init version

.gitignore

@@ -0,0 +1,9 @@
+.idea
+Cargo.lock
+target
+os/src/link_app.S
+os/last-*
+user
+ci-user/
+tools
+workplace/

LICENSE

@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
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+
+  16. Limitation of Liability.
+
+  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.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    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 <https://www.gnu.org/licenses/>.
+
+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:
+
+    <program>  Copyright (C) <year>  <name of author>
+    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
+<https://www.gnu.org/licenses/>.
+
+  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
+<https://www.gnu.org/licenses/why-not-lgpl.html>.

Makefile

@@ -0,0 +1,58 @@
+DOCKER_NAME ?= dinghao188/rcore-tutorial
+DIR := workplace
+.PHONY: docker build_docker
+
+test: test3 test4 test5 test6 test7 test8
+
+setup:
+	rm -rf  ${DIR}
+	mkdir ${DIR}
+	cp -r easy-fs ${DIR}
+	cp -r easy-fs-fuse ${DIR}
+	cp -r ci-user ${DIR}
+	cp -r bootloader ${DIR}
+	cp -r reports ${DIR}
+	cp rust-toolchain ${DIR}
+
+test1: setup
+	cp -r os1 ${DIR}/os
+	cd ${DIR}/ci-user && make test CHAPTER=1
+
+
+test2: setup
+	cp -r os2 ${DIR}/os
+	cd ${DIR}/ci-user && make test CHAPTER=2
+
+test3: setup
+	cp -r os3 ${DIR}/os
+	cd ${DIR}/ci-user && make test CHAPTER=3
+
+test4: setup
+	cp -r os4 ${DIR}/os
+	cd ${DIR}/ci-user && make test CHAPTER=4
+
+test5: setup
+	cp -r os5 ${DIR}/os
+	cd ${DIR}/ci-user && make test CHAPTER=5
+
+test6: setup
+	cp -r os6 ${DIR}/os
+	cd ${DIR}/ci-user && make test CHAPTER=6
+
+test7: setup
+	cp -r os7 ${DIR}/os
+	cd ${DIR}/ci-user && make test CHAPTER=7
+
+test8: setup
+	cp -r os8 ${DIR}/os
+	cd ${DIR}/ci-user && make test CHAPTER=8
+
+clean:
+	rm -rf ${DIR}
+
+docker:
+	docker run --rm -it --mount type=bind,source=$(shell pwd),destination=/mnt ${DOCKER_NAME}
+
+build_docker: 
+	docker build -t ${DOCKER_NAME} .
+

easy-fs-fuse/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "easy-fs-fuse"
+version = "0.1.0"
+authors = ["Yifan Wu <shinbokuow@163.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+clap = "2.33.3"
+easy-fs = { path = "../easy-fs" }
+rand = "0.8.0"

easy-fs-fuse/src/main.rs

@@ -0,0 +1,155 @@
+use clap::{App, Arg};
+use easy_fs::{BlockDevice, EasyFileSystem};
+use std::fs::{read_dir, File, OpenOptions};
+use std::io::{Read, Seek, SeekFrom, Write};
+use std::sync::Arc;
+use std::sync::Mutex;
+
+/// Use a block size of 512 bytes
+const BLOCK_SZ: usize = 512;
+const BLOCK_NUM: usize = 16384;
+
+/// Wrapper for turning a File into a BlockDevice
+struct BlockFile(Mutex<File>);
+
+impl BlockDevice for BlockFile {
+    /// Read a block from file
+    fn read_block(&self, block_id: usize, buf: &mut [u8]) {
+        let mut file = self.0.lock().unwrap();
+        file.seek(SeekFrom::Start((block_id * BLOCK_SZ) as u64))
+            .expect("Error when seeking!");
+        assert_eq!(file.read(buf).unwrap(), BLOCK_SZ, "Not a complete block!");
+    }
+    /// Write a block into file
+    fn write_block(&self, block_id: usize, buf: &[u8]) {
+        let mut file = self.0.lock().unwrap();
+        file.seek(SeekFrom::Start((block_id * BLOCK_SZ) as u64))
+            .expect("Error when seeking!");
+        assert_eq!(file.write(buf).unwrap(), BLOCK_SZ, "Not a complete block!");
+    }
+}
+
+fn main() {
+    easy_fs_pack().expect("Error when packing easy-fs!");
+}
+
+/// Pack a directory into a easy-fs disk image
+fn easy_fs_pack() -> std::io::Result<()> {
+    let matches = App::new("EasyFileSystem packer")
+        .arg(
+            Arg::with_name("source")
+                .short("s")
+                .long("source")
+                .takes_value(true)
+                .help("Executable source dir(with backslash)"),
+        )
+        .arg(
+            Arg::with_name("target")
+                .short("t")
+                .long("target")
+                .takes_value(true)
+                .help("Executable target dir(with backslash)"),
+        )
+        .get_matches();
+    let src_path = matches.value_of("source").unwrap();
+    let target_path = matches.value_of("target").unwrap();
+    println!("src_path = {}\ntarget_path = {}", src_path, target_path);
+    let block_file = Arc::new(BlockFile(Mutex::new({
+        let f = OpenOptions::new()
+            .read(true)
+            .write(true)
+            .create(true)
+            .open(format!("{}{}", target_path, "fs.img"))?;
+        f.set_len((BLOCK_NUM * BLOCK_SZ) as u64).unwrap();
+        f
+    })));
+    let efs = EasyFileSystem::create(block_file.clone(), BLOCK_NUM as u32, 1);
+    let root_inode = Arc::new(EasyFileSystem::root_inode(&efs));
+    let apps: Vec<_> = read_dir(src_path)
+        .unwrap()
+        .into_iter()
+        .map(|dir_entry| {
+            let mut name_with_ext = dir_entry.unwrap().file_name().into_string().unwrap();
+            name_with_ext.drain(name_with_ext.find('.').unwrap()..name_with_ext.len());
+            name_with_ext
+        })
+        .collect();
+    for app in apps {
+        // load app data (elf) from host file system
+        let mut host_file = File::open(format!("{}{}", target_path, app)).unwrap();
+        let mut all_data: Vec<u8> = Vec::new();
+        host_file.read_to_end(&mut all_data).unwrap();
+        // create a file in easy-fs
+        let inode = root_inode.create(app.as_str()).unwrap();
+        // write data to easy-fs
+        inode.write_at(0, all_data.as_slice());
+    }
+    // list apps
+    for app in root_inode.ls() {
+        println!("{}", app);
+    }
+    Ok(())
+}
+
+#[test]
+fn efs_test() -> std::io::Result<()> {
+    let block_file = Arc::new(BlockFile(Mutex::new({
+        let f = OpenOptions::new()
+            .read(true)
+            .write(true)
+            .create(true)
+            .open("target/fs.img")?;
+        f.set_len(BLOCK_NUM * BLOCK_SZ).unwrap();
+        f
+    })));
+    EasyFileSystem::create(block_file.clone(), 4096, 1);
+    let efs = EasyFileSystem::open(block_file.clone());
+    let root_inode = EasyFileSystem::root_inode(&efs);
+    root_inode.create("filea");
+    root_inode.create("fileb");
+    for name in root_inode.ls() {
+        println!("{}", name);
+    }
+    let filea = root_inode.find("filea").unwrap();
+    let greet_str = "Hello, world!";
+    filea.write_at(0, greet_str.as_bytes());
+    //let mut buffer = [0u8; BLOCK_SZ];
+    let mut buffer = [0u8; 233];
+    let len = filea.read_at(0, &mut buffer);
+    assert_eq!(greet_str, core::str::from_utf8(&buffer[..len]).unwrap(),);
+
+    let mut random_str_test = |len: usize| {
+        filea.clear();
+        assert_eq!(filea.read_at(0, &mut buffer), 0,);
+        let mut str = String::new();
+        use rand;
+        // random digit
+        for _ in 0..len {
+            str.push(char::from('0' as u8 + rand::random::<u8>() % 10));
+        }
+        filea.write_at(0, str.as_bytes());
+        let mut read_buffer = [0u8; 127];
+        let mut offset = 0usize;
+        let mut read_str = String::new();
+        loop {
+            let len = filea.read_at(offset, &mut read_buffer);
+            if len == 0 {
+                break;
+            }
+            offset += len;
+            read_str.push_str(core::str::from_utf8(&read_buffer[..len]).unwrap());
+        }
+        assert_eq!(str, read_str);
+    };
+
+    random_str_test(4 * BLOCK_SZ);
+    random_str_test(8 * BLOCK_SZ + BLOCK_SZ / 2);
+    random_str_test(100 * BLOCK_SZ);
+    random_str_test(70 * BLOCK_SZ + BLOCK_SZ / 7);
+    random_str_test((12 + 128) * BLOCK_SZ);
+    random_str_test(400 * BLOCK_SZ);
+    random_str_test(1000 * BLOCK_SZ);
+    random_str_test(2000 * BLOCK_SZ);
+
+    Ok(())
+}

easy-fs/.gitignore

@@ -0,0 +1,3 @@
+.idea/
+target/
+Cargo.lock

easy-fs/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "easy-fs"
+version = "0.1.0"
+authors = ["Yifan Wu <shinbokuow@163.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+spin = "0.7.0"
+lazy_static = { version = "1.4.0", features = ["spin_no_std"] }

easy-fs/src/bitmap.rs

@@ -0,0 +1,77 @@
+use alloc::sync::Arc;
+use super::{
+    BlockDevice,
+    BLOCK_SZ,
+    get_block_cache,
+};
+
+/// A bitmap block
+type BitmapBlock = [u64; 64];
+
+/// Number of bits in a block
+const BLOCK_BITS: usize = BLOCK_SZ * 8;
+
+/// A bitmap
+pub struct Bitmap {
+    start_block_id: usize,
+    blocks: usize,
+}
+
+/// Decompose bits into (block_pos, bits64_pos, inner_pos)
+fn decomposition(mut bit: usize) -> (usize, usize, usize) {
+    let block_pos = bit / BLOCK_BITS;
+    bit = bit % BLOCK_BITS;
+    (block_pos, bit / 64, bit % 64)
+}
+
+impl Bitmap {
+    /// A new bitmap from start block id and number of blocks
+    pub fn new(start_block_id: usize, blocks: usize) -> Self {
+        Self {
+            start_block_id,
+            blocks,
+        }
+    }
+    /// Allocate a new block from a block device
+    pub fn alloc(&self, block_device: &Arc<dyn BlockDevice>) -> Option<usize> {
+        for block_id in 0..self.blocks {
+            let pos = get_block_cache(
+                block_id + self.start_block_id as usize,
+                Arc::clone(block_device),
+            ).lock().modify(0, |bitmap_block: &mut BitmapBlock| {
+                if let Some((bits64_pos, inner_pos)) = bitmap_block
+                    .iter()
+                    .enumerate()
+                    .find(|(_, bits64)| **bits64 != u64::MAX)
+                    .map(|(bits64_pos, bits64)| {
+                        (bits64_pos, bits64.trailing_ones() as usize)
+                    }) {
+                    // modify cache
+                    bitmap_block[bits64_pos] |= 1u64 << inner_pos;
+                    Some(block_id * BLOCK_BITS + bits64_pos * 64 + inner_pos as usize)
+                } else {
+                    None
+                }
+            });
+            if pos.is_some() {
+                return pos;
+            }
+        }
+        None
+    }
+    /// Deallocate a block
+    pub fn dealloc(&self, block_device: &Arc<dyn BlockDevice>, bit: usize) {
+        let (block_pos, bits64_pos, inner_pos) = decomposition(bit);
+        get_block_cache(
+            block_pos + self.start_block_id,
+            Arc::clone(block_device)
+        ).lock().modify(0, |bitmap_block: &mut BitmapBlock| {
+            assert!(bitmap_block[bits64_pos] & (1u64 << inner_pos) > 0);
+            bitmap_block[bits64_pos] -= 1u64 << inner_pos;
+        });
+    }
+    /// Get the max number of allocatable blocks
+    pub fn maximum(&self) -> usize {
+        self.blocks * BLOCK_BITS
+    }
+}

