Kernel: Add basic concept of Processes

We now create Shell as a process that has its own threads

BAN/include/BAN/Memory.h

@@ -62,12 +62,21 @@ namespace BAN
 	{
 	public:
 		RefPtr() = default;
+		RefPtr(T* pointer)
+		{
+			m_pointer = pointer;
+			if (m_pointer)
+				m_pointer->ref();
+		}
+
 		~RefPtr() { clear(); }
 
 		template<typename U>
 		static RefPtr adopt(U* pointer)
 		{
-			return RefPtr(pointer);
+			RefPtr ptr;
+			ptr.m_pointer = pointer;
+			return ptr;
 		}
 
 		template<typename... Args>
@@ -76,7 +85,7 @@ namespace BAN
 			T* pointer = new T(forward<Args>(args)...);
 			if (pointer == nullptr)
 				return Error::from_errno(ENOMEM);
-			return RefPtr(pointer);
+			return adopt(pointer);
 		}
 
 		RefPtr(const RefPtr& other) { *this = other; }
@@ -118,11 +127,6 @@ namespace BAN
 			m_pointer = nullptr;
 		}
 
-	private:
-		RefPtr(T* pointer)
-			: m_pointer(pointer)
-		{}
-
 	private:
 		T* m_pointer = nullptr;
 	};

kernel/Makefile

@@ -50,6 +50,7 @@ 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/include/kernel/Process.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include <BAN/String.h>
+#include <BAN/Vector.h>
+#include <kernel/Thread.h>
+
+namespace Kernel
+{
+
+	class Process : BAN::RefCounted<Process>
+	{
+		BAN_NON_COPYABLE(Process);
+		BAN_NON_MOVABLE(Process);
+
+	public:
+		using entry_t = Thread::entry_t;
+
+	public:
+		static BAN::ErrorOr<BAN::RefPtr<Process>> create_kernel(entry_t, void*);
+		~Process() {}
+
+		BAN::ErrorOr<void> add_thread(entry_t, void*);
+		void on_thread_exit(Thread&);
+
+		pid_t pid() const { return m_pid; }
+
+		static BAN::RefPtr<Process> current() { return Thread::current()->process(); }
+
+	private:
+		Process(pid_t pid) : m_pid(pid) {}
+
+	private:
+		pid_t m_pid = 0;
+		BAN::String m_working_directory;
+		BAN::Vector<BAN::RefPtr<Thread>> m_threads;
+
+		friend class BAN::RefPtr<Process>;
+	};
+
+}

kernel/include/kernel/Scheduler.h

@@ -21,11 +21,11 @@ namespace Kernel
 		void set_current_thread_sleeping(uint64_t);
 		[[noreturn]] void set_current_thread_done();
 
+		BAN::RefPtr<Thread> current_thread();
+
 	private:
 		Scheduler() = default;
 
-		BAN::RefPtr<Thread> current_thread();
-
 		void wake_threads();
 		[[nodiscard]] bool save_current_thread();
 		void remove_and_advance_current_thread();

kernel/include/kernel/Thread.h

@@ -3,19 +3,23 @@
 #include <BAN/Function.h>
 #include <BAN/NoCopyMove.h>
 
+#include <sys/types.h>
+
 namespace Kernel
 {
 
+	class Process;
+
 	class Thread : public BAN::RefCounted<Thread>
 	{
 	public:
 		using entry_t = void(*)(void*);
 
 	public:
-		static BAN::ErrorOr<BAN::RefPtr<Thread>> create(entry_t, void* = nullptr);
+		static BAN::ErrorOr<BAN::RefPtr<Thread>> create(entry_t, void* = nullptr, BAN::RefPtr<Process> = nullptr);
 		~Thread();
 
-		uint32_t tid() const { return m_tid; }
+		pid_t tid() const { return m_tid; }
 
 		void set_rsp(uintptr_t rsp) { m_rsp = rsp; }
 		void set_rip(uintptr_t rip) { m_rip = rip; }
@@ -25,8 +29,12 @@ namespace Kernel
 		void set_started() { m_started = true; }
 		bool started() const { return m_started; }
 
