meminfo: Add process command line to the output

gcc seems to optimize some calls to strcpy to stpcpy

.gitignore

@@ -1,7 +1,8 @@
-*.img
-isodir
-sysroot
 .vscode/
 .idea/
-bochsrc
-bx_enh_dbg.ini
+build/
+base/
+*.tar.*
+toolchain/*/
+
+!base-sysroot.tar.gz

.gitmodules

@@ -0,0 +1,4 @@
+[submodule "kernel/lai"]
+	path = kernel/lai
+	url = https://github.com/managarm/lai.git
+	ignore = untracked

BAN/BAN/Memory.cpp

@@ -1,9 +0,0 @@
-#include <BAN/Memory.h>
-
-void* operator new(size_t size)								{ return BAN::allocator(size); }
-void* operator new[](size_t size)							{ return BAN::allocator(size); }
-
-void operator delete(void* addr)							{ BAN::deallocator(addr); }
-void operator delete[](void* addr)							{ BAN::deallocator(addr); }
-void operator delete(void* addr, size_t)					{ BAN::deallocator(addr); }
-void operator delete[](void* addr, size_t)					{ BAN::deallocator(addr); }

BAN/BAN/New.cpp

@@ -0,0 +1,9 @@
+#include <BAN/New.h>
+
+void* operator new(size_t size)				{ return BAN::allocator(size); }
+void* operator new[](size_t size)			{ return BAN::allocator(size); }
+
+void operator delete(void* addr)				{ BAN::deallocator(addr); }
+void operator delete[](void* addr)			{ BAN::deallocator(addr); }
+void operator delete(void* addr, size_t)		{ BAN::deallocator(addr); }
+void operator delete[](void* addr, size_t)	{ BAN::deallocator(addr); }

BAN/BAN/String.cpp

@@ -1,7 +1,7 @@
 #include <BAN/Errors.h>
 #include <BAN/Math.h>
-#include <BAN/Memory.h>
 #include <BAN/Move.h>
+#include <BAN/New.h>
 #include <BAN/String.h>
 #include <BAN/StringView.h>
 
@@ -119,7 +119,7 @@ namespace BAN
 		m_size -= count;
 		m_data[m_size] = '\0';
 	}
-	
+
 	void String::clear()
 	{
 		m_size = 0;

BAN/BAN/StringView.cpp

@@ -63,9 +63,38 @@ namespace BAN
 
 	ErrorOr<Vector<StringView>> StringView::split(char delim, bool allow_empties)
 	{
-		// FIXME: Won't work while multithreading
-		static char s_delim = delim;
-		return split([](char c){ return c == s_delim; }, allow_empties);
+		size_type count = 0;
+		{
+			size_type start = 0;
+			for (size_type i = 0; i < m_size; i++)
+			{
+				if (m_data[i] == delim)
+				{
+					if (allow_empties || start != i)
+						count++;
+					start = i + 1;
+				}
+			}
+			if (start != m_size)
+				count++;
+		}
+
+		Vector<StringView> result;
+		TRY(result.reserve(count));
+
+		size_type start = 0;
+		for (size_type i = 0; i < m_size; i++)
+		{
+			if (m_data[i] == delim)
+			{
+				if (allow_empties || start != i)
+					TRY(result.push_back(this->substring(start, i - start)));
+				start = i + 1;
+			}
+		}
+		if (start != m_size)
+			TRY(result.push_back(this->substring(start)));
+		return result;
 	}
 
 	ErrorOr<Vector<StringView>> StringView::split(bool(*comp)(char), bool allow_empties)
@@ -116,6 +145,14 @@ namespace BAN
 		return m_data[0];
 	}
 
+	bool StringView::contains(char ch) const
+	{
+		for (size_type i = 0; i < m_size; i++)
+			if (m_data[i] == ch)
+				return true;
+		return false;
+	}
+
 	StringView::size_type StringView::count(char ch) const
 	{
 		size_type result = 0;
@@ -134,7 +171,7 @@ namespace BAN
 	{
 		return m_size;
 	}
-	
+
 	const char* StringView::data() const
 	{
 		return m_data;

BAN/BAN/Time.cpp

@@ -0,0 +1,71 @@
+#include <BAN/Time.h>
+
+namespace BAN
+{
+
+	static constexpr bool is_leap_year(uint64_t year)
+	{
+		if (year % 400 == 0)
+			return true;
+		if (year % 100 == 0)
+			return false;
+		if (year % 4 == 0)
+			return true;
+		return false;
+	}
+
+	static constexpr uint64_t leap_days_since_epoch(const BAN::Time& time)
+	{
+		uint64_t leap_years = 0;
+		for (uint32_t year = 1970; year < time.year; year++)
+			if (is_leap_year(year))
+				leap_years++;
+		if (is_leap_year(time.year) && time.month >= 3)
+			leap_years++;
+		return leap_years;
+	}
+
+	static constexpr uint64_t month_days[] { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
+
+	uint64_t to_unix_time(const BAN::Time& time)
+	{
+		uint64_t years = time.year - 1970;
+		uint64_t days = years * 365 + month_days[time.month - 1] + leap_days_since_epoch(time) + (time.day - 1);
+		uint64_t hours = days * 24 + time.hour;
+		uint64_t minutes = hours * 60 + time.minute;
+		uint64_t seconds = minutes * 60 + time.second;
+		return seconds;
+	}
+
+	BAN::Time from_unix_time(uint64_t unix_time)
+	{		
+		BAN::Time time {};
+
+		time.second = unix_time % 60; unix_time /= 60;
+		time.minute = unix_time % 60; unix_time /= 60;
+		time.hour   = unix_time % 24; unix_time /= 24;
+
+		uint64_t total_days = unix_time;
+
+		time.week_day = (total_days + 4) % 7 + 1;
+
+		time.year = 1970;
+		while (total_days >= 365U + is_leap_year(time.year))
+		{
+			total_days -= 365U + is_leap_year(time.year);
+			time.year++;
+		}
+
+		bool is_leap_day = is_leap_year(time.year) && total_days == month_days[2];
+		bool had_leap_day = is_leap_year(time.year) && total_days > month_days[2];
+
+		for (time.month = 1; time.month < 12; time.month++)
+			if (total_days < month_days[time.month] + (is_leap_day || had_leap_day))
+				break;
+
+		time.day = total_days - month_days[time.month - 1] + !had_leap_day;
+
+		return time;
+	}
+
+}

BAN/CMakeLists.txt

@@ -0,0 +1,26 @@
+cmake_minimum_required(VERSION 3.26)
+
+project(BAN CXX)
+
+set(BAN_SOURCES
+	BAN/New.cpp
+	BAN/String.cpp
+	BAN/StringView.cpp
+	BAN/Time.cpp
+)
+
+add_custom_target(ban-headers
+	COMMAND sudo rsync -a ${CMAKE_CURRENT_SOURCE_DIR}/include/ ${BANAN_INCLUDE}/
+	DEPENDS sysroot
+	USES_TERMINAL
+)
+
+add_library(ban ${BAN_SOURCES})
+add_dependencies(ban headers libc-install)
+
+add_custom_target(ban-install
+	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/libban.a ${BANAN_LIB}/
+	DEPENDS ban
+	BYPRODUCTS ${BANAN_LIB}/libban.a
+	USES_TERMINAL
+)

BAN/Makefile

@@ -1,89 +0,0 @@
-DEFAULT_HOST!=../default-host.sh
-HOST?=DEFAULT_HOST
-HOSTARCH!=../target-triplet-to-arch.sh $(HOST)
- 
-CFLAGS?=-O2 -g
-CPPFLAGS?=
-LDFLAGS?=
-LIBS?=
- 
-DESTDIR?=
-PREFIX?=/usr/local
-EXEC_PREFIX?=$(PREFIX)
-INCLUDEDIR?=$(PREFIX)/include
-LIBDIR?=$(EXEC_PREFIX)/lib
- 
-CFLAGS:=$(CFLAGS) -Iinclude -ffreestanding -Wall -Wextra -Werror=return-type
-CPPFLAGS:=$(CPPFLAGS)
-LIBBANK_CFLAGS:=$(CFLAGS) -D__is_kernel -Iinclude -ffreestanding -Wall -Wextra
-LIBBANK_CPPFLAGS:=$(CPPFLAGS) -fno-rtti -fno-exceptions
- 
-ARCHDIR=arch/$(HOSTARCH)
- 
-include $(ARCHDIR)/make.config
- 
-CFLAGS:=$(CFLAGS) $(ARCH_CFLAGS)
-CPPFLAGS:=$(CPPFLAGS) $(ARCH_CPPFLAGS)
-LIBBANK_CFLAGS:=$(LIBBANK_CFLAGS) $(KERNEL_ARCH_CFLAGS)
-LIBBANK_CPPFLAGS:=$(LIBBANK_CPPFLAGS) $(KERNEL_ARCH_CPPFLAGS)
- 
-BUILDDIR=$(abspath build)
- 
-FREEOBJS=			\
-$(ARCH_FREEOBJS)	\
-BAN/Memory.o		\
-BAN/String.o		\
-BAN/StringView.o	\
- 
-HOSTEDOBJS=\
-$(ARCH_HOSTEDOBJS) \
- 
-OBJS=\
-$(FREEOBJS) \
-$(HOSTEDOBJS) \
- 
-LIBBANK_OBJS=$(FREEOBJS:.o=.bank.o)
- 
-BINARIES=libbank.a
- 
-.PHONY: all always clean install install-headers install-libs
-.SUFFIXES: .o .bank.o .cpp .S
- 
-all: $(BINARIES)
- 
-libban.a: always $(OBJS)
-	cd $(BUILDDIR) && $(AR) rcs $@ $(OBJS)
- 
-libbank.a: always $(LIBBANK_OBJS)
-	cd $(BUILDDIR) && $(AR) rcs $@ $(LIBBANK_OBJS)
- 
-.cpp.o:
-	$(CXX) -MD -c $< -o $(BUILDDIR)/$@ $(CFLAGS) $(CPPFLAGS)
- 
-.S.o:
-	$(CXX) -MD -c $< -o $(BUILDDIR)/$@ $(CFLAGS) $(CPPFLAGS)
- 
-.cpp.bank.o:
-	$(CXX) -MD -c $< -o $(BUILDDIR)/$@ $(LIBBANK_CFLAGS) $(LIBBANK_CPPFLAGS)
- 
-.S.bank.o:
-	$(CXX) -MD -c $< -o $(BUILDDIR)/$@ $(LIBBANK_CFLAGS) $(LIBBANK_CPPFLAGS)
- 
-clean:
-	rm -rf $(BUILDDIR)
- 
-always:
-	mkdir -p $(BUILDDIR)/BAN
- 
-install: install-headers install-libs
- 
-install-headers:
-	mkdir -p $(DESTDIR)$(INCLUDEDIR)
-	cp -R --preserve=timestamps include/. $(DESTDIR)$(INCLUDEDIR)/.
- 
-install-libs: $(BINARIES)
-	mkdir -p $(DESTDIR)$(LIBDIR)
-	cp $(BUILDDIR)/$(BINARIES) $(DESTDIR)$(LIBDIR)
- 
--include $(OBJS:.o=.d)
--include $(LIBBANK_OBJS:.o=.d)

BAN/arch/i386/make.config

@@ -1,8 +0,0 @@
-ARCH_CFLAGS=
-ARCH_CPPFLAGS=
-KERNEL_ARCH_CFLAGS=
-KERNEL_ARCH_CPPFLAGS=
- 
-ARCH_FREEOBJS=\
- 
-ARCH_HOSTEDOBJS=\

BAN/arch/x86_64/make.config

@@ -1,8 +0,0 @@
-ARCH_CFLAGS=
-ARCH_CPPFLAGS=
-KERNEL_ARCH_CFLAGS=
-KERNEL_ARCH_CPPFLAGS=
- 
-ARCH_FREEOBJS=\
- 
-ARCH_HOSTEDOBJS=\

BAN/include/BAN/Array.h

@@ -1,6 +1,8 @@
 #pragma once
 
 #include <BAN/Errors.h>
+#include <BAN/Iterators.h>
+#include <BAN/Span.h>
 
 #include <stddef.h>
 
@@ -13,11 +15,18 @@ namespace BAN
 	public:
 		using size_type = decltype(S);
 		using value_type = T;
+		using iterator = IteratorSimple<T, Array>;
+		using const_iterator = ConstIteratorSimple<T, Array>;
 
 	public:
 		Array();
 		Array(const T&);
 
+		iterator begin() { return iterator(m_data); }
+		iterator end() { return iterator(m_data + size()); }
+		const_iterator begin() const { return const_iterator(m_data); }
+		const_iterator end() const { return const_iterator(m_data + size()); }
+
 		const T& operator[](size_type) const;
 		T& operator[](size_type);
 
@@ -26,7 +35,13 @@ namespace BAN
 		const T& front() const;
 		T& front();
 
+		Span<T> span() { return Span(m_data, size()); }
+		const Span<T> span() const { return Span(m_data, size()); }
+
 		constexpr size_type size() const;
+		
+		const T* data() const { return m_data; }
+		T* data() { return m_data; }
 
 	private:
 		T m_data[S];

BAN/include/BAN/Assert.h

@@ -2,10 +2,10 @@
 
 #if defined(__is_kernel)
 	#include <kernel/Panic.h>
-	#define ASSERT(cond) do { if (!(cond)) Kernel::panic("ASSERT("#cond") failed"); } while(false)
+	#define ASSERT(cond) do { if (!(cond)) Kernel::panic("ASSERT("#cond") failed"); } while (false)
 	#define ASSERT_NOT_REACHED() Kernel::panic("ASSERT_NOT_REACHED() failed")
 #else
 	#include <assert.h>
 	#define ASSERT(cond) assert((cond) && "ASSERT("#cond") failed")
-	#define ASSERT_NOT_REACHED() assert(false && "ASSERT_NOT_REACHED() failed")
+	#define ASSERT_NOT_REACHED() do { assert(false && "ASSERT_NOT_REACHED() failed"); __builtin_unreachable(); } while (false)
 #endif

BAN/include/BAN/CircularQueue.h

@@ -0,0 +1,113 @@
+#pragma once
+
+#include <BAN/Assert.h>
+
+#include <stdint.h>
+#include <stddef.h>
+
+namespace BAN
+{
+
+	template<typename T, size_t S>
+	class CircularQueue
+	{
+	public:
+		using size_type = size_t;
+		using value_type = T;
+
+	public:
+		CircularQueue() = default;
+		~CircularQueue();
+
+		void push(const T&);
+		void push(T&&);
+		template<typename... Args>
+		void emplace(Args&&... args);
+
+		void pop();
+
+		const T& front() const;
+		T& front();
+
+		size_type size() const { return m_size; }
+		bool empty() const { return size() == 0; }
+		bool full() const { return size() == capacity(); }
+		
+		static constexpr size_type capacity() { return S; }
+
+	private:
+		T* element_at(size_type);
+		const T* element_at(size_type) const;
+
+	private:
+		alignas(T) uint8_t m_storage[sizeof(T) * capacity()];
+		size_type m_first { 0 };
+		size_type m_size { 0 };
+	};
+
+	template<typename T, size_t S>
+	CircularQueue<T, S>::~CircularQueue()
+	{
+		for (size_type i = 0; i < m_size; i++)
+			element_at((m_first + i) % capacity())->~T();
+	}
+
+	template<typename T, size_t S>
+	void CircularQueue<T, S>::push(const T& value)
+	{
+		emplace(BAN::move(T(value)));
+	}
+
+	template<typename T, size_t S>
+	void CircularQueue<T, S>::push(T&& value)
+	{
+		emplace(BAN::move(value));
+	}
+
+	template<typename T, size_t S>
+	template<typename... Args>
+	void CircularQueue<T, S>::emplace(Args&&... args)
+	{
+		ASSERT(!full());
+		new (element_at(((m_first + m_size) % capacity()))) T(BAN::forward<Args>(args)...);
+		m_size++;
+	}
+
+	template<typename T, size_t S>
+	void CircularQueue<T, S>::pop()
+	{
+		ASSERT(!empty());
+		element_at(m_first)->~T();
+		m_first = (m_first + 1) % capacity();
+		m_size--;
+	}
+
+	template<typename T, size_t S>
+	const T& CircularQueue<T, S>::front() const
+	{
+		ASSERT(!empty());
+		return *element_at(m_first);
+	}
+
+	template<typename T, size_t S>
+	T& CircularQueue<T, S>::front()
+	{
+		ASSERT(!empty());
+		return *element_at(m_first);
+	}
+
+	template<typename T, size_t S>
+	const T* CircularQueue<T, S>::element_at(size_type index) const
+	{
+		ASSERT(index < capacity());
+		return (const T*)(m_storage + index * sizeof(T));
+	}
+
+	template<typename T, size_t S>
+	T* CircularQueue<T, S>::element_at(size_type index)
+	{
+		ASSERT(index < capacity());
+		return (T*)(m_storage + index * sizeof(T));
+	}
+
+}

BAN/include/BAN/Endianness.h

@@ -0,0 +1,80 @@
+#pragma once
+
+#include <BAN/Traits.h>
+
+#include <stddef.h>
+
+namespace BAN
+{
+
+	template<integral T>
+	constexpr T swap_endianness(T value)
+	{
+		if constexpr(sizeof(T) == 1)
+			return value;
+		if constexpr(sizeof(T) == 2)
+			return (((value >> 8) & 0xFF) << 0)
+				 | (((value >> 0) & 0xFF) << 8);
+		if constexpr(sizeof(T) == 4)
+			return (((value >> 24) & 0xFF) <<  0)
+				 | (((value >> 16) & 0xFF) <<  8)
+				 | (((value >>  8) & 0xFF) << 16)
+				 | (((value >>  0) & 0xFF) << 24);
+		if constexpr(sizeof(T) == 8)
+			return (((value >> 56) & 0xFF) <<  0)
+				 | (((value >> 48) & 0xFF) <<  8)
+				 | (((value >> 40) & 0xFF) << 16)
+				 | (((value >> 32) & 0xFF) << 24)
+				 | (((value >> 24) & 0xFF) << 32)
+				 | (((value >> 16) & 0xFF) << 40)
+				 | (((value >>  8) & 0xFF) << 48)
+				 | (((value >>  0) & 0xFF) << 56);
+		T result { 0 };
+		for (size_t i = 0; i < sizeof(T); i++)
+			result |= ((value >> (i * 8)) & 0xFF) << ((sizeof(T) - i - 1) * 8);
+		return result;
+	}
+
+	template<integral T>
+	constexpr T host_to_little_endian(T value)
+	{
+#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+		return value;
+#else
+		return swap_endianness(value);
+#endif
+	}
+
+	template<integral T>
+	constexpr T host_to_big_endian(T value)
+	{
+#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+		return value;
+#else
+		return swap_endianness(value);
+#endif
+	}
+
+	template<integral T>
+	struct LittleEndian
+	{
+		constexpr operator T() const
+		{
+			return host_to_little_endian(raw);
+		}
+	private:
+		T raw;
+	};
+
+	template<integral T>
+	struct BigEndian
+	{
+		constexpr operator T() const
+		{
+			return host_to_big_endian(raw);
+		}
+	private:
+		T raw;
+	};
+
+}

BAN/include/BAN/Errors.h

@@ -1,62 +1,76 @@
 #pragma once
 
 #include <BAN/Formatter.h>
+#include <BAN/StringView.h>
 #include <BAN/Variant.h>
 
 #include <errno.h>
 #include <string.h>
 
-#if defined(__is_kernel)
+#ifdef __is_kernel
 	#include <kernel/Panic.h>
-	#define MUST(expr)	({ auto e = expr; if (e.is_error()) Kernel::panic("{}", e.error()); e.release_value(); })
+	#include <kernel/Errors.h>
+	#define MUST(expr)		 ({ auto&& e = expr; if (e.is_error()) Kernel::panic("{}", e.error()); e.release_value(); })
+	#define MUST_REF(expr)	*({ auto&& e = expr; if (e.is_error()) Kernel::panic("{}", e.error()); &e.release_value(); })
 #else
-	#define MUST(expr)	({ auto e = expr; assert(!e.is_error()); e.release_value(); })
+	#include <assert.h>
+	#define MUST(expr)		 ({ auto&& e = expr; assert(!e.is_error()); e.release_value(); })
+	#define MUST_REF(expr)	*({ auto&& e = expr; assert(!e.is_error()); &e.release_value(); })
 #endif
 
-#define TRY(expr) ({ auto e = expr; if (e.is_error()) return e.release_error(); e.release_value(); })
+#define TRY(expr)		 ({ auto&& e = expr; if (e.is_error()) return e.release_error(); e.release_value(); })
+#define TRY_REF(expr)	*({ auto&& e = expr; if (e.is_error()) return e.release_error(); &e.release_value(); })
 
 namespace BAN
 {
 
 	class Error
 	{
+#ifdef __is_kernel
+	private:
+		static constexpr uint64_t kernel_error_mask = uint64_t(1) << 63;
+#endif
+
 	public:
-		static Error from_c_string(const char* message)
+#ifdef __is_kernel
+		static Error from_error_code(Kernel::ErrorCode error)
 		{
-			Error result;
-			strncpy(result.m_message, message, sizeof(Error::m_message));
-			result.m_message[sizeof(Error::m_message) - 1] = '\0';
-			result.m_error_code = 0xFF;
-			return result;
-		}
-		template<typename... Args>
-		static Error from_format(const char* format, Args&&... args)
-		{
-			char buffer[sizeof(Error::m_message)] {};
-			size_t index = 0;
-			auto putc = [&](char ch)
-			{
-				if (index < sizeof(buffer) - 1)
-					buffer[index++] = ch;
-			};
-			Formatter::print(putc, format, forward<Args>(args)...);
-			return from_c_string(buffer);
+			return Error((uint64_t)error | kernel_error_mask);
 		}
+#endif
 		static Error from_errno(int error)
 		{
-			Error result;
-			strncpy(result.m_message, strerror(error), sizeof(Error::m_message));
-			result.m_message[sizeof(Error::m_message) - 1] = '\0';
-			result.m_error_code = error;
-			return result;
+			return Error(error);
 		}
 
-		uint8_t get_error_code() const { return m_error_code; }
-		const char* get_message() const { return m_message; }
+#ifdef __is_kernel
+		Kernel::ErrorCode kernel_error() const
+		{
+			return (Kernel::ErrorCode)(m_error_code & ~kernel_error_mask);
+		}
+
+		bool is_kernel_error() const
+		{
+			return m_error_code & kernel_error_mask;
+		}
+#endif
+
+		uint64_t get_error_code() const { return m_error_code; }
+		BAN::StringView get_message() const
+		{
+#ifdef __is_kernel
+			if (m_error_code & kernel_error_mask)
+				return Kernel::error_string(kernel_error());
+#endif
+			return strerror(m_error_code);
+		}
 
 	private:
-		char m_message[128];
-		uint8_t m_error_code;
+		Error(uint64_t error)
+			: m_error_code(error)
+		{}
+
+		uint64_t m_error_code;
 	};
 
 	template<typename T>
@@ -76,19 +90,46 @@ namespace BAN
 			: m_data(move(error))
 		{}
 
-		bool is_error() const			{ return m_data.template is<Error>(); }
+		bool is_error() const			{ return m_data.template has<Error>(); }
 		const Error& error() const		{ return m_data.template get<Error>(); }
 		Error& error()					{ return m_data.template get<Error>(); }
 		const T& value() const			{ return m_data.template get<T>(); }
 		T& value()						{ return m_data.template get<T>(); }
 
-		Error release_error()				{ return move(error()); m_data.clear(); }
+		Error release_error()			{ return move(error()); m_data.clear(); }
 		T release_value()				{ return move(value()); m_data.clear(); }
 
 	private:
 		Variant<Error, T> m_data;
 	};
 
+	template<lvalue_reference T>
+	class [[nodiscard]] ErrorOr<T>
+	{
+	public:
+		ErrorOr(T value)
+		{
+			m_data.template set<T>(value);
+		}
+		ErrorOr(Error&& error)
+			: m_data(move(error))
+		{ }
+		ErrorOr(const Error& error)
+			: m_data(error)
+		{ }
+
+		bool is_error() const			{ return m_data.template has<Error>(); }
+		Error& error()					{ return m_data.template get<Error>(); }
+		const Error& error() const		{ return m_data.template get<Error>(); }
+		T value()						{ return m_data.template get<T>(); }
+
+		Error release_error()			{ return move(error()); m_data.clear(); }
+		T release_value()				{ return value(); m_data.clear(); }
+
+	private:
+		Variant<Error, T> m_data;
+	};
+
 	template<>
 	class [[nodiscard]] ErrorOr<void>
 	{
@@ -102,12 +143,12 @@ namespace BAN
 		const Error& error() const		{ return m_data; }
 		void value()					{ }
 
-		Error release_error()			{ return move(m_data); m_data = Error(); }
-		void release_value()			{ m_data = Error(); }
+		Error release_error()			{ return move(m_data); }
+		void release_value()			{ }
 
 	private:
-		Error m_data;
-		bool m_has_error = false;
+		Error m_data { Error::from_errno(0) };
+		bool m_has_error { false };
 	};
 
 }
@@ -115,11 +156,8 @@ namespace BAN
 namespace BAN::Formatter
 {
 	template<typename F>
-	void print_argument(F putc, const Error& error, const ValueFormat&)
+	void print_argument(F putc, const Error& error, const ValueFormat& format)
 	{
-		if (error.get_error_code() == 0xFF)
-			print(putc, error.get_message());
-		else
-			print(putc, "{} ({})", error.get_message(), error.get_error_code());
+		print_argument(putc, error.get_message(), format);
 	}
 }

BAN/include/BAN/Formatter.h

@@ -28,9 +28,8 @@ namespace BAN::Formatter
 		static size_t parse_format_and_print_argument(F putc, const char* format, T&& arg);
 	}
 
-
 	/*
-	
+
 		IMPLEMENTATION
 
 	*/
@@ -42,7 +41,7 @@ namespace BAN::Formatter
 		int fill		= 0;
 		bool upper		= false;
 	};
-	
+
 	template<typename F>
 	void print(F putc, const char* format)
 	{
@@ -232,7 +231,7 @@ namespace BAN::Formatter
 	}
 
 	/*
-	
+
 		TEMPLATE SPECIALIZATIONS
 
 	*/
@@ -243,10 +242,7 @@ namespace BAN::Formatter
 
 	template<typename F> void print_argument(F putc, char			value, const ValueFormat&)	{ putc(value); }
 	template<typename F> void print_argument(F putc, bool			value, const ValueFormat&)	{ print(putc, value ? "true" : "false"); }
-	template<typename F> void print_argument(F putc, const char*	value, const ValueFormat&)	{ print(putc, value);}
-	
-	//template<typename F> void print_argument(F putc, signed char			value, const ValueFormat& format)	{ detail::print_integer(putc, value, format); }
-	//template<typename F> void print_argument(F putc, unsigned char			value, const ValueFormat& format)	{ detail::print_integer(putc, value, format); }
-	//template<typename F, typename T> void print_argument(F putc, T*			value, const ValueFormat& format)	{ detail::print_pointer(putc, (void*)value, format); }
+	template<typename F> void print_argument(F putc, const char*	value, const ValueFormat&)	{ print(putc, value); }
+	template<typename F> void print_argument(F putc, char*			value, const ValueFormat&)	{ print(putc, value); }
 
 }

BAN/include/BAN/ForwardList.h

@@ -5,7 +5,7 @@
 namespace BAN
 {
 
-	
+
 	template<typename, size_t> class Array;
 	template<typename> class ErrorOr;
 	template<typename> class Function;

BAN/include/BAN/Function.h

@@ -2,7 +2,7 @@
 
 #include <BAN/Errors.h>
 #include <BAN/Move.h>
-#include <BAN/Memory.h>
+#include <BAN/New.h>
 
 namespace BAN
 {
@@ -43,10 +43,10 @@ namespace BAN
 			clear();
 		}
 
-		Ret operator()(Args... args)
+		Ret operator()(Args... args) const
 		{
 			ASSERT(*this);
-			return reinterpret_cast<CallableBase*>(m_storage)->call(forward<Args>(args)...);
+			return reinterpret_cast<const CallableBase*>(m_storage)->call(forward<Args>(args)...);
 		}
 
 		operator bool() const
@@ -70,7 +70,7 @@ namespace BAN
 		struct CallableBase
 		{
 			virtual ~CallableBase() {}
-			virtual Ret call(Args...) = 0;
+			virtual Ret call(Args...) const = 0;
 		};
 
 		struct CallablePointer : public CallableBase
@@ -79,7 +79,7 @@ namespace BAN
 				: m_function(function)
 			{ }
 
-			virtual Ret call(Args... args) override
+			virtual Ret call(Args... args) const override
 			{
 				return m_function(forward<Args>(args)...);
 			}
@@ -96,7 +96,7 @@ namespace BAN
 				, m_function(function)
 			{ }
 
-			virtual Ret call(Args... args) override
+			virtual Ret call(Args... args) const override
 			{
 				return (m_owner->*m_function)(forward<Args>(args)...);
 			}
@@ -114,7 +114,7 @@ namespace BAN
 				, m_function(function)
 			{ }
 
-			virtual Ret call(Args... args) override
+			virtual Ret call(Args... args) const override
 			{
 				return (m_owner->*m_function)(forward<Args>(args)...);
 			}
@@ -131,7 +131,7 @@ namespace BAN
 				: m_lambda(lambda)
 			{ }
 
-			virtual Ret call(Args... args) override
+			virtual Ret call(Args... args) const override
 			{
 				return m_lambda(forward<Args>(args)...);
 			}
@@ -141,7 +141,7 @@ namespace BAN
 		};
 
 	private:
-		static constexpr size_t m_size = sizeof(void*) * 4;
+		static constexpr size_t m_size = sizeof(void*) * 5;
 		alignas(CallableBase) uint8_t m_storage[m_size] { 0 };
 	};
 

BAN/include/BAN/HashMap.h

@@ -7,13 +7,31 @@
 namespace BAN
 {
 
+	template<typename Container>
+	class HashMapIterator;
+
 	template<typename Key, typename T, typename HASH = BAN::hash<Key>>
 	class HashMap
 	{
+	public:
+		struct Entry
+		{
+			template<typename... Args>
+			Entry(const Key& key, Args&&... args)
+				: key(key)
+				, value(forward<Args>(args)...)
+			{}
+
+			Key key;
+			T value;
+		};
+
 	public:
 		using size_type = size_t;
 		using key_type = Key;
 		using value_type = T;
+		using iterator = IteratorDouble<Entry, Vector, LinkedList, HashMap>;
+		using const_iterator = ConstIteratorDouble<Entry, Vector, LinkedList, HashMap>;
 
 	public:
 		HashMap() = default;
@@ -29,6 +47,11 @@ namespace BAN
 		template<typename... Args>
 		ErrorOr<void> emplace(const Key&, Args&&...);
 
