rm: add option to remove recursively

fsck now reports clean filesystem even after deleting files

BAN/include/BAN/ByteSpan.h

@@ -87,9 +87,12 @@ namespace BAN
 			return *reinterpret_cast<S*>(m_data);
 		}
 
-		ByteSpanGeneral slice(size_type offset, size_type length)
+		ByteSpanGeneral slice(size_type offset, size_type length = size_type(-1))
 		{
 			ASSERT(m_data);
+			ASSERT(m_size >= offset);
+			if (length == size_type(-1))
+				length = m_size - offset;
 			ASSERT(m_size >= offset + length);
 			return ByteSpanGeneral(m_data + offset, length);
 		}

CMakeLists.txt

@@ -23,7 +23,7 @@ add_subdirectory(LibELF)
 add_subdirectory(userspace)
 
 add_custom_target(sysroot
-	COMMAND mkdir -p ${BANAN_SYSROOT}
+	COMMAND ${CMAKE_COMMAND} -E make_directory ${BANAN_SYSROOT}
 	COMMAND cd ${BANAN_SYSROOT} && sudo tar xf ${BANAN_BASE_SYSROOT}
 	USES_TERMINAL
 )

kernel/include/kernel/FS/Ext2/FileSystem.h

@@ -58,7 +58,7 @@ namespace Kernel
 		BAN::ErrorOr<void> initialize_root_inode();
 
 		BAN::ErrorOr<uint32_t> create_inode(const Ext2::Inode&);
-		BAN::ErrorOr<void> delete_inode(uint32_t);
+		void delete_inode(uint32_t ino);
 		BAN::ErrorOr<void> resize_inode(uint32_t, size_t);
 
 		void read_block(uint32_t, BlockBufferWrapper&);
@@ -68,8 +68,9 @@ namespace Kernel
 		BlockBufferWrapper get_block_buffer();
 
 		BAN::ErrorOr<uint32_t> reserve_free_block(uint32_t primary_bgd);
+		void release_block(uint32_t block);
 
-		BAN::HashMap<ino_t, BAN::RefPtr<Inode>>& inode_cache() { return m_inode_cache; }
+		BAN::HashMap<ino_t, BAN::RefPtr<Ext2Inode>>& inode_cache() { return m_inode_cache; }
 
 		const Ext2::Superblock& superblock() const { return m_superblock; }
 
@@ -110,7 +111,7 @@ namespace Kernel
 		BAN::RefPtr<Inode> m_root_inode;
 		BAN::Vector<uint32_t> m_superblock_backups;
 
-		BAN::HashMap<ino_t, BAN::RefPtr<Inode>> m_inode_cache;
+		BAN::HashMap<ino_t, BAN::RefPtr<Ext2Inode>> m_inode_cache;
 
 		BlockBufferManager m_buffer_manager;
 

kernel/include/kernel/FS/Ext2/Inode.h

@@ -13,6 +13,8 @@ namespace Kernel
 	class Ext2Inode final : public Inode
 	{
 	public:
+		~Ext2Inode();
+
 		virtual ino_t ino() const override { return m_ino; };
 		virtual Mode mode() const override { return { m_inode.mode }; }
 		virtual nlink_t nlink() const override { return m_inode.links_count; }
@@ -31,6 +33,8 @@ namespace Kernel
 		virtual BAN::ErrorOr<BAN::RefPtr<Inode>> find_inode_impl(BAN::StringView) override;
 		virtual BAN::ErrorOr<void> list_next_inodes_impl(off_t, DirectoryEntryList*, size_t) override;
 		virtual BAN::ErrorOr<void> create_file_impl(BAN::StringView, mode_t, uid_t, gid_t) override;
+		virtual BAN::ErrorOr<void> create_directory_impl(BAN::StringView, mode_t, uid_t, gid_t) override;
+		virtual BAN::ErrorOr<void> unlink_impl(BAN::StringView) override;
 		
 		virtual BAN::ErrorOr<BAN::String> link_target_impl() override;
 
@@ -42,8 +46,14 @@ namespace Kernel
 	private:
 		uint32_t fs_block_of_data_block_index(uint32_t data_block_index);
 
+		BAN::ErrorOr<void> link_inode_to_directory(Ext2Inode&, BAN::StringView name);
+		BAN::ErrorOr<bool> is_directory_empty();
+
+		BAN::ErrorOr<void> cleanup_default_links();
+		void cleanup_from_fs();
+
 		BAN::ErrorOr<uint32_t> allocate_new_block();
-		BAN::ErrorOr<void> sync();
+		void sync();
 
 		uint32_t block_group() const;
 
@@ -53,7 +63,7 @@ namespace Kernel
 			, m_inode(inode)
 			, m_ino(ino)
 		{}
-		static BAN::ErrorOr<BAN::RefPtr<Inode>> create(Ext2FS&, uint32_t);
+		static BAN::ErrorOr<BAN::RefPtr<Ext2Inode>> create(Ext2FS&, uint32_t);
 
 	private:
 		Ext2FS& m_fs;

kernel/include/kernel/FS/Inode.h

@@ -90,7 +90,8 @@ namespace Kernel
 		BAN::ErrorOr<BAN::RefPtr<Inode>> find_inode(BAN::StringView);
 		BAN::ErrorOr<void> list_next_inodes(off_t, DirectoryEntryList*, size_t);
 		BAN::ErrorOr<void> create_file(BAN::StringView, mode_t, uid_t, gid_t);
-		BAN::ErrorOr<void> delete_inode(BAN::StringView);
+		BAN::ErrorOr<void> create_directory(BAN::StringView, mode_t, uid_t, gid_t);
+		BAN::ErrorOr<void> unlink(BAN::StringView);
 
