FFI-safe shared function table

Cargo.lock

@@ -95,6 +95,16 @@ version = "0.6.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b5eb417147ba9860a96cfe72a0b93bf88fee1744b5636ec99ab20c1aa9376581"
 
+[[package]]
+name = "riscv"
+version = "0.6.0"
+source = "git+https://github.com.cnpmjs.org/rust-embedded/riscv.git?rev=7e9d2e5b#7e9d2e5bb05ccabf5539fcea36877748d7236c6e"
+dependencies = [
+ "bare-metal",
+ "bit_field",
+ "riscv-target",
+]
+
 [[package]]
 name = "riscv"
 version = "0.6.0"
@@ -139,6 +149,17 @@ version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
 
+[[package]]
+name = "shared-scheduler"
+version = "0.1.0"
+dependencies = [
+ "buddy_system_allocator",
+ "lazy_static",
+ "r0",
+ "riscv 0.6.0 (git+https://github.com.cnpmjs.org/rust-embedded/riscv.git?rev=7e9d2e5b)",
+ "spin 0.7.1",
+]
+
 [[package]]
 name = "spin"
 version = "0.5.2"
@@ -170,7 +191,7 @@ dependencies = [
  "hashbrown",
  "lazy_static",
  "r0",
- "riscv",
+ "riscv 0.6.0 (git+https://github.com.cnpmjs.org/HUST-OS/riscv.git)",
  "spin 0.7.1",
  "woke",
 ]
@@ -181,6 +202,7 @@ version = "0.1.0"
 dependencies = [
  "buddy_system_allocator",
  "lazy_static",
+ "r0",
  "spin 0.5.2",
  "woke",
 ]

shared-scheduler/src/main.rs

@@ -1,5 +1,6 @@
-//! 为协程内核设计的共享调度器运行时
-//! 
+//! 为协程内核设计的共享调度器载荷
+//! 以二进制包的形式编译
+
 #![no_std]
 #![no_main]
 #![feature(panic_info_message)]
@@ -25,12 +26,12 @@ static HEAP: LockedHeap = LockedHeap::empty();
 
 #[cfg_attr(not(test), panic_handler)]
 pub fn panic_handler(panic_info: &core::panic::PanicInfo) -> ! {
-    println!("[shared-rt] panic: {:?}", panic_info);
+    println!("[shared scheduler] panic: {:?}", panic_info);
     sbi::shutdown()    
 }
 
 #[cfg_attr(not(test), alloc_error_handler)]
 pub fn handle_alloc_error(layout: core::alloc::Layout) -> ! {
-    println!("[shared-rt] alloc panic: {:?}", layout);
+    println!("[shared scheduler] alloc panic: {:?}", layout);
     sbi::shutdown()
 }

shared-scheduler/src/task/shared.rs

@@ -10,17 +10,15 @@ use spin::Mutex;
 #[no_mangle]
 #[link_section = ".data"]
 #[export_name = "_raw_table"]
-pub static __shared_raw_table: [unsafe extern "C" fn(); 3] = [
-    _shared_scheduler,
-    _shared_add_task,
-    _shared_pop_task    
-];
-
-extern "C" {
-    fn _shared_scheduler();
-    fn _shared_add_task();
-    fn _shared_pop_task();
-}
+pub static __shared_raw_table: (
+    extern "C" fn() -> NonNull<()>,
+    unsafe extern "C" fn(NonNull<()>, SharedTaskHandle) -> FfiOption<SharedTaskHandle>,
+    unsafe extern "C" fn(NonNull<()>, extern "C" fn(&SharedTaskHandle) -> bool) -> TaskResult,
+) = (
+    shared_scheduler,
+    shared_add_task,
+    shared_pop_task,    
+);
 
 /// 共享调度器的类型
 type SharedScheduler = Mutex<RingFifoScheduler<SharedTaskHandle, 100>>;
@@ -39,9 +37,8 @@ pub fn current_task() -> Option<SharedTaskHandle> {
 /// 得到共享的调度器指针
 /// 
 /// 可以在共享的添加任务，弹出下一个任务中使用
-#[no_mangle]
-#[export_name = "_shared_scheduler"]
-pub fn shared_scheduler() -> NonNull<()> {
+// todo：不要导出这个函数
+pub extern "C" fn shared_scheduler() -> NonNull<()> {
     NonNull::new(&SHARED_SCHEDULER as *const _ as *mut ())
         .expect("create non null pointer")
 }
@@ -59,28 +56,41 @@ pub struct SharedTaskHandle {
     pub(crate) task_ptr: usize,
 }
 
+// 跨FFI边界安全的Option枚举结构
+#[repr(C)]
+pub enum FfiOption<T> {
+    None,
+    Some(T),
+}
+
+impl<T> From<Option<T>> for FfiOption<T> {
+    fn from(src: Option<T>) -> FfiOption<T> {
+        if let Some(t) = src {
+            FfiOption::Some(t)
+        } else {
+            FfiOption::None
+        }
+    }
+}
+
 /// 给共享调度器添加任务
 /// 
 /// 在内核态和用户态都可以调用
-#[no_mangle]
-#[export_name = "_shared_add_task"]
-pub unsafe fn shared_add_task(
+pub unsafe extern "C" fn shared_add_task(
     shared_scheduler: NonNull<()>,
     handle: SharedTaskHandle
-) -> Option<SharedTaskHandle> {
+) -> FfiOption<SharedTaskHandle> { // 如果未来有FFI-safe core::option::Option，换掉这个返回值
     let s: NonNull<SharedScheduler> = shared_scheduler.cast();
     let mut scheduler = s.as_ref().lock();
-    scheduler.add_task(handle)
+    scheduler.add_task(handle).into()
 }
 
 /// 从共享调度器中弹出一个任务
 /// 
 /// 在内核态和用户态都可以调用
-#[no_mangle]
-#[export_name = "_shared_pop_task"]
-pub unsafe fn shared_pop_task(
+pub unsafe extern "C" fn shared_pop_task(
     shared_scheduler: NonNull<()>,
-    should_switch: fn(&SharedTaskHandle) -> bool
+    should_switch: extern "C" fn(&SharedTaskHandle) -> bool
 ) -> TaskResult {
     // 得到共享调度器的引用
     let mut s: NonNull<SharedScheduler> = shared_scheduler.cast();
@@ -98,4 +108,4 @@ pub unsafe fn shared_pop_task(
         // 没有任务了，返回已完成
         return TaskResult::Finished;
     }
-}
+}

tornado-kernel/src/memory/mapping/memory_set.rs

@@ -119,7 +119,7 @@ impl MemorySet {
             mapping.map_segment(segment, None)?;
         }
 
-        // 映射共享负荷，目前地址是写死的
+        // 映射共享载荷，目前地址是写死的
         let va_range = VirtualAddress(0x8600_0000)..VirtualAddress(0x8640_0000);
         let pa_range = PhysicalAddress(0x8600_0000)..PhysicalAddress(0x8640_0000);
         mapping.map_defined(&va_range, &pa_range, Flags::WRITABLE | Flags::READABLE | Flags::EXECUTABLE );