+		iterator begin() { return iterator(m_buckets.end(), m_buckets.begin()); }
+		iterator end()   { return iterator(m_buckets.end(), m_buckets.end()); }
+		const_iterator begin() const { return const_iterator(m_buckets.end(), m_buckets.begin()); }
+		const_iterator end() const   { return const_iterator(m_buckets.end(), m_buckets.end()); }
+
 		ErrorOr<void> reserve(size_type);
 
 		void remove(const Key&);
@@ -42,19 +65,6 @@ namespace BAN
 		bool empty() const;
 		size_type size() const;
 
-	private:
-		struct Entry
-		{
-			template<typename... Args>
-			Entry(const Key& key, Args&&... args)
-				: key(key)
-				, value(forward<Args>(args)...)
-			{}
-
-			Key key;
-			T value;
-		};
-
 	private:
 		ErrorOr<void> rebucket(size_type);
 		LinkedList<Entry>& get_bucket(const Key&);
@@ -63,6 +73,8 @@ namespace BAN
 	private:
 		Vector<LinkedList<Entry>> m_buckets;
 		size_type m_size = 0;
+
+		friend iterator;
 	};
 
 	template<typename Key, typename T, typename HASH>
@@ -246,4 +258,4 @@ namespace BAN
 		return m_buckets[index];
 	}
 
-}
+}

BAN/include/BAN/HashSet.h

@@ -85,8 +85,6 @@ namespace BAN
 		friend class HashSet<T, HASH>;
 	};
 
-
-
 	template<typename T, typename HASH>
 	HashSet<T, HASH>::HashSet(const HashSet<T, HASH>& other)
 		: m_buckets(other.m_buckets)
@@ -231,8 +229,6 @@ namespace BAN
 		return m_buckets[index];
 	}
 
-
-
 	template<typename T, typename HASH>
 	HashSetIterator<T, HASH>& HashSetIterator<T, HASH>::operator++()
 	{

BAN/include/BAN/Iteration.h

@@ -0,0 +1,12 @@
+#pragma once
+
+namespace BAN
+{
+
+	enum class Iteration
+	{
+		Continue,
+		Break
+	};
+
+}

BAN/include/BAN/Iterators.h

@@ -0,0 +1,229 @@
+#pragma once
+
+#include <BAN/Assert.h>
+
+namespace BAN
+{
+
+	template<typename T, typename Container, bool CONST>
+	class IteratorSimpleGeneral
+	{
+	public:
+		IteratorSimpleGeneral() = default;
+		template<bool CONST2, typename = enable_if_t<CONST2 == CONST || CONST>>
+		IteratorSimpleGeneral(const IteratorSimpleGeneral<T, Container, CONST2>& other)
+			: m_pointer(other.m_pointer)
+		{
+		}
+
+		const T& operator*() const
+		{
+			ASSERT(m_pointer);
+			return *m_pointer;
+		}
+		template<bool CONST2 = CONST>
+		enable_if_t<!CONST2, T&> operator*()
+		{
+			ASSERT(m_pointer);
+			return *m_pointer;
+		}
+
+		const T* operator->() const
+		{
+			ASSERT(m_pointer);
+			return m_pointer;
+		}
+		template<bool CONST2 = CONST>
+		enable_if_t<!CONST2, T*> operator->()
+		{
+			ASSERT(m_pointer);
+			return m_pointer;
+		}
+
+		IteratorSimpleGeneral& operator++()
+		{
+			ASSERT(m_pointer);
+			++m_pointer;
+			return *this;
+		}
+		IteratorSimpleGeneral operator++(int)
+		{
+			auto temp = *this;
+			++(*this);
+			return temp;
+		}
+
+		IteratorSimpleGeneral& operator--()
+		{
+			ASSERT(m_pointer);
+			return --m_pointer;
+		}
+		IteratorSimpleGeneral operator--(int)
+		{
+			auto temp = *this;
+			--(*this);
+			return temp;
+		}
+
+		bool operator==(const IteratorSimpleGeneral& other) const
+		{
+			return m_pointer == other.m_pointer;
+		}
+		bool operator!=(const IteratorSimpleGeneral& other) const
+		{
+			return !(*this == other);
+		}
+
+		operator bool() const
+		{
+			return m_pointer;
+		}
+
+	private:
+		IteratorSimpleGeneral(maybe_const_t<CONST, T>* pointer)
+			: m_pointer(pointer)
+		{
+		}
+
+	private:
+		maybe_const_t<CONST, T>* m_pointer = nullptr;
+
+		friend IteratorSimpleGeneral<T, Container, !CONST>;
+		friend Container;
+	};
+
+	template<typename T, template<typename> typename OuterContainer, template<typename> typename InnerContainer, typename Container, bool CONST>
+	class IteratorDoubleGeneral
+	{
+	public:
+		using Inner = InnerContainer<T>;
+		using Outer = OuterContainer<Inner>;
+
+		using InnerIterator = either_or_t<CONST, typename Inner::const_iterator, typename Inner::iterator>;
+		using OuterIterator = either_or_t<CONST, typename Outer::const_iterator, typename Outer::iterator>;
+
+	public:
+		IteratorDoubleGeneral() = default;
+		template<bool CONST2, typename = enable_if_t<CONST2 == CONST || CONST>>
+		IteratorDoubleGeneral(const IteratorDoubleGeneral<T, OuterContainer, InnerContainer, Container, CONST2>& other)
+			: m_outer_end(other.m_outer_end)
+			, m_outer_current(other.m_outer_current)
+			, m_inner_current(other.m_inner_current)
+		{
+		}
+
+		const T& operator*() const
+		{
+			ASSERT(*this);
+			ASSERT(m_outer_current != m_outer_end);
+			ASSERT(m_inner_current);
+			return m_inner_current.operator*();
+		}
+		template<bool CONST2 = CONST>
+		enable_if_t<!CONST2, T&> operator*()
+		{
+			ASSERT(*this);
+			ASSERT(m_outer_current != m_outer_end);
+			ASSERT(m_inner_current);
+			return m_inner_current.operator*();
+		}
+
+		const T* operator->() const
+		{
+			ASSERT(*this);
+			ASSERT(m_outer_current != m_outer_end);
+			ASSERT(m_inner_current);
+			return m_inner_current.operator->();
+		}
+		template<bool CONST2 = CONST>
+		enable_if_t<!CONST2, T*> operator->()
+		{
+			ASSERT(*this);
+			ASSERT(m_outer_current != m_outer_end);
+			ASSERT(m_inner_current);
+			return m_inner_current.operator->();
+		}
+
+		IteratorDoubleGeneral& operator++()
+		{
+			ASSERT(*this);
+			ASSERT(m_outer_current != m_outer_end);
+			ASSERT(m_inner_current);
+			m_inner_current++;
+			find_valid_or_end();
+			return *this;
+		}
+		IteratorDoubleGeneral operator++(int)
+		{
+			auto temp = *this;
+			++(*this);
+			return temp;
+		}
+
+		bool operator==(const IteratorDoubleGeneral& other) const
+		{
+			if (!*this || !other)
+				return false;
+			if (m_outer_end != other.m_outer_end)
+				return false;
+			if (m_outer_current != other.m_outer_current)
+				return false;
+			if (m_outer_current == m_outer_end)
+				return true;
+			return m_inner_current == other.m_inner_current;
+		}
+		bool operator!=(const IteratorDoubleGeneral& other) const
+		{
+			return !(*this == other);
+		}
+
+		operator bool() const
+		{
+			return m_outer_end && m_outer_current;
+		}
+
+	private:
+		IteratorDoubleGeneral(const OuterIterator& outer_end, const OuterIterator& outer_current)
+			: m_outer_end(outer_end)
+			, m_outer_current(outer_current)
+		{
+			if (outer_current != outer_end)
+			{
+				m_inner_current = m_outer_current->begin();
+				find_valid_or_end();
+			}
+		}
+
+		void find_valid_or_end()
+		{
+			while (m_inner_current == m_outer_current->end())
+			{
+				m_outer_current++;
+				if (m_outer_current == m_outer_end)
+					break;
+				m_inner_current = m_outer_current->begin();
+			}
+		}
+
+	private:
+		OuterIterator m_outer_end;
+		OuterIterator m_outer_current;
+		InnerIterator m_inner_current;
+
+		friend class IteratorDoubleGeneral<T, OuterContainer, InnerContainer, Container, !CONST>;
+		friend Container;
+	};
+
+	template<typename T, typename Container>
+	using IteratorSimple = IteratorSimpleGeneral<T, Container, false>;
+
+	template<typename T, typename Container>
+	using ConstIteratorSimple = IteratorSimpleGeneral<T, Container, true>;
+
+	template<typename T, template<typename> typename OuterContainer, template<typename> typename InnerContainer, typename Container>
+	using IteratorDouble = IteratorDoubleGeneral<T, OuterContainer, InnerContainer, Container, false>;
+
+	template<typename T, template<typename> typename OuterContainer, template<typename> typename InnerContainer, typename Container>
+	using ConstIteratorDouble = IteratorDoubleGeneral<T, OuterContainer, InnerContainer, Container, true>;
+
+}

BAN/include/BAN/LinkedList.h

@@ -1,15 +1,15 @@
 #pragma once
 
 #include <BAN/Errors.h>
-#include <BAN/Memory.h>
 #include <BAN/Move.h>
+#include <BAN/New.h>
 
 namespace BAN
 {
 
 	template<typename T, bool CONST>
 	class LinkedListIterator;
-	
+
 	template<typename T>
 	class LinkedList
 	{
@@ -38,7 +38,7 @@ namespace BAN
 		ErrorOr<void> emplace(iterator, Args&&...);
 
 		void pop_back();
-		void remove(iterator);
+		iterator remove(iterator);
 		void clear();
 
 		iterator begin()				{ return iterator(m_data, empty()); }
@@ -114,8 +114,6 @@ namespace BAN
 		friend class LinkedListIterator<T, !CONST>;
 	};
 
-
-
 	template<typename T>
 	LinkedList<T>& LinkedList<T>::operator=(const LinkedList<T>& other)
 	{
@@ -197,11 +195,11 @@ namespace BAN
 	template<typename T>
 	void LinkedList<T>::pop_back()
 	{
-		return remove(m_last);
+		remove(iterator(m_last, false));
 	}
 
 	template<typename T>
-	void LinkedList<T>::remove(iterator iter)
+	LinkedList<T>::iterator LinkedList<T>::remove(iterator iter)
 	{
 		ASSERT(!empty() && iter);
 		Node* node = iter.m_current;
@@ -212,6 +210,7 @@ namespace BAN
 		(prev ? prev->next : m_data) = next;
 		(next ? next->prev : m_last) = prev;
 		m_size--;
+		return next ? iterator(next, false) : iterator(m_last, true);
 	}
 
 	template<typename T>
@@ -292,8 +291,6 @@ namespace BAN
 		return node;
 	}
 
-
-
 	template<typename T, bool CONST>
 	template<bool C>
 	LinkedListIterator<T, CONST>::LinkedListIterator(const LinkedListIterator<T, C>& other, enable_if_t<C == CONST || !C>*)
@@ -378,7 +375,7 @@ namespace BAN
 		ASSERT(m_current);
 		return &m_current->value;
 	}
-	
+
 	template<typename T, bool CONST>
 	bool LinkedListIterator<T, CONST>::operator==(const LinkedListIterator<T, CONST>& other) const
 	{

BAN/include/BAN/Math.h

@@ -52,20 +52,53 @@ namespace BAN::Math
 	}
 
 	template<integral T>
-	inline constexpr T little_endian_to_host(const uint8_t* bytes)
+	inline constexpr bool is_power_of_two(T value)
 	{
-		T result = 0;
-		for (size_t i = 0; i < sizeof(T); i++)
-			result |= (T)bytes[i] << (i * 8);
+		if (value == 0)
+			return false;
+		return (value & (value - 1)) == 0;
+	}
+
+	template<floating_point T>
+	inline constexpr T log2(T value)
+	{
+		T result;
+		asm volatile("fyl2x" : "=t"(result) : "0"(value), "u"((T)1.0) : "st(1)");
 		return result;
 	}
 
-	template<integral T>
-	inline constexpr T big_endian_to_host(const uint8_t* bytes)
+	template<floating_point T>
+	inline constexpr T log10(T value)
 	{
-		T result = 0;
-		for (size_t i = 0; i < sizeof(T); i++)
-			result |= (T)bytes[i] << (8 * (sizeof(T) - i - 1));
+		constexpr T INV_LOG_2_10 = 0.3010299956639811952137388947244930267681898814621085413104274611;
+		T result;
+		asm volatile("fyl2x" : "=t"(result) : "0"(value), "u"(INV_LOG_2_10) : "st(1)");
+		return result;
+	}
+
+	template<floating_point T>
+	inline constexpr T log(T value, T base)
+	{
+		return log2(value) / log2(base);
+	}
+
+	template<floating_point T>
+	inline constexpr T pow(T base, T exp)
+	{
+		T result;
+		asm volatile(
+			"fyl2x;"
+			"fld1;"
+			"fld %%st(1);"
+			"fprem;"
+			"f2xm1;"
+			"faddp;"
+			"fscale;"
+			"fxch %%st(1);"
+			"fstp %%st;"
+			: "=t"(result)
+			: "0"(base), "u"(exp)
+		);
 		return result;
 	}
 

BAN/include/BAN/Move.h

@@ -2,6 +2,8 @@
 
 #include <BAN/Traits.h>
 
+#include <stddef.h>
+
 namespace BAN
 {
 
@@ -24,4 +26,7 @@ namespace BAN
 		return static_cast<T&&>(arg);
 	}
 
-}
+}
+
+inline void* operator new(size_t, void* addr)	{ return addr; }
+inline void* operator new[](size_t, void* addr)	{ return addr; }

BAN/include/BAN/New.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#if defined(__is_kernel)
+	#include <kernel/Memory/kmalloc.h>
+#else
+	#include <stdlib.h>
+#endif
+
+namespace BAN
+{
+	#if defined(__is_kernel)
+		static constexpr void*(&allocator)(size_t) = kmalloc;
+		static constexpr void(&deallocator)(void*) = kfree;
+	#else
+		static constexpr void*(&allocator)(size_t) = malloc;
+		static constexpr void(&deallocator)(void*) = free;
+	#endif
+}

BAN/include/BAN/Optional.h

@@ -0,0 +1,179 @@
+#pragma once
+
+#include <BAN/Assert.h>
+#include <BAN/Move.h>
+
+#include <stdint.h>
+
+namespace BAN
+{
+
+	template<typename T>
+	class Optional
+	{
+	public:
+		Optional();
+		Optional(const T&);
+		Optional(T&&);
+		template<typename... Args>
+		Optional(Args&&...);
+
+		~Optional();
+
+		Optional& operator=(const Optional&);
+		Optional& operator=(Optional&&);
+
+		template<typename... Args>
+		Optional& emplace(Args&&...);
+
+		T* operator->();
+		const T* operator->() const;
+
+		T& operator*();
+		const T& operator*() const;
+
+		bool has_value() const;
+
+		T&& release_value();
+		const T& value() const;
+		T& value();
+
+		void clear();
+
+	private:
+		alignas(T) uint8_t m_storage[sizeof(T)];
+		bool m_has_value { false };
+	};
+
+	template<typename T>
+	Optional<T>::Optional()
+		: m_has_value(false)
+	{}
+
+	template<typename T>
+	Optional<T>::Optional(const T& value)
+		: m_has_value(true)
+	{
+		new (m_storage) T(value);	
+	}
+
+	template<typename T>
+	Optional<T>::Optional(T&& value)
+		: m_has_value(true)
+	{
+		new (m_storage) T(BAN::move(value));
+	}
+
+	template<typename T>
+	template<typename... Args>
+	Optional<T>::Optional(Args&&... args)
+		: m_has_value(true)
+	{
+		new (m_storage) T(BAN::forward<Args>(args)...);
+	}
+
+	template<typename T>
+	Optional<T>::~Optional()
+	{
+		clear();
+	}
+
+	template<typename T>
+	Optional<T>& Optional<T>::operator=(const Optional& other)
+	{
+		clear();
+		if (other.has_value())
+		{
+			m_has_value = true;
+			new (m_storage) T(other.value());
+		}
+		return *this;
+	}
+
+	template<typename T>
+	Optional<T>& Optional<T>::operator=(Optional&& other)
+	{
+		clear();
+		if (other.has_value())
+		{
+			m_has_value = true;
+			new (m_storage) T(BAN::move(other.release_value()));
+		}
+		return *this;
+	}
+
+	template<typename T>
+	template<typename... Args>
+	Optional<T>& Optional<T>::emplace(Args&&... args)
+	{
+		clear();
+		m_has_value = true;
+		new (m_storage) T(BAN::forward<Args>(args)...);
+		return *this;
+	}
+
+	template<typename T>
+	T* Optional<T>::operator->()
+	{
+		ASSERT(has_value());
+		return &value();
+	}
+
+	template<typename T>
+	const T* Optional<T>::operator->() const
+	{
+		ASSERT(has_value());
+		return &value();
+	}
+
+	template<typename T>
+	T& Optional<T>::operator*()
+	{
+		ASSERT(has_value());
+		return value();
+	}
+
+	template<typename T>
+	const T& Optional<T>::operator*() const
+	{
+		ASSERT(has_value());
+		return value();
+	}
+
+	template<typename T>
+	bool Optional<T>::has_value() const
+	{
+		return m_has_value;
+	}
+
+	template<typename T>
+	T&& Optional<T>::release_value()
+	{
+		ASSERT(has_value());
+		m_has_value = false;
+		return BAN::move((T&)m_storage);
+	}
+
+	template<typename T>
+	const T& Optional<T>::value() const
+	{
+		ASSERT(has_value());
+		return (const T&)m_storage;
+	}
+
+	template<typename T>
+	T& Optional<T>::value()
+	{
+		ASSERT(has_value());
+		return (T&)m_storage;
+	}
+
+	template<typename T>
+	void Optional<T>::clear()
+	{
+		if (m_has_value)
+			value().~T();
+		m_has_value = false;
+	}
+
+}

BAN/include/BAN/Queue.h

@@ -1,9 +1,10 @@
 #pragma once
 
 #include <BAN/Errors.h>
+#include <BAN/Iterators.h>
 #include <BAN/Math.h>
-#include <BAN/Memory.h>
 #include <BAN/Move.h>
+#include <BAN/New.h>
 
 namespace BAN
 {
@@ -14,6 +15,8 @@ namespace BAN
 	public:
 		using size_type = size_t;
 		using value_type = T;
+		using iterator = IteratorSimple<T, Queue>;
+		using const_iterator = ConstIteratorSimple<T, Queue>;
 
 	public:
 		Queue() = default;
@@ -32,6 +35,11 @@ namespace BAN
 		ErrorOr<void> reserve(size_type);
 		ErrorOr<void> shrink_to_fit();
 
+		iterator begin() { return iterator(m_data); }
+		iterator end() { return iterator(m_data + m_size); }
+		const_iterator begin() const { return const_iterator(m_data); }
+		const_iterator end() const { return const_iterator(m_data + m_size); }
+
 		void pop();
 		void clear();
 

BAN/include/BAN/RefPtr.h

@@ -1,27 +1,12 @@
 #pragma once
 
-
 #include <BAN/Errors.h>
 #include <BAN/Move.h>
 #include <BAN/NoCopyMove.h>
-
-#if defined(__is_kernel)
-	#include <kernel/kmalloc.h>
-#else
-	#include <stdlib.h>
-#endif
-
 #include <stdint.h>
 
 namespace BAN
 {
-	#if defined(__is_kernel)
-		static constexpr void*(&allocator)(size_t) = kmalloc;
-		static constexpr void(&deallocator)(void*) = kfree;
-	#else
-		static constexpr void*(&allocator)(size_t) = malloc;
-		static constexpr void(&deallocator)(void*) = free;
-	#endif
 
 	template<typename T>
 	class RefCounted
@@ -68,7 +53,6 @@ namespace BAN
 			if (m_pointer)
 				m_pointer->ref();
 		}
-
 		~RefPtr() { clear(); }
 
 		template<typename U>
@@ -90,6 +74,10 @@ namespace BAN
 
 		RefPtr(const RefPtr& other) { *this = other; }
 		RefPtr(RefPtr&& other) { *this = move(other); }
+		template<typename U>
+		RefPtr(const RefPtr<U>& other) { *this = other; }
+		template<typename U>
+		RefPtr(RefPtr<U>&& other) { *this = move(other); }
 
 		RefPtr& operator=(const RefPtr& other)
 		{
@@ -108,6 +96,25 @@ namespace BAN
 			return *this;
 		}
 
+		template<typename U>
+		RefPtr& operator=(const RefPtr<U>& other)
+		{
+			clear();
+			m_pointer = other.m_pointer;
+			if (m_pointer)
+				m_pointer->ref();
+			return *this;
+		}
+
+		template<typename U>
+		RefPtr& operator=(RefPtr<U>&& other)
+		{
+			clear();
+			m_pointer = other.m_pointer;
+			other.m_pointer = nullptr;
+			return *this;
+		}
+
 		T* ptr() { ASSERT(!empty()); return m_pointer; }
 		const T* ptr() const { ASSERT(!empty()); return m_pointer; }
 
@@ -129,9 +136,9 @@ namespace BAN
 
 	private:
 		T* m_pointer = nullptr;
+
+		template<typename U>
+		friend class RefPtr;
 	};
 
 }
-
-inline void* operator new(size_t, void* addr)	{ return addr; }
-inline void* operator new[](size_t, void* addr)	{ return addr; }

BAN/include/BAN/ScopeGuard.h

@@ -13,10 +13,16 @@ namespace BAN
 		{ }
 		~ScopeGuard()
 		{
-			m_func();
+			if (m_enabled)
+				m_func();
+		}
+		void disable()
+		{
+			m_enabled = false;
 		}
 	private:
 		BAN::Function<void()> m_func;
+		bool m_enabled { true };
 	};
 
 }

BAN/include/BAN/Span.h

@@ -0,0 +1,132 @@
+#pragma once
+
+#include <BAN/Assert.h>
+#include <BAN/Iterators.h>
+
+#include <stddef.h>
+
+namespace BAN
+{
+
+	template<typename T>
+	class Span
+	{
+	public:
+		using value_type = T;
+		using size_type = size_t;
+		using iterator = IteratorSimple<T, Span>;
+		using const_iterator = ConstIteratorSimple<T, Span>;
+
+	public:
+		Span() = default;
+		Span(T*, size_type);
+		Span(Span<T>&);
+		template<typename S>
+		requires(is_same_v<T, const S>)
+		Span(const Span<S>&);
+
+		iterator begin() { return iterator(m_data); }
+		iterator end() { return iterator(m_data + m_size); }
+		const_iterator begin() const { return const_iterator(m_data); }
+		const_iterator end() const { return const_iterator(m_data + m_size); }
+
+		T& operator[](size_type);
+		const T& operator[](size_type) const;
+
+		T* data();
+		const T* data() const;
+
+		bool empty() const;
+		size_type size() const;
+
+		void clear();
+
+		Span slice(size_type, size_type = ~size_type(0));
+
+	private:
+		T* m_data = nullptr;
+		size_type m_size = 0;
+	};
+
+	template<typename T>
+	Span<T>::Span(T* data, size_type size)
+		: m_data(data)
+		, m_size(size)
+	{
+	}
+
+	template<typename T>
+	Span<T>::Span(Span& other)
+		: m_data(other.data())
+		, m_size(other.size())
+	{
+	}
+
+	template<typename T>
+	template<typename S>
+	requires(is_same_v<T, const S>)
+	Span<T>::Span(const Span<S>& other)
+		: m_data(other.data())
+		, m_size(other.size())
+	{
+	}
+
+	template<typename T>
+	T& Span<T>::operator[](size_type index)
+	{
+		ASSERT(m_data);
+		ASSERT(index < m_size);
+		return m_data[index];
+	}
+
+	template<typename T>
+	const T& Span<T>::operator[](size_type index) const
+	{
+		ASSERT(m_data);
+		ASSERT(index < m_size);
+		return m_data[index];
+	}
+
+	template<typename T>
+	T* Span<T>::data()
+	{
+		return m_data;
+	}
+
+	template<typename T>
+	const T* Span<T>::data() const
+	{
+		return m_data;
+	}
+
+	template<typename T>
+	bool Span<T>::empty() const
+	{
+		return m_size == 0;
+	}
+
+	template<typename T>
+	typename Span<T>::size_type Span<T>::size() const
+	{
+		return m_size;
+	}
+
+	template<typename T>
+	void Span<T>::clear()
+	{
+		m_data = nullptr;
+		m_size = 0;
+	}
+
+	template<typename T>
+	Span<T> Span<T>::slice(size_type start, size_type length)
+	{
+		ASSERT(m_data);
+		ASSERT(start <= m_size);
+		if (length == ~size_type(0))
+			length = m_size - start;
+		ASSERT(start + length <= m_size);
+		return Span(m_data + start, m_size - start - length);
+	}
+
+}

BAN/include/BAN/String.h

@@ -1,8 +1,10 @@
 #pragma once
 
+#include <BAN/Errors.h>
 #include <BAN/ForwardList.h>
 #include <BAN/Formatter.h>
 #include <BAN/Hash.h>
+#include <BAN/Iterators.h>
 
 namespace BAN
 {
@@ -11,6 +13,8 @@ namespace BAN
 	{
 	public:
 		using size_type = size_t;
+		using iterator = IteratorSimple<char, String>;
+		using const_iterator = ConstIteratorSimple<char, String>;
 
 	public:
 		String();
@@ -38,6 +42,17 @@ namespace BAN
 
 		void clear();
 
+		const_iterator begin() const { return const_iterator(m_data); }
+		iterator begin() { return iterator(m_data); }
+		const_iterator end() const { return const_iterator(m_data + m_size); }
+		iterator end() { return iterator(m_data + m_size); }
+
+		char front() const	{ ASSERT(!empty()); return m_data[0]; }
+		char& front()		{ ASSERT(!empty()); return m_data[0]; }
+
+		char back() const	{ ASSERT(!empty()); return m_data[m_size - 1]; }
+		char& back()		{ ASSERT(!empty()); return m_data[m_size - 1]; }
+
 		char operator[](size_type) const;
 		char& operator[](size_type);
 
@@ -73,7 +88,7 @@ namespace BAN
 	String String::formatted(const char* format, const Args&... args)
 	{
 		String result;
-		BAN::Formatter::print([&](char c){ result.push_back(c); }, format, args...);
+		BAN::Formatter::print([&](char c){ MUST(result.push_back(c)); }, format, args...);
 		return result;
 	}
 

BAN/include/BAN/StringView.h

@@ -2,6 +2,7 @@
 
 #include <BAN/ForwardList.h>
 #include <BAN/Formatter.h>
+#include <BAN/Iterators.h>
 
 namespace BAN
 {
@@ -10,12 +11,16 @@ namespace BAN
 	{
 	public:
 		using size_type = size_t;
+		using const_iterator = ConstIteratorSimple<char, StringView>;
 
 	public:
 		StringView();
 		StringView(const String&);
 		StringView(const char*, size_type = -1);
 
+		const_iterator begin() const { return const_iterator(m_data); }
+		const_iterator end() const { return const_iterator(m_data + m_size); }
+
 		char operator[](size_type) const;
 
 		bool operator==(const String&) const;
@@ -30,6 +35,7 @@ namespace BAN
 		char back() const;
 		char front() const;
 
+		bool contains(char) const;
 		size_type count(char) const;
 
 		bool empty() const;

BAN/include/BAN/Time.h

@@ -9,15 +9,18 @@ namespace BAN
 
 	struct Time
 	{
-		uint8_t	second;
-		uint8_t	minute;
-		uint8_t	hour;
-		uint8_t week_day;
-		uint8_t	day;
+		uint32_t year;
 		uint8_t	month;
-		int		year;
+		uint8_t	day;
+		uint8_t	hour;
+		uint8_t	minute;
+		uint8_t	second;
+		uint8_t week_day;
 	};
 
+	uint64_t to_unix_time(const BAN::Time&);
+	BAN::Time from_unix_time(uint64_t);
+
 }
 
 namespace BAN::Formatter

BAN/include/BAN/Traits.h

@@ -2,7 +2,7 @@
 
 namespace BAN
 {
-	
+
 	template<typename T> struct remove_refenrece { using type = T; };
 	template<typename T> struct remove_refenrece<T&> { using type =  T; };
 	template<typename T> struct remove_refenrece<T&&> { using type = T; };
@@ -30,6 +30,10 @@ namespace BAN
 	template<typename T> struct maybe_const<true, T> { using type = const T; };
 	template<bool B, typename T> using maybe_const_t = typename maybe_const<B, T>::type;
 
+	template<bool B, typename T1, typename T2> struct either_or { using type = T2; };
+	template<typename T1, typename T2> struct either_or<true, T1, T2> { using type = T1; };
+	template<bool B, typename T1, typename T2> using either_or_t = typename either_or<B, T1, T2>::type;
+
 	struct true_type { static constexpr bool value = true; };
 	struct false_type { static constexpr bool value = false; };
 
@@ -40,6 +44,7 @@ namespace BAN
 	template<typename T> struct is_lvalue_reference		: false_type {};
 	template<typename T> struct is_lvalue_reference<T&>	: true_type {};
 	template<typename T> inline constexpr bool is_lvalue_reference_v = is_lvalue_reference<T>::value;
+	template<typename T> concept lvalue_reference = is_lvalue_reference_v<T>;
 
 	template<typename T> struct is_integral { static constexpr bool value = requires (T t, T* p, void (*f)(T)) { reinterpret_cast<T>(t); f(0); p + t; }; };
 	template<typename T> inline constexpr bool is_integral_v = is_integral<T>::value;
@@ -60,6 +65,21 @@ namespace BAN
 	template<typename T> inline constexpr bool is_pointer_v = is_pointer<T>::value;
 	template<typename T> concept pointer = is_pointer_v<T>;
 
+	template<typename T> struct is_const			: false_type {};
+	template<typename T> struct is_const<const T>	: true_type {};
+	template<typename T> inline constexpr bool is_const_v = is_const<T>::value;
+
+	template<typename T> struct is_arithmetic { static constexpr bool value = is_integral_v<T> || is_floating_point_v<T>; };
+	template<typename T> inline constexpr bool is_arithmetic_v = is_arithmetic<T>::value;
+
+	namespace detail
+	{
+		template<typename T, bool = is_arithmetic_v<T>> struct is_signed { static constexpr bool value = T(-1) < T(0); };
+		template<typename T> struct is_signed<T, false> : false_type {};
+	}
+	template<typename T> struct is_signed : detail::is_signed<T> {};
+	template<typename T> inline constexpr bool is_signed_v = is_signed<T>::value;
+
 	template<typename T> struct less	{ constexpr bool operator()(const T& lhs, const T& rhs) const { return lhs < rhs; } };
 	template<typename T> struct equal	{ constexpr bool operator()(const T& lhs, const T& rhs) const { return lhs == rhs; } };
 	template<typename T> struct greater	{ constexpr bool operator()(const T& lhs, const T& rhs) const { return lhs > rhs; } };

