diff options
| -rw-r--r-- | arch/x86_64/support/grub.cfg.in | 1 | ||||
| -rw-r--r-- | arch/x86_64/support/modules/fat32.img | 3 | ||||
| -rw-r--r-- | kernel/CMakeLists.txt | 1 | ||||
| -rw-r--r-- | kernel/kernel/filesystems/fat32/boot_sector.hpp | 54 | ||||
| -rw-r--r-- | kernel/kernel/filesystems/fat32/driver_state.hpp | 23 | ||||
| -rw-r--r-- | kernel/kernel/filesystems/fat32/error.cpp | 58 | ||||
| -rw-r--r-- | kernel/kernel/filesystems/fat32/error.hpp | 33 | ||||
| -rw-r--r-- | kernel/kernel/filesystems/fat32/filesystem.cpp | 70 | ||||
| -rw-r--r-- | kernel/kernel/filesystems/fat32/filesystem.hpp | 8 | ||||
| -rw-r--r-- | kernel/kernel/filesystems/fat32/filesystem.tests.cpp | 51 | ||||
| -rw-r--r-- | kernel/kernel/main.cpp | 17 | ||||
| l--------- | kernel/kernel/test_support/vfs/test_assets/fat32.img | 1 | ||||
| -rwxr-xr-x | scripts/qemu-wrapper.sh | 2 |
13 files changed, 318 insertions, 4 deletions
diff --git a/arch/x86_64/support/grub.cfg.in b/arch/x86_64/support/grub.cfg.in index 06701fdc..135dc107 100644 --- a/arch/x86_64/support/grub.cfg.in +++ b/arch/x86_64/support/grub.cfg.in @@ -6,5 +6,6 @@ menuentry "TeachOS" { module2 /modules/ext2_4KB_fs.img type=ramdisk module2 /modules/ext2_1KB_fs.img type=ramdisk module2 /modules/ext2_2KB_fs.img type=ramdisk + module2 /modules/fat32.img type=ramdisk boot }
\ No newline at end of file diff --git a/arch/x86_64/support/modules/fat32.img b/arch/x86_64/support/modules/fat32.img new file mode 100644 index 00000000..ff9c6e08 --- /dev/null +++ b/arch/x86_64/support/modules/fat32.img @@ -0,0 +1,3 @@ +version https://git-lfs.github.com/spec/v1 +oid sha256:1eea0fe2e0d9f93ac6a55a25c071329c038f111d085148d5f6a6d1d35e539672 +size 35651584 diff --git a/kernel/CMakeLists.txt b/kernel/CMakeLists.txt index e7464658..aacb5d97 100644 --- a/kernel/CMakeLists.txt +++ b/kernel/CMakeLists.txt @@ -86,6 +86,7 @@ target_sources("kernel_lib" PRIVATE "kernel/filesystems/ext2/write_batch.cpp" # fat32 Filesystem + "kernel/filesystems/fat32/error.cpp" "kernel/filesystems/fat32/filesystem.cpp" "kernel/filesystems/fat32/inode.cpp" "kernel/filesystems/fat32/module.cpp" diff --git a/kernel/kernel/filesystems/fat32/boot_sector.hpp b/kernel/kernel/filesystems/fat32/boot_sector.hpp new file mode 100644 index 00000000..b5789b92 --- /dev/null +++ b/kernel/kernel/filesystems/fat32/boot_sector.hpp @@ -0,0 +1,54 @@ +#ifndef TEACHOS_KERNEL_FILESYSTEMS_FAT32_BOOT_SECTOR_HPP +#define TEACHOS_KERNEL_FILESYSTEMS_FAT32_BOOT_SECTOR_HPP + +#include <array> +#include <cstdint> + +namespace kernel::filesystems::fat32 +{ + //! The boot sector in the fat32 filesystem. + //! + //! The layout follows the "Microsoft Extensible Firmware Initiative FAT32 File System Specification" (fatgen103). + //! The sector consists of the BIOS Parameter Block (BPB) common to all FAT variants, followed by the FAT32 specific + //! extension. + // cspell:ignore fatgen + struct [[gnu::packed]] boot_sector + { + // Common BIOS Parameter Block + std::array<std::uint8_t, 3> jump_boot; + std::array<char, 8> oem_name; + std::uint16_t bytes_per_sector; + std::uint8_t sectors_per_cluster; + std::uint16_t reserved_sector_count; + std::uint8_t number_of_fats; + std::uint16_t root_entry_count; + std::uint16_t total_sectors_16; + std::uint8_t media; + std::uint16_t fat_size_16; + std::uint16_t sectors_per_track; + std::uint16_t number_of_heads; + std::uint32_t