interrupts

Cargo.lock

@@ -29,12 +29,22 @@ dependencies = [
  "spin",
 ]
 
+[[package]]
+name = "pic8259"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "08cc920d83ee33c0f9b73aa441e75468bf2d10c959a3eb6260cf720b05ac91a1"
+dependencies = [
+ "x86_64",
+]
+
 [[package]]
 name = "rust_os"
 version = "0.1.0"
 dependencies = [
  "bootloader",
  "lazy_static",
+ "pic8259",
  "spin",
  "uart_16550",
  "volatile 0.2.7",

Cargo.toml

@@ -9,6 +9,7 @@ volatile = "0.2.6"
 spin = "0.5.2"
 x86_64 = "0.14.2"
 uart_16550 = "0.2.0"
+pic8259 = "0.10.1"
 
 [dependencies.lazy_static]
 version = "1.0"

src/gdt.rs

@@ -36,12 +36,12 @@ struct Selectors {
 }
 
 pub fn init() {
-	use x86_64::instructions::segmentation::set_cs;
+	use x86_64::instructions::segmentation::{CS, Segment};
 	use x86_64::instructions::tables::load_tss;
     
 	GDT.0.load();
 	unsafe {
-	    set_cs(GDT.1.code_selector);
+	    CS::set_reg(GDT.1.code_selector);
 	    load_tss(GDT.1.tss_selector);
 	}
 }

src/interrupts.rs

@@ -1,5 +1,6 @@
 use x86_64::structures::idt::{InterruptDescriptorTable, InterruptStackFrame};
 use crate::println;
+use crate::print;
 
 use lazy_static::lazy_static;
 use crate::gdt;
@@ -10,9 +11,12 @@ lazy_static! {
         idt.breakpoint.set_handler_fn(breakpoint_handler);
         unsafe {
             idt.double_fault.set_handler_fn(double_fault_handler)
-                .set_stack_index(gdt::DOUBLE_FAULT_IST_INDEX); // new
+                .set_stack_index(gdt::DOUBLE_FAULT_IST_INDEX);
         }
-
+        idt[InterruptIndex::Timer.as_usize()]
+            .set_handler_fn(timer_interrupt_handler);
+        idt[InterruptIndex::Keyboard.as_usize()]
+            .set_handler_fn(keyboard_interrupt_handler);
         idt
     };
 }
@@ -23,6 +27,27 @@ extern "x86-interrupt" fn double_fault_handler(
 	panic!("EXCEPTION: DOUBLE FAULT\n{:#?}", stack_frame);
 }
 
+extern "x86-interrupt" fn timer_interrupt_handler(
+    _stack_frame: InterruptStackFrame)
+{
+    print!(".");
+    unsafe {
+        PICS.lock()
+            .notify_end_of_interrupt(InterruptIndex::Timer.as_u8());
+    }
+}
+
+extern "x86-interrupt" fn keyboard_interrupt_handler(
+    _stack_frame: InterruptStackFrame)
+{
+    print!("k");
+
+    unsafe {
+        PICS.lock()
+            .notify_end_of_interrupt(InterruptIndex::Keyboard.as_u8());
+    }
+}
+
 pub fn init_idt() {
     IDT.load();
 }
@@ -37,3 +62,29 @@ extern "x86-interrupt" fn breakpoint_handler(
 {
     println!("EXCEPTION: BREAKPOINT\n{:#?}", stack_frame);
 }
+
+use pic8259::ChainedPics;
+use spin;
+
+pub const PIC_1_OFFSET: u8 = 32;
+pub const PIC_2_OFFSET: u8 = PIC_1_OFFSET + 8;
+
+pub static PICS: spin::Mutex<ChainedPics> =
+    spin::Mutex::new(unsafe { ChainedPics::new(PIC_1_OFFSET, PIC_2_OFFSET) });
+
+#[derive(Debug, Clone, Copy)]
+#[repr(u8)]
+pub enum InterruptIndex {
+    Timer = PIC_1_OFFSET,
+    Keyboard,
+}
+
+impl InterruptIndex {
+    fn as_u8(self) -> u8 {
+        self as u8
+    }
+
+    fn as_usize(self) -> usize {
+        usize::from(self.as_u8())
+    }
+}

src/lib.rs

@@ -39,12 +39,14 @@ pub fn test_panic_handler(info: &PanicInfo) -> ! {
     serial_println!("[failed]\n");
     serial_println!("Error: {}\n", info);
     exit_qemu(QemuExitCode::Failed);
-    loop {}
+    hlt_loop();
 }
 
 pub fn init() {
 	gdt::init();
 	interrupts::init_idt();
+    unsafe { interrupts::PICS.lock().initialize() };
+    x86_64::instructions::interrupts::enable();
 }
 
 #[cfg(test)]
@@ -52,7 +54,7 @@ pub fn init() {
 pub extern "C" fn _start() -> ! {
     init();      // new
     test_main();
-    loop {}
+    hlt_loop();
 }
 
 #[cfg(test)]
@@ -76,3 +78,9 @@ pub fn exit_qemu(exit_code: QemuExitCode) {
         port.write(exit_code as u32);
     }
 }
+
+pub fn hlt_loop() -> ! {
+    loop {
+        x86_64::instructions::hlt();
+    }
+}

src/main.rs

@@ -18,7 +18,7 @@ pub extern "C" fn _start() -> ! {
     test_main();
 
     println!("It did not crash!");
-    loop {}
+    rust_os::hlt_loop();
 }
 
 /// This function is called on panic.
@@ -26,7 +26,7 @@ pub extern "C" fn _start() -> ! {
 #[panic_handler]
 fn panic(info: &PanicInfo) -> ! {
     println!("{}", info);
-    loop {}
+    rust_os::hlt_loop();
 }
 
 #[cfg(test)]

src/serial.rs

@@ -13,7 +13,14 @@ lazy_static! {
 #[doc(hidden)]
 pub fn _print(args: ::core::fmt::Arguments) {
     use core::fmt::Write;
-    SERIAL1.lock().write_fmt(args).expect("Printing to serial failed");
+    use x86_64::instructions::interrupts;
+
+    interrupts::without_interrupts(|| {
+        SERIAL1
+            .lock()
+            .write_fmt(args)
+            .expect("Printing to serial failed");
+    });
 }
 
 /// Prints to the host through the serial interface.

src/vga_buffer.rs

@@ -142,7 +142,11 @@ macro_rules! println {
 #[doc(hidden)]
 pub fn _print(args: fmt::Arguments) {
     use core::fmt::Write;
+    use x86_64::instructions::interrupts;
+
+    interrupts::without_interrupts(|| {
         WRITER.lock().write_fmt(args).unwrap();
+    });
 }
 
 #[test_case]
@@ -159,10 +163,16 @@ fn test_println_many() {
 
 #[test_case]
 fn test_println_output() {
+    use core::fmt::Write;
+    use x86_64::instructions::interrupts;
+
     let s = "Some test string that fits on a single line";
-    println!("{}", s);
+    interrupts::without_interrupts(|| {
+        let mut writer = WRITER.lock();
+        writeln!(writer, "\n{}", s).expect("writeln failed");
         for (i, c) in s.chars().enumerate() {
-        let screen_char = WRITER.lock().buffer.chars[BUFFER_HEIGHT - 2][i].read();
+            let screen_char = writer.buffer.chars[BUFFER_HEIGHT - 2][i].read();
             assert_eq!(char::from(screen_char.ascii_character), c);
         }
+    });
 }