BAN/include/BAN/UTF8.h

@@ -3,26 +3,79 @@
 #include <stddef.h>
 #include <stdint.h>
 
-namespace BAN
+namespace BAN::UTF8
 {
 
-	static constexpr uint16_t utf8_to_codepoint(uint8_t* bytes, size_t count)
+	static constexpr uint32_t invalid = 0xFFFFFFFF;
+
+	constexpr uint32_t byte_length(uint8_t first_byte)
 	{
-		if (count > 3)
-			return 0xFFFF;
+		if ((first_byte & 0x80) == 0x00)
+			return 1;
+		if ((first_byte & 0xE0) == 0xC0)
+			return 2;
+		if ((first_byte & 0xF0) == 0xE0)
+			return 3;
+		if ((first_byte & 0xF8) == 0xF0)
+			return 4;
+		return 0;
+	}
 
-		for (size_t i = 1; i < count; i++)
+	constexpr uint32_t to_codepoint(uint8_t* bytes)
+	{
+		uint32_t length = byte_length(bytes[0]);
+
+		for (uint32_t i = 1; i < length; i++)
 			if ((bytes[i] & 0xC0) != 0x80)
-				return 0xFFFF;
-
-		switch (count)
+				return UTF8::invalid;
+		
+		switch (length)
 		{
-			case 1: return   bytes[0];
-			case 2: return ((bytes[0] & 0x1F) <<  6) |  (bytes[1] & 0x3F);
-			case 3: return ((bytes[0] & 0x1F) << 12) | ((bytes[1] & 0x3F) << 6) | (bytes[2] & 0x3F);
+			case 1: return ((bytes[0] & 0x80) != 0x00) ? UTF8::invalid :   bytes[0];
+			case 2: return ((bytes[0] & 0xE0) != 0xC0) ? UTF8::invalid : ((bytes[0] & 0x1F) <<  6) |  (bytes[1] & 0x3F);
+			case 3: return ((bytes[0] & 0xF0) != 0xE0) ? UTF8::invalid : ((bytes[0] & 0x0F) << 12) | ((bytes[1] & 0x3F) <<  6) |  (bytes[2] & 0x3F);
+			case 4: return ((bytes[0] & 0xF8) != 0xF0) ? UTF8::invalid : ((bytes[0] & 0x07) << 18) | ((bytes[1] & 0x3F) << 12) | ((bytes[2] & 0x3F) << 6) | (bytes[3] & 0x3F);
 		}
 
-		return 0xFFFF;
+		return UTF8::invalid;
+	}
+
+	template<typename T>
+	constexpr bool from_codepoints(const T* codepoints, size_t count, char* out)
+	{
+		uint8_t* ptr = (uint8_t*)out;
+
+		for (size_t i = 0; i < count; i++)
+		{
+			if (codepoints[i] < 0x80)
+			{
+				*ptr++ = codepoints[i];
+			}
+			else if (codepoints[i] < 0x800)
+			{
+				*ptr++ = 0xC0 | ((codepoints[i] >> 6) & 0x1F);
+				*ptr++ = 0x80 | ((codepoints[i] >> 0) & 0x3F);
+			}
+			else if (codepoints[i] < 0x10000)
+			{
+				*ptr++ = 0xE0 | ((codepoints[i] >> 12) & 0x0F);
+				*ptr++ = 0x80 | ((codepoints[i] >>  6) & 0x3F);
+				*ptr++ = 0x80 | ((codepoints[i] >>  0) & 0x3F);
+			}
+			else if (codepoints[i] < 0x110000)
+			{
+				*ptr++ = 0xF0 | ((codepoints[i] >> 18) & 0x07);
+				*ptr++ = 0x80 | ((codepoints[i] >> 12) & 0x3F);
+				*ptr++ = 0x80 | ((codepoints[i] >>  6) & 0x3F);
+				*ptr++ = 0x80 | ((codepoints[i] >>  0) & 0x3F);
+			}
+			else
+			{
+				return false;
+			}
+		}
+
+		return true;
 	}
 
 }

BAN/include/BAN/UniqPtr.h

@@ -0,0 +1,98 @@
+#pragma once
+
+#include <BAN/Errors.h>
+#include <BAN/NoCopyMove.h>
+
+namespace BAN
+{
+
+	template<typename T>
+	class UniqPtr
+	{
+		BAN_NON_COPYABLE(UniqPtr);
+
+	public:
+		UniqPtr() = default;
+
+		template<typename U>
+		UniqPtr(UniqPtr<U>&& other)
+		{
+			m_pointer = other.m_pointer;
+			other.m_pointer = nullptr;
+		}
+
+		~UniqPtr()
+		{
+			clear();
+		}
+
+		static UniqPtr adopt(T* pointer)
+		{
+			UniqPtr uniq;
+			uniq.m_pointer = pointer;
+			return uniq;
+		}
+
+		template<typename... Args>
+		static BAN::ErrorOr<UniqPtr> create(Args&&... args)
+		{
+			UniqPtr uniq;
+			uniq.m_pointer = new T(BAN::forward<Args>(args)...);
+			if (uniq.m_pointer == nullptr)
+				return BAN::Error::from_errno(ENOMEM);
+			return uniq;
+		}
+
+		template<typename U>
+		UniqPtr& operator=(UniqPtr<U>&& other)
+		{
+			clear();
+			m_pointer = other.m_pointer;
+			other.m_pointer = nullptr;
+			return *this;
+		}
+
+		T& operator*()
+		{
+			ASSERT(m_pointer);
+			return *m_pointer;
+		}
+
+		const T& operator*() const
+		{
+			ASSERT(m_pointer);
+			return *m_pointer;
+		}
+
+		T* operator->()
+		{
+			ASSERT(m_pointer);
+			return m_pointer;	
+		}
+
+		const T* operator->() const
+		{
+			ASSERT(m_pointer);
+			return m_pointer;
+		}
+
+		T* ptr() { return m_pointer; }
+		const T* ptr() const { return m_pointer; }
+
+		void clear()
+		{
+			if (m_pointer)
+				delete m_pointer;
+			m_pointer = nullptr;
+		}
+
+		operator bool() const { return m_pointer != nullptr; }
+
+	private:
+		T* m_pointer = nullptr;
+
+		template<typename U>
+		friend class UniqPtr;
+	};
+
+}

BAN/include/BAN/Variant.h

@@ -4,144 +4,290 @@
 #include <BAN/Math.h>
 #include <BAN/Move.h>
 
+#include <string.h>
+
 namespace BAN
 {
 
-	template<typename T1, typename T2>
+	namespace detail
+	{
+
+		template<typename T>
+		constexpr size_t size_ref_as_ptr() { return is_lvalue_reference_v<T> ? sizeof(remove_reference_t<T>*) : sizeof(T); }
+		template<typename T>
+		constexpr size_t align_ref_as_ptr() { return is_lvalue_reference_v<T> ? alignof(remove_reference_t<T>*) : alignof(T); }
+
+		template<typename T>
+		constexpr size_t max_size_ref_as_ptr() { return size_ref_as_ptr<T>(); }
+		template<typename T0, typename T1, typename... Ts>
+		constexpr size_t max_size_ref_as_ptr() { return size_ref_as_ptr<T0>() > size_ref_as_ptr<T1>() ? max_size_ref_as_ptr<T0, Ts...>() : max_size_ref_as_ptr<T1, Ts...>(); }
+
+		template<typename T>
+		constexpr size_t max_align_ref_as_ptr() { return align_ref_as_ptr<T>(); }
+		template<typename T0, typename T1, typename... Ts>
+		constexpr size_t max_align_ref_as_ptr() { return align_ref_as_ptr<T0>() > align_ref_as_ptr<T1>() ? max_align_ref_as_ptr<T0, Ts...>() : max_align_ref_as_ptr<T1, Ts...>(); }
+
+		template<typename T, typename T0, typename... Ts>
+		constexpr size_t index()
+		{
+			if constexpr(is_same_v<T, T0>)
+				return 0;
+			else if constexpr(sizeof...(Ts) == 0)
+				return 1;
+			else
+				return index<T, Ts...>() + 1;
+		}
+
+		template<typename T, typename... Ts>
+		void destruct(size_t index, uint8_t* data)
+		{
+			if (index == 0)
+				if constexpr(!is_lvalue_reference_v<T>)
+					reinterpret_cast<T*>(data)->~T();
+				else;
+			else if constexpr(sizeof...(Ts) > 0)
+				destruct<Ts...>(index - 1, data);
+			else
+				ASSERT_NOT_REACHED();
+		}
+
+		template<typename T, typename... Ts>
+		void move_construct(size_t index, uint8_t* source, uint8_t* target)
+		{
+			if (index == 0)
+				if constexpr(!is_lvalue_reference_v<T>)
+					new (target) T(move(*reinterpret_cast<T*>(source)));
+				else
+					memcpy(target, source, sizeof(remove_reference_t<T>*));
+			else if constexpr(sizeof...(Ts) > 0)
+				move_construct<Ts...>(index - 1, source, target);
+			else
+				ASSERT_NOT_REACHED();
+		}
+
+		template<typename T, typename... Ts>
+		void copy_construct(size_t index, const uint8_t* source, uint8_t* target)
+		{
+			if (index == 0)
+				if constexpr(!is_lvalue_reference_v<T>)
+					new (target) T(*reinterpret_cast<const T*>(source));
+				else
+					memcpy(target, source, sizeof(remove_reference_t<T>*));
+			else if constexpr(sizeof...(Ts) > 0)
+				copy_construct<Ts...>(index - 1, source, target);
+			else
+				ASSERT_NOT_REACHED();
+		}
+
+		template<typename T, typename... Ts>
+		void move_assign(size_t index, uint8_t* source, uint8_t* target)
+		{
+			if (index == 0)
+				if constexpr(!is_lvalue_reference_v<T>)
+					*reinterpret_cast<T*>(target) = move(*reinterpret_cast<T*>(source));
+				else
+					memcpy(target, source, sizeof(remove_reference_t<T>*));
+			else if constexpr(sizeof...(Ts) > 0)
+				move_assign<Ts...>(index - 1, source, target);
+			else
+				ASSERT_NOT_REACHED();
+		}
+
+		template<typename T, typename... Ts>
+		void copy_assign(size_t index, const uint8_t* source, uint8_t* target)
+		{
+			if (index == 0)
+				if constexpr(!is_lvalue_reference_v<T>)
+					*reinterpret_cast<T*>(target) = *reinterpret_cast<const T*>(source);
+				else
+					memcpy(target, source, sizeof(remove_reference_t<T>*));
+			else if constexpr(sizeof...(Ts) > 0)
+				copy_assign<Ts...>(index - 1, source, target);
+			else
+				ASSERT_NOT_REACHED();
+		}
+
+	}
+
+	template<typename... Ts>
+		requires (!is_const_v<Ts> && ...)
 	class Variant
 	{
-	public:
-		static_assert(!is_same_v<T1, T2>);
+	private:
+		template<typename T>
+		static constexpr bool can_have() { return detail::index<T, Ts...>() != invalid_index(); }
+		static constexpr size_t invalid_index() { return sizeof...(Ts); }
 
+	public:
 		Variant() = default;
 
-		Variant(const T1& value)	{ set(value); }
-		Variant(T1&& value)			{ set(move(value)); }
-		Variant(const T2& value)	{ set(value); }
-		Variant(T2&& value)			{ set(move(value)); }
+		Variant(Variant&& other)
+			: m_index(other.m_index)
+		{
+			detail::move_construct<Ts...>(other.m_index, other.m_storage, m_storage);
+			other.clear();
+		}
 
-		Variant(const Variant<T1, T2>& other)	{ *this = other; }
-		Variant(Variant<T1, T2>&& other)		{ *this = move(other); }
+		Variant(const Variant& other)
+			: m_index(other.m_index)
+		{
+			detail::copy_construct<Ts...>(other.m_index, other.m_storage, m_storage);
+		}
 
-		~Variant() { clear(); }
+		template<typename T>
+		Variant(T&& value) requires (can_have<T>() && !is_lvalue_reference_v<T>)
+			: m_index(detail::index<T, Ts...>())
+		{
+			new (m_storage) T(move(value));	
+		}
 
-		Variant<T1, T2>& operator=(const Variant<T1, T2>& other);
-		Variant<T1, T2>& operator=(Variant<T1, T2>&& other);
+		template<typename T>
+		Variant(const T& value) requires (can_have<T>() && !is_lvalue_reference_v<T>)
+			: m_index(detail::index<T, Ts...>())
+		{
+			new (m_storage) T(value);	
+		}
 
-		template<typename U>
-		bool is() const;
+		~Variant()
+		{
+			clear();
+		}
 
-		template<typename U>
-		void set(U&&);
-		template<typename U>
-		void set(const U& value) { set(move(U(value))); } 
+		Variant& operator=(Variant&& other)
+		{
+			if (m_index == other.m_index)
+				detail::move_assign<Ts...>(m_index, other.m_storage, m_storage);
+			else
+			{
+				clear();
+				detail::move_construct<Ts...>(other.m_index, other.m_storage, m_storage);
+				m_index = other.m_index;
+			}
+			other.clear();
+			return *this;
+		}
 
-		template<typename U>
-		const U& get() const;
-		template<typename U>
-		U& get();
+		Variant& operator=(const Variant& other)
+		{
+			if (m_index == other.m_index)
+				detail::copy_assign<Ts...>(m_index, other.m_storage, m_storage);
+			else
+			{
+				clear();
+				detail::copy_construct<Ts...>(other.m_index, other.m_storage, m_storage);
+				m_index = other.m_index;
+			}
+			return *this;
+		}
 
-		void clear();
+		template<typename T>
+		Variant& operator=(T&& value) requires (can_have<T>() && !is_lvalue_reference_v<T>)
+		{
+			if (size_t index = detail::index<T, Ts...>(); index == m_index)
+				get<T>() = move(value);
+			else
+			{
+				clear();
+				new (m_storage) T(move(value));
+				m_index = index;
+			}
+			return *this;
+		}
+
+		template<typename T>
+		Variant& operator=(const T& value) requires (can_have<T>() && !is_lvalue_reference_v<T>)
+		{
+			if (size_t index = detail::index<T, Ts...>(); index == m_index)
+				get<T>() = value;
+			else
+			{
+				clear();
+				new (m_storage) T(value);
+				m_index = index;
+			}
+			return *this;
+		}
+
+		template<typename T>
+		bool has() const requires (can_have<T>())
+		{
+			return m_index == detail::index<T, Ts...>();
+		}
+
+		template<typename T>
+		void set(T&& value) requires (can_have<T>() && !is_lvalue_reference_v<T>)
+		{
+			if (has<T>())
+				get<T>() = move(value);
+			else
+			{
+				clear();
+				m_index = detail::index<T, Ts...>();
+				new (m_storage) T(move(value));
+			}
+		}
+
+		template<typename T>
+		void set(const T& value) requires (can_have<T>() && !is_lvalue_reference_v<T>)
+		{
+			if (has<T>())
+				get<T>() = value;
+			else
+			{
+				clear();
+				m_index = detail::index<T, Ts...>();
+				new (m_storage) T(value);
+			}
+		}
+
+		template<typename T>
+		void set(T value) requires (can_have<T>() && is_lvalue_reference_v<T>)
+		{
+			clear();
+			m_index = detail::index<T, Ts...>();
+			*reinterpret_cast<remove_reference_t<T>**>(m_storage) = &value;
+		}
+
+		template<typename T>
+		T& get() requires (can_have<T>() && !is_lvalue_reference_v<T>)
+		{
+			ASSERT(has<T>());
+			return *reinterpret_cast<T*>(m_storage);
+		}
+
+		template<typename T>
+		const T& get() const requires (can_have<T>() && !is_lvalue_reference_v<T>)
+		{
+			ASSERT(has<T>());
+			return *reinterpret_cast<const T*>(m_storage);
+		}
+
+		template<typename T>
+		T get() requires (can_have<T>() && is_lvalue_reference_v<T>)
+		{
+			ASSERT(has<T>());
+			return **reinterpret_cast<remove_reference_t<T>**>(m_storage);
+		}
+
+		template<typename T>
+		const T get() const requires (can_have<T>() && is_lvalue_reference_v<T>)
+		{
+			ASSERT(has<T>());
+			return **reinterpret_cast<const remove_reference_t<T>**>(m_storage);
+		}
+
+		void clear()
+		{
+			if (m_index != invalid_index())
+			{
+				detail::destruct<Ts...>(m_index, m_storage);
+				m_index = invalid_index();
+			}
+		}
 
 	private:
-		static constexpr uint32_t m_size = Math::max(sizeof(T1), sizeof(T2));
-		uint8_t m_storage[m_size] = {};
-		uint32_t m_index = 0;
+		alignas(detail::max_align_ref_as_ptr<Ts...>()) uint8_t m_storage[detail::max_size_ref_as_ptr<Ts...>()] {};
+		size_t m_index { invalid_index() };
 	};
 
-	template<typename T1, typename T2>
-	Variant<T1, T2>& Variant<T1, T2>::operator=(const Variant<T1, T2>& other)
-	{
-		clear();
-		if (other.is<T1>())
-			set(other.get<T1>());
-		if (other.is<T2>())
-			set(other.get<T2>());
-		return *this;
-	}
-
-	template<typename T1, typename T2>
-	Variant<T1, T2>& Variant<T1, T2>::operator=(Variant<T1, T2>&& other)
-	{
-		clear();
-		if (other.is<T1>())
-			set(move(other.get<T1>()));
-		if (other.is<T2>())
-			set(move(other.get<T2>()));
-		other.clear();
-		return *this;
-	}
-
-	template<typename T1, typename T2>
-	template<typename U>
-	bool Variant<T1, T2>::is() const
-	{
-		if constexpr(is_same_v<T1, U>)
-			return m_index == 1;
-		if constexpr(is_same_v<T2, U>)
-			return m_index == 2;
-		return false;
-	}
-
-
-	template<typename T1, typename T2>
-	template<typename U>
-	void Variant<T1, T2>::set(U&& value)
-	{
-		static_assert(is_same_v<T1, U> || is_same_v<T2, U>);
-		clear();
-		if constexpr(is_same_v<T1, U>)
-		{
-			new (m_storage) T1(move(value));
-			m_index = 1;
-		}
-		if constexpr(is_same_v<T2, U>)
-		{
-			new (m_storage) T2(move(value));
-			m_index = 2;
-		}
-	}
-
-	template<typename T1, typename T2>
-	template<typename U>
-	const U& Variant<T1, T2>::get() const
-	{
-		static_assert(is_same_v<T1, U> || is_same_v<T2, U>);
-		if constexpr(is_same_v<T1, U>)
-		{
-			ASSERT(m_index == 1);
-			return *(T1*)m_storage;
-		}
-		if constexpr(is_same_v<T2, U>)
-		{
-			ASSERT(m_index == 2);
-			return *(T2*)m_storage;
-		}
-	}
-
-	template<typename T1, typename T2>
-	template<typename U>
-	U& Variant<T1, T2>::get()
-	{
-		static_assert(is_same_v<T1, U> || is_same_v<T2, U>);
-		if constexpr(is_same_v<T1, U>)
-		{
-			ASSERT(m_index == 1);
-			return *(T1*)m_storage;
-		}
-		if constexpr(is_same_v<T2, U>)
-		{
-			ASSERT(m_index == 2);
-			return *(T2*)m_storage;
-		}
-	}
-
-	template<typename T1, typename T2>
-	void Variant<T1, T2>::clear()
-	{
-		if (is<T1>()) ((T1*)m_storage)->~T1();
-		if (is<T2>()) ((T2*)m_storage)->~T2();
-		m_index = 0;
-	}
-
 }

BAN/include/BAN/Vector.h

@@ -1,16 +1,15 @@
 #pragma once
 
 #include <BAN/Errors.h>
+#include <BAN/Iterators.h>
 #include <BAN/Math.h>
-#include <BAN/Memory.h>
 #include <BAN/Move.h>
+#include <BAN/New.h>
+#include <BAN/Span.h>
 
 namespace BAN
 {
 
-	template<typename T, bool CONST>
-	class VectorIterator;
-
 	// T must be move assignable, move constructable (and copy constructable for some functions)
 	template<typename T>
 	class Vector
@@ -18,8 +17,8 @@ namespace BAN
 	public:
 		using size_type = size_t;
 		using value_type = T;
-		using iterator = VectorIterator<T, false>;
-		using const_iterator = VectorIterator<T, true>;
+		using iterator = IteratorSimple<T, Vector>;
+		using const_iterator = ConstIteratorSimple<T, Vector>;
 
 	public:
 		Vector() = default;
@@ -40,10 +39,10 @@ namespace BAN
 		ErrorOr<void> insert(size_type, T&&);
 		ErrorOr<void> insert(size_type, const T&);
 		
-		iterator begin()				{ return iterator      (m_data); }
-		const_iterator begin() const	{ return const_iterator(m_data); }
-		iterator end()					{ return iterator      (m_data + m_size); }
-		const_iterator end() const		{ return const_iterator(m_data + m_size); }
+		iterator begin() { return iterator(m_data); }
+		iterator end() { return iterator(m_data + m_size); }
+		const_iterator begin() const { return const_iterator(m_data); }
+		const_iterator end() const { return const_iterator(m_data + m_size); }
 
 		void pop_back();
 		void remove(size_type);
@@ -54,6 +53,9 @@ namespace BAN
 
 		bool contains(const T&) const;
 
+		Span<T> span() { return Span(m_data, m_size); }
+		const Span<T> span() const { return Span(m_data, m_size); }
+
 		const T& operator[](size_type) const;
 		T& operator[](size_type);
 
@@ -62,7 +64,7 @@ namespace BAN
 		const T& front() const;
 		T& front();
 
-		ErrorOr<void> resize(size_type);
+		ErrorOr<void> resize(size_type, const T& = T());
 		ErrorOr<void> reserve(size_type);
 		ErrorOr<void> shrink_to_fit();
 
@@ -76,54 +78,9 @@ namespace BAN
 	private:
 		T*			m_data		= nullptr;
 		size_type	m_capacity	= 0;
-		size_type	m_size		= 0;	
+		size_type	m_size		= 0;
 	};
 
-	template<typename T, bool CONST>
-	class VectorIterator
-	{
-	public:
-		using value_type = T;
-		using data_type = maybe_const_t<CONST, T>;
-
-	public:
-		VectorIterator() = default;
-		template<bool C>
-		VectorIterator(const VectorIterator<T, C>& other, enable_if_t<C == CONST || !C>)
-			: m_data(other.m_data)
-		{
-		}
-		
-		VectorIterator<T, CONST>& operator++()		{ m_data++; return *this; }
-		VectorIterator<T, CONST>& operator--()		{ m_data--; return *this; }
-		VectorIterator<T, CONST> operator++(int)	{ auto temp = *this; ++(*this); return temp; }
-		VectorIterator<T, CONST> operator--(int)	{ auto temp = *this; --(*this); return temp; }
-
-		template<bool ENABLE = !CONST>
-		enable_if_t<ENABLE, T&> operator*()		{ ASSERT(m_data); return *m_data; }
-		const T& operator*() const				{ ASSERT(m_data); return *m_data; }
-
-		template<bool ENABLE = !CONST>
-		enable_if_t<ENABLE, T*> operator->()	{ ASSERT(m_data); return m_data; }
-		const T* operator->() const				{ ASSERT(m_data); return m_data; }
-
-		bool operator==(const VectorIterator<T, CONST>& other) const { return m_data == other.m_data; }
-		bool operator!=(const VectorIterator<T, CONST>& other) const { return !(*this == other); }
-
-		operator bool() const { return m_data; }
-
-	private:
-		VectorIterator(data_type* data) : m_data(data) { }
-
-	private:
-		data_type* m_data = nullptr;
-
-		friend class Vector<T>;
-		friend class VectorIterator<T, !CONST>;
-	};
-
-
-
 	template<typename T>
 	Vector<T>::Vector(Vector<T>&& other)
 	{
@@ -256,7 +213,7 @@ namespace BAN
 	template<typename T>
 	ErrorOr<void> Vector<T>::insert(size_type index, const T& value)
 	{
-		return insert(move(T(value)), index);
+		return insert(index, move(T(value)));
 	}
 
 	template<typename T>
@@ -296,7 +253,7 @@ namespace BAN
 				return true;
 		return false;
 	}
-	
+
 	template<typename T>
 	const T& Vector<T>::operator[](size_type index) const
 	{
@@ -340,7 +297,7 @@ namespace BAN
 	}
 
 	template<typename T>
-	ErrorOr<void> Vector<T>::resize(size_type size)
+	ErrorOr<void> Vector<T>::resize(size_type size, const T& value)
 	{
 		TRY(ensure_capacity(size));
 		if (size < m_size)
@@ -348,7 +305,7 @@ namespace BAN
 				m_data[i].~T();
 		if (size > m_size)
 			for (size_type i = m_size; i < size; i++)
-				new (m_data + i) T();
+				new (m_data + i) T(value);
 		m_size = size;
 		return {};
 	}

BAN/include/BAN/WeakPtr.h

@@ -0,0 +1,107 @@
+#pragma once
+
+#include <BAN/RefPtr.h>
+
+namespace BAN
+{
+
+	template<typename T>
+	class Weakable;
+
+	template<typename T>
+	class WeakPtr;
+
+	template<typename T>
+	class WeakLink : public RefCounted<WeakLink<T>>
+	{
+	public:
+		RefPtr<T> lock() { ASSERT(m_ptr); return raw_ptr(); }
+		T* raw_ptr() { return m_ptr; }
+
+		bool valid() const { return m_ptr; }
+		void invalidate() { m_ptr = nullptr; }
+
+	private:
+		WeakLink(T* ptr) : m_ptr(ptr) {}
+
+	private:
+		T* m_ptr;
+
+		friend class RefPtr<WeakLink<T>>;
+	};
+
+	template<typename T>
+	class Weakable
+	{
+	public:
+		~Weakable()
+		{
+			if (m_link)
+				m_link->invalidate();
+		}
+
+		ErrorOr<WeakPtr<T>> get_weak_ptr() const
+		{
+			if (!m_link)
+				m_link = TRY(RefPtr<WeakLink<T>>::create((T*)this));
+			return WeakPtr<T>(m_link);
+		}
+
+	private:
+		mutable RefPtr<WeakLink<T>> m_link;
+	};
+
+	template<typename T>
+	class WeakPtr
+	{
+	public:
+		WeakPtr() = default;
+		WeakPtr(WeakPtr&& other)		{ *this = move(other); }
+		WeakPtr(const WeakPtr& other)	{ *this = other; }
+		WeakPtr(const RefPtr<T>& other)	{ *this = other; }
+
+		WeakPtr& operator=(WeakPtr&& other)
+		{
+			clear();
+			m_link = move(other.m_link);
+			return *this;
+		}
+		WeakPtr& operator=(const WeakPtr& other)
+		{
+			clear();
+			m_link = other.m_link;
+			return *this;
+		}
+		WeakPtr& operator=(const RefPtr<T>& other)
+		{
+			clear();
+			if (other)
+				m_link = MUST(other->get_weak_ptr()).move_link();
+			return *this;
+		}
+
+		RefPtr<T> lock()
+		{
+			if (m_link->valid())
+				return m_link->lock();
+			return nullptr;
+		}
+
+		void clear() { m_link.clear(); }
+
+		bool valid() const { return m_link && m_link->valid(); }
+
+	private:
+		WeakPtr(const RefPtr<WeakLink<T>>& link)
+			: m_link(link)
+		{ }
+
+		RefPtr<WeakLink<T>>&& move_link() { return move(m_link); }
+
+	private:
+		RefPtr<WeakLink<T>> m_link;
+
+		friend class Weakable<T>;
+	};
+
+}

CMakeLists.txt

@@ -0,0 +1,118 @@
+cmake_minimum_required(VERSION 3.26)
+
+if(DEFINED ENV{BANAN_ARCH})
+	set(BANAN_ARCH $ENV{BANAN_ARCH})
+else()
+	set(BANAN_ARCH x86_64)
+endif()
+
+set(TOOLCHAIN_PREFIX ${CMAKE_SOURCE_DIR}/toolchain/local)
+
+set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_CXX_STANDARD_REQUIRED True)
+set(CMAKE_CXX_COMPILER ${TOOLCHAIN_PREFIX}/bin/${BANAN_ARCH}-banan_os-g++)
+set(CMAKE_CXX_COMPILER_WORKS True)
+
+set(CMAKE_C_COMPILER ${TOOLCHAIN_PREFIX}/bin/${BANAN_ARCH}-banan_os-gcc)
+set(CMAKE_C_COMPILER_WORKS True)
+
+if(NOT EXISTS ${CMAKE_CXX_COMPILER})
+	set(CMAKE_CXX_COMPILER g++)
+endif()
+
+if(DEFINED QEMU_ACCEL)
+	set(QEMU_ACCEL -accel ${QEMU_ACCEL})
+endif()
+
+add_compile_options(-mno-sse -mno-sse2)
+add_compile_definitions(__enable_sse=0)
+
+project(banan-os CXX)
+
+set(BANAN_BASE_SYSROOT ${CMAKE_SOURCE_DIR}/base-sysroot.tar.gz)
+set(BANAN_SYSROOT ${CMAKE_BINARY_DIR}/sysroot)
+set(BANAN_INCLUDE ${BANAN_SYSROOT}/usr/include)
+set(BANAN_LIB ${BANAN_SYSROOT}/usr/lib)
+set(BANAN_BIN ${BANAN_SYSROOT}/usr/bin)
+set(BANAN_BOOT ${BANAN_SYSROOT}/boot)
+set(DISK_IMAGE_PATH ${CMAKE_BINARY_DIR}/banan-os.img)
+
+add_subdirectory(kernel)
+add_subdirectory(BAN)
+add_subdirectory(libc)
+add_subdirectory(LibELF)
+add_subdirectory(userspace)
+
+add_custom_target(sysroot
+	COMMAND mkdir -p ${BANAN_SYSROOT}
+	COMMAND cd ${BANAN_SYSROOT} && sudo tar xf ${BANAN_BASE_SYSROOT}
+	USES_TERMINAL
+)
+
+add_custom_target(headers
+	DEPENDS kernel-headers
+	DEPENDS ban-headers
+	DEPENDS libc-headers
+	DEPENDS libelf-headers
+)
+
+add_custom_target(toolchain
+	COMMAND ${CMAKE_COMMAND} -E env SYSROOT="${BANAN_SYSROOT}" PREFIX="${TOOLCHAIN_PREFIX}" ARCH="${BANAN_ARCH}" ${CMAKE_SOURCE_DIR}/toolchain/build.sh
+	DEPENDS headers
+	USES_TERMINAL
+)
+
+add_custom_target(libstdc++
+	COMMAND ${CMAKE_COMMAND} -E env LIBSTDCPP="1" ${CMAKE_SOURCE_DIR}/toolchain/build.sh
+	DEPENDS libc-install
+	USES_TERMINAL
+)
+
+add_custom_target(image
+	COMMAND ${CMAKE_COMMAND} -E env SYSROOT="${BANAN_SYSROOT}" DISK_IMAGE_PATH="${DISK_IMAGE_PATH}" ${CMAKE_SOURCE_DIR}/image.sh
+	DEPENDS kernel-install
+	DEPENDS ban-install
+	DEPENDS libc-install
+	DEPENDS userspace-install
+	DEPENDS libelf-install
+	USES_TERMINAL
+)
+
+add_custom_target(image-full
+	COMMAND ${CMAKE_COMMAND} -E env SYSROOT="${BANAN_SYSROOT}" DISK_IMAGE_PATH="${DISK_IMAGE_PATH}" ${CMAKE_SOURCE_DIR}/image-full.sh
+	DEPENDS kernel-install
+	DEPENDS ban-install
+	DEPENDS libc-install
+	DEPENDS userspace-install
+	DEPENDS libelf-install
+	USES_TERMINAL
+)
+
+add_custom_target(check-fs
+	COMMAND ${CMAKE_COMMAND} -E env DISK_IMAGE_PATH="${DISK_IMAGE_PATH}" ${CMAKE_SOURCE_DIR}/check-fs.sh
+	USES_TERMINAL
+)
+
+add_custom_target(qemu
+	COMMAND ${CMAKE_COMMAND} -E env BANAN_ARCH="${BANAN_ARCH}" DISK_IMAGE_PATH="${DISK_IMAGE_PATH}" ${CMAKE_SOURCE_DIR}/qemu.sh -serial stdio ${QEMU_ACCEL}
+	DEPENDS image
+	USES_TERMINAL
+)
+
+add_custom_target(qemu-nographic
+	COMMAND ${CMAKE_COMMAND} -E env BANAN_ARCH="${BANAN_ARCH}" DISK_IMAGE_PATH="${DISK_IMAGE_PATH}" ${CMAKE_SOURCE_DIR}/qemu.sh -nographic ${QEMU_ACCEL}
+	DEPENDS image
+	USES_TERMINAL
+)
+
+add_custom_target(qemu-debug
+	COMMAND ${CMAKE_COMMAND} -E env BANAN_ARCH="${BANAN_ARCH}" DISK_IMAGE_PATH="${DISK_IMAGE_PATH}" ${CMAKE_SOURCE_DIR}/qemu.sh -serial stdio -d int -no-reboot
+	DEPENDS image
+	USES_TERMINAL
+)
+
+add_custom_target(bochs
+	COMMAND ${CMAKE_COMMAND} -E env DISK_IMAGE_PATH="${DISK_IMAGE_PATH}" ${CMAKE_SOURCE_DIR}/bochs.sh
+	DEPENDS image
+	USES_TERMINAL
+)

