xref: /DragonOS/kernel/src/syscall/mod.rs (revision a381e482cbe742b2e4bbeaacae134a8131bf3f91)
1 use core::{
2     ffi::{c_char, c_int, c_void, CStr},
3     sync::atomic::{AtomicBool, Ordering},
4 };
5 
6 use crate::{
7     arch::{ipc::signal::SigSet, syscall::nr::*},
8     driver::base::device::device_number::DeviceNumber,
9     libs::{futex::constant::FutexFlag, rand::GRandFlags},
10     process::{
11         fork::KernelCloneArgs,
12         resource::{RLimit64, RUsage},
13     },
14 };
15 
16 use num_traits::FromPrimitive;
17 use system_error::SystemError;
18 
19 use crate::{
20     arch::{cpu::cpu_reset, interrupt::TrapFrame, MMArch},
21     driver::base::block::SeekFrom,
22     filesystem::vfs::{
23         fcntl::FcntlCommand,
24         file::FileMode,
25         syscall::{ModeType, PosixKstat, SEEK_CUR, SEEK_END, SEEK_MAX, SEEK_SET},
26         MAX_PATHLEN,
27     },
28     include::bindings::bindings::{PAGE_2M_SIZE, PAGE_4K_SIZE},
29     kinfo,
30     libs::align::page_align_up,
31     mm::{verify_area, MemoryManagementArch, VirtAddr},
32     net::syscall::SockAddr,
33     process::{fork::CloneFlags, Pid},
34     time::{
35         syscall::{PosixTimeZone, PosixTimeval},
36         TimeSpec,
37     },
38 };
39 
40 use self::{
41     misc::SysInfo,
42     user_access::{UserBufferReader, UserBufferWriter},
43 };
44 
45 pub mod misc;
46 pub mod user_access;
47 
48 // 与linux不一致的调用,在linux基础上累加
49 pub const SYS_PUT_STRING: usize = 100000;
50 pub const SYS_SBRK: usize = 100001;
51 /// todo: 该系统调用与Linux不一致,将来需要删除该系统调用!!! 删的时候记得改C版本的libc
52 pub const SYS_CLOCK: usize = 100002;
53 pub const SYS_SCHED: usize = 100003;
54 
55 #[derive(Debug)]
56 pub struct Syscall;
57 
58 extern "C" {
59     fn do_put_string(s: *const u8, front_color: u32, back_color: u32) -> usize;
60 }
61 
62 #[no_mangle]
63 pub extern "C" fn syscall_init() -> i32 {
64     kinfo!("Initializing syscall...");
65     Syscall::init().expect("syscall init failed");
66     kinfo!("Syscall init successfully!");
67     return 0;
68 }
69 
70 impl Syscall {
71     /// 初始化系统调用
72     pub fn init() -> Result<(), SystemError> {
73         static INIT_FLAG: AtomicBool = AtomicBool::new(false);
74         let prev = INIT_FLAG.swap(true, Ordering::SeqCst);
75         if prev {
76             panic!("Cannot initialize syscall more than once!");
77         }
78         return crate::arch::syscall::arch_syscall_init();
79     }
80     /// @brief 系统调用分发器,用于分发系统调用。
81     ///
82     /// 这个函数内,需要根据系统调用号,调用对应的系统调用处理函数。
83     /// 并且,对于用户态传入的指针参数,需要在本函数内进行越界检查,防止访问到内核空间。
84     #[inline(never)]
85     pub fn handle(
86         syscall_num: usize,
87         args: &[usize],
88         frame: &mut TrapFrame,
89     ) -> Result<usize, SystemError> {
90         let r = match syscall_num {
91             SYS_PUT_STRING => {
92                 Self::put_string(args[0] as *const u8, args[1] as u32, args[2] as u32)
93             }
94             #[cfg(target_arch = "x86_64")]
95             SYS_OPEN => {
96                 let path: &CStr = unsafe { CStr::from_ptr(args[0] as *const c_char) };
97                 let path: Result<&str, core::str::Utf8Error> = path.to_str();
98                 let res = if path.is_err() {
99                     Err(SystemError::EINVAL)
100                 } else {
101                     let path: &str = path.unwrap();
102 
103                     let flags = args[1];
104                     let mode = args[2];
105 
106                     let open_flags: FileMode = FileMode::from_bits_truncate(flags as u32);
107                     let mode = ModeType::from_bits(mode as u32).ok_or(SystemError::EINVAL)?;
108                     Self::open(path, open_flags, mode, true)
109                 };
110                 res
111             }
112 
113             SYS_OPENAT => {
114                 let dirfd = args[0] as i32;
115                 let path: &CStr = unsafe { CStr::from_ptr(args[1] as *const c_char) };
116                 let flags = args[2];
117                 let mode = args[3];
118 
119                 let path: Result<&str, core::str::Utf8Error> = path.to_str();
120                 let res = if path.is_err() {
121                     Err(SystemError::EINVAL)
122                 } else {
123                     let path: &str = path.unwrap();
124 
125                     let open_flags: FileMode =
126                         FileMode::from_bits(flags as u32).ok_or(SystemError::EINVAL)?;
127                     let mode = ModeType::from_bits(mode as u32).ok_or(SystemError::EINVAL)?;
128                     Self::openat(dirfd, path, open_flags, mode, true)
129                 };
130                 res
131             }
132             SYS_CLOSE => {
133                 let fd = args[0];
134 
135                 let res = Self::close(fd);
136 
137                 res
138             }
139             SYS_READ => {
140                 let fd = args[0] as i32;
141                 let buf_vaddr = args[1];
142                 let len = args[2];
143                 let from_user = frame.from_user();
144                 let mut user_buffer_writer =