 		// Link API
 		BAN::ErrorOr<BAN::String> link_target();
@@ -107,7 +108,8 @@ namespace Kernel
 		virtual BAN::ErrorOr<BAN::RefPtr<Inode>> find_inode_impl(BAN::StringView)				{ return BAN::Error::from_errno(ENOTSUP); }
 		virtual BAN::ErrorOr<void> list_next_inodes_impl(off_t, DirectoryEntryList*, size_t)	{ return BAN::Error::from_errno(ENOTSUP); }
 		virtual BAN::ErrorOr<void> create_file_impl(BAN::StringView, mode_t, uid_t, gid_t)		{ return BAN::Error::from_errno(ENOTSUP); }
-		virtual BAN::ErrorOr<void> delete_inode_impl(BAN::StringView)							{ return BAN::Error::from_errno(ENOTSUP); }
+		virtual BAN::ErrorOr<void> create_directory_impl(BAN::StringView, mode_t, uid_t, gid_t)	{ return BAN::Error::from_errno(ENOTSUP); }
+		virtual BAN::ErrorOr<void> unlink_impl(BAN::StringView)									{ return BAN::Error::from_errno(ENOTSUP); }
 
 		// Link API
 		virtual BAN::ErrorOr<BAN::String> link_target_impl()				{ return BAN::Error::from_errno(ENOTSUP); }

kernel/include/kernel/FS/RamFS/Inode.h

@@ -96,7 +96,8 @@ namespace Kernel
 		virtual BAN::ErrorOr<BAN::RefPtr<Inode>> find_inode_impl(BAN::StringView) override;
 		virtual BAN::ErrorOr<void> list_next_inodes_impl(off_t, DirectoryEntryList*, size_t) override;
 		virtual BAN::ErrorOr<void> create_file_impl(BAN::StringView, mode_t, uid_t, gid_t) override;
-		virtual BAN::ErrorOr<void> delete_inode_impl(BAN::StringView) override;
+		virtual BAN::ErrorOr<void> create_directory_impl(BAN::StringView, mode_t, uid_t, gid_t) override;
+		virtual BAN::ErrorOr<void> unlink_impl(BAN::StringView) override;
 
 	private:
 		static constexpr size_t m_name_max = NAME_MAX;

kernel/include/kernel/Process.h

@@ -89,13 +89,16 @@ namespace Kernel
 		BAN::ErrorOr<long> sys_getegid() const { return m_credentials.egid(); }
 		BAN::ErrorOr<long> sys_getpgid(pid_t);
 
-		BAN::ErrorOr<void> create_file(BAN::StringView name, mode_t mode);
+		BAN::ErrorOr<void> create_file_or_dir(BAN::StringView name, mode_t mode);
 		BAN::ErrorOr<long> open_file(BAN::StringView path, int, mode_t = 0);
 		BAN::ErrorOr<long> sys_open(const char* path, int, mode_t);
 		BAN::ErrorOr<long> sys_openat(int, const char* path, int, mode_t);
 		BAN::ErrorOr<long> sys_close(int fd);
 		BAN::ErrorOr<long> sys_read(int fd, void* buffer, size_t count);
 		BAN::ErrorOr<long> sys_write(int fd, const void* buffer, size_t count);
+		BAN::ErrorOr<long> sys_create(const char*, mode_t);
+		BAN::ErrorOr<long> sys_create_dir(const char*, mode_t);
+		BAN::ErrorOr<long> sys_unlink(const char*);
 
 		BAN::ErrorOr<long> sys_chmod(const char*, mode_t);
 

kernel/kernel/FS/Ext2/FileSystem.cpp

@@ -184,6 +184,8 @@ namespace Kernel
 			write_block(bgd->inode_bitmap, inode_bitmap);
 
 			bgd->free_inodes_count--;
+			if (Inode::Mode(ext2_inode.mode).ifdir())
+				bgd->used_dirs_count++;
 			write_block(bgd_location.block, bgd_buffer);
 
 			const uint32_t inode_table_offset = ino_index * superblock().inode_size;
@@ -212,6 +214,55 @@ namespace Kernel
 		return BAN::Error::from_error_code(ErrorCode::Ext2_Corrupted);
 	}
 
+	void Ext2FS::delete_inode(uint32_t ino)
+	{
+		LockGuard _(m_lock);
+
+		ASSERT(ino >= superblock().first_ino);
+		ASSERT(ino <= superblock().inodes_count);
+
+		auto bgd_buffer = get_block_buffer();
+		auto bitmap_buffer = get_block_buffer();
+		auto inode_buffer = get_block_buffer();
+
+		const uint32_t inode_group = (ino - 1) / superblock().inodes_per_group;
+		const uint32_t inode_index = (ino - 1) % superblock().inodes_per_group;
+
+		auto bgd_location = locate_block_group_descriptior(inode_group);
+		read_block(bgd_location.block, bgd_buffer);
+		auto& bgd = bgd_buffer.span().slice(bgd_location.offset).as<Ext2::BlockGroupDescriptor>();
+
+		// update inode bitmap
+		read_block(bgd.inode_bitmap, bitmap_buffer);
+		const uint32_t byte = inode_index / 8;
+		const uint32_t bit  = inode_index % 8;
+		ASSERT(bitmap_buffer[byte] & (1 << bit));
+		bitmap_buffer[byte] &= ~(1 << bit);
+		write_block(bgd.inode_bitmap, bitmap_buffer);
+
+		// memset inode to zero or fsck will complain
+		auto inode_location = locate_inode(ino);
+		read_block(inode_location.block, inode_buffer);
+		auto& inode = inode_buffer.span().slice(inode_location.offset).as<Ext2::Inode>();
+		bool is_directory = Inode::Mode(inode.mode).ifdir();
+		memset(&inode, 0x00, m_superblock.inode_size);
+		write_block(inode_location.block, inode_buffer);
+
+		// update bgd counts
+		bgd.free_inodes_count++;
+		if (is_directory)
+			bgd.used_dirs_count--;
+		write_block(bgd_location.block, bgd_buffer);
+
+		// update superblock inode count
+		m_superblock.free_inodes_count++;
+		sync_superblock();
+
+		// remove inode from cache
+		if (m_inode_cache.contains(ino))
+			m_inode_cache.remove(ino);
+	}
+
 	void Ext2FS::read_block(uint32_t block, BlockBufferWrapper& buffer)
 	{
 		LockGuard _(m_lock);
@@ -255,8 +306,7 @@ namespace Kernel
 		const uint32_t lba = 1024 / sector_size;
 		const uint32_t sector_count = BAN::Math::div_round_up<uint32_t>(superblock_bytes, sector_size);
 
