diff --git a/.cargo/config.toml b/.cargo/config.toml
deleted file mode 100644
index 6a5ba74..0000000
--- a/.cargo/config.toml
+++ /dev/null
@@ -1,2 +0,0 @@
-[build]
-target = "riscv64gc-unknown-none-elf"
\ No newline at end of file
diff --git a/Cargo.lock b/Cargo.lock
deleted file mode 100644
index 5159e80..0000000
--- a/Cargo.lock
+++ /dev/null
@@ -1,7 +0,0 @@
-# This file is automatically @generated by Cargo.
-# It is not intended for manual editing.
-version = 3
-
-[[package]]
-name = "os"
-version = "0.1.0"
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..f288702
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
+ GNU GENERAL PUBLIC LICENSE
+ Version 3, 29 June 2007
+
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+
+ IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+ Copyright (C)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ Copyright (C)
+ This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+ This is free software, and you are welcome to redistribute it
+ under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+.
+
+ The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..8592b91
--- /dev/null
+++ b/README.md
@@ -0,0 +1,25 @@
+# rCore Exercises
+
+## Build
+
+### in dir `user`
+
+``` bash
+cargo build --release
+rust-objcopy --strip-all target/riscv64gc-unknown-none-elf/release/00_hello_world -O binary target/riscv64gc-unknown-none-elf/release/00_hello_world.bin
+...
+```
+
+### in dir `os`
+
+``` bash
+LOG=TRACE cargo build --release
+```
+
+## Run
+
+rustsbi-qemu should be downloaded manually.
+
+``` bash
+qemu-system-riscv64 -machine virt -nographic -bios target/riscv64gc-unknown-none-elf/release/rustsbi-qemu.bin -device loader,file=target/riscv64gc-unknown-none-elf/release/os
+```
\ No newline at end of file
diff --git a/os/.cargo/config.toml b/os/.cargo/config.toml
new file mode 100644
index 0000000..6ddcd53
--- /dev/null
+++ b/os/.cargo/config.toml
@@ -0,0 +1,7 @@
+[build]
+target = "riscv64gc-unknown-none-elf"
+
+[target.riscv64gc-unknown-none-elf]
+rustflags = [
+ "-Clink-arg=-Tsrc/linker.ld", "-Cforce-frame-pointers=yes"
+]
\ No newline at end of file
diff --git a/.gitignore b/os/.gitignore
similarity index 100%
rename from .gitignore
rename to os/.gitignore
diff --git a/os/Cargo.lock b/os/Cargo.lock
new file mode 100644
index 0000000..ba98085
--- /dev/null
+++ b/os/Cargo.lock
@@ -0,0 +1,132 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "critical-section"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "790eea4361631c5e7d22598ecd5723ff611904e3344ce8720784c93e3d83d40b"
+
+[[package]]
+name = "embedded-hal"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "361a90feb7004eca4019fb28352a9465666b24f840f5c3cddf0ff13920590b89"
+
+[[package]]
+name = "lazy_static"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bbd2bcb4c963f2ddae06a2efc7e9f3591312473c50c6685e1f298068316e66fe"
+dependencies = [
+ "spin",
+]
+
+[[package]]
+name = "log"
+version = "0.4.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7a70ba024b9dc04c27ea2f0c0548feb474ec5c54bba33a7f72f873a39d07b24"
+
+[[package]]
+name = "os"
+version = "0.1.0"
+dependencies = [
+ "lazy_static",
+ "log",
+ "riscv",
+ "sbi-rt",
+]
+
+[[package]]
+name = "paste"
+version = "1.0.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "57c0d7b74b563b49d38dae00a0c37d4d6de9b432382b2892f0574ddcae73fd0a"
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.89"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f139b0662de085916d1fb67d2b4169d1addddda1919e696f3252b740b629986e"
+dependencies = [
+ "unicode-ident",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b5b9d34b8991d19d98081b46eacdd8eb58c6f2b201139f7c5f643cc155a633af"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "riscv"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5ea8ff73d3720bdd0a97925f0bf79ad2744b6da8ff36be3840c48ac81191d7a7"
+dependencies = [
+ "critical-section",
+ "embedded-hal",
