实现SystemV共享内存 (#690)

* 实现SystemV共享内存

* 测试shm

* 添加测试程序

* 完善细节

* 修正shm的时间数据错误的问题

* fix: devfs的metadata权限为0x777的错误

---------

Co-authored-by: longjin <longjin@DragonOS.org>

kernel/src/net/event_poll/mod.rs

@@ -26,7 +26,7 @@ use crate::{
     sched::{schedule, SchedMode},
     time::{
         timer::{next_n_us_timer_jiffies, Timer, WakeUpHelper},
-        TimeSpec,
+        PosixTimeSpec,
     },
 };
 
@@ -394,7 +394,7 @@ impl EventPoll {
         epfd: i32,
         epoll_event: &mut [EPollEvent],
         max_events: i32,
-        timespec: Option<TimeSpec>,
+        timespec: Option<PosixTimeSpec>,
     ) -> Result<usize, SystemError> {
         let current_pcb = ProcessManager::current_pcb();
         let fd_table = current_pcb.fd_table();

kernel/src/net/event_poll/syscall.rs

@@ -9,7 +9,7 @@ use crate::{
         user_access::{UserBufferReader, UserBufferWriter},
         Syscall,
     },
-    time::TimeSpec,
+    time::PosixTimeSpec,
 };
 
 use super::{EPollCtlOption, EPollEvent, EventPoll};
@@ -42,14 +42,14 @@ impl Syscall {
 
         let mut timespec = None;
         if timeout == 0 {
-            timespec = Some(TimeSpec::new(0, 0));
+            timespec = Some(PosixTimeSpec::new(0, 0));
         }
 
         if timeout > 0 {
             let sec: i64 = timeout as i64 / 1000;
             let nsec: i64 = 1000000 * (timeout as i64 % 1000);
 
-            timespec = Some(TimeSpec::new(sec, nsec))
+            timespec = Some(PosixTimeSpec::new(sec, nsec))
         }
 
         // 从用户传入的地址中拿到epoll_events