-		BAN::Vector<uint8_t> superblock_buffer;
+		auto superblock_buffer = get_block_buffer();
-		MUST(superblock_buffer.resize(sector_count * sector_size));
 
 		MUST(m_partition.read_sectors(lba, sector_count, superblock_buffer.span()));
 		if (memcmp(superblock_buffer.data(), &m_superblock, superblock_bytes))
@@ -266,7 +316,6 @@ namespace Kernel
 		}
 	}
 
-
 	Ext2FS::BlockBufferWrapper Ext2FS::get_block_buffer()
 	{
 		LockGuard _(m_lock);
@@ -334,6 +383,39 @@ namespace Kernel
 		return BAN::Error::from_error_code(ErrorCode::Ext2_Corrupted);
 	}
 
+	void Ext2FS::release_block(uint32_t block)
+	{
+		LockGuard _(m_lock);
+
+		ASSERT(block >= m_superblock.first_data_block);
+		ASSERT(block < m_superblock.blocks_count);
+
+		const uint32_t block_group = (block - m_superblock.first_data_block) / m_superblock.blocks_per_group;
+		const uint32_t block_offset = (block - m_superblock.first_data_block) % m_superblock.blocks_per_group;
+
+		auto bgd_buffer = get_block_buffer();
+		auto bitmap_buffer = get_block_buffer();
+
+		auto bgd_location = locate_block_group_descriptior(block_group);
+		read_block(bgd_location.block, bgd_buffer);
+
+		auto& bgd = bgd_buffer.span().slice(bgd_location.offset).as<Ext2::BlockGroupDescriptor>();
+		read_block(bgd.block_bitmap, bitmap_buffer);
+
+		const uint32_t byte = block_offset / 8;
+		const uint32_t bit  = block_offset % 8;
+		ASSERT(bitmap_buffer[byte] & (1 << bit));
+
+		bitmap_buffer[byte] &= ~(1 << bit);
+		write_block(bgd.block_bitmap, bitmap_buffer);
+
+		bgd.free_blocks_count++;
+		write_block(bgd_location.block, bgd_buffer);
+
+		m_superblock.free_blocks_count++;
+		sync_superblock();
+	}
+
 	Ext2FS::BlockLocation Ext2FS::locate_inode(uint32_t ino)
 	{
 		LockGuard _(m_lock);

kernel/kernel/FS/Ext2/Inode.cpp

@@ -1,4 +1,5 @@
 #include <BAN/Function.h>
+#include <BAN/ScopeGuard.h>
 #include <kernel/FS/Ext2/FileSystem.h>
 #include <kernel/FS/Ext2/Inode.h>
 #include <kernel/Timer/Timer.h>
@@ -21,7 +22,7 @@ namespace Kernel
 		return (m_ino - 1) / m_fs.superblock().blocks_per_group;
 	}
 
-	BAN::ErrorOr<BAN::RefPtr<Inode>> Ext2Inode::create(Ext2FS& fs, uint32_t inode_ino)
+	BAN::ErrorOr<BAN::RefPtr<Ext2Inode>> Ext2Inode::create(Ext2FS& fs, uint32_t inode_ino)
 	{
 		if (fs.inode_cache().contains(inode_ino))
 			return fs.inode_cache()[inode_ino];
@@ -36,11 +37,17 @@ namespace Kernel
 		Ext2Inode* result_ptr = new Ext2Inode(fs, inode, inode_ino);
 		if (result_ptr == nullptr)
 			return BAN::Error::from_errno(ENOMEM);
-		auto result = BAN::RefPtr<Inode>::adopt(result_ptr);
+		auto result = BAN::RefPtr<Ext2Inode>::adopt(result_ptr);
 		TRY(fs.inode_cache().insert(inode_ino, result));
 		return result;
 	}
 
+	Ext2Inode::~Ext2Inode()
+	{
+		if (m_inode.links_count == 0)
+			cleanup_from_fs();
+	}
+
 #define VERIFY_AND_READ_BLOCK(expr) do { const uint32_t block_index = expr; ASSERT(block_index); m_fs.read_block(block_index, block_buffer); } while (false)
 #define VERIFY_AND_RETURN(expr) ({ const uint32_t result = expr; ASSERT(result); return result; })
 
@@ -214,7 +221,7 @@ namespace Kernel
 		if (new_size < m_inode.size)
 		{
 			m_inode.size = new_size;
-			TRY(sync());
+			sync();
 			return {};
 		}
 
@@ -237,7 +244,7 @@ namespace Kernel
 		}
 
 		m_inode.size = new_size;
-		TRY(sync());
+		sync();
 
 		return {};
 	}
@@ -248,10 +255,18 @@ namespace Kernel
 		if (m_inode.mode == mode)
 			return {};
 		m_inode.mode = (m_inode.mode & Inode::Mode::TYPE_MASK) | mode;
-		TRY(sync());
+		sync();
 		return {};
 	}
 