LICENCE

@@ -0,0 +1,24 @@
+BSD 2-Clause License
+
+Copyright (c) 2023, Oskari Alaranta
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

LibELF/CMakeLists.txt

@@ -0,0 +1,13 @@
+cmake_minimum_required(VERSION 3.26)
+
+project(LibELF CXX)
+
+add_custom_target(libelf-headers
+	COMMAND sudo rsync -a ${CMAKE_CURRENT_SOURCE_DIR}/include/ ${BANAN_INCLUDE}/
+	DEPENDS sysroot
+	USES_TERMINAL
+)
+
+add_custom_target(libelf-install
+	DEPENDS libelf-headers
+)

LibELF/LibELF/ELF.cpp

@@ -0,0 +1,406 @@
+#include <BAN/ScopeGuard.h>
+#include <LibELF/ELF.h>
+#include <LibELF/Values.h>
+
+#ifdef __is_kernel
+#include <kernel/FS/VirtualFileSystem.h>
+#include <kernel/Memory/PageTableScope.h>
+#include <kernel/Process.h>
+#endif
+
+#include <fcntl.h>
+
+#define ELF_PRINT_HEADERS 0
+
+#ifdef __is_kernel
+extern uint8_t g_kernel_end[];
+using namespace Kernel;
+#endif
+
+namespace LibELF
+{
+
+#ifdef __is_kernel
+	BAN::ErrorOr<BAN::UniqPtr<ELF>> ELF::load_from_file(BAN::RefPtr<Inode> inode)
+	{
+		BAN::Vector<uint8_t> buffer;
+		TRY(buffer.resize(inode->size()));
+
+		TRY(inode->read(0, buffer.data(), inode->size()));
+
+		ELF* elf_ptr = new ELF(BAN::move(buffer));
+		if (elf_ptr == nullptr)
+			return BAN::Error::from_errno(ENOMEM);
+
+		auto elf = BAN::UniqPtr<ELF>::adopt(elf_ptr);
+		TRY(elf->load());
+
+		return BAN::move(elf);
+	}
+#else
+	BAN::ErrorOr<ELF*> ELF::load_from_file(BAN::StringView file_path)
+	{
+		ELF* elf = nullptr;
+
+		{
+			BAN::Vector<uint8_t> data;
+
+			int fd = TRY(Kernel::Process::current().open(file_path, O_RDONLY));
+			BAN::ScopeGuard _([fd] { MUST(Kernel::Process::current().close(fd)); });
+
+			struct stat st;
+			TRY(Kernel::Process::current().fstat(fd, &st));
+
+			TRY(data.resize(st.st_size));
+
+			TRY(Kernel::Process::current().read(fd, data.data(), data.size()));
+
+			elf = new ELF(BAN::move(data));
+			ASSERT(elf);
+		}
+
+		if (auto res = elf->load(); res.is_error())
+		{
+			delete elf;
+			return res.error();
+		}
+
+		return elf;
+	}
+#endif
+
+	BAN::ErrorOr<void> ELF::load()
+	{
+		if (m_data.size() < EI_NIDENT)
+		{
+			dprintln("Too small ELF file");
+			return BAN::Error::from_errno(EINVAL);
+		}
+
+		if (m_data[EI_MAG0] != ELFMAG0 || 
+			m_data[EI_MAG1] != ELFMAG1 ||
+			m_data[EI_MAG2] != ELFMAG2 ||
+			m_data[EI_MAG3] != ELFMAG3)
+		{
+			dprintln("Invalid ELF header");
+			return BAN::Error::from_errno(EINVAL);
+		}
+
+		if (m_data[EI_DATA] != ELFDATA2LSB)
+		{
+			dprintln("Only little-endian is supported");
+			return BAN::Error::from_errno(EINVAL);
+		}
+
+		if (m_data[EI_VERSION] != EV_CURRENT)
+		{
+			dprintln("Invalid ELF version");
+			return BAN::Error::from_errno(EINVAL);
+		}
+
+		if (m_data[EI_CLASS] == ELFCLASS64)
+		{
+			if (m_data.size() <= sizeof(Elf64FileHeader))
+			{
+				dprintln("Too small ELF file");
+				return BAN::Error::from_errno(EINVAL);
+			}
+
+			auto& header = file_header64();
+			if (!parse_elf64_file_header(header))
+				return BAN::Error::from_errno(EINVAL);
+
+			for (size_t i = 0; i < header.e_phnum; i++)
+			{
+				auto& program_header = program_header64(i);
+				if (!parse_elf64_program_header(program_header))
+					return BAN::Error::from_errno(EINVAL);
+			}
+
+			for (size_t i = 1; i < header.e_shnum; i++)
+			{
+				auto& section_header = section_header64(i);
+				if (!parse_elf64_section_header(section_header))
+					return BAN::Error::from_errno(EINVAL);
+			}
+		}
+		else if (m_data[EI_CLASS] == ELFCLASS32)
+		{
+			if (m_data.size() <= sizeof(Elf32FileHeader))
+			{
+				dprintln("Too small ELF file");
+				return BAN::Error::from_errno(EINVAL);
+			}
+
+			auto& header = file_header32();
+			if (!parse_elf32_file_header(header))
+				return BAN::Error::from_errno(EINVAL);
+
+			for (size_t i = 0; i < header.e_phnum; i++)
+			{
+				auto& program_header = program_header32(i);
+				if (!parse_elf32_program_header(program_header))
+					return BAN::Error::from_errno(EINVAL);
+			}
+
+			for (size_t i = 1; i < header.e_shnum; i++)
+			{
+				auto& section_header = section_header32(i);
+				if (!parse_elf32_section_header(section_header))
+					return BAN::Error::from_errno(EINVAL);
+			}
+		}
+
+		return {};
+	}
+
+	bool ELF::is_x86_32() const { return m_data[EI_CLASS] == ELFCLASS32; }
+	bool ELF::is_x86_64() const { return m_data[EI_CLASS] == ELFCLASS64; }
+
+	/*
+
+		64 bit ELF
+
+	*/
+
+	const char* ELF::lookup_section_name64(uint32_t offset) const
+	{
+		return lookup_string64(file_header64().e_shstrndx, offset);
+	}
+
+	const char* ELF::lookup_string64(size_t table_index, uint32_t offset) const
+	{
+		if (table_index == SHN_UNDEF)
+			return nullptr;
+		auto& section_header = section_header64(table_index);
+		return (const char*)m_data.data() + section_header.sh_offset + offset;
+	}
+
+	bool ELF::parse_elf64_file_header(const Elf64FileHeader& header)
+	{
+		if (header.e_type != ET_EXEC)
+		{
+			dprintln("Only executable files are supported");
+			return false;
+		}
+
+		if (header.e_version != EV_CURRENT)
+		{
+			dprintln("Invalid ELF version");
+			return false;
+		}
+
+		return true;
+	}
+
+	bool ELF::parse_elf64_program_header(const Elf64ProgramHeader& header)
+	{
+#if ELF_PRINT_HEADERS
+		dprintln("program header");
+		dprintln("  type   {H}", header.p_type);
+		dprintln("  flags  {H}", header.p_flags);
+		dprintln("  offset {H}", header.p_offset);
+		dprintln("  vaddr  {H}", header.p_vaddr);
+		dprintln("  paddr  {H}", header.p_paddr);
+		dprintln("  filesz {}", header.p_filesz);
+		dprintln("  memsz  {}", header.p_memsz);
+		dprintln("  align  {}", header.p_align);
+#endif
+		(void)header;
+		return true;
+	}
+
+	bool ELF::parse_elf64_section_header(const Elf64SectionHeader& header)
+	{
+#if ELF_PRINT_HEADERS
+		if (auto* name = lookup_section_name64(header.sh_name))
+			dprintln("{}", name);
+
+		switch (header.sh_type)
+		{
+			case SHT_NULL:
+				dprintln("  SHT_NULL");
+				break;
+			case SHT_PROGBITS:
+				dprintln("  SHT_PROGBITS");
+				break;
+			case SHT_SYMTAB:
+				for (size_t i = 1; i < header.sh_size / header.sh_entsize; i++)
+				{
+					auto& symbol = ((const Elf64Symbol*)(m_data.data() + header.sh_offset))[i];
+					if (auto* name = lookup_string64(header.sh_link, symbol.st_name))
+						dprintln("  {}", name);
+				}
+				break;
+			case SHT_STRTAB:
+				dprintln("  SHT_STRTAB");
+				break;
+			case SHT_RELA:
+				dprintln("  SHT_RELA");
+				break;
+			case SHT_NOBITS:
+				dprintln("  SHT_NOBITS");
+				break;
+			case SHT_REL:
+				dprintln("  SHT_REL");
+				break;
+			case SHT_SHLIB:
+				dprintln("  SHT_SHLIB");
+				break;
+			case SHT_DYNSYM:
+				dprintln("  SHT_DYNSYM");
+				break;
+			default:
+				ASSERT(false);
+		}	
+#endif
+		(void)header;
+		return true;
+	}
+
+	const Elf64FileHeader& ELF::file_header64() const
+	{
+		ASSERT(is_x86_64());
+		return *(const Elf64FileHeader*)m_data.data();
+	}
+
+	const Elf64ProgramHeader& ELF::program_header64(size_t index) const
+	{
+		ASSERT(is_x86_64());
+		const auto& file_header = file_header64();
+		ASSERT(index < file_header.e_phnum);
+		return *(const Elf64ProgramHeader*)(m_data.data() + file_header.e_phoff + file_header.e_phentsize * index);
+	}
+
+	const Elf64SectionHeader& ELF::section_header64(size_t index) const
+	{
+		ASSERT(is_x86_64());
+		const auto& file_header = file_header64();
+		ASSERT(index < file_header.e_shnum);
+		return *(const Elf64SectionHeader*)(m_data.data() + file_header.e_shoff + file_header.e_shentsize * index);
+	}
+
+	/*
+
+		32 bit ELF
+
+	*/
+
+	const char* ELF::lookup_section_name32(uint32_t offset) const
+	{
+		return lookup_string32(file_header32().e_shstrndx, offset);
+	}
+
+	const char* ELF::lookup_string32(size_t table_index, uint32_t offset) const
+	{
+		if (table_index == SHN_UNDEF)
+			return nullptr;
+		auto& section_header = section_header32(table_index);
+		return (const char*)m_data.data() + section_header.sh_offset + offset;
+	}
+
+	bool ELF::parse_elf32_file_header(const Elf32FileHeader& header)
+	{
+		if (header.e_type != ET_EXEC)
+		{
+			dprintln("Only executable files are supported");
+			return false;
+		}
+
+		if (header.e_version != EV_CURRENT)
+		{
+			dprintln("Invalid ELF version");
+			return false;
+		}
+
+		return true;
+	}
+
+	bool ELF::parse_elf32_program_header(const Elf32ProgramHeader& header)
+	{
+#if ELF_PRINT_HEADERS
+		dprintln("program header");
+		dprintln("  type   {H}", header.p_type);
+		dprintln("  flags  {H}", header.p_flags);
+		dprintln("  offset {H}", header.p_offset);
+		dprintln("  vaddr  {H}", header.p_vaddr);
+		dprintln("  paddr  {H}", header.p_paddr);
+		dprintln("  filesz {}", header.p_filesz);
+		dprintln("  memsz  {}", header.p_memsz);
+		dprintln("  align  {}", header.p_align);
+#endif
+		(void)header;
+		return true;
+	}
+
+	bool ELF::parse_elf32_section_header(const Elf32SectionHeader& header)
+	{
+#if ELF_PRINT_HEADERS
+		if (auto* name = lookup_section_name32(header.sh_name))
+			dprintln("{}", name);
+
+		switch (header.sh_type)
+		{
+			case SHT_NULL:
+				dprintln("  SHT_NULL");
+				break;
+			case SHT_PROGBITS:
+				dprintln("  SHT_PROGBITS");
+				break;
+			case SHT_SYMTAB:
+				for (size_t i = 1; i < header.sh_size / header.sh_entsize; i++)
+				{
+					auto& symbol = ((const Elf32Symbol*)(m_data.data() + header.sh_offset))[i];
+					if (auto* name = lookup_string32(header.sh_link, symbol.st_name))
+						dprintln("  {}", name);
+				}
+				break;
+			case SHT_STRTAB:
+				dprintln("  SHT_STRTAB");
+				break;
+			case SHT_RELA:
+				dprintln("  SHT_RELA");
+				break;
+			case SHT_NOBITS:
+				dprintln("  SHT_NOBITS");
+				break;
+			case SHT_REL:
+				dprintln("  SHT_REL");
+				break;
+			case SHT_SHLIB:
+				dprintln("  SHT_SHLIB");
+				break;
+			case SHT_DYNSYM:
+				dprintln("  SHT_DYNSYM");
+				break;
+			default:
+				ASSERT(false);
+		}	
+#endif
+		(void)header;
+		return true;
+	}
+
+	const Elf32FileHeader& ELF::file_header32() const
+	{
+		ASSERT(is_x86_32());
+		return *(const Elf32FileHeader*)m_data.data();
+	}
+
+	const Elf32ProgramHeader& ELF::program_header32(size_t index) const
+	{
+		ASSERT(is_x86_32());
+		const auto& file_header = file_header32();
+		ASSERT(index < file_header.e_phnum);
+		return *(const Elf32ProgramHeader*)(m_data.data() + file_header.e_phoff + file_header.e_phentsize * index);
+	}
+
+	const Elf32SectionHeader& ELF::section_header32(size_t index) const
+	{
+		ASSERT(is_x86_32());
+		const auto& file_header = file_header32();
+		ASSERT(index < file_header.e_shnum);
+		return *(const Elf32SectionHeader*)(m_data.data() + file_header.e_shoff + file_header.e_shentsize * index);
+	}
+
+}

LibELF/LibELF/LoadableELF.cpp

@@ -0,0 +1,297 @@
+#include <BAN/ScopeGuard.h>
+#include <kernel/Memory/Heap.h>
+#include <kernel/LockGuard.h>
+#include <LibELF/LoadableELF.h>
+#include <LibELF/Values.h>
+
+namespace LibELF
+{
+
+	using namespace Kernel;
+
+	BAN::ErrorOr<BAN::UniqPtr<LoadableELF>> LoadableELF::load_from_inode(PageTable& page_table, BAN::RefPtr<Inode> inode)
+	{
+		auto* elf_ptr = new LoadableELF(page_table, inode);
+		if (elf_ptr == nullptr)
+			return BAN::Error::from_errno(ENOMEM);
+		auto elf = BAN::UniqPtr<LoadableELF>::adopt(elf_ptr);
+		TRY(elf->initialize());
+		return BAN::move(elf);
+	}
+
+	LoadableELF::LoadableELF(PageTable& page_table, BAN::RefPtr<Inode> inode)
+		: m_inode(inode)
+		, m_page_table(page_table)
+	{
+	}
+
+	LoadableELF::~LoadableELF()
+	{
+		for (const auto& program_header : m_program_headers)
+		{
+			switch (program_header.p_type)
+			{
+				case PT_NULL:
+					continue;
+				case PT_LOAD:
+				{
+					vaddr_t start = program_header.p_vaddr & PAGE_ADDR_MASK;
+					size_t pages = range_page_count(program_header.p_vaddr, program_header.p_memsz);
+					for (size_t i = 0; i < pages; i++)
+					{
+						paddr_t paddr = m_page_table.physical_address_of(start + i * PAGE_SIZE);
+						if (paddr != 0)
+							Heap::get().release_page(paddr);
+					}
+					m_page_table.unmap_range(start, pages * PAGE_SIZE);
+					break;
+				}
+				default:
+					ASSERT_NOT_REACHED();
+			}
+		}
+	}
+
+	BAN::ErrorOr<void> LoadableELF::initialize()
+	{
+		if ((size_t)m_inode->size() < sizeof(ElfNativeFileHeader))
+		{
+			dprintln("Too small file");
+			return BAN::Error::from_errno(ENOEXEC);
+		}
+
+		size_t nread = TRY(m_inode->read(0, &m_file_header, sizeof(m_file_header)));
+		ASSERT(nread == sizeof(m_file_header));
+
+		if (m_file_header.e_ident[EI_MAG0] != ELFMAG0 || 
+			m_file_header.e_ident[EI_MAG1] != ELFMAG1 ||
+			m_file_header.e_ident[EI_MAG2] != ELFMAG2 ||
+			m_file_header.e_ident[EI_MAG3] != ELFMAG3)
+		{
+			dprintln("Invalid magic in header");
+			return BAN::Error::from_errno(ENOEXEC);
+		}
+
+		if (m_file_header.e_ident[EI_DATA] != ELFDATA2LSB)
+		{
+			dprintln("Only little-endian is supported");
+			return BAN::Error::from_errno(ENOEXEC);
+		}
+
+		if (m_file_header.e_ident[EI_VERSION] != EV_CURRENT)
+		{
+			dprintln("Invalid version");
+			return BAN::Error::from_errno(ENOEXEC);
+		}
+
+#if ARCH(i386)
+		if (m_file_header.e_ident[EI_CLASS] != ELFCLASS32)
+#elif ARCH(x86_64)
+		if (m_file_header.e_ident[EI_CLASS] != ELFCLASS64)
+#endif
+		{
+			dprintln("Not in native format");	
+			return BAN::Error::from_errno(EINVAL);
+		}
+
+		if (m_file_header.e_type != ET_EXEC)
+		{
+			dprintln("Only executable files are supported");
+			return BAN::Error::from_errno(EINVAL);
+		}
+
+		if (m_file_header.e_version != EV_CURRENT)
+		{
+			dprintln("Unsupported version");
+			return BAN::Error::from_errno(EINVAL);
+		}
+
+		ASSERT(m_file_header.e_phentsize <= sizeof(ElfNativeProgramHeader));
+
+		TRY(m_program_headers.resize(m_file_header.e_phnum));
+		for (size_t i = 0; i < m_file_header.e_phnum; i++)
+		{
+			TRY(m_inode->read(m_file_header.e_phoff + m_file_header.e_phentsize * i, &m_program_headers[i], m_file_header.e_phentsize));
+
+			const auto& pheader = m_program_headers[i];
+			if (pheader.p_type != PT_NULL && pheader.p_type != PT_LOAD)
+			{
+				dprintln("Unsupported program header type {}", pheader.p_type);
+				return BAN::Error::from_errno(ENOTSUP);
+			}
+			if (pheader.p_memsz < pheader.p_filesz)
+			{
+				dprintln("Invalid program header");
+				return BAN::Error::from_errno(EINVAL);
+			}
+
+			m_virtual_page_count += BAN::Math::div_round_up<size_t>((pheader.p_vaddr % PAGE_SIZE) + pheader.p_memsz, PAGE_SIZE);
+		}
+
+		return {};
+	}
+
+	vaddr_t LoadableELF::entry_point() const
+	{
+		return m_file_header.e_entry;
+	}
+
+	bool LoadableELF::contains(vaddr_t address) const
+	{
+		for (const auto& program_header : m_program_headers)
+		{
+			switch (program_header.p_type)
+			{
+				case PT_NULL:
+					continue;
+				case PT_LOAD:
+					if (program_header.p_vaddr <= address && address < program_header.p_vaddr + program_header.p_memsz)
+						return true;
+					break;
+				default:
+					ASSERT_NOT_REACHED();
+			}
+		}
+		return false;
+	}
+
+	void LoadableELF::reserve_address_space()
+	{
+		for (const auto& program_header : m_program_headers)
+		{
+			switch (program_header.p_type)
+			{
+				case PT_NULL:
+					break;
+				case PT_LOAD:
+				{
+					vaddr_t page_vaddr = program_header.p_vaddr & PAGE_ADDR_MASK;
+					size_t pages = range_page_count(program_header.p_vaddr, program_header.p_memsz);
+					ASSERT(m_page_table.reserve_range(page_vaddr, pages * PAGE_SIZE));
+					break;
+				}
+				default:
+					ASSERT_NOT_REACHED();
+			}
+		}
+	}
+
+	BAN::ErrorOr<void> LoadableELF::load_page_to_memory(vaddr_t address)
+	{
+		for (const auto& program_header : m_program_headers)
+		{
+			switch (program_header.p_type)
+			{
+				case PT_NULL:
+					break;
+				case PT_LOAD:
+				{
+					if (!(program_header.p_vaddr <= address && address < program_header.p_vaddr + program_header.p_memsz))
+						continue;
+
+					PageTable::flags_t flags = PageTable::Flags::UserSupervisor | PageTable::Flags::Present;
+					if (program_header.p_flags & LibELF::PF_W)
+						flags |= PageTable::Flags::ReadWrite;
+					if (program_header.p_flags & LibELF::PF_X)
+						flags |= PageTable::Flags::Execute;
+
+					vaddr_t vaddr = address & PAGE_ADDR_MASK;
+					paddr_t paddr = Heap::get().take_free_page();
+					if (paddr == 0)
+						return BAN::Error::from_errno(ENOMEM);
+
+					m_page_table.map_page_at(paddr, vaddr, flags);
+					m_physical_page_count++;
+
+					memset((void*)vaddr, 0x00, PAGE_SIZE);
+					
+					if (vaddr / PAGE_SIZE < BAN::Math::div_round_up<size_t>(program_header.p_vaddr + program_header.p_filesz, PAGE_SIZE))
+					{
+						size_t vaddr_offset = 0;
+						if (vaddr < program_header.p_vaddr)
+							vaddr_offset = program_header.p_vaddr - vaddr;
+						
+						size_t file_offset = 0;
+						if (vaddr > program_header.p_vaddr)
+							file_offset = vaddr - program_header.p_vaddr;
+
+						size_t bytes = BAN::Math::min<size_t>(PAGE_SIZE - vaddr_offset, program_header.p_filesz - file_offset);
+						TRY(m_inode->read(program_header.p_offset + file_offset, (void*)(vaddr + vaddr_offset), bytes));
+					}
+
+					return {};
+				}
+				default:
+					ASSERT_NOT_REACHED();
+			}
+		}
+		ASSERT_NOT_REACHED();
+	}
+
+	
+	BAN::ErrorOr<BAN::UniqPtr<LoadableELF>> LoadableELF::clone(Kernel::PageTable& new_page_table)
+	{
+		auto* elf_ptr = new LoadableELF(new_page_table, m_inode);
+		if (elf_ptr == nullptr)
+			return BAN::Error::from_errno(ENOMEM);
+		auto elf = BAN::UniqPtr<LoadableELF>::adopt(elf_ptr);
+
+		memcpy(&elf->m_file_header, &m_file_header, sizeof(ElfNativeFileHeader));
+
+		TRY(elf->m_program_headers.resize(m_program_headers.size()));
+		memcpy(elf->m_program_headers.data(), m_program_headers.data(), m_program_headers.size() * sizeof(ElfNativeProgramHeader));
+
+		elf->reserve_address_space();
+
+		ASSERT(&PageTable::current() == &m_page_table);
+		LockGuard _(m_page_table);
+		ASSERT(m_page_table.is_page_free(0));
+
+		for (const auto& program_header : m_program_headers)
+		{
+			switch (program_header.p_type)
+			{
+				case PT_NULL:
+					break;
+				case PT_LOAD:
+				{
+					if (!(program_header.p_flags & LibELF::PF_W))
+						continue;
+
+					PageTable::flags_t flags = PageTable::Flags::UserSupervisor | PageTable::Flags::Present;
+					if (program_header.p_flags & LibELF::PF_W)
+						flags |= PageTable::Flags::ReadWrite;
+					if (program_header.p_flags & LibELF::PF_X)
+						flags |= PageTable::Flags::Execute;
+
+					vaddr_t start = program_header.p_vaddr & PAGE_ADDR_MASK;
+					size_t pages = range_page_count(program_header.p_vaddr, program_header.p_memsz);
+
+					for (size_t i = 0; i < pages; i++)
+					{
+						if (m_page_table.physical_address_of(start + i * PAGE_SIZE) == 0)
+							continue;
+
+						paddr_t paddr = Heap::get().take_free_page();
+						if (paddr == 0)
+							return BAN::Error::from_errno(ENOMEM);
+
+						m_page_table.map_page_at(paddr, 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
+						memcpy((void*)0, (void*)(start + i * PAGE_SIZE), PAGE_SIZE);
+						m_page_table.unmap_page(0);
+
+						new_page_table.map_page_at(paddr, start + i * PAGE_SIZE, flags);
+						elf->m_physical_page_count++;
+					}
+
+					break;
+				}
+				default:
+					ASSERT_NOT_REACHED();
+			}
+		}
+
+		return elf;
+	}
+
+}

LibELF/include/LibELF/ELF.h

@@ -0,0 +1,89 @@
+#pragma once
+
+#ifdef __is_kernel
+#include <kernel/FS/Inode.h>
+#include <kernel/Memory/VirtualRange.h>
+#endif
+
+#include <BAN/StringView.h>
+#include <BAN/UniqPtr.h>
+#include <BAN/Vector.h>
+#include <kernel/Arch.h>
+#include "Types.h"
+
+namespace LibELF
+{
+
+	class ELF
+	{
+	public:
+#ifdef __is_kernel
+		static BAN::ErrorOr<BAN::UniqPtr<ELF>> load_from_file(BAN::RefPtr<Kernel::Inode>);
+#else
+		static BAN::ErrorOr<BAN::UniqPtr<ELF>> load_from_file(BAN::StringView);
+#endif
+
+		const Elf64FileHeader& file_header64() const;
+		const Elf64ProgramHeader& program_header64(size_t) const;
+		const Elf64SectionHeader& section_header64(size_t) const;
+		const char* lookup_section_name64(uint32_t) const;
+		const char* lookup_string64(size_t, uint32_t) const;
+#if ARCH(x86_64)
+		const Elf64FileHeader& file_header_native() const { return file_header64(); }
+		const Elf64ProgramHeader& program_header_native(size_t index) const { return program_header64(index); }
+		const Elf64SectionHeader& section_header_native(size_t index) const { return section_header64(index); }
+		const char* lookup_section_name_native(uint32_t offset) const { return lookup_section_name64(offset); }
+		const char* lookup_string_native(size_t table_index, uint32_t offset) const { return lookup_string64(table_index, offset); }
+		bool is_native() const { return is_x86_64(); }
+#endif
+
+		const Elf32FileHeader& file_header32() const;
+		const Elf32ProgramHeader& program_header32(size_t) const;
+		const Elf32SectionHeader& section_header32(size_t) const;
+		const char* lookup_section_name32(uint32_t) const;
+		const char* lookup_string32(size_t, uint32_t) const;
+#if ARCH(i386)
+		const Elf32FileHeader& file_header_native() const { return file_header32(); }
+		const Elf32ProgramHeader& program_header_native(size_t index) const { return program_header32(index); }
+		const Elf32SectionHeader& section_header_native(size_t index) const { return section_header32(index); }
+		const char* lookup_section_name_native(uint32_t offset) const { return lookup_section_name32(offset); }
+		const char* lookup_string_native(size_t table_index, uint32_t offset) const { return lookup_string32(table_index, offset); }
+		bool is_native() const { return is_x86_32(); }
+#endif
+
+		const uint8_t* data() const { return m_data.data(); }
+
+		bool is_x86_32() const;
+		bool is_x86_64() const;
+
+	private:
+//#ifdef __is_kernel
+//		ELF(BAN::UniqPtr<Kernel::VirtualRange>&& storage, size_t size)
+//			: m_storage(BAN::move(storage))
+//			, m_data((const uint8_t*)m_storage->vaddr(), size)
+//		{}
+//#else
+		ELF(BAN::Vector<uint8_t>&& data)
+			: m_data(BAN::move(data))
+		{}
+//#endif
+		BAN::ErrorOr<void> load();
+		
+		bool parse_elf64_file_header(const Elf64FileHeader&);
+		bool parse_elf64_program_header(const Elf64ProgramHeader&);
+		bool parse_elf64_section_header(const Elf64SectionHeader&);
+
+		bool parse_elf32_file_header(const Elf32FileHeader&);
+		bool parse_elf32_program_header(const Elf32ProgramHeader&);
+		bool parse_elf32_section_header(const Elf32SectionHeader&);
+
+	private:
+//#ifdef __is_kernel
+//		BAN::UniqPtr<Kernel::VirtualRange> m_storage;
+//		BAN::Span<const uint8_t> m_data;
+//#else
+		const BAN::Vector<uint8_t> m_data;
+//#endif
+	};
+
+}