145                     UserBufferWriter::new(buf_vaddr as *mut u8, len, from_user)?;
146 
147                 let user_buf = user_buffer_writer.buffer(0)?;
148                 let res = Self::read(fd, user_buf);
149                 res
150             }
151             SYS_WRITE => {
152                 let fd = args[0] as i32;
153                 let buf_vaddr = args[1];
154                 let len = args[2];
155                 let from_user = frame.from_user();
156                 let user_buffer_reader =
157                     UserBufferReader::new(buf_vaddr as *const u8, len, from_user)?;
158 
159                 let user_buf = user_buffer_reader.read_from_user(0)?;
160                 let res = Self::write(fd, user_buf);
161                 res
162             }
163 
164             SYS_LSEEK => {
165                 let fd = args[0] as i32;
166                 let offset = args[1] as i64;
167                 let whence = args[2] as u32;
168 
169                 let w = match whence {
170                     SEEK_SET => Ok(SeekFrom::SeekSet(offset)),
171                     SEEK_CUR => Ok(SeekFrom::SeekCurrent(offset)),
172                     SEEK_END => Ok(SeekFrom::SeekEnd(offset)),
173                     SEEK_MAX => Ok(SeekFrom::SeekEnd(0)),
174                     _ => Err(SystemError::EINVAL),
175                 }?;
176 
177                 Self::lseek(fd, w)
178             }
179             SYS_IOCTL => {
180                 let fd = args[0];
181                 let cmd = args[1];
182                 let data = args[2];
183                 Self::ioctl(fd, cmd as u32, data)
184             }
185 
186             #[cfg(target_arch = "x86_64")]
187             SYS_FORK => Self::fork(frame),
188             #[cfg(target_arch = "x86_64")]
189             SYS_VFORK => Self::vfork(frame),
190 
191             SYS_BRK => {
192                 let new_brk = VirtAddr::new(args[0]);
193                 Self::brk(new_brk).map(|vaddr| vaddr.data())
194             }
195 
196             SYS_SBRK => {
197                 let increment = args[0] as isize;
198                 Self::sbrk(increment).map(|vaddr: VirtAddr| vaddr.data())
199             }
200 
201             SYS_REBOOT => Self::reboot(),
202 
203             SYS_CHDIR => {
204                 // Closure for checking arguments
205                 let chdir_check = |arg0: usize| {
206                     if arg0 == 0 {
207                         return Err(SystemError::EFAULT);
208                     }
209                     let path_ptr = arg0 as *const c_char;
210                     let virt_addr = VirtAddr::new(path_ptr as usize);
211                     // 权限校验
212                     if path_ptr.is_null()
213                         || (frame.from_user()
214                             && verify_area(virt_addr, PAGE_2M_SIZE as usize).is_err())
215                     {
216                         return Err(SystemError::EINVAL);
217                     }
218                     let dest_path: &CStr = unsafe { CStr::from_ptr(path_ptr) };
219                     let dest_path: &str = dest_path.to_str().map_err(|_| SystemError::EINVAL)?;
220                     if dest_path.len() == 0 {
221                         return Err(SystemError::EINVAL);
222                     } else if dest_path.len() > MAX_PATHLEN as usize {
223                         return Err(SystemError::ENAMETOOLONG);
224                     }
225 
226                     return Ok(dest_path);
227                 };
228 
229                 let r = chdir_check(args[0])?;
230                 Self::chdir(r)
231             }
232 
233             #[allow(unreachable_patterns)]
234             SYS_GETDENTS64 | SYS_GETDENTS => {
235                 let fd = args[0] as i32;
236 
237                 let buf_vaddr = args[1];
238                 let len = args[2];
239                 let virt_addr: VirtAddr = VirtAddr::new(buf_vaddr);
240                 // 判断缓冲区是否来自用户态,进行权限校验
241                 let res = if frame.from_user() && verify_area(virt_addr, len as usize).is_err() {
242                     // 来自用户态,而buffer在内核态,这样的操作不被允许
243                     Err(SystemError::EPERM)
244                 } else if buf_vaddr == 0 {
245                     Err(SystemError::EFAULT)
246                 } else {
247                     let buf: &mut [u8] = unsafe {
248                         core::slice::from_raw_parts_mut::<'static, u8>(buf_vaddr as *mut u8, len)
249                     };
250                     Self::getdents(fd, buf)
251                 };
252 
253                 res
254             }
255 
256             SYS_EXECVE => {
257                 let path_ptr = args[0];
258                 let argv_ptr = args[1];
259                 let env_ptr = args[2];
260                 let virt_path_ptr = VirtAddr::new(path_ptr);
261                 let virt_argv_ptr = VirtAddr::new(argv_ptr);
262                 let virt_env_ptr = VirtAddr::new(env_ptr);
263                 // 权限校验
264                 if frame.from_user()
265                     && (verify_area(virt_path_ptr, MAX_PATHLEN as usize).is_err()
266                         || verify_area(virt_argv_ptr, PAGE_4K_SIZE as usize).is_err())