+	void Ext2Inode::cleanup_from_fs()
+	{
+		ASSERT(m_inode.links_count == 0);
+		for (uint32_t i = 0; i < blocks(); i++)
+			m_fs.release_block(fs_block_of_data_block_index(i));
+		m_fs.delete_inode(ino());
+	}
+
 	BAN::ErrorOr<void> Ext2Inode::list_next_inodes_impl(off_t offset, DirectoryEntryList* list, size_t list_size)
 	{
 		ASSERT(mode().ifdir());
@@ -317,7 +332,100 @@ namespace Kernel
 		return {};
 	}
 
+	static bool mode_has_valid_type(mode_t mode)
+	{
+		switch (mode & Inode::Mode::TYPE_MASK)
+		{
+			case Inode::Mode::IFIFO: return true;
+			case Inode::Mode::IFCHR: return true;
+			case Inode::Mode::IFDIR: return true;
+			case Inode::Mode::IFBLK: return true;
+			case Inode::Mode::IFREG: return true;
+			case Inode::Mode::IFLNK: return true;
+			case Inode::Mode::IFSOCK: return true;
+		}
+		return false;
+	}
+
+	static Ext2::Inode initialize_new_inode_info(mode_t mode, uid_t uid, gid_t gid)
+	{
+		ASSERT(mode_has_valid_type(mode));
+
+		timespec current_time = SystemTimer::get().real_time();
+		return Ext2::Inode
+		{
+			.mode			= (uint16_t)mode,
+			.uid			= (uint16_t)uid,
+			.size			= 0,
+			.atime 			= (uint32_t)current_time.tv_sec,
+			.ctime 			= (uint32_t)current_time.tv_sec,
+			.mtime 			= (uint32_t)current_time.tv_sec,
+			.dtime 			= 0,
+			.gid			= (uint16_t)gid,
+			.links_count	= 0,
+			.blocks			= 0,
+			.flags			= 0,
+			.osd1			= 0,
+			.block 			= {},
+			.generation		= 0,
+			.file_acl		= 0,
+			.dir_acl		= 0,
+			.faddr			= 0,
+			.osd2 			= {}
+		};
+	}
+
 	BAN::ErrorOr<void> Ext2Inode::create_file_impl(BAN::StringView name, mode_t mode, uid_t uid, gid_t gid)
+	{
+		ASSERT(this->mode().ifdir());
+
+		if (!(Mode(mode).ifreg()))
+			return BAN::Error::from_errno(ENOTSUP);
+
+		const uint32_t new_ino = TRY(m_fs.create_inode(initialize_new_inode_info(mode, uid, gid)));
+
+		auto inode_or_error = Ext2Inode::create(m_fs, new_ino);
+		if (inode_or_error.is_error())
+		{
+			m_fs.delete_inode(new_ino);
+			return inode_or_error.release_error();
+		}
+
+		auto inode = inode_or_error.release_value();
+
+		TRY(link_inode_to_directory(*inode, name));
+
+		return {};
+	}
+
+	BAN::ErrorOr<void> Ext2Inode::create_directory_impl(BAN::StringView name, mode_t mode, uid_t uid, gid_t gid)
+	{
+		ASSERT(this->mode().ifdir());
+		ASSERT(Mode(mode).ifdir());
+
+		const uint32_t new_ino = TRY(m_fs.create_inode(initialize_new_inode_info(mode, uid, gid)));
+
+		auto inode_or_error = Ext2Inode::create(m_fs, new_ino);
+		if (inode_or_error.is_error())
+		{
+			m_fs.delete_inode(new_ino);
+			return inode_or_error.release_error();
+		}
+
+		auto inode = inode_or_error.release_value();
+		BAN::ScopeGuard cleanup([&] { inode->cleanup_from_fs(); });
+
+		TRY(inode->link_inode_to_directory(*inode, "."sv));
+		TRY(inode->link_inode_to_directory(*this, ".."sv));
+		
+		TRY(link_inode_to_directory(*inode, name));
+
+		cleanup.disable();
+
+		return {};
+	}
+
+	BAN::ErrorOr<void> Ext2Inode::link_inode_to_directory(Ext2Inode& inode, BAN::StringView name)
 	{
 		if (!this->mode().ifdir())
 			return BAN::Error::from_errno(ENOTDIR);
@@ -325,9 +433,6 @@ namespace Kernel
 		if (name.size() > 255)
 			return BAN::Error::from_errno(ENAMETOOLONG);
 
-		if (!(Mode(mode).ifreg()))
-			return BAN::Error::from_errno(EINVAL);
-
 		if (m_inode.flags & Ext2::Enum::INDEX_FL)
 		{
 			dwarnln("file creation to indexed directory not supported");
@@ -340,39 +445,13 @@ namespace Kernel
 		if (error_or.error().get_error_code() != ENOENT)
 			return error_or.error();
 