easy-fs/src/block_cache.rs

@@ -0,0 +1,144 @@
+use super::{
+    BLOCK_SZ,
+    BlockDevice,
+};
+use alloc::collections::VecDeque;
+use alloc::sync::Arc;
+use lazy_static::*;
+use spin::Mutex;
+
+/// Cached block inside memory
+pub struct BlockCache {
+    /// cached block data
+    cache: [u8; BLOCK_SZ],
+    /// underlying block id
+    block_id: usize,
+    /// underlying block device
+    block_device: Arc<dyn BlockDevice>,
+    /// whether the block is dirty
+    modified: bool,
+}
+
+impl BlockCache {
+    /// Load a new BlockCache from disk.
+    pub fn new(
+        block_id: usize,
+        block_device: Arc<dyn BlockDevice>
+    ) -> Self {
+        let mut cache = [0u8; BLOCK_SZ];
+        block_device.read_block(block_id, &mut cache);
+        Self {
+            cache,
+            block_id,
+            block_device,
+            modified: false,
+        }
+    }
+    /// Get the address of an offset inside the cached block data
+    fn addr_of_offset(&self, offset: usize) -> usize {
+        &self.cache[offset] as *const _ as usize
+    }
+
+    pub fn get_ref<T>(&self, offset: usize) -> &T where T: Sized {
+        let type_size = core::mem::size_of::<T>();
+        assert!(offset + type_size <= BLOCK_SZ);
+        let addr = self.addr_of_offset(offset);
+        unsafe { &*(addr as *const T) } 
+    }
+
+    pub fn get_mut<T>(&mut self, offset: usize) -> &mut T where T: Sized {
+        let type_size = core::mem::size_of::<T>();
+        assert!(offset + type_size <= BLOCK_SZ);
+        self.modified = true;
+        let addr = self.addr_of_offset(offset);
+        unsafe { &mut *(addr as *mut T) }
+    }
+
+    pub fn read<T, V>(&self, offset: usize, f: impl FnOnce(&T) -> V) -> V {
+        f(self.get_ref(offset))
+    }
+
+    pub fn modify<T, V>(&mut self, offset:usize, f: impl FnOnce(&mut T) -> V) -> V {
+        f(self.get_mut(offset))
+    }
+
+    pub fn sync(&mut self) {
+        if self.modified {
+            self.modified = false;
+            self.block_device.write_block(self.block_id, &self.cache);
+        }
+    }
+}
+
+impl Drop for BlockCache {
+    fn drop(&mut self) {
+        self.sync()
+    }
+}
+
+/// Use a block cache of 16 blocks
+const BLOCK_CACHE_SIZE: usize = 16;
+
+pub struct BlockCacheManager {
+    queue: VecDeque<(usize, Arc<Mutex<BlockCache>>)>,
+}
+
+impl BlockCacheManager {
+    pub fn new() -> Self {
+        Self { queue: VecDeque::new() }
+    }
+
+    pub fn get_block_cache(
+        &mut self,
+        block_id: usize,
+        block_device: Arc<dyn BlockDevice>,
+    ) -> Arc<Mutex<BlockCache>> {
+        if let Some(pair) = self.queue
+            .iter()
+            .find(|pair| pair.0 == block_id) {
+                Arc::clone(&pair.1)
+        } else {
+            // substitute
+            if self.queue.len() == BLOCK_CACHE_SIZE {
+                // from front to tail
+                if let Some((idx, _)) = self.queue
+                    .iter()
+                    .enumerate()
+                    .find(|(_, pair)| Arc::strong_count(&pair.1) == 1) {
+                    self.queue.drain(idx..=idx);
+                } else {
+                    panic!("Run out of BlockCache!");
+                }
+            }
+            // load block into mem and push back
+            let block_cache = Arc::new(Mutex::new(
+                BlockCache::new(block_id, Arc::clone(&block_device))
+            ));
+            self.queue.push_back((block_id, Arc::clone(&block_cache)));
+            block_cache
+        }
+    }
+}
+
+lazy_static! {
+    /// The global block cache manager
+    pub static ref BLOCK_CACHE_MANAGER: Mutex<BlockCacheManager> = Mutex::new(
+        BlockCacheManager::new()
+    );
+}
+
+/// Get the block cache corresponding to the given block id and block device
+pub fn get_block_cache(
+    block_id: usize,
+    block_device: Arc<dyn BlockDevice>
+) -> Arc<Mutex<BlockCache>> {
+    BLOCK_CACHE_MANAGER.lock().get_block_cache(block_id, block_device)
+}
+
+/// Sync all block cache to block device
+pub fn block_cache_sync_all() {
+    let manager = BLOCK_CACHE_MANAGER.lock();
+    for (_, cache) in manager.queue.iter() {
+        cache.lock().sync();
+    }
+}

easy-fs/src/block_dev.rs

@@ -0,0 +1,8 @@
+use core::any::Any;
+
+/// Trait for block devices
+/// which reads and writes data in the unit of blocks
+pub trait BlockDevice : Send + Sync + Any {
+    fn read_block(&self, block_id: usize, buf: &mut [u8]);
+    fn write_block(&self, block_id: usize, buf: &[u8]);
+}

easy-fs/src/efs.rs

@@ -0,0 +1,164 @@
+use alloc::sync::Arc;
+use spin::Mutex;
+use super::{
+    BlockDevice,
+    Bitmap,
+    SuperBlock,
+    DiskInode,
+    DiskInodeType,
+    Inode,
+    get_block_cache,
+    block_cache_sync_all,
+};
+use crate::BLOCK_SZ;
+
+/// An easy fs over a block device
+pub struct EasyFileSystem {
+    pub block_device: Arc<dyn BlockDevice>,
+    pub inode_bitmap: Bitmap,
+    pub data_bitmap: Bitmap,
+    inode_area_start_block: u32,
+    data_area_start_block: u32,
+}
+
+/// A data block of block size
+type DataBlock = [u8; BLOCK_SZ];
+
+impl EasyFileSystem {
+    /// Create a filesystem from a block device
+    pub fn create(
+        block_device: Arc<dyn BlockDevice>,
+        total_blocks: u32,
+        inode_bitmap_blocks: u32,
+    ) -> Arc<Mutex<Self>> {
+        // calculate block size of areas & create bitmaps
+        let inode_bitmap = Bitmap::new(1, inode_bitmap_blocks as usize);
+        let inode_num = inode_bitmap.maximum();
+        let inode_area_blocks =
+            ((inode_num * core::mem::size_of::<DiskInode>() + BLOCK_SZ - 1) / BLOCK_SZ) as u32;
+        let inode_total_blocks = inode_bitmap_blocks + inode_area_blocks;
+        let data_total_blocks = total_blocks - 1 - inode_total_blocks;
+        let data_bitmap_blocks = (data_total_blocks + 4096) / 4097;
+        let data_area_blocks = data_total_blocks - data_bitmap_blocks;
+        let data_bitmap = Bitmap::new(
+            (1 + inode_bitmap_blocks + inode_area_blocks) as usize,
+            data_bitmap_blocks as usize,
+        );
+        let mut efs = Self {
+            block_device: Arc::clone(&block_device),
+            inode_bitmap,
+            data_bitmap,
+            inode_area_start_block: 1 + inode_bitmap_blocks,
+            data_area_start_block: 1 + inode_total_blocks + data_bitmap_blocks,
+        };
+        // clear all blocks
+        for i in 0..total_blocks {
+            get_block_cache(
+                i as usize,
+                Arc::clone(&block_device)
+            )
+            .lock()
+            .modify(0, |data_block: &mut DataBlock| {
+                for byte in data_block.iter_mut() { *byte = 0; }
+            });
+        }
+        // initialize SuperBlock
+        get_block_cache(0, Arc::clone(&block_device))
+        .lock()
+        .modify(0, |super_block: &mut SuperBlock| {
+            super_block.initialize(
+                total_blocks,
+                inode_bitmap_blocks,
+                inode_area_blocks,
+                data_bitmap_blocks,
+                data_area_blocks,
+            );
+        });
+        // write back immediately
+        // create a inode for root node "/"
+        assert_eq!(efs.alloc_inode(), 0);
+        let (root_inode_block_id, root_inode_offset) = efs.get_disk_inode_pos(0);
+        get_block_cache(
+            root_inode_block_id as usize,
+            Arc::clone(&block_device)
+        )
+        .lock()
+        .modify(root_inode_offset, |disk_inode: &mut DiskInode| {
+            disk_inode.initialize(DiskInodeType::Directory);
+        });
+        block_cache_sync_all();
+        Arc::new(Mutex::new(efs))
+    }
+    /// Open a block device as a filesystem
+    pub fn open(block_device: Arc<dyn BlockDevice>) -> Arc<Mutex<Self>> {
+        // read SuperBlock
+        get_block_cache(0, Arc::clone(&block_device))
+            .lock()
+            .read(0, |super_block: &SuperBlock| {
+                assert!(super_block.is_valid(), "Error loading EFS!");
+                let inode_total_blocks =
+                    super_block.inode_bitmap_blocks + super_block.inode_area_blocks;
+                let efs = Self {
+                    block_device,
+                    inode_bitmap: Bitmap::new(
+                        1,
+                        super_block.inode_bitmap_blocks as usize
+                    ),
+                    data_bitmap: Bitmap::new(
+                        (1 + inode_total_blocks) as usize,
+                        super_block.data_bitmap_blocks as usize,
+                    ),
+                    inode_area_start_block: 1 + super_block.inode_bitmap_blocks,
+                    data_area_start_block: 1 + inode_total_blocks + super_block.data_bitmap_blocks,
+                };
+                Arc::new(Mutex::new(efs))
+            })
+    }
+    /// Get the root inode of the filesystem
+    pub fn root_inode(efs: &Arc<Mutex<Self>>) -> Inode {
+        let block_device = Arc::clone(&efs.lock().block_device);
+        // acquire efs lock temporarily
+        let (block_id, block_offset) = efs.lock().get_disk_inode_pos(0);
+        // release efs lock
+        Inode::new(
+            block_id,
+            block_offset,
+            Arc::clone(efs),
+            block_device,
+        )
+    }
+    /// Get inode by id
+    pub fn get_disk_inode_pos(&self, inode_id: u32) -> (u32, usize) {
+        let inode_size = core::mem::size_of::<DiskInode>();
+        let inodes_per_block = (BLOCK_SZ / inode_size) as u32;
+        let block_id = self.inode_area_start_block + inode_id / inodes_per_block;
+        (block_id, (inode_id % inodes_per_block) as usize * inode_size)
+    }
+    /// Get data block by id
+    pub fn get_data_block_id(&self, data_block_id: u32) -> u32 {
+        self.data_area_start_block + data_block_id
+    }
+    /// Allocate a new inode
+    pub fn alloc_inode(&mut self) -> u32 {
+        self.inode_bitmap.alloc(&self.block_device).unwrap() as u32
+    }
+    /// Allocate a data block
+    pub fn alloc_data(&mut self) -> u32 {
+        self.data_bitmap.alloc(&self.block_device).unwrap() as u32 + self.data_area_start_block
+    }
+    /// Deallocate a data block
+    pub fn dealloc_data(&mut self, block_id: u32) {
+        get_block_cache(
+            block_id as usize,
+            Arc::clone(&self.block_device)
+        )
+        .lock()
+        .modify(0, |data_block: &mut DataBlock| {
+            data_block.iter_mut().for_each(|p| { *p = 0; })
+        });
+        self.data_bitmap.dealloc(
+            &self.block_device,
+            (block_id - self.data_area_start_block) as usize
+        )
+    }
+}

