BuildSystem: using sysroot doesn't need root privileges anymore!

Sysroot is now created with fakeroot. This allows root access to be
only needed for disk image creation, since it uses loopback devices.

.gitignore

@@ -2,4 +2,4 @@
 .idea/
 build/
 base/
-
+script/fakeroot-context

BAN/BAN/String.cpp

@@ -1,6 +1,5 @@
 #include <BAN/String.h>
 #include <BAN/New.h>
-#include <BAN/Variant.h>
 
 namespace BAN
 {
@@ -32,8 +31,7 @@ namespace BAN
 	String& String::operator=(const String& other)
 	{
 		clear();
-		if (!other.fits_in_sso())
-			MUST(ensure_capacity(other.size()));
+		MUST(ensure_capacity(other.size()));
 		memcpy(data(), other.data(), other.size() + 1);
 		m_size = other.size();
 		return *this;
@@ -43,14 +41,18 @@ namespace BAN
 	{
 		clear();
 
-		if (other.fits_in_sso())
+		if (other.has_sso())
 			memcpy(data(), other.data(), other.size() + 1);
 		else
-			m_storage = other.m_storage.get<GeneralStorage>();
+		{
+			m_storage.general_storage = other.m_storage.general_storage;
+			m_has_sso = false;
+		}
 		m_size = other.m_size;
 
 		other.m_size = 0;
-		other.m_storage = SSOStorage();
+		other.m_storage.sso_storage = SSOStorage();
+		other.m_has_sso = true;
 
 		return *this;
 	}
@@ -58,8 +60,7 @@ namespace BAN
 	String& String::operator=(StringView other)
 	{
 		clear();
-		if (!fits_in_sso(other.size()))
-			MUST(ensure_capacity(other.size()));
+		MUST(ensure_capacity(other.size()));
 		memcpy(data(), other.data(), other.size());
 		m_size = other.size();
 		data()[m_size] = '\0';
@@ -125,8 +126,9 @@ namespace BAN
 	{
 		if (!has_sso())
 		{
-			deallocator(m_storage.get<GeneralStorage>().data);
-			m_storage = SSOStorage();
+			deallocator(m_storage.general_storage.data);
+			m_storage.sso_storage = SSOStorage();
+			m_has_sso = true;
 		}
 		m_size = 0;
 		data()[m_size] = '\0';
@@ -166,15 +168,6 @@ namespace BAN
 			data()[m_size] = '\0';
 			return {};
 		}
-		
-		// shrink general -> sso
-		if (!has_sso() && fits_in_sso(new_size))
-		{
-			char* data = m_storage.get<GeneralStorage>().data;
-			m_storage = SSOStorage();
-			memcpy(m_storage.get<SSOStorage>().storage, data, new_size);
-			deallocator(data);
-		}
 
 		m_size = new_size;
 		data()[m_size] = '\0';
@@ -194,20 +187,21 @@ namespace BAN
 
 		if (fits_in_sso())
 		{
-			char* data = m_storage.get<GeneralStorage>().data;
-			m_storage = SSOStorage();
-			memcpy(m_storage.get<SSOStorage>().storage, data, m_size + 1);
+			char* data = m_storage.general_storage.data;
+			m_storage.sso_storage = SSOStorage();
+			m_has_sso = true;
+			memcpy(this->data(), data, m_size + 1);
 			deallocator(data);
 			return {};
 		}
 
-		GeneralStorage& storage = m_storage.get<GeneralStorage>();
+		GeneralStorage& storage = m_storage.general_storage;
 		if (storage.capacity == m_size)
 			return {};
 
 		char* new_data = (char*)allocator(m_size + 1);
 		if (new_data == nullptr)
-			return BAN::Error::from_errno(ENOMEM);
+			return Error::from_errno(ENOMEM);
 
 		memcpy(new_data, storage.data, m_size);
 		deallocator(storage.data);
@@ -222,40 +216,45 @@ namespace BAN
 	{
 		if (has_sso())
 			return sso_capacity;
-		return m_storage.get<GeneralStorage>().capacity;
+		return m_storage.general_storage.capacity;
 	}
 
 	char* String::data()
 	{
 		if (has_sso())
-			return m_storage.get<SSOStorage>().storage;
-		return m_storage.get<GeneralStorage>().data;
+			return m_storage.sso_storage.data;
+		return m_storage.general_storage.data;
 	}
 
 	const char* String::data() const
 	{
 		if (has_sso())
-			return m_storage.get<SSOStorage>().storage;
-		return m_storage.get<GeneralStorage>().data;
+			return m_storage.sso_storage.data;
+		return m_storage.general_storage.data;
 	}
 
 	ErrorOr<void> String::ensure_capacity(size_type new_size)
 	{
-		if (m_size >= new_size || fits_in_sso(new_size))
+		if (m_size >= new_size)
+			return {};
+		if (has_sso() && fits_in_sso(new_size))
 			return {};
 		
 		char* new_data = (char*)allocator(new_size + 1);
 		if (new_data == nullptr)
-			return BAN::Error::from_errno(ENOMEM);
+			return Error::from_errno(ENOMEM);
 		
 		memcpy(new_data, data(), m_size + 1);
 
 		if (has_sso())
-			m_storage = GeneralStorage();
+		{
+			m_storage.general_storage = GeneralStorage();
+			m_has_sso = false;
+		}
 		else
-			deallocator(m_storage.get<GeneralStorage>().data);
+			deallocator(m_storage.general_storage.data);
 
-		auto& storage = m_storage.get<GeneralStorage>();
+		auto& storage = m_storage.general_storage;
 		storage.capacity = new_size;
 		storage.data = new_data;
 
@@ -264,7 +263,7 @@ namespace BAN
 
 	bool String::has_sso() const
 	{
-		return m_storage.has<SSOStorage>();
+		return m_has_sso;
 	}
 
 }

BAN/CMakeLists.txt

@@ -10,17 +10,15 @@ set(BAN_SOURCES
 )
 
 add_custom_target(ban-headers
-	COMMAND sudo rsync -a ${CMAKE_CURRENT_SOURCE_DIR}/include/ ${BANAN_INCLUDE}/
+	COMMAND ${CMAKE_COMMAND} -E copy_directory_if_different ${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}/
+	COMMAND ${CMAKE_COMMAND} -E copy_if_different ${CMAKE_CURRENT_BINARY_DIR}/libban.a ${BANAN_LIB}/
 	DEPENDS ban
 	BYPRODUCTS ${BANAN_LIB}/libban.a
-	USES_TERMINAL
 )

BAN/include/BAN/Assert.h

@@ -1,11 +1,33 @@
 #pragma once
 
+#include <BAN/Traits.h>
+
 #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_BIN_OP(lhs, rhs, name, op)														\
+		do {																						\
+			auto&& _lhs = lhs;																		\
+			auto&& _rhs = rhs;																		\
+			if (!(_lhs op _rhs))																	\
+					Kernel::panic(name "(" #lhs ", " #rhs ") ({} " #op " {}) failed", _lhs, _rhs);	\
+		} while (false)
+
+	#define ASSERT_LT(lhs, rhs)		__ASSERT_BIN_OP(lhs, rhs, "ASSERT_LT",	<)
+	#define ASSERT_LTE(lhs, rhs)	__ASSERT_BIN_OP(lhs, rhs, "ASSERT_LTE",	<=)
+	#define ASSERT_GT(lhs, rhs)		__ASSERT_BIN_OP(lhs, rhs, "ASSERT_GT",	>)
+	#define ASSERT_GTE(lhs, rhs)	__ASSERT_BIN_OP(lhs, rhs, "ASSERT_GTE",	>=)
+	#define ASSERT_EQ(lhs, rhs)		__ASSERT_BIN_OP(lhs, rhs, "ASSERT_EQ",	==)
+	#define ASSERT_NEQ(lhs, rhs)	__ASSERT_BIN_OP(lhs, rhs, "ASSERT_NEQ",	!=)
 	#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() do { assert(false && "ASSERT_NOT_REACHED() failed"); __builtin_unreachable(); } while (false)
-#endif
+#endif

BAN/include/BAN/String.h

@@ -82,17 +82,21 @@ namespace BAN
 	private:
 		struct SSOStorage
 		{
-			char storage[sso_capacity + 1] {};
+			char data[sso_capacity + 1] {};
 		};
 		struct GeneralStorage
 		{
-			size_type capacity { 0 };
-			char* data;
+			size_type capacity	{ 0 };
+			char* data			{ nullptr };
 		};
 
 	private:
-		Variant<SSOStorage, GeneralStorage>	m_storage	{ SSOStorage() };
-		size_type							m_size		{ 0 };
+		union {
+			SSOStorage sso_storage;
+			GeneralStorage general_storage;
+		} m_storage										{ .sso_storage = SSOStorage() };
+		size_type m_size	: sizeof(size_type) * 8 - 1	{ 0 };
+		size_type m_has_sso	: 1							{ true };
 	};
 
 	template<typename... Args>

CMakeLists.txt

@@ -10,7 +10,6 @@ add_compile_definitions(__enable_sse=0)
 project(banan-os CXX C ASM)
 
 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)
@@ -24,8 +23,7 @@ add_subdirectory(userspace)
 
 add_custom_target(sysroot
 	COMMAND ${CMAKE_COMMAND} -E make_directory ${BANAN_SYSROOT}
-	COMMAND cd ${BANAN_SYSROOT} && sudo tar xf ${BANAN_BASE_SYSROOT}
-	USES_TERMINAL
+	COMMAND cd ${BANAN_SYSROOT} && tar xf ${BANAN_BASE_SYSROOT}
 )
 
 add_custom_target(headers
@@ -36,6 +34,7 @@ add_custom_target(headers
 )
 
 add_custom_target(install-sysroot
+	COMMAND cd ${BANAN_SYSROOT} && tar cf ${BANAN_SYSROOT_TAR} *
 	DEPENDS kernel-install
 	DEPENDS ban-install
 	DEPENDS libc-install