-		timespec current_time = SystemTimer::get().real_time();
-
-		Ext2::Inode ext2_inode
-		{
-			.mode			= (uint16_t)mode,
-			.uid			= (uint16_t)uid,
-			.size			= 0,
-			.atime 			= (uint32_t)current_time.tv_sec,
-			.ctime 			= (uint32_t)current_time.tv_sec,
-			.mtime 			= (uint32_t)current_time.tv_sec,
-			.dtime 			= 0,
-			.gid			= (uint16_t)gid,
-			.links_count	= 1,
-			.blocks			= 0,
-			.flags			= 0,
-			.osd1			= 0,
-			.block 			= {},
-			.generation		= 0,
-			.file_acl		= 0,
-			.dir_acl		= 0,
-			.faddr			= 0,
-			.osd2 			= {}
-		};
-
-		const uint32_t inode_index = TRY(m_fs.create_inode(ext2_inode));
-
 		const uint32_t block_size = m_fs.block_size();
 
 		auto block_buffer = m_fs.get_block_buffer();
 
 		auto write_inode = [&](uint32_t entry_offset, uint32_t entry_rec_len)
 		{
-			auto typed_mode = Mode(mode);
+			auto typed_mode = inode.mode();
 			uint8_t file_type = (m_fs.superblock().rev_level == Ext2::Enum::GOOD_OLD_REV) ? 0
 				: typed_mode.ifreg()  ? Ext2::Enum::REG_FILE
 				: typed_mode.ifdir()  ? Ext2::Enum::DIR
@@ -384,11 +463,14 @@ namespace Kernel
 				: 0;
 
 			auto& new_entry = *(Ext2::LinkedDirectoryEntry*)(block_buffer.data() + entry_offset);
-			new_entry.inode = inode_index;
+			new_entry.inode = inode.ino();
 			new_entry.rec_len = entry_rec_len;
 			new_entry.name_len = name.size();
 			new_entry.file_type = file_type;
 			memcpy(new_entry.name, name.data(), name.size());
+
+			inode.m_inode.links_count++;
+			inode.sync();
 		};
 
 		uint32_t block_index = 0;
@@ -443,6 +525,149 @@ needs_new_block:
 		return {};
 	}
 
+	BAN::ErrorOr<bool> Ext2Inode::is_directory_empty()
+	{
+		ASSERT(mode().ifdir());
+		if (m_inode.flags & Ext2::Enum::INDEX_FL)
+		{
+			dwarnln("deletion of indexed directory is not supported");
+			return BAN::Error::from_errno(ENOTSUP);
+		}
+
+		auto block_buffer = m_fs.get_block_buffer();
+
+		// Confirm that this doesn't contain anything else than '.' or '..'
+		for (uint32_t i = 0; i < blocks(); i++)
+		{
+			const uint32_t block = fs_block_of_data_block_index(i);
+			m_fs.read_block(block, block_buffer);
+
+			blksize_t offset = 0;
+			while (offset < blksize())
+			{
+				auto& entry = block_buffer.span().slice(offset).as<Ext2::LinkedDirectoryEntry>();
+
+				if (entry.inode)
+				{
+					BAN::StringView entry_name(entry.name, entry.name_len);
+					if (entry_name != "."sv && entry_name != ".."sv)
+						return false;
+				}
+
+				offset += entry.rec_len;
+			}
+		}
+
+		return true;
+	}
+
+	BAN::ErrorOr<void> Ext2Inode::cleanup_default_links()
+	{
+		ASSERT(mode().ifdir());
+
+		auto block_buffer = m_fs.get_block_buffer();
+
+		for (uint32_t i = 0; i < blocks(); i++)
+		{
+			const uint32_t block = fs_block_of_data_block_index(i);
+			m_fs.read_block(block, block_buffer);
+
+			bool modified = false;
+
+			blksize_t offset = 0;
+			while (offset < blksize())
+			{
+				auto& entry = block_buffer.span().slice(offset).as<Ext2::LinkedDirectoryEntry>();
+
+				if (entry.inode)
+				{
+					BAN::StringView entry_name(entry.name, entry.name_len);
+
+					if (entry_name == "."sv)
+					{
+						m_inode.links_count--;
+						sync();
+					}
+					else if (entry_name == ".."sv)
+					{
+						auto parent = TRY(Ext2Inode::create(m_fs, entry.inode));
+						parent->m_inode.links_count--;
+						parent->sync();
+					}
+					else
+						ASSERT_NOT_REACHED();
+
+					modified = true;
+					entry.inode = 0;
+				}
+
+				offset += entry.rec_len;
+			}
+
+			if (modified)
+				m_fs.write_block(block, block_buffer);
+		}
+
+		return {};
+	}
+
+	BAN::ErrorOr<void> Ext2Inode::unlink_impl(BAN::StringView name)
+	{
+		ASSERT(mode().ifdir());
+		if (m_inode.flags & Ext2::Enum::INDEX_FL)
+		{
+			dwarnln("deletion from indexed directory is not supported");
+			return BAN::Error::from_errno(ENOTSUP);
+		}
+
+		auto block_buffer = m_fs.get_block_buffer();
+
+		for (uint32_t i = 0; i < blocks(); i++)
+		{
+			const uint32_t block = fs_block_of_data_block_index(i);
+			m_fs.read_block(block, block_buffer);
+
+			blksize_t offset = 0;
+			while (offset < blksize())
+			{
+				auto& entry = block_buffer.span().slice(offset).as<Ext2::LinkedDirectoryEntry>();
+				if (entry.inode && name == BAN::StringView(entry.name, entry.name_len))
+				{
+					auto inode = TRY(Ext2Inode::create(m_fs, entry.inode));
+					if (inode->mode().ifdir())
+					{
+						if (!TRY(inode->is_directory_empty()))
+							return BAN::Error::from_errno(ENOTEMPTY);
+						TRY(inode->cleanup_default_links());
+					}
+
+					if (inode->nlink() == 0)
+						dprintln("Corrupted filesystem. Deleting inode with 0 links");
+					else
+						inode->m_inode.links_count--;
+
+					sync();
+
+					// NOTE: If this was the last link to inode we must
+					//       remove it from inode cache to trigger cleanup
+					if (inode->nlink() == 0)
+					{
+						auto& cache = m_fs.inode_cache();
+						if (cache.contains(inode->ino()))
+							cache.remove(inode->ino());
+					}
+
+					// FIXME: This should expand the last inode if exists
+					entry.inode = 0;
+					m_fs.write_block(block, block_buffer);					
+				}
+				offset += entry.rec_len;
+			}
+		}
+
+		return {};
+	}
+
 #define READ_OR_ALLOCATE_BASE_BLOCK(index_)											\
 	do {																			\
 		if (m_inode.block[index_] != 0)												\
@@ -496,7 +721,7 @@ needs_new_block:
 			{
 				if (mode().ifdir())
 					m_inode.size += blksize();
-				MUST(sync());
+				sync();
 			};
 