+ "paste",
+ "riscv-macros",
+ "riscv-pac",
+]
+
+[[package]]
+name = "riscv-macros"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f265be5d634272320a7de94cea15c22a3bfdd4eb42eb43edc528415f066a1f25"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "riscv-pac"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8188909339ccc0c68cfb5a04648313f09621e8b87dc03095454f1a11f6c5d436"
+
+[[package]]
+name = "sbi-rt"
+version = "0.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7fbaa69be1eedc61c426e6d489b2260482e928b465360576900d52d496a58bd0"
+dependencies = [
+ "sbi-spec",
+]
+
+[[package]]
+name = "sbi-spec"
+version = "0.0.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6e36312fb5ddc10d08ecdc65187402baba4ac34585cb9d1b78522ae2358d890"
+
+[[package]]
+name = "spin"
+version = "0.9.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6980e8d7511241f8acf4aebddbb1ff938df5eebe98691418c4468d0b72a96a67"
+
+[[package]]
+name = "syn"
+version = "2.0.87"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25aa4ce346d03a6dcd68dd8b4010bcb74e54e62c90c573f394c46eae99aba32d"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
+[[package]]
+name = "unicode-ident"
+version = "1.0.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e91b56cd4cadaeb79bbf1a5645f6b4f8dc5bde8834ad5894a8db35fda9efa1fe"
diff --git a/os/Cargo.toml b/os/Cargo.toml
new file mode 100644
index 0000000..d7dfdfb
--- /dev/null
+++ b/os/Cargo.toml
@@ -0,0 +1,10 @@
+[package]
+name = "os"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+lazy_static = { version = "1.5.0", features = ["spin_no_std"] }
+log = "0.4.22"
+riscv = "0.12.1"
+sbi-rt = "0.0.3"
diff --git a/os/src/batch.rs b/os/src/batch.rs
new file mode 100644
index 0000000..cf243f3
--- /dev/null
+++ b/os/src/batch.rs
@@ -0,0 +1,135 @@
+use core::{arch::asm, mem, slice};
+
+use lazy_static::*;
+use log::info;
+
+use crate::{sbi::shutdown, sync::UPSafeCell, trap::TrapContext};
+
+const KERNEL_STACK_SIZE: usize = 4096 * 2;
+const USER_STACK_SIZE: usize = 4096 * 2;
+const MAX_APP_NUM: usize = 16;
+const APP_BASE_ADDRESS: usize = 0x80400000;
+const APP_SIZE_LIMIT: usize = 0x20000;
+
+#[repr(align(4096))]
+struct KernelStack {
+ data: [u8; KERNEL_STACK_SIZE],
+}
+#[repr(align(4096))]
+struct UserStack {
+ data: [u8; USER_STACK_SIZE],
+}
+
+static KERNEL_STACK: KernelStack = KernelStack {
+ data: [0; KERNEL_STACK_SIZE],
+};
+static USER_STACK: UserStack = UserStack {
+ data: [0; USER_STACK_SIZE],
+};
+
+impl KernelStack {
+ fn get_sp(&self) -> usize {
+ self.data.as_ptr() as usize + KERNEL_STACK_SIZE
+ }
+
+ pub fn push_context(&self, cx: TrapContext) -> &'static mut TrapContext {
+ let cx_ptr = (self.get_sp() - mem::size_of::()) as *mut TrapContext;
+ unsafe {
+ *cx_ptr = cx;
+ }
+ unsafe { cx_ptr.as_mut().unwrap() }
+ }
+}
+
+impl UserStack {
+ fn get_sp(&self) -> usize {
+ self.data.as_ptr() as usize + USER_STACK_SIZE
+ }
+}
+
+struct AppManager {
+ num_app: usize,
+ current_app: usize,
+ app_start: [usize; MAX_APP_NUM + 1],
+}
+
+impl AppManager {
+ pub fn print_app_info(&self) {
+ info!(target: "kernel", "num_app = {}", self.num_app);
+ for i in 0..self.num_app {
+ info!(target: "kernel", "app_{} [{:#x}, {:#x}]", i, self.app_start[i], self.app_start[i + 1]);
+ }
+ }
+
+ pub fn get_current_app(&self) -> usize {
+ self.current_app
+ }
+
+ pub fn move_to_next_app(&mut self) {
+ self.current_app += 1;
+ }
+
+ unsafe fn load_app(&self, app_id: usize) {
+ if app_id >= self.num_app {
+ info!(target: "kernel", "All applications completed");
+ shutdown(false);
+ }
+ info!(target: "kernel", "Loading app_{}", app_id);
+
+ slice::from_raw_parts_mut(APP_BASE_ADDRESS as *mut u8, APP_SIZE_LIMIT).fill(0);
+ let app_src = slice::from_raw_parts(self.app_start[app_id] as *const u8, self.app_start[app_id + 1] - self.app_start[app_id]);
+ let app_dst = slice::from_raw_parts_mut(APP_BASE_ADDRESS as *mut u8, app_src.len());
+ app_dst.copy_from_slice(app_src);
+ asm!("fence.i");
