From 1435dd08968b351eeba8a816cab362a87073d9d1 Mon Sep 17 00:00:00 2001
From: Chen Chengjun <chenchengjun.ccj@antgroup.com>
Date: Wed, 10 Apr 2024 14:35:13 +0800
Subject: [PATCH] Add syscall nanosleep

---
 kernel/aster-nix/src/syscall/mod.rs           |  6 ++-
 .../{clock_nanosleep.rs => nanosleep.rs}      | 54 ++++++++++++++-----
 2 files changed, 46 insertions(+), 14 deletions(-)
 rename kernel/aster-nix/src/syscall/{clock_nanosleep.rs => nanosleep.rs} (55%)

diff --git a/kernel/aster-nix/src/syscall/mod.rs b/kernel/aster-nix/src/syscall/mod.rs
index 1c80dcbaf..acec14877 100644
--- a/kernel/aster-nix/src/syscall/mod.rs
+++ b/kernel/aster-nix/src/syscall/mod.rs
@@ -27,7 +27,6 @@ use crate::{
         chown::{sys_chown, sys_fchown, sys_fchownat, sys_lchown},
         chroot::sys_chroot,
         clock_gettime::sys_clock_gettime,
-        clock_nanosleep::sys_clock_nanosleep,
         clone::sys_clone,
         close::sys_close,
         dup::{sys_dup, sys_dup2},
@@ -59,6 +58,7 @@ use crate::{
         mmap::sys_mmap,
         mprotect::sys_mprotect,
         munmap::sys_munmap,
+        nanosleep::{sys_clock_nanosleep, sys_nanosleep},
         open::{sys_open, sys_openat},
         pause::sys_pause,
         pipe::{sys_pipe, sys_pipe2},
@@ -107,7 +107,6 @@ mod chmod;
 mod chown;
 mod chroot;
 mod clock_gettime;
-mod clock_nanosleep;
 mod clone;
 mod close;
 mod connect;
@@ -150,6 +149,7 @@ mod mkdir;
 mod mmap;
 mod mprotect;
 mod munmap;
+mod nanosleep;
 mod open;
 mod pause;
 mod pipe;
@@ -261,6 +261,7 @@ define_syscall_nums!(
     SYS_DUP = 32,
     SYS_DUP2 = 33,
     SYS_PAUSE = 34,
+    SYS_NANOSLEEP = 35,
     SYS_ALARM = 37,
     SYS_GETPID = 39,
     SYS_SOCKET = 41,
@@ -449,6 +450,7 @@ pub fn syscall_dispatch(
         SYS_DUP => syscall_handler!(1, sys_dup, args),
         SYS_DUP2 => syscall_handler!(2, sys_dup2, args),
         SYS_PAUSE => syscall_handler!(0, sys_pause),
+        SYS_NANOSLEEP => syscall_handler!(2, sys_nanosleep, args),
         SYS_ALARM => syscall_handler!(1, sys_alarm, args),
         SYS_GETPID => syscall_handler!(0, sys_getpid),
         SYS_SOCKET => syscall_handler!(3, sys_socket, args),
diff --git a/kernel/aster-nix/src/syscall/clock_nanosleep.rs b/kernel/aster-nix/src/syscall/nanosleep.rs
similarity index 55%
rename from kernel/aster-nix/src/syscall/clock_nanosleep.rs
rename to kernel/aster-nix/src/syscall/nanosleep.rs
index 95b34e6f9..88ab63156 100644
--- a/kernel/aster-nix/src/syscall/clock_nanosleep.rs
+++ b/kernel/aster-nix/src/syscall/nanosleep.rs
@@ -2,7 +2,7 @@
 
 use core::time::Duration;
 
-use super::{SyscallReturn, SYS_CLOCK_NANOSLEEP};
+use super::{SyscallReturn, SYS_CLOCK_NANOSLEEP, SYS_NANOSLEEP};
 use crate::{
     log_syscall_entry,
     prelude::*,
@@ -11,6 +11,16 @@ use crate::{
     util::{read_val_from_user, write_val_to_user},
 };
 
+pub fn sys_nanosleep(
+    request_timespec_addr: Vaddr,
+    remain_timespec_addr: Vaddr,
+) -> Result<SyscallReturn> {
+    log_syscall_entry!(SYS_NANOSLEEP);
+    let clock_id = ClockID::CLOCK_MONOTONIC;
+
+    do_clock_nanosleep(clock_id, false, request_timespec_addr, remain_timespec_addr)
+}
+
 pub fn sys_clock_nanosleep(
     clockid: clockid_t,
     flags: i32,
@@ -19,7 +29,7 @@ pub fn sys_clock_nanosleep(
 ) -> Result<SyscallReturn> {
     log_syscall_entry!(SYS_CLOCK_NANOSLEEP);
     let clock_id = ClockID::try_from(clockid)?;
-    let abs_time = if flags == 0 {
+    let is_abs_time = if flags == 0 {
         false
     } else if flags == TIMER_ABSTIME {
         true
@@ -27,37 +37,57 @@ pub fn sys_clock_nanosleep(
         unreachable!()
     };
 
-    let duration = {
+    do_clock_nanosleep(
+        clock_id,
+        is_abs_time,
+        request_timespec_addr,
+        remain_timespec_addr,
+    )
+}
+
+fn do_clock_nanosleep(
+    clock_id: ClockID,
+    is_abs_time: bool,
+    request_timespec_addr: Vaddr,
+    remain_timespec_addr: Vaddr,
+) -> Result<SyscallReturn> {
+    let request_time = {
         let timespec = read_val_from_user::<timespec_t>(request_timespec_addr)?;
-        if abs_time {
-            todo!("deal with abs time");
-        }
         Duration::from(timespec)
     };
 
     debug!(
-        "clockid = {:?}, abs_time = {}, duration = {:?}, remain_timespec_addr = 0x{:x}",
-        clock_id, abs_time, duration, remain_timespec_addr
+        "clockid = {:?}, is_abs_time = {}, request_time = {:?}, remain_timespec_addr = 0x{:x}",
+        clock_id, is_abs_time, request_time, remain_timespec_addr
     );
 
     let start_time = now_as_duration(&clock_id)?;
+    let timeout = if is_abs_time {
+        if request_time < start_time {
+            return Ok(SyscallReturn::Return(0));
+        }
+
+        request_time - start_time
+    } else {
+        request_time
+    };
 
     // FIXME: sleeping thread can only be interrupted by signals that will call signal handler or terminate
     // current process. i.e., the signals that should be ignored will not interrupt sleeping thread.
     let pauser = Pauser::new();
 
-    let res = pauser.pause_until_or_timeout(|| None, &duration);
+    let res = pauser.pause_until_or_timeout(|| None, &timeout);
     match res {
         Err(e) if e.error() == Errno::ETIME => Ok(SyscallReturn::Return(0)),
         Err(e) if e.error() == Errno::EINTR => {
             let end_time = now_as_duration(&clock_id)?;
 
-            if end_time >= start_time + duration {
+            if end_time >= start_time + timeout {
                 return Ok(SyscallReturn::Return(0));
             }
 
-            if remain_timespec_addr != 0 {
-                let remaining_duration = (start_time + duration) - end_time;
+            if remain_timespec_addr != 0 && !is_abs_time {
+                let remaining_duration = (start_time + timeout) - end_time;
                 let remaining_timespec = timespec_t::from(remaining_duration);
                 write_val_to_user(remain_timespec_addr, &remaining_timespec)?;
             }