267                     || verify_area(virt_env_ptr, PAGE_4K_SIZE as usize).is_err()
268                 {
269                     Err(SystemError::EFAULT)
270                 } else {
271                     Self::execve(
272                         path_ptr as *const u8,
273                         argv_ptr as *const *const u8,
274                         env_ptr as *const *const u8,
275                         frame,
276                     )
277                     .map(|_| 0)
278                 }
279             }
280             SYS_WAIT4 => {
281                 let pid = args[0] as i32;
282                 let wstatus = args[1] as *mut i32;
283                 let options = args[2] as c_int;
284                 let rusage = args[3] as *mut c_void;
285                 // 权限校验
286                 // todo: 引入rusage之后,更正以下权限校验代码中,rusage的大小
287                 Self::wait4(pid.into(), wstatus, options, rusage)
288             }
289 
290             SYS_EXIT => {
291                 let exit_code = args[0];
292                 Self::exit(exit_code)
293             }
294             #[cfg(target_arch = "x86_64")]
295             SYS_MKDIR => {
296                 let path_ptr = args[0] as *const c_char;
297                 let mode = args[1];
298                 let virt_path_ptr = VirtAddr::new(path_ptr as usize);
299                 let security_check = || {
300                     if path_ptr.is_null()
301                         || (frame.from_user()
302                             && verify_area(virt_path_ptr, PAGE_2M_SIZE as usize).is_err())
303                     {
304                         return Err(SystemError::EINVAL);
305                     }
306                     let path: &CStr = unsafe { CStr::from_ptr(path_ptr) };
307                     let path: &str = path.to_str().map_err(|_| SystemError::EINVAL)?.trim();
308 
309                     if path == "" {
310                         return Err(SystemError::EINVAL);
311                     }
312                     return Ok(path);
313                 };
314 
315                 let path = security_check();
316                 if path.is_err() {
317                     Err(path.unwrap_err())
318                 } else {
319                     Self::mkdir(path.unwrap(), mode)
320                 }
321             }
322 
323             SYS_NANOSLEEP => {
324                 let req = args[0] as *const TimeSpec;
325                 let rem = args[1] as *mut TimeSpec;
326                 let virt_req = VirtAddr::new(req as usize);
327                 let virt_rem = VirtAddr::new(rem as usize);
328                 if frame.from_user()
329                     && (verify_area(virt_req, core::mem::size_of::<TimeSpec>() as usize).is_err()
330                         || verify_area(virt_rem, core::mem::size_of::<TimeSpec>() as usize)
331                             .is_err())
332                 {
333                     Err(SystemError::EFAULT)
334                 } else {
335                     Self::nanosleep(req, rem)
336                 }
337             }
338 
339             SYS_CLOCK => Self::clock(),
340             #[cfg(target_arch = "x86_64")]
341             SYS_PIPE => {
342                 let pipefd: *mut i32 = args[0] as *mut c_int;
343                 if pipefd.is_null() {
344                     Err(SystemError::EFAULT)
345                 } else {
346                     Self::pipe2(pipefd, FileMode::empty())
347                 }
348             }
349             SYS_PIPE2 => {
350                 let pipefd: *mut i32 = args[0] as *mut c_int;
351                 let arg1 = args[1];
352                 if pipefd.is_null() {
353                     Err(SystemError::EFAULT)
354                 } else {
355                     let flags = FileMode::from_bits_truncate(arg1 as u32);
356                     Self::pipe2(pipefd, flags)
357                 }
358             }
359 
360             SYS_UNLINKAT => {
361                 let dirfd = args[0] as i32;
362                 let pathname = args[1] as *const c_char;
363                 let flags = args[2] as u32;
364                 let virt_pathname = VirtAddr::new(pathname as usize);
365                 if frame.from_user() && verify_area(virt_pathname, PAGE_4K_SIZE as usize).is_err() {
366                     Err(SystemError::EFAULT)
367                 } else if pathname.is_null() {
368                     Err(SystemError::EFAULT)
369                 } else {
370                     let get_path = || {
371                         let pathname: &CStr = unsafe { CStr::from_ptr(pathname) };
372 
373                         let pathname: &str = pathname.to_str().map_err(|_| SystemError::EINVAL)?;
374                         if pathname.len() >= MAX_PATHLEN {
375                             return Err(SystemError::ENAMETOOLONG);
376                         }
377                         return Ok(pathname.trim());
378                     };
379                     let pathname = get_path();
380                     if pathname.is_err() {
381                         Err(pathname.unwrap_err())
