use crate::{ arch::{ ipc::signal::X86_64SignalArch, syscall::nr::{SYS_ARCH_PRCTL, SYS_RT_SIGRETURN}, CurrentIrqArch, }, exception::InterruptArch, ipc::signal_types::SignalArch, libs::align::SafeForZero, mm::VirtAddr, process::ProcessManager, syscall::{Syscall, SYS_SCHED}, }; use system_error::SystemError; use super::{ interrupt::{entry::set_system_trap_gate, TrapFrame}, mm::barrier::mfence, }; pub mod nr; /// ### 存储PCB系统调用栈以及在syscall过程中暂存用户态rsp的结构体 /// /// 在syscall指令中将会从该结构体中读取系统调用栈和暂存rsp, /// 使用`gsbase`寄存器实现,后续如果需要使用gsbase寄存器,需要相应设置正确的偏移量 #[repr(C)] #[derive(Debug, Clone)] pub(super) struct X86_64GSData { pub(super) kaddr: VirtAddr, pub(super) uaddr: VirtAddr, } impl X86_64GSData { /// ### 设置系统调用栈,将会在下一个调度后写入KernelGsbase pub fn set_kstack(&mut self, kstack: VirtAddr) { self.kaddr = kstack; } } unsafe impl SafeForZero for X86_64GSData {} extern "C" { fn syscall_int(); fn syscall_64(); } macro_rules! syscall_return { ($val:expr, $regs:expr, $show:expr) => {{ let ret = $val; $regs.rax = ret as u64; if $show { let pid = ProcessManager::current_pcb().pid(); crate::kdebug!("syscall return:pid={:?},ret= {:?}\n", pid, ret as isize); } unsafe { CurrentIrqArch::interrupt_disable(); } return; }}; } #[no_mangle] pub extern "sysv64" fn syscall_handler(frame: &mut TrapFrame) { let syscall_num = frame.rax as usize; // 防止sys_sched由于超时无法退出导致的死锁 if syscall_num == SYS_SCHED { unsafe { CurrentIrqArch::interrupt_disable(); } } else { unsafe { CurrentIrqArch::interrupt_enable(); } } let args = [ frame.rdi as usize, frame.rsi as usize, frame.rdx as usize, frame.r10 as usize, frame.r8 as usize, frame.r9 as usize, ]; mfence(); let pid = ProcessManager::current_pcb().pid(); let show = false; // let show = if syscall_num != SYS_SCHED && pid.data() >= 7 { // true // } else { // false // }; if show { crate::kdebug!("syscall: pid: {:?}, num={:?}\n", pid, syscall_num); } // Arch specific syscall match syscall_num { SYS_RT_SIGRETURN => { syscall_return!( X86_64SignalArch::sys_rt_sigreturn(frame) as usize, frame, show ); } SYS_ARCH_PRCTL => { syscall_return!( Syscall::arch_prctl(args[0], args[1]) .unwrap_or_else(|e| e.to_posix_errno() as usize), frame, show ); } _ => {} } syscall_return!( Syscall::handle(syscall_num, &args, frame).unwrap_or_else(|e| e.to_posix_errno() as usize) as u64, frame, show ); } /// 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, VirtAddr::new(syscall_int as usize)) }; // 系统调用门 unsafe { init_syscall_64() }; return Ok(()); } /// syscall指令初始化函数 pub(super) unsafe fn init_syscall_64() { let mut efer = x86::msr::rdmsr(x86::msr::IA32_EFER); efer |= 0x1; x86::msr::wrmsr(x86::msr::IA32_EFER, efer); let syscall_base = (1_u16) << 3; let sysret_base = ((4_u16) << 3) | 3; let high = (u32::from(sysret_base) << 16) | u32::from(syscall_base); // 初始化STAR寄存器 x86::msr::wrmsr(x86::msr::IA32_STAR, u64::from(high) << 32); // 初始化LSTAR,该寄存器存储syscall指令入口 x86::msr::wrmsr(x86::msr::IA32_LSTAR, syscall_64 as usize as u64); x86::msr::wrmsr(x86::msr::IA32_FMASK, 0xfffffffe); }