LibELF/include/LibELF/LoadableELF.h

@@ -0,0 +1,52 @@
+#pragma once
+
+#ifndef __is_kernel
+#error "This is kernel only header"
+#endif
+
+#include <BAN/UniqPtr.h>
+#include <BAN/Vector.h>
+
+#include <kernel/FS/Inode.h>
+#include <kernel/Memory/PageTable.h>
+
+#include <LibELF/Types.h>
+
+namespace LibELF
+{
+
+	class LoadableELF
+	{
+		BAN_NON_COPYABLE(LoadableELF);
+		BAN_NON_MOVABLE(LoadableELF);
+
+	public:
+		static BAN::ErrorOr<BAN::UniqPtr<LoadableELF>> load_from_inode(Kernel::PageTable&, BAN::RefPtr<Kernel::Inode>);
+		~LoadableELF();
+
+		Kernel::vaddr_t entry_point() const;
+
+		bool contains(Kernel::vaddr_t address) const;
+		void reserve_address_space();
+
+		BAN::ErrorOr<void> load_page_to_memory(Kernel::vaddr_t address);
+
+		BAN::ErrorOr<BAN::UniqPtr<LoadableELF>> clone(Kernel::PageTable&);
+
+		size_t virtual_page_count() const { return m_virtual_page_count; }
+		size_t physical_page_count() const { return m_physical_page_count; }
+
+	private:
+		LoadableELF(Kernel::PageTable&, BAN::RefPtr<Kernel::Inode>);
+		BAN::ErrorOr<void> initialize();
+
+	private:
+		BAN::RefPtr<Kernel::Inode>			m_inode;
+		Kernel::PageTable&					m_page_table;
+		ElfNativeFileHeader					m_file_header;
+		BAN::Vector<ElfNativeProgramHeader>	m_program_headers;
+		size_t m_virtual_page_count = 0;
+		size_t m_physical_page_count = 0;
+	};
+
+}

LibELF/include/LibELF/Types.h

@@ -0,0 +1,189 @@
+#pragma once
+
+#include <kernel/Arch.h>
+
+#include <stdint.h>
+
+namespace LibELF
+{
+
+	using Elf32Addr = uint32_t;
+	using Elf32Off = uint32_t;
+	using Elf32Half = uint16_t;
+	using Elf32Word = uint32_t;
+	using Elf32Sword = int32_t;
+
+	struct Elf32FileHeader
+	{
+		unsigned char e_ident[16];
+		Elf32Half e_type;
+		Elf32Half e_machine;
+		Elf32Word e_version;
+		Elf32Addr e_entry;
+		Elf32Off e_phoff;
+		Elf32Off e_shoff;
+		Elf32Word e_flags;
+		Elf32Half e_ehsize;
+		Elf32Half e_phentsize;
+		Elf32Half e_phnum;
+		Elf32Half e_shentsize;
+		Elf32Half e_shnum;
+		Elf32Half e_shstrndx;
+	};
+
+	struct Elf32SectionHeader
+	{
+		Elf32Word sh_name;
+		Elf32Word sh_type;
+		Elf32Word sh_flags;
+		Elf32Addr sh_addr;
+		Elf32Off sh_offset;
+		Elf32Word sh_size;
+		Elf32Word sh_link;
+		Elf32Word sh_info;
+		Elf32Word sh_addralign;
+		Elf32Word sh_entsize;
+	};
+
+	struct Elf32Symbol
+	{
+		Elf32Word st_name;
+		Elf32Addr st_value;
+		Elf32Word st_size;
+		unsigned char st_info;
+		unsigned char st_other;
+		Elf32Half st_shndx;
+	};
+
+	struct Elf32Relocation
+	{
+		Elf32Addr r_offset;
+		Elf32Word r_info;
+	};
+
+	struct Elf32RelocationA
+	{
+		Elf32Addr r_offset;
+		Elf32Word r_info;
+		Elf32Sword r_addend;
+	};
+
+	struct Elf32ProgramHeader
+	{
+		Elf32Word p_type;
+		Elf32Off p_offset;
+		Elf32Addr p_vaddr;
+		Elf32Addr p_paddr;
+		Elf32Word p_filesz;
+		Elf32Word p_memsz;
+		Elf32Word p_flags;
+		Elf32Word p_align;
+	};
+
+	using Elf64Addr = uint64_t;
+	using Elf64Off = uint64_t;
+	using Elf64Half = uint16_t;
+	using Elf64Word = uint32_t;
+	using Elf64Sword = int32_t;
+	using Elf64Xword = uint64_t;
+	using Elf64Sxword = int64_t;
+
+	struct Elf64FileHeader
+	{
+		unsigned char e_ident[16];
+		Elf64Half e_type;
+		Elf64Half e_machine;
+		Elf64Word e_version;
+		Elf64Addr e_entry;
+		Elf64Off e_phoff;
+		Elf64Off e_shoff;
+		Elf64Word e_flags;
+		Elf64Half e_ehsize;
+		Elf64Half e_phentsize;
+		Elf64Half e_phnum;
+		Elf64Half e_shentsize;
+		Elf64Half e_shnum;
+		Elf64Half e_shstrndx;
+	};
+
+	struct Elf64SectionHeader
+	{
+		Elf64Word sh_name;
+		Elf64Word sh_type;
+		Elf64Xword sh_flags;
+		Elf64Addr sh_addr;
+		Elf64Off sh_offset;
+		Elf64Xword sh_size;
+		Elf64Word sh_link;
+		Elf64Word sh_info;
+		Elf64Xword sh_addralign;
+		Elf64Xword sh_entsize;
+	};
+
+	struct Elf64Symbol
+	{
+		Elf64Word st_name;
+		unsigned char st_info;
+		unsigned char st_other;
+		Elf64Half st_shndx;
+		Elf64Addr st_value;
+		Elf64Xword st_size;
+	};
+
+	struct Elf64Relocation
+	{
+		Elf64Addr r_offset;
+		Elf64Xword r_info;
+	};
+
+	struct Elf64RelocationA
+	{
+		Elf64Addr r_offset;
+		Elf64Xword r_info;
+		Elf64Sxword r_addend;
+	};
+
+	struct Elf64ProgramHeader
+	{
+		Elf64Word p_type;
+		Elf64Word p_flags;
+		Elf64Off p_offset;
+		Elf64Addr p_vaddr;
+		Elf64Addr p_paddr;
+		Elf64Xword p_filesz;
+		Elf64Xword p_memsz;
+		Elf64Xword p_align;
+	};
+
+
+#if ARCH(i386)
+	using ElfNativeAddr = Elf32Addr;
+	using ElfNativeOff = Elf32Off;
+	using ElfNativeHalf = Elf32Half;
+	using ElfNativeWord = Elf32Word;
+	using ElfNativeSword = Elf32Sword;
+	using ElfNativeXword = Elf32Xword;
+	using ElfNativeSxword = Elf32Sxword;
+	using ElfNativeFileHeader = Elf32FileHeader;
+	using ElfNativeSectionHeader = Elf32SectionHeader;
+	using ElfNativeSymbol = Elf32Symbol;
+	using ElfNativeRelocation = Elf32Relocation;
+	using ElfNativeRelocationA = Elf32RelocationA;
+	using ElfNativeProgramHeader = Elf32ProgramHeader;
+#elif ARCH(x86_64)
+	using ElfNativeAddr = Elf64Addr;
+	using ElfNativeOff = Elf64Off;
+	using ElfNativeHalf = Elf64Half;
+	using ElfNativeWord = Elf64Word;
+	using ElfNativeSword = Elf64Sword;
+	using ElfNativeXword = Elf64Xword;
+	using ElfNativeSxword = Elf64Sxword;
+	using ElfNativeFileHeader = Elf64FileHeader;
+	using ElfNativeSectionHeader = Elf64SectionHeader;
+	using ElfNativeSymbol = Elf64Symbol;
+	using ElfNativeRelocation = Elf64Relocation;
+	using ElfNativeRelocationA = Elf64RelocationA;
+	using ElfNativeProgramHeader = Elf64ProgramHeader;
+#endif
+
+}

LibELF/include/LibELF/Values.h

@@ -0,0 +1,140 @@
+#pragma once
+
+namespace LibELF
+{
+
+	enum ELF_Ident
+	{
+		ELFMAG0			= 0x7F,
+		ELFMAG1			= 'E',
+		ELFMAG2			= 'L',
+		ELFMAG3			= 'F',
+
+		ELFCLASSNONE	= 0,
+		ELFCLASS32		= 1,
+		ELFCLASS64		= 2,
+
+		ELFDATANONE		= 0,
+		ELFDATA2LSB		= 1,
+		ELFDATA2MSB		= 2,
+	};
+
+	enum ELF_EI
+	{
+		EI_MAG0			= 0,
+		EI_MAG1			= 1,
+		EI_MAG2			= 2,
+		EI_MAG3			= 3,
+		EI_CLASS		= 4,
+		EI_DATA			= 5,
+		EI_VERSION		= 6,
+		EI_OSABI		= 7,
+		EI_ABIVERSION	= 8,
+		EI_NIDENT		= 16,
+	};
+
+	enum ELF_ET
+	{
+		ET_NONE		= 0,
+		ET_REL		= 1,
+		ET_EXEC		= 2,
+		ET_DYN		= 3,
+		ET_CORE		= 4,
+		ET_LOOS		= 0xfe00,
+		ET_HIOS		= 0xfeff,
+		ET_LOPROC	= 0xff00,
+		ET_HIPROC	= 0xffff,
+	};
+
+	enum ELF_EV
+	{
+		EV_NONE		= 0,
+		EV_CURRENT	= 1,
+	};
+
+	enum ELF_SHT
+	{
+		SHT_NULL		= 0,
+		SHT_PROGBITS	= 1,
+		SHT_SYMTAB		= 2,
+		SHT_STRTAB		= 3,
+		SHT_RELA		= 4,
+		SHT_NOBITS		= 8,
+		SHT_REL			= 9,
+		SHT_SHLIB		= 10,
+		SHT_DYNSYM		= 11,
+		SHT_LOOS		= 0x60000000,
+		SHT_HIOS		= 0x6FFFFFFF,
+		SHT_LOPROC		= 0x70000000,
+		SHT_HIPROC		= 0x7FFFFFFF,
+	};
+
+	enum ELF_SHF
+	{
+		SHF_WRITE		= 0x1,
+		SHF_ALLOC		= 0x2,
+		SHF_EXECINSTR	= 0x4,
+		SHF_MASKOS		= 0x0F000000,
+		SHF_MASKPROC	= 0xF0000000,
+	};
+
+	enum ELF_SHN
+	{
+		SHN_UNDEF	= 0,
+		SHN_LOPROC	= 0xFF00,
+		SHN_HIPROC	= 0xFF1F,
+		SHN_LOOS	= 0xFF20,
+		SHN_HIOS	= 0xFF3F,
+		SHN_ABS		= 0xFFF1,
+		SHN_COMMON	= 0xFFF2,
+	};
+
+	enum ELF_STB
+	{
+		STB_LOCAL	= 0,
+		STB_GLOBAL	= 1,
+		STB_WEAK	= 2,
+		STB_LOOS	= 10,
+		STB_HIOS	= 12,
+		STB_LOPROC	= 13,
+		STB_HIPROC	= 15,
+	};
+
+	enum ELF_STT
+	{
+		STT_NOTYPE	= 0,
+		STT_OBJECT	= 1,
+		STT_FUNC	= 2,
+		STT_SECTION	= 3,
+		STT_FILE	= 4,
+		STT_LOOS	= 10,
+		STT_HIOS	= 12,
+		STT_LOPROC	= 13,
+		STT_HIPROC	= 15,
+	};
+
+	enum ELF_PT
+	{
+		PT_NULL		= 0,
+		PT_LOAD		= 1,
+		PT_DYNAMIC	= 2,
+		PT_INTERP	= 3,
+		PT_NOTE		= 4,
+		PT_SHLIB	= 5,
+		PT_PHDR		= 6,
+		PT_LOOS		= 0x60000000,
+		PT_HIOS		= 0x6FFFFFFF,
+		PT_LOPROC	= 0x70000000,
+		PT_HIPROC	= 0x7FFFFFFF,
+	};
+
+	enum ELF_PF
+	{
+		PF_X		= 0x1,
+		PF_W		= 0x2,
+		PF_R		= 0x4,
+		PF_MASKOS	= 0x00FF0000,
+		PF_MASKPROC	= 0xFF000000,
+	};
+
+}

PreLoad.cmake

@@ -0,0 +1 @@
+set(CMAKE_GENERATOR "Ninja" CACHE INTERNAL "" FORCE)

README.md

@@ -0,0 +1,55 @@
+![license](https://img.shields.io/github/license/bananymous/banan-os)
+
+# banan-os
+
+This is my hobby operating system written in C++. Currently supports only x86_64 architecture. We have a read-only ext2 filesystem, read-write ramfs, IDE disk drivers in ATA PIO mode, userspace processes, executable loading from ELF format, linear VBE graphics and multithreaded processing on single core.
+
+![screenshot from qemu running banan-os](assets/banan-os.png)
+
+## Code structure
+
+Each major component and library has its own subdirectory (kernel, userspace, libc, ...). Each directory contains directory *include*, which has **all** of the header files of the component. Every header is included by its absolute path.
+
+## Building
+
+There does not exist a complete list of needed packages for building. From the top of my head I can say that *cmake*, *ninja*, *make*, *grub*, *rsync* and emulator (*qemu* or *bochs*) are needed.
+
+You can and *should* pass cmake variable QEMU_ACCEL set to proper accelerator to cmake commands. For example on Linux this means adding -DQEMU_ACCEL=kvm to the end of all cmake commands. 
+
+Create the build directory and cofigure cmake
+```sh
+mkdir build
+cd build
+cmake ..
+```
+
+To build the toolchain for this os. You can run the following command.
+> ***NOTE:*** The following step has to be done only once. This might take a long time since we are compiling binutils and gcc.
+```sh
+ninja toolchain
+cmake --fresh .. # We need to reconfigure cmake to use the new compiler
+ninja libstdc++
+```
+
+To build the os itself you can run either of the following commands. You will need root access since the sysroot has "proper" permissions.
+```sh
+ninja qemu
+ninja bochs
+```
+
+You can also build the kernel or disk image without running it:
+```sh
+ninja kernel
+ninja image
+```
+
+If you have corrupted your disk image or want to create new one, you can either manually delete *banan-os.img* and cmake will automatically create you a new one or you can run the following command.
+```sh
+ninja image-full
+```
+
+> ***NOTE*** ```ninja clean``` has to be ran with root permissions, since it deletes the root filesystem.
+
+### Contributing
+
+Currently I don't accept contributions to this repository unless explicitly told otherwise. This is a learning project for me and I want to do everything myself. Feel free to fork/clone this repo and tinker with it yourself.

bochs.sh

@@ -1,7 +1,6 @@
-#!/bin/sh
+#!/bin/bash
 set -e
-. ./disk.sh
- 
+
 BOCHS_CONFIG_FILE=bochsrc
 COM1_TERMINAL=kitty
 COM1_DEVICE_FILE=com1-term-device
@@ -15,7 +14,7 @@ COM1_DEVICE=$(cat $COM1_DEVICE_FILE)
 rm $COM1_DEVICE_FILE
 
 cat > $BOCHS_CONFIG_FILE << EOF
-ata0-master: type=disk, path=banan-os.img, status=inserted
+ata0-master: type=disk, path=$DISK_IMAGE_PATH, status=inserted
 boot: disk
 clock: sync=realtime, time0=local
 display_library: x, options="gui_debug"

build.sh

@@ -1,7 +0,0 @@
-#!/bin/sh
-set -e
-. ./headers.sh
- 
-for PROJECT in $PROJECTS; do
-  (cd $PROJECT && DESTDIR="$SYSROOT" $MAKE install)
-done

check-fs.sh

@@ -0,0 +1,10 @@
+#!/bin/bash
+
+set -e
+
+LOOP_DEV=$(sudo losetup -f --show $DISK_IMAGE_PATH)
+sudo partprobe $LOOP_DEV
+
+sudo fsck.ext2 -fn ${LOOP_DEV}p2 || true
+
+sudo losetup -d $LOOP_DEV

clean.sh

@@ -1,11 +0,0 @@
-#!/bin/sh
-set -e
-. ./config.sh
- 
-for PROJECT in $PROJECTS; do
-  (cd $PROJECT && $MAKE clean)
-done
- 
-rm -rf sysroot
-rm -rf isodir
-rm -rf banan-os.img

config.sh

@@ -1,33 +0,0 @@
-SYSTEM_HEADER_PROJECTS="libc BAN kernel"
-PROJECTS="libc BAN kernel"
- 
-export MAKE=${MAKE:-make}
-export HOST=${HOST:-$(./default-host.sh)}
- 
-export AR=${HOST}-ar
-export AS=${HOST}-as
-export CC=${HOST}-gcc
-export CXX=${HOST}-g++
- 
-export PREFIX=/usr
-export EXEC_PREFIX=$PREFIX
-export BOOTDIR=/boot
-export LIBDIR=$EXEC_PREFIX/lib
-export INCLUDEDIR=$PREFIX/include
- 
-export CFLAGS='-O2 -g'
-export CPPFLAGS='--std=c++20 -Wno-literal-suffix'
- 
-export UBSAN=0
-
-# Configure the cross-compiler to use the desired system root.
-export SYSROOT="$(pwd)/sysroot"
-export CC="$CC --sysroot=$SYSROOT"
-export CXX="$CXX --sysroot=$SYSROOT"
- 
-# Work around that the -elf gcc targets doesn't have a system include directory
-# because it was configured with --without-headers rather than --with-sysroot.
-if echo "$HOST" | grep -Eq -- '-elf($|-)'; then
-  export CC="$CC -isystem=$INCLUDEDIR"
-  export CXX="$CXX -isystem=$INCLUDEDIR"
-fi

default-host.sh

@@ -1,2 +0,0 @@
-#!/bin/sh
-echo x86_64-elf

disk.sh

@@ -1,67 +0,0 @@
-#!/bin/sh
-set -e
-. ./build.sh
-
-DISK_NAME=banan-os.img
-DISK_SIZE=$[50 * 1024 * 1024]
-MOUNT_DIR=/mnt
-
-dd if=/dev/zero of=$DISK_NAME bs=512 count=$[$DISK_SIZE / 512]
-
-sed -e 's/\s*\([-\+[:alnum:]]*\).*/\1/' << EOF | fdisk $DISK_NAME
-  g     # gpt
-  n     # new partition
-  1     # partition number 1
-        # default (from the beginning of the disk)
-  +1MiB # bios boot partiton size
-  n     # new partition
-  2     # partition number 2
-        # default (right after bios boot partition)
-		# default (to the end of disk)
-  t     # set type
-  1     # ... of partition 1
-  4     # bios boot partition
-  t     # set type
-  2     # ... of partition 2
-  20    # Linux filesystem
-  x		# expert menu
-  n		# partition name
-  2		# ... of partition 2
-  banan-root
-  r		# back to main menu
-  w     # write changes
-EOF
-
-LOOP_DEV=$(sudo losetup -f --show $DISK_NAME)
-sudo partprobe $LOOP_DEV
-
-PARTITION1=${LOOP_DEV}p1
-PARTITION2=${LOOP_DEV}p2
-
-sudo mkfs.ext2 $PARTITION2
-
-sudo mount $PARTITION2 $MOUNT_DIR
-
-sudo cp -r ${SYSROOT}/* ${MOUNT_DIR}/
-sudo mkdir -p ${MOUNT_DIR}/usr/share/
-sudo cp -r fonts ${MOUNT_DIR}/usr/share/
-
-sudo grub-install --no-floppy --target=i386-pc --modules="normal ext2 multiboot" --boot-directory=${MOUNT_DIR}/boot $LOOP_DEV
-
-echo -e '
-menuentry "banan-os" {
-	multiboot /boot/banan-os.kernel
-}
-menuentry "banan-os (no serial)" {
-	multiboot /boot/banan-os.kernel noserial
-}
-menuentry "banan-os (no apic)" {
-	multiboot /boot/banan-os.kernel noapic
-}
-menuentry "banan-os (no apic, no serial)" {
-	multiboot /boot/banan-os.kernel noapic noserial
-}
-' | sudo tee ${MOUNT_DIR}/boot/grub/grub.cfg
-
-sudo umount $MOUNT_DIR
-sudo losetup -d $LOOP_DEV

headers.sh

@@ -1,9 +0,0 @@
-#!/bin/sh
-set -e
-. ./config.sh
- 
-mkdir -p "$SYSROOT"
- 
-for PROJECT in $SYSTEM_HEADER_PROJECTS; do
-  (cd $PROJECT && DESTDIR="$SYSROOT" $MAKE install-headers)
-done

image-full.sh

@@ -0,0 +1,41 @@
+#!/bin/bash
+set -e
+
+DISK_SIZE=$[50 * 1024 * 1024]
+MOUNT_DIR=/mnt
+
+truncate -s 0 $DISK_IMAGE_PATH
+truncate -s $DISK_SIZE $DISK_IMAGE_PATH
+
+sed -e 's/\s*\([-\+[:alnum:]]*\).*/\1/' << EOF | fdisk $DISK_IMAGE_PATH > /dev/null
+  g     # gpt
+  n     # new partition
+  1     # partition number 1
+        # default (from the beginning of the disk)
+  +1MiB # bios boot partiton size
+  n     # new partition
+  2     # partition number 2
+        # default (right after bios boot partition)
+		# default (to the end of disk)
+  t     # set type
+  1     # ... of partition 1
+  4     # bios boot partition
+  t     # set type
+  2     # ... of partition 2
+  20    # Linux filesystem
+  w     # write changes
+EOF
+
+LOOP_DEV=$(sudo losetup -f --show $DISK_IMAGE_PATH)
+sudo partprobe $LOOP_DEV
+
+PARTITION1=${LOOP_DEV}p1
+PARTITION2=${LOOP_DEV}p2
+
+sudo mkfs.ext2 -d $SYSROOT -b 1024 -q $PARTITION2
+
+sudo mount $PARTITION2 $MOUNT_DIR
+sudo grub-install --no-floppy --target=i386-pc --modules="normal ext2 multiboot" --boot-directory=${MOUNT_DIR}/boot $LOOP_DEV
+sudo umount $MOUNT_DIR
+
+sudo losetup -d $LOOP_DEV

image.sh

@@ -0,0 +1,22 @@
+#!/bin/bash
+set -e
+
+if [ ! -f $DISK_IMAGE_PATH ]; then
+	$(dirname "$0")/image-full.sh
+	exit 0
+fi
+
+MOUNT_DIR=/mnt
+
+LOOP_DEV=$(sudo losetup -f --show $DISK_IMAGE_PATH)
+sudo partprobe $LOOP_DEV
+
+ROOT_PARTITON=${LOOP_DEV}p2
+
+sudo mount $ROOT_PARTITON $MOUNT_DIR
+
+sudo rsync -a ${SYSROOT}/* ${MOUNT_DIR}/
+
+sudo umount $MOUNT_DIR
+
+sudo losetup -d $LOOP_DEV

install-usb.sh

@@ -1,8 +0,0 @@
-#!/bin/sh
-set -e
-. ./disk.sh
-
-SIZE=$(stat -c '%s' banan-os.img | numfmt --to=iec)
-
-echo Writing ${SIZE}iB
-sudo dd if=banan-os.img of=/dev/sda status=progress

kernel/.gitignore

@@ -1,3 +0,0 @@
-*.d
-*.kernel
-*.o

kernel/CMakeLists.txt

@@ -0,0 +1,207 @@
+cmake_minimum_required(VERSION 3.26)
+
+project(kernel CXX C ASM)
+
+if("${BANAN_ARCH}" STREQUAL "x86_64")
+	set(ELF_FORMAT elf64-x86-64)
+elseif("${BANAN_ARCH}" STREQUAL "i386")
+	set(ELF_FORMAT elf32-i386)
+endif()
+
+set(KERNEL_SOURCES
+	font/prefs.psf.o
+	kernel/ACPI.cpp
+	kernel/APIC.cpp
+	kernel/CPUID.cpp
+	kernel/Debug.cpp
+	kernel/Device/Device.cpp
+	kernel/Device/NullDevice.cpp
+	kernel/Device/ZeroDevice.cpp
+	kernel/Errors.cpp
+	kernel/Font.cpp
+	kernel/FS/DevFS/FileSystem.cpp
+	kernel/FS/Ext2/FileSystem.cpp
+	kernel/FS/Ext2/Inode.cpp
+	kernel/FS/Inode.cpp
+	kernel/FS/Pipe.cpp
+	kernel/FS/ProcFS/FileSystem.cpp
+	kernel/FS/ProcFS/Inode.cpp
+	kernel/FS/RamFS/FileSystem.cpp
+	kernel/FS/RamFS/Inode.cpp
+	kernel/FS/VirtualFileSystem.cpp
+	kernel/Input/PS2Controller.cpp
+	kernel/Input/PS2Keyboard.cpp
+	kernel/Input/PS2Keymap.cpp
+	kernel/InterruptController.cpp
+	kernel/kernel.cpp
+	kernel/Memory/FileBackedRegion.cpp
+	kernel/Memory/GeneralAllocator.cpp
+	kernel/Memory/Heap.cpp
+	kernel/Memory/kmalloc.cpp
+	kernel/Memory/MemoryBackedRegion.cpp
+	kernel/Memory/MemoryRegion.cpp
+	kernel/Memory/PhysicalRange.cpp
+	kernel/Memory/VirtualRange.cpp
+	kernel/Networking/E1000.cpp
+	kernel/OpenFileDescriptorSet.cpp
+	kernel/Panic.cpp
+	kernel/PCI.cpp
+	kernel/PIC.cpp
+	kernel/Process.cpp
+	kernel/Scheduler.cpp
+	kernel/Semaphore.cpp
+	kernel/SpinLock.cpp
+	kernel/SSP.cpp
+	kernel/Storage/ATABus.cpp
+	kernel/Storage/ATAController.cpp
+	kernel/Storage/ATADevice.cpp
+	kernel/Storage/DiskCache.cpp
+	kernel/Storage/StorageDevice.cpp
+	kernel/Syscall.cpp
+	kernel/Syscall.S
+	kernel/Terminal/Serial.cpp
+	kernel/Terminal/TTY.cpp
+	kernel/Terminal/VesaTerminalDriver.cpp
+	kernel/Terminal/VirtualTTY.cpp
+	kernel/Thread.cpp
+	kernel/Timer/HPET.cpp
+	kernel/Timer/PIT.cpp
+	kernel/Timer/RTC.cpp
+	kernel/Timer/Timer.cpp
+	icxxabi.cpp
+)
+
+#set(ENABLE_KERNEL_UBSAN True)
+
+if(ENABLE_KERNEL_UBSAN)
+	set(KERNEL_SOURCES ${KERNEL_SOURCES} ubsan.cpp)
+endif()
+
+if("${BANAN_ARCH}" STREQUAL "x86_64")
+	set(KERNEL_SOURCES
+		${KERNEL_SOURCES}
+		arch/x86_64/boot.S
+		arch/x86_64/GDT.cpp
+		arch/x86_64/IDT.cpp
+		arch/x86_64/interrupts.S
+		arch/x86_64/PageTable.cpp
+		arch/x86_64/Signal.S
+		arch/x86_64/Thread.S
+	)
+elseif("${BANAN_ARCH}" STREQUAL "i386")
+	set(KERNEL_SOURCES
+		${KERNEL_SOURCES}
+		arch/i386/boot.S
+		arch/i386/GDT.cpp
+		arch/i386/IDT.cpp
+		arch/i386/MMU.cpp
+		arch/i386/SpinLock.S
+		arch/i386/Thread.S
+	)
+else()
+	message(FATAL_ERROR "unsupported architecure ${BANAN_ARCH}")
+endif()
+
+file(GLOB_RECURSE LAI_SOURCES
+	lai/*.c
+)
+set(LAI_SOURCES
+	${LAI_SOURCES}
+	kernel/lai_host.cpp
+)
+
+set(BAN_SOURCES
+	../BAN/BAN/New.cpp
+	../BAN/BAN/String.cpp
+	../BAN/BAN/StringView.cpp
+	../BAN/BAN/Time.cpp
+)
+
+set(LIBC_SOURCES
+	../libc/ctype.cpp
+	../libc/string.cpp
+)
+
+set(LIBELF_SOURCES
+	../LibELF/LibELF/LoadableELF.cpp
+)
+
+set(KERNEL_SOURCES
+	${KERNEL_SOURCES}
+	${LAI_SOURCES}
+	${BAN_SOURCES}
+	${LIBC_SOURCES}
+	${LIBELF_SOURCES}
+)
+
+add_executable(kernel ${KERNEL_SOURCES})
+add_dependencies(kernel headers)
+
+target_compile_definitions(kernel PUBLIC __is_kernel)
+target_compile_definitions(kernel PUBLIC __arch=${BANAN_ARCH})
+
+target_compile_options(kernel PUBLIC -O2 -g)
+target_compile_options(kernel PUBLIC $<$<COMPILE_LANGUAGE:CXX>:-Wno-literal-suffix -fno-rtti -fno-exceptions>)
+target_compile_options(kernel PUBLIC -fmacro-prefix-map=${CMAKE_CURRENT_SOURCE_DIR}=.)
+target_compile_options(kernel PUBLIC -fstack-protector -ffreestanding -Wall -Werror=return-type -Wstack-usage=1024 -fno-omit-frame-pointer -mgeneral-regs-only)
+
+if(ENABLE_KERNEL_UBSAN)
+	target_compile_options(kernel PUBLIC -fsanitize=undefined)
+endif()
+
+if("${BANAN_ARCH}" STREQUAL "x86_64")
+	target_compile_options(kernel PUBLIC -mcmodel=kernel -mno-red-zone -mno-mmx)
+	target_link_options(kernel PUBLIC LINKER:-z,max-page-size=4096)
+	target_link_options(kernel PUBLIC LINKER:-T,${CMAKE_CURRENT_SOURCE_DIR}/arch/x86_64/linker.ld)
+elseif("${BANAN_ARCH}" STREQUAL "i386")
+	target_link_options(kernel PUBLIC LINKER:-T,${CMAKE_CURRENT_SOURCE_DIR}/arch/i386/linker.ld)
+endif()
+
+target_link_options(kernel PUBLIC -ffreestanding -nostdlib)
+
+add_custom_target(crt0
+	COMMAND ${CMAKE_CXX_COMPILER} -c ${CMAKE_CURRENT_SOURCE_DIR}/arch/${BANAN_ARCH}/crt0.S -o ${CMAKE_CURRENT_BINARY_DIR}/crt0.o
+	DEPENDS headers
+)
+
+add_custom_command(
+	TARGET crt0
+	POST_BUILD
+	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/crt0.o ${BANAN_LIB}/
+)
+
+add_custom_target(kernel-headers
+	COMMAND sudo rsync -a ${CMAKE_CURRENT_SOURCE_DIR}/include/ ${BANAN_INCLUDE}/
+	COMMAND sudo rsync -a ${CMAKE_CURRENT_SOURCE_DIR}/lai/include/ ${BANAN_INCLUDE}/
+	DEPENDS sysroot
+	USES_TERMINAL
+)
+
+add_custom_target(kernel-install
+	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/kernel ${BANAN_BOOT}/banan-os.kernel
+	DEPENDS kernel
+	USES_TERMINAL
+)
+
+execute_process(COMMAND ${CMAKE_CXX_COMPILER} -print-file-name=crtbegin.o OUTPUT_VARIABLE CRTBEGIN OUTPUT_STRIP_TRAILING_WHITESPACE)
+execute_process(COMMAND ${CMAKE_CXX_COMPILER} -print-file-name=crtend.o OUTPUT_VARIABLE CRTEND OUTPUT_STRIP_TRAILING_WHITESPACE)
+
+add_custom_command(
+	TARGET kernel PRE_LINK
+	COMMAND ${CMAKE_CXX_COMPILER} -MD -c ${CMAKE_CURRENT_SOURCE_DIR}/arch/${BANAN_ARCH}/crti.S ${COMPILE_OPTIONS}
+	COMMAND ${CMAKE_CXX_COMPILER} -MD -c ${CMAKE_CURRENT_SOURCE_DIR}/arch/${BANAN_ARCH}/crtn.S ${COMPILE_OPTIONS}
+	COMMAND cp ${CRTBEGIN} .
+	COMMAND cp ${CRTEND} .
+)
+
+add_custom_command(
+	TARGET kernel POST_BUILD
+	COMMAND x86_64-banan_os-strip ${CMAKE_CURRENT_BINARY_DIR}/kernel
+)
+
+add_custom_command(
+	OUTPUT font/prefs.psf.o
+	COMMAND cd ${CMAKE_CURRENT_SOURCE_DIR} && objcopy -O ${ELF_FORMAT} -B i386 -I binary font/prefs.psf ${CMAKE_CURRENT_BINARY_DIR}/font/prefs.psf.o
+)
+
+set(CMAKE_CXX_LINK_EXECUTABLE "${CMAKE_CXX_COMPILER} <CMAKE_CXX_LINK_FLAGS> <FLAGS> <LINK_FLAGS> -o <TARGET> ${CMAKE_CURRENT_BINARY_DIR}/crti.o ${CMAKE_CURRENT_BINARY_DIR}/crtbegin.o <OBJECTS> ${CMAKE_CURRENT_BINARY_DIR}/crtend.o ${CMAKE_CURRENT_BINARY_DIR}/crtn.o -lgcc ")