LibELF/CMakeLists.txt

@@ -3,9 +3,8 @@ 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}/
+	COMMAND ${CMAKE_COMMAND} -E copy_directory_if_different ${CMAKE_CURRENT_SOURCE_DIR}/include/ ${BANAN_INCLUDE}/
 	DEPENDS sysroot
-	USES_TERMINAL
 )
 
 add_custom_target(libelf-install

LibELF/LibELF/LoadableELF.cpp

@@ -1,4 +1,5 @@
 #include <BAN/ScopeGuard.h>
+#include <kernel/CriticalScope.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/LockGuard.h>
 #include <LibELF/LoadableELF.h>
@@ -226,7 +227,8 @@ namespace LibELF
 					if (paddr == 0)
 						return BAN::Error::from_errno(ENOMEM);
 
-					m_page_table.map_page_at(paddr, vaddr, flags);
+					// Temporarily map page as RW so kernel can write to it
+					m_page_table.map_page_at(paddr, vaddr, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
 					m_physical_page_count++;
 
 					memset((void*)vaddr, 0x00, PAGE_SIZE);
@@ -245,6 +247,9 @@ namespace LibELF
 						TRY(m_inode->read(program_header.p_offset + file_offset, { (uint8_t*)vaddr + vaddr_offset, bytes }));
 					}
 
+					// Map page with the correct flags
+					m_page_table.map_page_at(paddr, vaddr, flags);
+
 					return {};
 				}
 				default:
@@ -302,9 +307,12 @@ namespace LibELF
 						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);
+						{
+							CriticalScope _;
+							PageTable::map_fast_page(paddr);
+							memcpy(PageTable::fast_page_as_ptr(), (void*)(start + i * PAGE_SIZE), PAGE_SIZE);
+							PageTable::unmap_fast_page();
+						}
 
 						new_page_table.map_page_at(paddr, start + i * PAGE_SIZE, flags);
 						elf->m_physical_page_count++;

README.md

@@ -2,7 +2,7 @@
 
 # banan-os
 
-This is my hobby operating system written in C++. Currently supports only x86_64 architecture. We have a ext2 filesystem, basic ramfs, IDE disk drivers in ATA PIO mode, ATA AHCI drivers, userspace processes, executable loading from ELF format, linear VBE graphics and multithreaded processing on single core.
+This is my hobby operating system written in C++. Currently supports only x86\_64 architecture. We have a ext2 filesystem, basic ramfs, IDE disk drivers in ATA PIO mode, ATA AHCI drivers, 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)
 