+		static BAN::RefPtr<Thread> current() ;
+		BAN::RefPtr<Process> process();
+
 	private:
-		Thread();
+		Thread(pid_t tid, BAN::RefPtr<Process>);
+
 		BAN::ErrorOr<void> initialize(entry_t, void*);
 		void on_exit();
 		
@@ -34,8 +42,9 @@ namespace Kernel
 		void*		m_stack_base	= nullptr;
 		uintptr_t	m_rip			= 0;
 		uintptr_t	m_rsp			= 0;
-		const uint32_t	m_tid			= 0;
+		const pid_t	m_tid			= 0;
 		bool		m_started		= false;
+		BAN::RefPtr<Process> m_process;
 
 		friend class BAN::RefPtr<Thread>;
 	};

kernel/kernel/Process.cpp

@@ -0,0 +1,37 @@
+#include <BAN/StringView.h>
+#include <kernel/Process.h>
+#include <kernel/Scheduler.h>
+
+namespace Kernel
+{
+
+	BAN::ErrorOr<BAN::RefPtr<Process>> Process::create_kernel(entry_t entry, void* data)
+	{
+		static pid_t next_pid = 1;
+		auto process = TRY(BAN::RefPtr<Process>::create(next_pid++));
+		TRY(process->add_thread(entry, data));
+		TRY(process->m_working_directory.append("/"sv));
+		return process;
+	}
+
+	BAN::ErrorOr<void> Process::add_thread(entry_t entry, void* data)
+	{
+		auto thread = TRY(Thread::create(entry, data, this));
+		TRY(m_threads.push_back(thread));
+		if (auto res = Scheduler::get().add_thread(thread); res.is_error())
+		{
+			m_threads.pop_back();
+			return res;
+		}
+
+		dprintln("add thread {} to process {}", thread->tid(), pid());
+
+		return {};
+	}
+
+	void Process::on_thread_exit(Thread& thread)
+	{
+		dprintln("thread {} exited from process", thread.tid(), pid());
+	}
+
+}

kernel/kernel/Scheduler.cpp

@@ -2,6 +2,7 @@
 #include <kernel/Attributes.h>
 #include <kernel/CriticalScope.h>
 #include <kernel/InterruptController.h>
+#include <kernel/Process.h>
 #include <kernel/Scheduler.h>
 
 #if 1

kernel/kernel/Shell.cpp

@@ -5,8 +5,8 @@
 #include <kernel/Input.h>
 #include <kernel/IO.h>
 #include <kernel/PIT.h>
+#include <kernel/Process.h>
 #include <kernel/RTC.h>
-#include <kernel/Scheduler.h>
 #include <kernel/Shell.h>
 
 #include <kernel/FS/VirtualFileSystem.h>
@@ -202,7 +202,7 @@ argument_done:
 			SpinLock spinlock;
 			thread_data_t thread_data = { this, spinlock, arguments };
 			spinlock.lock();
-			TRY(Scheduler::get().add_thread(TRY(Thread::create(function, &thread_data))));
+			TRY(Process::current()->add_thread(function, &thread_data));
 			while (spinlock.is_locked());
 		}
 		else if (arguments.front() == "memory")

kernel/kernel/Thread.cpp

@@ -1,7 +1,7 @@
 #include <BAN/Errors.h>
-#include <kernel/Arch.h>
 #include <kernel/InterruptController.h>
 #include <kernel/kmalloc.h>
+#include <kernel/Process.h>
 #include <kernel/Scheduler.h>
 #include <kernel/Thread.h>
 
@@ -10,8 +10,6 @@
 namespace Kernel
 {
 
-	static uint32_t s_next_tid = 0;
-
 	static constexpr size_t thread_stack_size = 16384;
 
 	template<size_t size, typename T>
@@ -21,17 +19,28 @@ namespace Kernel
 		memcpy((void*)rsp, (void*)&value, size);
 	}
 
