext2::filesystem{}; + auto inode = kernel::filesystem::ext2::inode{&fs, kernel::filesystem::ext2::inode_data{}}; + + THEN("writing to the inode panics") + { + auto buffer = kstd::vector<std::byte>(32, std::byte{0x00}); + REQUIRE_THROWS_AS(inode.write(buffer.data(), 0, buffer.size()), kernel::tests::cpu::halt); + } + } +} + +SCENARIO("Ext2 inode get_size() correctly returns size depending on revision level", "[filesystem][ext2][inode]") +{ + auto const block_size = 1024uz; + + auto superblock = kernel::filesystem::ext2::superblock{}; + superblock.magic = kernel::filesystem::ext2::constants::magic_number; + superblock.log_block_size = 0; + superblock.blocks_count = 64; + superblock.blocks_per_group = 64; + superblock.inodes_per_group = 32; + superblock.inode_size = 128; + + GIVEN("an ext2 inode with good old revision and inode_data.size = 256, inode_data.dir_acl = 32") + { + superblock.rev_level = 0; + + auto device = kstd::make_shared<kernel::tests::devices::block_device>(0, 0, "mock", block_size, 64 * block_size); + REQUIRE(device != nullptr); + kernel::tests::filesystem::ext2::setup_mock_ext2_layout(*device, superblock); + + auto dev_inode = kstd::make_shared<kernel::filesystem::device_inode>(device); + + auto fs = kernel::filesystem::ext2::filesystem{}; + REQUIRE(fs.mount(dev_inode) == kernel::filesystem::filesystem::operation_result::success); + + auto data = kernel::filesystem::ext2::inode_data{}; + data.size = 256; + data.dir_acl = 32; + + THEN("the inode size is 256 if mode = regular") + { + data.mode = kernel::filesystem::ext2::constants::mode_regular; + + auto inode = kernel::filesystem::ext2::inode{&fs, data}; + + REQUIRE(inode.size() == 256); + } + + THEN("the inode size is 256 if mode = directory") + { + data.mode = kernel::filesystem::ext2::constants::mode_directory; + + auto inode = kernel::filesystem::ext2::inode{&fs, data}; + + REQUIRE(inode.size() == 256); + } + } + + GIVEN("an ext2 inode with good dynamic revision and inode_data.size = 256, inode_data.dir_acl = 32") + { + superblock.rev_level = 1; + + auto device = kstd::make_shared<kernel::tests::devices::block_device>(0, 0, "mock", block_size, 64 * block_size); + REQUIRE(device != nullptr); + kernel::tests::filesystem::ext2::setup_mock_ext2_layout(*device, superblock); + + auto dev_inode = kstd::make_shared<kernel::filesystem::device_inode>(device); + + auto fs = kernel::filesystem::ext2::filesystem{}; + REQUIRE(fs.mount(dev_inode) == kernel::filesystem::filesystem::operation_result::success); + + auto data = kernel::filesystem::ext2::inode_data{}; + data.size = 256; + data.dir_acl = 32; + + THEN("the inode size is 256 if mode = regular") + { + data.mode = kernel::filesystem::ext2::constants::mode_regular; + + auto inode = kernel::filesystem::ext2::inode{&fs, data}; + + REQUIRE(inode.size() == 0x0000'0020'0000'0100); + } + + THEN("the inode size is 256 if mode = directory") + { + data.mode = kernel::filesystem::ext2::constants::mode_directory; + + auto inode = kernel::filesystem::ext2::inode{&fs, data}; + + REQUIRE(inode.size() == 256); + } + } +}
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