@@ -20,7 +20,7 @@ To build the toolchain for this os. You can run the following command.
 ./script/build.sh toolchain
 ```
 
-To build the os itself you can run one of the following commands. You will need root access since the sysroot has "proper" permissions.
+To build the os itself you can run one of the following commands. You will need root access for disk image creation/modification.
 ```sh
 ./script/build.sh qemu
 ./script/build.sh qemu-nographic
@@ -39,8 +39,6 @@ If you have corrupted your disk image or want to create new one, you can either
 ./script/build.sh image-full
 ```
 
-> ***NOTE*** ```ninja clean``` has to be ran with root permissions, since it deletes from the banan-so sysroot.
-
 If you feel like ```./script/build.sh``` is too verbose, there exists a symlink _bos_ in this projects root directory. All build commands can be used with ```./bos args...``` instead.
 
 I have also created shell completion script for zsh. You can either copy the file in _script/shell-completion/zsh/\_bos_ to _/usr/share/zsh/site-functions/_ or add the _script/shell-completion/zsh_ to your fpath in _.zshrc_.

kernel/CMakeLists.txt

@@ -36,7 +36,6 @@ set(KERNEL_SOURCES
 	kernel/kernel.cpp
 	kernel/Memory/DMARegion.cpp
 	kernel/Memory/FileBackedRegion.cpp
-	kernel/Memory/GeneralAllocator.cpp
 	kernel/Memory/Heap.cpp
 	kernel/Memory/kmalloc.cpp
 	kernel/Memory/MemoryBackedRegion.cpp
@@ -148,6 +147,9 @@ target_compile_options(kernel PUBLIC $<$<COMPILE_LANGUAGE:CXX>:-Wno-literal-suff
 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)
 
+# This might not work with other toolchains
+target_compile_options(kernel PUBLIC $<$<COMPILE_LANGUAGE:CXX>:-Wno-invalid-offsetof>)
+
 if(ENABLE_KERNEL_UBSAN)
 	target_compile_options(kernel PUBLIC -fsanitize=undefined)
 endif()
@@ -162,28 +164,15 @@ 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}/
+	COMMAND ${CMAKE_COMMAND} -E copy_directory_if_different ${CMAKE_CURRENT_SOURCE_DIR}/include/ ${BANAN_INCLUDE}/
+	COMMAND ${CMAKE_COMMAND} -E copy_directory_if_different ${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
+	COMMAND ${CMAKE_COMMAND} -E copy ${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)
@@ -193,8 +182,8 @@ 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} .
+	COMMAND ${CMAKE_COMMAND} -E copy ${CRTBEGIN} .
+	COMMAND ${CMAKE_COMMAND} -E copy ${CRTEND} .
 )
 
 #add_custom_command(

kernel/arch/x86_64/IDT.cpp

@@ -181,14 +181,20 @@ namespace Kernel::IDT
 			{
 				// Check if stack is OOB
 				auto& stack = Thread::current().stack();
-				if (interrupt_stack.rsp < stack.vaddr())
+				auto& istack = Thread::current().interrupt_stack();
+				if (stack.vaddr() < interrupt_stack.rsp && interrupt_stack.rsp <= stack.vaddr() + stack.size())
+					; // using normal stack
+				else if (istack.vaddr() < interrupt_stack.rsp && interrupt_stack.rsp <= istack.vaddr() + istack.size())
+					; // using interrupt stack
+				else
 				{
-					derrorln("Stack overflow");
-					goto done;
-				}
-				if (interrupt_stack.rsp >= stack.vaddr() + stack.size())
-				{
-					derrorln("Stack underflow");
+					derrorln("Stack pointer out of bounds!");
+					derrorln("rsp {H}, stack {H}->{H}, istack {H}->{H}",
+						interrupt_stack.rsp,
+						stack.vaddr(), stack.vaddr() + stack.size(),
+						istack.vaddr(), istack.vaddr() + istack.size()
+					);
+					Thread::current().handle_signal(SIGKILL);
 					goto done;
 				}
 
@@ -207,7 +213,7 @@ namespace Kernel::IDT
 					if (result.is_error())
 					{
 						dwarnln("Demand paging: {}", result.error());
-						Thread::current().handle_signal(SIGTERM);
+						Thread::current().handle_signal(SIGKILL);
 						goto done;
 					}
 				}

kernel/arch/x86_64/PageTable.cpp

@@ -1,6 +1,6 @@
-#include <BAN/Errors.h>
 #include <kernel/Arch.h>
 #include <kernel/CPUID.h>
+#include <kernel/InterruptController.h>
 #include <kernel/LockGuard.h>
 #include <kernel/Memory/kmalloc.h>
 #include <kernel/Memory/PageTable.h>
@@ -92,6 +92,13 @@ namespace Kernel
 			s_has_pge = true;
 		}
 
+		// enable write protect to kernel
+		asm volatile(
+			"movq %cr0, %rax;"
+			"orq $0x10000, %rax;"
+			"movq %rax, %cr0;"
+		);
+
 		ASSERT(s_kernel == nullptr);
 		s_kernel = new PageTable();
 		ASSERT(s_kernel);
@@ -136,8 +143,16 @@ namespace Kernel
 		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);
+		prepare_fast_page();
+
+		// Map (phys_kernel_start -> phys_kernel_end) to (virt_kernel_start -> virt_kernel_end)
+		ASSERT((vaddr_t)g_kernel_start % PAGE_SIZE == 0);
+		map_range_at(
+			V2P(g_kernel_start),
+			(vaddr_t)g_kernel_start,
+			g_kernel_end - g_kernel_start,
+			Flags::ReadWrite | Flags::Present
+		);
 
 		// Map executable kernel memory as executable
 		map_range_at(
@@ -172,6 +187,76 @@ namespace Kernel
 		g_multiboot2_info = (multiboot2_info_t*)(multiboot2_vaddr + ((vaddr_t)g_multiboot2_info % PAGE_SIZE));
 	}
 
+	void PageTable::prepare_fast_page()
+	{
+		constexpr vaddr_t uc_vaddr = uncanonicalize(fast_page());
+		constexpr uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
+		constexpr uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
+		constexpr uint64_t pde   = (uc_vaddr >> 21) & 0x1FF;
+		constexpr uint64_t pte   = (uc_vaddr >> 12) & 0x1FF;
+
+		uint64_t* pml4 = (uint64_t*)P2V(m_highest_paging_struct);
+		ASSERT(!(pml4[pml4e] & Flags::Present));
+		pml4[pml4e] = V2P(allocate_zeroed_page_aligned_page()) | Flags::ReadWrite | Flags::Present;
+
+		uint64_t* pdpt = (uint64_t*)P2V(pml4[pml4e] & PAGE_ADDR_MASK);
+		ASSERT(!(pdpt[pdpte] & Flags::Present));
+		pdpt[pdpte] = V2P(allocate_zeroed_page_aligned_page()) | Flags::ReadWrite | Flags::Present;
+
+		uint64_t* pd = (uint64_t*)P2V(pdpt[pdpte] & PAGE_ADDR_MASK);
+		ASSERT(!(pd[pde] & Flags::Present));
+		pd[pde] = V2P(allocate_zeroed_page_aligned_page()) | Flags::ReadWrite | Flags::Present;
+
+		uint64_t* pt = (uint64_t*)P2V(pd[pde] & PAGE_ADDR_MASK);
+		ASSERT(!(pt[pte] & Flags::Present));
+		pt[pte] = V2P(allocate_zeroed_page_aligned_page());
+	}
+
+	void PageTable::map_fast_page(paddr_t paddr)
+	{
+		ASSERT(s_kernel);
+		ASSERT_NEQ(paddr, 0);
+		ASSERT(!interrupts_enabled());
+
+		constexpr vaddr_t uc_vaddr = uncanonicalize(fast_page());
+		constexpr uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
+		constexpr uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
+		constexpr uint64_t pde   = (uc_vaddr >> 21) & 0x1FF;
+		constexpr uint64_t pte   = (uc_vaddr >> 12) & 0x1FF;
+
+		uint64_t* pml4 = (uint64_t*)P2V(s_kernel->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);
+
+		ASSERT(!(pt[pte] & Flags::Present));
+		pt[pte] = paddr | Flags::ReadWrite | Flags::Present;
+
+		invalidate(fast_page());
+	}
+
+	void PageTable::unmap_fast_page()
+	{
+		ASSERT(s_kernel);
+		ASSERT(!interrupts_enabled());
+
+		constexpr vaddr_t uc_vaddr = uncanonicalize(fast_page());
+		constexpr uint64_t pml4e = (uc_vaddr >> 39) & 0x1FF;
+		constexpr uint64_t pdpte = (uc_vaddr >> 30) & 0x1FF;
+		constexpr uint64_t pde   = (uc_vaddr >> 21) & 0x1FF;
+		constexpr uint64_t pte   = (uc_vaddr >> 12) & 0x1FF;
+
+		uint64_t* pml4 = (uint64_t*)P2V(s_kernel->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);
+
+		ASSERT(pt[pte] & Flags::Present);
+		pt[pte] = 0;
+
+		invalidate(fast_page());
+	}
+
 	BAN::ErrorOr<PageTable*> PageTable::create_userspace()
 	{
 		LockGuard _(s_kernel->m_lock);
@@ -233,13 +318,16 @@ namespace Kernel
 	void PageTable::invalidate(vaddr_t vaddr)
 	{
 		ASSERT(vaddr % PAGE_SIZE == 0);
-		if (this == s_current)
-			asm volatile("invlpg (%0)" :: "r"(vaddr) : "memory");
+		asm volatile("invlpg (%0)" :: "r"(vaddr) : "memory");
 	}
 
 	void PageTable::unmap_page(vaddr_t vaddr)
 	{
-		if (vaddr && (vaddr >= KERNEL_OFFSET) != (this == s_kernel))
+		ASSERT(vaddr);
+		ASSERT(vaddr != fast_page());
+		if (vaddr >= KERNEL_OFFSET)
+			ASSERT_GTE(vaddr, (vaddr_t)g_kernel_start);
+		if ((vaddr >= KERNEL_OFFSET) != (this == s_kernel))
 			Kernel::panic("unmapping {8H}, kernel: {}", vaddr, this == s_kernel);
 
 		ASSERT(is_canonical(vaddr));
@@ -281,7 +369,11 @@ namespace Kernel
 
 	void PageTable::map_page_at(paddr_t paddr, vaddr_t vaddr, flags_t flags)
 	{
-		if (vaddr && (vaddr >= KERNEL_OFFSET) != (this == s_kernel))
+		ASSERT(vaddr);
+		ASSERT(vaddr != fast_page());
+		if (vaddr >= KERNEL_OFFSET)
+			ASSERT_GTE(vaddr, (vaddr_t)g_kernel_start);
+		if ((vaddr >= KERNEL_OFFSET) != (this == s_kernel))
 			Kernel::panic("mapping {8H} to {8H}, kernel: {}", paddr, vaddr, this == s_kernel);
 
 		ASSERT(is_canonical(vaddr));
@@ -348,12 +440,11 @@ namespace Kernel
 	{
 		ASSERT(is_canonical(vaddr));
 
+		ASSERT(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;
+		size_t page_count = range_page_count(vaddr, size);
 		
 		LockGuard _(m_lock);
 		for (size_t page = 0; page < page_count; page++)
@@ -430,6 +521,8 @@ namespace Kernel
 