382                     } else {
383                         // kdebug!("sys unlinkat: dirfd: {}, pathname: {}", dirfd, pathname.as_ref().unwrap());
384                         Self::unlinkat(dirfd, pathname.unwrap(), flags)
385                     }
386                 }
387             }
388 
389             #[cfg(target_arch = "x86_64")]
390             SYS_UNLINK => {
391                 let pathname = args[0] as *const u8;
392                 Self::unlink(pathname)
393             }
394             SYS_KILL => {
395                 let pid = Pid::new(args[0]);
396                 let sig = args[1] as c_int;
397                 // kdebug!("KILL SYSCALL RECEIVED");
398                 Self::kill(pid, sig)
399             }
400 
401             SYS_RT_SIGACTION => {
402                 let sig = args[0] as c_int;
403                 let act = args[1];
404                 let old_act = args[2];
405                 Self::sigaction(sig, act, old_act, frame.from_user())
406             }
407 
408             SYS_GETPID => Self::getpid().map(|pid| pid.into()),
409 
410             SYS_SCHED => Self::sched(frame.from_user()),
411             SYS_DUP => {
412                 let oldfd: i32 = args[0] as c_int;
413                 Self::dup(oldfd)
414             }
415 
416             #[cfg(target_arch = "x86_64")]
417             SYS_DUP2 => {
418                 let oldfd: i32 = args[0] as c_int;
419                 let newfd: i32 = args[1] as c_int;
420                 Self::dup2(oldfd, newfd)
421             }
422 
423             SYS_SOCKET => Self::socket(args[0], args[1], args[2]),
424             SYS_SETSOCKOPT => {
425                 let optval = args[3] as *const u8;
426                 let optlen = args[4] as usize;
427                 let virt_optval = VirtAddr::new(optval as usize);
428                 // 验证optval的地址是否合法
429                 if verify_area(virt_optval, optlen as usize).is_err() {
430                     // 地址空间超出了用户空间的范围,不合法
431                     Err(SystemError::EFAULT)
432                 } else {
433                     let data: &[u8] = unsafe { core::slice::from_raw_parts(optval, optlen) };
434                     Self::setsockopt(args[0], args[1], args[2], data)
435                 }
436             }
437             SYS_GETSOCKOPT => {
438                 let optval = args[3] as *mut u8;
439                 let optlen = args[4] as *mut usize;
440                 let virt_optval = VirtAddr::new(optval as usize);
441                 let virt_optlen = VirtAddr::new(optlen as usize);
442                 let security_check = || {
443                     // 验证optval的地址是否合法
444                     if verify_area(virt_optval, PAGE_4K_SIZE as usize).is_err() {
445                         // 地址空间超出了用户空间的范围,不合法
446                         return Err(SystemError::EFAULT);
447                     }
448 
449                     // 验证optlen的地址是否合法
450                     if verify_area(virt_optlen, core::mem::size_of::<u32>() as usize).is_err() {
451                         // 地址空间超出了用户空间的范围,不合法
452                         return Err(SystemError::EFAULT);
453                     }
454                     return Ok(());
455                 };
456                 let r = security_check();
457                 if r.is_err() {
458                     Err(r.unwrap_err())
459                 } else {
460                     Self::getsockopt(args[0], args[1], args[2], optval, optlen as *mut u32)
461                 }
462             }
463 
464             SYS_CONNECT => {
465                 let addr = args[1] as *const SockAddr;
466                 let addrlen = args[2] as usize;
467                 let virt_addr = VirtAddr::new(addr as usize);
468                 // 验证addr的地址是否合法
469                 if verify_area(virt_addr, addrlen as usize).is_err() {
470                     // 地址空间超出了用户空间的范围,不合法
471                     Err(SystemError::EFAULT)
472                 } else {
473                     Self::connect(args[0], addr, addrlen)
474                 }
475             }
476             SYS_BIND => {
477                 let addr = args[1] as *const SockAddr;
478                 let addrlen = args[2] as usize;
479                 let virt_addr = VirtAddr::new(addr as usize);
480                 // 验证addr的地址是否合法
481                 if verify_area(virt_addr, addrlen as usize).is_err() {
482                     // 地址空间超出了用户空间的范围,不合法
483                     Err(SystemError::EFAULT)
484                 } else {
485                     Self::bind(args[0], addr, addrlen)
486                 }
487             }
488 
489             SYS_SENDTO => {
490                 let buf = args[1] as *const u8;
491                 let len = args[2] as usize;
492                 let flags = args[3] as u32;
493                 let addr = args[4] as *const SockAddr;
494                 let addrlen = args[5] as usize;
495                 let virt_buf = VirtAddr::new(buf as usize);
496                 let virt_addr = VirtAddr::new(addr as usize);
497                 // 验证buf的地址是否合法
498                 if verify_area(virt_buf, len as usize).is_err() {
