From cda04fa5392730aef446f7edc9427f9ae2a6a347 Mon Sep 17 00:00:00 2001
From: Pavel Mores <pmores@redhat.com>
Date: Thu, 15 Aug 2024 11:41:36 +0200
Subject: [PATCH] runtime-rs: factor setup of network device out of QemuCmdLine

Network device hotplugging will use the same infrastructure (Netdev,
DeviceVirtioNet) as coldplugging, i.e. QemuCmdLine.  To make the code
of network device setup visible outside of QemuCmdLine we factor it out
to a non-member function `get_network_device()` and make QemuCmdLine just
delegate to it.

Signed-off-by: Pavel Mores <pmores@redhat.com>
---
 .../hypervisor/src/qemu/cmdline_generator.rs  | 56 +++++++++++--------
 1 file changed, 33 insertions(+), 23 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 3abb990095..484c0630b2 100644
--- a/src/runtime-rs/crates/hypervisor/src/qemu/cmdline_generator.rs
+++ b/src/runtime-rs/crates/hypervisor/src/qemu/cmdline_generator.rs
@@ -983,7 +983,7 @@ fn format_fds(files: &[File]) -> String {
 }
 
 #[derive(Debug)]
-struct Netdev {
+pub struct Netdev {
     id: String,
 
     // File descriptors for vhost multi-queue support.
@@ -1723,28 +1723,8 @@ impl<'a> QemuCmdLine<'a> {
         host_dev_name: &str,
         guest_mac: Address,
     ) -> Result<()> {
-        let mut netdev = Netdev::new(
-            &format!("network-{}", dev_index),
-            host_dev_name,
-            self.config.network_info.network_queues,
-        )?;
-        if self.config.network_info.disable_vhost_net {
-            netdev.set_disable_vhost_net(true);
-        }
-
-        let mut virtio_net_device = DeviceVirtioNet::new(&netdev.id, guest_mac);
-
-        if should_disable_modern() {
-            virtio_net_device.set_disable_modern(true);
-        }
-        if self.config.device_info.enable_iommu_platform
-            && bus_type(self.config) == VirtioBusType::Ccw
-        {
-            virtio_net_device.set_iommu_platform(true);
-        }
-        if self.config.network_info.network_queues > 1 {
-            virtio_net_device.set_num_queues(self.config.network_info.network_queues);
-        }
+        let (netdev, virtio_net_device) =
+            get_network_device(self.config, dev_index, host_dev_name, guest_mac)?;
 
         self.devices.push(Box::new(netdev));
         self.devices.push(Box::new(virtio_net_device));
@@ -1796,3 +1776,33 @@ impl<'a> QemuCmdLine<'a> {
         Ok(result)
     }
 }
+
+pub fn get_network_device(
+    config: &HypervisorConfig,
+    dev_index: u64,
+    host_dev_name: &str,
+    guest_mac: Address,
+) -> Result<(Netdev, DeviceVirtioNet)> {
+    let mut netdev = Netdev::new(
+        &format!("network-{}", dev_index),
+        host_dev_name,
+        config.network_info.network_queues,
+    )?;
+    if config.network_info.disable_vhost_net {
+        netdev.set_disable_vhost_net(true);
+    }
+
+    let mut virtio_net_device = DeviceVirtioNet::new(&netdev.id, guest_mac);
+
+    if should_disable_modern() {
+        virtio_net_device.set_disable_modern(true);
+    }
+    if config.device_info.enable_iommu_platform && bus_type(config) == VirtioBusType::Ccw {
+        virtio_net_device.set_iommu_platform(true);
+    }
+    if config.network_info.network_queues > 1 {
+        virtio_net_device.set_num_queues(config.network_info.network_queues);
+    }
+
+    Ok((netdev, virtio_net_device))
+}