drivers: implement EventListener

drivers/Cargo.toml

@@ -8,7 +8,7 @@ description = "Device drivers of zCore"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [features]
-mock = []
+mock = ["async-std"]
 virtio = ["virtio-drivers"]
 
 [dependencies]
@@ -16,4 +16,6 @@ log = "0.4"
 spin = "0.9"
 cfg-if = "1.0"
 bitflags = "1.3"
+lazy_static = "1.4"
 virtio-drivers = { git = "https://github.com/rcore-os/virtio-drivers", rev = "2b3c6cf", optional = true }
+async-std = { version = "1.10", optional = true }

drivers/src/lib.rs

@@ -29,4 +29,4 @@ pub enum DeviceError {
 
 pub type DeviceResult<T = ()> = core::result::Result<T, DeviceError>;
 
-pub type IrqHandler = alloc::boxed::Box<dyn Fn() + Send + Sync>;
+pub type IrqHandler = alloc::boxed::Box<dyn Fn(u32) + Send + Sync>;

drivers/src/mock/uart.rs

@@ -1,28 +1,43 @@
-use std::io::{self, Read};
-use std::sync::mpsc::{self, Receiver};
+use std::collections::VecDeque;
 use std::sync::Mutex;
 
+use async_std::{io, io::prelude::*, task};
+
 use crate::scheme::{Scheme, UartScheme};
 use crate::DeviceResult;
 
-pub struct MockUart {
-    stdin_channel: Mutex<Receiver<u8>>,
+const UART_BUF_LEN: usize = 256;
+
+lazy_static::lazy_static! {
+    static ref UART_BUF: Mutex<VecDeque<u8>> = Mutex::new(VecDeque::with_capacity(UART_BUF_LEN));
 }
 
+pub struct MockUart;
+
 impl MockUart {
     pub fn new() -> Self {
-        let (tx, rx) = mpsc::channel();
-        std::thread::spawn(move || loop {
-            let mut buf = [0];
-            io::stdin().read_exact(&mut buf).unwrap();
-            if tx.send(buf[0]).is_err() {
-                break;
+        Self
+    }
+
+    pub fn start_irq_serve(irq_handler: impl Fn() + Send + Sync + 'static) {
+        task::spawn(async move {
+            loop {
+                let mut buf = [0; UART_BUF_LEN];
+                let remains = UART_BUF_LEN - UART_BUF.lock().unwrap().len();
+                if remains > 0 {
+                    if let Ok(n) = io::stdin().read(&mut buf[..remains]).await {
+                        {
+                            let mut uart_buf = UART_BUF.lock().unwrap();
+                            for c in &buf[..n] {
+                                uart_buf.push_back(*c);
+                            }
+                        }
+                        irq_handler();
+                    }
+                }
+                task::yield_now().await;
             }
-            core::hint::spin_loop();
         });
-        Self {
-            stdin_channel: Mutex::new(rx),
-        }
     }
 }
 
@@ -36,9 +51,10 @@ impl Scheme for MockUart {}
 
 impl UartScheme for MockUart {
     fn try_recv(&self) -> DeviceResult<Option<u8>> {
-        match self.stdin_channel.lock().unwrap().try_recv() {
-            Ok(ch) => Ok(Some(ch)),
-            _ => Ok(None),
+        if let Some(c) = UART_BUF.lock().unwrap().pop_front() {
+            Ok(Some(c))
+        } else {
+            Ok(None)
         }
     }
 
@@ -56,10 +72,14 @@ impl UartScheme for MockUart {
 #[cfg(test)]
 mod test {
     use super::*;
+    use std::sync::Arc;
 