easy-fs/src/layout.rs

@@ -0,0 +1,477 @@
+use core::fmt::{Debug, Formatter, Result};
+use super::{
+    BLOCK_SZ,
+    BlockDevice,
+    get_block_cache,
+};
+use alloc::sync::Arc;
+use alloc::vec::Vec;
+
+/// Magic number for sanity check
+const EFS_MAGIC: u32 = 0x3b800001;
+/// The max number of direct inodes
+const INODE_DIRECT_COUNT: usize = 28;
+/// The max length of inode name
+const NAME_LENGTH_LIMIT: usize = 27;
+/// The max number of indirect1 inodes
+const INODE_INDIRECT1_COUNT: usize = BLOCK_SZ / 4;
+/// The max number of indirect2 inodes
+const INODE_INDIRECT2_COUNT: usize = INODE_INDIRECT1_COUNT * INODE_INDIRECT1_COUNT;
+/// The upper bound of direct inode index
+const DIRECT_BOUND: usize = INODE_DIRECT_COUNT;
+/// The upper bound of indirect1 inode index
+const INDIRECT1_BOUND: usize = DIRECT_BOUND + INODE_INDIRECT1_COUNT;
+/// The upper bound of indirect2 inode index
+#[allow(unused)]
+const INDIRECT2_BOUND: usize = INDIRECT1_BOUND + INODE_INDIRECT2_COUNT;
+
+/// Super block of a filesystem
+#[repr(C)]
+pub struct SuperBlock {
+    magic: u32,
+    pub total_blocks: u32,
+    pub inode_bitmap_blocks: u32,
+    pub inode_area_blocks: u32,
+    pub data_bitmap_blocks: u32,
+    pub data_area_blocks: u32,
+}
+
+impl Debug for SuperBlock {
+    fn fmt(&self, f: &mut Formatter<'_>) -> Result {
+        f.debug_struct("SuperBlock")
+            .field("total_blocks", &self.total_blocks)
+            .field("inode_bitmap_blocks", &self.inode_bitmap_blocks)
+            .field("inode_area_blocks", &self.inode_area_blocks)
+            .field("data_bitmap_blocks", &self.data_bitmap_blocks)
+            .field("data_area_blocks", &self.data_area_blocks)
+            .finish()
+    }
+}
+
+impl SuperBlock {
+    /// Initialize a super block
+    pub fn initialize(
+        &mut self,
+        total_blocks: u32,
+        inode_bitmap_blocks: u32,
+        inode_area_blocks: u32,
+        data_bitmap_blocks: u32,
+        data_area_blocks: u32,
+    ) {
+        *self = Self {
+            magic: EFS_MAGIC,
+            total_blocks,
+            inode_bitmap_blocks,
+            inode_area_blocks,
+            data_bitmap_blocks,
+            data_area_blocks,
+        }
+    }
+    /// Check if a super block is valid using efs magic
+    pub fn is_valid(&self) -> bool {
+        self.magic == EFS_MAGIC
+    }
+}
+
+/// Type of a disk inode
+#[derive(PartialEq)]
+pub enum DiskInodeType {
+    File,
+    Directory,
+}
+
+/// A indirect block
+type IndirectBlock = [u32; BLOCK_SZ / 4];
+/// A data block
+type DataBlock = [u8; BLOCK_SZ];
+
+/// A disk inode
+#[repr(C)]
+pub struct DiskInode {
+    pub size: u32,
+    pub direct: [u32; INODE_DIRECT_COUNT],
+    pub indirect1: u32,
+    pub indirect2: u32,
+    type_: DiskInodeType,
+}
+
+impl DiskInode {
+    /// Initialize a disk inode, as well as all direct inodes under it
+    /// indirect1 and indirect2 block are allocated only when they are needed
+    pub fn initialize(&mut self, type_: DiskInodeType) {
+        self.size = 0;
+        self.direct.iter_mut().for_each(|v| *v = 0);
+        self.indirect1 = 0;
+        self.indirect2 = 0;
+        self.type_ = type_;
+    }
+    /// Whether this inode is a directory
+    pub fn is_dir(&self) -> bool {
+        self.type_ == DiskInodeType::Directory
+    }
+    /// Whether this inode is a file
+    #[allow(unused)]
+    pub fn is_file(&self) -> bool {
+        self.type_ == DiskInodeType::File
+    }
+    /// Get the number of data blocks corresponding to size
+    pub fn data_blocks(&self) -> u32 {
+        Self::_data_blocks(self.size)
+    }
+    fn _data_blocks(size: u32) -> u32 {
+        (size + BLOCK_SZ as u32 - 1) / BLOCK_SZ as u32
+    }
+    /// Get the number of data blocks required for the given size of data
+    pub fn total_blocks(size: u32) -> u32 {
+        let data_blocks = Self::_data_blocks(size) as usize;
+        let mut total = data_blocks as usize;
+        // indirect1
+        if data_blocks > INODE_DIRECT_COUNT {
+            total += 1;
+        }
+        // indirect2
+        if data_blocks > INDIRECT1_BOUND {
+            total += 1;
+            // sub indirect1
+            total += (data_blocks - INDIRECT1_BOUND + INODE_INDIRECT1_COUNT - 1) / INODE_INDIRECT1_COUNT;
+        }
+        total as u32
+    }
+    /// Get the number of data blocks that have to be allocated given the new size of data
+    pub fn blocks_num_needed(&self, new_size: u32) -> u32 {
+        assert!(new_size >= self.size);
+        Self::total_blocks(new_size) - Self::total_blocks(self.size)
+    }
+    /// Get id of block given inner id
+    pub fn get_block_id(&self, inner_id: u32, block_device: &Arc<dyn BlockDevice>) -> u32 {
+        let inner_id = inner_id as usize;
+        if inner_id < INODE_DIRECT_COUNT {
+            self.direct[inner_id]
+        } else if inner_id < INDIRECT1_BOUND {
+            get_block_cache(self.indirect1 as usize, Arc::clone(block_device))
+                .lock()
+                .read(0, |indirect_block: &IndirectBlock| {
+                    indirect_block[inner_id - INODE_DIRECT_COUNT]
+                })
+        } else {
+            let last = inner_id - INDIRECT1_BOUND;
+            let indirect1 = get_block_cache(
+                self.indirect2 as usize,
+                Arc::clone(block_device)
+            )
+            .lock()
+            .read(0, |indirect2: &IndirectBlock| {
+                indirect2[last / INODE_INDIRECT1_COUNT]
+            });
+            get_block_cache(
+                indirect1 as usize,
+                Arc::clone(block_device)
+            )
+            .lock()
+            .read(0, |indirect1: &IndirectBlock| {
+                indirect1[last % INODE_INDIRECT1_COUNT]
+            })
+        }
+    }
+    /// Inncrease the size of current disk inode
+    pub fn increase_size(
+        &mut self,
+        new_size: u32,
+        new_blocks: Vec<u32>,
+        block_device: &Arc<dyn BlockDevice>,
+    ) {
+        let mut current_blocks = self.data_blocks();
+        self.size = new_size;
+        let mut total_blocks = self.data_blocks();
+        let mut new_blocks = new_blocks.into_iter();
+        // fill direct
+        while current_blocks < total_blocks.min(INODE_DIRECT_COUNT as u32) {
+            self.direct[current_blocks as usize] = new_blocks.next().unwrap();
+            current_blocks += 1;
+        }
+        // alloc indirect1
+        if total_blocks > INODE_DIRECT_COUNT as u32{
+            if current_blocks == INODE_DIRECT_COUNT as u32 {
+                self.indirect1 = new_blocks.next().unwrap();
+            }
+            current_blocks -= INODE_DIRECT_COUNT as u32;
+            total_blocks -= INODE_DIRECT_COUNT as u32;
+        } else {
+            return;
+        }
+        // fill indirect1
+        get_block_cache(
+            self.indirect1 as usize,
+            Arc::clone(block_device)
+        )
+        .lock()
+        .modify(0, |indirect1: &mut IndirectBlock| {
+            while current_blocks < total_blocks.min(INODE_INDIRECT1_COUNT as u32) {
+                indirect1[current_blocks as usize] = new_blocks.next().unwrap();
+                current_blocks += 1;
+            }
+        });
+        // alloc indirect2
+        if total_blocks > INODE_INDIRECT1_COUNT as u32 {
+            if current_blocks == INODE_INDIRECT1_COUNT as u32 {
+                self.indirect2 = new_blocks.next().unwrap();
+            }
+            current_blocks -= INODE_INDIRECT1_COUNT as u32;
+            total_blocks -= INODE_INDIRECT1_COUNT as u32;
+        } else {
+            return;
+        }
+        // fill indirect2 from (a0, b0) -> (a1, b1)
+        let mut a0 = current_blocks as usize / INODE_INDIRECT1_COUNT;
+        let mut b0 = current_blocks as usize % INODE_INDIRECT1_COUNT;
+        let a1 = total_blocks as usize / INODE_INDIRECT1_COUNT;
+        let b1 = total_blocks as usize % INODE_INDIRECT1_COUNT;
+        // alloc low-level indirect1
+        get_block_cache(
+            self.indirect2 as usize,
+            Arc::clone(block_device)
+        )
+        .lock()
+        .modify(0, |indirect2: &mut IndirectBlock| {
+            while (a0 < a1) || (a0 == a1 && b0 < b1) {
+                if b0 == 0 {
+                    indirect2[a0] = new_blocks.next().unwrap();
+                }
+                // fill current
+                get_block_cache(
+                    indirect2[a0] as usize,
+                    Arc::clone(block_device)
+                )
+                .lock()
+                .modify(0, |indirect1: &mut IndirectBlock| {
+                    indirect1[b0] = new_blocks.next().unwrap();
+                });
+                // move to next
+                b0 += 1;
+                if b0 == INODE_INDIRECT1_COUNT {
+                    b0 = 0;
+                    a0 += 1;
+                }
+            }
+        });
+    }
+    /// Clear size to zero and return blocks that should be deallocated
+    /// and clear the block contents to zero later
+    pub fn clear_size(&mut self, block_device: &Arc<dyn BlockDevice>) -> Vec<u32> {
+        let mut v: Vec<u32> = Vec::new();
+        let mut data_blocks = self.data_blocks() as usize;
+        self.size = 0;
+        let mut current_blocks = 0usize;
+        // direct
+        while current_blocks < data_blocks.min(INODE_DIRECT_COUNT) {
+            v.push(self.direct[current_blocks]);
+            self.direct[current_blocks] = 0;
+            current_blocks += 1;
+        }
+        // indirect1 block
+        if data_blocks > INODE_DIRECT_COUNT {
+            v.push(self.indirect1);
+            data_blocks -= INODE_DIRECT_COUNT;
+            current_blocks = 0;
+        } else {
+            return v;
+        }
+        // indirect1
+        get_block_cache(
+            self.indirect1 as usize,
+            Arc::clone(block_device),
+        )
+        .lock()
+        .modify(0, |indirect1: &mut IndirectBlock| {
+            while current_blocks < data_blocks.min(INODE_INDIRECT1_COUNT) {
+                v.push(indirect1[current_blocks]);
+                //indirect1[current_blocks] = 0;
+                current_blocks += 1;
+            }
+        });
+        self.indirect1 = 0;
+        // indirect2 block
+        if data_blocks > INODE_INDIRECT1_COUNT {
+            v.push(self.indirect2);
+            data_blocks -= INODE_INDIRECT1_COUNT;
+        } else {
+            return v;
+        }
+        // indirect2
+        assert!(data_blocks <= INODE_INDIRECT2_COUNT);
+        let a1 = data_blocks / INODE_INDIRECT1_COUNT;
+        let b1 = data_blocks % INODE_INDIRECT1_COUNT;
+        get_block_cache(
+            self.indirect2 as usize,
+            Arc::clone(block_device),
+        )
+        .lock()
+        .modify(0, |indirect2: &mut IndirectBlock| {
+            // full indirect1 blocks
+            for i in 0..a1 {
+                v.push(indirect2[i]);
+                get_block_cache(
+                    indirect2[i] as usize,
+                    Arc::clone(block_device),
+                )
+                .lock()
+                .modify(0, |indirect1: &mut IndirectBlock| {
+                    for j in 0..INODE_INDIRECT1_COUNT {
+                        v.push(indirect1[j]);
+                        //indirect1[j] = 0;
+                    }
+                });
+                //indirect2[i] = 0;
+            }
+            // last indirect1 block
+            if b1 > 0 {
+                v.push(indirect2[a1]);
+                get_block_cache(
+                    indirect2[a1] as usize,
+                    Arc::clone(block_device),
+                )
+                .lock()
+                .modify(0, |indirect1: &mut IndirectBlock| {
+                    for j in 0..b1 {
+                        v.push(indirect1[j]);
+                        //indirect1[j] = 0;
+                    }
+                });
+                //indirect2[a1] = 0;
+            }
+        });
+        self.indirect2 = 0;
+        v
+    }
+    /// Read data from current disk inode
+    pub fn read_at(
+        &self,
+        offset: usize,
+        buf: &mut [u8],
+        block_device: &Arc<dyn BlockDevice>,
+    ) -> usize {
+        let mut start = offset;
+        let end = (offset + buf.len()).min(self.size as usize);
+        if start >= end {
+            return 0;
+        }
+        let mut start_block = start / BLOCK_SZ;
+        let mut read_size = 0usize;
+        loop {
+            // calculate end of current block
+            let mut end_current_block = (start / BLOCK_SZ + 1) * BLOCK_SZ;
+            end_current_block = end_current_block.min(end);
+            // read and update read size
+            let block_read_size = end_current_block - start;
+            let dst = &mut buf[read_size..read_size + block_read_size];
+            get_block_cache(
+                self.get_block_id(start_block as u32, block_device) as usize,
+                Arc::clone(block_device),
+            )
+            .lock()
+            .read(0, |data_block: &DataBlock| {
+                let src = &data_block[start % BLOCK_SZ..start % BLOCK_SZ + block_read_size];
+                dst.copy_from_slice(src);
+            });
+            read_size += block_read_size;
+            // move to next block
+            if end_current_block == end { break; }
+            start_block += 1;
+            start = end_current_block;
+        }
+        read_size
+    }
+    /// Write data into current disk inode
+    /// size must be adjusted properly beforehand
+    pub fn write_at(
+        &mut self,
+        offset: usize,
+        buf: &[u8],
+        block_device: &Arc<dyn BlockDevice>,
+    ) -> usize {
+        let mut start = offset;
+        let end = (offset + buf.len()).min(self.size as usize);
+        assert!(start <= end);
+        let mut start_block = start / BLOCK_SZ;
+        let mut write_size = 0usize;
+        loop {
+            // calculate end of current block
+            let mut end_current_block = (start / BLOCK_SZ + 1) * BLOCK_SZ;
+            end_current_block = end_current_block.min(end);
+            // write and update write size
+            let block_write_size = end_current_block - start;
+            get_block_cache(
+                self.get_block_id(start_block as u32, block_device) as usize,
+                Arc::clone(block_device)
+            )
+            .lock()
+            .modify(0, |data_block: &mut DataBlock| {
+                let src = &buf[write_size..write_size + block_write_size];
+                let dst = &mut data_block[start % BLOCK_SZ..start % BLOCK_SZ + block_write_size];
+                dst.copy_from_slice(src);
+            });
+            write_size += block_write_size;
+            // move to next block
+            if end_current_block == end { break; }
+            start_block += 1;
+            start = end_current_block;
+        }
+        write_size
+    }
+}
+
+/// A directory entry
+#[repr(C)]
+pub struct DirEntry {
+    name: [u8; NAME_LENGTH_LIMIT + 1],
+    inode_number: u32,
+}
+
+/// Size of a directory entry
+pub const DIRENT_SZ: usize = 32;
+
+impl DirEntry {
+    /// Create an empty directory entry
+    pub fn empty() -> Self {
+        Self {
+            name: [0u8; NAME_LENGTH_LIMIT + 1],
+            inode_number: 0,
+        }
+    }
+    /// Crate a directory entry from name and inode number
+    pub fn new(name: &str, inode_number: u32) -> Self {
+        let mut bytes = [0u8; NAME_LENGTH_LIMIT + 1];
+        bytes[..name.len()].copy_from_slice(name.as_bytes());
+        Self {
+            name: bytes,
+            inode_number,
+        }
+    }
+    /// Serialize into bytes
+    pub fn as_bytes(&self) -> &[u8] {
+        unsafe {
+            core::slice::from_raw_parts(
+                self as *const _ as usize as *const u8,
+                DIRENT_SZ,
+            )
+        }
+    }
+    /// Serialize into mutable bytes
+    pub fn as_bytes_mut(&mut self) -> &mut [u8] {
+        unsafe {
+            core::slice::from_raw_parts_mut(
+                self as *mut _ as usize as *mut u8,
+                DIRENT_SZ,
+            )
+        }
+    }
+    /// Get name of the entry
+    pub fn name(&self) -> &str {
+        let len = (0usize..).find(|i| self.name[*i] == 0).unwrap();
+        core::str::from_utf8(&self.name[..len]).unwrap()
+    }
+    /// Get inode number of the entry
+    pub fn inode_number(&self) -> u32 {
+        self.inode_number
+    }
+}

easy-fs/src/lib.rs

@@ -0,0 +1,19 @@
+#![no_std]
+
+extern crate alloc;
+
+mod block_dev;
+mod layout;
+mod efs;
+mod bitmap;
+mod vfs;
+mod block_cache;
+
+/// Use a block size of 512 bytes
+pub const BLOCK_SZ: usize = 512;
+pub use block_dev::BlockDevice;
+pub use efs::EasyFileSystem;
+pub use vfs::Inode;
+use layout::*;
+use bitmap::Bitmap;
+use block_cache::{get_block_cache, block_cache_sync_all};