499                     // 地址空间超出了用户空间的范围,不合法
500                     Err(SystemError::EFAULT)
501                 } else if verify_area(virt_addr, addrlen as usize).is_err() {
502                     // 地址空间超出了用户空间的范围,不合法
503                     Err(SystemError::EFAULT)
504                 } else {
505                     let data: &[u8] = unsafe { core::slice::from_raw_parts(buf, len) };
506                     Self::sendto(args[0], data, flags, addr, addrlen)
507                 }
508             }
509 
510             SYS_RECVFROM => {
511                 let buf = args[1] as *mut u8;
512                 let len = args[2] as usize;
513                 let flags = args[3] as u32;
514                 let addr = args[4] as *mut SockAddr;
515                 let addrlen = args[5] as *mut usize;
516                 let virt_buf = VirtAddr::new(buf as usize);
517                 let virt_addrlen = VirtAddr::new(addrlen as usize);
518                 let virt_addr = VirtAddr::new(addr as usize);
519                 let security_check = || {
520                     // 验证buf的地址是否合法
521                     if verify_area(virt_buf, len as usize).is_err() {
522                         // 地址空间超出了用户空间的范围,不合法
523                         return Err(SystemError::EFAULT);
524                     }
525 
526                     // 验证addrlen的地址是否合法
527                     if verify_area(virt_addrlen, core::mem::size_of::<u32>() as usize).is_err() {
528                         // 地址空间超出了用户空间的范围,不合法
529                         return Err(SystemError::EFAULT);
530                     }
531 
532                     if verify_area(virt_addr, core::mem::size_of::<SockAddr>() as usize).is_err() {
533                         // 地址空间超出了用户空间的范围,不合法
534                         return Err(SystemError::EFAULT);
535                     }
536                     return Ok(());
537                 };
538                 let r = security_check();
539                 if r.is_err() {
540                     Err(r.unwrap_err())
541                 } else {
542                     let buf = unsafe { core::slice::from_raw_parts_mut(buf, len) };
543                     Self::recvfrom(args[0], buf, flags, addr, addrlen as *mut u32)
544                 }
545             }
546 
547             SYS_RECVMSG => {
548                 let msg = args[1] as *mut crate::net::syscall::MsgHdr;
549                 let flags = args[2] as u32;
550                 match UserBufferWriter::new(
551                     msg,
552                     core::mem::size_of::<crate::net::syscall::MsgHdr>(),
553                     true,
554                 ) {
555                     Err(e) => Err(e),
556                     Ok(mut user_buffer_writer) => {
557                         match user_buffer_writer.buffer::<crate::net::syscall::MsgHdr>(0) {
558                             Err(e) => Err(e),
559                             Ok(buffer) => {
560                                 let msg = &mut buffer[0];
561                                 Self::recvmsg(args[0], msg, flags)
562                             }
563                         }
564                     }
565                 }
566             }
567 
568             SYS_LISTEN => Self::listen(args[0], args[1]),
569             SYS_SHUTDOWN => Self::shutdown(args[0], args[1]),
570             SYS_ACCEPT => Self::accept(args[0], args[1] as *mut SockAddr, args[2] as *mut u32),
571             SYS_ACCEPT4 => Self::accept4(
572                 args[0],
573                 args[1] as *mut SockAddr,
574                 args[2] as *mut u32,
575                 args[3] as u32,
576             ),
577             SYS_GETSOCKNAME => {
578                 Self::getsockname(args[0], args[1] as *mut SockAddr, args[2] as *mut u32)
579             }
580             SYS_GETPEERNAME => {
581                 Self::getpeername(args[0], args[1] as *mut SockAddr, args[2] as *mut u32)
582             }
583             SYS_GETTIMEOFDAY => {
584                 let timeval = args[0] as *mut PosixTimeval;
585                 let timezone_ptr = args[1] as *mut PosixTimeZone;
586                 Self::gettimeofday(timeval, timezone_ptr)
587             }
588             SYS_MMAP => {
589                 let len = page_align_up(args[1]);
590                 let virt_addr = VirtAddr::new(args[0] as usize);
591                 if verify_area(virt_addr, len as usize).is_err() {
592                     Err(SystemError::EFAULT)
593                 } else {
594                     Self::mmap(
595                         VirtAddr::new(args[0]),
596                         len,
597                         args[2],
598                         args[3],
599                         args[4] as i32,
600                         args[5],
601                     )
602                 }
603             }
604             SYS_MUNMAP => {
605                 let addr = args[0];
606                 let len = page_align_up(args[1]);
607                 if addr & (MMArch::PAGE_SIZE - 1) != 0 {
608                     // The addr argument is not a multiple of the page size
609                     Err(SystemError::EINVAL)
