Important: License changed from MIT to GPL.

Rewrote the README based on the actual project.

19 files changed, 72 insertions, 0 deletions

diff --git a/src/kernel/bio.cc b/src/kernel/bio.cc
index 6e63d60..5f1aae9 100644
--- a/src/kernel/bio.cc
+++ b/src/kernel/bio.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "kernel/buf.h"
 #include "kernel/spinlock.h"
 #include "kernel/riscv.h"
diff --git a/src/kernel/config.cc b/src/kernel/config.cc
index 47f7a3e..36858a1 100644
--- a/src/kernel/config.cc
+++ b/src/kernel/config.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "common/types.h"
 
 uint64 g_uart_base = 0;
diff --git a/src/kernel/cxx.cc b/src/kernel/cxx.cc
index 14bfe68..00f2799 100644
--- a/src/kernel/cxx.cc
+++ b/src/kernel/cxx.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "common/types.h"
 #include "kernel/pmm.h"
 #include "drivers/uart.h"
diff --git a/src/kernel/fdt.cc b/src/kernel/fdt.cc
index 5334845..e9f8422 100644
--- a/src/kernel/fdt.cc
+++ b/src/kernel/fdt.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "common/types.h"
 #include "drivers/uart.h"
 #include "kernel/config.h"
diff --git a/src/kernel/initcode.S b/src/kernel/initcode.S
index 8b56ce6..22e55ca 100644
--- a/src/kernel/initcode.S
+++ b/src/kernel/initcode.S
@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (C) 2026 Richard Qin
+
 .section .rodata
 .global initcode_start
 .global initcode_end
diff --git a/src/kernel/main.cc b/src/kernel/main.cc
index 9a24028..22cffd6 100644
--- a/src/kernel/main.cc
+++ b/src/kernel/main.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "common/types.h"
 #include "kernel/riscv.h"
 #include "drivers/uart.h"
diff --git a/src/kernel/mm/pmm.cc b/src/kernel/mm/pmm.cc
index e871d8a..2d0c44f 100644
--- a/src/kernel/mm/pmm.cc
+++ b/src/kernel/mm/pmm.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "common/types.h"
 #include "kernel/riscv.h"
 #include "kernel/pmm.h"
diff --git a/src/kernel/mm/slab.cc b/src/kernel/mm/slab.cc
index 702dc5c..3bb6b1b 100644
--- a/src/kernel/mm/slab.cc
+++ b/src/kernel/mm/slab.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "kernel/slab.h"
 #include "kernel/pmm.h"
 #include "kernel/spinlock.h"
diff --git a/src/kernel/mm/vm.cc b/src/kernel/mm/vm.cc
index 1155d2c..47b80e9 100644
--- a/src/kernel/mm/vm.cc
+++ b/src/kernel/mm/vm.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "kernel/mm.h"
 #include "kernel/pmm.h"
 #include "kernel/riscv.h"
diff --git a/src/kernel/proc/exec.cc b/src/kernel/proc/exec.cc
index 22e4842..e5294d9 100644
--- a/src/kernel/proc/exec.cc
+++ b/src/kernel/proc/exec.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "common/types.h"
 #include "kernel/riscv.h"
 #include "kernel/proc.h"
diff --git a/src/kernel/proc/proc.cc b/src/kernel/proc/proc.cc
index 6940a3e..3923fe8 100644
--- a/src/kernel/proc/proc.cc
+++ b/src/kernel/proc/proc.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "kernel/proc.h"
 #include "kernel/proc_def.h"
 #include "kernel/runqueue.h"
diff --git a/src/kernel/proc/swtch.S b/src/kernel/proc/swtch.S
index f59de20..d55c03e 100644
--- a/src/kernel/proc/swtch.S
+++ b/src/kernel/proc/swtch.S
@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (C) 2026 Richard Qin
+
 .global swtch
 
 swtch:
diff --git a/src/kernel/sbi.cc b/src/kernel/sbi.cc
index 9570d74..5ae7edb 100644
--- a/src/kernel/sbi.cc
+++ b/src/kernel/sbi.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "common/types.h"
 #include "kernel/sbi.h"
 
diff --git a/src/kernel/spinlock.cc b/src/kernel/spinlock.cc
index 55dfc6b..aadce21 100644
--- a/src/kernel/spinlock.cc
+++ b/src/kernel/spinlock.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "kernel/spinlock.h"
 #include "kernel/riscv.h"
 #include "kernel/cpu.h"
diff --git a/src/kernel/syscall.cc b/src/kernel/syscall.cc
index 9f88649..b891ada 100644
--- a/src/kernel/syscall.cc
+++ b/src/kernel/syscall.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "kernel/syscall.h"
 #include "common/types.h"
 #include "common/fcntl.h"
diff --git a/src/kernel/timer.cc b/src/kernel/timer.cc
index 3cbf11e..fc02f27 100644
--- a/src/kernel/timer.cc
+++ b/src/kernel/timer.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "common/types.h"
 #include "kernel/config.h"
 #include "kernel/spinlock.h"
diff --git a/src/kernel/trap/handler.cc b/src/kernel/trap/handler.cc
index 7e4d11e..11af409 100644
--- a/src/kernel/trap/handler.cc
+++ b/src/kernel/trap/handler.cc
@@ -1,3 +1,7 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2026 Richard QIn
+ */
 #include "kernel/trap.h"
 #include "kernel/riscv.h"
 #include "kernel/proc.h"
diff --git a/src/kernel/trap/trampoline.S b/src/kernel/trap/trampoline.S
index 478d345..57d6f25 100644
--- a/src/kernel/trap/trampoline.S
+++ b/src/kernel/trap/trampoline.S
@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (C) 2026 Richard Qin
+
 .section .text
 .globl trampoline
 .globl uservec
diff --git a/src/kernel/trap/trap.S b/src/kernel/trap/trap.S
index 573248e..8bce53d 100644
--- a/src/kernel/trap/trap.S
+++ b/src/kernel/trap/trap.S
@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (C) 2026 Richard Qin
+
 .section .text
 .global kernelvec
 .global uservec