重构系统调用模块 (#267)

* 完成系统调用模块重构

* 更新github workflow

kernel/src/arch/x86_64/cpu.rs

@@ -15,3 +15,10 @@ pub fn cpu_relax() {
         asm!("pause");
     }
 }
+
+/// 重置cpu
+pub fn cpu_reset() -> ! {
+    // 重启计算机
+    unsafe { x86::io::outb(0x64, 0xfe) };
+    loop {}
+}

kernel/src/arch/x86_64/mod.rs

@@ -8,5 +8,6 @@ pub mod mm;
 pub mod pci;
 pub mod rand;
 pub mod sched;
+pub mod syscall;
 
 pub use interrupt::X86_64InterruptArch as CurrentIrqArch;

kernel/src/arch/x86_64/syscall.rs

@@ -0,0 +1,113 @@
+use core::ffi::c_void;
+
+use crate::{
+    include::bindings::bindings::{
+        pt_regs, set_system_trap_gate, verify_area, CLONE_FS, CLONE_SIGNAL, CLONE_VM, PAGE_4K_SIZE,
+    },
+    ipc::signal::sys_rt_sigreturn,
+    kinfo,
+    syscall::{Syscall, SystemError, SYS_EXECVE, SYS_FORK, SYS_RT_SIGRETURN, SYS_VFORK},
+};
+
+use super::{
+    asm::{ptrace::user_mode},
+    mm::barrier::mfence,
+};
+
+extern "C" {
+    fn do_fork(regs: *mut pt_regs, clone_flags: u64, stack_start: u64, stack_size: u64) -> u64;
+    fn c_sys_execve(
+        path: *const u8,
+        argv: *const *const u8,
+        envp: *const *const u8,
+        regs: &mut pt_regs,
+    ) -> u64;
+
+    fn syscall_int();
+}
+
+macro_rules! syscall_return {
+    ($val:expr, $regs:expr) => {{
+        let ret = $val;
+        $regs.rax = ret as u64;
+        return;
+    }};
+}
+
+#[no_mangle]
+pub extern "C" fn syscall_handler(regs: &mut pt_regs) -> () {
+    let syscall_num = regs.rax as usize;
+    let args = [
+        regs.r8 as usize,
+        regs.r9 as usize,
+        regs.r10 as usize,
+        regs.r11 as usize,
+        regs.r12 as usize,
+        regs.r13 as usize,
+        regs.r14 as usize,
+        regs.r15 as usize,
+    ];
+    mfence();
+    mfence();
+    let from_user = user_mode(regs);
+
+    // 由于进程管理未完成重构，有些系统调用需要在这里临时处理，以后这里的特殊处理要删掉。
+    match syscall_num {
+        SYS_FORK => unsafe {
+            syscall_return!(do_fork(regs, 0, regs.rsp, 0), regs);
+        },
+        SYS_VFORK => unsafe {
+            syscall_return!(
+                do_fork(
+                    regs,
+                    (CLONE_VM | CLONE_FS | CLONE_SIGNAL) as u64,
+                    regs.rsp,
+                    0,
+                ),
+                regs
+            );
+        },
+        SYS_EXECVE => {
+            let path_ptr = args[0];
+            let argv_ptr = args[1];
+            let env_ptr = args[2];
+
+            // 权限校验
+            if from_user
+                && (unsafe { !verify_area(path_ptr as u64, PAGE_4K_SIZE as u64) }
+                    || unsafe { !verify_area(argv_ptr as u64, PAGE_4K_SIZE as u64) })
+                || unsafe { !verify_area(env_ptr as u64, PAGE_4K_SIZE as u64) }
+            {
+                syscall_return!(SystemError::EFAULT.to_posix_errno() as u64, regs);
+            } else {
+                syscall_return!(
+                    unsafe {
+                        c_sys_execve(
+                            path_ptr as *const u8,
+                            argv_ptr as *const *const u8,
+                            env_ptr as *const *const u8,
+                            regs,
+                        )
+                    },
+                    regs
+                );
+            }
+        }
+
+        SYS_RT_SIGRETURN => {
+            syscall_return!(sys_rt_sigreturn(regs), regs);
+        }
+        // SYS_SCHED => {
+        //     syscall_return!(sched(from_user) as u64, regs);
+        // }
+        _ => {}
+    }
+    syscall_return!(Syscall::handle(syscall_num, &args, from_user) as u64, regs);
+}
+
+/// 系统调用初始化
+pub fn arch_syscall_init() -> Result<(), SystemError> {
+    kinfo!("arch_syscall_init\n");
+    unsafe { set_system_trap_gate(0x80, 0, syscall_int as *mut c_void) }; // 系统调用门
+    return Ok(());
+}