     #[test]
     fn test_mock_uart() {
-        let uart = MockUart::new();
+        let uart = Arc::new(MockUart::new());
+        let u = uart.clone();
+        MockUart::start_irq_serve(move || u.handle_irq(0));
+
         uart.write_str("Hello, World!\n").unwrap();
         uart.write_str(format!("{} + {} = {}\n", 1, 2, 1 + 2).as_str())
             .unwrap();

drivers/src/scheme/event.rs

@@ -0,0 +1,46 @@
+use alloc::vec::Vec;
+
+use spin::Mutex;
+
+use super::{Scheme, UartScheme};
+use crate::{DeviceResult, IrqHandler};
+
+pub struct EventListener<T: Scheme> {
+    inner: T,
+    events: Mutex<Vec<(IrqHandler, bool)>>,
+}
+
+impl<T: Scheme> EventListener<T> {
+    pub fn new(inner: T) -> Self {
+        Self {
+            inner,
+            events: Mutex::new(Vec::new()),
+        }
+    }
+}
+
+impl<T: Scheme> Scheme for EventListener<T> {
+    fn handle_irq(&self, irq_num: u32) {
+        self.inner.handle_irq(irq_num);
+        self.events.lock().retain(|(f, once)| {
+            f(irq_num);
+            !once
+        });
+    }
+
+    fn subscribe(&self, handler: IrqHandler, once: bool) {
+        self.events.lock().push((handler, once));
+    }
+}
+
+impl<T: UartScheme> UartScheme for EventListener<T> {
+    fn try_recv(&self) -> DeviceResult<Option<u8>> {
+        self.inner.try_recv()
+    }
+    fn send(&self, ch: u8) -> DeviceResult {
+        self.inner.send(ch)
+    }
+    fn write_str(&self, s: &str) -> DeviceResult {
+        self.inner.write_str(s)
+    }
+}

drivers/src/scheme/mod.rs

@@ -1,15 +1,20 @@
 mod block;
 mod display;
+mod event;
 mod input;
 mod net;
 mod uart;
 
 pub use block::BlockScheme;
 pub use display::DisplayScheme;
+pub use event::EventListener;
 pub use input::InputScheme;
 pub use net::NetScheme;
 pub use uart::UartScheme;
 
 pub trait Scheme: Send + Sync {
     fn handle_irq(&self, _irq_num: u32) {}
+    fn subscribe(&self, _handler: crate::IrqHandler, _once: bool) {
+        unimplemented!("please call `subscribe()` with the `EventListener` wrapper")
+    }
 }

drivers/src/uart/uart_16550.rs

@@ -102,11 +102,6 @@ where
     fn write_str(&mut self, s: &str) -> DeviceResult {
         for b in s.bytes() {
             match b {
-                8 | 0x7F => {
-                    self.send(8)?;
-                    self.send(b' ')?;
-                    self.send(8)?;
-                }
                 b'\n' => {
                     self.send(b'\r')?;
                     self.send(b'\n')?;

drivers/src/virtio/blk.rs

@@ -16,7 +16,11 @@ impl<'a> VirtIoBlk<'a> {
     }
 }
 
-impl<'a> Scheme for VirtIoBlk<'a> {}
+impl<'a> Scheme for VirtIoBlk<'a> {
+    fn handle_irq(&self, _irq_num: u32) {
+        self.inner.lock().ack_interrupt();
+    }
+}
 
 impl<'a> BlockScheme for VirtIoBlk<'a> {
     fn read_block(&self, block_id: usize, buf: &mut [u8]) -> DeviceResult {

drivers/src/virtio/console.rs

@@ -18,7 +18,11 @@ impl<'a> VirtIoConsole<'a> {
     }
 }
 
-impl<'a> Scheme for VirtIoConsole<'a> {}
+impl<'a> Scheme for VirtIoConsole<'a> {
+    fn handle_irq(&self, _irq_num: u32) {
+        self.inner.lock().ack_interrupt().unwrap();
+    }
+}
 
 impl<'a> UartScheme for VirtIoConsole<'a> {
     fn try_recv(&self) -> DeviceResult<Option<u8>> {

kernel-hal/Cargo.toml

@@ -28,7 +28,7 @@ zcore-drivers = { path = "../drivers" }
 libc = "0.2"
 tempfile = "3"
 lazy_static = "1.4"
-async-std = { version = "1.9", optional = true }
+async-std = { version = "1.10", optional = true }
 
