feat: add file system

docs/实验手册.md

@@ -132,3 +132,88 @@ TLB 表项的比较部分包括:
 
 ![image-20220707161012062](sourcepicture/image-20220707161012062.png)
 
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+
+# 第五章
+
+### 问题1: 在用户程序`matrix`实现中，如果是如下的代码:
+
+```rust
+println!("pid {} is running ({} times)!.", getpid(), times);
+```
+
+则会造成页错误,如果改成如下的代码:
+
+```rust
+println!("yield began");
+yield_();
+println!("pid {} is running ({} times)!.", getpid(), times);
+```
+
+则会运行通过。
+
+
+
+解决思路1: 在任务切换时是否正确进行了相关寄存器的设置？
+
+实际效果: 以第一种代码为例，在设置正确寄存器后，虽然可以正常打印这句话，但是后面仍然会造成指令不存在的错误
+
+解决思路2：删除掉第二中的添加的打印语句，改成如下的语句:
+
+```rust
+let mut i = 2;
+yield_();
+println!("pid {} is running ({} times {})!.", getpid(), times,i);
+```
+
+效果:
+
+在这种情况下，将会发生访问的地址出现错误的情况，此时出错地址不在正常的地址空间中。
+
+==debug过程:==
+
+在TLB重填处理函数中将出错地址打印出来，通过观察，此地址应该属于内核区域，因此不会在对应的应用程序的地址空间找到对应的页表项。而应用程序这里出错的位置是打印函数`println`，因此推测可能是`print`函数实现有错误，再去查看rcore的源代码后发现`print/println`的实现确实有过更改，因此这里就暂时将实现修改，在测试后发现居然可以正常运行了，因此就需要仔细对比前后两者的实现了。
+
+老版本实现：
+
+```rust
+#[macro_export]
+macro_rules! print {
+    ($($arg:tt)*) => ($crate::print::_print(format_args!($($arg)*)));
+}
+#[macro_export]
+macro_rules! println {
+    () => ($crate::print!("\n"));
+    ($($arg:tt)*) => ($crate::print!("{}\n", format_args!($($arg)*)));
+}
+```
+
+新版本实现:
+
+```rust
+macro_rules! print {
+    ($fmt: literal $(, $($arg: tt)+)?) => {
+        $crate::print::_print(format_args!($fmt $(, $($arg)+)?));
+    }
+}
+
+#[macro_export]
+/// println string macro
+macro_rules! println {
+    ($fmt: literal $(, $($arg: tt)+)?) => {
+        $crate::print::_print(format_args!(concat!($fmt, "\n") $(, $($arg)+)?));
+    }
+}
+
+```
+
+两者实现差异:
+

easy-fs-fuse/.gitignore

@@ -0,0 +1,13 @@
+### Rust template
+# Generated by Cargo
+# will have compiled files and executables
+debug/
+target/
+
+# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
+# More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html
+Cargo.lock
+
+# These are backup files generated by rustfmt
+**/*.rs.bk
+

easy-fs-fuse/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name = "easy-fs-fuse"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+clap = "3.0.14"
+rand = "0.8.4"
+easy-fs = {path = "../easy-fs"}

easy-fs-fuse/src/main.rs

@@ -0,0 +1,152 @@
+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;
+
+const BLOCK_SZ: usize = 512;
+
+struct BlockFile(Mutex<File>);
+
+impl BlockDevice for BlockFile {
+    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!");
+    }
+
+    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 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(16 * 2048 * 512).unwrap();
+        f
+    })));
+    // 16MiB, at most 4095 files
+    let efs = EasyFileSystem::create(block_file, 16 * 2048, 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 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(8192 * 512).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; 512];
+    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(())
+}
+
+fn main() {
+    easy_fs_pack().expect("Error when packing easy-fs!");
+}

easy-fs/.gitignore

@@ -0,0 +1,15 @@
+### Rust template
+# Generated by Cargo
+# will have compiled files and executables
+debug/
+target/
+
+# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
+# More information here https://doc.rust-lang.org/cargo/guide/cargo-toml-vs-cargo-lock.html
+Cargo.lock
+
+# These are backup files generated by rustfmt
+**/*.rs.bk
+
+
+

easy-fs/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "easy-fs"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+spin = "0.9.2"
+lazy_static = {version = "1.4.0", features = ["spin_no_std"]}
+
+
+[profile.release]
+debug = true