Implement dummy metadata() for epoll and socket files

kernel/src/fs/epoll/epoll_file.rs

@@ -12,7 +12,10 @@ use ostd::sync::LocalIrqDisabled;
 use super::*;
 use crate::{
     events::Observer,
-    fs::{file_handle::FileLike, utils::IoctlCmd},
+    fs::{
+        file_handle::FileLike,
+        utils::{InodeMode, IoctlCmd, Metadata},
+    },
     process::signal::{Pollable, Pollee, Poller},
 };
 
@@ -341,7 +344,6 @@ impl Pollable for EpollFile {
     }
 }
 
-// Implement the common methods required by FileHandle
 impl FileLike for EpollFile {
     fn read(&self, _writer: &mut VmWriter) -> Result<usize> {
         return_errno_with_message!(Errno::EINVAL, "epoll files do not support read");
@@ -370,6 +372,16 @@ impl FileLike for EpollFile {
     ) -> Option<Weak<dyn Observer<IoEvents>>> {
         self.pollee.unregister_observer(observer)
     }
+
+    fn metadata(&self) -> Metadata {
+        // This is a dummy implementation.
+        // TODO: Add "anonymous inode fs" and link `EpollFile` to it.
+        Metadata::new_file(
+            0,
+            InodeMode::from_bits_truncate(0o600),
+            aster_block::BLOCK_SIZE,
+        )
+    }
 }
 
 /// An epoll entry that is contained in an epoll file.

kernel/src/fs/file_handle.rs

@@ -54,9 +54,8 @@ pub trait FileLike: Pollable + Send + Sync + Any {
         return_errno_with_message!(Errno::EINVAL, "resize is not supported");
     }
 
-    fn metadata(&self) -> Metadata {
-        panic!("metadata unsupported");
-    }
+    /// Get the metadata that describes this file.
+    fn metadata(&self) -> Metadata;
 
     fn mode(&self) -> Result<InodeMode> {
         return_errno_with_message!(Errno::EINVAL, "mode is not supported");

kernel/src/fs/pipe.rs

@@ -84,6 +84,8 @@ impl FileLike for PipeReader {
     }
 
     fn metadata(&self) -> Metadata {
+        // This is a dummy implementation.
+        // TODO: Add "PipeFS" and link `PipeReader` to it.
         let now = RealTimeCoarseClock::get().read_time();
         Metadata {
             dev: 0,
@@ -166,6 +168,8 @@ impl FileLike for PipeWriter {
     }
 
     fn metadata(&self) -> Metadata {
+        // This is a dummy implementation.
+        // TODO: Add "PipeFS" and link `PipeWriter` to it.
         let now = RealTimeCoarseClock::get().read_time();
         Metadata {
             dev: 0,

kernel/src/net/socket/ip/datagram/mod.rs

@@ -9,7 +9,10 @@ use self::{bound::BoundDatagram, unbound::UnboundDatagram};
 use super::{common::get_ephemeral_endpoint, UNSPECIFIED_LOCAL_ENDPOINT};
 use crate::{
     events::{IoEvents, Observer},
-    fs::{file_handle::FileLike, utils::StatusFlags},
+    fs::{
+        file_handle::FileLike,
+        utils::{InodeMode, Metadata, StatusFlags},
+    },
     match_sock_option_mut,
     net::{
         iface::poll_ifaces,
@@ -271,6 +274,16 @@ impl FileLike for DatagramSocket {
     ) -> Option<Weak<dyn Observer<IoEvents>>> {
         self.pollee.unregister_observer(observer)
     }
+
+    fn metadata(&self) -> Metadata {
+        // This is a dummy implementation.
+        // TODO: Add "SockFS" and link `DatagramSocket` to it.
+        Metadata::new_socket(
+            0,
+            InodeMode::from_bits_truncate(0o140777),
+            aster_block::BLOCK_SIZE,
+        )
+    }
 }
 
 impl Socket for DatagramSocket {

kernel/src/net/socket/ip/stream/mod.rs

@@ -15,7 +15,10 @@ use util::TcpOptionSet;
 use super::UNSPECIFIED_LOCAL_ENDPOINT;
 use crate::{
     events::{IoEvents, Observer},
-    fs::{file_handle::FileLike, utils::StatusFlags},
+    fs::{
+        file_handle::FileLike,
+        utils::{InodeMode, Metadata, StatusFlags},
+    },
     match_sock_option_mut, match_sock_option_ref,
     net::{
         iface::poll_ifaces,
@@ -428,6 +431,16 @@ impl FileLike for StreamSocket {
     ) -> Option<Weak<dyn Observer<IoEvents>>> {
         self.pollee.unregister_observer(observer)
     }
+
+    fn metadata(&self) -> Metadata {
+        // This is a dummy implementation.
+        // TODO: Add "SockFS" and link `StreamSocket` to it.
+        Metadata::new_socket(
+            0,
+            InodeMode::from_bits_truncate(0o140777),
+            aster_block::BLOCK_SIZE,
+        )
+    }
 }
 
 impl Socket for StreamSocket {

kernel/src/net/socket/unix/stream/socket.rs

@@ -11,7 +11,10 @@ use super::{
 };
 use crate::{
     events::{IoEvents, Observer},
-    fs::{file_handle::FileLike, utils::StatusFlags},
+    fs::{
+        file_handle::FileLike,
+        utils::{InodeMode, Metadata, StatusFlags},
+    },
     net::socket::{
         unix::UnixSocketAddr,
         util::{send_recv_flags::SendRecvFlags, socket_addr::SocketAddr, MessageHeader},
@@ -213,6 +216,16 @@ impl FileLike for UnixStreamSocket {
             State::Connected(connected) => connected.unregister_observer(observer),
         }
     }
+
+    fn metadata(&self) -> Metadata {
+        // This is a dummy implementation.
+        // TODO: Add "SockFS" and link `UnixStreamSocket` to it.
+        Metadata::new_socket(
+            0,
+            InodeMode::from_bits_truncate(0o140777),
+            aster_block::BLOCK_SIZE,
+        )
+    }
 }
 
 impl Socket for UnixStreamSocket {

kernel/src/net/socket/vsock/stream/socket.rs

@@ -5,7 +5,10 @@ use core::sync::atomic::{AtomicBool, Ordering};
 use super::{connected::Connected, connecting::Connecting, init::Init, listen::Listen};
 use crate::{
     events::IoEvents,
-    fs::{file_handle::FileLike, utils::StatusFlags},
+    fs::{
+        file_handle::FileLike,
+        utils::{InodeMode, Metadata, StatusFlags},
+    },
     net::socket::{
         vsock::{addr::VsockSocketAddr, VSOCK_GLOBAL},
         MessageHeader, SendRecvFlags, SockShutdownCmd, Socket, SocketAddr,
@@ -171,6 +174,16 @@ impl FileLike for VsockStreamSocket {
         }
         Ok(())
     }
+
+    fn metadata(&self) -> Metadata {
+        // This is a dummy implementation.
+        // TODO: Add "SockFS" and link `VsockStreamSocket` to it.
+        Metadata::new_socket(
+            0,
+            InodeMode::from_bits_truncate(0o140777),
+            aster_block::BLOCK_SIZE,
+        )
+    }
 }
 
 impl Socket for VsockStreamSocket {

kernel/src/syscall/eventfd.rs

@@ -262,6 +262,8 @@ impl FileLike for EventFile {
     }
 
     fn metadata(&self) -> Metadata {
+        // This is a dummy implementation.
+        // TODO: Add "anonymous inode fs" and link `EventFile` to it.
         let now = RealTimeClock::get().read_time();
         Metadata {
             dev: 0,