From 69a5e5b955f2843e03148c6ea67bcc1eb584a2eb Mon Sep 17 00:00:00 2001
From: Alex Lyn <alex.lyn@antgroup.com>
Date: Tue, 12 Mar 2024 22:18:01 +0800
Subject: [PATCH] runtime-rs: add network device handler in start_vm.

Add network device handler in start_vm, which is sepcially
for Qemu VM running with added net params to command line.

Fixes: #8865

Signed-off-by: Alex Lyn <alex.lyn@antgroup.com>
---
 .../hypervisor/src/qemu/cmdline_generator.rs    | 17 +++++++++++++++--
 .../crates/hypervisor/src/qemu/inner.rs         | 14 ++++++++++++--
 2 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/src/runtime-rs/crates/hypervisor/src/qemu/cmdline_generator.rs b/src/runtime-rs/crates/hypervisor/src/qemu/cmdline_generator.rs
index 17b57c9322..9f79a096e4 100644
--- a/src/runtime-rs/crates/hypervisor/src/qemu/cmdline_generator.rs
+++ b/src/runtime-rs/crates/hypervisor/src/qemu/cmdline_generator.rs
@@ -4,11 +4,12 @@
 //
 
 use crate::utils::clear_fd_flags;
-use crate::{kernel_param::KernelParams, HypervisorConfig};
+use crate::{kernel_param::KernelParams, HypervisorConfig, NetworkConfig};
 
 use anyhow::{anyhow, Context, Result};
 use async_trait::async_trait;
-use std::fs::read_to_string;
+use kata_types::config::hypervisor::NetworkInfo;
+use std::fs::{read_to_string, File};
 use std::os::unix::io::RawFd;
 
 // These should have been called MiB and GiB for better readability but the
@@ -846,6 +847,18 @@ impl<'a> QemuCmdLine<'a> {
         ));
     }
 
+    pub fn add_network_device(
+        &mut self,
+        _config: &NetworkConfig,
+        network_info: &NetworkInfo,
+    ) -> Result<Vec<File>> {
+        let _disable_vhost_net = network_info.disable_vhost_net;
+        let _queues = network_info.network_queues;
+        let fds: Vec<std::fs::File> = Vec::new();
+
+        Ok(fds)
+    }
+
     pub async fn build(&self) -> Result<Vec<String>> {
         let mut result = Vec::new();
 
diff --git a/src/runtime-rs/crates/hypervisor/src/qemu/inner.rs b/src/runtime-rs/crates/hypervisor/src/qemu/inner.rs
index b5614dd3c7..65bacc15c2 100644
--- a/src/runtime-rs/crates/hypervisor/src/qemu/inner.rs
+++ b/src/runtime-rs/crates/hypervisor/src/qemu/inner.rs
@@ -5,11 +5,12 @@
 
 use super::cmdline_generator::QemuCmdLine;
 use crate::{
-    hypervisor_persist::HypervisorState, HypervisorConfig, MemoryConfig, VcpuThreadIds,
-    VsockDevice, HYPERVISOR_QEMU,
+    hypervisor_persist::HypervisorState, utils::enter_netns, HypervisorConfig, MemoryConfig,
+    VcpuThreadIds, VsockDevice, HYPERVISOR_QEMU,
 };
 use anyhow::{anyhow, Context, Result};
 use async_trait::async_trait;
+use kata_sys_util::netns::NetnsGuard;
 use kata_types::{
     capabilities::{Capabilities, CapabilityBits},
     config::KATA_PATH,
@@ -68,6 +69,10 @@ impl QemuInner {
         // descriptor needs to stay open until the qemu process launches.
         // This is why we need to store it in a variable at this scope.
         let mut _vhost_fd = None;
+        // We need to keep the vhost-net/tuntap file descriptor open until the QEMU process launches.
+        // However, we're likely not interested in the specific type of file descriptor itself. We just
+        // want to ensure any fds associated with network devices remain open within the current scope.
+        let mut _fds_for_qemu: Vec<std::fs::File> = Vec::new();
 
         for device in &mut self.devices {
             match device {
@@ -102,6 +107,11 @@ impl QemuInner {
                         }
                     }
                 }
+                DeviceType::Network(network) => {
+                    let network_info = &self.config.network_info;
+
+                    _fds_for_qemu = cmdline.add_network_device(&network.config, network_info)?;
+                }
                 _ => info!(sl!(), "qemu cmdline: unsupported device: {:?}", device),
             }
         }