easy-fs/src/vfs.rs

@@ -0,0 +1,211 @@
+use super::{
+    BlockDevice,
+    DiskInode,
+    DiskInodeType,
+    DirEntry,
+    EasyFileSystem,
+    DIRENT_SZ,
+    get_block_cache,
+    block_cache_sync_all,
+};
+use alloc::sync::Arc;
+use alloc::string::String;
+use alloc::vec::Vec;
+use spin::{Mutex, MutexGuard};
+
+/// Virtual filesystem layer over easy-fs
+pub struct Inode {
+    block_id: usize,
+    block_offset: usize,
+    fs: Arc<Mutex<EasyFileSystem>>,
+    block_device: Arc<dyn BlockDevice>,
+}
+
+impl Inode {
+    /// Create a vfs inode
+    pub fn new(
+        block_id: u32,
+        block_offset: usize,
+        fs: Arc<Mutex<EasyFileSystem>>,
+        block_device: Arc<dyn BlockDevice>,
+    ) -> Self {
+        Self {
+            block_id: block_id as usize,
+            block_offset,
+            fs,
+            block_device,
+        }
+    }
+    /// Call a function over a disk inode to read it
+    fn read_disk_inode<V>(&self, f: impl FnOnce(&DiskInode) -> V) -> V {
+        get_block_cache(
+            self.block_id,
+            Arc::clone(&self.block_device)
+        ).lock().read(self.block_offset, f)
+    }
+    /// Call a function over a disk inode to modify it
+    fn modify_disk_inode<V>(&self, f: impl FnOnce(&mut DiskInode) -> V) -> V {
+        get_block_cache(
+            self.block_id,
+            Arc::clone(&self.block_device)
+        ).lock().modify(self.block_offset, f)
+    }
+    /// Find inode under a disk inode by name
+    fn find_inode_id(
+        &self,
+        name: &str,
+        disk_inode: &DiskInode,
+    ) -> Option<u32> {
+        // assert it is a directory
+        assert!(disk_inode.is_dir());
+        let file_count = (disk_inode.size as usize) / DIRENT_SZ;
+        let mut dirent = DirEntry::empty();
+        for i in 0..file_count {
+            assert_eq!(
+                disk_inode.read_at(
+                    DIRENT_SZ * i,
+                    dirent.as_bytes_mut(),
+                    &self.block_device,
+                ),
+                DIRENT_SZ,
+            );
+            if dirent.name() == name {
+                return Some(dirent.inode_number() as u32);
+            }
+        }
+        None
+    }
+    /// Find inode under current inode by name
+    pub fn find(&self, name: &str) -> Option<Arc<Inode>> {
+        let fs = self.fs.lock();
+        self.read_disk_inode(|disk_inode| {
+            self.find_inode_id(name, disk_inode)
+            .map(|inode_id| {
+                let (block_id, block_offset) = fs.get_disk_inode_pos(inode_id);
+                Arc::new(Self::new(
+                    block_id,
+                    block_offset,
+                    self.fs.clone(),
+                    self.block_device.clone(),
+                ))
+            })
+        })
+    }
+    /// Increase the size of a disk inode
+    fn increase_size(
+        &self,
+        new_size: u32,
+        disk_inode: &mut DiskInode,
+        fs: &mut MutexGuard<EasyFileSystem>,
+    ) {
+        if new_size < disk_inode.size {
+            return;
+        }
+        let blocks_needed = disk_inode.blocks_num_needed(new_size);
+        let mut v: Vec<u32> = Vec::new();
+        for _ in 0..blocks_needed {
+            v.push(fs.alloc_data());
+        }
+        disk_inode.increase_size(new_size, v, &self.block_device);
+    }
+    /// Create inode under current inode by name
+    pub fn create(&self, name: &str) -> Option<Arc<Inode>> {
+        let mut fs = self.fs.lock();
+        if self.modify_disk_inode(|root_inode| {
+            // assert it is a directory
+            assert!(root_inode.is_dir());
+            // has the file been created?
+            self.find_inode_id(name, root_inode)
+        }).is_some() {
+            return None;
+        }
+        // create a new file
+        // alloc a inode with an indirect block
+        let new_inode_id = fs.alloc_inode();
+        // initialize inode
+        let (new_inode_block_id, new_inode_block_offset) 
+            = fs.get_disk_inode_pos(new_inode_id);
+        get_block_cache(
+            new_inode_block_id as usize,
+            Arc::clone(&self.block_device)
+        ).lock().modify(new_inode_block_offset, |new_inode: &mut DiskInode| {
+            new_inode.initialize(DiskInodeType::File);
+        });
+        self.modify_disk_inode(|root_inode| {
+            // append file in the dirent
+            let file_count = (root_inode.size as usize) / DIRENT_SZ;
+            let new_size = (file_count + 1) * DIRENT_SZ;
+            // increase size
+            self.increase_size(new_size as u32, root_inode, &mut fs);
+            // write dirent
+            let dirent = DirEntry::new(name, new_inode_id);
+            root_inode.write_at(
+                file_count * DIRENT_SZ,
+                dirent.as_bytes(),
+                &self.block_device,
+            );
+        });
+
+        let (block_id, block_offset) = fs.get_disk_inode_pos(new_inode_id);
+        block_cache_sync_all();
+        // return inode
+        Some(Arc::new(Self::new(
+            block_id,
+            block_offset,
+            self.fs.clone(),
+            self.block_device.clone(),
+        )))
+        // release efs lock automatically by compiler
+    }
+    /// List inodes under current inode
+    pub fn ls(&self) -> Vec<String> {
+        let _fs = self.fs.lock();
+        self.read_disk_inode(|disk_inode| {
+            let file_count = (disk_inode.size as usize) / DIRENT_SZ;
+            let mut v: Vec<String> = Vec::new();
+            for i in 0..file_count {
+                let mut dirent = DirEntry::empty();
+                assert_eq!(
+                    disk_inode.read_at(
+                        i * DIRENT_SZ,
+                        dirent.as_bytes_mut(),
+                        &self.block_device,
+                    ),
+                    DIRENT_SZ,
+                );
+                v.push(String::from(dirent.name()));
+            }
+            v
+        })
+    }
+    /// Read data from current inode
+    pub fn read_at(&self, offset: usize, buf: &mut [u8]) -> usize {
+        let _fs = self.fs.lock();
+        self.read_disk_inode(|disk_inode| {
+            disk_inode.read_at(offset, buf, &self.block_device)
+        })
+    }
+    /// Write data to current inode
+    pub fn write_at(&self, offset: usize, buf: &[u8]) -> usize {
+        let mut fs = self.fs.lock();
+        let size = self.modify_disk_inode(|disk_inode| {
+            self.increase_size((offset + buf.len()) as u32, disk_inode, &mut fs);
+            disk_inode.write_at(offset, buf, &self.block_device)
+        });
+        block_cache_sync_all();
+        size
+    }
+    /// Clear the data in current inode
+    pub fn clear(&self) {
+        let mut fs = self.fs.lock();
+        self.modify_disk_inode(|disk_inode| {
+            let size = disk_inode.size;
+            let data_blocks_dealloc = disk_inode.clear_size(&self.block_device);
+            assert!(data_blocks_dealloc.len() == DiskInode::total_blocks(size) as usize);
+            for data_block in data_blocks_dealloc.into_iter() {
+                fs.dealloc_data(data_block);
+            }
+        });
+        block_cache_sync_all();
+    }
+}

os1/.cargo/config

@@ -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"
+]

os1/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "os"
+version = "0.1.0"
+authors = ["Yifan Wu <shinbokuow@163.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+log = "0.4"

os1/Makefile

@@ -0,0 +1,49 @@
+# Building
+TARGET := riscv64gc-unknown-none-elf
+MODE := release
+KERNEL_ELF := target/$(TARGET)/$(MODE)/os
+KERNEL_BIN := $(KERNEL_ELF).bin
+
+# BOARD
+BOARD ?= qemu
+SBI ?= rustsbi
+BOOTLOADER := ../bootloader/$(SBI)-$(BOARD).bin
+
+# KERNEL ENTRY
+KERNEL_ENTRY_PA := 0x80200000
+
+# Binutils
+OBJDUMP := rust-objdump --arch-name=riscv64
+OBJCOPY := rust-objcopy --binary-architecture=riscv64
+
+build: env $(KERNEL_BIN)
+
+$(KERNEL_BIN): kernel
+	@$(OBJCOPY) $(KERNEL_ELF) --strip-all -O binary $@
+
+env:
+	(rustup target list | grep "riscv64gc-unknown-none-elf (installed)") || rustup target add $(TARGET)
+	cargo install cargo-binutils --vers ~0.2
+	rustup component add rust-src
+	rustup component add llvm-tools-preview
+
+kernel:
+	@cargo build --release
+
+clean:
+	@cargo clean
+
+run: build
+	@qemu-system-riscv64 \
+		-machine virt \
+		-nographic \
+		-bios $(BOOTLOADER) \
+		-device loader,file=$(KERNEL_BIN),addr=$(KERNEL_ENTRY_PA)
+
+debug: build
+	@tmux new-session -d \
+		"qemu-system-riscv64 -machine virt -nographic -bios $(BOOTLOADER) -device loader,file=$(KERNEL_BIN),addr=$(KERNEL_ENTRY_PA) -s -S" && \
+		tmux split-window -h "riscv64-unknown-elf-gdb -ex 'file $(KERNEL_ELF)' -ex 'set arch riscv:rv64' -ex 'target remote localhost:1234'" && \
+		tmux -2 attach-session -d
+
+.PHONY: build env kernel clean run-inner

os1/src/console.rs

@@ -0,0 +1,37 @@
+/*！
+
+本模块实现了 print 和 println 宏。
+
+*/
+
+use crate::sbi::console_putchar;
+use core::fmt::{self, Write};
+
+struct Stdout;
+
+impl Write for Stdout {
+    fn write_str(&mut self, s: &str) -> fmt::Result {
+        for c in s.chars() {
+            console_putchar(c as usize);
+        }
+        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)+)?));
+    }
+}

os1/src/entry.asm

@@ -0,0 +1,12 @@
+    .section .text.entry
+    .globl _start
+_start:
+    la sp, boot_stack_top
+    call rust_main
+
+    .section .bss.stack
+    .globl boot_stack
+boot_stack:
+    .space 4096 * 16
+    .globl boot_stack_top
+boot_stack_top:

os1/src/lang_items.rs

@@ -0,0 +1,17 @@
+use crate::sbi::shutdown;
+use core::panic::PanicInfo;
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    if let Some(location) = info.location() {
+        println!(
+            "Panicked at {}:{} {}",
+            location.file(),
+            location.line(),
+            info.message().unwrap()
+        );
+    } else {
+        println!("Panicked: {}", info.message().unwrap());
+    }
+    shutdown()
+}

os1/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 : {
+        *(.rodata .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)
+    }
+}

os1/src/logging.rs

@@ -0,0 +1,47 @@
+/*！
+
+本模块利用 log crate 为你提供了日志功能，使用方式见 main.rs.
+
+*/
+
+use log::{self, Level, LevelFilter, Log, Metadata, Record};
+
+struct SimpleLogger;
+
+impl Log for SimpleLogger {
+    fn enabled(&self, _metadata: &Metadata) -> bool {
+        true
+    }
+    fn log(&self, record: &Record) {
+        if !self.enabled(record.metadata()) {
+            return;
+        }
+        let color = match record.level() {
+            Level::Error => 31, // Red
+            Level::Warn => 93,  // BrightYellow
+            Level::Info => 34,  // Blue
+            Level::Debug => 32, // Green
+            Level::Trace => 90, // BrightBlack
+        };
+        println!(
+            "\u{1B}[{}m[{:>5}] {}\u{1B}[0m",
+            color,
+            record.level(),
+            record.args(),
+        );
+    }
+    fn flush(&self) {}
+}
+
+pub fn init() {
+    static LOGGER: SimpleLogger = SimpleLogger;
+    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,
+    });
+}

os1/src/main.rs

@@ -0,0 +1,49 @@
+#![no_std]
+#![no_main]
+#![feature(panic_info_message)]
+
+use log::*;
+
+#[macro_use]
+mod console;
+mod lang_items;
+mod logging;
+mod sbi;
+
+core::arch::global_asm!(include_str!("entry.asm"));
+
+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) });
+}
+
+#[no_mangle]
+pub fn rust_main() -> ! {
+    extern "C" {
+        fn stext();
+        fn etext();
+        fn srodata();
+        fn erodata();
+        fn sdata();
+        fn edata();
+        fn sbss();
+        fn ebss();
+        fn boot_stack();
+        fn boot_stack_top();
+    }
+    clear_bss();
+    logging::init();
+    println!("Hello, world!");
+    trace!(".text [{:#x}, {:#x})", stext as usize, etext as usize);
+    debug!(".rodata [{:#x}, {:#x})", srodata as usize, erodata as usize);
+    info!(".data [{:#x}, {:#x})", sdata as usize, edata as usize);
+    warn!(
+        "boot_stack [{:#x}, {:#x})",
+        boot_stack as usize, boot_stack_top as usize
+    );
+    error!(".bss [{:#x}, {:#x})", sbss as usize, ebss as usize);
+    panic!("Shutdown machine!");
+}

os1/src/sbi.rs

@@ -0,0 +1,34 @@
+#![allow(unused)]
+
+const SBI_SET_TIMER: usize = 0;
+const SBI_CONSOLE_PUTCHAR: usize = 1;
+const SBI_CONSOLE_GETCHAR: usize = 2;
+const SBI_SHUTDOWN: usize = 8;
+
+#[inline(always)]
+fn sbi_call(which: usize, arg0: usize, arg1: usize, arg2: usize) -> usize {
+    let mut ret;
+    unsafe {
+        core::arch::asm!(
+            "ecall",
+            inlateout("x10") arg0 => ret,
+            in("x11") arg1,
+            in("x12") arg2,
+            in("x17") which,
+        );
+    }
+    ret
+}
+
+pub fn console_putchar(c: usize) {
+    sbi_call(SBI_CONSOLE_PUTCHAR, c, 0, 0);
+}
+
+pub fn console_getchar() -> usize {
+    sbi_call(SBI_CONSOLE_GETCHAR, 0, 0, 0)
+}
+
+pub fn shutdown() -> ! {
+    sbi_call(SBI_SHUTDOWN, 0, 0, 0);
+    panic!("It should shutdown!");
+}