-	BAN::ErrorOr<BAN::RefPtr<Thread>> Thread::create(entry_t entry, void* data)
+	BAN::ErrorOr<BAN::RefPtr<Thread>> Thread::create(entry_t entry, void* data, BAN::RefPtr<Process> process)
 	{
-		auto thread = TRY(BAN::RefPtr<Thread>::create());
+		static pid_t next_tid = 1;
+		auto thread = TRY(BAN::RefPtr<Thread>::create(next_tid++, process));
 		TRY(thread->initialize(entry, data));
 		return thread;
 	}
 
-	Thread::Thread()
-		: m_tid(s_next_tid++)
+	Thread::Thread(pid_t tid, BAN::RefPtr<Process> process)
+		: m_tid(tid), m_process(process)
 	{}
 
+	BAN::RefPtr<Thread> Thread::current()
+	{
+		return Scheduler::get().current_thread();
+	}
+
+	BAN::RefPtr<Process> Thread::process()
+	{
+		return m_process;
+	}
+
 	BAN::ErrorOr<void> Thread::initialize(entry_t entry, void* data)
 	{
 		m_stack_base = kmalloc(thread_stack_size, PAGE_SIZE);
@@ -54,6 +63,8 @@ namespace Kernel
 
 	void Thread::on_exit()
 	{
+		if (m_process)
+			m_process->on_thread_exit(*this);
 		Scheduler::get().set_current_thread_done();
 		ASSERT_NOT_REACHED();
 	}

kernel/kernel/kernel.cpp

@@ -12,6 +12,7 @@
 #include <kernel/PCI.h>
 #include <kernel/PIC.h>
 #include <kernel/PIT.h>
+#include <kernel/Process.h>
 #include <kernel/Scheduler.h>
 #include <kernel/Serial.h>
 #include <kernel/Shell.h>
@@ -85,6 +86,8 @@ extern "C" uintptr_t g_userspace_end;
 
 extern void userspace_entry();
 
+void init2(void*);
+
 extern "C" void kernel_main()
 {
 	using namespace Kernel;
@@ -121,6 +124,7 @@ extern "C" void kernel_main()
 	ASSERT(terminal_driver);
 	dprintln("VESA initialized");
 	TTY* tty1 = new TTY(terminal_driver);
+	ASSERT(tty1);
 	
 	InterruptController::initialize(cmdline.force_pic);
 	dprintln("Interrupt controller initialized");
@@ -134,7 +138,7 @@ extern "C" void kernel_main()
 
 	MUST(Scheduler::initialize());
 	Scheduler& scheduler = Scheduler::get();
-#if 1
+#if 0 
 	MUST(scheduler.add_thread(MUST(Thread::create(
 		[] (void*)
 		{
@@ -178,27 +182,32 @@ extern "C" void kernel_main()
 		}
 	))));
 #else
-	MUST(scheduler.add_thread(MUST(Thread::create(
-		[](void* terminal_driver)
-		{
+	MUST(scheduler.add_thread(MUST(Thread::create(init2, tty1, nullptr))));
+#endif
+	scheduler.start();
+	ASSERT(false);
+}
+
+void init2(void* tty1_ptr)
+{
+	using namespace Kernel;
+
+	TTY* tty1 = (TTY*)tty1_ptr;
+
 	MUST(VirtualFileSystem::initialize());
 
 	auto font_or_error = Font::load("/usr/share/fonts/zap-ext-vga16.psf");
 	if (font_or_error.is_error())
 		dprintln("{}", font_or_error.error());
 	else
-				((TerminalDriver*)terminal_driver)->set_font(font_or_error.release_value());
-		}, terminal_driver
-	))));
-	MUST(scheduler.add_thread(MUST(Thread::create(
-		[](void* tty)
+		tty1->set_font(font_or_error.release_value());
+
+	MUST(Process::create_kernel(
+		[](void* tty1) 
 		{
-			Shell* shell = new Shell((TTY*)tty);
+			Shell* shell = new Shell((TTY*)tty1);
 			ASSERT(shell);
 			shell->run();
 		}, tty1
-	))));
-#endif
-	scheduler.start();
-	ASSERT(false);
+	));
 }

libc/include/sys/types.h

@@ -0,0 +1,10 @@
+#pragma once
+
+#include <stdint.h>
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+typedef int32_t pid_t;
+
+__END_DECLS