 	vaddr_t PageTable::reserve_free_page(vaddr_t first_address, vaddr_t last_address)
 	{
+		if (first_address >= KERNEL_OFFSET && first_address < (vaddr_t)g_kernel_end)
+			first_address = (vaddr_t)g_kernel_end;
 		if (size_t rem = first_address % PAGE_SIZE)
 			first_address += PAGE_SIZE - rem;
 		if (size_t rem = last_address % PAGE_SIZE)
@@ -487,8 +580,9 @@ namespace Kernel
 							vaddr |= (uint64_t)pdpte << 30;
 							vaddr |= (uint64_t)pde   << 21;
 							vaddr |= (uint64_t)pte   << 12;
+							vaddr = canonicalize(vaddr);
 							ASSERT(reserve_page(vaddr));
-							return canonicalize(vaddr);
+							return vaddr;
 						}
 					}
 				}
@@ -512,6 +606,8 @@ namespace Kernel
 
 	vaddr_t PageTable::reserve_free_contiguous_pages(size_t page_count, vaddr_t first_address, vaddr_t last_address)
 	{
+		if (first_address >= KERNEL_OFFSET && first_address < (vaddr_t)g_kernel_start)
+			first_address = (vaddr_t)g_kernel_start;
 		if (size_t rem = first_address % PAGE_SIZE)
 			first_address += PAGE_SIZE - rem;
 		if (size_t rem = last_address % PAGE_SIZE)

kernel/include/kernel/Memory/FileBackedRegion.h

@@ -38,6 +38,7 @@ namespace Kernel
 		BAN::RefPtr<Inode> m_inode;
 		const off_t m_offset;
 
+		// FIXME: is this even synchronized?
 		BAN::RefPtr<SharedFileData> m_shared_data;
 	};
 

kernel/include/kernel/Memory/GeneralAllocator.h

@@ -1,46 +0,0 @@
-#pragma once
-
-#include <BAN/LinkedList.h>
-#include <BAN/Optional.h>
-#include <BAN/UniqPtr.h>
-#include <kernel/Memory/Heap.h>
-#include <kernel/Memory/PageTable.h>
-
-namespace Kernel
-{
-
-	class GeneralAllocator
-	{
-		BAN_NON_COPYABLE(GeneralAllocator);
-		BAN_NON_MOVABLE(GeneralAllocator);
-
-	public:
-		static BAN::ErrorOr<BAN::UniqPtr<GeneralAllocator>> create(PageTable&, vaddr_t first_vaddr);
-		~GeneralAllocator();
-
-		BAN::ErrorOr<BAN::UniqPtr<GeneralAllocator>> clone(PageTable&);
-
-		BAN::Optional<paddr_t> paddr_of(vaddr_t);
-
-		vaddr_t allocate(size_t);
-		bool deallocate(vaddr_t);
-
-	private:
-		GeneralAllocator(PageTable&, vaddr_t first_vaddr);
-
-	private:
-		struct Allocation
-		{
-			vaddr_t address { 0 };
-			BAN::Vector<paddr_t> pages;
-
-			bool contains(vaddr_t);
-		};
-
-	private:
-		PageTable& m_page_table;
-		BAN::LinkedList<Allocation> m_allocations;
-		const vaddr_t m_first_vaddr;
-	};
-
-}

kernel/include/kernel/Memory/PageTable.h

@@ -29,6 +29,24 @@ namespace Kernel
 		static PageTable& kernel();
 		static PageTable& current();
 
+		static void map_fast_page(paddr_t);
+		static void unmap_fast_page();
+		static constexpr vaddr_t fast_page() { return KERNEL_OFFSET; }
+
+		// FIXME: implement sized checks, return span, etc
+		static void* fast_page_as_ptr(size_t offset = 0)
+		{
+			ASSERT(offset <= PAGE_SIZE);
+			return reinterpret_cast<void*>(fast_page() + offset);
+		}
+
+		template<typename T>
+		static T& fast_page_as(size_t offset = 0)
+		{
+			ASSERT(offset + sizeof(T) <= PAGE_SIZE);
+			return *reinterpret_cast<T*>(fast_page() + offset);
+		}
+
 		static bool is_valid_pointer(uintptr_t);
 
 		static BAN::ErrorOr<PageTable*> create_userspace();
@@ -64,7 +82,8 @@ namespace Kernel
 		uint64_t get_page_data(vaddr_t) const;
 		void initialize_kernel();
 		void map_kernel_memory();
-		void invalidate(vaddr_t);
+		void prepare_fast_page();		
+		static void invalidate(vaddr_t);
 
 	private:
 		paddr_t						m_highest_paging_struct { 0 };

kernel/include/kernel/Panic.h

@@ -11,11 +11,11 @@ namespace Kernel::detail
 
 	template<typename... Args>
 	__attribute__((__noreturn__))
-	static void panic_impl(const char* file, int line, const char* message, Args... args)
+	static void panic_impl(const char* file, int line, const char* message, Args&&... args)
 	{
 		asm volatile("cli");
 		derrorln("Kernel panic at {}:{}", file, line);
-		derrorln(message, args...);
+		derrorln(message, BAN::forward<Args>(args)...);
 		if (!g_paniced)
 		{
 			g_paniced = true;

kernel/include/kernel/Thread.h

@@ -71,6 +71,7 @@ namespace Kernel
 		vaddr_t stack_base() const { return m_stack->vaddr(); }
 		size_t stack_size() const { return m_stack->size(); }
 		VirtualRange& stack() { return *m_stack; }
+		VirtualRange& interrupt_stack() { return *m_interrupt_stack; }
 
 		vaddr_t interrupt_stack_base() const { return m_interrupt_stack ? m_interrupt_stack->vaddr() : 0; }
 		size_t interrupt_stack_size() const { return m_interrupt_stack ? m_interrupt_stack->size() : 0; }

kernel/kernel/ACPI.cpp

@@ -117,33 +117,33 @@ namespace Kernel
 
 		if (rsdp->revision >= 2)
 		{
-			PageTable::kernel().map_page_at(rsdp->xsdt_address & PAGE_ADDR_MASK, 0, PageTable::Flags::Present);
-			const XSDT* xsdt = (const XSDT*)(rsdp->xsdt_address % PAGE_SIZE);
-			BAN::ScopeGuard _([xsdt] { PageTable::kernel().unmap_page(0); });
+			PageTable::map_fast_page(rsdp->xsdt_address & PAGE_ADDR_MASK);
+			auto& xsdt = PageTable::fast_page_as<const XSDT>(rsdp->xsdt_address % PAGE_SIZE);
+			BAN::ScopeGuard _([] { PageTable::unmap_fast_page(); });
 
-			if (memcmp(xsdt->signature, "XSDT", 4) != 0)
+			if (memcmp(xsdt.signature, "XSDT", 4) != 0)
 				return BAN::Error::from_error_code(ErrorCode::ACPI_RootInvalid);
-			if (!is_valid_std_header(xsdt))
+			if (!is_valid_std_header(&xsdt))
 				return BAN::Error::from_error_code(ErrorCode::ACPI_RootInvalid);
 
-			m_header_table_paddr = (paddr_t)xsdt->entries + (rsdp->rsdt_address & PAGE_ADDR_MASK);
+			m_header_table_paddr = rsdp->xsdt_address + offsetof(XSDT, entries);
 			m_entry_size = 8;
-			root_entry_count = (xsdt->length - sizeof(SDTHeader)) / 8;
+			root_entry_count = (xsdt.length - sizeof(SDTHeader)) / 8;
 		}
 		else
 		{
-			PageTable::kernel().map_page_at(rsdp->rsdt_address & PAGE_ADDR_MASK, 0, PageTable::Flags::Present);
-			const RSDT* rsdt = (const RSDT*)((vaddr_t)rsdp->rsdt_address % PAGE_SIZE);
-			BAN::ScopeGuard _([rsdt] { PageTable::kernel().unmap_page(0); });
+			PageTable::map_fast_page(rsdp->rsdt_address & PAGE_ADDR_MASK);
+			auto& rsdt = PageTable::fast_page_as<const RSDT>(rsdp->rsdt_address % PAGE_SIZE);
+			BAN::ScopeGuard _([] { PageTable::unmap_fast_page(); });
 
-			if (memcmp(rsdt->signature, "RSDT", 4) != 0)
+			if (memcmp(rsdt.signature, "RSDT", 4) != 0)
 				return BAN::Error::from_error_code(ErrorCode::ACPI_RootInvalid);
-			if (!is_valid_std_header(rsdt))
+			if (!is_valid_std_header(&rsdt))
 				return BAN::Error::from_error_code(ErrorCode::ACPI_RootInvalid);
 
-			m_header_table_paddr = (paddr_t)rsdt->entries + (rsdp->rsdt_address & PAGE_ADDR_MASK);
+			m_header_table_paddr = rsdp->rsdt_address + offsetof(RSDT, entries);
 			m_entry_size = 4;
-			root_entry_count = (rsdt->length - sizeof(SDTHeader)) / 4;
+			root_entry_count = (rsdt.length - sizeof(SDTHeader)) / 4;
 		}
 
 		size_t needed_pages = range_page_count(m_header_table_paddr, root_entry_count * m_entry_size);
@@ -162,9 +162,9 @@ namespace Kernel
 		auto map_header =
 			[](paddr_t header_paddr) -> vaddr_t
 			{
-				PageTable::kernel().map_page_at(header_paddr & PAGE_ADDR_MASK, 0, PageTable::Flags::Present);
-				size_t header_length = ((SDTHeader*)(header_paddr % PAGE_SIZE))->length;
-				PageTable::kernel().unmap_page(0);
+				PageTable::map_fast_page(header_paddr & PAGE_ADDR_MASK);
+				size_t header_length = PageTable::fast_page_as<SDTHeader>(header_paddr % PAGE_SIZE).length;
+				PageTable::unmap_fast_page();
 
 				size_t needed_pages = range_page_count(header_paddr, header_length);
 				vaddr_t page_vaddr = PageTable::kernel().reserve_free_contiguous_pages(needed_pages, KERNEL_OFFSET);
@@ -211,7 +211,10 @@ namespace Kernel
 			if (memcmp(header->signature, "FACP", 4) == 0)
 			{
 				auto* fadt = (FADT*)header;
-				paddr_t dsdt_paddr = fadt->x_dsdt;
+
+				paddr_t dsdt_paddr = 0;
+				if (fadt->length > offsetof(FADT, x_dsdt))
+					dsdt_paddr = fadt->x_dsdt;
 				if (dsdt_paddr == 0 || !PageTable::is_valid_pointer(dsdt_paddr))
 					dsdt_paddr = fadt->dsdt;
 

kernel/kernel/FS/Ext2/Inode.cpp

@@ -274,6 +274,9 @@ namespace Kernel
 	{
 		ASSERT(m_inode.links_count == 0);
 
+		if (mode().iflnk() && (size_t)size() < sizeof(m_inode.block))
+			goto done;
+
 		// cleanup direct blocks
 		for (uint32_t i = 0; i < 12; i++)
 			if (m_inode.block[i])
@@ -287,6 +290,7 @@ namespace Kernel
 		if (m_inode.block[14])
 			cleanup_indirect_block(m_inode.block[14], 3);
 
+done:
 		// mark blocks as deleted
 		memset(m_inode.block, 0x00, sizeof(m_inode.block));
 
@@ -759,7 +763,7 @@ needs_new_block:
 
 		if (data_block_index < indices_per_fs_block * indices_per_fs_block)
 			return TRY(allocate_new_block_to_indirect_block(m_inode.block[13], data_block_index, 2));
-		data_block_index -= indices_per_fs_block;
+		data_block_index -= indices_per_fs_block * indices_per_fs_block;
 
 		if (data_block_index < indices_per_fs_block * indices_per_fs_block * indices_per_fs_block)
 			return TRY(allocate_new_block_to_indirect_block(m_inode.block[14], data_block_index, 3));