610                 } else {
611                     Self::munmap(VirtAddr::new(addr), len)
612                 }
613             }
614             SYS_MPROTECT => {
615                 let addr = args[0];
616                 let len = page_align_up(args[1]);
617                 if addr & (MMArch::PAGE_SIZE - 1) != 0 {
618                     // The addr argument is not a multiple of the page size
619                     Err(SystemError::EINVAL)
620                 } else {
621                     Self::mprotect(VirtAddr::new(addr), len, args[2])
622                 }
623             }
624 
625             SYS_GETCWD => {
626                 let buf = args[0] as *mut u8;
627                 let size = args[1] as usize;
628                 let security_check = || {
629                     verify_area(VirtAddr::new(buf as usize), size)?;
630                     return Ok(());
631                 };
632                 let r = security_check();
633                 if r.is_err() {
634                     Err(r.unwrap_err())
635                 } else {
636                     let buf = unsafe { core::slice::from_raw_parts_mut(buf, size) };
637                     Self::getcwd(buf).map(|ptr| ptr.data())
638                 }
639             }
640 
641             SYS_GETPGID => Self::getpgid(Pid::new(args[0])).map(|pid| pid.into()),
642 
643             SYS_GETPPID => Self::getppid().map(|pid| pid.into()),
644             SYS_FSTAT => {
645                 let fd = args[0] as i32;
646                 let kstat = args[1] as *mut PosixKstat;
647                 let vaddr = VirtAddr::new(kstat as usize);
648                 // FIXME 由于c中的verify_area与rust中的verify_area重名,所以在引入时加了前缀区分
649                 // TODO 应该将用了c版本的verify_area都改为rust的verify_area
650                 match verify_area(vaddr, core::mem::size_of::<PosixKstat>()) {
651                     Ok(_) => Self::fstat(fd, kstat),
652                     Err(e) => Err(e),
653                 }
654             }
655 
656             SYS_FCNTL => {
657                 let fd = args[0] as i32;
658                 let cmd: Option<FcntlCommand> =
659                     <FcntlCommand as FromPrimitive>::from_u32(args[1] as u32);
660                 let arg = args[2] as i32;
661                 let res = if let Some(cmd) = cmd {
662                     Self::fcntl(fd, cmd, arg)
663                 } else {
664                     Err(SystemError::EINVAL)
665                 };
666 
667                 // kdebug!("FCNTL: fd: {}, cmd: {:?}, arg: {}, res: {:?}", fd, cmd, arg, res);
668                 res
669             }
670 
671             SYS_FTRUNCATE => {
672                 let fd = args[0] as i32;
673                 let len = args[1] as usize;
674                 let res = Self::ftruncate(fd, len);
675                 // kdebug!("FTRUNCATE: fd: {}, len: {}, res: {:?}", fd, len, res);
676                 res
677             }
678 
679             #[cfg(target_arch = "x86_64")]
680             SYS_MKNOD => {
681                 let path = args[0];
682                 let flags = args[1];
683                 let dev_t = args[2];
684                 let flags: ModeType = ModeType::from_bits_truncate(flags as u32);
685                 Self::mknod(path as *const i8, flags, DeviceNumber::from(dev_t as u32))
686             }
687 
688             SYS_CLONE => {
689                 let parent_tid = VirtAddr::new(args[2]);
690                 let child_tid = VirtAddr::new(args[3]);
691 
692                 // 地址校验
693                 verify_area(parent_tid, core::mem::size_of::<i32>())?;
694                 verify_area(child_tid, core::mem::size_of::<i32>())?;
695 
696                 let mut clone_args = KernelCloneArgs::new();
697                 clone_args.flags = CloneFlags::from_bits_truncate(args[0] as u64);
698                 clone_args.stack = args[1];
699                 clone_args.parent_tid = parent_tid;
700                 clone_args.child_tid = child_tid;
701                 clone_args.tls = args[4];
702                 Self::clone(frame, clone_args)
703             }
704 
705             SYS_FUTEX => {
706                 let uaddr = VirtAddr::new(args[0]);
707                 let operation = FutexFlag::from_bits(args[1] as u32).ok_or(SystemError::ENOSYS)?;
708                 let val = args[2] as u32;
709                 let utime = args[3];
710                 let uaddr2 = VirtAddr::new(args[4]);
711                 let val3 = args[5] as u32;
712 
713                 verify_area(uaddr, core::mem::size_of::<u32>())?;
714                 verify_area(uaddr2, core::mem::size_of::<u32>())?;
715 
716                 let mut timespec = None;
717                 if utime != 0 && operation.contains(FutexFlag::FLAGS_HAS_TIMEOUT) {
718                     let reader = UserBufferReader::new(
719                         utime as *const TimeSpec,
720                         core::mem::size_of::<TimeSpec>(),
721                         true,
722                     )?;
723 
724                     timespec = Some(reader.read_one_from_user::<TimeSpec>(0)?.clone());
725                 }
726 
