Refactor project structure

kernel/comps/network/src/buffer.rs

@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: MPL-2.0
+
+use core::mem::size_of;
+
+use align_ext::AlignExt;
+use bytes::BytesMut;
+use pod::Pod;
+
+/// Buffer for receive packet
+#[derive(Debug)]
+pub struct RxBuffer {
+    /// Packet Buffer, length align 8.
+    buf: BytesMut,
+    /// Header len
+    header_len: usize,
+    /// Packet len
+    packet_len: usize,
+}
+
+impl RxBuffer {
+    pub fn new(len: usize, header_len: usize) -> Self {
+        let len = len.align_up(8);
+        let buf = BytesMut::zeroed(len);
+        Self {
+            buf,
+            packet_len: 0,
+            header_len,
+        }
+    }
+
+    pub const fn packet_len(&self) -> usize {
+        self.packet_len
+    }
+
+    pub fn set_packet_len(&mut self, packet_len: usize) {
+        self.packet_len = packet_len;
+    }
+
+    pub fn buf(&self) -> &[u8] {
+        &self.buf
+    }
+
+    pub fn buf_mut(&mut self) -> &mut [u8] {
+        &mut self.buf
+    }
+
+    /// Packet payload slice, which is inner buffer excluding VirtioNetHdr.
+    pub fn packet(&self) -> &[u8] {
+        debug_assert!(self.header_len + self.packet_len <= self.buf.len());
+        &self.buf[self.header_len..self.header_len + self.packet_len]
+    }
+
+    /// Mutable packet payload slice.
+    pub fn packet_mut(&mut self) -> &mut [u8] {
+        debug_assert!(self.header_len + self.packet_len <= self.buf.len());
+        &mut self.buf[self.header_len..self.header_len + self.packet_len]
+    }
+
+    pub fn header<H: Pod>(&self) -> H {
+        debug_assert_eq!(size_of::<H>(), self.header_len);
+        H::from_bytes(&self.buf[..size_of::<H>()])
+    }
+}
+
+/// Buffer for transmit packet
+#[derive(Debug)]
+pub struct TxBuffer {
+    buf: BytesMut,
+}
+
+impl TxBuffer {
+    pub fn with_len(buf_len: usize) -> Self {
+        Self {
+            buf: BytesMut::zeroed(buf_len),
+        }
+    }
+
+    pub fn new(buf: &[u8]) -> Self {
+        Self {
+            buf: BytesMut::from(buf),
+        }
+    }
+
+    pub fn buf(&self) -> &[u8] {
+        &self.buf
+    }
+
+    pub fn buf_mut(&mut self) -> &mut [u8] {
+        &mut self.buf
+    }
+}