 		// direct block
@@ -552,7 +777,7 @@ needs_new_block:
 #undef READ_OR_ALLOCATE_INDIRECT_BLOCK
 #undef WRITE_BLOCK_AND_RETURN
 
-	BAN::ErrorOr<void> Ext2Inode::sync()
+	void Ext2Inode::sync()
 	{
 		auto inode_location = m_fs.locate_inode(ino());
 		auto block_buffer = m_fs.get_block_buffer();
@@ -563,8 +788,6 @@ needs_new_block:
 			memcpy(block_buffer.data() + inode_location.offset, &m_inode, sizeof(Ext2::Inode));
 			m_fs.write_block(inode_location.block, block_buffer);
 		}
-
-		return {};
 	}
 
 	BAN::ErrorOr<BAN::RefPtr<Inode>> Ext2Inode::find_inode_impl(BAN::StringView file_name)
@@ -589,7 +812,7 @@ needs_new_block:
 				const auto& entry = *(const Ext2::LinkedDirectoryEntry*)entry_addr;
 				BAN::StringView entry_name(entry.name, entry.name_len);
 				if (entry.inode && entry_name == file_name)
-					return TRY(Ext2Inode::create(m_fs, entry.inode));
+					return BAN::RefPtr<Inode>(TRY(Ext2Inode::create(m_fs, entry.inode)));
 				entry_addr += entry.rec_len;
 			}
 		}

kernel/kernel/FS/Inode.cpp

@@ -81,16 +81,31 @@ namespace Kernel
 		Thread::TerminateBlocker blocker(Thread::current());
 		if (!this->mode().ifdir())
 			return BAN::Error::from_errno(ENOTDIR);
+		if (Mode(mode).ifdir())
+			return BAN::Error::from_errno(EINVAL);
 		return create_file_impl(name, mode, uid, gid);
 	}
 
-	BAN::ErrorOr<void> Inode::delete_inode(BAN::StringView name)
+	BAN::ErrorOr<void> Inode::create_directory(BAN::StringView name, mode_t mode, uid_t uid, gid_t gid)
+	{
+		LockGuard _(m_lock);
+		Thread::TerminateBlocker blocker(Thread::current());
+		if (!this->mode().ifdir())
+			return BAN::Error::from_errno(ENOTDIR);
+		if (!Mode(mode).ifdir())
+			return BAN::Error::from_errno(EINVAL);
+		return create_directory_impl(name, mode, uid, gid);
+	}
+
+	BAN::ErrorOr<void> Inode::unlink(BAN::StringView name)
 	{
 		LockGuard _(m_lock);
 		Thread::TerminateBlocker blocker(Thread::current());
 		if (!mode().ifdir())
 			return BAN::Error::from_errno(ENOTDIR);
-		return delete_inode_impl(name);
+		if (name == "."sv || name == ".."sv)
+			return BAN::Error::from_errno(EINVAL);
+		return unlink_impl(name);
 	}
 
 	BAN::ErrorOr<BAN::String> Inode::link_target()

kernel/kernel/FS/ProcFS/FileSystem.cpp

@@ -40,7 +40,7 @@ namespace Kernel
 	void ProcFileSystem::on_process_delete(Process& process)
 	{
 		auto path = BAN::String::formatted("{}", process.pid());
-		MUST(m_root_inode->delete_inode(path));
+		MUST(m_root_inode->unlink(path));
 	}
 
 }

kernel/kernel/FS/RamFS/Inode.cpp

@@ -202,16 +202,23 @@ namespace Kernel
 		BAN::RefPtr<RamInode> inode;
 		if (Mode(mode).ifreg())
 			inode = TRY(RamFileInode::create(m_fs, mode & ~Inode::Mode::TYPE_MASK, uid, gid));
-		else if (Mode(mode).ifdir())
-			inode = TRY(RamDirectoryInode::create(m_fs, ino(), mode & ~Inode::Mode::TYPE_MASK, uid, gid));
 		else
-			ASSERT_NOT_REACHED();
+			return BAN::Error::from_errno(ENOTSUP);
 
 		TRY(add_inode(name, inode));
 
 		return {};
 	}
 
+	BAN::ErrorOr<void> RamDirectoryInode::create_directory_impl(BAN::StringView name, mode_t mode, uid_t uid, gid_t gid)
+	{
+		if (!Mode(mode).ifdir())
+			return BAN::Error::from_errno(EINVAL);
+		auto inode = TRY(RamDirectoryInode::create(m_fs, ino(), mode & ~Inode::Mode::TYPE_MASK, uid, gid));
+		TRY(add_inode(name, inode));
+		return {};
+	}
+
 	static uint8_t get_type(Inode::Mode mode)
 	{
 		if (mode.ifreg())
@@ -256,8 +263,9 @@ namespace Kernel
 		return {};
 	}
 