kernel/Makefile

@@ -1,131 +0,0 @@
-DEFAULT_HOST!=../default-host.sh
-HOST?=DEFAULT_HOST
-HOSTARCH!=../target-triplet-to-arch.sh $(HOST)
- 
-CFLAGS?=-O2 -g
-CPPFLAGS?=
-LDFLAGS?=
-LIBS?=
- 
-DESTDIR?=
-PREFIX?=/usr/local
-EXEC_PREFIX?=$(PREFIX)
-BOOTDIR?=$(EXEC_PREFIX)/boot
-INCLUDEDIR?=$(PREFIX)/include
- 
-CFLAGS:=$(CFLAGS) -D__is_kernel -D__arch=$(HOSTARCH) -Iinclude -fstack-protector -ffreestanding -Wall -Wextra -Werror=return-type -fno-omit-frame-pointer -mno-sse -mno-sse2
-CPPFLAGS:=$(CPPFLAGS) -fno-rtti -fno-exceptions
-LDFLAGS:=$(LDFLAGS)
-LIBS:=$(LIBS) -nostdlib -lk -lbank -lgcc
- 
-ARCHDIR=arch/$(HOSTARCH)
- 
-include $(ARCHDIR)/make.config
- 
-CFLAGS:=$(CFLAGS) $(KERNEL_ARCH_CFLAGS)
-CPPFLAGS:=$(CPPFLAGS) $(KERNEL_ARCH_CPPFLAGS)
-LDFLAGS:=$(LDFLAGS) $(KERNEL_ARCH_LDFLAGS)
-LIBS:=$(LIBS) $(KERNEL_ARCH_LIBS)
- 
-ifeq ($(UBSAN), 1)
-CFLAGS:=$(CFLAGS) -fsanitize=undefined
-endif
- 
-BUILDDIR=$(abspath build)
- 
-KERNEL_OBJS=					\
-$(KERNEL_ARCH_OBJS)				\
-font/prefs.o					\
-kernel/APIC.o					\
-kernel/build_libc.o				\
-kernel/CPUID.o					\
-kernel/Debug.o					\
-kernel/Font.o					\
-kernel/FS/Ext2.o				\
-kernel/FS/VirtualFileSystem.o	\
-kernel/Input.o					\
-kernel/InterruptController.o	\
-kernel/kernel.o					\
-kernel/kmalloc.o				\
-kernel/PCI.o					\
-kernel/PIC.o					\
-kernel/PIT.o					\
-kernel/Process.o				\
-kernel/RTC.o					\
-kernel/Scheduler.o				\
-kernel/Serial.o					\
-kernel/Shell.o					\
-kernel/SpinLock.o				\
-kernel/SSP.o					\
-kernel/Storage/ATAController.o	\
-kernel/Storage/StorageDevice.o	\
-kernel/Syscall.o				\
-kernel/Thread.o					\
-kernel/TTY.o					\
-kernel/VesaTerminalDriver.o		\
-userspace/userspace.o			\
-icxxabi.o						\
-ubsan.o							\
- 
-OBJS=					\
-$(ARCHDIR)/crti.o		\
-$(ARCHDIR)/crtbegin.o	\
-$(KERNEL_OBJS)			\
-$(ARCHDIR)/crtend.o		\
-$(ARCHDIR)/crtn.o		\
- 
-LINK_LIST=				\
-$(LDFLAGS)				\
-$(ARCHDIR)/crti.o		\
-$(ARCHDIR)/crtbegin.o	\
-$(KERNEL_OBJS)			\
-$(LIBS)					\
-$(ARCHDIR)/crtend.o		\
-$(ARCHDIR)/crtn.o		\
- 
-.PHONY: all always clean install install-headers install-kernel
-.SUFFIXES: .o .c .cpp .S .psf
- 
-all: banan-os.kernel
- 
-banan-os.kernel: always $(OBJS) $(ARCHDIR)/linker.ld
-	cd $(BUILDDIR) && $(CXX) -T ../$(ARCHDIR)/linker.ld -o banan-os.kernel $(CFLAGS) $(CPPFLAGS) $(LINK_LIST)
-	cd $(BUILDDIR) && grub-file --is-x86-multiboot banan-os.kernel
- 
-$(ARCHDIR)/crtbegin.o $(ARCHDIR)/crtend.o:
-	OBJ=`$(CC) $(CFLAGS) $(LDFLAGS) -print-file-name=$(@F)` && cp "$$OBJ" $(BUILDDIR)/$@
- 
-.c.o:
-	$(CC) -MD -c $< -o $(BUILDDIR)/$@ $(CFLAGS)
- 
-.cpp.o:
-	$(CXX) -MD -c $< -o $(BUILDDIR)/$@ $(CFLAGS) $(CPPFLAGS)
- 
-.S.o:
-	$(CC) -MD -c $< -o $(BUILDDIR)/$@ $(CFLAGS)
- 
-.psf.o:
-	objcopy -O $(ELF_FORMAT) -B i386 -I binary $< $(BUILDDIR)/$@
-
-always:
-	mkdir -p $(BUILDDIR)/$(ARCHDIR)
-	mkdir -p $(BUILDDIR)/kernel
-	mkdir -p $(BUILDDIR)/kernel/FS
-	mkdir -p $(BUILDDIR)/kernel/Storage
-	mkdir -p $(BUILDDIR)/userspace
-	mkdir -p $(BUILDDIR)/font
-
-clean:
-	rm -rf $(BUILDDIR)
-
-install: install-headers install-kernel
- 
-install-headers:
-	mkdir -p $(DESTDIR)$(INCLUDEDIR)
-	cp -R --preserve=timestamps include/. $(DESTDIR)$(INCLUDEDIR)/.
- 
-install-kernel: banan-os.kernel
-	mkdir -p $(DESTDIR)$(BOOTDIR)
-	cp $(BUILDDIR)/banan-os.kernel $(DESTDIR)$(BOOTDIR)
- 
--include $(OBJS:.o=.d)

kernel/arch/i386/GDT.cpp

@@ -109,6 +109,11 @@ namespace Kernel::GDT
 		write_entry(offset, (uint32_t)s_tss, sizeof(TaskStateSegment), 0x89, 0x0);
 	}
 
+	void set_tss_stack(uintptr_t esp)
+	{
+		s_tss->esp0 = esp;
+	}
+
 	static void flush_gdt()
 	{
 		asm volatile("lgdt %0" :: "m"(s_gdtr));

kernel/arch/i386/IDT.cpp

@@ -1,8 +1,9 @@
 #include <BAN/Errors.h>
 #include <kernel/IDT.h>
 #include <kernel/InterruptController.h>
-#include <kernel/kmalloc.h>
+#include <kernel/Memory/kmalloc.h>
 #include <kernel/Panic.h>
+#include <kernel/Scheduler.h>
 
 #define INTERRUPT_HANDLER____(i, msg)													\
 	static void interrupt ## i ()														\
@@ -132,6 +133,8 @@ found:
 		// NOTE: Scheduler sends PIT eoi's
 		if (irq != PIT_IRQ)
 			InterruptController::get().eoi(irq);
+
+		Kernel::Scheduler::get().reschedule_if_idling();
 	}
 
 	extern "C" void handle_irq_common();
@@ -151,7 +154,7 @@ found:
 		"popa;"
 		"iret;"
 	);
-	
+
 	extern "C" void syscall_asm();
 	asm(
 	".global syscall_asm;"
@@ -171,7 +174,18 @@ found:
 		"addl $16, %esp;"
 		"popw %es;"
 		"popw %ds;"
-		"popa;"
+		
+		// NOTE: following instructions are same as in 'popa', except we skip eax
+		//       since it holds the return value of the syscall.
+		"popl %edi;"
+		"popl %esi;"
+		"popl %ebp;"
+		"addl $4, %esp;"
+		"popl %ebx;"
+		"popl %edx;"
+		"popl %ecx;"
+		"addl $4, %esp;"
+		
 		"iret;"
 	);
 

kernel/arch/i386/MMU.cpp

@@ -1,136 +1,227 @@
 #include <BAN/Errors.h>
 #include <kernel/Debug.h>
-#include <kernel/MMU.h>
-#include <kernel/kmalloc.h>
+#include <kernel/Memory/MMU.h>
+#include <kernel/Memory/kmalloc.h>
 
 #include <string.h>
 
 #define MMU_DEBUG_PRINT 0
 
 // bits 31-12 set
-#define PAGE_MASK 0xfffff000
-#define PAGE_SIZE 0x00001000
+#define PAGE_MASK  0xfffff000
+#define FLAGS_MASK 0x00000fff
 
-static MMU* s_instance = nullptr;
-
-void MMU::intialize()
+namespace Kernel
 {
-	ASSERT(s_instance == nullptr);
-	s_instance = new MMU();
-}
 
-MMU& MMU::get()
-{
-	ASSERT(s_instance);
-	return *s_instance;
-}
+	static MMU* s_instance = nullptr;
 
-static uint64_t* allocate_page_aligned_page()
-{
-	uint64_t* page = (uint64_t*)kmalloc(PAGE_SIZE, PAGE_SIZE);
-	ASSERT(page);
-	ASSERT(((uintptr_t)page % PAGE_SIZE) == 0);
-	memset(page, 0, PAGE_SIZE);
-	return page;
-}
-
-MMU::MMU()
-{
-	m_highest_paging_struct = (uint64_t*)kmalloc(sizeof(uint64_t) * 4, 32);
-	ASSERT(m_highest_paging_struct);
-	ASSERT(((uintptr_t)m_highest_paging_struct % 32) == 0);
-
-	// allocate all page directories
-	for (int i = 0; i < 4; i++)
+	void MMU::initialize()
 	{
-		uint64_t* page_directory = allocate_page_aligned_page();
-		m_highest_paging_struct[i] = (uint64_t)page_directory | Flags::Present;
+		ASSERT(s_instance == nullptr);
+		s_instance = new MMU();
+		ASSERT(s_instance);
+		s_instance->initialize_kernel();
+		s_instance->load();
 	}
 
-	// create and identity map first 6 MiB
-	uint64_t* page_directory1 = (uint64_t*)(m_highest_paging_struct[0] & PAGE_MASK);
-	for (uint64_t i = 0; i < 3; i++)
+	MMU& MMU::get()
 	{
-		uint64_t* page_table = allocate_page_aligned_page();
-		for (uint64_t j = 0; j < 512; j++)
-			page_table[j] = (i << 21) | (j << 12) | Flags::ReadWrite | Flags::Present;
-
-		page_directory1[i] = (uint64_t)page_table | Flags::ReadWrite | Flags::Present;
+		ASSERT(s_instance);
+		return *s_instance;
 	}
 
-	// dont map first page (0 -> 4 KiB) so that nullptr dereference
-	// causes page fault :)
-	uint64_t* page_table1 = (uint64_t*)(page_directory1[0] & PAGE_MASK);
-	page_table1[0] = 0;
-
-	// reload this new pdpt
-	asm volatile("movl %0, %%cr3" :: "r"(m_highest_paging_struct));
-}
-
-void MMU::allocate_page(uintptr_t address, uint8_t flags)
-{
-#if MMU_DEBUG_PRINT
-	dprintln("AllocatePage(0x{8H})", address);
-#endif
-	ASSERT(flags & Flags::Present);
-
-	address &= PAGE_MASK;
-
-	uint32_t pdpte = (address & 0xC0000000) >> 30;
-	uint32_t pde   = (address & 0x3FE00000) >> 21;
-	uint32_t pte   = (address & 0x001FF000) >> 12;
-
-	uint64_t* page_directory = (uint64_t*)(m_highest_paging_struct[pdpte] & PAGE_MASK);
-	if (!(page_directory[pde] & Flags::Present))
+	static uint64_t* allocate_page_aligned_page()
 	{
-		uint64_t* page_table = allocate_page_aligned_page();
-		page_directory[pde] = (uint64_t)page_table;
+		uint64_t* page = (uint64_t*)kmalloc(PAGE_SIZE, PAGE_SIZE);
+		ASSERT(page);
+		ASSERT(((uintptr_t)page % PAGE_SIZE) == 0);
+		memset(page, 0, PAGE_SIZE);
+		return page;
 	}
-	page_directory[pde] |= flags;
 
-	uint64_t* page_table = (uint64_t*)(page_directory[pde] & PAGE_MASK);
-	page_table[pte] = address | flags;
+	void MMU::initialize_kernel()
+	{
+		m_highest_paging_struct = (uint64_t*)kmalloc(sizeof(uint64_t) * 4, 32);
+		ASSERT(m_highest_paging_struct);
+		ASSERT(((uintptr_t)m_highest_paging_struct % 32) == 0);
+
+		// allocate all page directories
+		for (int i = 0; i < 4; i++)
+		{
+			uint64_t* page_directory = allocate_page_aligned_page();
+			m_highest_paging_struct[i] = (uint64_t)page_directory | Flags::Present;
+		}
+
+		// FIXME: We should just identity map until g_kernel_end
+
+		// create and identity map first 6 MiB
+		uint64_t* page_directory1 = (uint64_t*)(m_highest_paging_struct[0] & PAGE_MASK);
+		for (uint64_t i = 0; i < 3; i++)
+		{
+			uint64_t* page_table = allocate_page_aligned_page();
+			for (uint64_t j = 0; j < 512; j++)
+				page_table[j] = (i << 21) | (j << 12) | Flags::ReadWrite | Flags::Present;
+
+			page_directory1[i] = (uint64_t)page_table | Flags::ReadWrite | Flags::Present;
+		}
+
+		// dont map first page (0 -> 4 KiB) so that nullptr dereference
+		// causes page fault :)
+		uint64_t* page_table1 = (uint64_t*)(page_directory1[0] & PAGE_MASK);
+		page_table1[0] = 0;
+	}
+
+	MMU::MMU()
+	{
+		if (s_instance == nullptr)
+			return;
+		
+		// Here we copy the s_instances paging structs since they are
+		// global for every process
+
+		uint64_t* global_pdpt = s_instance->m_highest_paging_struct;
+
+		uint64_t* pdpt = (uint64_t*)kmalloc(sizeof(uint64_t) * 4, 32);
+		ASSERT(pdpt);
+		
+		for (uint32_t pdpte = 0; pdpte < 4; pdpte++)
+		{
+			if (!(global_pdpt[pdpte] & Flags::Present))
+				continue;
+
+			uint64_t* global_pd = (uint64_t*)(global_pdpt[pdpte] & PAGE_MASK);
+
+			uint64_t* pd = allocate_page_aligned_page();
+			pdpt[pdpte] = (uint64_t)pd | (global_pdpt[pdpte] & ~PAGE_MASK);
+
+			for (uint32_t pde = 0; pde < 512; pde++)
+			{
+				if (!(global_pd[pde] & Flags::Present))
+					continue;
+
+				uint64_t* global_pt = (uint64_t*)(global_pd[pde] & PAGE_MASK);
+
+				uint64_t* pt = allocate_page_aligned_page();
+				pd[pde] = (uint64_t)pt | (global_pd[pde] & ~PAGE_MASK);
+
+				memcpy(pt, global_pt, PAGE_SIZE);
+			}
+		}
+
+		m_highest_paging_struct = pdpt;
+	}
+
+	MMU::~MMU()
+	{
+		uint64_t* pdpt = m_highest_paging_struct;
+		for (uint32_t pdpte = 0; pdpte < 512; pdpte++)
+		{
+			if (!(pdpt[pdpte] & Flags::Present))
+				continue;
+			uint64_t* pd = (uint64_t*)(pdpt[pdpte] & PAGE_MASK);
+			for (uint32_t pde = 0; pde < 512; pde++)
+			{
+				if (!(pd[pde] & Flags::Present))
+					continue;
+				kfree((void*)(pd[pde] & PAGE_MASK));
+			}
+			kfree(pd);
+		}
+		kfree(pdpt);
+	}
+
+	void MMU::load()
+	{
+		asm volatile("movl %0, %%cr3" :: "r"(m_highest_paging_struct));
+	}
+
+	void MMU::map_page_at(paddr_t paddr, vaddr_t vaddr, uint8_t flags)
+	{
+	#if MMU_DEBUG_PRINT
+		dprintln("AllocatePage(0x{8H})", address);
+	#endif
+		ASSERT(flags & Flags::Present);
+
+		ASSERT(!(paddr & ~PAGE_MASK));
+		ASSERT(!(vaddr & ~PAGE_MASK));
+
+		uint32_t pdpte = (vaddr & 0xC0000000) >> 30;
+		uint32_t pde   = (vaddr & 0x3FE00000) >> 21;
+		uint32_t pte   = (vaddr & 0x001FF000) >> 12;
+
+		uint64_t* page_directory = (uint64_t*)(m_highest_paging_struct[pdpte] & PAGE_MASK);
+		if (!(page_directory[pde] & Flags::Present))
+		{
+			uint64_t* page_table = allocate_page_aligned_page();
+			page_directory[pde] = (uint64_t)page_table;
+		}
+		page_directory[pde] |= flags;
+
+		uint64_t* page_table = (uint64_t*)(page_directory[pde] & PAGE_MASK);
+		page_table[pte] = paddr | flags;
+	}
+
+	void MMU::identity_map_page(paddr_t address, uint8_t flags)
+	{
+		address &= PAGE_MASK;
+		map_page_at(address, address, flags);
+	}
+
+	void MMU::identity_map_range(paddr_t address, ptrdiff_t size, uint8_t flags)
+	{
+		paddr_t s_page = address & PAGE_MASK;
+		paddr_t e_page = (address + size - 1) & PAGE_MASK;
+		for (paddr_t page = s_page; page <= e_page; page += PAGE_SIZE)
+			identity_map_page(page, flags);
+	}
+
+	void MMU::unmap_page(vaddr_t address)
+	{
+	#if MMU_DEBUG_PRINT
+		dprintln("UnAllocatePage(0x{8H})", address & PAGE_MASK);
+	#endif
+
+		uint32_t pdpte = (address & 0xC0000000) >> 30;
+		uint32_t pde   = (address & 0x3FE00000) >> 21;
+		uint32_t pte   = (address & 0x001FF000) >> 12;
+
+		uint64_t* page_directory = (uint64_t*)(m_highest_paging_struct[pdpte] & PAGE_MASK);
+		if (!(page_directory[pde] & Flags::Present))
+			return;
+
+		uint64_t* page_table = (uint64_t*)(page_directory[pde] & PAGE_MASK);
+		if (!(page_table[pte] & Flags::Present))
+			return;
+
+		page_table[pte] = 0;
+
+		// TODO: Unallocate the page table if this was the only allocated page
+	}
+
+	void MMU::unmap_range(vaddr_t address, ptrdiff_t size)
+	{
+		uintptr_t s_page = address & PAGE_MASK;
+		uintptr_t e_page = (address + size - 1) & PAGE_MASK;
+		for (uintptr_t page = s_page; page <= e_page; page += PAGE_SIZE)
+			unmap_page(page);
+	}
+
+	uint8_t MMU::get_page_flags(vaddr_t address) const
+	{
+		uint32_t pdpte = (address & 0xC0000000) >> 30;
+		uint32_t pde   = (address & 0x3FE00000) >> 21;
+		uint32_t pte   = (address & 0x001FF000) >> 12;
+
+		uint64_t* page_directory = (uint64_t*)(m_highest_paging_struct[pdpte] & PAGE_MASK);
+		if (!(page_directory[pde] & Flags::Present))
+			return 0;
+
+		uint64_t* page_table = (uint64_t*)(page_directory[pde] & PAGE_MASK);
+		if (!(page_table[pte] & Flags::Present))
+			return 0;
+
+		return page_table[pte] & FLAGS_MASK;
+	}
 
-	asm volatile("invlpg (%0)" :: "r"(address) : "memory");
-}
-
-void MMU::allocate_range(uintptr_t address, ptrdiff_t size, uint8_t flags)
-{
-	uintptr_t s_page = address & PAGE_MASK;
-	uintptr_t e_page = (address + size - 1) & PAGE_MASK;
-	for (uintptr_t page = s_page; page <= e_page; page += PAGE_SIZE)
-		allocate_page(page, flags);
-}
-
-void MMU::unallocate_page(uintptr_t address)
-{
-#if MMU_DEBUG_PRINT
-	dprintln("UnAllocatePage(0x{8H})", address & PAGE_MASK);
-#endif
-
-	uint32_t pdpte = (address & 0xC0000000) >> 30;
-	uint32_t pde   = (address & 0x3FE00000) >> 21;
-	uint32_t pte   = (address & 0x001FF000) >> 12;
-
-	uint64_t* page_directory = (uint64_t*)(m_highest_paging_struct[pdpte] & PAGE_MASK);
-	if (!(page_directory[pde] & Flags::Present))
-		return;
-
-	uint64_t* page_table = (uint64_t*)(page_directory[pde] & PAGE_MASK);
-	if (!(page_table[pte] & Flags::Present))
-		return;
-
-	page_table[pte] = 0;
-
-	// TODO: Unallocate the page table if this was the only allocated page
-
-	asm volatile("invlpg (%0)" :: "r"(address & PAGE_MASK) : "memory");
-}
-
-void MMU::unallocate_range(uintptr_t address, ptrdiff_t size)
-{
-	uintptr_t s_page = address & PAGE_MASK;
-	uintptr_t e_page = (address + size - 1) & PAGE_MASK;
-	for (uintptr_t page = s_page; page <= e_page; page += PAGE_SIZE)
-		unallocate_page(page);
 }

kernel/arch/i386/Thread.S

@@ -25,4 +25,23 @@ continue_thread:
 	movl 8(%esp), %ecx
 	movl 4(%esp), %esp
 	movl $0, %eax
-	jmp *%ecx
+	jmp *%ecx
+
+# void thread_jump_userspace(uint32_t rsp, uint32_t rip)
+.global thread_jump_userspace
+thread_jump_userspace:
+	movl $0x23, %eax
+	movw %ax, %ds
+	movw %ax, %es
+	movw %ax, %fs
+	movw %ax, %gs
+
+	movl 8(%esp), %ecx
+	movl 4(%esp), %esp
+
+	pushl $0x23
+	pushl %esp
+	pushfl
+	pushl $0x1B
+	pushl %ecx
+	iret

kernel/arch/i386/boot.S

@@ -28,9 +28,7 @@ g_boot_stack_bottom:
 g_boot_stack_top:
 
 # 0 MiB -> 1 MiB: bootloader stuff
-# 1 MiB -> 2 MiB: kernel
-# 2 MiB -> 3 MiB: kmalloc
-# 3 MiB -> 4 Mib: kmalloc_fixed
+# 1 MiB ->      : kernel
 .align 32
 boot_page_directory_pointer_table:
 	.skip 4 * 8

kernel/arch/i386/crt0.S

@@ -0,0 +1,23 @@
+.section .text
+
+.global _start
+_start:
+	# Set up end of the stack frame linked list.
+	movl $0, %ebp
+	pushl %ebp # rip=0
+	pushl %ebp # rbp=0
+	movl %esp, %ebp
+
+	# Prepare signals, memory allocation, stdio and such.
+	#call initialize_standard_library
+
+	# Run the global constructors.
+	call _init
+
+	# Run main
+	call main
+
+	# Terminate the process with the exit code.
+	movl %eax, %edi
+	call exit
+.size _start, . - _start

kernel/arch/i386/linker.ld

@@ -4,6 +4,7 @@ SECTIONS
 {
 	. = 0x00100000;
 
+	g_kernel_start = .;
 	.text BLOCK(4K) : ALIGN(4K)
 	{
 		*(.multiboot)
@@ -11,9 +12,7 @@ SECTIONS
 	}
 	.rodata BLOCK(4K) : ALIGN(4K)
 	{
-		g_rodata_start = .;
 		*(.rodata.*)
-		g_rodata_end = .;
 	}
 	.data BLOCK(4K) : ALIGN(4K)
 	{
@@ -26,13 +25,4 @@ SECTIONS
 	}
 
 	g_kernel_end = .;
-
-	. = 0x00A00000;
-
-	g_userspace_start = .;
-	.userspace BLOCK(4K) : ALIGN(4K)
-	{
-		*(.userspace)
-	}
-	g_userspace_end = .;
 }

kernel/arch/i386/make.config

@@ -1,15 +0,0 @@
-KERNEL_ARCH_CFLAGS=
-KERNEL_ARCH_CPPFLAGS=
-KERNEL_ARCH_LDFLAGS=
-KERNEL_ARCH_LIBS=
- 
-ELF_FORMAT=elf32-i386
-
-KERNEL_ARCH_OBJS=		\
-$(ARCHDIR)/boot.o		\
-$(ARCHDIR)/GDT.o		\
-$(ARCHDIR)/IDT.o		\
-$(ARCHDIR)/MMU.o		\
-$(ARCHDIR)/SpinLock.o	\
-$(ARCHDIR)/Thread.o		\
- 

kernel/arch/x86_64/GDT.cpp

@@ -54,6 +54,8 @@ namespace Kernel::GDT
 		uint64_t address;
 	} __attribute__((packed));
 
+	static constexpr uint16_t s_tss_offset = 0x28;
+
 	static TaskStateSegment* s_tss = nullptr;
 	static SegmentDescriptor* s_gdt = nullptr;
 	static GDTR s_gdtr;
@@ -73,30 +75,35 @@ namespace Kernel::GDT
 		desc.flags = flags;
 	}
 
-	static void write_tss(uint8_t offset)
+	static void write_tss()
 	{
 		s_tss = new TaskStateSegment();
 		ASSERT(s_tss);
 		
 		memset(s_tss, 0x00, sizeof(TaskStateSegment));
-		s_tss->rsp0 = (uintptr_t)g_boot_stack_top;
+		s_tss->rsp0 = 0;
 		
 		uintptr_t base = (uintptr_t)s_tss;
 
-		write_entry(offset, (uint32_t)base, sizeof(TaskStateSegment), 0x89, 0x0);
-		SegmentDescriptor& desc = *(SegmentDescriptor*)((uintptr_t)s_gdt + offset + 0x08);
+		write_entry(s_tss_offset, (uint32_t)base, sizeof(TaskStateSegment), 0x89, 0x0);
+		SegmentDescriptor& desc = *(SegmentDescriptor*)((uintptr_t)s_gdt + s_tss_offset + 0x08);
 		desc.low = base >> 32;
 		desc.high = 0;
 	}
 
+	void set_tss_stack(uintptr_t rsp)
+	{
+		s_tss->rsp0 = rsp;
+	}
+
 	static void flush_gdt()
 	{
 		asm volatile("lgdt %0" :: "m"(s_gdtr));
 	}
 
-	extern "C" void flush_tss(uint16_t offset)
+	static void flush_tss()
 	{
-		asm volatile("ltr %0" :: "m"(offset));
+		asm volatile("ltr %0" :: "m"(s_tss_offset));
 	}
 
 	void initialize()
@@ -113,10 +120,10 @@ namespace Kernel::GDT
 		write_entry(0x10, 0x00000000, 0xFFFFF, 0x92, 0xC); // kernel data
 		write_entry(0x18, 0x00000000, 0xFFFFF, 0xFA, 0xA); // user code
 		write_entry(0x20, 0x00000000, 0xFFFFF, 0xF2, 0xC); // user data
-		write_tss(0x28);
+		write_tss();
 
 		flush_gdt();
-		flush_tss(0x28);
+		flush_tss();
 	}
 
 }

kernel/arch/x86_64/IDT.cpp

@@ -1,8 +1,14 @@
 #include <BAN/Errors.h>
 #include <kernel/IDT.h>
 #include <kernel/InterruptController.h>
-#include <kernel/kmalloc.h>
+#include <kernel/InterruptStack.h>
+#include <kernel/Memory/kmalloc.h>
 #include <kernel/Panic.h>
+#include <kernel/Process.h>
+#include <kernel/Scheduler.h>
+#include <kernel/Timer/PIT.h>
+
+#include <unistd.h>
 
 #define REGISTER_ISR_HANDLER(i) register_interrupt_handler(i, isr ## i)
 #define REGISTER_IRQ_HANDLER(i) register_interrupt_handler(IRQ_VECTOR_BASE + i, irq ## i)
@@ -59,6 +65,65 @@ namespace IDT
 
 	static void(*s_irq_handlers[0x10])() { nullptr };
 