+ }
+}
+
+lazy_static! {
+ static ref APP_MANAGER: UPSafeCell = unsafe {
+ UPSafeCell::new({
+ extern "C" {
+ fn _num_app();
+ }
+
+ let num_app_ptr = _num_app as usize as *const usize;
+ let num_app = num_app_ptr.read_volatile();
+ let mut app_start: [usize; MAX_APP_NUM + 1] = [0; MAX_APP_NUM + 1];
+ let app_start_raw: &[usize] = slice::from_raw_parts(num_app_ptr.add(1), num_app + 1);
+ app_start[..=num_app].copy_from_slice(app_start_raw);
+ AppManager {
+ num_app,
+ current_app: 0,
+ app_start,
+ }
+ })
+ };
+}
+
+pub fn init() {
+ print_app_info();
+}
+
+pub fn print_app_info() {
+ APP_MANAGER.exclusive_access().print_app_info();
+}
+
+pub fn run_next_app() -> ! {
+ let mut app_manager = APP_MANAGER.exclusive_access();
+ let current_app = app_manager.get_current_app();
+ unsafe {
+ app_manager.load_app(current_app);
+ }
+ app_manager.move_to_next_app();
+ drop(app_manager);
+
+ extern "C" {
+ fn __restore(cx_addr: usize);
+ }
+ unsafe {
+ __restore(KERNEL_STACK.push_context(TrapContext::app_init_context(
+ APP_BASE_ADDRESS,
+ USER_STACK.get_sp(),
+ )) as *const _ as usize);
+ }
+ panic!("Unreachable in batch::run_current_app");
+}
\ No newline at end of file
diff --git a/os/src/console.rs b/os/src/console.rs
new file mode 100644
index 0000000..00aa650
--- /dev/null
+++ b/os/src/console.rs
@@ -0,0 +1,29 @@
+use core::fmt::{self, Write};
+use crate::sbi;
+
+struct Stdout;
+
+impl Write for Stdout {
+ fn write_str(&mut self, s: &str) -> core::fmt::Result {
+ sbi::console_write(s.as_bytes());
+ Ok(())
+ }
+}
+
+pub fn print(args: fmt::Arguments) {
+ Stdout.write_fmt(args).unwrap();
+}
+
+#[macro_export]
+macro_rules! print {
+ ($fmt: literal $(, $($arg: tt)+)?) => {
+ $crate::console::print(format_args!($fmt $(, $($arg)+)?));
+ };
+}
+
+#[macro_export]
+macro_rules! println {
+ ($fmt: literal $(, $($arg: tt)+)?) => {
+ $crate::console::print(format_args!(concat!($fmt, "\n") $(, $($arg)+)?));
+ };
+}
\ No newline at end of file
diff --git a/os/src/entry.asm b/os/src/entry.asm
new file mode 100644
index 0000000..bf1f801
--- /dev/null
+++ b/os/src/entry.asm
@@ -0,0 +1,12 @@
+ .section .text.entry
+ .globl _start
+_start:
+ la sp, boot_start_top
+ call rust_main
+
+ .section .bss.stack
+ .globl boot_stack_lower_bound
+boot_stack_lower_bound:
+ .space 4096 * 16
+ .globl boot_start_top
+boot_start_top:
\ No newline at end of file
diff --git a/os/src/lang_items.rs b/os/src/lang_items.rs
new file mode 100644
index 0000000..482328e
--- /dev/null
+++ b/os/src/lang_items.rs
@@ -0,0 +1,18 @@
+use core::panic::PanicInfo;
+use crate::{sbi, println};
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+ let err = info.message().as_str().unwrap();
+ if let Some(location) = info.location() {
+ println!(
+ "Panicked at {}:{} {}",
+ location.file(),
+ location.line(),
+ err
+ );
+ } else {
+ println!("Panicked: {}", err);
+ }
+ sbi::shutdown(true)
+}
\ No newline at end of file
diff --git a/os/src/link_app.S b/os/src/link_app.S
new file mode 100644
index 0000000..c55d8e3
--- /dev/null
+++ b/os/src/link_app.S
@@ -0,0 +1,47 @@
+
+ .align 3
+ .section .data
+ .global _num_app
+_num_app:
+ .quad 5
+ .quad app_0_start
+ .quad app_1_start
+ .quad app_2_start
+ .quad app_3_start
+ .quad app_4_start
+ .quad app_4_end
+
+ .section .data
+ .global app_0_start
+ .global app_0_end
+app_0_start:
+ .incbin "../user/target/riscv64gc-unknown-none-elf/release/00_hello_world.bin"
+app_0_end:
+
+ .section .data
+ .global app_1_start
+ .global app_1_end
+app_1_start:
+ .incbin "../user/target/riscv64gc-unknown-none-elf/release/01_store_fault.bin"
+app_1_end:
+
+ .section .data
+ .global app_2_start
+ .global app_2_end
+app_2_start:
+ .incbin "../user/target/riscv64gc-unknown-none-elf/release/02_power.bin"
+app_2_end:
+
+ .section .data
+ .global app_3_start
+ .global app_3_end
+app_3_start:
+ .incbin "../user/target/riscv64gc-unknown-none-elf/release/03_priv_inst.bin"
+app_3_end:
+
+ .section .data