kernel/kernel/Memory/FileBackedRegion.cpp

@@ -1,3 +1,4 @@
+#include <kernel/CriticalScope.h>
 #include <kernel/LockGuard.h>
 #include <kernel/Memory/FileBackedRegion.h>
 #include <kernel/Memory/Heap.h>
@@ -71,13 +72,10 @@ namespace Kernel
 				continue;
 			
 			{
-				auto& page_table = PageTable::current();
-				LockGuard _(page_table);
-				ASSERT(page_table.is_page_free(0));
-
-				page_table.map_page_at(pages[i], 0, PageTable::Flags::Present);
-				memcpy(page_buffer, (void*)0, PAGE_SIZE);
-				page_table.unmap_page(0);
+				CriticalScope _;
+				PageTable::map_fast_page(pages[i]);
+				memcpy(page_buffer, PageTable::fast_page_as_ptr(), PAGE_SIZE);
+				PageTable::unmap_fast_page();
 			}
 
 			if (auto ret = inode->write(i * PAGE_SIZE, BAN::ConstByteSpan::from(page_buffer)); ret.is_error())
@@ -100,28 +98,15 @@ namespace Kernel
 			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, m_flags);
+
+			// Temporarily force mapping to be writable so kernel can write to it
+			m_page_table.map_page_at(paddr, vaddr, m_flags | PageTable::Flags::ReadWrite);
 
 			size_t file_offset = m_offset + (vaddr - m_vaddr);
 			size_t bytes = BAN::Math::min<size_t>(m_size - file_offset, PAGE_SIZE);
 
-			BAN::ErrorOr<size_t> read_ret = 0;
-
-			// Zero out the new page
-			if (&PageTable::current() == &m_page_table)
-				read_ret = m_inode->read(file_offset, BAN::ByteSpan((uint8_t*)vaddr, bytes));
-			else
-			{
-				auto& page_table = PageTable::current();
-
-				LockGuard _(page_table);
-				ASSERT(page_table.is_page_free(0));
-
-				page_table.map_page_at(paddr, 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-				read_ret = m_inode->read(file_offset, BAN::ByteSpan((uint8_t*)0, bytes));
-				memset((void*)0, 0x00, PAGE_SIZE);
-				page_table.unmap_page(0);
-			}
+			ASSERT_EQ(&PageTable::current(), &m_page_table);
+			auto read_ret = m_inode->read(file_offset, BAN::ByteSpan((uint8_t*)vaddr, bytes));
 
 			if (read_ret.is_error())
 			{
@@ -137,6 +122,10 @@ namespace Kernel
 				m_page_table.unmap_page(vaddr);
 				return BAN::Error::from_errno(EIO);
 			}
+
+			// Disable writable if not wanted
+			if (!(m_flags & PageTable::Flags::ReadWrite))
+				m_page_table.map_page_at(paddr, vaddr, m_flags);
 		}
 		else if	(m_type == Type::SHARED)
 		{
@@ -158,15 +147,10 @@ namespace Kernel
 
 				TRY(m_inode->read(offset, BAN::ByteSpan(m_shared_data->page_buffer, bytes)));
 
-				auto& page_table = PageTable::current();
-
-				// TODO: check if this can cause deadlock?
-				LockGuard page_table_lock(page_table);
-				ASSERT(page_table.is_page_free(0));
-
-				page_table.map_page_at(pages[page_index], 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-				memcpy((void*)0, m_shared_data->page_buffer, PAGE_SIZE);
-				page_table.unmap_page(0);
+				CriticalScope _;
+				PageTable::map_fast_page(pages[page_index]);
+				memcpy(PageTable::fast_page_as_ptr(), m_shared_data->page_buffer, PAGE_SIZE);
+				PageTable::unmap_fast_page();
 			}
 
 			paddr_t paddr = pages[page_index];

kernel/kernel/Memory/GeneralAllocator.cpp

@@ -1,145 +0,0 @@
-#include <kernel/Memory/GeneralAllocator.h>
-
-namespace Kernel
-{
-
-	BAN::ErrorOr<BAN::UniqPtr<GeneralAllocator>> GeneralAllocator::create(PageTable& page_table, vaddr_t first_vaddr)
-	{
-		auto* allocator = new GeneralAllocator(page_table, first_vaddr);
-		if (allocator == nullptr)
-			return BAN::Error::from_errno(ENOMEM);
-		return BAN::UniqPtr<GeneralAllocator>::adopt(allocator);
-	}
-
-	GeneralAllocator::GeneralAllocator(PageTable& page_table, vaddr_t first_vaddr)
-		: m_page_table(page_table)
-		, m_first_vaddr(first_vaddr)
-	{ }
-
-	GeneralAllocator::~GeneralAllocator()
-	{
-		while (!m_allocations.empty())
-			deallocate(m_allocations.front().address);
-	}
-
-	vaddr_t GeneralAllocator::allocate(size_t bytes)
-	{
-		size_t needed_pages = BAN::Math::div_round_up<size_t>(bytes, PAGE_SIZE);
-
-		Allocation allocation;
-		if (allocation.pages.resize(needed_pages, 0).is_error())
-			return 0;
-
-		for (size_t i = 0; i < needed_pages; i++)
-		{
-			paddr_t paddr = Heap::get().take_free_page();
-			if (paddr == 0)
-			{
-				for (size_t j = 0; j < i; j++)
-					Heap::get().release_page(allocation.pages[j]);
-				return 0;
-			}
-			allocation.pages[i] = paddr;
-		}
-
-		m_page_table.lock();
-
-		allocation.address = m_page_table.reserve_free_contiguous_pages(needed_pages, m_first_vaddr);
-		ASSERT(allocation.address);
-
-		for (size_t i = 0; i < needed_pages; i++)
-		{
-			vaddr_t vaddr = allocation.address + i * PAGE_SIZE;
-			m_page_table.map_page_at(allocation.pages[i], vaddr, PageTable::Flags::UserSupervisor | PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-		}
-
-		if (&m_page_table == &PageTable::current())
-			m_page_table.load();
-
-		m_page_table.unlock();
-
-		MUST(m_allocations.push_back(BAN::move(allocation)));
-		return allocation.address;
-	}
-
-	bool GeneralAllocator::deallocate(vaddr_t address)
-	{
-		for (auto it = m_allocations.begin(); it != m_allocations.end(); it++)
-		{
-			if (it->address != address)
-				continue;
-			
-			m_page_table.unmap_range(it->address, it->pages.size() * PAGE_SIZE);
-			for (auto paddr : it->pages)
-				Heap::get().release_page(paddr);
-
-			m_allocations.remove(it);
-
-			return true;
-		}
-
-		return false;
-	}
-
-	BAN::ErrorOr<BAN::UniqPtr<GeneralAllocator>> GeneralAllocator::clone(PageTable& new_page_table)
-	{
-		auto allocator = TRY(GeneralAllocator::create(new_page_table, m_first_vaddr));
-
-		m_page_table.lock();
-
-		ASSERT(m_page_table.is_page_free(0));
-
-		for (auto& allocation : m_allocations)
-		{
-			Allocation new_allocation;
-			ASSERT(new_page_table.is_range_free(allocation.address, allocation.pages.size() * PAGE_SIZE));
-
-			new_allocation.address = allocation.address;
-			MUST(new_allocation.pages.reserve(allocation.pages.size()));
-
-			PageTable::flags_t flags = m_page_table.get_page_flags(allocation.address);
-			for (size_t i = 0; i < allocation.pages.size(); i++)
-			{
-				paddr_t paddr = Heap::get().take_free_page();
-				ASSERT(paddr);
-
-				vaddr_t vaddr = allocation.address + i * PAGE_SIZE;
-
-				MUST(new_allocation.pages.push_back(paddr));
-				new_page_table.map_page_at(paddr, vaddr, flags);
-
-				m_page_table.map_page_at(paddr, 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-				memcpy((void*)0, (void*)vaddr, PAGE_SIZE);
-			}
-
-			MUST(allocator->m_allocations.push_back(BAN::move(new_allocation)));
-		}
-		m_page_table.unmap_page(0);
-
-		m_page_table.unlock();
-
-		return allocator;
-	}
-
-	BAN::Optional<paddr_t> GeneralAllocator::paddr_of(vaddr_t vaddr)
-	{
-		for (auto& allocation : m_allocations)
-		{
-			if (!allocation.contains(vaddr))
-				continue;
-			
-			size_t offset = vaddr - allocation.address;
-			size_t page_index = offset / PAGE_SIZE;
-			size_t page_offset = offset % PAGE_SIZE;
-			return allocation.pages[page_index] + page_offset;
-		}
-
-		return {};
-	}
-
-	bool GeneralAllocator::Allocation::contains(vaddr_t vaddr)
-	{
-		return this->address <= vaddr && vaddr < this->address + this->pages.size() * PAGE_SIZE;
-	}
-
-}

kernel/kernel/Memory/MemoryBackedRegion.cpp

@@ -1,3 +1,4 @@
+#include <kernel/CriticalScope.h>
 #include <kernel/LockGuard.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/Memory/MemoryBackedRegion.h>
@@ -60,12 +61,10 @@ namespace Kernel
 			memset((void*)vaddr, 0x00, PAGE_SIZE);
 		else
 		{
-			LockGuard _(PageTable::current());
-			ASSERT(PageTable::current().is_page_free(0));
-
-			PageTable::current().map_page_at(paddr, 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-			memset((void*)0, 0x00, PAGE_SIZE);
-			PageTable::current().unmap_page(0);
+			CriticalScope _;
+			PageTable::map_fast_page(paddr);
+			memset(PageTable::fast_page_as_ptr(), 0x00, PAGE_SIZE);
+			PageTable::unmap_fast_page();
 		}
 
 		return true;
@@ -105,15 +104,10 @@ namespace Kernel
 				memcpy((void*)write_vaddr, (void*)(buffer + written), bytes);
 			else
 			{
-				paddr_t paddr = m_page_table.physical_address_of(write_vaddr & PAGE_ADDR_MASK);
-				ASSERT(paddr);
-
-				LockGuard _(PageTable::current());
-				ASSERT(PageTable::current().is_page_free(0));
-
-				PageTable::current().map_page_at(paddr, 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-				memcpy((void*)page_offset, (void*)(buffer + written), bytes);
-				PageTable::current().unmap_page(0);
+				CriticalScope _;
+				PageTable::map_fast_page(m_page_table.physical_address_of(write_vaddr & PAGE_ADDR_MASK));
+				memcpy(PageTable::fast_page_as_ptr(page_offset), (void*)(buffer + written), bytes);
+				PageTable::unmap_fast_page();
 			}
 
 			written += bytes;

kernel/kernel/Memory/VirtualRange.cpp

@@ -1,3 +1,4 @@
+#include <kernel/CriticalScope.h>
 #include <kernel/LockGuard.h>
 #include <kernel/Memory/Heap.h>
 #include <kernel/Memory/VirtualRange.h>