+	enum ISR
+	{
+		DivisionError,
+		Debug,
+		NonMaskableInterrupt,
+		Breakpoint,
+		Overflow,
+		BoundRangeException,
+		InvalidOpcode,
+		DeviceNotAvailable,
+		DoubleFault,
+		CoprocessorSegmentOverrun,
+		InvalidTSS,
+		SegmentNotPresent,
+		StackSegmentFault,
+		GeneralProtectionFault,
+		PageFault,
+		UnknownException0x0F,
+		x87FloatingPointException,
+		AlignmentCheck,
+		MachineCheck,
+		SIMDFloatingPointException,
+		VirtualizationException,
+		ControlProtectionException,
+		UnknownException0x16,
+		UnknownException0x17,
+		UnknownException0x18,
+		UnknownException0x19,
+		UnknownException0x1A,
+		UnknownException0x1B,
+		HypervisorInjectionException,
+		VMMCommunicationException,
+		SecurityException,
+		UnkownException0x1F,
+	};
+
+	struct PageFaultError
+	{
+		union
+		{
+			uint32_t raw;
+			struct
+			{
+				uint32_t present		: 1;
+				uint32_t write			: 1;
+				uint32_t userspace		: 1;
+				uint32_t reserved_write	: 1;
+				uint32_t instruction	: 1;
+				uint32_t protection_key	: 1;
+				uint32_t shadow_stack	: 1;
+				uint32_t reserved1		: 8;
+				uint32_t sgx_violation	: 1;
+				uint32_t reserved2		: 16;
+			};
+		};
+		
+	};
+	static_assert(sizeof(PageFaultError) == 4);
+
 	static const char* isr_exceptions[] =
 	{
 		"Division Error",
@@ -95,40 +160,170 @@ namespace IDT
 		"Unkown Exception 0x1F",
 	};
 
-	extern "C" void cpp_isr_handler(uint64_t isr, uint64_t error, const Registers* regs)
+	extern "C" void cpp_isr_handler(uint64_t isr, uint64_t error, Kernel::InterruptStack& interrupt_stack, const Registers* regs)
 	{
-		Kernel::panic(
-			"{} (error code: 0x{16H})\r\n"
+#if __enable_sse
+		bool from_userspace = (interrupt_stack.cs & 0b11) == 0b11;
+		if (from_userspace)
+			Kernel::Thread::current().save_sse();
+#endif
+
+		pid_t tid = Kernel::Scheduler::current_tid();
+		pid_t pid = tid ? Kernel::Process::current().pid() : 0;
+
+		if (pid && isr == ISR::PageFault)
+		{
+			PageFaultError page_fault_error;
+			page_fault_error.raw = error;
+
+			// Try demand paging on non present pages
+			if (!page_fault_error.present)
+			{
+				asm volatile("sti");
+				auto result = Kernel::Process::current().allocate_page_for_demand_paging(regs->cr2);
+				asm volatile("cli");
+
+				if (!result.is_error() && result.value())
+					return;
+
+				if (result.is_error())
+				{
+					dwarnln("Demand paging: {}", result.error());
+					Kernel::Thread::current().handle_signal(SIGTERM);
+				}
+			}
+		}
+
+		if (tid)
+		{
+			auto start = Kernel::Thread::current().stack_base();
+			auto end = start + Kernel::Thread::current().stack_size();
+			if (interrupt_stack.rsp < start)
+				derrorln("Stack overflow");
+			if (interrupt_stack.rsp >= end)
+				derrorln("Stack underflow");
+		}
+
+		if (Kernel::PageTable::current().get_page_flags(interrupt_stack.rip & PAGE_ADDR_MASK) & Kernel::PageTable::Flags::Present)
+		{
+			uint8_t* machine_code = (uint8_t*)interrupt_stack.rip;
+			dwarnln("While executing: {2H}{2H}{2H}{2H}{2H}{2H}{2H}{2H}",
+				machine_code[0],
+				machine_code[1],
+				machine_code[2],
+				machine_code[3],
+				machine_code[4],
+				machine_code[5],
+				machine_code[6],
+				machine_code[7]
+			);
+		}
+
+		dwarnln(
+			"{} (error code: 0x{16H}), pid {}, tid {}\r\n"
 			"Register dump\r\n"
 			"rax=0x{16H}, rbx=0x{16H}, rcx=0x{16H}, rdx=0x{16H}\r\n"
 			"rsp=0x{16H}, rbp=0x{16H}, rdi=0x{16H}, rsi=0x{16H}\r\n"
 			"rip=0x{16H}, rflags=0x{16H}\r\n"
-			"cr0=0x{16H}, cr2=0x{16H}, cr3=0x{16H}, cr4=0x{16H}\r\n",
-			isr_exceptions[isr], error,
+			"cr0=0x{16H}, cr2=0x{16H}, cr3=0x{16H}, cr4=0x{16H}",
+			isr_exceptions[isr], error, pid, tid,
 			regs->rax, regs->rbx, regs->rcx, regs->rdx,
 			regs->rsp, regs->rbp, regs->rdi, regs->rsi,
 			regs->rip, regs->rflags,
 			regs->cr0, regs->cr2, regs->cr3, regs->cr4
 		);
-	}
+		if (isr == ISR::PageFault)
+			Kernel::PageTable::current().debug_dump();
+		Debug::dump_stack_trace();
 
-	extern "C" void cpp_irq_handler(uint64_t irq)
-	{
-		if (s_irq_handlers[irq])
-			s_irq_handlers[irq]();
-		else
+		if (tid)
 		{
-			if (!InterruptController::get().is_in_service(irq))
-			{
-				dprintln("spurious irq 0x{2H}", irq);
-				return;
-			}
-			dprintln("no handler for irq 0x{2H}\n", irq);
+			Kernel::Thread::current().set_return_rsp(interrupt_stack.rsp);
+			Kernel::Thread::current().set_return_rip(interrupt_stack.rip);
 		}
 
-		// NOTE: Scheduler sends PIT eoi's
-		if (irq != PIT_IRQ)
+		if (tid && Kernel::Thread::current().is_userspace())
+		{
+			// TODO: Confirm and fix the exception to signal mappings
+
+			int signal = 0;
+			switch (isr)
+			{
+			case ISR::DeviceNotAvailable:
+			case ISR::DivisionError:
+			case ISR::SIMDFloatingPointException:
+			case ISR::x87FloatingPointException:
+				signal = SIGFPE;
+				break;
+			case ISR::AlignmentCheck:
+				signal = SIGBUS;
+				break;
+			case ISR::InvalidOpcode:
+				signal = SIGILL;
+				break;
+			case ISR::PageFault:
+				signal = SIGSEGV;
+				break;			
+			default:
+				dwarnln("Unhandled exception");
+				signal = SIGABRT;
+				break;
+			}
+
+			Kernel::Thread::current().handle_signal(signal);
+		}
+		else
+		{
+			Kernel::panic("Unhandled exception");
+		}
+
+		ASSERT(Kernel::Thread::current().state() != Kernel::Thread::State::Terminated);
+
+#if __enable_sse
+		if (from_userspace)
+		{
+			ASSERT(Kernel::Thread::current().state() == Kernel::Thread::State::Executing);
+			Kernel::Thread::current().load_sse();
+		}
+#endif
+	}
+
+	extern "C" void cpp_irq_handler(uint64_t irq, Kernel::InterruptStack& interrupt_stack)
+	{
+#if __enable_sse
+		bool from_userspace = (interrupt_stack.cs & 0b11) == 0b11;
+		if (from_userspace)
+			Kernel::Thread::current().save_sse();
+#endif
+
+		if (Kernel::Scheduler::current_tid())
+		{
+			Kernel::Thread::current().set_return_rsp(interrupt_stack.rsp);
+			Kernel::Thread::current().set_return_rip(interrupt_stack.rip);
+		}
+
+		if (!InterruptController::get().is_in_service(irq))
+			dprintln("spurious irq 0x{2H}", irq);
+		else
+		{
 			InterruptController::get().eoi(irq);
+			if (s_irq_handlers[irq])
+				s_irq_handlers[irq]();
+			else
+				dprintln("no handler for irq 0x{2H}\n", irq);
+		}
+
+		Kernel::Scheduler::get().reschedule_if_idling();
+
+		ASSERT(Kernel::Thread::current().state() != Kernel::Thread::State::Terminated);
+
+#if __enable_sse
+		if (from_userspace)
+		{
+			ASSERT(Kernel::Thread::current().state() == Kernel::Thread::State::Executing);
+			Kernel::Thread::current().load_sse();
+		}
+#endif
 	}
 
 	static void flush_idt()
@@ -275,4 +470,14 @@ namespace IDT
 		flush_idt();
 	}
 
+	[[noreturn]] void force_triple_fault()
+	{
+		// load 0 sized IDT and trigger an interrupt to force triple fault
+		asm volatile("cli");
+		s_idtr.size = 0;
+		flush_idt();
+		asm volatile("int $0x00");
+		ASSERT_NOT_REACHED();
+	}
+
 }

kernel/arch/x86_64/MMU.cpp

@@ -1,195 +0,0 @@
-#include <BAN/Errors.h>
-#include <kernel/kmalloc.h>
-#include <kernel/MMU.h>
-
-#define PAGE_SIZE 0x1000
-#define PAGE_MASK ~(PAGE_SIZE - 1)
-
-#define CLEANUP_STRUCTURE(s)			\
-	for (uint64_t i = 0; i < 512; i++)	\
-		if (s[i] & Flags::Present)		\
-			goto cleanup_done;			\
-	kfree(s)
-
-static MMU* s_instance = nullptr;
-
-void MMU::intialize()
-{
-	ASSERT(s_instance == nullptr);
-	s_instance = new MMU();
-}
-
-MMU& MMU::get()
-{
-	ASSERT(s_instance);
-	return *s_instance;
-}
-
-static uint64_t* allocate_page_aligned_page()
-{
-	void* page = kmalloc(PAGE_SIZE, PAGE_SIZE);
-	ASSERT(page);
-	memset(page, 0, PAGE_SIZE);
-	return (uint64_t*)page;
-}
-
-MMU::MMU()
-{
-	// Identity map from 4 KiB -> 6 MiB
-	m_highest_paging_struct = allocate_page_aligned_page();
-	
-	uint64_t* pdpt = allocate_page_aligned_page();
-	m_highest_paging_struct[0] = (uint64_t)pdpt | Flags::ReadWrite | Flags::Present;
-
-	uint64_t* pd = allocate_page_aligned_page();
-	pdpt[0] = (uint64_t)pd | Flags::ReadWrite | Flags::Present;
-
-	for (uint32_t i = 0; i < 3; i++)
-	{
-		uint64_t* pt = allocate_page_aligned_page();
-		for (uint64_t j = 0; j < 512; j++)
-			pt[j] = (i << 21) | (j << 12) | Flags::ReadWrite | Flags::Present;
-		pd[i] = (uint64_t)pt | Flags::ReadWrite | Flags::Present;
-	}
-
-	// Unmap 0 -> 4 KiB
-	uint64_t* pt1 = (uint64_t*)(pd[0] & PAGE_MASK);
-	pt1[0] = 0;
-
-	// Load the new pml4
-	asm volatile("movq %0, %%cr3" :: "r"(m_highest_paging_struct));
-}
-
-MMU::~MMU()
-{
-	uint64_t* pml4 = m_highest_paging_struct;
-	for (uint32_t pml4e = 0; pml4e < 512; pml4e++)
-	{
-		if (!(pml4[pml4e] & Flags::Present))
-			continue;
-		uint64_t* pdpt = (uint64_t*)(pml4[pml4e] & PAGE_MASK);
-		for (uint32_t pdpte = 0; pdpte < 512; pdpte++)
-		{
-			if (!(pdpt[pdpte] & Flags::Present))
-				continue;
-			uint64_t* pd = (uint64_t*)(pdpt[pdpte] & PAGE_MASK);
-			for (uint32_t pde = 0; pde < 512; pde++)
-			{
-				if (!(pd[pde] & Flags::Present))
-					continue;
-				kfree((void*)(pd[pde] & PAGE_MASK));
-			}
-			kfree(pd);
-		}
-		kfree(pdpt);
-	}
-	kfree(pml4);
-}
-
-void MMU::allocate_page(uintptr_t address, uint8_t flags)
-{
-	ASSERT((address >> 48) == 0);
-
-	ASSERT(flags & Flags::Present);
-	bool should_invalidate = false;
-
-	address &= PAGE_MASK;
-
-	uint64_t pml4e = (address >> 39) & 0x1FF;
-	uint64_t pdpte = (address >> 30) & 0x1FF;
-	uint64_t pde   = (address >> 21) & 0x1FF;
-	uint64_t pte   = (address >> 12) & 0x1FF;
-
-	uint64_t* pml4 = m_highest_paging_struct;
-	if ((pml4[pml4e] & flags) != flags)
-	{
-		if (!(pml4[pml4e] & Flags::Present))
-			pml4[pml4e] = (uint64_t)allocate_page_aligned_page();
-		pml4[pml4e] = (pml4[pml4e] & PAGE_MASK) | flags;
-		should_invalidate = true;
-	}
-
-	uint64_t* pdpt = (uint64_t*)(pml4[pml4e] & PAGE_MASK);
-	if ((pdpt[pdpte] & flags) != flags)
-	{
-		if (!(pdpt[pdpte] & Flags::Present))
-			pdpt[pdpte] = (uint64_t)allocate_page_aligned_page();
-		pdpt[pdpte] = (pdpt[pdpte] & PAGE_MASK) | flags;
-		should_invalidate = true; 
-	}
-
-	uint64_t* pd = (uint64_t*)(pdpt[pdpte] & PAGE_MASK);
-	if ((pd[pde] & flags) != flags)
-	{
-		if (!(pd[pde] & Flags::Present))
-			pd[pde] = (uint64_t)allocate_page_aligned_page();
-		pd[pde] = (pd[pde] & PAGE_MASK) | flags;
-		should_invalidate = true;
-	}
-
-	uint64_t* pt = (uint64_t*)(pd[pde] & PAGE_MASK);
-	if ((pt[pte] & flags) != flags)
-	{
-		pt[pte] = address | flags;
-		should_invalidate = true;
-	}
-
-	if (should_invalidate)
-		asm volatile("invlpg (%0)" :: "r"(address) : "memory");
-}
-
-void MMU::allocate_range(uintptr_t address, ptrdiff_t size, uint8_t flags)
-{
-	uintptr_t s_page = address & PAGE_MASK;
-	uintptr_t e_page = (address + size - 1) & PAGE_MASK;
-	for (uintptr_t page = s_page; page <= e_page; page += PAGE_SIZE)
-		allocate_page(page, flags);
-}
-
-void MMU::unallocate_page(uintptr_t address)
-{
-	ASSERT((address >> 48) == 0);
-
-	address &= PAGE_MASK;
-
-	uint64_t pml4e = (address >> 39) & 0x1FF;
-	uint64_t pdpte = (address >> 30) & 0x1FF;
-	uint64_t pde   = (address >> 21) & 0x1FF;
-	uint64_t pte   = (address >> 12) & 0x1FF;
-	
-	uint64_t* pml4 = m_highest_paging_struct;
-	if (!(pml4[pml4e] & Flags::Present))
-		return;
-
-	uint64_t* pdpt = (uint64_t*)(pml4[pml4e] & PAGE_MASK);
-	if (!(pdpt[pdpte] & Flags::Present))
-		return;
-
-	uint64_t* pd = (uint64_t*)(pdpt[pdpte] & PAGE_MASK);
-	if (!(pd[pde] & Flags::Present))
-		return;
-
-	uint64_t* pt = (uint64_t*)(pd[pde] & PAGE_MASK);
-	if (!(pt[pte] & Flags::Present))
-		return;
-
-	pt[pte] = 0;
-
-	CLEANUP_STRUCTURE(pt);
-	pd[pde] = 0;
-	CLEANUP_STRUCTURE(pd);
-	pdpt[pdpte] = 0;
-	CLEANUP_STRUCTURE(pdpt);
-	pml4[pml4e] = 0;
-cleanup_done:
-	
-	asm volatile("invlpg (%0)" :: "r"(address) : "memory");
-}
-
-void MMU::unallocate_range(uintptr_t address, ptrdiff_t size)
-{
-	uintptr_t s_page = address & PAGE_MASK;
-	uintptr_t e_page = (address + size - 1) & PAGE_MASK;
-	for (uintptr_t page = s_page; page <= e_page; page += PAGE_SIZE)
-		unallocate_page(page);
-}

kernel/arch/x86_64/PageTable.cpp

@@ -0,0 +1,625 @@
+#include <BAN/Errors.h>
+#include <kernel/Arch.h>
+#include <kernel/CPUID.h>
+#include <kernel/LockGuard.h>
+#include <kernel/Memory/kmalloc.h>
+#include <kernel/Memory/PageTable.h>
+
+extern uint8_t g_kernel_start[];
+extern uint8_t g_kernel_end[];
+
+extern uint8_t g_kernel_execute_start[];
+extern uint8_t g_kernel_execute_end[];
+
+extern uint8_t g_userspace_start[];
+extern uint8_t g_userspace_end[];
+
+namespace Kernel
+{
+
+	static PageTable* s_kernel = nullptr;
+	static PageTable* s_current = nullptr;
+	static bool s_has_nxe = false;
+	static bool s_has_pge = false;
+
+	// PML4 entry for kernel memory
+	static paddr_t s_global_pml4e = 0;
+
+	static constexpr inline bool is_canonical(uintptr_t addr)
+	{
+		constexpr uintptr_t mask = 0xFFFF800000000000;
+		addr &= mask;
+		return addr == mask || addr == 0;
+	}
+
+	static constexpr inline uintptr_t uncanonicalize(uintptr_t addr)
+	{
+		if (addr & 0x0000800000000000)
+			return addr & ~0xFFFF000000000000;
+		return addr;
+	}
+
+	static constexpr inline uintptr_t canonicalize(uintptr_t addr)
+	{
+		if (addr & 0x0000800000000000)
+			return addr | 0xFFFF000000000000;
+		return addr;
+	}
+
+	static inline PageTable::flags_t parse_flags(uint64_t entry)
+	{
+		using Flags = PageTable::Flags;
+
+		PageTable::flags_t result = 0;
+		if (s_has_nxe && !(entry & (1ull << 63)))
+			result |= Flags::Execute;
+		if (entry & Flags::Reserved)
+			result |= Flags::Reserved;
+		if (entry & Flags::CacheDisable)
+			result |= Flags::CacheDisable;
+		if (entry & Flags::UserSupervisor)
+			result |= Flags::UserSupervisor;
+		if (entry & Flags::ReadWrite)
+			result |= Flags::ReadWrite;
+		if (entry & Flags::Present)
+			result |= Flags::Present;
+		return result;
+	}
+
+	void PageTable::initialize()
+	{
+		if (CPUID::has_nxe())
+		{
+			asm volatile(
+				"movl $0xC0000080, %ecx;"
+				"rdmsr;"
+				"orl $0x800, %eax;"
+				"wrmsr"
+			);
+			s_has_nxe = true;
+		}
+
+		uint32_t ecx, edx;
+		CPUID::get_features(ecx, edx);
+		if (edx & CPUID::EDX_PGE)
+		{
+			asm volatile(
+				"movq %cr4, %rax;"
+				"orq $0x80, %rax;"
+				"movq %rax, %cr4;"
+			);
+			s_has_pge = true;
+		}
+
+		ASSERT(s_kernel == nullptr);
+		s_kernel = new PageTable();
+		ASSERT(s_kernel);
+		s_kernel->initialize_kernel();
+		s_kernel->load();
+	}
+
+	PageTable& PageTable::kernel()
+	{
+		ASSERT(s_kernel);
+		return *s_kernel;
+	}
+
+	PageTable& PageTable::current()
+	{
+		ASSERT(s_current);
+		return *s_current;
+	}
+
+	bool PageTable::is_valid_pointer(uintptr_t pointer)
+	{
+		if (!is_canonical(pointer))
+			return false;
+		return true;
+	}
+
+	static uint64_t* allocate_zeroed_page_aligned_page()
+	{
+		void* page = kmalloc(PAGE_SIZE, PAGE_SIZE, true);
+		ASSERT(page);
+		memset(page, 0, PAGE_SIZE);
+		return (uint64_t*)page;
+	}
+
+	void PageTable::initialize_kernel()
+	{
+		ASSERT(s_global_pml4e == 0);
+		s_global_pml4e = V2P(allocate_zeroed_page_aligned_page());
+
+		m_highest_paging_struct = V2P(allocate_zeroed_page_aligned_page());
+		
+		uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
+		pml4[511] = s_global_pml4e;
+
+		// Map (0 -> phys_kernel_end) to (KERNEL_OFFSET -> virt_kernel_end)
+		map_range_at(0, KERNEL_OFFSET, (uintptr_t)g_kernel_end - KERNEL_OFFSET, Flags::ReadWrite | Flags::Present);
+		
+		// Map executable kernel memory as executable
+		map_range_at(
+			V2P(g_kernel_execute_start),
+			(vaddr_t)g_kernel_execute_start,
+			g_kernel_execute_end - g_kernel_execute_start,
+			Flags::Execute | Flags::Present
+		);
+
+		// Map userspace memory
+		map_range_at(
+			V2P(g_userspace_start),
+			(vaddr_t)g_userspace_start,
+			g_userspace_end - g_userspace_start,
+			Flags::Execute | Flags::UserSupervisor | Flags::Present
+		);
+	}
+
+	BAN::ErrorOr<PageTable*> PageTable::create_userspace()
+	{
+		LockGuard _(s_kernel->m_lock);
+		PageTable* page_table = new PageTable;
+		if (page_table == nullptr)
+			return BAN::Error::from_errno(ENOMEM);
+		page_table->map_kernel_memory();
+		return page_table;
+	}
+
+	void PageTable::map_kernel_memory()
+	{
+		ASSERT(s_kernel);
+		ASSERT(s_global_pml4e);
+
+		ASSERT(m_highest_paging_struct == 0);
+		m_highest_paging_struct = V2P(allocate_zeroed_page_aligned_page());
+
+		uint64_t* kernel_pml4 = (uint64_t*)P2V(s_kernel->m_highest_paging_struct);
+
+		uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
+		pml4[511] = kernel_pml4[511];
+	}
+
+	PageTable::~PageTable()
+	{
+		uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
+
+		// NOTE: we only loop until 511 since the last one is the kernel memory
+		for (uint64_t pml4e = 0; pml4e < 511; pml4e++)
+		{
+			if (!(pml4[pml4e] & Flags::Present))
+				continue;
+			uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
+			for (uint64_t pdpte = 0; pdpte < 512; pdpte++)
+			{
+				if (!(pdpt[pdpte] & Flags::Present))
+					continue;
+				uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
+				for (uint64_t pde = 0; pde < 512; pde++)
+				{
+					if (!(pd[pde] & Flags::Present))
+						continue;
+					kfree((void*)P2V(pd[pde] & PAGE_ADDR_MASK));
+				}
+				kfree(pd);
+			}
+			kfree(pdpt);
+		}
+		kfree(pml4);
+	}
+
+	void PageTable::load()
+	{
+		asm volatile("movq %0, %%cr3" :: "r"(m_highest_paging_struct));
+		s_current = this;
+	}
+
+	void PageTable::invalidate(vaddr_t vaddr)
+	{
+		ASSERT(vaddr % PAGE_SIZE == 0);
+		if (this == s_current)
+			asm volatile("invlpg (%0)" :: "r"(vaddr) : "memory");
+	}
+
+	void PageTable::unmap_page(vaddr_t vaddr)
+	{
+		if (vaddr && (vaddr >= KERNEL_OFFSET) != (this == s_kernel))
+			Kernel::panic("unmapping {8H}, kernel: {}", vaddr, this == s_kernel);
+
+		ASSERT(is_canonical(vaddr));
+		vaddr_t uc_vaddr = uncanonicalize(vaddr);
+
+		ASSERT(vaddr % PAGE_SIZE == 0);
+
+		uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
+		uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
+		uint64_t pde   = (uc_vaddr >> 21) & 0x1FF;
+		uint64_t pte   = (uc_vaddr >> 12) & 0x1FF;
+
+		LockGuard _(m_lock);
+
+		if (is_page_free(vaddr))
+		{
+			dwarnln("unmapping unmapped page {8H}", vaddr);
+			return;
+		}
+
+		uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
+		uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
+		uint64_t* pd   = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
+		uint64_t* pt   = (uint64_t*)P2V(pd[pde]     & PAGE_ADDR_MASK);
+
+		pt[pte] = 0;
+		invalidate(vaddr);
+	}
+
+	void PageTable::unmap_range(vaddr_t vaddr, size_t size)
+	{
+		vaddr_t s_page = vaddr / PAGE_SIZE;
+		vaddr_t e_page = BAN::Math::div_round_up<vaddr_t>(vaddr + size, PAGE_SIZE);
+
+		LockGuard _(m_lock);
+		for (vaddr_t page = s_page; page < e_page; page++)
+			unmap_page(page * PAGE_SIZE);
+	}
+
+	void PageTable::map_page_at(paddr_t paddr, vaddr_t vaddr, flags_t flags)
+	{
+		if (vaddr && (vaddr >= KERNEL_OFFSET) != (this == s_kernel))
+			Kernel::panic("mapping {8H} to {8H}, kernel: {}", paddr, vaddr, this == s_kernel);
+
+		ASSERT(is_canonical(vaddr));
+		vaddr_t uc_vaddr = uncanonicalize(vaddr);
+
+		ASSERT(paddr % PAGE_SIZE == 0);
+		ASSERT(vaddr % PAGE_SIZE == 0);
+		ASSERT(flags & Flags::Used);
+
+		uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
+		uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
+		uint64_t pde   = (uc_vaddr >> 21) & 0x1FF;
+		uint64_t pte   = (uc_vaddr >> 12) & 0x1FF;
+
+		uint64_t extra_flags = 0;
+		if (s_has_pge && pml4e == 511) // Map kernel memory as global
+			extra_flags |= 1ull << 8;
+		if (s_has_nxe && !(flags & Flags::Execute))
+			extra_flags |= 1ull << 63;
+		if (flags & Flags::Reserved)
+			extra_flags |= Flags::Reserved;
+		if (flags & Flags::CacheDisable)
+			extra_flags |= Flags::CacheDisable;
+
+		// NOTE: we add present here, since it has to be available in higher level structures
+		flags_t uwr_flags = (flags & (Flags::UserSupervisor | Flags::ReadWrite)) | Flags::Present;
+
+		LockGuard _(m_lock);
+
+		uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
+		if ((pml4[pml4e] & uwr_flags) != uwr_flags)
+		{
+			if (!(pml4[pml4e] & Flags::Present))
+				pml4[pml4e] = V2P(allocate_zeroed_page_aligned_page());
+			pml4[pml4e] |= uwr_flags;
+		}
+
+		uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
+		if ((pdpt[pdpte] & uwr_flags) != uwr_flags)
+		{
+			if (!(pdpt[pdpte] & Flags::Present))
+				pdpt[pdpte] = V2P(allocate_zeroed_page_aligned_page());
+			pdpt[pdpte] |= uwr_flags;
+		}
+
+		uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
+		if ((pd[pde] & uwr_flags) != uwr_flags)
+		{
+			if (!(pd[pde] & Flags::Present))
+				pd[pde] = V2P(allocate_zeroed_page_aligned_page());
+			pd[pde] |= uwr_flags;
+		}
+
+		if (!(flags & Flags::Present))
+			uwr_flags &= ~Flags::Present;
+
+		uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
+		pt[pte] = paddr | uwr_flags | extra_flags;
+
+		invalidate(vaddr);
+	}
+
+	void PageTable::map_range_at(paddr_t paddr, vaddr_t vaddr, size_t size, flags_t flags)
+	{
+		ASSERT(is_canonical(vaddr));
+
+		ASSERT(paddr % PAGE_SIZE == 0);
+		ASSERT(vaddr % PAGE_SIZE == 0);
+
+		size_t first_page = vaddr / PAGE_SIZE;
+		size_t last_page = (vaddr + size - 1) / PAGE_SIZE;
+		size_t page_count = last_page - first_page + 1;
+		
+		LockGuard _(m_lock);
+		for (size_t page = 0; page < page_count; page++)
+			map_page_at(paddr + page * PAGE_SIZE, vaddr + page * PAGE_SIZE, flags);
+	}
+
+	uint64_t PageTable::get_page_data(vaddr_t vaddr) const
+	{
+		ASSERT(is_canonical(vaddr));
+		vaddr_t uc_vaddr = uncanonicalize(vaddr);
+
+		ASSERT(vaddr % PAGE_SIZE == 0);
+
+		uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
+		uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
+		uint64_t pde   = (uc_vaddr >> 21) & 0x1FF;
+		uint64_t pte   = (uc_vaddr >> 12) & 0x1FF;
+		
+		LockGuard _(m_lock);
+
+		uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
+		if (!(pml4[pml4e] & Flags::Present))
+			return 0;
+
+		uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
+		if (!(pdpt[pdpte] & Flags::Present))
+			return 0;
+
+		uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
+		if (!(pd[pde] & Flags::Present))
+			return 0;
+
+		uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
+		if (!(pt[pte] & Flags::Used))
+			return 0;
+
+		return pt[pte];
+	}
+
+	PageTable::flags_t PageTable::get_page_flags(vaddr_t addr) const
+	{
+		return parse_flags(get_page_data(addr));
+	}
+
+	paddr_t PageTable::physical_address_of(vaddr_t addr) const
+	{
+		uint64_t page_data = get_page_data(addr);
+		return (page_data & PAGE_ADDR_MASK) & ~(1ull << 63);
+	}
+
+	bool PageTable::reserve_page(vaddr_t vaddr, bool only_free)
+	{
+		LockGuard _(m_lock);
+		ASSERT(vaddr % PAGE_SIZE == 0);
+		if (only_free && !is_page_free(vaddr))
+			return false;
+		map_page_at(0, vaddr, Flags::Reserved);
+		return true;
+	}
+
+	bool PageTable::reserve_range(vaddr_t vaddr, size_t bytes, bool only_free)
+	{
+		if (size_t rem = bytes % PAGE_SIZE)
+			bytes += PAGE_SIZE - rem;
+		ASSERT(vaddr % PAGE_SIZE == 0);
+
+		LockGuard _(m_lock);
+		if (only_free && !is_range_free(vaddr, bytes))
+			return false;
+		for (size_t offset = 0; offset < bytes; offset += PAGE_SIZE)
+			reserve_page(vaddr + offset);
+		return true;
+	}
+
+	vaddr_t PageTable::reserve_free_page(vaddr_t first_address, vaddr_t last_address)
+	{
+		if (size_t rem = first_address % PAGE_SIZE)
+			first_address += PAGE_SIZE - rem;
+		if (size_t rem = last_address % PAGE_SIZE)
+			last_address -= rem;
+
+		ASSERT(is_canonical(first_address));
+		ASSERT(is_canonical(last_address));
+		const vaddr_t uc_vaddr_start = uncanonicalize(first_address);
+		const vaddr_t uc_vaddr_end   = uncanonicalize(last_address);
+
+		uint16_t pml4e = (uc_vaddr_start >> 39) & 0x1FF;
+		uint16_t pdpte = (uc_vaddr_start >> 30) & 0x1FF;
+		uint16_t pde   = (uc_vaddr_start >> 21) & 0x1FF;
+		uint16_t pte   = (uc_vaddr_start >> 12) & 0x1FF;
+
+		const uint16_t e_pml4e = (uc_vaddr_end >> 39) & 0x1FF;
+		const uint16_t e_pdpte = (uc_vaddr_end >> 30) & 0x1FF;
+		const uint16_t e_pde   = (uc_vaddr_end >> 21) & 0x1FF;
+		const uint16_t e_pte   = (uc_vaddr_end >> 12) & 0x1FF;
+		
+		LockGuard _(m_lock);
+
+		// Try to find free page that can be mapped without
+		// allocations (page table with unused entries)
+		uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
+		for (; pml4e < 512; pml4e++)
+		{
+			if (pml4e > e_pml4e)
+				break;
+			if (!(pml4[pml4e] & Flags::Present))
+				continue;
+			uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
+			for (; pdpte < 512; pdpte++)
+			{
+				if (pml4e == e_pml4e && pdpte > e_pdpte)
+					break;
+				if (!(pdpt[pdpte] & Flags::Present))
+					continue;
+				uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
+				for (; pde < 512; pde++)
+				{
+					if (pml4e == e_pml4e && pdpte == e_pdpte && pde > e_pde)
+						break;
+					if (!(pd[pde] & Flags::Present))
+						continue;
+					uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
+					for (; pte < 512; pte++)
+					{
+						if (pml4e == e_pml4e && pdpte == e_pdpte && pde == e_pde && pte >= e_pte)
+							break;
+						if (!(pt[pte] & Flags::Used))
+						{
+							vaddr_t vaddr = 0;
+							vaddr |= (uint64_t)pml4e << 39;
+							vaddr |= (uint64_t)pdpte << 30;
+							vaddr |= (uint64_t)pde   << 21;
+							vaddr |= (uint64_t)pte   << 12;
+							ASSERT(reserve_page(vaddr));
+							return canonicalize(vaddr);
+						}
+					}
+				}
+			}
+		}
+
+		// Find any free page
+		vaddr_t uc_vaddr = uc_vaddr_start;
+		while (uc_vaddr < uc_vaddr_end)
+		{
+			if (vaddr_t vaddr = canonicalize(uc_vaddr); is_page_free(vaddr))
+			{
+				ASSERT(reserve_page(vaddr));
+				return vaddr;
+			}
+			uc_vaddr += PAGE_SIZE;
+		}
+
+		ASSERT_NOT_REACHED();
+	}
+
+	vaddr_t PageTable::reserve_free_contiguous_pages(size_t page_count, vaddr_t first_address, vaddr_t last_address)
+	{
+		if (size_t rem = first_address % PAGE_SIZE)
+			first_address += PAGE_SIZE - rem;
+		if (size_t rem = last_address % PAGE_SIZE)
+			last_address -= rem;
+
+		ASSERT(is_canonical(first_address));
+		ASSERT(is_canonical(last_address));
+
+		LockGuard _(m_lock);
+
+		for (vaddr_t vaddr = first_address; vaddr < last_address;)
+		{
+			bool valid { true };
+			for (size_t page = 0; page < page_count; page++)
+			{
+				if (!is_canonical(vaddr + page * PAGE_SIZE))
+				{
+					vaddr = canonicalize(uncanonicalize(vaddr) + page * PAGE_SIZE);
+					valid = false;
+					break;
+				}
+				if (!is_page_free(vaddr + page * PAGE_SIZE))
+				{
+					vaddr += (page + 1) * PAGE_SIZE;
+					valid = false;
+					break;
+				}
+			}
+			if (valid)
+			{
+				ASSERT(reserve_range(vaddr, page_count * PAGE_SIZE));
+				return vaddr;
+			}
+		}
+
+		ASSERT_NOT_REACHED();
+	}
+
+	bool PageTable::is_page_free(vaddr_t page) const
+	{
+		ASSERT(page % PAGE_SIZE == 0);
+		return !(get_page_flags(page) & Flags::Used);
+	}
+
+	bool PageTable::is_range_free(vaddr_t vaddr, size_t size) const
+	{
+		vaddr_t s_page = vaddr / PAGE_SIZE;
+		vaddr_t e_page = BAN::Math::div_round_up<vaddr_t>(vaddr + size, PAGE_SIZE);
+
+		LockGuard _(m_lock);
+		for (vaddr_t page = s_page; page < e_page; page++)
+			if (!is_page_free(page * PAGE_SIZE))
+				return false;
+		return true;
+	}
+
+	static void dump_range(vaddr_t start, vaddr_t end, PageTable::flags_t flags)
+	{
+		if (start == 0)
+			return;
+		dprintln("{}-{}: {}{}{}{}",
+			(void*)canonicalize(start),
+			(void*)canonicalize(end - 1),
+			flags & PageTable::Flags::Execute			? 'x' : '-',
+			flags & PageTable::Flags::UserSupervisor	? 'u' : '-',
+			flags & PageTable::Flags::ReadWrite			? 'w' : '-',
+			flags & PageTable::Flags::Present			? 'r' : '-'
+		);
+	}
+
+	void PageTable::debug_dump()
+	{
+		LockGuard _(m_lock);
+
+		flags_t flags = 0;
+		vaddr_t start = 0;
+
+		uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
+		for (uint64_t pml4e = 0; pml4e < 512; pml4e++)
+		{
+			if (!(pml4[pml4e] & Flags::Present))
+			{
+				dump_range(start, (pml4e << 39), flags);
+				start = 0;
+				continue;
+			}
+			uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
+			for (uint64_t pdpte = 0; pdpte < 512; pdpte++)
+			{
+				if (!(pdpt[pdpte] & Flags::Present))
+				{
+					dump_range(start, (pml4e << 39) | (pdpte << 30), flags);
+					start = 0;
+					continue;
+				}
+				uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
+				for (uint64_t pde = 0; pde < 512; pde++)
+				{
+					if (!(pd[pde] & Flags::Present))
+					{
+						dump_range(start, (pml4e << 39) | (pdpte << 30) | (pde << 21), flags);
+						start = 0;
+						continue;
+					}
+					uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
+					for (uint64_t pte = 0; pte < 512; pte++)
+					{
+						if (parse_flags(pt[pte]) != flags)
+						{
+							dump_range(start, (pml4e << 39) | (pdpte << 30) | (pde << 21) | (pte << 12), flags);
+							start = 0;
+						}
+
+						if (!(pt[pte] & Flags::Used))
+							continue;
+						
+						if (start == 0)
+						{
+							flags = parse_flags(pt[pte]);
+							start = (pml4e << 39) | (pdpte << 30) | (pde << 21) | (pte << 12);
+						}
+					}
+				}
+			}
+		}
+	}
+
+}