+ .global app_4_start
+ .global app_4_end
+app_4_start:
+ .incbin "../user/target/riscv64gc-unknown-none-elf/release/04_priv_csr.bin"
+app_4_end:
diff --git a/os/src/linker.ld b/os/src/linker.ld
new file mode 100644
index 0000000..02d26c6
--- /dev/null
+++ b/os/src/linker.ld
@@ -0,0 +1,48 @@
+OUTPUT_ARCH(riscv)
+ENTRY(_start)
+BASE_ADDRESS = 0x80200000;
+
+SECTIONS
+{
+ . = BASE_ADDRESS;
+ skernel = .;
+
+ stext = .;
+ .text : {
+ *(.text.entry)
+ *(.text .text.*)
+ }
+
+ . = ALIGN(4K);
+ etext = .;
+ srodata = .;
+ .rodata : {
+ *(.data .rodata.*)
+ *(.srodata .srodata.*)
+ }
+
+ . = ALIGN(4K);
+ erodata = .;
+ sdata = .;
+ .data : {
+ *(.data .data.*)
+ *(.sdata .sdata.*)
+ }
+
+ . = ALIGN(4K);
+ edata = .;
+ .bss : {
+ *(.bss.stack)
+ sbss = .;
+ *(.bss .bss.*)
+ *(.sbss .sbss.*)
+ }
+
+ . = ALIGN(4K);
+ ebss = .;
+ ekernel = .;
+
+ /DISCARD/ : {
+ *(.eh_frame)
+ }
+}
\ No newline at end of file
diff --git a/os/src/logger.rs b/os/src/logger.rs
new file mode 100644
index 0000000..5b720e7
--- /dev/null
+++ b/os/src/logger.rs
@@ -0,0 +1,42 @@
+use log::{Level, LevelFilter, Log};
+
+use crate::println;
+
+struct Logger;
+
+impl Log for Logger {
+ fn enabled(&self, _metadata: &log::Metadata) -> bool {
+ true
+ }
+
+ fn log(&self, record: &log::Record) {
+ if !self.enabled(record.metadata()) {
+ return;
+ }
+
+ let (color, level) = match record.level() {
+ Level::Error => (31, "ERR"),
+ Level::Warn => (93, "WRN"),
+ Level::Info => (34, "INF"),
+ Level::Debug => (32, "DBG"),
+ Level::Trace => (90, "TRC"),
+ };
+
+ println!("\x1b[{}m{}\x1b[0m \x1b[1m{}\x1b[0m {}", color, level, record.target(), record.args());
+ }
+
+ fn flush(&self) {}
+}
+
+pub fn init() {
+ static LOGGER: Logger = Logger;
+ log::set_logger(&LOGGER).unwrap();
+ log::set_max_level(match option_env!("LOG") {
+ Some("ERROR") => LevelFilter::Error,
+ Some("WARN") => LevelFilter::Warn,
+ Some("INFO") => LevelFilter::Info,
+ Some("DEBUG") => LevelFilter::Debug,
+ Some("TRACE") => LevelFilter::Trace,
+ _ => LevelFilter::Off,
+ });
+}
\ No newline at end of file
diff --git a/os/src/main.rs b/os/src/main.rs
new file mode 100644
index 0000000..0268870
--- /dev/null
+++ b/os/src/main.rs
@@ -0,0 +1,73 @@
+#![no_std]
+#![no_main]
+
+mod lang_items;
+mod sbi;
+mod logger;
+
+#[macro_use]
+mod console;
+
+mod batch;
+mod sync;
+mod trap;
+mod syscall;
+
+use core::arch::global_asm;
+use log::{debug, error, info, trace, warn};
+
+global_asm!(include_str!("entry.asm"));
+global_asm!(include_str!("link_app.S"));
+
+#[no_mangle]
+pub fn rust_main() -> ! {
+ clear_bss();
+ logger::init();
+
+ print_system_info();
+ print_to_console();
+
+ trap::init();
+ batch::init();
+ batch::run_next_app();
+}
+
+fn clear_bss() {
+ extern "C" {
+ fn sbss();
+ fn ebss();
+ }
+ (sbss as usize..ebss as usize).for_each(|a| {
+ unsafe { (a as *mut u8).write_volatile(0) }
+ });
+}
+
+fn print_to_console() {
+ sbi::console_write_byte('O' as u8);
+ sbi::console_write_byte('K' as u8);
+ sbi::console_write_byte('\n' as u8);
+
+ trace!("Hello World.");
+ debug!("Hello World.");
+ info!("Hello World.");
+ warn!("Hello World.");
+ error!("Hello World.");
+}
+
+fn print_system_info() {
+ extern "C" {
+ fn stext();
+ fn etext();
+ fn sdata();
+ fn edata();
+ fn srodata();
+ fn erodata();
+ fn sbss();
+ fn ebss();
+ }
+
+ info!(".text [{:#x}, {:#x}]", stext as usize, etext as usize);
+ info!(".rodata [{:#x}, {:#x}]", srodata as usize, erodata as usize);
+ info!(".data [{:#x}, {:#x}]", sdata as usize, edata as usize);
+ info!(".bss [{:#x}, {:#x}]", sbss as usize, ebss as usize);
+}
\ No newline at end of file
diff --git a/os/src/sbi.rs b/os/src/sbi.rs
new file mode 100644
index 0000000..ad5f72f
--- /dev/null
+++ b/os/src/sbi.rs
@@ -0,0 +1,19 @@
+pub fn console_write_byte(c: u8) {
+ sbi_rt::console_write_byte(c);
+}
+
+pub fn console_write(bytes: &[u8]) {
+ let range = bytes.as_ptr_range();
+ let bytes = sbi_rt::Physical::new(bytes.len(), range.start as usize, range.end as usize);
