Handout

2025-10-31 22:37:36 +01:00
commit 174fe17e89
197 changed files with 79558 additions and 0 deletions
--- a/kernel/interrupt/handlers.cc
+++ b/kernel/interrupt/handlers.cc
@@ -0,0 +1,134 @@
+#include "./handlers.h"
+
+#include "../arch/core_cr.h"
+#include "../arch/idt.h"
+#include "../arch/lapic.h"
+#include "../arch/system.h"
+#include "../debug/kernelpanic.h"
+#include "../debug/output.h"
+#include "../device/ps2controller.h"
+#include "./epilogues.h"
+#include "./guard.h"
+
+static void printContext(const InterruptContext *context) {
+	DBG << "ip: " << hex << context->cs << ':' << context->ip
+		<< " sp: " << context->ss << ':' << context->sp << " flags" << bin
+		<< context->flags << endl;
+}
+
+[[gnu::interrupt]] static void handle_invalid_opcode(
+	InterruptContext *context) {
+	DBG << "Invalid opcode encountered" << endl;
+	printContext(context);
+	kernelpanic("Invalid opcode!");
+}
+
+[[gnu::interrupt]] static void handle_double_fault(InterruptContext *context,
+												   uint64_t error) {
+	DBG << "Double fault encountered. Error code: " << dec << error << endl;
+	printContext(context);
+	kernelpanic("Double fault!");
+}
+
+[[gnu::interrupt]] static void handle_invalid_tss(InterruptContext *context,
+												  uint64_t error) {
+	DBG << "Invalid tss encountered. Offending selector idx: " << dec << error
+		<< endl;
+	printContext(context);
+	kernelpanic("Invalid TSS!");
+}
+
+[[gnu::interrupt]] static void handle_general_protection_fault(
+	InterruptContext *context, uint64_t error) {
+	DBG << "General protection fault encountered. Error code: " << dec << error
+		<< endl;
+	printContext(context);
+	kernelpanic("General protection fault!");
+}
+
+[[gnu::interrupt]] static void handle_page_fault(InterruptContext *context,
+												 uint64_t error) {
+	DBG << "Page fault encountered at linear address " << hex
+		<< Core::CR<2>::read() << endl
+		<< PageFaultError(error) << endl;
+	printContext(context);
+	kernelpanic("Page fault!");
+}
+
+/*! \brief Assembly interrupt handler for the keyboard.
+ *
+ * On keyboard interrupt, the register state is saved to and restored from the
+ * stack. This function wraps the handle_keyboard C-function.
+ *
+ */
+extern "C" [[gnu::interrupt]] void handle_keyboard_asm(
+	InterruptContext *context);
+
+/*! \brief Higher-level Interrupt handler for the keyboard.
+ *
+ * On keyboard interrupt, the PS2-Controller may contain a valid Key that has to
+ * be fetched.
+ *
+ */
+extern "C" void handle_keyboard() {
+	// DBG_VERBOSE << "Keyboard interrupt" << endl;
+	Key key;
+	if (PS2Controller::fetch(key)) {
+		// Ctrl-Alt-Delete should perform a reboot. This should still be done in
+		// prologue, to ensure that rebooting still works reliably in case of
+		// broken epilogues.
+		if (key.ctrl() && key.alt() && key.scancode == Key::Scancode::KEY_DEL) {
+			System::reboot();
+		}
+
+		// Check if the last key was processed by the epilogue
+		if (!Epilogues::key.valid()) {
+			// Make sure we can receive new interrupts
+			LAPIC::endOfInterrupt();
+			// Enqueue new epilogue
+			Epilogues::key = key;
+			Guard::relay(Epilogues::keyboard);
+			return;
+		}
+	}
+	LAPIC::endOfInterrupt();
+}
+
+[[maybe_unused, gnu::interrupt]] static void handle_panic(
+	InterruptContext *context) {
+	(void)context;
+	kernelpanic("Panic interrupt triggered!");
+}
+
+[[maybe_unused, gnu::interrupt]] static void handle_timer(
+	InterruptContext *context) {
+	// DBG_VERBOSE << "Timer interrupt" << endl;
+	(void)context;
+	LAPIC::endOfInterrupt();
+	Guard::relay(Epilogues::timer);
+}
+
+void initInterruptHandlers() {
+	// Some handlers that are useful for debugging
+	IDT::set(Core::Interrupt::Vector::INVALID_OPCODE,
+			 IDT::InterruptDescriptor::Returning(handle_invalid_opcode));
+	IDT::set(Core::Interrupt::Vector::DOUBLE_FAULT,
+			 IDT::InterruptDescriptor::DivergingWithError(handle_double_fault));
+	IDT::set(Core::Interrupt::Vector::INVALID_TSS,
+			 IDT::InterruptDescriptor::ReturningWithError(handle_invalid_tss));
+	IDT::set(Core::Interrupt::Vector::GENERAL_PROTECTION_FAULT,
+			 IDT::InterruptDescriptor::ReturningWithError(
+				 handle_general_protection_fault));
+	IDT::set(Core::Interrupt::Vector::PAGE_FAULT,
+			 IDT::InterruptDescriptor::ReturningWithError(handle_page_fault));
+
+	// TODO: Add more handlers here
+	IDT::set(Core::Interrupt::Vector::KEYBOARD,
+			 IDT::InterruptDescriptor::Returning(handle_keyboard_asm));
+	IDT::set(Core::Interrupt::Vector::PANIC,
+			 IDT::InterruptDescriptor::Returning(handle_panic));
+	IDT::set(Core::Interrupt::Vector::TIMER,
+			 IDT::InterruptDescriptor::Returning(handle_timer));
+	// Load the idt pointer
+	IDT::load();
+}