@@ -124,7 +125,6 @@ namespace Kernel
 		auto result = TRY(create_to_vaddr(page_table, vaddr(), size(), flags(), m_preallocated));
 
 		LockGuard _(m_page_table);
-		ASSERT(m_page_table.is_page_free(0));
 		for (size_t offset = 0; offset < size(); offset += PAGE_SIZE)
 		{
 			if (!m_preallocated && m_page_table.physical_address_of(vaddr() + offset))
@@ -134,10 +134,12 @@ namespace Kernel
 					return BAN::Error::from_errno(ENOMEM);
 				result->m_page_table.map_page_at(paddr, vaddr() + offset, m_flags);					
 			}
-			m_page_table.map_page_at(result->m_page_table.physical_address_of(vaddr() + offset), 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-			memcpy((void*)0, (void*)(vaddr() + offset), PAGE_SIZE);
+
+			CriticalScope _;
+			PageTable::map_fast_page(result->m_page_table.physical_address_of(vaddr() + offset));
+			memcpy(PageTable::fast_page_as_ptr(), (void*)(vaddr() + offset), PAGE_SIZE);
+			PageTable::unmap_fast_page();
 		}
-		m_page_table.unmap_page(0);
 
 		return result;
 	}
@@ -172,14 +174,13 @@ namespace Kernel
 			return;
 		}
 
-		LockGuard _(page_table);
-		ASSERT(page_table.is_page_free(0));
 		for (size_t offset = 0; offset < size(); offset += PAGE_SIZE)
 		{
-			page_table.map_page_at(m_page_table.physical_address_of(vaddr() + offset), 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-			memset((void*)0, 0, PAGE_SIZE);
+			CriticalScope _;
+			PageTable::map_fast_page(m_page_table.physical_address_of(vaddr() + offset));
+			memset(PageTable::fast_page_as_ptr(), 0x00, PAGE_SIZE);
+			PageTable::unmap_fast_page();
 		}
-		page_table.unmap_page(0);
 	}
 
 	void VirtualRange::copy_from(size_t offset, const uint8_t* buffer, size_t bytes)
@@ -187,47 +188,34 @@ namespace Kernel
 		if (bytes == 0)
 			return;
 
-		// NOTE: Handling overflow
-		ASSERT(offset <= size());
-		ASSERT(bytes <= size());
-		ASSERT(offset + bytes <= size());
+		// Verify no overflow
+		ASSERT_LTE(bytes, size());
+		ASSERT_LTE(offset, size());
+		ASSERT_LTE(offset, size() - bytes);
 
-		PageTable& page_table = PageTable::current();
-
-		if (m_kmalloc || &page_table == &m_page_table)
+		if (m_kmalloc || &PageTable::current() == &m_page_table)
 		{
 			memcpy((void*)(vaddr() + offset), buffer, bytes);
 			return;
 		}
 
-		LockGuard _(page_table);
-		ASSERT(page_table.is_page_free(0));
-
-		size_t off = offset % PAGE_SIZE;
-		size_t i = offset / PAGE_SIZE;
-
-		// NOTE: we map the first page separately since it needs extra calculations
-		page_table.map_page_at(m_page_table.physical_address_of(vaddr() + i * PAGE_SIZE), 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-
-		memcpy((void*)off, buffer, PAGE_SIZE - off);
-
-		buffer += PAGE_SIZE - off;
-		bytes  -= PAGE_SIZE - off;
-		i++;
+		size_t page_offset = offset % PAGE_SIZE;
+		size_t page_index = offset / PAGE_SIZE;
 
 		while (bytes > 0)
 		{
-			size_t len = BAN::Math::min<size_t>(PAGE_SIZE, bytes);
+			{
+				CriticalScope _;
+				PageTable::map_fast_page(m_page_table.physical_address_of(vaddr() + page_index * PAGE_SIZE));
+				memcpy(PageTable::fast_page_as_ptr(page_offset), buffer, PAGE_SIZE - page_offset);
+				PageTable::unmap_fast_page();
+			}
 
-			page_table.map_page_at(m_page_table.physical_address_of(vaddr() + i * PAGE_SIZE), 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-
-			memcpy((void*)0, buffer, len);
-
-			buffer += len;
-			bytes  -= len;
-			i++;
+			buffer += PAGE_SIZE - page_offset;
+			bytes  -= PAGE_SIZE - page_offset;
+			page_offset = 0;
+			page_index++;
 		}
-		page_table.unmap_page(0);
 	}
 
 }

kernel/kernel/Memory/kmalloc.cpp

@@ -1,7 +1,6 @@
 #include <BAN/Errors.h>
 #include <kernel/CriticalScope.h>
 #include <kernel/kprint.h>
-#include <kernel/Memory/GeneralAllocator.h>
 #include <kernel/Memory/kmalloc.h>
 
 #include <kernel/Thread.h>

kernel/kernel/Storage/DiskCache.cpp

@@ -47,9 +47,9 @@ namespace Kernel
 				continue;
 
 			CriticalScope _;
-			page_table.map_page_at(cache.paddr, 0, PageTable::Flags::Present);
-			memcpy(buffer.data(), (void*)(page_cache_offset * m_sector_size), m_sector_size);
-			page_table.unmap_page(0);
+			PageTable::map_fast_page(cache.paddr);
+			memcpy(buffer.data(), PageTable::fast_page_as_ptr(page_cache_offset * m_sector_size), m_sector_size);
+			PageTable::unmap_fast_page();
 
 			return true;
 		}
@@ -82,9 +82,9 @@ namespace Kernel
 			
 			{
 				CriticalScope _;
-				page_table.map_page_at(cache.paddr, 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-				memcpy((void*)(page_cache_offset * m_sector_size), buffer.data(), m_sector_size);
-				page_table.unmap_page(0);
+				PageTable::map_fast_page(cache.paddr);
+				memcpy(PageTable::fast_page_as_ptr(page_cache_offset * m_sector_size), buffer.data(), m_sector_size);
+				PageTable::unmap_fast_page();
 			}
 
 			cache.sector_mask |= 1 << page_cache_offset;
@@ -113,9 +113,9 @@ namespace Kernel
 
 		{
 			CriticalScope _;
-			page_table.map_page_at(cache.paddr, 0, PageTable::Flags::ReadWrite | PageTable::Flags::Present);
-			memcpy((void*)(page_cache_offset * m_sector_size), buffer.data(), m_sector_size);
-			page_table.unmap_page(0);
+			PageTable::map_fast_page(cache.paddr);
+			memcpy(PageTable::fast_page_as_ptr(page_cache_offset * m_sector_size), buffer.data(), m_sector_size);
+			PageTable::unmap_fast_page();
 		}
 
 		return {};
@@ -123,21 +123,16 @@ namespace Kernel
 
 	BAN::ErrorOr<void> DiskCache::sync()
 	{
-		ASSERT(&PageTable::current() == &PageTable::kernel());
-		auto& page_table = PageTable::kernel();
-
 		for (auto& cache : m_cache)
 		{
 			if (cache.dirty_mask == 0)
 				continue;
 
 			{
-				LockGuard _(page_table);
-				ASSERT(page_table.is_page_free(0));
-
-				page_table.map_page_at(cache.paddr, 0, PageTable::Flags::Present);
-				memcpy(m_sync_cache.data(), (void*)0, PAGE_SIZE);
-				page_table.unmap_page(0);
+				CriticalScope _;
+				PageTable::map_fast_page(cache.paddr);
+				memcpy(m_sync_cache.data(), PageTable::fast_page_as_ptr(), PAGE_SIZE);
+				PageTable::unmap_fast_page();
 			}
 
 			uint8_t sector_start = 0;

kernel/kernel/kernel.cpp

@@ -79,9 +79,6 @@ static void parse_command_line()
 	}
 }
 
-extern "C" uint8_t g_userspace_start[];
-extern "C" uint8_t g_userspace_end[];
-
 TerminalDriver* g_terminal_driver = nullptr;
 
 static void init2(void*);

libc/CMakeLists.txt

@@ -26,21 +26,32 @@ set(LIBC_SOURCES
 )
 
 add_custom_target(libc-headers
-	COMMAND sudo rsync -a ${CMAKE_CURRENT_SOURCE_DIR}/include/ ${BANAN_INCLUDE}/
+	COMMAND ${CMAKE_COMMAND} -E copy_directory_if_different ${CMAKE_CURRENT_SOURCE_DIR}/include/ ${BANAN_INCLUDE}/
 	DEPENDS sysroot
-	USES_TERMINAL
+)
+
+add_custom_target(crtx
+	COMMAND ${CMAKE_C_COMPILER} -c ${CMAKE_CURRENT_SOURCE_DIR}/arch/${BANAN_ARCH}/crt0.S -o crt0.o
+	COMMAND ${CMAKE_C_COMPILER} -c ${CMAKE_CURRENT_SOURCE_DIR}/arch/${BANAN_ARCH}/crti.S -o crti.o
+	COMMAND ${CMAKE_C_COMPILER} -c ${CMAKE_CURRENT_SOURCE_DIR}/arch/${BANAN_ARCH}/crtn.S -o crtn.o
+)
+
+add_custom_target(crtx-install
+	COMMAND ${CMAKE_COMMAND} -E copy crt0.o ${BANAN_LIB}/
+	COMMAND ${CMAKE_COMMAND} -E copy crti.o ${BANAN_LIB}/
+	COMMAND ${CMAKE_COMMAND} -E copy crtn.o ${BANAN_LIB}/
+	DEPENDS crtx
 )
 
 add_library(libc ${LIBC_SOURCES})
-add_dependencies(libc headers crt0)
+add_dependencies(libc headers crtx-install)
 
 target_compile_options(libc PRIVATE -g -Wstack-usage=512)
 
 add_custom_target(libc-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/libc.a ${BANAN_LIB}/
+	COMMAND ${CMAKE_COMMAND} -E copy_if_different ${CMAKE_CURRENT_BINARY_DIR}/libc.a ${BANAN_LIB}/
 	DEPENDS libc
 	BYPRODUCTS ${BANAN_LIB}/libc.a
-	USES_TERMINAL
 )
 
 set(CMAKE_STATIC_LIBRARY_PREFIX "")

libc/arch/x86_64/crt0.S

@@ -8,19 +8,19 @@ _start:
 	pushq %rbp # rbp=0
 	movq %rsp, %rbp
 
-	# We need those in a moment when we call main.
+	# Save argc, argv, environ
 	pushq %rdx
 	pushq %rsi
 	pushq %rdi
 
-	# Prepare signals, memory allocation, stdio and such.
+	# Prepare malloc, environment
 	movq %rdx, %rdi
 	call _init_libc
 
-	# Run the global constructors.
+	# Call global constructos
 	call _init
 
-	# Restore argc and argv.
+	# Restore argc, argv, environ
 	popq %rdi
 	popq %rsi
 	popq %rdx
@@ -28,7 +28,8 @@ _start:
 	# Run main
 	call main
 
-	# Terminate the process with the exit code.
+	# Cleanly exit the process
 	movl %eax, %edi
 	call exit
+
 .size _start, . - _start

libc/arch/x86_64/crti.S

@@ -0,0 +1,16 @@
+/* x86-64 crti.s */
+.section .init
+.global _init
+.type _init, @function
+_init:
+	pushq %rbp
+	movq %rsp, %rbp
+	/* gcc will nicely put the contents of crtbegin.o's .init section here. */
+
+.section .fini
+.global _fini
+.type _fini, @function
+_fini:
+	pushq %rbp
+	movq %rsp, %rbp
+	/* gcc will nicely put the contents of crtbegin.o's .fini section here. */

libc/arch/x86_64/crtn.S

@@ -0,0 +1,10 @@
+/* x86-64 crtn.s */
+.section .init