 # Bare-metal mode
 [target.'cfg(target_os = "none")'.dependencies]

kernel-hal/src/bare/arch/riscv/drivers.rs

@@ -1,11 +1,12 @@
 use alloc::boxed::Box;
 
+use zcore_drivers::scheme::EventListener;
 use zcore_drivers::uart::Uart16550Mmio;
 
 use crate::{drivers::UART, mem::phys_to_virt};
 
 pub(super) fn init() {
-    UART.init_by(Box::new(unsafe {
+    UART.init_by(Box::new(EventListener::new(unsafe {
         Uart16550Mmio::<u8>::new(phys_to_virt(super::consts::UART_BASE))
-    }));
+    })));
 }

kernel-hal/src/bare/arch/riscv/interrupt.rs

@@ -11,7 +11,7 @@ const U_PLIC: u32 = 8;
 const S_PLIC: u32 = 9;
 const M_PLIC: u32 = 11;
 
-lazy_static::lazy_static! {
+lazy_static! {
     static ref IRQ_MANAGER: Mutex<IrqManager> = Mutex::new(IrqManager::new(1, 15));
 }
 

kernel-hal/src/bare/arch/riscv/mod.rs

@@ -17,9 +17,9 @@ pub mod vm;
 
 pub fn init() {
     vm::remap_the_kernel().unwrap();
+    drivers::init();
     interrupt::init();
     timer::init();
-    drivers::init();
 
     #[cfg(feature = "board_qemu")]
     {

kernel-hal/src/bare/arch/riscv/plic.rs

@@ -88,7 +88,7 @@ pub(super) fn handle_interrupt() {
             }
             UART0_INT_NUM => {
                 //UART中断ID是10
-                crate::serial::handle_irq();
+                crate::drivers::UART.handle_irq(UART0_INT_NUM);
 
                 //换用sbi的方式获取字符
                 //interrupt::try_process_serial();

kernel-hal/src/bare/arch/x86_64/acpi_table.rs

@@ -13,7 +13,7 @@ pub struct AcpiTable {
     inner: Acpi,
 }
 
-lazy_static::lazy_static! {
+lazy_static! {
     static ref ACPI_TABLE: Mutex<Option<AcpiTable>> = Mutex::default();
 }
 

kernel-hal/src/bare/arch/x86_64/cpu.rs

@@ -1,4 +1,4 @@
-lazy_static::lazy_static! {
+lazy_static! {
     static ref TSC_FREQUENCY: u16 = {
         const DEFAULT: u16 = 2600;
         if let Some(info) = raw_cpuid::CpuId::new().get_processor_frequency_info() {

kernel-hal/src/bare/arch/x86_64/drivers.rs

@@ -1,9 +1,10 @@
 use alloc::boxed::Box;
 
+use zcore_drivers::scheme::EventListener;
 use zcore_drivers::uart::Uart16550Pio;
 
 use crate::drivers::UART;
 
 pub(super) fn init() {
-    UART.init_by(Box::new(Uart16550Pio::new(0x3F8)));
+    UART.init_by(Box::new(EventListener::new(Uart16550Pio::new(0x3F8))));
 }

kernel-hal/src/bare/arch/x86_64/interrupt.rs

@@ -28,7 +28,7 @@ const Spurious: u32 = 31;
 
 const IO_APIC_NUM_REDIRECTIONS: u8 = 120;
 
-lazy_static::lazy_static! {
+lazy_static! {
     static ref IRQ_MANAGER: Mutex<IrqManager> = Mutex::new(IrqManager::new(0x20, 0xff));
     static ref MAX_INSTR_TABLE: Mutex<Vec<(usize, u8)>> = Mutex::default();
 }
@@ -239,10 +239,6 @@ fn timer() {
     crate::timer::timer_tick();
 }
 
