1 use core::ffi::c_void; 2 3 use crate::{ 4 arch::{ 5 ipc::signal::X86_64SignalArch, 6 syscall::nr::{SYS_ARCH_PRCTL, SYS_RT_SIGRETURN}, 7 CurrentIrqArch, 8 }, 9 exception::InterruptArch, 10 include::bindings::bindings::set_system_trap_gate, 11 ipc::signal_types::SignalArch, 12 libs::align::SafeForZero, 13 mm::VirtAddr, 14 process::ProcessManager, 15 syscall::{Syscall, SYS_SCHED}, 16 }; 17 use alloc::string::String; 18 use system_error::SystemError; 19 20 use super::{interrupt::TrapFrame, mm::barrier::mfence}; 21 22 pub mod nr; 23 24 /// ### 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 25 /// 26 /// 在syscall指令中将会从该结构体中读取系统调用栈和暂存rsp, 27 /// 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 28 #[repr(C)] 29 #[derive(Debug, Clone)] 30 pub(super) struct X86_64GSData { 31 pub(super) kaddr: VirtAddr, 32 pub(super) uaddr: VirtAddr, 33 } 34 35 impl X86_64GSData { 36 /// ### 设置系统调用栈，将会在下一个调度后写入KernelGsbase 37 pub fn set_kstack(&mut self, kstack: VirtAddr) { 38 self.kaddr = kstack; 39 } 40 } 41 42 unsafe impl SafeForZero for X86_64GSData {} 43 44 extern "C" { 45 fn syscall_int(); 46 fn syscall_64(); 47 } 48 49 macro_rules! syscall_return { 50 ($val:expr, $regs:expr, $show:expr) => {{ 51 let ret = $val; 52 $regs.rax = ret as u64; 53 54 if $show { 55 let pid = ProcessManager::current_pcb().pid(); 56 crate::kdebug!("syscall return:pid={:?},ret= {:?}\n", pid, ret as isize); 57 } 58 59 unsafe { 60 CurrentIrqArch::interrupt_disable(); 61 } 62 return; 63 }}; 64 } 65 66 #[no_mangle] 67 pub extern "sysv64" fn syscall_handler(frame: &mut TrapFrame) -> () { 68 let syscall_num = frame.rax as usize; 69 // 防止sys_sched由于超时无法退出导致的死锁 70 if syscall_num != SYS_SCHED { 71 unsafe { 72 CurrentIrqArch::interrupt_enable(); 73 } 74 } 75 76 let args = [ 77 frame.rdi as usize, 78 frame.rsi as usize, 79 frame.rdx as usize, 80 frame.r10 as usize, 81 frame.r8 as usize, 82 frame.r9 as usize, 83 ]; 84 mfence(); 85 let pid = ProcessManager::current_pcb().pid(); 86 let show = false; 87 // let show = if syscall_num != SYS_SCHED && pid.data() > 3 { 88 // true 89 // } else { 90 // false 91 // }; 92 93 if show { 94 crate::kdebug!("syscall: pid: {:?}, num={:?}\n", pid, syscall_num); 95 } 96 97 // Arch specific syscall 98 match syscall_num { 99 SYS_RT_SIGRETURN => { 100 syscall_return!( 101 X86_64SignalArch::sys_rt_sigreturn(frame) as usize, 102 frame, 103 show 104 ); 105 } 106 SYS_ARCH_PRCTL => { 107 syscall_return!( 108 Syscall::arch_prctl(args[0], args[1]) 109 .unwrap_or_else(|e| e.to_posix_errno() as usize), 110 frame, 111 show 112 ); 113 } 114 _ => {} 115 } 116 syscall_return!( 117 Syscall::handle(syscall_num, &args, frame).unwrap_or_else(|e| e.to_posix_errno() as usize) 118 as u64, 119 frame, 120 show 121 ); 122 } 123 124 /// 系统调用初始化 125 pub fn arch_syscall_init() -> Result<(), SystemError> { 126 // kinfo!("arch_syscall_init\n"); 127 unsafe { set_system_trap_gate(0x80, 0, syscall_int as *mut c_void) }; // 系统调用门 128 unsafe { init_syscall_64() }; 129 return Ok(()); 130 } 131 132 /// 执行第一个用户进程的函数（只应该被调用一次） 133 /// 134 /// 当进程管理重构完成后，这个函数应该被删除。调整为别的函数。 135 #[no_mangle] 136 pub extern "C" fn rs_exec_init_process(frame: &mut TrapFrame) -> usize { 137 let path = String::from("/bin/shell.elf"); 138 let argv = vec![String::from("/bin/shell.elf")]; 139 let envp = vec![String::from("PATH=/bin")]; 140 let r = Syscall::do_execve(path, argv, envp, frame); 141 // kdebug!("rs_exec_init_process: r: {:?}\n", r); 142 return r.map(|_| 0).unwrap_or_else(|e| e.to_posix_errno() as usize); 143 } 144 145 /// syscall指令初始化函数 146 pub(super) unsafe fn init_syscall_64() { 147 let mut efer = x86::msr::rdmsr(x86::msr::IA32_EFER); 148 efer |= 0x1; 149 x86::msr::wrmsr(x86::msr::IA32_EFER, efer); 150 151 let syscall_base = (1 as u16) << 3; 152 let sysret_base = ((4 as u16) << 3) | 3; 153 let high = (u32::from(sysret_base) << 16) | u32::from(syscall_base); 154 // 初始化STAR寄存器 155 x86::msr::wrmsr(x86::msr::IA32_STAR, u64::from(high) << 32); 156 157 // 初始化LSTAR,该寄存器存储syscall指令入口 158 x86::msr::wrmsr(x86::msr::IA32_LSTAR, syscall_64 as u64); 159 x86::msr::wrmsr(x86::msr::IA32_FMASK, 0xfffffffe); 160 } 161