From 2d732a48d8a3c87bd5ce3a0382d4129eda44c879 Mon Sep 17 00:00:00 2001
From: gjz010 <gjz010944@gmail.com>
Date: Tue, 11 May 2021 02:09:52 +0800
Subject: [PATCH] Serial device file for user using 2nd UART.

---
 kernel/src/fs/devfs/mod.rs    |  2 +
 kernel/src/fs/devfs/serial.rs | 78 +++++++++++++++++++++++++++++++++++
 kernel/src/fs/mod.rs          |  6 ++-
 3 files changed, 85 insertions(+), 1 deletion(-)
 create mode 100644 kernel/src/fs/devfs/serial.rs

diff --git a/kernel/src/fs/devfs/mod.rs b/kernel/src/fs/devfs/mod.rs
index 0e590734..4d7dfdcc 100644
--- a/kernel/src/fs/devfs/mod.rs
+++ b/kernel/src/fs/devfs/mod.rs
@@ -2,10 +2,12 @@
 
 mod fbdev;
 mod random;
+mod serial;
 mod shm;
 mod tty;
 
 pub use fbdev::*;
 pub use random::*;
+pub use serial::*;
 pub use shm::*;
 pub use tty::*;
diff --git a/kernel/src/fs/devfs/serial.rs b/kernel/src/fs/devfs/serial.rs
new file mode 100644
index 00000000..39b9e8e9
--- /dev/null
+++ b/kernel/src/fs/devfs/serial.rs
@@ -0,0 +1,78 @@
+use crate::drivers::serial::SERIAL_ACTIVITY;
+use crate::drivers::SerialDriver;
+use crate::drivers::SERIAL_DRIVERS;
+use crate::syscall::spin_and_wait;
+use alloc::sync::Arc;
+use alloc::vec::Vec;
+use core::any::Any;
+use rcore_fs::vfs::*;
+pub struct Serial {
+    id: usize,
+    driver: Arc<dyn SerialDriver>,
+}
+
+impl Serial {
+    pub fn new(id: usize, driver: Arc<dyn SerialDriver>) -> Self {
+        Serial { id, driver }
+    }
+    pub fn wrap_all_serial_devices() -> Vec<Self> {
+        let drivers = SERIAL_DRIVERS.read();
+        drivers
+            .iter()
+            .cloned()
+            .enumerate()
+            .map(|(i, x)| Serial::new(i, x))
+            .collect()
+    }
+}
+
+impl INode for Serial {
+    fn read_at(&self, _offset: usize, buf: &mut [u8]) -> Result<usize> {
+        let mut n = 0;
+        for r in buf.iter_mut() {
+            if let Some(x) = self.driver.try_read() {
+                *r = x;
+                n += 1;
+            } else {
+                break;
+            }
+        }
+        Ok(n)
+    }
+
+    fn write_at(&self, _offset: usize, buf: &[u8]) -> Result<usize> {
+        self.driver.write(buf);
+        Ok(buf.len())
+    }
+
+    fn poll(&self) -> Result<PollStatus> {
+        Ok(PollStatus {
+            read: true,
+            write: true,
+            error: false,
+        })
+    }
+
+    fn metadata(&self) -> Result<Metadata> {
+        Ok(Metadata {
+            dev: 1,
+            inode: 1,
+            size: 0,
+            blk_size: 0,
+            blocks: 0,
+            atime: Timespec { sec: 0, nsec: 0 },
+            mtime: Timespec { sec: 0, nsec: 0 },
+            ctime: Timespec { sec: 0, nsec: 0 },
+            type_: FileType::CharDevice,
+            mode: 0o666,
+            nlinks: 1,
+            uid: 0,
+            gid: 0,
+            rdev: make_rdev(4, self.id),
+        })
+    }
+
+    fn as_any_ref(&self) -> &dyn Any {
+        self
+    }
+}
diff --git a/kernel/src/fs/mod.rs b/kernel/src/fs/mod.rs
index ef9af81f..eddebd61 100644
--- a/kernel/src/fs/mod.rs
+++ b/kernel/src/fs/mod.rs
@@ -11,7 +11,7 @@ use rcore_fs_sfs::{INodeImpl, SimpleFileSystem};
 
 use self::devfs::{Fbdev, RandomINode};
 
-pub use self::devfs::{ShmINode, TTY};
+pub use self::devfs::{Serial, ShmINode, TTY};
 pub use self::file::*;
 pub use self::file_like::*;
 pub use self::pipe::Pipe;
@@ -82,6 +82,10 @@ lazy_static! {
         devfs.add("tty", TTY.clone()).expect("failed to mknod /dev/tty");
         devfs.add("fb0", Arc::new(Fbdev::default())).expect("failed to mknod /dev/fb0");
         devfs.add("shm", Arc::new(ShmINode::default())).expect("failed to mkdir shm");
+        for (i, serial) in Serial::wrap_all_serial_devices().into_iter().enumerate(){
+            devfs.add(&format!("ttyS{}", i), Arc::new(serial)).expect("failed to add a serial");
+        }
+
 
         #[cfg(feature = "hypervisor")]
         devfs.add("rvm", Arc::new(crate::rvm::RvmINode::new())).expect("failed to mknod /dev/rvm");