-fn com1() {
-    crate::serial::handle_irq();
-}
-
 /*
 fn keyboard() {
     use pc_keyboard::{DecodedKey, KeyCode};
@@ -285,7 +281,11 @@ pub(super) fn init() {
         .ok();
     // im.register_handler(Keyboard + IRQ_MIN_ID, Box::new(keyboard));
     // im.register_handler(Mouse + IRQ_MIN_ID, Box::new(mouse));
-    im.register_handler(COM1 + IRQ_MIN_ID, Box::new(com1)).ok();
+    im.register_handler(
+        COM1 + IRQ_MIN_ID,
+        Box::new(|| crate::drivers::UART.handle_irq(COM1)),
+    )
+    .ok();
     im.register_handler(57u32, Box::new(irq57test)).ok();
     // register_handler(Keyboard, Keyboard + IRQ_MIN_ID);
     // register_handler(Mouse, Mouse + IRQ_MIN_ID);

kernel-hal/src/bare/timer.rs

@@ -4,7 +4,7 @@ use core::time::Duration;
 use naive_timer::Timer;
 use spin::Mutex;
 
-lazy_static::lazy_static! {
+lazy_static! {
     pub static ref NAIVE_TIMER: Mutex<Timer> = Mutex::new(Timer::default());
 }
 

kernel-hal/src/common/future.rs

@@ -1,17 +1,11 @@
 use alloc::boxed::Box;
-use core::future::Future;
-use core::pin::Pin;
 use core::task::{Context, Poll};
 use core::time::Duration;
-
-/// Yields execution back to the async runtime.
-pub fn yield_now() -> impl Future<Output = ()> {
-    YieldFuture::default()
-}
+use core::{future::Future, pin::Pin};
 
 #[must_use = "yield_now does nothing unless polled/`await`-ed"]
 #[derive(Default)]
-struct YieldFuture {
+pub(super) struct YieldFuture {
     flag: bool,
 }
 
@@ -29,14 +23,15 @@ impl Future for YieldFuture {
     }
 }
 
-/// Sleeps until the specified of time.
-pub fn sleep_until(deadline: Duration) -> impl Future {
-    SleepFuture { deadline }
+#[must_use = "sleep does nothing unless polled/`await`-ed"]
+pub(super) struct SleepFuture {
+    deadline: Duration,
 }
 
-#[must_use = "sleep does nothing unless polled/`await`-ed"]
-pub struct SleepFuture {
-    deadline: Duration,
+impl SleepFuture {
+    pub fn new(deadline: Duration) -> Self {
+        Self { deadline }
+    }
 }
 
 impl Future for SleepFuture {
@@ -54,29 +49,37 @@ impl Future for SleepFuture {
     }
 }
 
-/// Get a char from serial.
-pub fn serial_getchar() -> impl Future<Output = u8> {
-    SerialFuture
+#[must_use = "serial_getchar does nothing unless polled/`await`-ed"]
+pub(super) struct SerialFuture<'a> {
+    buf: &'a mut [u8],
 }
 
-#[must_use = "serial_getchar does nothing unless polled/`await`-ed"]
-pub struct SerialFuture;
+impl<'a> SerialFuture<'a> {
+    pub fn new(buf: &'a mut [u8]) -> Self {
+        Self { buf }
+    }
+}
 
-impl Future for SerialFuture {
-    type Output = u8;
+impl Future for SerialFuture<'_> {
+    type Output = usize;
 
     fn poll(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> {
-        let mut buf = [0u8];
-        if crate::serial::serial_read(&mut buf) != 0 {
-            return Poll::Ready(buf[0]);
+        use crate::drivers::UART;
+        let buf = &mut self.get_mut().buf;
+        let mut n = 0;
+        for i in 0..buf.len() {
+            if let Some(c) = UART.try_recv().unwrap() {
+                buf[i] = if c == b'\r' { b'\n' } else { c };
+                n += 1;
+            } else {
+                break;
+            }
+        }
+        if n > 0 {
+            return Poll::Ready(n);
         }
         let waker = cx.waker().clone();
-        crate::serial::serial_set_callback(Box::new({
-            move || {
-                waker.wake_by_ref();
-                true
-            }
-        }));
+        UART.subscribe(Box::new(move |_| waker.wake_by_ref()), true);
         Poll::Pending
     }
 }