+ sbi_rt::console_write(bytes);
+}
+
+pub fn shutdown(failure: bool) -> ! {
+ use sbi_rt::{system_reset, NoReason, Shutdown, SystemFailure};
+ if !failure {
+ system_reset(Shutdown, NoReason);
+ } else {
+ system_reset(Shutdown, SystemFailure);
+ }
+ unreachable!()
+}
\ No newline at end of file
diff --git a/os/src/sync/mod.rs b/os/src/sync/mod.rs
new file mode 100644
index 0000000..7729524
--- /dev/null
+++ b/os/src/sync/mod.rs
@@ -0,0 +1,3 @@
+mod up;
+
+pub use up::UPSafeCell;
\ No newline at end of file
diff --git a/os/src/sync/up.rs b/os/src/sync/up.rs
new file mode 100644
index 0000000..8ace25a
--- /dev/null
+++ b/os/src/sync/up.rs
@@ -0,0 +1,18 @@
+use core::cell::{RefCell, RefMut};
+
+pub struct UPSafeCell {
+ inner: RefCell
+}
+
+unsafe impl Sync for UPSafeCell {}
+
+impl UPSafeCell {
+ pub unsafe fn new(value: T) -> Self {
+ Self {
+ inner: RefCell::new(value)
+ }
+ }
+ pub fn exclusive_access(&self) -> RefMut<'_, T> {
+ self.inner.borrow_mut()
+ }
+}
\ No newline at end of file
diff --git a/os/src/syscall/fs.rs b/os/src/syscall/fs.rs
new file mode 100644
index 0000000..453febd
--- /dev/null
+++ b/os/src/syscall/fs.rs
@@ -0,0 +1,17 @@
+use core::{slice, str};
+
+const FD_STDOUT: usize = 1;
+
+pub fn sys_write(fd: usize, buf: *const u8, len: usize) -> isize {
+ match fd {
+ FD_STDOUT => {
+ let slice = unsafe { slice::from_raw_parts(buf, len) };
+ let str = str::from_utf8(slice).unwrap();
+ print!("{}", str);
+ len as isize
+ }
+ _ => {
+ panic!("Unsupported fd in sys_write!");
+ }
+ }
+}
\ No newline at end of file
diff --git a/os/src/syscall/mod.rs b/os/src/syscall/mod.rs
new file mode 100644
index 0000000..5be165c
--- /dev/null
+++ b/os/src/syscall/mod.rs
@@ -0,0 +1,16 @@
+use fs::sys_write;
+use process::sys_exit;
+
+const SYSCALL_WRITE: usize = 64;
+const SYSCALL_EXIT: usize = 93;
+
+mod fs;
+mod process;
+
+pub fn syscall(syscall_id: usize, args: [usize; 3]) -> isize {
+ match syscall_id {
+ SYSCALL_WRITE => sys_write(args[0], args[1] as *const u8, args[2]),
+ SYSCALL_EXIT => sys_exit(args[0] as i32),
+ _ => panic!("Unsupported syscall_id: {}", syscall_id)
+ }
+}
\ No newline at end of file
diff --git a/os/src/syscall/process.rs b/os/src/syscall/process.rs
new file mode 100644
index 0000000..b93fa4d
--- /dev/null
+++ b/os/src/syscall/process.rs
@@ -0,0 +1,8 @@
+use log::info;
+
+use crate::batch::run_next_app;
+
+pub fn sys_exit(exit_code: i32) -> ! {
+ info!(target: "kernel", "Application exited with code {}", exit_code);
+ run_next_app()
+}
\ No newline at end of file
diff --git a/os/src/trap/context.rs b/os/src/trap/context.rs
new file mode 100644
index 0000000..6abbfd6
--- /dev/null
+++ b/os/src/trap/context.rs
@@ -0,0 +1,28 @@
+use riscv::register::sstatus::{self, Sstatus, SPP};
+
+#[repr(C)]
+pub struct TrapContext {
+ pub x: [usize; 32],
+ pub sstatus: Sstatus,
+ pub sepc: usize,
+}
+
+impl TrapContext {
+ pub fn set_sp(&mut self, sp: usize) {
+ self.x[2] = sp;
+ }
+
+ pub fn app_init_context(entry: usize, sp: usize) -> Self {
+ let cur_sstatus = sstatus::read();
+ unsafe {
+ sstatus::set_spp(SPP::User);
+ }
+ let mut cx = Self {
+ x: [0; 32],
+ sstatus: cur_sstatus,
+ sepc: entry,
+ };
+ cx.set_sp(sp);
+ cx
+ }
+}
\ No newline at end of file
diff --git a/os/src/trap/mod.rs b/os/src/trap/mod.rs
new file mode 100644
index 0000000..06b25b4
--- /dev/null
+++ b/os/src/trap/mod.rs
@@ -0,0 +1,44 @@
+mod context;
+pub use context::TrapContext;
+use log::error;
+
+use core::arch::global_asm;
+
+use riscv::{interrupt::{Exception, Trap}, register::{scause, stval, stvec::{self, TrapMode}}};
+
+use crate::{batch::run_next_app, syscall};
+
+global_asm!(include_str!("trap.S"));
+
+pub fn init() {
+ extern "C" {
+ fn __alltraps();
+ }
+ unsafe {
+ stvec::write(__alltraps as usize, TrapMode::Direct);
+ }
+}
+
+#[no_mangle]
+pub fn trap_handler(cx: &mut TrapContext) -> &mut TrapContext {
+ let scause = scause::read();
+ let stval = stval::read();