+	/* gcc will nicely put the contents of crtend.o's .init section here. */
+	popq %rbp
+	ret
+
+.section .fini
+	/* gcc will nicely put the contents of crtend.o's .fini section here. */
+	popq %rbp
+	ret

libc/icxxabi.cpp

@@ -1,35 +1,37 @@
+#include <icxxabi.h>
+
 #define ATEXIT_MAX_FUNCS 128
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-typedef unsigned uarch_t;
-
 struct atexit_func_entry_t
 {
-	/*
-	* Each member is at least 4 bytes large. Such that each entry is 12bytes.
-	* 128 * 12 = 1.5KB exact.
-	**/
-	void (*destructor_func)(void *);
-	void *obj_ptr;
-	void *dso_handle;
+	void (*destructor)(void*);
+	void* data;
+	void* dso_handle;
 };
 
-atexit_func_entry_t __atexit_funcs[ATEXIT_MAX_FUNCS];
-uarch_t __atexit_func_count = 0;
+static atexit_func_entry_t __atexit_funcs[ATEXIT_MAX_FUNCS];
+static int __atexit_func_count = 0;
 
-int __cxa_atexit(void (*f)(void *), void *objptr, void *dso)
+int __cxa_atexit(void (*func)(void*), void* data, void* dso_handle)
 {
-	if (__atexit_func_count >= ATEXIT_MAX_FUNCS) {return -1;};
-	__atexit_funcs[__atexit_func_count].destructor_func = f;
-	__atexit_funcs[__atexit_func_count].obj_ptr = objptr;
-	__atexit_funcs[__atexit_func_count].dso_handle = dso;
+	if (__atexit_func_count >= ATEXIT_MAX_FUNCS)
+		return -1;;
+	__atexit_funcs[__atexit_func_count].destructor = func;
+	__atexit_funcs[__atexit_func_count].data = data;
+	__atexit_funcs[__atexit_func_count].dso_handle = dso_handle;
 	__atexit_func_count++;
-	return 0; /*I would prefer if functions returned 1 on success, but the ABI says...*/
+	return 0;
 };
 
-#ifdef __cplusplus
-};
-#endif
+void __cxa_finalize(void* func)
+{
+	for (int i = __atexit_func_count - 1; i >= 0; i--)
+	{
+		if (func && func != __atexit_funcs[i].destructor)
+			continue;
+		if (__atexit_funcs[i].destructor == nullptr)
+			continue;
+		__atexit_funcs[i].destructor(__atexit_funcs[i].data);
+		__atexit_funcs[i].destructor = nullptr;
+	}
+}

libc/include/icxxabi.h

@@ -0,0 +1,10 @@
+#pragma once
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+int __cxa_atexit(void (*func)(void*), void* data, void* dso_handle);
+void __cxa_finalize(void* func);
+
+__END_DECLS

libc/stdlib.cpp

@@ -7,6 +7,8 @@
 #include <sys/syscall.h>
 #include <unistd.h>
 
+#include <icxxabi.h>
+
 extern "C" char** environ;
 
 extern "C" void _fini();
@@ -21,6 +23,7 @@ void abort(void)
 void exit(int status)
 {
 	fflush(nullptr);
+	__cxa_finalize(nullptr);
 	_fini();
 	_exit(status);
 	ASSERT_NOT_REACHED();

script/build.sh

@@ -4,6 +4,12 @@ set -e
 export BANAN_SCRIPT_DIR=$(dirname $(realpath $0))
 source $BANAN_SCRIPT_DIR/config.sh
 
+FAKEROOT_FILE="$BANAN_BUILD_DIR/fakeroot-context"
+
+run_fakeroot() {
+	fakeroot -i $FAKEROOT_FILE -s $FAKEROOT_FILE -- /bin/bash -c '$@' bash $@
+}
+
 make_build_dir () {
 	mkdir -p $BANAN_BUILD_DIR
 	cd $BANAN_BUILD_DIR
@@ -19,7 +25,7 @@ build_target () {
 		exit 1
 	fi
 	cd $BANAN_BUILD_DIR
-	ninja $1
+	run_fakeroot ninja $1
 }
 
 build_toolchain () {
@@ -39,11 +45,7 @@ build_toolchain () {
 
 create_image () {
 	build_target install-sysroot
-	if [[ "$1" == "full" ]]; then
-		$BANAN_SCRIPT_DIR/image-full.sh
-	else
-		$BANAN_SCRIPT_DIR/image.sh
-	fi
+	$BANAN_SCRIPT_DIR/image.sh "$1"
 }
 
 run_qemu () {
@@ -56,7 +58,7 @@ run_bochs () {
 	$BANAN_SCRIPT_DIR/bochs.sh $@
 }
 
-if [[ "$(uname)" == "Linux" ]]; then
+if [[ -c /dev/kvm ]]; then
 	QEMU_ACCEL="-accel kvm"
 fi
 

script/config.sh

@@ -18,6 +18,7 @@ export BANAN_TOOLCHAIN_TRIPLE_PREFIX=$BANAN_ARCH-banan_os
 export BANAN_BUILD_DIR=$BANAN_ROOT_DIR/build
 
 export BANAN_SYSROOT=$BANAN_BUILD_DIR/sysroot
+export BANAN_SYSROOT_TAR=$BANAN_SYSROOT.tar
 
 export BANAN_DISK_IMAGE_PATH=$BANAN_BUILD_DIR/banan-os.img
 

script/image-create.sh

@@ -72,7 +72,7 @@ sudo partprobe $LOOP_DEV
 PARTITION1=${LOOP_DEV}p1
 PARTITION2=${LOOP_DEV}p2
 
-sudo mkfs.ext2 -d $BANAN_SYSROOT -b 1024 -q $PARTITION2
+sudo mkfs.ext2 -b 1024 -q $PARTITION2
 
 if [[ "$BANAN_UEFI_BOOT" == "1" ]]; then
 	sudo mkfs.fat $PARTITION1 > /dev/null

script/image.sh

@@ -1,44 +1,38 @@
 #!/bin/bash
 
-if [[ -z $BANAN_ROOT_DIR ]]; then
-	echo  "You must set the BANAN_ROOT_DIR environment variable" >&2
-	exit 1
-fi
-
 if [[ -z $BANAN_DISK_IMAGE_PATH ]]; then
 	echo  "You must set the BANAN_DISK_IMAGE_PATH environment variable" >&2
 	exit 1
 fi
 
-if [[ -z $BANAN_SYSROOT ]]; then
-	echo  "You must set the BANAN_SYSROOT environment variable" >&2
+if [[ -z $BANAN_SYSROOT_TAR ]]; then
+	echo  "You must set the BANAN_SYSROOT_TAR environment variable" >&2
 	exit 1
 fi
 
-if [[ ! -f $BANAN_DISK_IMAGE_PATH ]]; then
-	$BANAN_SCRIPT_DIR/image-full.sh
-	exit 0
+if [[ "$1" == "full" ]] || [[ ! -f $BANAN_DISK_IMAGE_PATH ]]; then
+	$BANAN_SCRIPT_DIR/image-create.sh
+else
+	fdisk -l $BANAN_DISK_IMAGE_PATH | grep -q 'EFI System'; IMAGE_IS_UEFI=$?
+	[[ $BANAN_UEFI_BOOT == 1 ]]; CREATE_IS_UEFI=$?
+
+	if [[ $IMAGE_IS_UEFI -ne $CREATE_IS_UEFI ]]; then
+		echo Converting disk image to/from UEFI
+		$BANAN_SCRIPT_DIR/image-create.sh
+	fi
 fi
 
-fdisk -l $BANAN_DISK_IMAGE_PATH | grep -q 'EFI System'; IMAGE_IS_UEFI=$?
-[[ $BANAN_UEFI_BOOT == 1 ]]; CREATE_IS_UEFI=$?
-
-if [[ $IMAGE_IS_UEFI -ne $CREATE_IS_UEFI ]]; then
-	echo Converting disk image to/from UEFI
-	$BANAN_SCRIPT_DIR/image-full.sh
-	exit 0
-fi
-
-MOUNT_DIR=/mnt
-
-LOOP_DEV=$(sudo losetup -f --show $BANAN_DISK_IMAGE_PATH)
+LOOP_DEV=$(sudo losetup --show -f "$BANAN_DISK_IMAGE_PATH")
 sudo partprobe $LOOP_DEV
 
-ROOT_PARTITON=${LOOP_DEV}p2
+ROOT_PARTITION=${LOOP_DEV}p2
+MOUNT_DIR=/mnt
 
-sudo mount $ROOT_PARTITON $MOUNT_DIR
+sudo mount $ROOT_PARTITION $MOUNT_DIR
 
-sudo rsync -a ${BANAN_SYSROOT}/* ${MOUNT_DIR}/
+cd $MOUNT_DIR
+sudo tar xf $BANAN_SYSROOT_TAR
+cd
 
 sudo umount $MOUNT_DIR
 

toolchain/Toolchain.txt

@@ -1,9 +1,19 @@
 if (NOT DEFINED ENV{BANAN_ARCH})
 	message(FATAL_ERROR "environment variable BANAN_ARCH not defined")
 endif ()
-
 set(BANAN_ARCH $ENV{BANAN_ARCH})
 
+if (NOT DEFINED ENV{BANAN_SYSROOT})
+	message(FATAL_ERROR "environment variable BANAN_SYSROOT not defined")
+endif ()
+set(BANAN_SYSROOT $ENV{BANAN_SYSROOT})
+
+if (NOT DEFINED ENV{BANAN_SYSROOT_TAR})
+	message(FATAL_ERROR "environment variable BANAN_SYSROOT_TAR not defined")
+endif ()
+set(BANAN_SYSROOT_TAR $ENV{BANAN_SYSROOT_TAR})
+
+
 set(TOOLCHAIN_PREFIX ${CMAKE_SOURCE_DIR}/toolchain/local)
 
 set(CMAKE_SYSTEM_NAME banan-os)

toolchain/build.sh

@@ -2,7 +2,13 @@
 set -e
 
 BINUTILS_VERSION="binutils-2.39"
+BINUTILS_GIT="https://sourceware.org/git/binutils-gdb.git"
+BINUTILS_BRANCH="binutils-2_39"
+
 GCC_VERSION="gcc-12.2.0"
+GCC_GIT="https://gcc.gnu.org/git/gcc.git"
+GCC_BRANCH="releases/$GCC_VERSION"
+
 GRUB_VERSION="grub-2.06"
 
 if [[ -z $BANAN_SYSROOT ]]; then
@@ -51,22 +57,20 @@ build_binutils () {
 
 	cd $BANAN_BUILD_DIR/toolchain
 
-	if [ ! -f ${BINUTILS_VERSION}.tar.xz ]; then
-		wget https://ftp.gnu.org/gnu/binutils/${BINUTILS_VERSION}.tar.xz
-	fi
-
 	if [ ! -d $BINUTILS_VERSION ]; then
-		tar xvf ${BINUTILS_VERSION}.tar.xz
-		patch -s -p0 < $BANAN_TOOLCHAIN_DIR/${BINUTILS_VERSION}.patch
+		git clone --single-branch --branch $BINUTILS_BRANCH $BINUTILS_GIT $BINUTILS_VERSION
+		cd $BINUTILS_VERSION
+		git am $BANAN_TOOLCHAIN_DIR/$BINUTILS_VERSION.patch
 	fi
 
-	cd $BINUTILS_VERSION
+	cd $BANAN_BUILD_DIR/toolchain/$BINUTILS_VERSION
 	enter_clean_build
 
 	../configure \
 		--target="$BANAN_TOOLCHAIN_TRIPLE_PREFIX" \
 		--prefix="$BANAN_TOOLCHAIN_PREFIX" \
 		--with-sysroot="$BANAN_SYSROOT" \
+		--disable-initfini-array \
 		--disable-nls \
 		--disable-werror
 
@@ -79,22 +83,20 @@ build_gcc () {
 
 	cd $BANAN_BUILD_DIR/toolchain
 
-	if [ ! -f ${GCC_VERSION}.tar.xz ]; then
-		wget https://ftp.gnu.org/gnu/gcc/${GCC_VERSION}/${GCC_VERSION}.tar.xz
-	fi
-
 	if [ ! -d $GCC_VERSION ]; then
-		tar xvf ${GCC_VERSION}.tar.xz
-		patch -s -p0 < $BANAN_TOOLCHAIN_DIR/${GCC_VERSION}.patch
+		git clone --single-branch --branch $GCC_BRANCH $GCC_GIT $GCC_VERSION
+		cd $GCC_VERSION
+		git am $BANAN_TOOLCHAIN_DIR/$GCC_VERSION.patch
 	fi
 
-	cd ${GCC_VERSION}
+	cd $BANAN_BUILD_DIR/toolchain/$GCC_VERSION
 	enter_clean_build
 
 	../configure \
 		--target="$BANAN_TOOLCHAIN_TRIPLE_PREFIX" \
 		--prefix="$BANAN_TOOLCHAIN_PREFIX" \
 		--with-sysroot="$BANAN_SYSROOT" \
+		--disable-initfini-array \
 		--disable-nls \
 		--enable-languages=c,c++
 
@@ -159,6 +161,9 @@ sudo rsync -a $BANAN_ROOT_DIR/libc/include/ $BANAN_SYSROOT/usr/include/
 
 mkdir -p $BANAN_BUILD_DIR/toolchain
 
+# Cleanup all old files from toolchain prefix
+rm -rf $BANAN_TOOLCHAIN_PREFIX
+
 build_binutils
 build_gcc
 build_grub

userspace/CMakeLists.txt

@@ -23,6 +23,7 @@ set(USERSPACE_PROJECTS
 	sync
 	tee
 	test
+	test-globals
 	touch
 	u8sum
 	whoami

userspace/Shell/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(Shell PUBLIC -O2 -g)
 target_link_libraries(Shell PUBLIC libc ban)
 
