runtime-rs: implement trait for vhost-user device

add the trait implementation for vhost-user device

Fixes:#5375
Signed-off-by: Zhongtao Hu <zhongtaohu.tim@linux.alibaba.com>

src/runtime-rs/crates/hypervisor/src/device/driver/mod.rs

@@ -4,6 +4,7 @@
 // SPDX-License-Identifier: Apache-2.0
 //
 
+mod vhost_user;
 mod virtio_blk;
 pub use virtio_blk::{
     BlockConfig, KATA_BLK_DEV_TYPE, KATA_MMIO_BLK_DEV_TYPE, VIRTIO_BLOCK_MMIO, VIRTIO_BLOCK_PCI,

src/runtime-rs/crates/hypervisor/src/device/driver/vhost_user.rs

@@ -0,0 +1,53 @@
+// Copyright (c) 2019-2023 Alibaba Cloud
+// Copyright (c) 2019-2023 Ant Group
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+
+use crate::Device;
+use crate::{driver::hypervisor, DeviceConfig};
+use anyhow::Result;
+use async_trait::async_trait;
+
+/// VhostUserConfig represents data shared by most vhost-user devices
+pub struct VhostUserConfig {
+    /// Device id
+    pub dev_id: String,
+    /// Socket path
+    pub socket_path: String,
+    /// Mac_address is only meaningful for vhost user net device
+    pub mac_address: String,
+    /// These are only meaningful for vhost user fs devices
+    pub tag: String,
+    pub cache: String,
+    pub device_type: String,
+    /// Pci_addr is the PCI address used to identify the slot at which the drive is attached.
+    pub pci_addr: Option<String>,
+    /// Block index of the device if assigned
+    pub index: u8,
+    pub cache_size: u32,
+    pub queue_siez: u32,
+}
+
+#[async_trait]
+impl Device for VhostUserConfig {
+    async fn attach(&self, _h: &dyn hypervisor) -> Result<()> {
+        todo!()
+    }
+
+    async fn detach(&self, _h: &dyn hypervisor) -> Result<u64> {
+        todo!()
+    }
+
+    async fn get_device_info(&self) -> DeviceConfig {
+        todo!()
+    }
+
+    async fn increase_attach_count(&mut self) -> Result<bool> {
+        todo!()
+    }
+
+    async fn decrease_attach_count(&mut self) -> Result<bool> {
+        todo!()
+    }
+}