os2/.cargo/config

@@ -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"
+]

os2/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "os"
+version = "0.1.0"
+authors = ["Yifan Wu <shinbokuow@163.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+lazy_static = { version = "1.4.0", features = ["spin_no_std"] }
+log = "0.4"
+riscv = { git = "https://gitee.com/rcore-os/riscv", features = ["inline-asm"] }

os2/Makefile

@@ -0,0 +1,58 @@
+# Building
+TARGET := riscv64gc-unknown-none-elf
+MODE := release
+KERNEL_ELF := target/$(TARGET)/$(MODE)/os
+KERNEL_BIN := $(KERNEL_ELF).bin
+KERNEL_ASM := $(KERNEL_ELF).asm
+
+# BOARD
+BOARD ?= qemu
+SBI ?= rustsbi
+BOOTLOADER := ../bootloader/$(SBI)-$(BOARD).bin
+
+# KERNEL ENTRY
+KERNEL_ENTRY_PA := 0x80200000
+
+# Binutils
+OBJDUMP := rust-objdump --arch-name=riscv64
+OBJCOPY := rust-objcopy --binary-architecture=riscv64
+
+CHAPTER ?= 2
+TEST ?= $(CHAPTER)
+BASE ?= 1
+
+build: env $(KERNEL_BIN)
+
+$(KERNEL_BIN): kernel
+	@$(OBJCOPY) $(KERNEL_ELF) --strip-all -O binary $@
+
+disasm:
+	@$(OBJDUMP) $(KERNEL_ELF) -S > $(KERNEL_ELF).asm
+
+env:
+	(rustup target list | grep "riscv64gc-unknown-none-elf (installed)") || rustup target add $(TARGET)
+	cargo install cargo-binutils --vers ~0.2
+	rustup component add rust-src
+	rustup component add llvm-tools-preview
+
+kernel:
+	@make -C ../user build TEST=$(TEST) CHAPTER=$(CHAPTER) BASE=$(BASE)
+	@cargo build --release
+
+clean:
+	@cargo clean
+
+run: build
+	@qemu-system-riscv64 \
+		-machine virt \
+		-nographic \
+		-bios $(BOOTLOADER) \
+		-device loader,file=$(KERNEL_BIN),addr=$(KERNEL_ENTRY_PA)
+
+debug: build
+	@tmux new-session -d \
+		"qemu-system-riscv64 -machine virt -nographic -bios $(BOOTLOADER) -device loader,file=$(KERNEL_BIN),addr=$(KERNEL_ENTRY_PA) -s -S" && \
+		tmux split-window -h "riscv64-unknown-elf-gdb -ex 'file $(KERNEL_ELF)' -ex 'set arch riscv:rv64' -ex 'target remote localhost:1234'" && \
+		tmux -2 attach-session -d
+
+.PHONY: build env kernel clean run-inner

os2/build.rs

@@ -0,0 +1,56 @@
+use std::fs::{read_dir, File};
+use std::io::{Result, Write};
+
+fn main() {
+    println!("cargo:rerun-if-changed=../user/src/");
+    println!("cargo:rerun-if-changed={}", TARGET_PATH);
+    insert_app_data().unwrap();
+}
+
+static TARGET_PATH: &str = "../user/build/bin/";
+
+fn insert_app_data() -> Result<()> {
+    let mut f = File::create("src/link_app.S").unwrap();
+    let mut apps: Vec<_> = read_dir("../user/build/bin/")
+        .unwrap()
+        .into_iter()
+        .map(|dir_entry| {
+            let mut name_with_ext = dir_entry.unwrap().file_name().into_string().unwrap();
+            name_with_ext.drain(name_with_ext.find('.').unwrap()..name_with_ext.len());
+            name_with_ext
+        })
+        .collect();
+    apps.sort();
+
+    writeln!(
+        f,
+        r#"
+    .align 3
+    .section .data
+    .global _num_app
+_num_app:
+    .quad {}"#,
+        apps.len()
+    )?;
+
+    for i in 0..apps.len() {
+        writeln!(f, r#"    .quad app_{}_start"#, i)?;
+    }
+    writeln!(f, r#"    .quad app_{}_end"#, apps.len() - 1)?;
+
+    for (idx, app) in apps.iter().enumerate() {
+        println!("app_{}: {}", idx, app);
+        writeln!(
+            f,
+            r#"
+    .section .data
+    .global app_{0}_start
+    .global app_{0}_end
+app_{0}_start:
+    .incbin "{2}{1}.bin"
+app_{0}_end:"#,
+            idx, app, TARGET_PATH
+        )?;
+    }
+    Ok(())
+}

os2/src/batch.rs

@@ -0,0 +1,141 @@
+use crate::sync::UPSafeCell;
+use crate::trap::TrapContext;
+use lazy_static::*;
+
+const USER_STACK_SIZE: usize = 4096;
+const KERNEL_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() - core::mem::size_of::<TrapContext>()) 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!("[kernel] num_app = {}", self.num_app);
+        for i in 0..self.num_app {
+            info!(
+                "[kernel] app_{} [{:#x}, {:#x})",
+                i,
+                self.app_start[i],
+                self.app_start[i + 1]
+            );
+        }
+    }
+
+    unsafe fn load_app(&self, app_id: usize) {
+        if app_id >= self.num_app {
+            panic!("All applications completed!");
+        }
+        info!("[kernel] Loading app_{}", app_id);
+        // clear icache
+        core::arch::asm!("fence.i");
+        // clear app area
+        core::slice::from_raw_parts_mut(APP_BASE_ADDRESS as *mut u8, APP_SIZE_LIMIT).fill(0);
+        let app_src = core::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 = core::slice::from_raw_parts_mut(APP_BASE_ADDRESS as *mut u8, app_src.len());
+        app_dst.copy_from_slice(app_src);
+    }
+
+    pub fn get_current_app(&self) -> usize {
+        self.current_app
+    }
+
+    pub fn move_to_next_app(&mut self) {
+        self.current_app += 1;
+    }
+}
+
+lazy_static! {
+    static ref APP_MANAGER: UPSafeCell<AppManager> = 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] =
+                core::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);
+    // before this we have to drop local variables related to resources manually
+    // and release the resources
+    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!");
+}

os2/src/console.rs

@@ -0,0 +1,37 @@
+/*！
+
+本模块实现了 print 和 println 宏。
+
+*/
+
+use crate::sbi::console_putchar;
+use core::fmt::{self, Write};
+
+struct Stdout;
+
+impl Write for Stdout {
+    fn write_str(&mut self, s: &str) -> fmt::Result {
+        for c in s.chars() {
+            console_putchar(c as usize);
+        }
+        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)+)?));
+    }
+}

os2/src/entry.asm

@@ -0,0 +1,12 @@
+    .section .text.entry
+    .globl _start
+_start:
+    la sp, boot_stack_top
+    call rust_main
+
+    .section .bss.stack
+    .globl boot_stack
+boot_stack:
+    .space 4096 * 16
+    .globl boot_stack_top
+boot_stack_top:

os2/src/lang_items.rs

@@ -0,0 +1,17 @@
+use crate::sbi::shutdown;
+use core::panic::PanicInfo;
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    if let Some(location) = info.location() {
+        println!(
+            "Panicked at {}:{} {}",
+            location.file(),
+            location.line(),
+            info.message().unwrap()
+        );
+    } else {
+        println!("Panicked: {}", info.message().unwrap());
+    }
+    shutdown()
+}

os2/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 : {
+        *(.rodata .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)
+    }
+}

os2/src/logging.rs

@@ -0,0 +1,47 @@
+/*！
+
+本模块利用 log crate 为你提供了日志功能，使用方式见 main.rs.
+
+*/
+
+use log::{self, Level, LevelFilter, Log, Metadata, Record};
+
+struct SimpleLogger;
+
+impl Log for SimpleLogger {
+    fn enabled(&self, _metadata: &Metadata) -> bool {
+        true
+    }
+    fn log(&self, record: &Record) {
+        if !self.enabled(record.metadata()) {
+            return;
+        }
+        let color = match record.level() {
+            Level::Error => 31, // Red
+            Level::Warn => 93,  // BrightYellow
+            Level::Info => 34,  // Blue
+            Level::Debug => 32, // Green
+            Level::Trace => 90, // BrightBlack
+        };
+        println!(
+            "\u{1B}[{}m[{:>5}] {}\u{1B}[0m",
+            color,
+            record.level(),
+            record.args(),
+        );
+    }
+    fn flush(&self) {}
+}
+
+pub fn init() {
+    static LOGGER: SimpleLogger = SimpleLogger;
+    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,
+    });
+}

os2/src/main.rs

@@ -0,0 +1,40 @@
+#![no_std]
+#![no_main]
+#![feature(panic_info_message)]
+
+#[macro_use]
+extern crate log;
+
+#[macro_use]
+mod console;
+mod batch;
+mod lang_items;
+mod logging;
+mod sbi;
+mod sync;
+mod syscall;
+mod trap;
+
+core::arch::global_asm!(include_str!("entry.asm"));
+core::arch::global_asm!(include_str!("link_app.S"));
+
+fn clear_bss() {
+    extern "C" {
+        fn sbss();
+        fn ebss();
+    }
+    unsafe {
+        core::slice::from_raw_parts_mut(sbss as usize as *mut u8, ebss as usize - sbss as usize)
+            .fill(0);
+    }
+}
+
+#[no_mangle]
+pub fn rust_main() -> ! {
+    clear_bss();
+    logging::init();
+    println!("[kernel] Hello, world!");
+    trap::init();
+    batch::init();
+    batch::run_next_app();
+}

os2/src/sbi.rs

@@ -0,0 +1,34 @@
+#![allow(unused)]
+
+const SBI_SET_TIMER: usize = 0;
+const SBI_CONSOLE_PUTCHAR: usize = 1;
+const SBI_CONSOLE_GETCHAR: usize = 2;
+const SBI_SHUTDOWN: usize = 8;
+
+#[inline(always)]
+fn sbi_call(which: usize, arg0: usize, arg1: usize, arg2: usize) -> usize {
+    let mut ret;
+    unsafe {
+        core::arch::asm!(
+            "ecall",
+            inlateout("x10") arg0 => ret,
+            in("x11") arg1,
+            in("x12") arg2,
+            in("x17") which,
+        );
+    }
+    ret
+}
+
+pub fn console_putchar(c: usize) {
+    sbi_call(SBI_CONSOLE_PUTCHAR, c, 0, 0);
+}
+
+pub fn console_getchar() -> usize {
+    sbi_call(SBI_CONSOLE_GETCHAR, 0, 0, 0)
+}
+
+pub fn shutdown() -> ! {
+    sbi_call(SBI_SHUTDOWN, 0, 0, 0);
+    panic!("It should shutdown!");
+}

os2/src/sync/mod.rs

@@ -0,0 +1,3 @@
+mod up;
+
+pub use up::UPSafeCell;

os2/src/sync/up.rs

@@ -0,0 +1,29 @@
+use core::cell::{RefCell, RefMut};
+
+/// Wrap a static data structure inside it so that we are
+/// able to access it without any `unsafe`.
+///
+/// We should only use it in uniprocessor.
+///
+/// In order to get mutable reference of inner data, call
+/// `exclusive_access`.
+pub struct UPSafeCell<T> {
+    /// inner data
+    inner: RefCell<T>,
+}
+
+unsafe impl<T> Sync for UPSafeCell<T> {}
+
+impl<T> UPSafeCell<T> {
+    /// User is responsible to guarantee that inner struct is only used in
+    /// uniprocessor.
+    pub unsafe fn new(value: T) -> Self {
+        Self {
+            inner: RefCell::new(value),
+        }
+    }
+    /// Panic if the data has been borrowed.
+    pub fn exclusive_access(&self) -> RefMut<'_, T> {
+        self.inner.borrow_mut()
+    }
+}

os2/src/syscall/fs.rs

@@ -0,0 +1,15 @@
+const FD_STDOUT: usize = 1;
+
+pub fn sys_write(fd: usize, buf: *const u8, len: usize) -> isize {
+    match fd {
+        FD_STDOUT => {
+            let slice = unsafe { core::slice::from_raw_parts(buf, len) };
+            let str = core::str::from_utf8(slice).unwrap();
+            print!("{}", str);
+            len as isize
+        }
+        _ => {
+            panic!("Unsupported fd in sys_write!");
+        }
+    }
+}

os2/src/syscall/mod.rs

@@ -0,0 +1,16 @@
+const SYSCALL_WRITE: usize = 64;
+const SYSCALL_EXIT: usize = 93;
+
+mod fs;
+mod process;
+
+use fs::*;
+use 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),
+    }
+}

os2/src/syscall/process.rs

@@ -0,0 +1,6 @@
+use crate::batch::run_next_app;
+
+pub fn sys_exit(exit_code: i32) -> ! {
+    info!("[kernel] Application exited with code {}", exit_code);
+    run_next_app()
+}

os2/src/trap/context.rs

@@ -0,0 +1,25 @@
+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 mut sstatus = sstatus::read();
+        sstatus.set_spp(SPP::User);
+        let mut cx = Self {
+            x: [0; 32],
+            sstatus,
+            sepc: entry,
+        };
+        cx.set_sp(sp);
+        cx
+    }
+}