kernel/arch/x86_64/Signal.S

@@ -0,0 +1,57 @@
+.section .userspace, "aw"
+
+#include <sys/syscall.h>
+
+// stack contains
+//    return address
+//    signal number
+//    signal handler
+
+.global signal_trampoline
+signal_trampoline:
+	pushq %rax
+	pushq %rbx
+	pushq %rcx
+	pushq %rdx
+	pushq %rbp
+	pushq %rdi
+	pushq %rsi
+	pushq %r8
+	pushq %r9
+	pushq %r10
+	pushq %r11
+	pushq %r12
+	pushq %r13
+	pushq %r14
+	pushq %r15
+
+	// This is 16 byte aligned
+
+	movq 128(%rsp), %rdi
+	movq 120(%rsp), %rax
+	call *%rax
+
+	movq $SYS_SIGNAL_DONE, %rax
+	movq 128(%rsp), %rbx
+	int $0x80
+
+	popq %r15
+	popq %r14
+	popq %r13
+	popq %r12
+	popq %r11
+	popq %r10
+	popq %r9
+	popq %r8
+	popq %rsi
+	popq %rdi
+	popq %rbp
+	popq %rdx
+	popq %rcx
+	popq %rbx
+	popq %rax
+
+	addq $16, %rsp
+
+	// return over red-zone
+	ret $128

kernel/arch/x86_64/SpinLock.S

@@ -1,17 +0,0 @@
-.global spinlock_lock_asm
-spinlock_lock_asm:
-	lock; btsq $0, (%rdi)
-	jnc .done
-.retry:
-	pause
-	testq $1, (%rdi)
-	jne .retry
-	lock; btsq $0, (%rdi)
-	jc .retry
-.done:
-	ret
-
-.global spinlock_unlock_asm
-spinlock_unlock_asm:
-	movl $0, (%rdi)
-	ret

kernel/arch/x86_64/Thread.S

@@ -23,4 +23,17 @@ start_thread:
 continue_thread:
 	movq %rdi, %rsp
 	movq $0, %rax
-	jmp *%rsi
+	jmp *%rsi
+
+# void thread_userspace_trampoline(uint64_t rsp, uint64_t rip, int argc, char** argv, char** envp)
+.global thread_userspace_trampoline
+thread_userspace_trampoline:
+	pushq $0x23
+	pushq %rdi
+	pushfq
+	pushq $0x1B
+	pushq %rsi
+	movq %rdx, %rdi
+	movq %rcx, %rsi
+	movq %r8, %rdx
+	iretq

kernel/arch/x86_64/boot.S

@@ -10,6 +10,9 @@
 .set PG_READ_WRITE,	1<<1
 .set PG_PAGE_SIZE,	1<<7
 
+#define KERNEL_OFFSET 0xFFFFFFFF80000000
+#define V2P(vaddr) ((vaddr) - KERNEL_OFFSET)
+
 .code32
 
 # Multiboot header
@@ -32,34 +35,45 @@
 		.skip 16384
 	.global g_boot_stack_top
 	g_boot_stack_top:
-	
+
 	.global g_kernel_cmdline
 	g_kernel_cmdline:
 		.skip 4096
 
-	# Reserve memory for paging structures,
-	# we will identity map first 4 MiB
+	.global g_multiboot_info
+	g_multiboot_info:
+		.skip 8
+	.global g_multiboot_magic
+	g_multiboot_magic:
+		.skip 8
 
-	# 0 MiB -> 1 MiB: bootloader stuff
-	# 1 MiB -> 4 MiB: kernel
-	# 4 MiB -> 5 MiB: kmalloc
-	# 5 MiB -> 6 MiB: kmalloc_fixed
-	.align 4096
-	boot_pml4:
-		.skip 512 * 8
-	boot_pdpt1:
-		.skip 512 * 8
-	boot_pd1:
-		.skip 512 * 8
+.section .data
 
-.global g_multiboot_info
-g_multiboot_info:
-	.skip 8
-.global g_multiboot_magic
-g_multiboot_magic:
-	.skip 8
-
-.section .text
+# Map first GiB to 0x00000000 and 0xFFFFFFFF80000000
+.align 4096
+boot_pml4:
+	.quad V2P(boot_pdpt_lo) + (PG_READ_WRITE | PG_PRESENT)
+	.rept 510
+		.quad 0
+	.endr
+	.quad V2P(boot_pdpt_hi) + (PG_READ_WRITE | PG_PRESENT)
+boot_pdpt_lo:
+	.quad V2P(boot_pd) + (PG_READ_WRITE | PG_PRESENT)
+	.rept 511
+		.quad 0
+	.endr
+boot_pdpt_hi:
+	.rept 510
+		.quad 0
+	.endr
+	.quad V2P(boot_pd) + (PG_READ_WRITE | PG_PRESENT)
+	.quad 0
+boot_pd:
+	.set i, 0
+	.rept 512
+		.quad i + (PG_PAGE_SIZE | PG_READ_WRITE | PG_PRESENT)
+		.set i, i + 0x200000
+	.endr
 
 boot_gdt:
 	.quad 0x0000000000000000 # null descriptor
@@ -67,7 +81,9 @@ boot_gdt:
 	.quad 0x00AF92000000FFFF # kernel data
 boot_gdtr:
 	.short . - boot_gdt - 1
-	.quad boot_gdt
+	.quad V2P(boot_gdt)
+
+.section .text
 
 has_cpuid:
 	pushfl
@@ -106,11 +122,11 @@ check_requirements:
 copy_kernel_commandline:
 	pushl %esi
 	pushl %edi
-	movl g_multiboot_info, %esi
+	movl V2P(g_multiboot_info), %esi
 	addl $16, %esi
 	movl (%esi), %esi
 	movl $1024, %ecx
-	movl $g_kernel_cmdline, %edi
+	movl $V2P(g_kernel_cmdline), %edi
 	rep movsl
 	popl %edi
 	popl %esi
@@ -127,15 +143,6 @@ enable_sse:
 	ret
 
 initialize_paging:
-	# identity map first 6 MiB
-	movl $(0x00000000 + PG_PAGE_SIZE + PG_READ_WRITE + PG_PRESENT), boot_pd1 + 0
-	movl $(0x00200000 + PG_PAGE_SIZE + PG_READ_WRITE + PG_PRESENT), boot_pd1 + 8
-	movl $(0x00400000 + PG_PAGE_SIZE + PG_READ_WRITE + PG_PRESENT), boot_pd1 + 16
-
-	# set pdpte1 and pml4e1
-	movl $(boot_pd1   + PG_READ_WRITE + PG_PRESENT), boot_pdpt1	
-	movl $(boot_pdpt1 + PG_READ_WRITE + PG_PRESENT), boot_pml4
-
 	# enable PAE
 	movl %cr4, %ecx
 	orl $0x20, %ecx
@@ -148,7 +155,7 @@ initialize_paging:
 	wrmsr
 
 	# set address of paging structures
-	movl $boot_pml4, %ecx
+	movl $V2P(boot_pml4), %ecx
 	movl %ecx, %cr3
 
 	# enable paging
@@ -162,9 +169,9 @@ initialize_paging:
 .type _start, @function
 _start:
 	# Initialize stack and multiboot info
-	movl $g_boot_stack_top, %esp
-	movl %eax, g_multiboot_magic
-	movl %ebx, g_multiboot_info
+	movl $V2P(g_boot_stack_top), %esp
+	movl %eax, V2P(g_multiboot_magic)
+	movl %ebx, V2P(g_multiboot_info)
 
 	call copy_kernel_commandline
 	call check_requirements
@@ -173,8 +180,8 @@ _start:
 	call initialize_paging
 
 	# flush gdt and jump to 64 bit
-	lgdt boot_gdtr
-	ljmpl $0x08, $long_mode
+	lgdt V2P(boot_gdtr)
+	ljmpl $0x08, $V2P(long_mode)
 
 .code64
 long_mode:
@@ -188,6 +195,14 @@ long_mode:
 	movw %ax, %fs
 	movw %ax, %gs
 
+	# jump to higher half
+	movq $g_boot_stack_top, %rsp
+	movabsq $higher_half, %rcx
+	jmp *%rcx
+
+higher_half:
+	addq $KERNEL_OFFSET, g_multiboot_info
+
 	# call global constuctors
 	call _init
 

kernel/arch/x86_64/crt0.S

@@ -0,0 +1,34 @@
+.section .text
+
+.global _start
+_start:
+	# Set up end of the stack frame linked list.
+	movq $0, %rbp
+	pushq %rbp # rip=0
+	pushq %rbp # rbp=0
+	movq %rsp, %rbp
+
+	# We need those in a moment when we call main.
+	pushq %rdx
+	pushq %rsi
+	pushq %rdi
+
+	# Prepare signals, memory allocation, stdio and such.
+	movq %rdx, %rdi
+	call _init_libc
+
+	# Run the global constructors.
+	call _init
+
+	# Restore argc and argv.
+	popq %rdi
+	popq %rsi
+	popq %rdx
+
+	# Run main
+	call main
+
+	# Terminate the process with the exit code.
+	movl %eax, %edi
+	call exit
+.size _start, . - _start

kernel/arch/x86_64/interrupts.S

@@ -64,7 +64,11 @@ isr_stub:
 
 	movq 176(%rsp), %rdi
 	movq 184(%rsp), %rsi
+
 	movq %rsp, %rdx
+	addq $192, %rdx
+
+	movq %rsp, %rcx
 
 	call cpp_isr_handler
 	addq $56, %rsp
@@ -75,6 +79,8 @@ isr_stub:
 irq_stub:
 	pushaq
 	movq 0x78(%rsp), %rdi	# irq number
+	movq %rsp, %rsi
+	addq $136, %rsi
 	call cpp_irq_handler
 	popaq
 	addq $16, %rsp
@@ -83,7 +89,6 @@ irq_stub:
 .macro isr n
 	.global isr\n
 	isr\n:
-		cli
 		pushq $0
 		pushq $\n
 		jmp isr_stub
@@ -92,7 +97,6 @@ irq_stub:
 .macro isr_err n
 	.global isr\n
 	isr\n:
-		cli
 		pushq $\n
 		jmp isr_stub
 .endm
@@ -100,7 +104,6 @@ irq_stub:
 .macro irq n
 	.global irq\n
 	irq\n:
-		cli
 		pushq $0
 		pushq $\n
 		jmp irq_stub
@@ -156,14 +159,21 @@ irq 13
 irq 14
 irq 15
 
+// arguments in RAX, RBX, RCX, RDX, RSI, RDI
+// System V ABI: RDI, RSI, RDX, RCX, R8, R9
 .global syscall_asm
 syscall_asm:
-	cli
 	pushaq
+	movq %rsi, %r8
+	movq %rdi, %r9
 	movq %rax, %rdi
 	movq %rbx, %rsi
 	xchgq %rcx, %rdx
+	movq %rsp, %rbx
+	addq $120, %rbx
+	pushq %rbx
 	call cpp_syscall_handler
+	addq $8, %rsp
 	popaq_no_rax
 	addq $8, %rsp
 	iretq

kernel/arch/x86_64/linker.ld

@@ -1,38 +1,37 @@
 ENTRY (_start)
 
+KERNEL_OFFSET = 0xFFFFFFFF80000000;
+
 SECTIONS
 {
-	. = 0x00100000;
+	. = 0x00100000 + KERNEL_OFFSET;
 
-	.text BLOCK(4K) : ALIGN(4K)
+	g_kernel_start = .;
+	.text ALIGN(4K) : AT(ADDR(.text) - KERNEL_OFFSET)
 	{
+		g_kernel_execute_start = .;
 		*(.multiboot)
-		*(.text)
+		*(.text.*)
 	}
-	.rodata BLOCK(4K) : ALIGN(4K)
+	.userspace ALIGN(4K) : AT(ADDR(.userspace) - KERNEL_OFFSET)
 	{
-		g_rodata_start = .;
-		*(.rodata.*)
-		g_rodata_end = .;
+		g_userspace_start = .;
+		*(.userspace)
+		g_userspace_end = .;
 	}
-	.data BLOCK(4K) : ALIGN(4K)
+	.rodata ALIGN(4K) : AT(ADDR(.rodata) - KERNEL_OFFSET)
+	{
+		*(.rodata.*)
+		g_kernel_execute_end = .;
+	}
+	.data ALIGN(4K) : AT(ADDR(.data) - KERNEL_OFFSET)
 	{
 		*(.data)
 	}
-	.bss BLOCK(4K) : ALIGN(4K)
+	.bss ALIGN(4K) : AT(ADDR(.bss) - KERNEL_OFFSET)
 	{
 		*(COMMON)
 		*(.bss)
 	}
 	g_kernel_end = .;
-
-	. = 0x00A00000;
-
-	g_userspace_start = .;
-	.userspace BLOCK(4K) : ALIGN(4K)
-	{
-		*(.userspace)
-	}
-	g_userspace_end = .;
-
 }

kernel/arch/x86_64/make.config

@@ -1,16 +0,0 @@
-KERNEL_ARCH_CFLAGS=-mcmodel=large -mno-red-zone -mno-mmx
-KERNEL_ARCH_CPPFLAGS=
-KERNEL_ARCH_LDFLAGS=-z max-page-size=4096
-KERNEL_ARCH_LIBS=
- 
-ELF_FORMAT=elf64-x86-64
-
-KERNEL_ARCH_OBJS=		\
-$(ARCHDIR)/boot.o		\
-$(ARCHDIR)/GDT.o		\
-$(ARCHDIR)/IDT.o		\
-$(ARCHDIR)/interrupts.o	\
-$(ARCHDIR)/MMU.o		\
-$(ARCHDIR)/SpinLock.o	\
-$(ARCHDIR)/Thread.o		\
- 

kernel/icxxabi.cpp

@@ -104,7 +104,7 @@ void __cxa_finalize(void *f)
 			**/
 			(*__atexit_funcs[i].destructor_func)(__atexit_funcs[i].obj_ptr);
 			__atexit_funcs[i].destructor_func = 0;
- 
+
 			/*
 			* Notice that we didn't decrement __atexit_func_count: this is because this algorithm
 			* requires patching to deal with the FIXME outlined above.
@@ -113,8 +113,6 @@ void __cxa_finalize(void *f)
 	};
 };
 
-
-
 namespace __cxxabiv1 
 {
 	/* guard variables */
@@ -122,19 +120,19 @@ namespace __cxxabiv1
 
 	/* The ABI requires a 64-bit type.  */
 	__extension__ typedef int __guard __attribute__((mode(__DI__)));
- 
+
 	int __cxa_guard_acquire (__guard* g)
 	{
 		Kernel::LockGuard lock_guard(s_spin_lock);
 		return !*(int*)g;
 	}
- 
+
 	void __cxa_guard_release (__guard* g)
 	{
 		Kernel::LockGuard lock_guard(s_spin_lock);
 		*(int*)g = 1;
 	}
- 
+
 	void __cxa_guard_abort (__guard*)
 	{
 		Kernel::panic("__cxa_guard_abort");

kernel/include/kernel/ACPI.h

@@ -0,0 +1,144 @@
+#pragma once
+
+#include <BAN/Vector.h>
+#include <kernel/Memory/Types.h>
+
+namespace Kernel
+{
+
+	class ACPI
+	{
+	public:
+		struct GAS
+		{
+			uint8_t address_space_id;
+			uint8_t register_bit_width;
+			uint8_t register_bit_offset;
+			uint8_t access_size;
+			uint64_t address;
+		} __attribute__((packed));
+
+		struct SDTHeader
+		{
+			uint8_t signature[4];
+			uint32_t length;
+			uint8_t revision;
+			uint8_t checksum;
+			uint8_t oemid[6];
+			uint64_t oem_table_id;
+			uint32_t oem_revision;
+			uint32_t creator_id;
+			uint32_t creator_revision;
+		} __attribute__((packed));
+
+		struct FADT : public SDTHeader
+		{
+			uint32_t firmware_ctrl;
+			uint32_t dsdt;
+			uint8_t __reserved;
+			uint8_t preferred_pm_profile;
+			uint16_t sci_int;
+			uint32_t smi_cmd;
+			uint8_t acpi_enable;
+			uint8_t acpi_disable;
+			uint8_t s4bios_req;
+			uint8_t pstate_cnt;
+			uint32_t pm1a_evt_blk;
+			uint32_t pm1b_evt_blk;
+			uint32_t pm1a_cnt_blk;
+			uint32_t pm1b_cnt_blk;
+			uint32_t pm2_cnt_blk;
+			uint32_t pm_tmr_blk;
+			uint32_t gpe0_blk;
+			uint32_t gpe1_blk;
+			uint8_t pm1_evt_len;
+			uint8_t pm1_cnt_len;
+			uint8_t pm2_cnt_len;
+			uint8_t pm_tmr_len;
+			uint8_t gpe0_blk_len;
+			uint8_t gpe1_blk_len;
+			uint8_t gpe1_base;
+			uint8_t cst_cnt;
+			uint16_t p_lvl2_lat;
+			uint16_t p_lvl3_lat;
+			uint16_t flush_size;
+			uint16_t flush_stride;
+			uint8_t duty_offset;
+			uint8_t duty_width;
+			uint8_t day_alrm;
+			uint8_t mon_alrm;
+			uint8_t century;
+			uint16_t iapc_boot_arch;
+			uint8_t __reserved2;
+			uint32_t flags;
+			uint8_t reset_reg[12];
+			uint8_t reset_value;
+			uint16_t arm_boot_arch;
+			uint8_t fadt_minor_version;
+			uint64_t x_firmware_version;
+			uint64_t x_dsdt;
+			uint8_t x_pm1a_evt_blk[12];
+			uint8_t x_pm1b_evt_blk[12];
+			uint8_t x_pm1a_cnt_blk[12];
+			uint8_t x_pm1b_cnt_blk[12];
+			uint8_t x_pm2_cnt_blk[12];
+			uint8_t x_pm_tmr_blk[12];
+			uint8_t x_gpe0_blk[12];
+			uint8_t x_gpe1_blk[12];
+			uint8_t sleep_control_reg[12];
+			uint8_t sleep_status_reg[12];
+			uint64_t hypervison_vendor_identity;
+		} __attribute__((packed));
+
+		struct HPET : public SDTHeader
+		{
+			uint8_t hardware_rev_id;
+			uint8_t comparator_count : 5;
+			uint8_t count_size_cap : 1;
+			uint8_t reserved : 1;
+			uint8_t legacy_replacement_irq_routing_cable : 1;
+			uint16_t pci_vendor_id;
+			GAS base_address;
+			uint8_t hpet_number;
+			uint16_t main_counter_minimum_clock_tick;
+			uint8_t page_protection_and_oem_attribute;
+		} __attribute__((packed));
+
+	public:
+		static BAN::ErrorOr<void> initialize();
+		static ACPI& get();
+
+		const SDTHeader* get_header(const char[4]);
+
+	private:
+		ACPI() = default;
+		BAN::ErrorOr<void> initialize_impl();
+
+	private:
+		paddr_t m_header_table_paddr = 0;
+		vaddr_t m_header_table_vaddr = 0;
+		uint32_t m_entry_size = 0;
+
+		struct MappedPage
+		{
+			Kernel::paddr_t paddr;
+			Kernel::vaddr_t vaddr;
+
+			SDTHeader* as_header() { return (SDTHeader*)vaddr; }
+		};
+		BAN::Vector<MappedPage> m_mapped_headers;		
+	};
+
+}
+
+namespace BAN::Formatter
+{
+	template<typename F>
+	void print_argument(F putc, const Kernel::ACPI::SDTHeader& header, const ValueFormat& format)
+	{ 
+		putc(header.signature[0]);
+		putc(header.signature[1]);
+		putc(header.signature[2]);
+		putc(header.signature[3]);
+	}
+}

kernel/include/kernel/API/DirectoryEntry.h

@@ -0,0 +1,21 @@
+#pragma once
+
+#include <dirent.h>
+
+namespace Kernel::API
+{
+
+	struct DirectoryEntry
+	{
+		size_t rec_len { 0 };
+		struct dirent dirent;
+		DirectoryEntry* next() const { return (DirectoryEntry*)((uintptr_t)this + rec_len); }
+	};
+
+	struct DirectoryEntryList
+	{
+		size_t entry_count { 0 };
+		DirectoryEntry array[];
+	};
+
+}

kernel/include/kernel/APIC.h

@@ -2,6 +2,7 @@
 
 #include <BAN/Vector.h>
 #include <kernel/InterruptController.h>
+#include <kernel/Memory/Types.h>
 
 class APIC final : public InterruptController
 {
@@ -15,6 +16,7 @@ private:
 	void write_to_local_apic(ptrdiff_t, uint32_t);
 
 private:
+	~APIC() { ASSERT_NOT_REACHED(); }
 	static APIC* create();
 	friend class InterruptController;
 
@@ -34,7 +36,8 @@ private:
 	struct IOAPIC
 	{
 		uint8_t id;
-		uintptr_t address;
+		Kernel::paddr_t paddr;
+		Kernel::vaddr_t vaddr;
 		uint32_t gsi_base;
 		uint8_t max_redirs;
 
@@ -44,7 +47,8 @@ private:
 
 private:
 	BAN::Vector<Processor>	m_processors;
-	uintptr_t				m_local_apic = 0;
+	Kernel::paddr_t			m_local_apic_paddr = 0;
+	Kernel::vaddr_t			m_local_apic_vaddr = 0;
 	BAN::Vector<IOAPIC>		m_io_apics;	
 	uint8_t					m_irq_overrides[0x100] {};
 };

kernel/include/kernel/Arch.h

@@ -17,4 +17,12 @@
 	#define read_rsp(rsp) asm volatile("movl %%esp, %0" : "=r"(rsp))
 	#define push_callee_saved() asm volatile("pushal")
 	#define pop_callee_saved() asm volatile("popal")
-#endif
+#endif
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" uintptr_t read_rip();
+#else
+extern uintptr_t read_rip();
+#endif

kernel/include/kernel/CPUID.h

@@ -73,9 +73,10 @@ namespace CPUID
 
 	const char* feature_string_ecx(uint32_t feat);
 	const char* feature_string_edx(uint32_t feat);
-	
+
 	const char* get_vendor();
 	void get_features(uint32_t& ecx, uint32_t& edx);
 	bool is_64_bit();
+	bool has_nxe();
 
 }

kernel/include/kernel/Credentials.h

@@ -0,0 +1,50 @@
+#pragma once
+
+#include <sys/types.h>
+
+namespace Kernel
+{
+
+	class Credentials
+	{
+	public:
+		Credentials(uid_t ruid, uid_t euid, gid_t rgid, gid_t egid)
+			: m_ruid(ruid), m_euid(euid), m_suid(0)
+			, m_rgid(rgid), m_egid(egid), m_sgid(0)
+		{ }
+
+		uid_t ruid() const { return m_ruid; }
+		uid_t euid() const { return m_euid; }
+		uid_t suid() const { return m_suid; }
+
+		gid_t rgid() const { return m_rgid; }
+		gid_t egid() const { return m_egid; }
+		gid_t sgid() const { return m_sgid; }
+
+		void set_ruid(uid_t uid) { m_ruid = uid; }
+		void set_euid(uid_t uid) { m_euid = uid; }
+		void set_suid(uid_t uid) { m_suid = uid; }
+
+		void set_rgid(gid_t gid) { m_rgid = gid; }
+		void set_egid(gid_t gid) { m_egid = gid; }
+		void set_sgid(gid_t gid) { m_sgid = gid; }
+
+		bool is_superuser() const { return m_euid == 0; }
+
+	private:
+		uid_t m_ruid, m_euid, m_suid;
+		gid_t m_rgid, m_egid, m_sgid;
+	};
+
+}
+
+namespace BAN::Formatter
+{
+
+	template<typename F>
+	void print_argument(F putc, const Kernel::Credentials& credentials, const ValueFormat&)
+	{
+		print(putc, "(ruid {}, euid {})", credentials.ruid(), credentials.euid());
+	}
+
+}

kernel/include/kernel/CriticalScope.h

@@ -11,7 +11,7 @@ namespace Kernel
 	{
 		BAN_NON_COPYABLE(CriticalScope);
 		BAN_NON_MOVABLE(CriticalScope);
-	
+
 	public:
 		CriticalScope()
 		{