Init the ch4

Author: Azure-stars

.gitignore

@@ -15,6 +15,7 @@ easy-fs-fuse/target/*
 tools/
 pushall.sh
 *.bak
+
 ci-user/
+os/vendor/
 user/
-os/vendor/

os/Cargo.toml

@@ -7,7 +7,9 @@ edition = "2021"
 # 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://github.com/rcore-os/riscv", features = ["inline-asm"] }
+xmas-elf = "0.7.0"

os/build.rs

@@ -9,12 +9,12 @@ fn main() {
     insert_app_data().unwrap();
 }
 
-static TARGET_PATH: &str = "../user/build/bin/";
+static TARGET_PATH: &str = "../user/build/elf/";
 
 /// get app data and build linker
 fn insert_app_data() -> Result<()> {
     let mut f = File::create("src/link_app.S").unwrap();
-    let mut apps: Vec<_> = read_dir("../user/build/bin/")
+    let mut apps: Vec<_> = read_dir("../user/build/elf/")
         .unwrap()
         .into_iter()
         .map(|dir_entry| {
@@ -49,8 +49,9 @@ _num_app:
     .section .data
     .global app_{0}_start
     .global app_{0}_end
+    .align 3
 app_{0}_start:
-    .incbin "{2}{1}.bin"
+    .incbin "{2}{1}.elf"
 app_{0}_end:"#,
             idx, app, TARGET_PATH
         )?;

os/src/config.rs

@@ -3,18 +3,22 @@
 #[allow(unused)]
 
 /// user app's stack size
-pub const USER_STACK_SIZE: usize = 4096;
+pub const USER_STACK_SIZE: usize = 4096 * 2;
 /// kernel stack size
 pub const KERNEL_STACK_SIZE: usize = 4096 * 2;
 /// kernel heap size
-pub const KERNEL_HEAP_SIZE: usize = 0x20000;
-/// the max number of apps
-pub const MAX_APP_NUM: usize = 16;
-/// base_addr(changed) of app
-pub const APP_BASE_ADDRESS: usize = 0x80400000;
-/// size limit of app
-pub const APP_SIZE_LIMIT: usize = 0x20000;
+pub const KERNEL_HEAP_SIZE: usize = 0x200_0000;
 
+/// page size : 4KB
+pub const PAGE_SIZE: usize = 0x1000;
+/// page size bits: 12
+pub const PAGE_SIZE_BITS: usize = 0xc;
+/// the max number of syscall
+pub const MAX_SYSCALL_NUM: usize = 500;
+/// the virtual addr of trapoline
+pub const TRAMPOLINE: usize = usize::MAX - PAGE_SIZE + 1;
+/// the virtual addr of trap context
+pub const TRAP_CONTEXT_BASE: usize = TRAMPOLINE - PAGE_SIZE;
 /// clock frequency
 pub const CLOCK_FREQ: usize = 12500000;
 /// the physical memory end

os/src/linker.ld

@@ -10,6 +10,10 @@ SECTIONS
     stext = .;
     .text : {
         *(.text.entry)
+        . = ALIGN(4K);
+        strampoline = .;
+        *(.text.trampoline);
+        . = ALIGN(4K);
         *(.text .text.*)
     }
 
@@ -31,6 +35,7 @@ SECTIONS
 
     . = ALIGN(4K);
     edata = .;
+    sbss_with_stack = .;
     .bss : {
         *(.bss.stack)
         sbss = .;

os/src/loader.rs

@@ -1,57 +1,4 @@
 //! Loading user applications into memory
-//!
-//! For chapter 3, user applications are simply part of the data included in the
-//! kernel binary, so we only need to copy them to the space allocated for each
-//! app to load them. We also allocate fixed spaces for each task's
-//! [`KernelStack`] and [`UserStack`].
-
-use crate::config::*;
-use crate::trap::TrapContext;
-use core::arch::asm;
-
-#[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
-    }
-}
-
-/// Get base address of app i.
-fn get_base_i(app_id: usize) -> usize {
-    APP_BASE_ADDRESS + app_id * APP_SIZE_LIMIT
-}
 
 /// Get the total number of applications.
 pub fn get_num_app() -> usize {
@@ -61,43 +8,19 @@ pub fn get_num_app() -> usize {
     unsafe { (_num_app as usize as *const usize).read_volatile() }
 }
 
-/// Load nth user app at
-/// [APP_BASE_ADDRESS + n * APP_SIZE_LIMIT, APP_BASE_ADDRESS + (n+1) * APP_SIZE_LIMIT).
-pub fn load_apps() {
+/// get applications data
+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) };
-    // 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);
-    }
-    // Memory fence about fetching the instruction memory
-    // It is guaranteed that a subsequent instruction fetch must
-    // observes all previous writes to the instruction memory.
-    // Therefore, fence.i must be executed after we have loaded
-    // the code of the next app into the instruction memory.
-    // See also: riscv non-priv spec chapter 3, 'Zifencei' extension.
+    assert!(app_id < num_app);
     unsafe {
-        asm!("fence.i");
+        core::slice::from_raw_parts(
+            app_start[app_id] as *const u8,
+            app_start[app_id + 1] - app_start[app_id],
+        )
     }
 }
-
-/// get app info with entry and sp and save `TrapContext` in kernel stack
-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(),
-    ))
-}

os/src/main.rs

@@ -22,6 +22,8 @@
 #![feature(panic_info_message)]
 #![feature(alloc_error_handler)]
 
+#[macro_use]
+extern crate bitflags;
 #[macro_use]
 extern crate log;
 
@@ -30,10 +32,10 @@ extern crate alloc;
 #[macro_use]
 mod console;
 pub mod config;
-mod heap_alloc;
 pub mod lang_items;
 mod loader;
 pub mod logging;
+pub mod mm;
 pub mod sbi;
 pub mod sync;
 pub mod syscall;
@@ -97,9 +99,10 @@ fn kernel_log_info() {
 pub fn rust_main() -> ! {
     clear_bss();
     kernel_log_info();
-    heap_alloc::init_heap();
+    mm::init();
+    println!("[kernel] back to world!");
+    mm::remap_test();
     trap::init();
-    loader::load_apps();
     trap::enable_timer_interrupt();
     timer::set_next_trigger();
     task::run_first_task();