727                 Self::do_futex(uaddr, operation, val, timespec, uaddr2, utime as u32, val3)
728             }
729 
730             SYS_READV => Self::readv(args[0] as i32, args[1], args[2]),
731             SYS_WRITEV => Self::writev(args[0] as i32, args[1], args[2]),
732 
733             SYS_SET_TID_ADDRESS => Self::set_tid_address(args[0]),
734 
735             #[cfg(target_arch = "x86_64")]
736             SYS_LSTAT => {
737                 let path: &CStr = unsafe { CStr::from_ptr(args[0] as *const c_char) };
738                 let path: Result<&str, core::str::Utf8Error> = path.to_str();
739                 let res = if path.is_err() {
740                     Err(SystemError::EINVAL)
741                 } else {
742                     let path: &str = path.unwrap();
743                     let kstat = args[1] as *mut PosixKstat;
744                     let vaddr = VirtAddr::new(kstat as usize);
745                     match verify_area(vaddr, core::mem::size_of::<PosixKstat>()) {
746                         Ok(_) => Self::lstat(path, kstat),
747                         Err(e) => Err(e),
748                     }
749                 };
750 
751                 res
752             }
753 
754             #[cfg(target_arch = "x86_64")]
755             SYS_STAT => {
756                 let path: &CStr = unsafe { CStr::from_ptr(args[0] as *const c_char) };
757                 let path: Result<&str, core::str::Utf8Error> = path.to_str();
758                 let res = if path.is_err() {
759                     Err(SystemError::EINVAL)
760                 } else {
761                     let path: &str = path.unwrap();
762                     let kstat = args[1] as *mut PosixKstat;
763                     let vaddr = VirtAddr::new(kstat as usize);
764                     match verify_area(vaddr, core::mem::size_of::<PosixKstat>()) {
765                         Ok(_) => Self::stat(path, kstat),
766                         Err(e) => Err(e),
767                     }
768                 };
769 
770                 res
771             }
772 
773             SYS_EPOLL_CREATE => Self::epoll_create(args[0] as i32),
774             SYS_EPOLL_CREATE1 => Self::epoll_create1(args[0]),
775 
776             SYS_EPOLL_CTL => Self::epoll_ctl(
777                 args[0] as i32,
778                 args[1],
779                 args[2] as i32,
780                 VirtAddr::new(args[3]),
781             ),
782 
783             SYS_EPOLL_WAIT => Self::epoll_wait(
784                 args[0] as i32,
785                 VirtAddr::new(args[1]),
786                 args[2] as i32,
787                 args[3] as i32,
788             ),
789 
790             SYS_EPOLL_PWAIT => {
791                 let epfd = args[0] as i32;
792                 let epoll_event = VirtAddr::new(args[1]);
793                 let max_events = args[2] as i32;
794                 let timespec = args[3] as i32;
795                 let sigmask_addr = args[4] as *mut SigSet;
796 
797                 if sigmask_addr.is_null() {
798                     return Self::epoll_wait(epfd, epoll_event, max_events, timespec);
799                 }
800                 let sigmask_reader =
801                     UserBufferReader::new(sigmask_addr, core::mem::size_of::<SigSet>(), true)?;
802                 let mut sigmask = sigmask_reader.read_one_from_user::<SigSet>(0)?.clone();
803 
804                 Self::epoll_pwait(
805                     args[0] as i32,
806                     VirtAddr::new(args[1]),
807                     args[2] as i32,
808                     args[3] as i32,
809                     &mut sigmask,
810                 )
811             }
812 
813             // 目前为了适配musl-libc,以下系统调用先这样写着
814             SYS_GETRANDOM => {
815                 let flags = GRandFlags::from_bits(args[2] as u8).ok_or(SystemError::EINVAL)?;
816                 Self::get_random(args[0] as *mut u8, args[1], flags)
817             }
818 
819             SYS_SOCKETPAIR => {
820                 unimplemented!()
821             }
822 
823             #[cfg(target_arch = "x86_64")]
824             SYS_POLL => {
825                 kwarn!("SYS_POLL has not yet been implemented");
826                 Ok(0)
827             }
828 
829             SYS_RT_SIGPROCMASK => {
830                 kwarn!("SYS_RT_SIGPROCMASK has not yet been implemented");
831                 Ok(0)
832             }
833 
834             SYS_TKILL => {
835                 kwarn!("SYS_TKILL has not yet been implemented");
836                 Ok(0)
837             }
838 
839             SYS_SIGALTSTACK => {
840                 kwarn!("SYS_SIGALTSTACK has not yet been implemented");
841                 Ok(0)
842             }
843 
844             SYS_EXIT_GROUP => {
845                 kwarn!("SYS_EXIT_GROUP has not yet been implemented");
846                 Ok(0)
847             }
848 
849             SYS_MADVISE => {
850                 // 这个太吵了,总是打印,先注释掉
851                 // kwarn!("SYS_MADVISE has not yet been implemented");
852                 Ok(0)
853             }
854             SYS_GETTID => Self::gettid().map(|tid| tid.into()),