hidden_sectors; + std::uint32_t total_sectors_32; + + // FAT32 Extended BIOS Parameter Block + std::uint32_t fat_size_32; + std::uint16_t extended_flags; + std::uint16_t filesystem_version; + std::uint32_t root_cluster; + std::uint16_t filesystem_info_sector; + std::uint16_t backup_boot_sector; + std::array<std::uint8_t, 12> reserved; // NOLINT(readability-magic-numbers) + std::uint8_t drive_number; + std::uint8_t reserved1; + std::uint8_t extended_boot_signature; + std::uint32_t volume_id; + std::array<char, 11> volume_label; // NOLINT(readability-magic-numbers) + std::array<char, 8> filesystem_type; + std::array<std::uint8_t, 420> boot_code; // NOLINT(readability-magic-numbers) + std::uint16_t boot_signature; + }; + + static_assert(sizeof(boot_sector) == 512, "The fat32 boot sector must be exactly 512 bytes in size."); +} // namespace kernel::filesystems::fat32 + +#endif diff --git a/kernel/kernel/filesystems/fat32/driver_state.hpp b/kernel/kernel/filesystems/fat32/driver_state.hpp new file mode 100644 index 00000000..55b90724 --- /dev/null +++ b/kernel/kernel/filesystems/fat32/driver_state.hpp @@ -0,0 +1,23 @@ +#ifndef TEACHOS_KERNEL_FILESYSTEMS_FAT32_DRIVER_STATE_HPP +#define TEACHOS_KERNEL_FILESYSTEMS_FAT32_DRIVER_STATE_HPP + +#include <kernel/filesystems/fat32/boot_sector.hpp> +#include <kernel/vfs/driver_state.hpp> +#include <kernel/vfs/inode.hpp> + +#include <kapi/tracked_mutex.hpp> + +#include <kstd/memory.hpp> +#include <kstd/vector.hpp> + +namespace kernel::filesystems::fat32 +{ + + struct driver_state : vfs::driver_state + { + struct boot_sector boot_sector{}; + }; + +} // namespace kernel::filesystems::fat32 + +#endif
\ No newline at end of file diff --git a/kernel/kernel/filesystems/fat32/error.cpp b/kernel/kernel/filesystems/fat32/error.cpp new file mode 100644 index 00000000..4a18eb9e --- /dev/null +++ b/kernel/kernel/filesystems/fat32/error.cpp @@ -0,0 +1,58 @@ +#include <kernel/filesystems/fat32/error.hpp> + +#include <kernel/vfs/error.hpp> + +#include <kstd/system_error.hpp> + +#include <string_view> + +namespace kernel::filesystems::fat32 +{ + + namespace + { + struct category_t final : kstd::error_category + { + [[nodiscard]] constexpr auto name() const noexcept -> std::string_view override + { + return "fat32"; + } + + [[nodiscard]] constexpr auto message(int value) const noexcept -> std::string_view override + { + switch (static_cast<errc>(value)) + { + case errc::invalid_boot_signature: + return "invalid boot signature"; + default: + return "unknown fat32 error"; + }; + } + + [[nodiscard]] constexpr auto equivalent(int code, kstd::error_condition const & condition) const noexcept + -> bool override + { + switch (static_cast<errc>(code)) + { + case errc::invalid_boot_signature: + if (condition.category() == kernel::vfs::category()) + { + return condition.value() == static_cast<int>(kernel::vfs::errc::invalid_filesystem); + } + else if (condition.category() == kstd::generic_category()) + { + return condition.value() == static_cast<int>(kstd::errc::invalid_argument); + } + break; + } + return kstd::error_category::equivalent(code, condition); + } + } constexpr inline fat32_category_instance{}; + } // namespace + + [[nodiscard]] auto category() noexcept -> kstd::error_category const & + { + return fat32_category_instance; + } + +} // namespace kernel::filesystems::fat32 diff --git a/kernel/kernel/filesystems/fat32/error.hpp