kernel-hal/src/common/mem.rs

@@ -72,7 +72,7 @@ impl Drop for PhysFrame {
     }
 }
 
-lazy_static::lazy_static! {
+lazy_static! {
     /// The global physical frame contains all zeros.
     pub static ref ZERO_FRAME: PhysFrame = PhysFrame::new_zero().expect("failed to alloc zero frame");
 }

kernel-hal/src/common/mod.rs

@@ -1,12 +1,14 @@
+mod future;
+
 pub(super) mod defs;
 pub(super) mod fb;
 
 pub mod addr;
 pub mod context;
 pub mod drivers;
-pub mod future;
 pub mod mem;
 pub mod serial;
+pub mod thread;
 pub mod user;
 pub mod vdso;
 pub mod vm;

kernel-hal/src/common/serial.rs

@@ -1,16 +1,7 @@
-use alloc::{boxed::Box, collections::VecDeque, vec::Vec};
 use core::fmt::{Arguments, Result, Write};
 
-use spin::Mutex;
-
 use crate::drivers::UART;
 
-lazy_static::lazy_static! {
-    static ref STDIN: Mutex<VecDeque<u8>> = Mutex::new(VecDeque::new());
-    static ref STDIN_CALLBACK: Mutex<Vec<Box<dyn Fn() -> bool + Send + Sync>>> =
-        Mutex::new(Vec::new());
-}
-
 struct SerialWriter;
 
 impl Write for SerialWriter {
@@ -22,31 +13,6 @@ impl Write for SerialWriter {
     }
 }
 
-pub(crate) fn handle_irq() {
-    if let Some(uart) = UART.try_get() {
-        if let Some(c) = uart.try_recv().unwrap() {
-            let c = if c == b'\r' { b'\n' } else { c };
-            STDIN.lock().push_back(c);
-            STDIN_CALLBACK.lock().retain(|f| !f());
-        }
-    }
-}
-
-/// Register a callback of serial readable event.
-pub fn serial_set_callback(callback: Box<dyn Fn() -> bool + Send + Sync>) {
-    STDIN_CALLBACK.lock().push(callback);
-}
-
-/// Read a string from serial buffer.
-pub fn serial_read(buf: &mut [u8]) -> usize {
-    let mut stdin = STDIN.lock();
-    let len = stdin.len().min(buf.len());
-    for c in &mut buf[..len] {
-        *c = stdin.pop_front().unwrap();
-    }
-    len
-}
-
 /// Print format string and its arguments to serial.
 pub fn serial_write_fmt(fmt: Arguments) {
     SerialWriter.write_fmt(fmt).unwrap();
@@ -56,3 +22,8 @@ pub fn serial_write_fmt(fmt: Arguments) {
 pub fn serial_write(s: &str) {
     serial_write_fmt(format_args!("{}", s));
 }
+
+/// Get a char from serial.
+pub async fn serial_read(buf: &mut [u8]) -> usize {
+    super::future::SerialFuture::new(buf).await
+}

kernel-hal/src/common/thread.rs

@@ -0,0 +1,13 @@
+use core::time::Duration;
+
+use super::future::{SleepFuture, YieldFuture};
+
+/// Sleeps until the specified of time.
+pub async fn sleep_until(deadline: Duration) {
+    SleepFuture::new(deadline).await
+}
+
+/// Yields execution back to the async runtime.
+pub async fn yield_now() {
+    YieldFuture::default().await
+}

kernel-hal/src/hal_fn.rs

@@ -33,12 +33,12 @@ hal_fn_def! {
     }
 
     pub mod vm: common::vm {
+        /// Read current VM token. (e.g. CR3, SATP, ...)
+        pub fn current_vmtoken() -> PhysAddr;
+
         /// Activate this page table by given `vmtoken`.
         pub(crate) fn activate_paging(vmtoken: PhysAddr);
 