os2/src/trap/mod.rs

@@ -0,0 +1,50 @@
+mod context;
+
+use crate::batch::run_next_app;
+use crate::syscall::syscall;
+use riscv::register::{
+    mtvec::TrapMode,
+    scause::{self, Exception, Trap},
+    stval, stvec,
+};
+
+core::arch::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(Exception::UserEnvCall) => {
+            cx.sepc += 4;
+            cx.x[10] = syscall(cx.x[17], [cx.x[10], cx.x[11], cx.x[12]]) as usize;
+        }
+        Trap::Exception(Exception::StoreFault) | Trap::Exception(Exception::StorePageFault) => {
+            error!("[kernel] PageFault in application, core dumped.");
+            run_next_app();
+        }
+        Trap::Exception(Exception::IllegalInstruction) => {
+            error!("[kernel] IllegalInstruction in application, core dumped.");
+            run_next_app();
+        }
+        _ => {
+            panic!(
+                "Unsupported trap {:?}, stval = {:#x}!",
+                scause.cause(),
+                stval
+            );
+        }
+    }
+    cx
+}
+
+pub use context::TrapContext;

os2/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

os3/.cargo/config

@@ -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"
+]

os3/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "os"
+version = "0.1.0"
+authors = ["Yifan Wu <shinbokuow@163.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+buddy_system_allocator = "0.6"
+lazy_static = { version = "1.4.0", features = ["spin_no_std"] }
+log = "0.4"
+riscv = { git = "https://gitee.com/rcore-os/riscv", features = ["inline-asm"] }

os3/Makefile

@@ -0,0 +1,59 @@
+# Building
+TARGET := riscv64gc-unknown-none-elf
+MODE := release
+KERNEL_ELF := target/$(TARGET)/$(MODE)/os
+KERNEL_BIN := $(KERNEL_ELF).bin
+KERNEL_ASM := $(KERNEL_ELF).asm
+
+# BOARD
+BOARD ?= qemu
+SBI ?= rustsbi
+BOOTLOADER := ../bootloader/$(SBI)-$(BOARD).bin
+
+# KERNEL ENTRY
+KERNEL_ENTRY_PA := 0x80200000
+
+# Binutils
+OBJDUMP := rust-objdump --arch-name=riscv64
+OBJCOPY := rust-objcopy --binary-architecture=riscv64
+
+CHAPTER ?= 3
+TEST ?= $(CHAPTER)
+BASE ?= 1
+
+build: env $(KERNEL_BIN)
+
+$(KERNEL_BIN): kernel
+	@$(OBJCOPY) $(KERNEL_ELF) --strip-all -O binary $@
+	@$(OBJDUMP) $(KERNEL_ELF) -S > $(KERNEL_ELF).asm
+
+env:
+	(rustup target list | grep "riscv64gc-unknown-none-elf (installed)") || rustup target add $(TARGET)
+	cargo install cargo-binutils --vers ~0.2
+	rustup component add rust-src
+	rustup component add llvm-tools-preview
+
+$(KERNEL_BIN): kernel
+	@$(OBJCOPY) $(KERNEL_ELF) --strip-all -O binary $@
+
+kernel:
+	@make -C ../user build TEST=$(TEST) CHAPTER=$(CHAPTER) BASE=$(BASE)
+	@cargo build --release
+
+clean:
+	@cargo clean
+
+run: build
+	@qemu-system-riscv64 \
+		-machine virt \
+		-nographic \
+		-bios $(BOOTLOADER) \
+		-device loader,file=$(KERNEL_BIN),addr=$(KERNEL_ENTRY_PA)
+
+debug: build
+	@tmux new-session -d \
+		"qemu-system-riscv64 -machine virt -nographic -bios $(BOOTLOADER) -device loader,file=$(KERNEL_BIN),addr=$(KERNEL_ENTRY_PA) -s -S" && \
+		tmux split-window -h "riscv64-unknown-elf-gdb -ex 'file $(KERNEL_ELF)' -ex 'set arch riscv:rv64' -ex 'target remote localhost:1234'" && \
+		tmux -2 attach-session -d
+
+.PHONY: build env kernel clean run-inner

os3/build.rs

@@ -0,0 +1,56 @@
+use std::fs::{read_dir, File};
+use std::io::{Result, Write};
+
+fn main() {
+    println!("cargo:rerun-if-changed=../user/src/");
+    println!("cargo:rerun-if-changed={}", TARGET_PATH);
+    insert_app_data().unwrap();
+}
+
+static TARGET_PATH: &str = "../user/build/bin/";
+
+fn insert_app_data() -> Result<()> {
+    let mut f = File::create("src/link_app.S").unwrap();
+    let mut apps: Vec<_> = read_dir("../user/build/bin/")
+        .unwrap()
+        .into_iter()
+        .map(|dir_entry| {
+            let mut name_with_ext = dir_entry.unwrap().file_name().into_string().unwrap();
+            name_with_ext.drain(name_with_ext.find('.').unwrap()..name_with_ext.len());
+            name_with_ext
+        })
+        .collect();
+    apps.sort();
+
+    writeln!(
+        f,
+        r#"
+    .align 3
+    .section .data
+    .global _num_app
+_num_app:
+    .quad {}"#,
+        apps.len()
+    )?;
+
+    for i in 0..apps.len() {
+        writeln!(f, r#"    .quad app_{}_start"#, i)?;
+    }
+    writeln!(f, r#"    .quad app_{}_end"#, apps.len() - 1)?;
+
+    for (idx, app) in apps.iter().enumerate() {
+        println!("app_{}: {}", idx, app);
+        writeln!(
+            f,
+            r#"
+    .section .data
+    .global app_{0}_start
+    .global app_{0}_end
+app_{0}_start:
+    .incbin "{2}{1}.bin"
+app_{0}_end:"#,
+            idx, app, TARGET_PATH
+        )?;
+    }
+    Ok(())
+}

os3/src/config.rs

@@ -0,0 +1,8 @@
+pub const USER_STACK_SIZE: usize = 8192;
+pub const KERNEL_STACK_SIZE: usize = 8192 * 2;
+pub const KERNEL_HEAP_SIZE: usize = 0x20000;
+pub const MAX_APP_NUM: usize = 16;
+pub const APP_BASE_ADDRESS: usize = 0x80400000;
+pub const APP_SIZE_LIMIT: usize = 0x20000;
+pub const CLOCK_FREQ: usize = 12500000;
+pub const MAX_SYSCALL_NUM: usize = 500;

os3/src/console.rs

@@ -0,0 +1,31 @@
+use crate::sbi::console_putchar;
+use core::fmt::{self, Write};
+
+struct Stdout;
+
+impl Write for Stdout {
+    fn write_str(&mut self, s: &str) -> fmt::Result {
+        for c in s.chars() {
+            console_putchar(c as usize);
+        }
+        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)+)?));
+    }
+}

os3/src/entry.asm

@@ -0,0 +1,12 @@
+    .section .text.entry
+    .globl _start
+_start:
+    la sp, boot_stack_top
+    call rust_main
+
+    .section .bss.stack
+    .globl boot_stack
+boot_stack:
+    .space 4096 * 16
+    .globl boot_stack_top
+boot_stack_top:

os3/src/heap_alloc.rs

@@ -0,0 +1,20 @@
+use crate::config::KERNEL_HEAP_SIZE;
+use buddy_system_allocator::LockedHeap;
+
+#[global_allocator]
+static HEAP_ALLOCATOR: LockedHeap = LockedHeap::empty();
+
+static mut HEAP_SPACE: [u8; KERNEL_HEAP_SIZE] = [0; KERNEL_HEAP_SIZE];
+
+pub fn init_heap() {
+    unsafe {
+        HEAP_ALLOCATOR
+            .lock()
+            .init(HEAP_SPACE.as_ptr() as usize, KERNEL_HEAP_SIZE);
+    }
+}
+
+#[alloc_error_handler]
+pub fn handle_alloc_error(layout: core::alloc::Layout) -> ! {
+    panic!("Heap allocation error, layout = {:?}", layout);
+}

os3/src/lang_items.rs

@@ -0,0 +1,17 @@
+use crate::sbi::shutdown;
+use core::panic::PanicInfo;
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    if let Some(location) = info.location() {
+        println!(
+            "Panicked at {}:{} {}",
+            location.file(),
+            location.line(),
+            info.message().unwrap()
+        );
+    } else {
+        println!("[kernel] Panicked: {}", info.message().unwrap());
+    }
+    shutdown()
+}

os3/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 : {
+        *(.rodata .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)
+    }
+}

os3/src/loader.rs

@@ -0,0 +1,85 @@
+use crate::config::*;
+use crate::trap::TrapContext;
+
+#[repr(align(4096))]
+#[derive(Copy, Clone)]
+struct KernelStack {
+    data: [u8; KERNEL_STACK_SIZE],
+}
+
+#[repr(align(4096))]
+#[derive(Copy, Clone)]
+struct UserStack {
+    data: [u8; USER_STACK_SIZE],
+}
+
+static KERNEL_STACK: [KernelStack; MAX_APP_NUM] = [KernelStack {
+    data: [0; KERNEL_STACK_SIZE],
+}; MAX_APP_NUM];
+
+static USER_STACK: [UserStack; MAX_APP_NUM] = [UserStack {
+    data: [0; USER_STACK_SIZE],
+}; MAX_APP_NUM];
+
+impl KernelStack {
+    fn get_sp(&self) -> usize {
+        self.data.as_ptr() as usize + KERNEL_STACK_SIZE
+    }
+    pub fn push_context(&self, trap_cx: TrapContext) -> usize {
+        let trap_cx_ptr = (self.get_sp() - core::mem::size_of::<TrapContext>()) as *mut TrapContext;
+        unsafe {
+            *trap_cx_ptr = trap_cx;
+        }
+        trap_cx_ptr as usize
+    }
+}
+
+impl UserStack {
+    fn get_sp(&self) -> usize {
+        self.data.as_ptr() as usize + USER_STACK_SIZE
+    }
+}
+
+fn get_base_i(app_id: usize) -> usize {
+    APP_BASE_ADDRESS + app_id * APP_SIZE_LIMIT
+}
+
+pub fn get_num_app() -> usize {
+    extern "C" {
+        fn _num_app();
+    }
+    unsafe { (_num_app as usize as *const usize).read_volatile() }
+}
+
+pub fn load_apps() {
+    extern "C" {
+        fn _num_app();
+    }
+    let num_app_ptr = _num_app as usize as *const usize;
+    let num_app = get_num_app();
+    let app_start = unsafe { core::slice::from_raw_parts(num_app_ptr.add(1), num_app + 1) };
+    // clear i-cache first
+    unsafe {
+        core::arch::asm!("fence.i");
+    }
+    // load apps
+    for i in 0..num_app {
+        let base_i = get_base_i(i);
+        // clear region
+        (base_i..base_i + APP_SIZE_LIMIT)
+            .for_each(|addr| unsafe { (addr as *mut u8).write_volatile(0) });
+        // load app from data section to memory
+        let src = unsafe {
+            core::slice::from_raw_parts(app_start[i] as *const u8, app_start[i + 1] - app_start[i])
+        };
+        let dst = unsafe { core::slice::from_raw_parts_mut(base_i as *mut u8, src.len()) };
+        dst.copy_from_slice(src);
+    }
+}
+
+pub fn init_app_cx(app_id: usize) -> usize {
+    KERNEL_STACK[app_id].push_context(TrapContext::app_init_context(
+        get_base_i(app_id),
+        USER_STACK[app_id].get_sp(),
+    ))
+}

os3/src/logging.rs

@@ -0,0 +1,41 @@
+use log::{self, Level, LevelFilter, Log, Metadata, Record};
+
+struct SimpleLogger;
+
+impl Log for SimpleLogger {
+    fn enabled(&self, _metadata: &Metadata) -> bool {
+        true
+    }
+    fn log(&self, record: &Record) {
+        if !self.enabled(record.metadata()) {
+            return;
+        }
+        let color = match record.level() {
+            Level::Error => 31, // Red
+            Level::Warn => 93,  // BrightYellow
+            Level::Info => 34,  // Blue
+            Level::Debug => 32, // Green
+            Level::Trace => 90, // BrightBlack
+        };
+        println!(
+            "\u{1B}[{}m[{:>5}] {}\u{1B}[0m",
+            color,
+            record.level(),
+            record.args(),
+        );
+    }
+    fn flush(&self) {}
+}
+
+pub fn init() {
+    static LOGGER: SimpleLogger = SimpleLogger;
+    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,
+    });
+}

os3/src/main.rs

@@ -0,0 +1,51 @@
+#![no_std]
+#![no_main]
+#![feature(panic_info_message)]
+#![feature(alloc_error_handler)]
+
+#[macro_use]
+extern crate log;
+
+extern crate alloc;
+
+#[macro_use]
+mod console;
+mod config;
+mod heap_alloc;
+mod lang_items;
+mod loader;
+mod logging;
+mod sbi;
+mod sync;
+mod syscall;
+mod task;
+mod timer;
+mod trap;
+
+core::arch::global_asm!(include_str!("entry.asm"));
+core::arch::global_asm!(include_str!("link_app.S"));
+
+fn clear_bss() {
+    extern "C" {
+        fn sbss();
+        fn ebss();
+    }
+    unsafe {
+        core::slice::from_raw_parts_mut(sbss as usize as *mut u8, ebss as usize - sbss as usize)
+            .fill(0);
+    }
+}
+
+#[no_mangle]
+pub fn rust_main() -> ! {
+    clear_bss();
+    logging::init();
+    println!("[kernel] Hello, world!");
+    heap_alloc::init_heap();
+    trap::init();
+    loader::load_apps();
+    trap::enable_timer_interrupt();
+    timer::set_next_trigger();
+    task::run_first_task();
+    panic!("Unreachable in rust_main!");
+}