855             SYS_GETUID => Self::getuid().map(|uid| uid.into()),
856 
857             SYS_SYSLOG => {
858                 let syslog_action_type = args[0] as usize;
859                 let buf_vaddr = args[1];
860                 let len = args[2];
861                 let from_user = frame.from_user();
862                 let mut user_buffer_writer =
863                     UserBufferWriter::new(buf_vaddr as *mut u8, len, from_user)?;
864 
865                 let user_buf = user_buffer_writer.buffer(0)?;
866                 let res = Self::do_syslog(syslog_action_type, user_buf, len);
867                 res
868             }
869 
870             SYS_GETGID => Self::getgid().map(|gid| gid.into()),
871             SYS_SETUID => {
872                 kwarn!("SYS_SETUID has not yet been implemented");
873                 Ok(0)
874             }
875             SYS_SETGID => {
876                 kwarn!("SYS_SETGID has not yet been implemented");
877                 Ok(0)
878             }
879             SYS_GETEUID => Self::geteuid().map(|euid| euid.into()),
880             SYS_GETEGID => Self::getegid().map(|egid| egid.into()),
881             SYS_GETRUSAGE => {
882                 let who = args[0] as c_int;
883                 let rusage = args[1] as *mut RUsage;
884                 Self::get_rusage(who, rusage)
885             }
886 
887             #[cfg(target_arch = "x86_64")]
888             SYS_READLINK => {
889                 let path = args[0] as *const u8;
890                 let buf = args[1] as *mut u8;
891                 let bufsiz = args[2] as usize;
892                 Self::readlink(path, buf, bufsiz)
893             }
894 
895             SYS_READLINKAT => {
896                 let dirfd = args[0] as i32;
897                 let pathname = args[1] as *const u8;
898                 let buf = args[2] as *mut u8;
899                 let bufsiz = args[3] as usize;
900                 Self::readlink_at(dirfd, pathname, buf, bufsiz)
901             }
902 
903             SYS_PRLIMIT64 => {
904                 let pid = args[0];
905                 let pid = Pid::new(pid);
906                 let resource = args[1];
907                 let new_limit = args[2] as *const RLimit64;
908                 let old_limit = args[3] as *mut RLimit64;
909 
910                 Self::prlimit64(pid, resource, new_limit, old_limit)
911             }
912 
913             #[cfg(target_arch = "x86_64")]
914             SYS_ACCESS => {
915                 let pathname = args[0] as *const u8;
916                 let mode = args[1] as u32;
917                 Self::access(pathname, mode)
918             }
919 
920             SYS_FACCESSAT => {
921                 let dirfd = args[0] as i32;
922                 let pathname = args[1] as *const u8;
923                 let mode = args[2] as u32;
924                 Self::faccessat2(dirfd, pathname, mode, 0)
925             }
926 
927             SYS_FACCESSAT2 => {
928                 let dirfd = args[0] as i32;
929                 let pathname = args[1] as *const u8;
930                 let mode = args[2] as u32;
931                 let flags = args[3] as u32;
932                 Self::faccessat2(dirfd, pathname, mode, flags)
933             }
934 
935             SYS_CLOCK_GETTIME => {
936                 let clockid = args[0] as i32;
937                 let timespec = args[1] as *mut TimeSpec;
938                 Self::clock_gettime(clockid, timespec)
939             }
940 
941             SYS_SYSINFO => {
942                 let info = args[0] as *mut SysInfo;
943                 Self::sysinfo(info)
944             }
945 
946             SYS_UMASK => {
947                 let mask = args[0] as u32;
948                 Self::umask(mask)
949             }
950 
951             #[cfg(target_arch = "x86_64")]
952             SYS_CHMOD => {
953                 let pathname = args[0] as *const u8;
954                 let mode = args[1] as u32;
955                 Self::chmod(pathname, mode)
956             }
957             SYS_FCHMOD => {
958                 let fd = args[0] as i32;
959                 let mode = args[1] as u32;
960                 Self::fchmod(fd, mode)
961             }
962             SYS_FCHMODAT => {
963                 let dirfd = args[0] as i32;
964                 let pathname = args[1] as *const u8;
965                 let mode = args[2] as u32;
966                 Self::fchmodat(dirfd, pathname, mode)
967             }
968 
969             SYS_SCHED_GETAFFINITY => {
970                 // todo: 这个系统调用还没有实现
971 
972                 Err(SystemError::ENOSYS)
973             }
974 
975             SYS_SCHED_YIELD => Self::sched_yield(),
976 
977             _ => panic!("Unsupported syscall ID: {}", syscall_num),
978         };
979 
980         return r;
981     }
982 
983     pub fn put_string(
984         s: *const u8,
985         front_color: u32,
986         back_color: u32,
987     ) -> Result<usize, SystemError> {
988         return Ok(unsafe { do_put_string(s, front_color, back_color) });
989     }
990 
991     pub fn reboot() -> Result<usize, SystemError> {
992         unsafe { cpu_reset() };
993     }
994 }
995