riscv64: switch process

kernel/Cargo.toml

@@ -62,7 +62,7 @@ x86_64 = "=0.14.10"
 
 # target为riscv64时，使用下面的依赖
 [target.'cfg(target_arch = "riscv64")'.dependencies]
-riscv = { git = "https://git.mirrors.dragonos.org.cn/DragonOS-Community/riscv.git", revision = "79d27d0f3a", features = [ "s-mode" ] }
+riscv = { git = "https://git.mirrors.dragonos.org.cn/DragonOS-Community/riscv.git", revision = "01fc40d", features = [ "s-mode" ] }
 sbi-rt = { version = "=0.0.3", features = ["legacy"] }
 
 

kernel/src/arch/riscv64/cpu.rs

@@ -53,7 +53,7 @@ pub(super) fn local_context() -> &'static PerCpuVar<LocalContext> {
 ///
 /// - 从用户态进入内核态时，会从sscratch寄存器加载这个结构体的地址到tp寄存器，并把sscratch寄存器清零
 /// - 从内核态进入用户态时，会将tp寄存器的值保存到sscratch寄存器
-#[derive(Debug)]
+#[derive(Debug, Clone, Copy)]
 pub(super) struct LocalContext {
     /// 当前cpu的id
     pub current_cpu: ProcessorId,
@@ -64,7 +64,7 @@ pub(super) struct LocalContext {
 }
 
 impl LocalContext {
-    fn new(cpu: ProcessorId) -> Self {
+    pub fn new(cpu: ProcessorId) -> Self {
         Self {
             current_cpu: cpu,
             kernel_sp: 0,
@@ -102,6 +102,13 @@ impl LocalContext {
         // 写入tp寄存器
         riscv::register::tp::write(ptr);
     }
+
+    pub fn restore(&mut self, from: &LocalContext) {
+        // 不恢复cpu id
+
+        self.kernel_sp = from.kernel_sp;
+        self.user_sp = from.user_sp;
+    }
 }
 
 /// 初始化本地上下文

kernel/src/arch/riscv64/interrupt/mod.rs

@@ -61,44 +61,44 @@ impl InterruptArch for RiscV64InterruptArch {
 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct TrapFrame {
-    epc: usize,
-    ra: usize,
-    sp: usize,
-    gp: usize,
-    tp: usize,
-    t0: usize,
-    t1: usize,
-    t2: usize,
-    s0: usize,
-    s1: usize,
-    a0: usize,
-    a1: usize,
-    a2: usize,
-    a3: usize,
-    a4: usize,
-    a5: usize,
-    a6: usize,
-    a7: usize,
-    s2: usize,
-    s3: usize,
-    s4: usize,
-    s5: usize,
-    s6: usize,
-    s7: usize,
-    s8: usize,
-    s9: usize,
-    s10: usize,
-    s11: usize,
-    t3: usize,
-    t4: usize,
-    t5: usize,
-    t6: usize,
+    pub epc: usize,
+    pub ra: usize,
+    pub sp: usize,
+    pub gp: usize,
+    pub tp: usize,
+    pub t0: usize,
+    pub t1: usize,
+    pub t2: usize,
+    pub s0: usize,
+    pub s1: usize,
+    pub a0: usize,
+    pub a1: usize,
+    pub a2: usize,
+    pub a3: usize,
+    pub a4: usize,
+    pub a5: usize,
+    pub a6: usize,
+    pub a7: usize,
+    pub s2: usize,
+    pub s3: usize,
+    pub s4: usize,
+    pub s5: usize,
+    pub s6: usize,
+    pub s7: usize,
+    pub s8: usize,
+    pub s9: usize,
+    pub s10: usize,
+    pub s11: usize,
+    pub t3: usize,
+    pub t4: usize,
+    pub t5: usize,
+    pub t6: usize,
     // 以下是中断发生时自动保存的寄存器
-    status: Sstatus,
-    badaddr: usize,
-    cause: Scause,
+    pub status: Sstatus,
+    pub badaddr: usize,
+    pub cause: Scause,
     /// a0 value before the syscall
-    origin_a0: usize,
+    pub origin_a0: usize,
 }
 
 impl TrapFrame {