os3/src/sbi.rs

@@ -0,0 +1,38 @@
+#![allow(unused)]
+
+const SBI_SET_TIMER: usize = 0;
+const SBI_CONSOLE_PUTCHAR: usize = 1;
+const SBI_CONSOLE_GETCHAR: usize = 2;
+const SBI_SHUTDOWN: usize = 8;
+
+#[inline(always)]
+fn sbi_call(which: usize, arg0: usize, arg1: usize, arg2: usize) -> usize {
+    let mut ret;
+    unsafe {
+        core::arch::asm!(
+            "ecall",
+            inlateout("x10") arg0 => ret,
+            in("x11") arg1,
+            in("x12") arg2,
+            in("x17") which,
+        );
+    }
+    ret
+}
+
+pub fn set_timer(timer: usize) {
+    sbi_call(SBI_SET_TIMER, timer, 0, 0);
+}
+
+pub fn console_putchar(c: usize) {
+    sbi_call(SBI_CONSOLE_PUTCHAR, c, 0, 0);
+}
+
+pub fn console_getchar() -> usize {
+    sbi_call(SBI_CONSOLE_GETCHAR, 0, 0, 0)
+}
+
+pub fn shutdown() -> ! {
+    sbi_call(SBI_SHUTDOWN, 0, 0, 0);
+    panic!("It should shutdown!");
+}

os3/src/timer.rs

@@ -0,0 +1,18 @@
+use crate::config::CLOCK_FREQ;
+use crate::sbi::set_timer;
+use riscv::register::time;
+
+const TICKS_PER_SEC: usize = 100;
+const MICRO_PER_SEC: usize = 1_000_000;
+
+pub fn get_time() -> usize {
+    time::read()
+}
+
+pub fn get_time_us() -> usize {
+    time::read() / (CLOCK_FREQ / MICRO_PER_SEC)
+}
+
+pub fn set_next_trigger() {
+    set_timer(get_time() + CLOCK_FREQ / TICKS_PER_SEC);
+}

os4/.cargo/config

@@ -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"
+]

os4/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "os"
+version = "0.1.0"
+authors = ["Yifan Wu <shinbokuow@163.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+bitflags = "1.2.1"
+buddy_system_allocator = "0.6"
+lazy_static = { version = "1.4.0", features = ["spin_no_std"] }
+log = "0.4"
+riscv = { git = "https://gitee.com/rcore-os/riscv", features = ["inline-asm"] }
+spin = "0.9"
+lock_api = "=0.4.6"
+xmas-elf = "0.7.0"

os4/Makefile

@@ -0,0 +1,51 @@
+# Building
+TARGET := riscv64gc-unknown-none-elf
+MODE := release
+KERNEL_ELF := target/$(TARGET)/$(MODE)/os
+KERNEL_BIN := $(KERNEL_ELF).bin
+
+# BOARD
+BOARD ?= qemu
+SBI ?= rustsbi
+BOOTLOADER := ../bootloader/$(SBI)-$(BOARD).bin
+
+# KERNEL ENTRY
+KERNEL_ENTRY_PA := 0x80200000
+
+# Binutils
+OBJDUMP := rust-objdump --arch-name=riscv64
+OBJCOPY := rust-objcopy --binary-architecture=riscv64
+
+TEST ?= 0
+build: env $(KERNEL_BIN)
+
+env:
+	(rustup target list | grep "riscv64gc-unknown-none-elf (installed)") || rustup target add $(TARGET)
+	cargo install cargo-binutils --vers ~0.2
+	rustup component add rust-src
+	rustup component add llvm-tools-preview
+
+$(KERNEL_BIN): kernel
+	@$(OBJCOPY) $(KERNEL_ELF) --strip-all -O binary $@
+
+kernel:
+	@cd ../user && make build TEST=$(TEST)
+	@cargo build --release
+
+clean:
+	@cargo clean
+
+run: build
+	@qemu-system-riscv64 \
+		-machine virt \
+		-nographic \
+		-bios $(BOOTLOADER) \
+		-device loader,file=$(KERNEL_BIN),addr=$(KERNEL_ENTRY_PA)
+
+debug: build
+	@tmux new-session -d \
+		"qemu-system-riscv64 -machine virt -nographic -bios $(BOOTLOADER) -device loader,file=$(KERNEL_BIN),addr=$(KERNEL_ENTRY_PA) -s -S" && \
+		tmux split-window -h "riscv64-unknown-elf-gdb -ex 'file $(KERNEL_ELF)' -ex 'set arch riscv:rv64' -ex 'target remote localhost:1234'" && \
+		tmux -2 attach-session -d
+
+.PHONY: build env kernel clean run-inner

os4/build.rs

@@ -0,0 +1,57 @@
+use std::fs::{read_dir, File};
+use std::io::{Result, Write};
+
+fn main() {
+    println!("cargo:rerun-if-changed=../user/src/");
+    println!("cargo:rerun-if-changed={}", TARGET_PATH);
+    insert_app_data().unwrap();
+}
+
+static TARGET_PATH: &str = "../user/build/elf/";
+
+fn insert_app_data() -> Result<()> {
+    let mut f = File::create("src/link_app.S").unwrap();
+    let mut apps: Vec<_> = read_dir("../user/build/elf/")
+        .unwrap()
+        .into_iter()
+        .map(|dir_entry| {
+            let mut name_with_ext = dir_entry.unwrap().file_name().into_string().unwrap();
+            name_with_ext.drain(name_with_ext.find('.').unwrap()..name_with_ext.len());
+            name_with_ext
+        })
+        .collect();
+    apps.sort();
+
+    writeln!(
+        f,
+        r#"
+    .align 3
+    .section .data
+    .global _num_app
+_num_app:
+    .quad {}"#,
+        apps.len()
+    )?;
+
+    for i in 0..apps.len() {
+        writeln!(f, r#"    .quad app_{}_start"#, i)?;
+    }
+    writeln!(f, r#"    .quad app_{}_end"#, apps.len() - 1)?;
+
+    for (idx, app) in apps.iter().enumerate() {
+        println!("app_{}: {}", idx, app);
+        writeln!(
+            f,
+            r#"
+    .section .data
+    .global app_{0}_start
+    .global app_{0}_end
+    .align 3
+app_{0}_start:
+    .incbin "{2}{1}.elf"
+app_{0}_end:"#,
+            idx, app, TARGET_PATH
+        )?;
+    }
+    Ok(())
+}

os4/src/config.rs

@@ -0,0 +1,18 @@
+pub const USER_STACK_SIZE: usize = 4096 * 2;
+pub const KERNEL_STACK_SIZE: usize = 4096 * 2;
+pub const KERNEL_HEAP_SIZE: usize = 0x30_0000;
+pub const MEMORY_END: usize = 0x88000000;
+pub const PAGE_SIZE: usize = 0x1000;
+pub const PAGE_SIZE_BITS: usize = 0xc;
+pub const MAX_SYSCALL_NUM: usize = 500;
+
+pub const TRAMPOLINE: usize = usize::MAX - PAGE_SIZE + 1;
+pub const TRAP_CONTEXT: usize = TRAMPOLINE - PAGE_SIZE;
+/// Return (bottom, top) of a kernel stack in kernel space.
+pub fn kernel_stack_position(app_id: usize) -> (usize, usize) {
+    let top = TRAMPOLINE - app_id * (KERNEL_STACK_SIZE + PAGE_SIZE);
+    let bottom = top - KERNEL_STACK_SIZE;
+    (bottom, top)
+}
+
+pub const CLOCK_FREQ: usize = 12500000;

os4/src/console.rs

@@ -0,0 +1,35 @@
+/*！
+    本模块实现了 print 和 println 宏
+*/
+
+use crate::sbi::console_putchar;
+use core::fmt::{self, Write};
+
+struct Stdout;
+
+impl Write for Stdout {
+    fn write_str(&mut self, s: &str) -> fmt::Result {
+        for c in s.chars() {
+            console_putchar(c as usize);
+        }
+        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)+)?));
+    }
+}

os4/src/entry.asm

@@ -0,0 +1,12 @@
+    .section .text.entry
+    .globl _start
+_start:
+    la sp, boot_stack_top
+    call rust_main
+
+    .section .bss.stack
+    .globl boot_stack
+boot_stack:
+    .space 4096 * 16
+    .globl boot_stack_top
+boot_stack_top:

os4/src/lang_items.rs

@@ -0,0 +1,17 @@
+use crate::sbi::shutdown;
+use core::panic::PanicInfo;
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    if let Some(location) = info.location() {
+        println!(
+            "Panicked at {}:{} {}",
+            location.file(),
+            location.line(),
+            info.message().unwrap()
+        );
+    } else {
+        println!("[kernel] Panicked: {}", info.message().unwrap());
+    }
+    shutdown()
+}

os4/src/linker.ld

@@ -0,0 +1,53 @@
+OUTPUT_ARCH(riscv)
+ENTRY(_start)
+BASE_ADDRESS = 0x80200000;
+
+SECTIONS
+{
+    . = BASE_ADDRESS;
+    skernel = .;
+
+    stext = .;
+    .text : {
+        *(.text.entry)
+        . = ALIGN(4K);
+        strampoline = .;
+        *(.text.trampoline);
+        . = ALIGN(4K);
+        *(.text .text.*)
+    }
+
+    . = ALIGN(4K);
+    etext = .;
+    srodata = .;
+    .rodata : {
+        *(.rodata .rodata.*)
+        *(.srodata .srodata.*)
+    }
+
+    . = ALIGN(4K);
+    erodata = .;
+    sdata = .;
+    .data : {
+        *(.data .data.*)
+        *(.sdata .sdata.*)
+    }
+
+    . = ALIGN(4K);
+    edata = .;
+    sbss_with_stack = .;
+    .bss : {
+        *(.bss.stack)
+        sbss = .;
+        *(.bss .bss.*)
+        *(.sbss .sbss.*)
+    }
+
+    . = ALIGN(4K);
+    ebss = .;
+    ekernel = .;
+
+    /DISCARD/ : {
+        *(.eh_frame)
+    }
+}

os4/src/loader.rs

@@ -0,0 +1,22 @@
+pub fn get_num_app() -> usize {
+    extern "C" {
+        fn _num_app();
+    }
+    unsafe { (_num_app as usize as *const usize).read_volatile() }
+}
+
+pub fn get_app_data(app_id: usize) -> &'static [u8] {
+    extern "C" {
+        fn _num_app();
+    }
+    let num_app_ptr = _num_app as usize as *const usize;
+    let num_app = get_num_app();
+    let app_start = unsafe { core::slice::from_raw_parts(num_app_ptr.add(1), num_app + 1) };
+    assert!(app_id < num_app);
+    unsafe {
+        core::slice::from_raw_parts(
+            app_start[app_id] as *const u8,
+            app_start[app_id + 1] - app_start[app_id],
+        )
+    }
+}

os4/src/logging.rs

@@ -0,0 +1,41 @@
+use log::{self, Level, LevelFilter, Log, Metadata, Record};
+
+struct SimpleLogger;
+
+impl Log for SimpleLogger {
+    fn enabled(&self, _metadata: &Metadata) -> bool {
+        true
+    }
+    fn log(&self, record: &Record) {
+        if !self.enabled(record.metadata()) {
+            return;
+        }
+        let color = match record.level() {
+            Level::Error => 31, // Red
+            Level::Warn => 93,  // BrightYellow
+            Level::Info => 34,  // Blue
+            Level::Debug => 32, // Green
+            Level::Trace => 90, // BrightBlack
+        };
+        println!(
+            "\u{1B}[{}m[{:>5}] {}\u{1B}[0m",
+            color,
+            record.level(),
+            record.args(),
+        );
+    }
+    fn flush(&self) {}
+}
+
+pub fn init() {
+    static LOGGER: SimpleLogger = SimpleLogger;
+    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,
+    });
+}

os4/src/main.rs

@@ -0,0 +1,55 @@
+#![no_std]
+#![no_main]
+#![feature(panic_info_message)]
+#![feature(alloc_error_handler)]
+
+#[macro_use]
+extern crate bitflags;
+#[macro_use]
+extern crate log;
+
+extern crate alloc;
+
+#[macro_use]
+mod console;
+mod config;
+mod lang_items;
+mod loader;
+mod logging;
+mod mm;
+mod sbi;
+mod sync;
+mod syscall;
+mod task;
+mod timer;
+mod trap;
+
+core::arch::global_asm!(include_str!("entry.asm"));
+core::arch::global_asm!(include_str!("link_app.S"));
+
+fn clear_bss() {
+    extern "C" {
+        fn sbss();
+        fn ebss();
+    }
+    unsafe {
+        core::slice::from_raw_parts_mut(sbss as usize as *mut u8, ebss as usize - sbss as usize)
+            .fill(0);
+    }
+}
+
+#[no_mangle]
+pub fn rust_main() -> ! {
+    clear_bss();
+    logging::init();
+    println!("[kernel] Hello, world!");
+    mm::init();
+    println!("[kernel] back to world!");
+    mm::remap_test();
+    trap::init();
+    //trap::enable_interrupt();
+    trap::enable_timer_interrupt();
+    timer::set_next_trigger();
+    task::run_first_task();
+    panic!("Unreachable in rust_main!");
+}

os4/src/sbi.rs

@@ -0,0 +1,38 @@
+#![allow(unused)]
+
+const SBI_SET_TIMER: usize = 0;
+const SBI_CONSOLE_PUTCHAR: usize = 1;
+const SBI_CONSOLE_GETCHAR: usize = 2;
+const SBI_SHUTDOWN: usize = 8;
+
+#[inline(always)]
+fn sbi_call(which: usize, arg0: usize, arg1: usize, arg2: usize) -> usize {
+    let mut ret;
+    unsafe {
+        core::arch::asm!(
+            "ecall",
+            inlateout("x10") arg0 => ret,
+            in("x11") arg1,
+            in("x12") arg2,
+            in("x17") which,
+        );
+    }
+    ret
+}
+
+pub fn set_timer(timer: usize) {
+    sbi_call(SBI_SET_TIMER, timer, 0, 0);
+}
+
+pub fn console_putchar(c: usize) {
+    sbi_call(SBI_CONSOLE_PUTCHAR, c, 0, 0);
+}
+
+pub fn console_getchar() -> usize {
+    sbi_call(SBI_CONSOLE_GETCHAR, 0, 0, 0)
+}
+
+pub fn shutdown() -> ! {
+    sbi_call(SBI_SHUTDOWN, 0, 0, 0);
+    panic!("It should shutdown!");
+}