b/kernel/kernel/filesystems/fat32/error.hpp new file mode 100644 index 00000000..6955be3f --- /dev/null +++ b/kernel/kernel/filesystems/fat32/error.hpp @@ -0,0 +1,33 @@ +#ifndef TEACHOS_KERNEL_FILESYSTEMS_FAT32_ERROR_HPP +#define TEACHOS_KERNEL_FILESYSTEMS_FAT32_ERROR_HPP + +#include <kernel/vfs/error.hpp> + +#include <kstd/system_error.hpp> + +#include <type_traits> + +namespace kernel::filesystems::fat32 +{ + enum struct errc : int + { + invalid_boot_signature = 1 + }; + + [[nodiscard]] auto category() noexcept -> kstd::error_category const &; + + [[nodiscard]] constexpr auto inline make_error_code(errc error) noexcept -> kstd::error_code + { + return {static_cast<int>(error), category()}; + } +} // namespace kernel::filesystems::fat32 + +namespace kstd +{ + template<> + struct is_error_code_enum<kernel::filesystems::fat32::errc> : std::true_type + { + }; +} // namespace kstd + +#endif
\ No newline at end of file diff --git a/kernel/kernel/filesystems/fat32/filesystem.cpp b/kernel/kernel/filesystems/fat32/filesystem.cpp index a66a9b25..30f1b286 100644 --- a/kernel/kernel/filesystems/fat32/filesystem.cpp +++ b/kernel/kernel/filesystems/fat32/filesystem.cpp @@ -1,5 +1,7 @@ #include <kernel/filesystems/fat32/filesystem.hpp> +#include <kernel/filesystems/fat32/boot_sector.hpp> +#include <kernel/filesystems/fat32/error.hpp> #include <kernel/filesystems/fat32/inode.hpp> #include <kernel/vfs/error.hpp> #include <kernel/vfs/filesystem.hpp> @@ -7,9 +9,14 @@ #include <kapi/filesystem.hpp> #include <kstd/memory.hpp> +#include <kstd/print.hpp> #include <kstd/result.hpp> +#include <kstd/span.hpp> #include <kstd/system_error.hpp> +#include <kstd/units.hpp> +#include <array> +#include <cstddef> #include <cstdint> #include <optional> #include <string_view> @@ -18,13 +25,72 @@ namespace kernel::filesystems::fat32 { static_assert(sizeof(kernel::vfs::filesystem) == sizeof(fat32::filesystem)); + //! Hidden implementation details. + namespace + { + //! Convert a fixed size, space padded character array of the boot sector into a string view. + //! + //! @param array The array to convert. + //! @return A view of the array contents. + template<std::size_t Size> + [[nodiscard]] constexpr auto to_string_view(std::array<char, Size> const & array) -> std::string_view + { + return {array.data(), array.size()}; + } + + //! Print all fields of a boot sector. + //! + //! @param boot_sector The boot sector to print. + auto print_boot_sector(boot_sector const & boot_sector) -> void + { + kstd::println("[OS:FAT32] jump_boot: {:#04X} {:#04X} {:#04X}", boot_sector.jump_boot[0], boot_sector.jump_boot[1], + boot_sector.jump_boot[2]); + kstd::println("[OS:FAT32] oem_name: '{}'", to_string_view(boot_sector.oem_name)); + kstd::println("[OS:FAT32] bytes_per_sector: {}", boot_sector.bytes_per_sector); + kstd::println("[OS:FAT32] sectors_per_cluster: {}", boot_sector.sectors_per_cluster); + kstd::println("[OS:FAT32] reserved_sector_count: {}", boot_sector.reserved_sector_count); + kstd::println("[OS:FAT32] number_of_fats: {}", boot_sector.number_of_fats); + kstd::println("[OS:FAT32] root_entry_count: {}", boot_sector.root_entry_count); + kstd::println("[OS:FAT32] total_sectors_16: {}", boot_sector.total_sectors_16); + kstd::println("[OS:FAT32] media: {:#04X}", boot_sector.media); + kstd::println("[OS:FAT32] fat_size_16: {}", boot_sector.fat_size_16); + kstd::println("[OS:FAT32] sectors_per_track: {}", boot_sector.sectors_per_track); + kstd::println("[OS:FAT32] number_of_heads: {}", boot_sector.number_of_heads); + kstd::println("[OS:FAT32] hidden_sectors: {}", boot_sector.hidden_sectors); + kstd::println("[OS:FAT32] total_sectors_32: {}", boot_sector.total_sectors_32); + kstd::println("[OS:FAT32] fat_size_32: {}", boot_sector.fat_size_32); + kstd::println("[OS:FAT32] extended_flags: {:#06X}", boot_sector.extended_flags); + kstd::println("[OS:FAT32] filesystem_version: {:#06X}", boot_sector.filesystem_version); + kstd::println("[OS:FAT32] root_cluster: {}", boot_sector.root_cluster); + kstd::println("[OS:FAT32] filesystem_info_sector: {}", boot_sector.filesystem_info_sector); + kstd::println("[OS:FAT32] backup_boot_sector: {}", boot_sector.backup_boot_sector); + kstd::println("[OS:FAT32] drive_number: {:#04X}", boot_sector.drive_number); + kstd::println("[OS:FAT32] extended_boot_signature: {:#04X}", boot_sector.extended_boot_signature); + kstd::println("[OS:FAT32] volume_id: {:#010X}", boot_sector.volume_id); + kstd::println("[OS:FAT32] volume_label: '{}'", to_string_view(boot_sector.volume_label)); + kstd::println("[OS:FAT32] filesystem_type: '{}'", to_string_view(boot_sector.filesystem_type)); + kstd::println("[OS:FAT32] boot_signature: {:#06X}", boot_sector.boot_signature); + } + } // namespace + auto filesystem::probe(inode_ptr const & inode) const -> kstd::result<std::uint32_t> { - if (inode) + auto boot_sector = fat32::boot_sector{}; + auto const bytes = kstd::raw_bytes(boot_sector); + auto const read_result = inode->read(bytes, constants::boot_sector_offset); + + if (!read_result) + { + return kstd::failure(read_result.error()); + } + + if (boot_sector.boot_signature != constants::boot_signature) { - return kstd::failure(vfs::errc::invalid_argument); + return kstd::failure(errc::invalid_boot_signature); } + print_boot_sector(boot_sector); + return 0; } diff --git a/kernel/kernel/filesystems/fat32/filesystem.hpp b/kernel/kernel/filesystems/fat32/filesystem.hpp index 8b0b4941..54c8035c 100644 --- a/kernel/kernel/filesystems/fat32/filesystem.hpp +++ b/kernel/kernel/filesystems/fat32/filesystem.hpp @@ -10,6 +10,7 @@ #include <kstd/result.hpp> #include <kstd/string.hpp> #include <kstd/system_error.hpp> +#include <kstd/units.hpp> #include <kstd/vector.hpp> #include <cstdint> @@ -18,6 +19,13 @@ namespace kernel::filesystems::fat32 { + //! Constants related to the fat32 filesystem. + namespace constants + { + constexpr kstd::bytes inline boot_sector_offset = kstd::bytes{0}; + constexpr std::uint16_t inline boot_signature = 0xAA55; + } // namespace constants + //! The File Allocation Table 32 Filesystem (fat32) struct filesystem : kernel::vfs::filesystem { diff --git a/kernel/kernel/filesystems/fat32/filesystem.tests.cpp b/kernel/kernel/filesystems/fat32/filesystem.tests.cpp index cc35cd74..8e4bc8c1 100644 --- a/kernel/kernel/filesystems/fat32/filesystem.tests.cpp +++ b/kernel/kernel/filesystems/fat32/filesystem.tests.cpp @@ -1,15 +1,25 @@ #include <kernel/filesystems/fat32/filesystem.hpp> +#include <kernel/devices/storage.hpp> +#include <kernel/filesystems/fat32/error.hpp> +#include <kernel/test_support/devices/block_device.hpp> +#include <kernel/test_support/vfs/storage_boot_module_fixture.hpp> +#include <kernel/vfs/device_inode.hpp> #include <kernel/vfs/filesystem.hpp> #include <kapi/filesystem.hpp> #include <kstd/memory.hpp> #include <kstd/print.hpp> +#include <kstd/units.hpp> #include <kstd/vector.hpp> #include <catch2/catch_test_macros.hpp> +#include <filesystem> + +using namespace kstd::units_literals; + SCENARIO("fat32 filesystem mount and lookup", "[filesystem][fat32][filesystem]") { GIVEN("a mounted fat32 filesystem") @@ -46,3 +56,44 @@ SCENARIO("fat32 filesystem mount and lookup", "[filesystem][fat32][filesystem]") } } } + +SCENARIO_METHOD(kernel::tests::vfs::storage_boot_module_fixture, "Fat32 filesystem probe with real image", + "[filesystem][fat32][filesystem][img]") +{ + auto const image_path = std::filesystem::path{KERNEL_TEST_ASSETS_DIR} / "fat32.img"; + + GIVEN("a block device containing a fat32 image") + { + REQUIRE(std::filesystem::exists(image_path)); + REQUIRE_NOTHROW(setup_modules_from_img({"test_img_module"}, {image_path})); + + auto boot_device = kernel::devices::storage::determine_boot_device(); + REQUIRE(boot_device); + + auto dev_inode = kstd::make_shared<kernel::vfs::device_inode>(boot_device); + auto fs = kstd::make_shared<kernel::filesystems::fat32::filesystem>(); + + THEN("probe accepts the boot sector") + { + REQUIRE(fs->probe(dev_inode)); + } + } +} + +SCENARIO("Fat32 filesystem rejects invalid boot signature", "[filesystem][fat32][filesystem]") +{ + auto const block_size = 512_B; + GIVEN("a block device that does not contain a fat32 boot sector") + { + auto device = kstd::make_shared<kernel::tests::devices::block_device>("mock", block_size, 2 * block_size); + REQUIRE(device); + + auto dev_inode = kstd::make_shared<kernel::vfs::device_inode>(device); + auto fs = kstd::make_shared<kernel::filesystems::fat32::filesystem>(); + + THEN("probe fails with invalid_boot_signature") + { + REQUIRE(fs->probe(dev_inode).error() == kernel::filesystems::fat32::errc::invalid_boot_signature); + } + } +} diff --git a/kernel/kernel/main.cpp b/kernel/kernel/main.cpp index bc192950..15952547 100644 --- a/kernel/kernel/main.cpp +++ b/kernel/kernel/main.cpp @@ -25,6 +25,21 @@ using namespace kstd::units_literals; +auto run_demo_fat32() -> void +{ + kstd::println("[OS:DEM] Running FAT32 Demo"); + + kstd::println("[OS:DEM] mount /dev/ram3 to /entrance"); + if (auto result = kapi::filesystem::mount("/dev/ram3", "/entrance")) + { + kstd::println("[OS:DEM] mounted /dev/ram3 to /entrance"); + } + else + { + kapi::system::panic("[OS:DEM] failed to mount /dev/ram3 on /entrance", result.error()); + } +} + auto run_demo() -> void { // 1) open a file @@ -312,7 +327,7 @@ auto main() -> int kstd::println("[OS] Virtual filesystem initialized."); // TODO BA-FS26 remove demo code? - run_demo(); + run_demo_fat32(); kapi::system::panic("[OS] Returning from kernel main!"); } diff --git a/kernel/kernel/test_support/vfs/test_assets/fat32.img b/kernel/kernel/test_support/vfs/test_assets/fat32.img new file mode 120000 index 00000000..31031c9f --- /dev/null +++ b/kernel/kernel/test_support/vfs/test_assets/fat32.img @@ -0,0 +1 @@ +../../../../../arch/x86_64/support/modules/fat32.img
\ No newline at end of file diff --git a/scripts/qemu-wrapper.sh b/scripts/qemu-wrapper.sh index dd0200df..5e83f055 100755 --- a/scripts/qemu-wrapper.sh +++ b/scripts/qemu-wrapper.sh @@ -12,7 +12,7 @@ if [ -z "$ISO_PATH" ]; then fi ARGS=( - "-m" "64M" + "-m" "128M" "-machine" "q35" "-smp" "4,sockets=1,cores=4,threads=1" "-display" "curses" |