-        /// Read current VM token. (e.g. CR3, SATP, ...)
-        pub(crate) fn current_vmtoken() -> PhysAddr;
-
         /// Flush TLB by the associated `vaddr`, or flush the entire TLB. (`vaddr` is `None`).
         pub(crate) fn flush_tlb(vaddr: Option<VirtAddr>);
 
@@ -103,7 +103,7 @@ hal_fn_def! {
         pub fn fetch_page_fault_info(info_reg: usize) -> (VirtAddr, MMUFlags);
     }
 
-    pub mod thread {
+    pub mod thread: common::thread {
         /// Spawn a new thread.
         pub fn spawn(future: Pin<Box<dyn Future<Output = ()> + Send + 'static>>, vmtoken: usize);
 

kernel-hal/src/lib.rs

@@ -5,12 +5,12 @@
 #![deny(warnings)]
 
 extern crate alloc;
-
 #[macro_use]
 extern crate log;
-
 #[macro_use]
 extern crate cfg_if;
+#[macro_use]
+extern crate lazy_static;
 
 #[macro_use]
 mod macros;
@@ -31,7 +31,7 @@ cfg_if! {
     }
 }
 
-pub use common::{addr, defs::*, drivers, future, serial, user};
+pub use common::{addr, defs::*, drivers, serial, user};
 pub use config::*;
 pub use imp::*;
 pub use kernel_handler::*;

kernel-hal/src/libos/dev/input.rs

@@ -20,7 +20,7 @@ struct InputEvent {
     value: i32,
 }
 
-lazy_static::lazy_static! {
+lazy_static! {
     static ref MOUSE_CALLBACK: Mutex<Vec<Box<MouseCallbackFn>>> = Mutex::new(Vec::new());
     static ref KBD_CALLBACK: Mutex<Vec<Box<KBDCallbackFn>>> = Mutex::new(Vec::new());
 }

kernel-hal/src/libos/drivers.rs

@@ -1,9 +1,11 @@
 use alloc::boxed::Box;
 
 use zcore_drivers::mock::MockUart;
+use zcore_drivers::scheme::EventListener;
 
 use crate::drivers::UART;
 
 pub(super) fn init() {
-    UART.init_by(Box::new(MockUart::new()));
+    UART.init_by(Box::new(EventListener::new(MockUart::new())));
+    MockUart::start_irq_serve(|| UART.handle_irq(0));
 }

kernel-hal/src/libos/mem_common.rs

@@ -10,7 +10,7 @@ use crate::{mem::phys_to_virt, VirtAddr, PAGE_SIZE};
 pub(super) const PMEM_BASE: VirtAddr = 0x8_0000_0000;
 pub(super) const PMEM_SIZE: usize = 0x4000_0000; // 1GiB
 
-lazy_static::lazy_static! {
+lazy_static! {
     pub(super) static ref FRAME_FILE: File = create_pmem_file();
     pub(super) static ref AVAILABLE_FRAMES: Mutex<VecDeque<usize>> =
         Mutex::new((PAGE_SIZE..PMEM_SIZE).step_by(PAGE_SIZE).collect());

kernel-hal/src/libos/mod.rs

@@ -38,10 +38,4 @@ pub fn init() {
     unsafe {
         register_sigsegv_handler();
     }
-    // spawn a thread to read stdin
-    // TODO: raw mode
-    std::thread::spawn(|| loop {
-        crate::serial::handle_irq();
-        core::hint::spin_loop();
-    });
 }

linux-loader/src/lib.rs

@@ -56,8 +56,7 @@ pub fn run(args: Vec<String>, envs: Vec<String>, rootfs: Arc<dyn FileSystem>) ->
     let path = args[0].clone();
     debug!("Linux process: {:?}", path);
 