os4/src/timer.rs

@@ -0,0 +1,18 @@
+use crate::config::CLOCK_FREQ;
+use crate::sbi::set_timer;
+use riscv::register::time;
+
+const TICKS_PER_SEC: usize = 100;
+const MICRO_PER_SEC: usize = 1_000_000;
+
+pub fn get_time() -> usize {
+    time::read()
+}
+
+pub fn get_time_us() -> usize {
+    time::read() / (CLOCK_FREQ / MICRO_PER_SEC)
+}
+
+pub fn set_next_trigger() {
+    set_timer(get_time() + CLOCK_FREQ / TICKS_PER_SEC);
+}

os5/.cargo/config

@@ -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"
+]

os5/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "os"
+version = "0.1.0"
+authors = ["Yifan Wu <shinbokuow@163.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+bitflags = "1.2.1"
+buddy_system_allocator = "0.6"
+lazy_static = { version = "1.4.0", features = ["spin_no_std"] }
+log = "0.4"
+riscv = { git = "https://gitee.com/rcore-os/riscv", features = ["inline-asm"] }
+spin = "0.9"
+xmas-elf = "0.7.0"
+lock_api = "=0.4.6"

os5/Makefile

@@ -0,0 +1,55 @@
+# Building
+TARGET := riscv64gc-unknown-none-elf
+MODE := release
+KERNEL_ELF := target/$(TARGET)/$(MODE)/os
+KERNEL_BIN := $(KERNEL_ELF).bin
+KERNEL_ASM := $(KERNEL_ELF).asm
+
+# BOARD
+BOARD ?= qemu
+SBI ?= rustsbi
+BOOTLOADER := ../bootloader/$(SBI)-$(BOARD).bin
+
+# KERNEL ENTRY
+KERNEL_ENTRY_PA := 0x80200000
+
+# Binutils
+OBJDUMP := rust-objdump --arch-name=riscv64
+OBJCOPY := rust-objcopy --binary-architecture=riscv64
+
+CHAPTER ?= 5
+TEST ?= $(CHAPTER)
+BASE ?= 1
+
+build: env $(KERNEL_BIN)
+
+env:
+	(rustup target list | grep "riscv64gc-unknown-none-elf (installed)") || rustup target add $(TARGET)
+	cargo install cargo-binutils --vers ~0.3
+	rustup component add rust-src
+	rustup component add llvm-tools-preview
+
+$(KERNEL_BIN): kernel
+	@$(OBJCOPY) $(KERNEL_ELF) --strip-all -O binary $@
+
+kernel:
+	@make -C ../user build TEST=$(TEST) CHAPTER=$(CHAPTER) BASE=$(BASE)
+	@cargo build --release
+
+clean:
+	@cargo clean
+
+run: build
+	@qemu-system-riscv64 \
+		-machine virt \
+		-nographic \
+		-bios $(BOOTLOADER) \
+		-device loader,file=$(KERNEL_BIN),addr=$(KERNEL_ENTRY_PA)
+
+debug: build
+	@tmux new-session -d \
+		"qemu-system-riscv64 -machine virt -nographic -bios $(BOOTLOADER) -device loader,file=$(KERNEL_BIN),addr=$(KERNEL_ENTRY_PA) -s -S" && \
+		tmux split-window -h "riscv64-unknown-elf-gdb -ex 'file $(KERNEL_ELF)' -ex 'set arch riscv:rv64' -ex 'target remote localhost:1234'" && \
+		tmux -2 attach-session -d
+
+.PHONY: build env kernel clean run-inner

os5/build.rs

@@ -0,0 +1,67 @@
+use std::fs::{read_dir, File};
+use std::io::{Result, Write};
+
+fn main() {
+    println!("cargo:rerun-if-changed=../user/src/");
+    println!("cargo:rerun-if-changed={}", TARGET_PATH);
+    insert_app_data().unwrap();
+}
+
+static TARGET_PATH: &str = "../user/build/elf/";
+
+fn insert_app_data() -> Result<()> {
+    let mut f = File::create("src/link_app.S").unwrap();
+    let mut apps: Vec<_> = read_dir("../user/build/elf/")
+        .unwrap()
+        .into_iter()
+        .map(|dir_entry| {
+            let mut name_with_ext = dir_entry.unwrap().file_name().into_string().unwrap();
+            name_with_ext.drain(name_with_ext.find('.').unwrap()..name_with_ext.len());
+            name_with_ext
+        })
+        .collect();
+    apps.sort();
+
+    writeln!(
+        f,
+        r#"
+    .align 3
+    .section .data
+    .global _num_app
+_num_app:
+    .quad {}"#,
+        apps.len()
+    )?;
+
+    for i in 0..apps.len() {
+        writeln!(f, r#"    .quad app_{}_start"#, i)?;
+    }
+    writeln!(f, r#"    .quad app_{}_end"#, apps.len() - 1)?;
+
+    writeln!(
+        f,
+        r#"
+    .global _app_names
+_app_names:"#
+    )?;
+    for app in apps.iter() {
+        writeln!(f, r#"    .string "{}""#, app)?;
+    }
+
+    for (idx, app) in apps.iter().enumerate() {
+        println!("app_{}: {}", idx, app);
+        writeln!(
+            f,
+            r#"
+    .section .data
+    .global app_{0}_start
+    .global app_{0}_end
+    .align 3
+app_{0}_start:
+    .incbin "{2}{1}.elf"
+app_{0}_end:"#,
+            idx, app, TARGET_PATH
+        )?;
+    }
+    Ok(())
+}

os5/src/config.rs

@@ -0,0 +1,12 @@
+pub const USER_STACK_SIZE: usize = 4096 * 2;
+pub const KERNEL_STACK_SIZE: usize = 4096 * 2;
+pub const KERNEL_HEAP_SIZE: usize = 0x30_0000;
+pub const MEMORY_END: usize = 0x88000000;
+pub const PAGE_SIZE: usize = 0x1000;
+pub const PAGE_SIZE_BITS: usize = 0xc;
+pub const MAX_SYSCALL_NUM: usize = 500;
+pub const BIG_STRIDE: usize = usize::MAX;
+
+pub const TRAMPOLINE: usize = usize::MAX - PAGE_SIZE + 1;
+pub const TRAP_CONTEXT: usize = TRAMPOLINE - PAGE_SIZE;
+pub const CLOCK_FREQ: usize = 12500000;

os5/src/console.rs

@@ -0,0 +1,35 @@
+/*！
+    本模块实现了 print 和 println 宏
+*/
+
+use crate::sbi::console_putchar;
+use core::fmt::{self, Write};
+
+struct Stdout;
+
+impl Write for Stdout {
+    fn write_str(&mut self, s: &str) -> fmt::Result {
+        for c in s.chars() {
+            console_putchar(c as usize);
+        }
+        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)+)?));
+    }
+}

os5/src/entry.asm

@@ -0,0 +1,12 @@
+    .section .text.entry
+    .globl _start
+_start:
+    la sp, boot_stack_top
+    call rust_main
+
+    .section .bss.stack
+    .globl boot_stack
+boot_stack:
+    .space 4096 * 16
+    .globl boot_stack_top
+boot_stack_top:

os5/src/lang_items.rs

@@ -0,0 +1,17 @@
+use crate::sbi::shutdown;
+use core::panic::PanicInfo;
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    if let Some(location) = info.location() {
+        println!(
+            "Panicked at {}:{} {}",
+            location.file(),
+            location.line(),
+            info.message().unwrap()
+        );
+    } else {
+        println!("[kernel] Panicked: {}", info.message().unwrap());
+    }
+    shutdown()
+}

os5/src/linker.ld

@@ -0,0 +1,53 @@
+OUTPUT_ARCH(riscv)
+ENTRY(_start)
+BASE_ADDRESS = 0x80200000;
+
+SECTIONS
+{
+    . = BASE_ADDRESS;
+    skernel = .;
+
+    stext = .;
+    .text : {
+        *(.text.entry)
+        . = ALIGN(4K);
+        strampoline = .;
+        *(.text.trampoline);
+        . = ALIGN(4K);
+        *(.text .text.*)
+    }
+
+    . = ALIGN(4K);
+    etext = .;
+    srodata = .;
+    .rodata : {
+        *(.rodata .rodata.*)
+        *(.srodata .srodata.*)
+    }
+
+    . = ALIGN(4K);
+    erodata = .;
+    sdata = .;
+    .data : {
+        *(.data .data.*)
+        *(.sdata .sdata.*)
+    }
+
+    . = ALIGN(4K);
+    edata = .;
+    sbss_with_stack = .;
+    .bss : {
+        *(.bss.stack)
+        sbss = .;
+        *(.bss .bss.*)
+        *(.sbss .sbss.*)
+    }
+
+    . = ALIGN(4K);
+    ebss = .;
+    ekernel = .;
+
+    /DISCARD/ : {
+        *(.eh_frame)
+    }
+}

os5/src/loader.rs

@@ -0,0 +1,64 @@
+use alloc::vec::Vec;
+use lazy_static::*;
+
+pub fn get_num_app() -> usize {
+    extern "C" {
+        fn _num_app();
+    }
+    unsafe { (_num_app as usize as *const usize).read_volatile() }
+}
+
+pub fn get_app_data(app_id: usize) -> &'static [u8] {
+    extern "C" {
+        fn _num_app();
+    }
+    let num_app_ptr = _num_app as usize as *const usize;
+    let num_app = get_num_app();
+    let app_start = unsafe { core::slice::from_raw_parts(num_app_ptr.add(1), num_app + 1) };
+    assert!(app_id < num_app);
+    unsafe {
+        core::slice::from_raw_parts(
+            app_start[app_id] as *const u8,
+            app_start[app_id + 1] - app_start[app_id],
+        )
+    }
+}
+
+lazy_static! {
+    static ref APP_NAMES: Vec<&'static str> = {
+        let num_app = get_num_app();
+        extern "C" {
+            fn _app_names();
+        }
+        let mut start = _app_names as usize as *const u8;
+        let mut v = Vec::new();
+        unsafe {
+            for _ in 0..num_app {
+                let mut end = start;
+                while end.read_volatile() != b'\0' {
+                    end = end.add(1);
+                }
+                let slice = core::slice::from_raw_parts(start, end as usize - start as usize);
+                let str = core::str::from_utf8(slice).unwrap();
+                v.push(str);
+                start = end.add(1);
+            }
+        }
+        v
+    };
+}
+
+pub fn get_app_data_by_name(name: &str) -> Option<&'static [u8]> {
+    let num_app = get_num_app();
+    (0..num_app)
+        .find(|&i| APP_NAMES[i] == name)
+        .map(get_app_data)
+}
+
+pub fn list_apps() {
+    println!("/**** APPS ****");
+    for app in APP_NAMES.iter() {
+        println!("{}", app);
+    }
+    println!("**************/");
+}

os5/src/logging.rs

@@ -0,0 +1,41 @@
+use log::{self, Level, LevelFilter, Log, Metadata, Record};
+
+struct SimpleLogger;
+
+impl Log for SimpleLogger {
+    fn enabled(&self, _metadata: &Metadata) -> bool {
+        true
+    }
+    fn log(&self, record: &Record) {
+        if !self.enabled(record.metadata()) {
+            return;
+        }
+        let color = match record.level() {
+            Level::Error => 31, // Red
+            Level::Warn => 93,  // BrightYellow
+            Level::Info => 34,  // Blue
+            Level::Debug => 32, // Green
+            Level::Trace => 90, // BrightBlack
+        };
+        println!(
+            "\u{1B}[{}m[{:>5}] {}\u{1B}[0m",
+            color,
+            record.level(),
+            record.args(),
+        );
+    }
+    fn flush(&self) {}
+}
+
+pub fn init() {
+    static LOGGER: SimpleLogger = SimpleLogger;
+    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,
+    });
+}

os5/src/main.rs

@@ -0,0 +1,56 @@
+#![no_std]
+#![no_main]
+#![feature(panic_info_message)]
+#![feature(alloc_error_handler)]
+
+#[macro_use]
+extern crate bitflags;
+#[macro_use]
+extern crate log;
+
+extern crate alloc;
+
+#[macro_use]
+mod console;
+mod config;
+mod lang_items;
+mod loader;
+mod logging;
+mod mm;
+mod sbi;
+mod sync;
+mod syscall;
+mod task;
+mod timer;
+mod trap;
+
+core::arch::global_asm!(include_str!("entry.asm"));
+core::arch::global_asm!(include_str!("link_app.S"));
+
+fn clear_bss() {
+    extern "C" {
+        fn sbss();
+        fn ebss();
+    }
+    unsafe {
+        core::slice::from_raw_parts_mut(sbss as usize as *mut u8, ebss as usize - sbss as usize)
+            .fill(0);
+    }
+}
+
+#[no_mangle]
+pub fn rust_main() -> ! {
+    clear_bss();
+    logging::init();
+    println!("[kernel] Hello, world!");
+    mm::init();
+    mm::remap_test();
+    task::add_initproc();
+    info!("after initproc!");
+    trap::init();
+    trap::enable_timer_interrupt();
+    timer::set_next_trigger();
+    loader::list_apps();
+    task::run_tasks();
+    panic!("Unreachable in rust_main!");
+}