+ match scause.cause() {
+ Trap::Exception(e) if e == Exception::UserEnvCall as usize => {
+ cx.sepc += 4;
+ cx.x[10] = syscall::syscall(cx.x[17], [cx.x[10], cx.x[11], cx.x[12]]) as usize;
+ }
+ Trap::Exception(e) if e == Exception::StoreFault as usize || e == Exception::StorePageFault as usize => {
+ error!(target: "kernel", "PageFault in application, kernel killed it.");
+ run_next_app();
+ }
+ Trap::Exception(e) if e == Exception::IllegalInstruction as usize => {
+ error!(target: "kernel", "IllegalInstruction in application, kernel killed it.");
+ run_next_app();
+ }
+ _ => {
+ panic!("un supported strp {:?}, stval = {:#x}!", scause.cause(), stval);
+ }
+ }
+ cx
+}
\ No newline at end of file
diff --git a/os/src/trap/trap.S b/os/src/trap/trap.S
new file mode 100644
index 0000000..9d6967c
--- /dev/null
+++ b/os/src/trap/trap.S
@@ -0,0 +1,64 @@
+.altmacro
+.macro SAVE_GP n
+ sd x\n, \n*8(sp)
+.endm
+.macro LOAD_GP n
+ ld x\n, \n*8(sp)
+.endm
+ .section .text
+ .globl __alltraps
+ .globl __restore
+ .align 2
+__alltraps:
+ csrrw sp, sscratch, sp
+ # now sp->kernel stack, sscratch->user stack
+ # allocate a TrapContext on kernel stack
+ addi sp, sp, -34*8
+ # save general-purpose registers
+ sd x1, 1*8(sp)
+ # skip sp(x2), we will save it later
+ sd x3, 3*8(sp)
+ # skip tp(x4), application does not use it
+ # save x5~x31
+ .set n, 5
+ .rept 27
+ SAVE_GP %n
+ .set n, n+1
+ .endr
+ # we can use t0/t1/t2 freely, because they were saved on kernel stack
+ csrr t0, sstatus
+ csrr t1, sepc
+ sd t0, 32*8(sp)
+ sd t1, 33*8(sp)
+ # read user stack from sscratch and save it on the kernel stack
+ csrr t2, sscratch
+ sd t2, 2*8(sp)
+ # set input argument of trap_handler(cx: &mut TrapContext)
+ mv a0, sp
+ call trap_handler
+
+__restore:
+ # case1: start running app by __restore
+ # case2: back to U after handling trap
+ mv sp, a0
+ # now sp->kernel stack(after allocated), sscratch->user stack
+ # restore sstatus/sepc
+ ld t0, 32*8(sp)
+ ld t1, 33*8(sp)
+ ld t2, 2*8(sp)
+ csrw sstatus, t0
+ csrw sepc, t1
+ csrw sscratch, t2
+ # restore general-purpuse registers except sp/tp
+ ld x1, 1*8(sp)
+ ld x3, 3*8(sp)
+ .set n, 5
+ .rept 27
+ LOAD_GP %n
+ .set n, n+1
+ .endr
+ # release TrapContext on kernel stack
+ addi sp, sp, 34*8
+ # now sp->kernel stack, sscratch->user stack
+ csrrw sp, sscratch, sp
+ sret
diff --git a/src/lang_items.rs b/src/lang_items.rs
deleted file mode 100644
index a5f300c..0000000
--- a/src/lang_items.rs
+++ /dev/null
@@ -1,6 +0,0 @@
-use core::panic::PanicInfo;
-
-#[panic_handler]
-fn panic(_info: &PanicInfo) -> ! {
- loop {}
-}
\ No newline at end of file
diff --git a/src/main.rs b/src/main.rs
deleted file mode 100644
index f156fda..0000000
--- a/src/main.rs
+++ /dev/null
@@ -1,4 +0,0 @@
-#![no_std]
-#![no_main]
-
-mod lang_items;
diff --git a/user/.cargo/config.toml b/user/.cargo/config.toml
new file mode 100644
index 0000000..6ddcd53
--- /dev/null
+++ b/user/.cargo/config.toml
@@ -0,0 +1,7 @@
+[build]
+target = "riscv64gc-unknown-none-elf"
+
+[target.riscv64gc-unknown-none-elf]
+rustflags = [
+ "-Clink-arg=-Tsrc/linker.ld", "-Cforce-frame-pointers=yes"
+]
\ No newline at end of file
diff --git a/user/.gitignore b/user/.gitignore
new file mode 100644
index 0000000..ea8c4bf
--- /dev/null
+++ b/user/.gitignore
@@ -0,0 +1 @@
+/target
diff --git a/user/Cargo.lock b/user/Cargo.lock
new file mode 100644
index 0000000..287fb7a
--- /dev/null
+++ b/user/Cargo.lock
@@ -0,0 +1,93 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "critical-section"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "790eea4361631c5e7d22598ecd5723ff611904e3344ce8720784c93e3d83d40b"
+
+[[package]]
+name = "embedded-hal"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "361a90feb7004eca4019fb28352a9465666b24f840f5c3cddf0ff13920590b89"
+
+[[package]]
+name = "paste"
+version = "1.0.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "57c0d7b74b563b49d38dae00a0c37d4d6de9b432382b2892f0574ddcae73fd0a"