-	BAN::ErrorOr<void> RamDirectoryInode::delete_inode_impl(BAN::StringView name)
+	BAN::ErrorOr<void> RamDirectoryInode::unlink_impl(BAN::StringView name)
 	{
+		// FIXME: delete inodes contents only after they are closed
 		for (size_t i = 0; i < m_entries.size(); i++)
 		{
 			if (name == m_entries[i].name)

kernel/kernel/Process.cpp

@@ -611,8 +611,17 @@ namespace Kernel
 		return 0;
 	}
 
-	BAN::ErrorOr<void> Process::create_file(BAN::StringView path, mode_t mode)
+	BAN::ErrorOr<void> Process::create_file_or_dir(BAN::StringView path, mode_t mode)
 	{
+		switch (mode & Inode::Mode::TYPE_MASK)
+		{
+			case Inode::Mode::IFREG: break;
+			case Inode::Mode::IFDIR: break;
+			case Inode::Mode::IFIFO: break;
+			default:
+				return BAN::Error::from_errno(EINVAL);
+		}
+
 		LockGuard _(m_lock);
 
 		auto absolute_path = TRY(absolute_path_of(path));
@@ -625,8 +634,12 @@ namespace Kernel
 		auto directory = absolute_path.sv().substring(0, index);
 		auto file_name = absolute_path.sv().substring(index);
 
-		auto parent_inode = TRY(VirtualFileSystem::get().file_from_absolute_path(m_credentials, directory, O_WRONLY)).inode;
+		auto parent_inode = TRY(VirtualFileSystem::get().file_from_absolute_path(m_credentials, directory, O_EXEC | O_WRONLY)).inode;
-		TRY(parent_inode->create_file(file_name, S_IFREG | (mode & 0777), m_credentials.euid(), m_credentials.egid()));
+
+		if (Inode::Mode(mode).ifdir())
+			TRY(parent_inode->create_directory(file_name, mode, m_credentials.euid(), m_credentials.egid()));
+		else
+			TRY(parent_inode->create_file(file_name, mode, m_credentials.euid(), m_credentials.egid()));
 
 		return {};
 	}
@@ -672,7 +685,7 @@ namespace Kernel
 			if (file_or_error.is_error())
 			{
 				if (file_or_error.error().get_error_code() == ENOENT)
-					TRY(create_file(path, mode));
+					TRY(create_file_or_dir(path, Inode::Mode::IFREG | mode));
 				else
 					return file_or_error.release_error();
 			}
@@ -733,6 +746,42 @@ namespace Kernel
 		return TRY(m_open_file_descriptors.write(fd, BAN::ByteSpan((uint8_t*)buffer, count)));
 	}
 
+	BAN::ErrorOr<long> Process::sys_create(const char* path, mode_t mode)
+	{
+		LockGuard _(m_lock);
+		validate_string_access(path);
+		TRY(create_file_or_dir(path, mode));
+		return 0;
+	}
+
+	BAN::ErrorOr<long> Process::sys_create_dir(const char* path, mode_t mode)
+	{
+		LockGuard _(m_lock);
+		validate_string_access(path);
+		TRY(create_file_or_dir(path, Inode::Mode::IFDIR | mode));
+		return 0;
+	}
+
+	BAN::ErrorOr<long> Process::sys_unlink(const char* path)
+	{
+		LockGuard _(m_lock);
+		validate_string_access(path);
+		
+		auto absolute_path = TRY(absolute_path_of(path));
+
+		size_t index = absolute_path.size();
+		for (; index > 0; index--)
+			if (absolute_path[index - 1] == '/')
+				break;
+		auto directory = absolute_path.sv().substring(0, index);
+		auto file_name = absolute_path.sv().substring(index);
+
+		auto parent = TRY(VirtualFileSystem::get().file_from_absolute_path(m_credentials, directory, O_EXEC | O_WRONLY)).inode;
+		TRY(parent->unlink(file_name));
+
+		return 0;
+	}
+
 	BAN::ErrorOr<long> Process::sys_chmod(const char* path, mode_t mode)
 	{
 		if (mode & S_IFMASK)

kernel/kernel/Syscall.cpp

@@ -202,6 +202,15 @@ namespace Kernel
 		case SYS_CHMOD:
 			ret = Process::current().sys_chmod((const char*)arg1, (mode_t)arg2);
 			break;
+		case SYS_CREATE:
+			ret = Process::current().sys_create((const char*)arg1, (mode_t)arg2);
+			break;
+		case SYS_CREATE_DIR:
+			ret = Process::current().sys_create_dir((const char*)arg1, (mode_t)arg2);
+			break;
+		case SYS_UNLINK:
+			ret = Process::current().sys_unlink((const char*)arg1);
+			break;
 		default:
 			dwarnln("Unknown syscall {}", syscall);
 			break;

libc/fcntl.cpp

@@ -4,6 +4,11 @@
 #include <sys/syscall.h>
 #include <unistd.h>
 
+int creat(const char* path, mode_t mode)
+{
+	return syscall(SYS_CREATE, path, S_IFREG | mode);
+}
+
 int open(const char* path, int oflag, ...)
 {
 	va_list args;

libc/include/sys/syscall.h

@@ -56,6 +56,9 @@ __BEGIN_DECLS
 #define SYS_TTY_CTRL 53
 #define SYS_POWEROFF 54
 #define SYS_CHMOD 55
+#define SYS_CREATE 56 // creat, mkfifo
+#define SYS_CREATE_DIR 57 // mkdir
+#define SYS_UNLINK 58
 
 __END_DECLS
 

libc/sys/stat.cpp

@@ -28,3 +28,8 @@ int stat(const char* __restrict path, struct stat* __restrict buf)
 {
 	return syscall(SYS_STAT, path, buf, 0);
 }
+
+int mkdir(const char* path, mode_t mode)
+{
+	return syscall(SYS_CREATE_DIR, path, mode);
+}

libc/unistd.cpp

@@ -210,6 +210,11 @@ void syncsync(int should_block)
 	syscall(SYS_SYNC, should_block);
 }
 
