lab04: sys_get_time

os/src/syscall/process.rs

@@ -1,8 +1,8 @@
 //! Process management syscalls
 
 use crate::config::PAGE_SIZE;
-use crate::mm::{MapPermission, VPNRange, VirtAddr};
+use crate::mm::{translated_byte_buffer, MapPermission, VPNRange, VirtAddr};
-use crate::task::{change_program_brk, create_new_map_area, exit_current_and_run_next, get_current_task_page_table_entry, suspend_current_and_run_next, unmap_virtual_page};
+use crate::task::{change_program_brk, create_new_map_area, current_user_token, exit_current_and_run_next, get_current_task_page_table_entry, suspend_current_and_run_next, unmap_virtual_page};
 use crate::timer::get_time_us;
 
 /// task exits and submit an exit code
@@ -28,14 +28,27 @@ pub struct TimeVal {
 /// get current time
 pub fn sys_get_time(ts: *mut TimeVal, _tz: usize) -> isize {
     let us = get_time_us();
-    unsafe {
+    let dst_vec = translated_byte_buffer(
-        *ts = TimeVal {
+        current_user_token(),
+        ts as *const u8, core::mem::size_of::<TimeVal>()
+    );
+    let ref time_val = TimeVal {
         sec: us / 1_000_000,
         usec: us % 1_000_000,
     };
+    let src_ptr = time_val as *const TimeVal;
+    for (idx, dst) in dst_vec.into_iter().enumerate() {
+        let unit_len = dst.len();
+        unsafe {
+            dst.copy_from_slice(
+                core::slice::from_raw_parts(
+                    src_ptr.wrapping_byte_add(idx * unit_len) as *const u8,
+                    unit_len
+                )
+            );
+        }
     }
     0
-    -1
 }
 
 /// change data segment size

user/src/syscall.rs

@@ -6,7 +6,6 @@ const SYSCALL_WRITE: usize = 64;
 const SYSCALL_EXIT: usize = 93;
 const SYSCALL_YIELD: usize = 124;
 const SYSCALL_GET_TIME: usize = 169;
-const SYSCALL_GETTIMEOFDAY: usize = 169;
 const SYSCALL_SBRK: usize = 214;
 const SYSCALL_MMAP: usize = 222;
 const SYSCALL_MUNMAP: usize = 215;
@@ -38,7 +37,7 @@ pub fn sys_yield() -> isize {
 }
 
 pub fn sys_get_time(time: &TimeVal, tz: usize) -> isize {
-    syscall(SYSCALL_GETTIMEOFDAY, [time as *const _ as usize, tz, 0])
+    syscall(SYSCALL_GET_TIME, [time as *const _ as usize, tz, 0])
 }
 
 pub fn sys_sbrk(size: i32) -> isize {