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.89"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f139b0662de085916d1fb67d2b4169d1addddda1919e696f3252b740b629986e"
+dependencies = [
+ "unicode-ident",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b5b9d34b8991d19d98081b46eacdd8eb58c6f2b201139f7c5f643cc155a633af"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "riscv"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5ea8ff73d3720bdd0a97925f0bf79ad2744b6da8ff36be3840c48ac81191d7a7"
+dependencies = [
+ "critical-section",
+ "embedded-hal",
+ "paste",
+ "riscv-macros",
+ "riscv-pac",
+]
+
+[[package]]
+name = "riscv-macros"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f265be5d634272320a7de94cea15c22a3bfdd4eb42eb43edc528415f066a1f25"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "riscv-pac"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8188909339ccc0c68cfb5a04648313f09621e8b87dc03095454f1a11f6c5d436"
+
+[[package]]
+name = "syn"
+version = "2.0.87"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "25aa4ce346d03a6dcd68dd8b4010bcb74e54e62c90c573f394c46eae99aba32d"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
+[[package]]
+name = "unicode-ident"
+version = "1.0.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e91b56cd4cadaeb79bbf1a5645f6b4f8dc5bde8834ad5894a8db35fda9efa1fe"
+
+[[package]]
+name = "user_lib"
+version = "0.1.0"
+dependencies = [
+ "riscv",
+]
diff --git a/Cargo.toml b/user/Cargo.toml
similarity index 63%
rename from Cargo.toml
rename to user/Cargo.toml
index aad338f..534e542 100644
--- a/Cargo.toml
+++ b/user/Cargo.toml
@@ -1,6 +1,7 @@
[package]
-name = "os"
+name = "user_lib"
version = "0.1.0"
edition = "2021"
[dependencies]
+riscv = "0.12.1"
diff --git a/user/src/bin/00_hello_world.rs b/user/src/bin/00_hello_world.rs
new file mode 100644
index 0000000..684396a
--- /dev/null
+++ b/user/src/bin/00_hello_world.rs
@@ -0,0 +1,11 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+
+#[no_mangle]
+fn main() -> i32 {
+ println!("Hello, world!");
+ 0
+}
\ No newline at end of file
diff --git a/user/src/bin/01_store_fault.rs b/user/src/bin/01_store_fault.rs
new file mode 100644
index 0000000..855f285
--- /dev/null
+++ b/user/src/bin/01_store_fault.rs
@@ -0,0 +1,15 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+
+#[no_mangle]
+fn main() -> i32 {
+ println!("Into Test store_fault, we will insert an invalid store operation...");
+ println!("kerne; should kill this application");
+ unsafe {
+ core::ptr::null_mut::().write_volatile(0);
+ }
+ 0
+}
\ No newline at end of file
diff --git a/user/src/bin/02_power.rs b/user/src/bin/02_power.rs
new file mode 100644
index 0000000..54fde24
--- /dev/null
+++ b/user/src/bin/02_power.rs
@@ -0,0 +1,27 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+
+const SIZE: usize = 10;
+const P: u32 = 3;
+const STEP: usize = 100000;
+const MOD: u32 = 10007;
+
+#[no_mangle]
+fn main() -> i32 {
+ let mut pow = [0u32; SIZE];
+ let mut index: usize = 0;
+ pow[index] = 1;
+ for i in 1..=STEP {
+ let last = pow[index];
+ index = (index + 1) % SIZE;
+ pow[index] = last * P % MOD;
+ if i % 10000 == 0 {
+ println!("{}^{}={}(MOD {})", P, i, pow[index], MOD);
+ }
+ }
+ println!("Test power OK!");
+ 0
+}
\ No newline at end of file
diff --git a/user/src/bin/03_priv_inst.rs b/user/src/bin/03_priv_inst.rs
new file mode 100644
index 0000000..04dac37
--- /dev/null
+++ b/user/src/bin/03_priv_inst.rs
@@ -0,0 +1,17 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+
+use core::arch::asm;
+
+#[no_mangle]
+fn main() -> i32 {
+ println!("Try to execute privileged instruction in U Mode");
+ println!("Kernel should kill this application!");
+ unsafe {
+ asm!("sret");
+ }
+ 0
+}
diff --git a/user/src/bin/04_priv_csr.rs b/user/src/bin/04_priv_csr.rs
new file mode 100644
index 0000000..fbd678f
--- /dev/null
+++ b/user/src/bin/04_priv_csr.rs
@@ -0,0 +1,17 @@
+#![no_std]