 add_custom_target(Shell-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/Shell ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/Shell ${BANAN_BIN}/
 	DEPENDS Shell
-	USES_TERMINAL
 )

userspace/cat-mmap/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(cat-mmap PUBLIC -O2 -g)
 target_link_libraries(cat-mmap PUBLIC libc)
 
 add_custom_target(cat-mmap-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/cat-mmap ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/cat-mmap ${BANAN_BIN}/
 	DEPENDS cat-mmap
-	USES_TERMINAL
 )

userspace/cat/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(cat PUBLIC -O2 -g)
 target_link_libraries(cat PUBLIC libc)
 
 add_custom_target(cat-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/cat ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/cat ${BANAN_BIN}/
 	DEPENDS cat
-	USES_TERMINAL
 )

userspace/chmod/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(chmod PUBLIC -O2 -g)
 target_link_libraries(chmod PUBLIC libc)
 
 add_custom_target(chmod-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/chmod ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/chmod ${BANAN_BIN}/
 	DEPENDS chmod
-	USES_TERMINAL
 )

userspace/cp/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(cp PUBLIC -O2 -g)
 target_link_libraries(cp PUBLIC libc ban)
 
 add_custom_target(cp-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/cp ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/cp ${BANAN_BIN}/
 	DEPENDS cp
-	USES_TERMINAL
 )

userspace/create_program.sh

@@ -20,9 +20,8 @@ target_compile_options($PROGRAM_NAME PUBLIC -O2 -g)
 target_link_libraries($PROGRAM_NAME PUBLIC libc)
 
 add_custom_target($PROGRAM_NAME-install
-	COMMAND sudo cp \${CMAKE_CURRENT_BINARY_DIR}/$PROGRAM_NAME \${BANAN_BIN}/
+	COMMAND \${CMAKE_COMMAND} -E copy \${CMAKE_CURRENT_BINARY_DIR}/$PROGRAM_NAME \${BANAN_BIN}/
 	DEPENDS $PROGRAM_NAME
-	USES_TERMINAL
 )
 EOF
 

userspace/dd/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(dd PUBLIC -O2 -g)
 target_link_libraries(dd PUBLIC libc)
 
 add_custom_target(dd-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/dd ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/dd ${BANAN_BIN}/
 	DEPENDS dd
-	USES_TERMINAL
 )

userspace/echo/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(echo PUBLIC -O2 -g)
 target_link_libraries(echo PUBLIC libc)
 
 add_custom_target(echo-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/echo ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/echo ${BANAN_BIN}/
 	DEPENDS echo
-	USES_TERMINAL
 )

userspace/id/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(id PUBLIC -O2 -g)
 target_link_libraries(id PUBLIC libc ban)
 
 add_custom_target(id-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/id ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/id ${BANAN_BIN}/
 	DEPENDS id
-	USES_TERMINAL
 )

userspace/init/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(init PUBLIC -O2 -g)
 target_link_libraries(init PUBLIC libc ban)
 
 add_custom_target(init-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/init ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/init ${BANAN_BIN}/
 	DEPENDS init
-	USES_TERMINAL
 )

userspace/ls/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(ls PUBLIC -O2 -g)
 target_link_libraries(ls PUBLIC libc)
 
 add_custom_target(ls-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/ls ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/ls ${BANAN_BIN}/
 	DEPENDS ls
-	USES_TERMINAL
 )

userspace/meminfo/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(meminfo PUBLIC -O2 -g)
 target_link_libraries(meminfo PUBLIC libc)
 
 add_custom_target(meminfo-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/meminfo ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/meminfo ${BANAN_BIN}/
 	DEPENDS meminfo
-	USES_TERMINAL
 )

userspace/mkdir/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(mkdir PUBLIC -O2 -g)
 target_link_libraries(mkdir PUBLIC libc)
 
 add_custom_target(mkdir-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/mkdir ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/mkdir ${BANAN_BIN}/
 	DEPENDS mkdir
-	USES_TERMINAL
 )

userspace/mmap-shared-test/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(mmap-shared-test PUBLIC -O2 -g)
 target_link_libraries(mmap-shared-test PUBLIC libc)
 
 add_custom_target(mmap-shared-test-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/mmap-shared-test ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/mmap-shared-test ${BANAN_BIN}/
 	DEPENDS mmap-shared-test
-	USES_TERMINAL
 )

userspace/poweroff/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(poweroff PUBLIC -O2 -g)
 target_link_libraries(poweroff PUBLIC libc)
 
 add_custom_target(poweroff-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/poweroff ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/poweroff ${BANAN_BIN}/
 	DEPENDS poweroff
-	USES_TERMINAL
 )

userspace/rm/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(rm PUBLIC -O2 -g)
 target_link_libraries(rm PUBLIC libc ban)
 
 add_custom_target(rm-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/rm ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/rm ${BANAN_BIN}/
 	DEPENDS rm
-	USES_TERMINAL
 )

userspace/snake/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(snake PUBLIC -O2 -g)
 target_link_libraries(snake PUBLIC libc)
 
 add_custom_target(snake-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/snake ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/snake ${BANAN_BIN}/
 	DEPENDS snake
-	USES_TERMINAL
 )

userspace/stat/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(stat PUBLIC -O2 -g)
 target_link_libraries(stat PUBLIC libc ban)
 
 add_custom_target(stat-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/stat ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/stat ${BANAN_BIN}/
 	DEPENDS stat
-	USES_TERMINAL
 )

userspace/sync/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(sync PUBLIC -O2 -g)
 target_link_libraries(sync PUBLIC libc)
 
 add_custom_target(sync-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/sync ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/sync ${BANAN_BIN}/
 	DEPENDS sync
-	USES_TERMINAL
 )

userspace/tee/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(tee PUBLIC -O2 -g)
 target_link_libraries(tee PUBLIC libc)
 
 add_custom_target(tee-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/tee ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/tee ${BANAN_BIN}/
 	DEPENDS tee
-	USES_TERMINAL
 )

userspace/test-globals/CMakeLists.txt

@@ -0,0 +1,16 @@
+cmake_minimum_required(VERSION 3.26)
+
+project(test-globals CXX)
+
+set(SOURCES
+	main.cpp
+)
+
+add_executable(test-globals ${SOURCES})
+target_compile_options(test-globals PUBLIC -O2 -g)
+target_link_libraries(test-globals PUBLIC libc)
+
+add_custom_target(test-globals-install
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/test-globals ${BANAN_BIN}/
+	DEPENDS test-globals
+)

userspace/test-globals/main.cpp

@@ -0,0 +1,14 @@
+#include <stdio.h>
+
+struct foo_t
+{
+	foo_t() { printf("global constructor works\n"); }
+	~foo_t() { printf("global destructor works\n"); }
+};
+
+foo_t foo;
+
+int main()
+{
+
+}

userspace/test/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(test PUBLIC -O2 -g)
 target_link_libraries(test PUBLIC libc)
 
 add_custom_target(test-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/test ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/test ${BANAN_BIN}/
 	DEPENDS test
-	USES_TERMINAL
 )

userspace/touch/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(touch PUBLIC -O2 -g)
 target_link_libraries(touch PUBLIC libc)
 
 add_custom_target(touch-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/touch ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/touch ${BANAN_BIN}/
 	DEPENDS touch
-	USES_TERMINAL
 )

userspace/u8sum/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(u8sum PUBLIC -O2 -g)
 target_link_libraries(u8sum PUBLIC libc)
 
 add_custom_target(u8sum-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/u8sum ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/u8sum ${BANAN_BIN}/
 	DEPENDS u8sum
-	USES_TERMINAL
 )

userspace/whoami/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(whoami PUBLIC -O2 -g)
 target_link_libraries(whoami PUBLIC libc ban)
 
 add_custom_target(whoami-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/whoami ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/whoami ${BANAN_BIN}/
 	DEPENDS whoami
-	USES_TERMINAL
 )

userspace/yes/CMakeLists.txt

@@ -11,7 +11,6 @@ target_compile_options(yes PUBLIC -O2 -g)
 target_link_libraries(yes PUBLIC libc)
 
 add_custom_target(yes-install
-	COMMAND sudo cp ${CMAKE_CURRENT_BINARY_DIR}/yes ${BANAN_BIN}/
+	COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_BINARY_DIR}/yes ${BANAN_BIN}/
 	DEPENDS yes
-	USES_TERMINAL
 )