-    use kernel_hal::vm::{GenericPageTable, PageTable};
-    let pg_token = PageTable::from_current().table_phys();
+    let pg_token = kernel_hal::vm::current_vmtoken();
     debug!("current pgt = {:#x}", pg_token);
     //调用zircon-object/src/task/thread.start设置好要执行的thread
     let (entry, sp) = loader.load(&proc.vmar(), &data, args, envs, path).unwrap();
@@ -96,7 +95,7 @@ async fn new_thread(thread: CurrentThread) {
             0x20..=0x3f => {
                 kernel_hal::interrupt::handle_irq(cx.trap_num as u32);
                 if cx.trap_num == 0x20 {
-                    kernel_hal::future::yield_now().await;
+                    kernel_hal::thread::yield_now().await;
                 }
             }
             0xe => {
@@ -133,7 +132,7 @@ async fn new_thread(thread: CurrentThread) {
                         if trap_num == 4 || trap_num == 5 {
                             debug!("Timer interrupt: {}", trap_num);
 
-                            kernel_hal::future::yield_now().await;
+                            kernel_hal::thread::yield_now().await;
                         }
 
                         //kernel_hal::interrupt::handle_irq(trap_num as u32);

linux-loader/src/main.rs

@@ -21,16 +21,18 @@ async fn main() {
         kernel_hal::dev::fb::init();
         kernel_hal::dev::input::init();
     }
-    kernel_hal::serial::serial_set_callback(Box::new({
-        move || {
-            let mut buffer = [0; 255];
-            let len = kernel_hal::serial::serial_read(&mut buffer);
-            for c in &buffer[..len] {
-                STDIN.push((*c).into());
+
+    use kernel_hal::drivers::UART;
+    UART.subscribe(
+        Box::new(|_| {
+            while let Some(c) = UART.try_recv().unwrap() {
+                let c = if c == b'\r' { b'\n' } else { c };
+                STDIN.push(c as char);
             }
-            false
-        }
-    }));
+        }),
+        false,
+    );
+
     // run first process
     let args: Vec<_> = std::env::args().skip(1).collect();
     let envs = vec!["PATH=/usr/sbin:/usr/bin:/sbin:/bin:/usr/x86_64-alpine-linux-musl/bin".into()];

linux-syscall/src/task.rs

@@ -297,7 +297,7 @@ impl Syscall<'_> {
     pub async fn sys_nanosleep(&self, req: UserInPtr<TimeSpec>) -> SysResult {
         info!("nanosleep: deadline={:?}", req);
         let req = req.read()?;
-        kernel_hal::future::sleep_until(req.into()).await;
+        kernel_hal::thread::sleep_until(req.into()).await;
         Ok(0)
     }
 

zCore/src/main.rs

@@ -167,19 +167,18 @@ fn get_rootproc(cmdline: &str) -> Vec<String> {
 
 #[cfg(feature = "linux")]
 fn main(ramfs_data: &'static mut [u8], cmdline: &str) -> ! {
+    use kernel_hal::drivers::UART;
     use linux_object::fs::STDIN;
 
-    kernel_hal::serial::serial_set_callback(Box::new({
-        move || {
-            let mut buffer = [0; 255];
-            let len = kernel_hal::serial::serial_read(&mut buffer);
-            for c in &buffer[..len] {
-                STDIN.push((*c).into());
-                // kernel_hal::serial::serial_write(alloc::format!("{}", *c as char).as_str());
+    UART.subscribe(
+        Box::new(|_| {
+            while let Some(c) = UART.try_recv().unwrap() {
+                let c = if c == b'\r' { b'\n' } else { c };
+                STDIN.push(c as char);
             }
-            false
-        }
-    }));
+        }),
+        false,
+    );
 