+int unlink(const char* path)
+{
+	return syscall(SYS_UNLINK, path);
+}
+
 pid_t getpid(void)
 {
 	return syscall(SYS_GET_PID);

userspace/CMakeLists.txt

@@ -13,8 +13,10 @@ set(USERSPACE_PROJECTS
 	init
 	ls
 	meminfo
+	mkdir
 	mmap-shared-test
 	poweroff
+	rm
 	Shell
 	snake
 	stat

userspace/mkdir/CMakeLists.txt

@@ -0,0 +1,17 @@
+cmake_minimum_required(VERSION 3.26)
+
+project(mkdir CXX)
+
+set(SOURCES
+	main.cpp
+)
+
+add_executable(mkdir ${SOURCES})
+target_compile_options(mkdir PUBLIC -O2 -g)
+target_link_libraries(mkdir PUBLIC libc)
+
+add_custom_target(mkdir-install
+	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/mkdir ${BANAN_BIN}/
+	DEPENDS mkdir
+	USES_TERMINAL
+)

userspace/mkdir/main.cpp

@@ -0,0 +1,23 @@
+#include <stdio.h>
+#include <sys/stat.h>
+
+int main(int argc, char** argv)
+{
+	if (argc <= 1)
+	{
+		fprintf(stderr, "Missing operand\n");
+		return 1;
+	}
+
+	int ret = 0;
+	for (int i = 1; i < argc; i++)
+	{
+		if (mkdir(argv[i], 0755) == -1)
+		{
+			perror("mkdir");
+			ret = 1;
+		}
+	}
+
+	return ret;
+}

userspace/rm/CMakeLists.txt

@@ -0,0 +1,17 @@
+cmake_minimum_required(VERSION 3.26)
+
+project(rm CXX)
+
+set(SOURCES
+	main.cpp
+)
+
+add_executable(rm ${SOURCES})
+target_compile_options(rm PUBLIC -O2 -g)
+target_link_libraries(rm PUBLIC libc ban)
+
+add_custom_target(rm-install
+	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/rm ${BANAN_BIN}/
+	DEPENDS rm
+	USES_TERMINAL
+)

userspace/rm/main.cpp

@@ -0,0 +1,131 @@
+#include <BAN/String.h>
+#include <dirent.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+bool delete_recursive(const char* path)
+{
+	struct stat st;
+	if (stat(path, &st) == -1)
+	{
+		perror(path);
+		return false;
+	}
+
+	bool ret = true;
+
+	if (S_ISDIR(st.st_mode))
+	{
+		DIR* dir = opendir(path);
+		while (struct dirent* dirent = readdir(dir))
+		{
+			if (strcmp(dirent->d_name, ".") == 0 || strcmp(dirent->d_name, "..") == 0)
+				continue;
+
+			BAN::String dirent_path;
+			MUST(dirent_path.append(path));
+			MUST(dirent_path.push_back('/'));
+			MUST(dirent_path.append(dirent->d_name));
+
+			if (dirent->d_type == DT_DIR)
+			{
+				if (!delete_recursive(dirent_path.data()))
+					ret = false;
+			}
+			else
+			{
+				if (unlink(dirent_path.data()) == -1)
+				{
+					perror(dirent_path.data());
+					ret = false;
+				}
+			}
+		}
+
+		closedir(dir);
+	}
+
+	if (unlink(path) == -1)
+	{
+		perror(path);
+		return false;
+	}
+
+	return true;
+}
+
+void usage(const char* argv0, int ret)
+{
+	FILE* out = (ret == 0) ? stdout : stderr;
+	fprintf(out, "usage: %s [OPTIONS]... FILE...\n");
+	fprintf(out, "  remove each FILE\n");
+	fprintf(out, "OPTIONS:\n");
+	fprintf(out, "  -r           remove directories and their contents recursively\n");
+	fprintf(out, "  -h, --help   show this message and exit\n");
+	exit(ret);
+}
+
+int main(int argc, char** argv)
+{
+	bool recursive = false;
+
+	int i = 1;
+	for (; i < argc; i++)
+	{
+		if (argv[i][0] != '-')
+			break;
+
+		if (strcmp(argv[i], "-r") == 0)
+			recursive = true;
+		else if (strcmp(argv[i], "-h") == 0 || strcmp(argv[i], "--help") == 0)
+			usage(argv[0], 0);
+		else
+		{
+			fprintf(stderr, "unrecognized argument %s. use --help for more information\n", argv[i]);
+			return 1;
+		}
+	}
+
+	if (i >= argc)
+	{
+		fprintf(stderr, "missing operand. use --help for more information\n");
+		return 1;
+	}
+
+	int ret = 0;
+	for (; i < argc; i++)
+	{
+		if (recursive)
+		{
+			if (!delete_recursive(argv[i]))
+				ret = 1;
+		}
+		else
+		{
+			struct stat st;
+			if (stat(argv[i], &st) == -1)
+			{
+				perror(argv[i]);
+				ret = 1;
+				continue;
+			}
+			
+			if (S_ISDIR(st.st_mode))
+			{
+				fprintf(stderr, "%s: %s\n", argv[i], strerror(EISDIR));
+				ret = 1;
+				continue;
+			}
+
+			if (unlink(argv[i]) == -1)
+			{
+				perror(argv[i]);
+				ret = 1;
+			}
+		}
+	}
+	return ret;
+}

userspace/touch/main.cpp

@@ -4,18 +4,14 @@
 
 int main(int argc, char** argv)
 {
+	int ret = 0;
 	for (int i = 1; i < argc; i++)
 	{
-		int fd = open(argv[i], O_WRONLY | O_CREAT, 0644);
+		if (creat(argv[i], 0644) == -1 && errno != EEXIST)
-		if (fd == -1)
 		{
-			if (errno != EEXISTS)
 			perror(argv[i]);
-		}
+			ret = 1;
-		else
-		{
-			close(fd);
 		}
 	}
-	return 0;
+	return ret;
 }