+#![no_main]
+
+#[macro_use]
+extern crate user_lib;
+
+use riscv::register::sstatus::{self, SPP};
+
+#[no_mangle]
+fn main() -> i32 {
+ println!("Try to access privileged CSR in U Mode");
+ println!("Kernel should kill this application!");
+ unsafe {
+ sstatus::set_spp(SPP::User);
+ }
+ 0
+}
diff --git a/user/src/console.rs b/user/src/console.rs
new file mode 100644
index 0000000..93e7255
--- /dev/null
+++ b/user/src/console.rs
@@ -0,0 +1,32 @@
+use super::write;
+use core::fmt::{self, Write};
+
+
+struct Stdout;
+
+const STDOUT: usize = 1;
+
+impl Write for Stdout {
+ fn write_str(&mut self, s: &str) -> fmt::Result {
+ write(STDOUT, s.as_bytes());
+ Ok(())
+ }
+}
+
+pub fn print(args: fmt::Arguments) {
+ Stdout.write_fmt(args).unwrap();
+}
+
+#[macro_export]
+macro_rules! print {
+ ($fmt: literal $(, $($arg: tt)+)?) => {
+ $crate::console::print(format_args!($fmt $(, $($arg)+)?));
+ }
+}
+
+#[macro_export]
+macro_rules! println {
+ ($fmt: literal $(, $($arg: tt)+)?) => {
+ $crate::console::print(format_args!(concat!($fmt, "\n") $(, $($arg)+)?));
+ }
+}
\ No newline at end of file
diff --git a/user/src/lang_items.rs b/user/src/lang_items.rs
new file mode 100644
index 0000000..afa93e2
--- /dev/null
+++ b/user/src/lang_items.rs
@@ -0,0 +1,17 @@
+use core::panic::PanicInfo;
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+ let err = info.message().as_str().unwrap();
+ if let Some(location) = info.location() {
+ println!(
+ "Panicked at {}:{}, {}",
+ location.file(),
+ location.line(),
+ err
+ );
+ } else {
+ println!("Panicked: {}", err);
+ }
+ loop {}
+}
\ No newline at end of file
diff --git a/user/src/lib.rs b/user/src/lib.rs
new file mode 100644
index 0000000..63bf15a
--- /dev/null
+++ b/user/src/lib.rs
@@ -0,0 +1,38 @@
+#![no_std]
+
+#[macro_use]
+pub mod console;
+mod syscall;
+mod lang_items;
+
+#[no_mangle]
+#[link_section = ".text.entry"]
+pub extern "C" fn _start() -> ! {
+ // linkage is not stable
+ // but main function in user function required
+ extern "C" {
+ fn main() -> i32;
+ }
+ clear_bss();
+ unsafe {
+ exit(main());
+ }
+ panic!("unreachable after sys_exit")
+}
+
+fn clear_bss() {
+ extern "C" {
+ fn sbss();
+ fn ebss();
+ }
+ (sbss as usize..ebss as usize).for_each(|addr| unsafe {
+ (addr as *mut u8).write_volatile(0);
+ });
+}
+
+pub fn write(fd: usize, buf: &[u8]) -> isize {
+ syscall::sys_write(fd, buf)
+}
+pub fn exit(exit_code: i32) -> isize {
+ syscall::sys_exit(exit_code)
+}
\ No newline at end of file
diff --git a/user/src/linker.ld b/user/src/linker.ld
new file mode 100644
index 0000000..01d13f2
--- /dev/null
+++ b/user/src/linker.ld
@@ -0,0 +1,46 @@
+OUTPUT_ARCH(riscv)
+ENTRY(_start)
+BASE_ADDRESS = 0x80400000;
+
+SECTIONS
+{
+ . = BASE_ADDRESS;
+
+ stext = .;
+ .text : {
+ *(.text.entry)
+ *(.text .text.*)
+ }
+
+ . = ALIGN(4K);
+ etext = .;
+ srodata = .;
+ .rodata : {
+ *(.data .rodata.*)
+ *(.srodata .srodata.*)
+ }
+
+ . = ALIGN(4K);
+ erodata = .;
+ sdata = .;
+ .data : {
+ *(.data .data.*)
+ *(.sdata .sdata.*)
+ }
+
+ . = ALIGN(4K);
+ edata = .;
+ .bss : {
+ *(.bss.stack)
+ sbss = .;
+ *(.bss .bss.*)
+ *(.sbss .sbss.*)
+ }
+
+ . = ALIGN(4K);
+ ebss = .;
+
+ /DISCARD/ : {
+ *(.eh_frame)
+ }
+}
\ No newline at end of file
diff --git a/user/src/syscall.rs b/user/src/syscall.rs
new file mode 100644
index 0000000..118cf83
--- /dev/null
+++ b/user/src/syscall.rs
@@ -0,0 +1,26 @@
+use core::arch::asm;
+
+const SYSCALL_WRITE: usize = 64;
+const SYSCALL_EXIT: usize = 93;
+
+fn syscall(id: usize, args: [usize; 3]) -> isize {
+ let mut ret: isize;
+ unsafe {
+ asm!(
+ "ecall",
+ inlateout("x10") args[0] => ret,
+ in("x11") args[1],
+ in("x12") args[2],
+ in("x17") id
+ );
+ }
+ ret
+}
+
+pub fn sys_write(fd: usize, buffer: &[u8]) -> isize {
+ syscall(SYSCALL_WRITE, [fd, buffer.as_ptr() as usize, buffer.len()])
+}
+
+pub fn sys_exit(exit_code: i32) -> isize {
+ syscall(SYSCALL_EXIT, [exit_code as usize, 0, 0])
+}
\ No newline at end of file