qemu/qmp: implement function for hotplug network

Implement function to hotplug and delete a network device to QEMU

Signed-off-by: Ruidong Cao <caoruidong@huawei.com>

qemu/qmp.go

@@ -727,6 +727,51 @@ func (q *QMP) ExecuteBlockdevDel(ctx context.Context, blockdevID string) error {
 	return q.executeCommand(ctx, "x-blockdev-del", args, nil)
 }
 
+// ExecuteNetdevAdd adds a Net device to a QEMU instance
+// using the netdev_add command. netdevID is the id of the device to add.
+// Must be valid QMP identifier.
+func (q *QMP) ExecuteNetdevAdd(ctx context.Context, netdevType, netdevID, ifname, downscript, script string, queues int) error {
+	args := map[string]interface{}{
+		"type":       netdevType,
+		"id":         netdevID,
+		"ifname":     ifname,
+		"downscript": downscript,
+		"script":     script,
+	}
+	if queues > 1 {
+		args["queues"] = queues
+	}
+
+	return q.executeCommand(ctx, "netdev_add", args, nil)
+}
+
+// ExecuteNetdevDel deletes a Net device from a QEMU instance
+// using the netdev_del command. netdevID is the id of the device to delete.
+func (q *QMP) ExecuteNetdevDel(ctx context.Context, netdevID string) error {
+	args := map[string]interface{}{
+		"id": netdevID,
+	}
+	return q.executeCommand(ctx, "netdev_del", args, nil)
+}
+
+// ExecuteNetPCIDeviceAdd adds a Net PCI device to a QEMU instance
+// using the device_add command. devID is the id of the device to add.
+// Must be valid QMP identifier. netdevID is the id of nic added by previous netdev_add.
+func (q *QMP) ExecuteNetPCIDeviceAdd(ctx context.Context, netdevID, devID, macAddr, addr, bus string) error {
+	args := map[string]interface{}{
+		"id":     devID,
+		"driver": VirtioNetPCI,
+		"netdev": netdevID,
+		"mac":    macAddr,
+		"addr":   addr,
+	}
+
+	if bus != "" {
+		args["bus"] = bus
+	}
+	return q.executeCommand(ctx, "device_add", args, nil)
+}
+
 // ExecuteDeviceDel deletes guest portion of a QEMU device by sending a
 // device_del command.   devId is the identifier of the device to delete.
 // Typically it would match the devID parameter passed to an earlier call

qemu/qmp_test.go

@@ -364,6 +364,66 @@ func TestQMPBlockdevAdd(t *testing.T) {
 	<-disconnectedCh
 }
 
+// Checks that the netdev_add command is correctly sent.
+//
+// We start a QMPLoop, send the netdev_add command and stop the loop.
+//
+// The netdev_add command should be correctly sent and the QMP loop should
+// exit gracefully.
+func TestQMPNetdevAdd(t *testing.T) {
+	connectedCh := make(chan *QMPVersion)
+	disconnectedCh := make(chan struct{})
+	buf := newQMPTestCommandBuffer(t)
+	buf.AddCommand("netdev_add", nil, "return", nil)
+	cfg := QMPConfig{Logger: qmpTestLogger{}}
+	q := startQMPLoop(buf, cfg, connectedCh, disconnectedCh)
+	q.version = checkVersion(t, connectedCh)
+	err := q.ExecuteNetdevAdd(context.Background(), "tap", "br0", "tap0", "no", "no", 8)
+	if err != nil {
+		t.Fatalf("Unexpected error %v", err)
+	}
+	q.Shutdown()
+	<-disconnectedCh
+}
+
+// Checks that the netdev_del command is correctly sent.
+//
+// We start a QMPLoop, send the netdev_del command and stop the loop.
+//
+// The netdev_del command should be correctly sent and the QMP loop should
+// exit gracefully.
+func TestQMPNetdevDel(t *testing.T) {
+	connectedCh := make(chan *QMPVersion)
+	disconnectedCh := make(chan struct{})
+	buf := newQMPTestCommandBuffer(t)
+	buf.AddCommand("netdev_del", nil, "return", nil)
+	cfg := QMPConfig{Logger: qmpTestLogger{}}
+	q := startQMPLoop(buf, cfg, connectedCh, disconnectedCh)
+	q.version = checkVersion(t, connectedCh)
+	err := q.ExecuteNetdevDel(context.Background(), "br0")
+	if err != nil {
+		t.Fatalf("Unexpected error %v", err)
+	}
+	q.Shutdown()
+	<-disconnectedCh
+}
+
+func TestQMPNetPCIDeviceAdd(t *testing.T) {
+	connectedCh := make(chan *QMPVersion)
+	disconnectedCh := make(chan struct{})
+	buf := newQMPTestCommandBuffer(t)
+	buf.AddCommand("device_add", nil, "return", nil)
+	cfg := QMPConfig{Logger: qmpTestLogger{}}
+	q := startQMPLoop(buf, cfg, connectedCh, disconnectedCh)
+	checkVersion(t, connectedCh)
+	err := q.ExecuteNetPCIDeviceAdd(context.Background(), "br0", "virtio-0", "02:42:ac:11:00:02", "0x7", "")
+	if err != nil {
+		t.Fatalf("Unexpected error %v", err)
+	}
+	q.Shutdown()
+	<-disconnectedCh
+}
+
 // Checks that the device_add command is correctly sent.
 //
 // We start a QMPLoop, send the device_add command and stop the loop.