feat(tty): 将tty设备适配epoll，修改串口部分问题 (#968)

- tty文件适配epoll，使epoll能够监听tty
- 修改串口handle_irq，原有每次只读取一个字节会导致：输入left(esc+[+A)被错误解析为(esc)+([)+(A)三个字符
- 为串口加上vcdata用于控制输入输出的格式问题（未解决，这个pr捎带）

kernel/src/net/event_poll/mod.rs

@@ -716,41 +716,50 @@ impl EventPoll {
     /// ### epoll的回调，支持epoll的文件有事件到来时直接调用该方法即可
     pub fn wakeup_epoll(
         epitems: &SpinLock<LinkedList<Arc<EPollItem>>>,
-        pollflags: EPollEventType,
+        pollflags: Option<EPollEventType>,
     ) -> Result<(), SystemError> {
         let mut epitems_guard = epitems.try_lock_irqsave()?;
         // 一次只取一个，因为一次也只有一个进程能拿到对应文件的🔓
         if let Some(epitem) = epitems_guard.pop_front() {
-            let epoll = epitem.epoll().upgrade().unwrap();
-            let mut epoll_guard = epoll.try_lock()?;
-            let binding = epitem.clone();
-            let event_guard = binding.event().read();
-            let ep_events = EPollEventType::from_bits_truncate(event_guard.events());
+            let pollflags = pollflags.unwrap_or({
+                if let Some(file) = epitem.file.upgrade() {
+                    EPollEventType::from_bits_truncate(file.poll()? as u32)
+                } else {
+                    EPollEventType::empty()
+                }
+            });
 
-            // 检查事件合理性以及是否有感兴趣的事件
-            if !(ep_events
-                .difference(EPollEventType::EP_PRIVATE_BITS)
-                .is_empty()
-                || pollflags.difference(ep_events).is_empty())
-            {
-                // TODO: 未处理pm相关
+            if let Some(epoll) = epitem.epoll().upgrade() {
+                let mut epoll_guard = epoll.try_lock()?;
+                let binding = epitem.clone();
+                let event_guard = binding.event().read();
+                let ep_events = EPollEventType::from_bits_truncate(event_guard.events());
 
-                // 首先将就绪的epitem加入等待队列
-                epoll_guard.ep_add_ready(epitem.clone());
+                // 检查事件合理性以及是否有感兴趣的事件
+                if !(ep_events
+                    .difference(EPollEventType::EP_PRIVATE_BITS)
+                    .is_empty()
+                    || pollflags.difference(ep_events).is_empty())
+                {
+                    // TODO: 未处理pm相关
 
-                if epoll_guard.ep_has_waiter() {
-                    if ep_events.contains(EPollEventType::EPOLLEXCLUSIVE)
-                        && !pollflags.contains(EPollEventType::POLLFREE)
-                    {
-                        // 避免惊群
-                        epoll_guard.ep_wake_one();
-                    } else {
-                        epoll_guard.ep_wake_all();
+                    // 首先将就绪的epitem加入等待队列
+                    epoll_guard.ep_add_ready(epitem.clone());
+
+                    if epoll_guard.ep_has_waiter() {
+                        if ep_events.contains(EPollEventType::EPOLLEXCLUSIVE)
+                            && !pollflags.contains(EPollEventType::POLLFREE)
+                        {
+                            // 避免惊群
+                            epoll_guard.ep_wake_one();
+                        } else {
+                            epoll_guard.ep_wake_all();
+                        }
                     }
                 }
-            }
 
-            epitems_guard.push_back(epitem);
+                epitems_guard.push_back(epitem);
+            }
         }
         Ok(())
     }

kernel/src/net/net_core.rs

@@ -233,7 +233,7 @@ fn send_event(sockets: &smoltcp::iface::SocketSet) -> Result<(), SystemError> {
         }
         EventPoll::wakeup_epoll(
             &posix_item.epitems,
-            EPollEventType::from_bits_truncate(events as u32),
+            Some(EPollEventType::from_bits_truncate(events as u32)),
         )?;
         drop(handle_guard);
         // crate::debug!(