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+
mod context;
+
+use crate::syscall::syscall;
+use crate::task::{exit_current_and_run_next, suspend_current_and_run_next};
+use crate::timer::set_next_trigger;
+use core::arch::global_asm;
+use riscv::register::{
+ mtvec::TrapMode,
+ scause::{self, Exception, Interrupt, Trap},
+ sie, stval, stvec,
+};
+
+global_asm!(include_str!("trap.S"));
+
+
+pub fn init() {
+ extern "C" {
+ fn __alltraps();
+ }
+ unsafe {
+ stvec::write(__alltraps as usize, TrapMode::Direct);
+ }
+}
+
+
+pub fn enable_timer_interrupt() {
+ unsafe {
+ sie::set_stimer();
+ }
+}
+
+#[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) => {
+ println!("[kernel] PageFault in application, bad addr = {:#x}, bad instruction = {:#x}, kernel killed it.", stval, cx.sepc);
+ exit_current_and_run_next();
+ }
+ Trap::Exception(Exception::IllegalInstruction) => {
+ println!("[kernel] IllegalInstruction in application, kernel killed it.");
+ exit_current_and_run_next();
+ }
+ Trap::Interrupt(Interrupt::SupervisorTimer) => {
+ set_next_trigger();
+ suspend_current_and_run_next();
+ }
+ _ => {
+ panic!(
+ "Unsupported trap {:?}, stval = {:#x}!",
+ scause.cause(),
+ stval
+ );
+ }
+ }
+ cx
+}
+
+pub use context::TrapContext;
+
