From 216089c7a1d1b20d14a3c278aa32c43b93f21971 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=B6nke=20Holz?= <sholz8530@gmail.com>
Date: Sat, 13 Apr 2024 10:26:50 +0200
Subject: [PATCH] Kernel: Add a Thread member for arch-specific data

This will be used to store the fs_base value on x86-64, which is needed
for thread-local storage.
---
 Kernel/Arch/ArchSpecificThreadData.h         | 19 +++++++++++++++++++
 Kernel/Arch/aarch64/ArchSpecificThreadData.h | 16 ++++++++++++++++
 Kernel/Arch/riscv64/ArchSpecificThreadData.h | 16 ++++++++++++++++
 Kernel/Arch/x86_64/ArchSpecificThreadData.h  | 16 ++++++++++++++++
 Kernel/Tasks/Thread.cpp                      |  1 +
 Kernel/Tasks/Thread.h                        |  4 ++++
 6 files changed, 72 insertions(+)
 create mode 100644 Kernel/Arch/ArchSpecificThreadData.h
 create mode 100644 Kernel/Arch/aarch64/ArchSpecificThreadData.h
 create mode 100644 Kernel/Arch/riscv64/ArchSpecificThreadData.h
 create mode 100644 Kernel/Arch/x86_64/ArchSpecificThreadData.h

diff --git a/Kernel/Arch/ArchSpecificThreadData.h b/Kernel/Arch/ArchSpecificThreadData.h
new file mode 100644
index 0000000000..3a03a17b00
--- /dev/null
+++ b/Kernel/Arch/ArchSpecificThreadData.h
@@ -0,0 +1,19 @@
+/*
+ * Copyright (c) 2024, Sönke Holz <sholz8530@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Platform.h>
+
+#if ARCH(X86_64)
+#    include <Kernel/Arch/x86_64/ArchSpecificThreadData.h>
+#elif ARCH(AARCH64)
+#    include <Kernel/Arch/aarch64/ArchSpecificThreadData.h>
+#elif ARCH(RISCV64)
+#    include <Kernel/Arch/riscv64/ArchSpecificThreadData.h>
+#else
+#    error Unknown architecture
+#endif
diff --git a/Kernel/Arch/aarch64/ArchSpecificThreadData.h b/Kernel/Arch/aarch64/ArchSpecificThreadData.h
new file mode 100644
index 0000000000..5dbe07b8d2
--- /dev/null
+++ b/Kernel/Arch/aarch64/ArchSpecificThreadData.h
@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024, Sönke Holz <sholz8530@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Types.h>
+
+namespace Kernel {
+
+struct ArchSpecificThreadData {
+};
+
+}
diff --git a/Kernel/Arch/riscv64/ArchSpecificThreadData.h b/Kernel/Arch/riscv64/ArchSpecificThreadData.h
new file mode 100644
index 0000000000..5dbe07b8d2
--- /dev/null
+++ b/Kernel/Arch/riscv64/ArchSpecificThreadData.h
@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024, Sönke Holz <sholz8530@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Types.h>
+
+namespace Kernel {
+
+struct ArchSpecificThreadData {
+};
+
+}
diff --git a/Kernel/Arch/x86_64/ArchSpecificThreadData.h b/Kernel/Arch/x86_64/ArchSpecificThreadData.h
new file mode 100644
index 0000000000..5dbe07b8d2
--- /dev/null
+++ b/Kernel/Arch/x86_64/ArchSpecificThreadData.h
@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024, Sönke Holz <sholz8530@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Types.h>
+
+namespace Kernel {
+
+struct ArchSpecificThreadData {
+};
+
+}
diff --git a/Kernel/Tasks/Thread.cpp b/Kernel/Tasks/Thread.cpp
index 8596c3a6c7..67aeec0f05 100644
--- a/Kernel/Tasks/Thread.cpp
+++ b/Kernel/Tasks/Thread.cpp
@@ -1210,6 +1210,7 @@ ErrorOr<NonnullRefPtr<Thread>> Thread::clone(NonnullRefPtr<Process> process)
     clone->m_signal_mask = m_signal_mask;
     clone->m_fpu_state = m_fpu_state;
     clone->m_thread_specific_data = m_thread_specific_data;
+    clone->m_arch_specific_data = m_arch_specific_data;
     return clone;
 }
 
diff --git a/Kernel/Tasks/Thread.h b/Kernel/Tasks/Thread.h
index c73cc8e331..85129a9edd 100644
--- a/Kernel/Tasks/Thread.h
+++ b/Kernel/Tasks/Thread.h
@@ -20,6 +20,7 @@
 #include <Kernel/API/POSIX/sched.h>
 #include <Kernel/API/POSIX/select.h>
 #include <Kernel/API/POSIX/signal_numbers.h>
+#include <Kernel/Arch/ArchSpecificThreadData.h>
 #include <Kernel/Arch/RegisterState.h>
 #include <Kernel/Arch/ThreadRegisters.h>
 #include <Kernel/Debug.h>
@@ -790,6 +791,8 @@ public:
     StringView state_string() const;
 
     VirtualAddress thread_specific_data() const { return m_thread_specific_data; }
+    ArchSpecificThreadData& arch_specific_data() { return m_arch_specific_data; }
+    ArchSpecificThreadData const& arch_specific_data() const { return m_arch_specific_data; }
 
     ALWAYS_INLINE void yield_if_should_be_stopped()
     {
@@ -1193,6 +1196,7 @@ private:
     IntrusiveListNode<Thread> m_blocked_threads_list_node;
     LockRank m_lock_rank_mask {};
     bool m_allocation_enabled { true };
+    ArchSpecificThreadData m_arch_specific_data;
 
     // FIXME: remove this after annihilating Process::m_big_lock
     IntrusiveListNode<Thread> m_big_lock_blocked_threads_list_node;