     //let args: Vec<String> = vec!["/bin/busybox".into(), "sh".into()];
     let args: Vec<String> = get_rootproc(cmdline);
@@ -234,6 +233,9 @@ impl KernelHandler for ZcoreKernelHandler {
     }
 
     fn handle_page_fault(&self, fault_vaddr: usize, access_flags: MMUFlags) {
-        panic!("page fault from kernel mode @ {:#x}({:?})", fault_vaddr, access_flags);
+        panic!(
+            "page fault from kernel mode @ {:#x}({:?})",
+            fault_vaddr, access_flags
+        );
     }
 }

zircon-loader/src/lib.rs

@@ -220,7 +220,7 @@ async fn new_thread(thread: CurrentThread) {
                 kernel_hal::interrupt::handle_irq(trap_num as u32);
                 if trap_num == 0x20 {
                     EXCEPTIONS_TIMER.add(1);
-                    kernel_hal::future::yield_now().await;
+                    kernel_hal::thread::yield_now().await;
                 }
             }
             0xe => {

zircon-object/src/task/thread.rs

@@ -15,7 +15,6 @@ use {
     },
     futures::{channel::oneshot::*, future::FutureExt, pin_mut, select_biased},
     kernel_hal::context::{GeneralRegs, UserContext},
-    // kernel_hal::future::sleep_until,
     spin::Mutex,
 };
 
@@ -603,14 +602,14 @@ impl CurrentThread {
             select_biased! {
                 ret = future.fuse() => ret.into_result(),
                 _ = killed.fuse() => Err(ZxError::STOP),
-                _ = kernel_hal::future::sleep_until(deadline).fuse() => Err(ZxError::TIMED_OUT),
+                _ = kernel_hal::thread::sleep_until(deadline).fuse() => Err(ZxError::TIMED_OUT),
                 _ = cancel_token.fuse() => Err(ZxError::CANCELED),
             }
         } else {
             select_biased! {
                 ret = future.fuse() => ret.into_result(),
                 _ = killed.fuse() => Err(ZxError::STOP),
-                _ = kernel_hal::future::sleep_until(deadline).fuse() => Err(ZxError::TIMED_OUT),
+                _ = kernel_hal::thread::sleep_until(deadline).fuse() => Err(ZxError::TIMED_OUT),
             }
         };
         let mut inner = self.inner.lock();

zircon-syscall/src/debug.rs

@@ -25,15 +25,10 @@ impl Syscall<'_> {
         let proc = self.thread.proc();
         proc.get_object::<Resource>(handle)?
             .validate(ResourceKind::ROOT)?;
-        // FIXME: To make 'console' work, now debug_read is a blocking call.
-        //        But it should be non-blocking.
-        // let mut vec = vec![0u8; buf_size as usize];
-        // let len = kernel_hal::serial_read(&mut vec);
-        // buf.write_array(&vec[..len])?;
-        // actual.write(len as u32)?;
-        let c = kernel_hal::future::serial_getchar().await;
-        buf.write_array(&[c])?;
-        actual.write(1)?;
+        let mut vec = vec![0u8; buf_size as usize];
+        let len = kernel_hal::serial::serial_read(&mut vec).await;
+        buf.write_array(&vec[..len])?;
+        actual.write(len as u32)?;
         Ok(())
     }
 }

zircon-syscall/src/time.rs

@@ -94,11 +94,13 @@ impl Syscall<'_> {
     pub async fn sys_nanosleep(&self, deadline: Deadline) -> ZxResult {
         info!("nanosleep: deadline={:?}", deadline);
         if deadline.0 <= 0 {
-            kernel_hal::future::yield_now().await;
+            kernel_hal::thread::yield_now().await;
         } else {
+            let future = kernel_hal::thread::sleep_until(deadline.into());
+            pin_mut!(future);
             self.thread
                 .blocking_run(
-                    kernel_hal::future::sleep_until(deadline.into()),
+                    future,
                     ThreadState::BlockedSleeping,
                     Deadline::forever().into(),
                     None,