qmp: add ExecuteQueryMigration

It sends query-migrate qmp command to check migration status.

Signed-off-by: Peng Tao <bergwolf@gmail.com>

qemu/qmp.go

@@ -200,6 +200,46 @@ type CPUInfoFast struct {
 	Props    CPUProperties `json:"props"`
 }
 
+// MigrationRAM represents migration ram status
+type MigrationRAM struct {
+	Total            int64 `json:"total"`
+	Remaining        int64 `json:"remaining"`
+	Transferred      int64 `json:"transferred"`
+	TotalTime        int64 `json:"total-time"`
+	SetupTime        int64 `json:"setup-time"`
+	ExpectedDowntime int64 `json:"expected-downtime"`
+	Duplicate        int64 `json:"duplicate"`
+	Normal           int64 `json:"normal"`
+	NormalBytes      int64 `json:"normal-bytes"`
+	DirtySyncCount   int64 `json:"dirty-sync-count"`
+}
+
+// MigrationDisk represents migration disk status
+type MigrationDisk struct {
+	Total       int64 `json:"total"`
+	Remaining   int64 `json:"remaining"`
+	Transferred int64 `json:"transferred"`
+}
+
+// MigrationXbzrleCache represents migration XbzrleCache status
+type MigrationXbzrleCache struct {
+	CacheSize     int64 `json:"cache-size"`
+	Bytes         int64 `json:"bytes"`
+	Pages         int64 `json:"pages"`
+	CacheMiss     int64 `json:"cache-miss"`
+	CacheMissRate int64 `json:"cache-miss-rate"`
+	Overflow      int64 `json:"overflow"`
+}
+
+// MigrationStatus represents migration status of a vm
+type MigrationStatus struct {
+	Status       string                   `json:"status"`
+	Capabilities []map[string]interface{} `json:"capabilities,omitempty"`
+	RAM          MigrationRAM             `json:"ram,omitempty"`
+	Disk         MigrationDisk            `json:"disk,omitempty"`
+	XbzrleCache  MigrationXbzrleCache     `json:"xbzrle-cache,omitempty"`
+}
+
 func (q *QMP) readLoop(fromVMCh chan<- []byte) {
 	scanner := bufio.NewScanner(q.conn)
 	for scanner.Scan() {
@@ -1206,3 +1246,23 @@ func (q *QMP) ExecuteVirtSerialPortAdd(ctx context.Context, id, name, chardev st
 
 	return q.executeCommand(ctx, "device_add", args, nil)
 }
+
+// ExecuteQueryMigration queries migration progress.
+func (q *QMP) ExecuteQueryMigration(ctx context.Context) (MigrationStatus, error) {
+	response, err := q.executeCommandWithResponse(ctx, "query-migrate", nil, nil, nil)
+	if err != nil {
+		return MigrationStatus{}, err
+	}
+
+	data, err := json.Marshal(response)
+	if err != nil {
+		return MigrationStatus{}, fmt.Errorf("Unable to extract migrate status information: %v", err)
+	}
+
+	var status MigrationStatus
+	if err = json.Unmarshal(data, &status); err != nil {
+		return MigrationStatus{}, fmt.Errorf("Unable to convert migrate status information: %v", err)
+	}
+
+	return status, nil
+}

qemu/qmp_test.go

@@ -1295,3 +1295,53 @@ func TestExecuteVirtSerialPortAdd(t *testing.T) {
 	q.Shutdown()
 	<-disconnectedCh
 }
+
+// Checks migration status
+func TestExecuteQueryMigration(t *testing.T) {
+	connectedCh := make(chan *QMPVersion)
+	disconnectedCh := make(chan struct{})
+	buf := newQMPTestCommandBuffer(t)
+	status := MigrationStatus{
+		Status: "completed",
+		RAM: MigrationRAM{
+			Total:            100,
+			Remaining:        101,
+			Transferred:      101,
+			TotalTime:        101,
+			SetupTime:        101,
+			ExpectedDowntime: 101,
+			Duplicate:        101,
+			Normal:           101,
+			NormalBytes:      101,
+			DirtySyncCount:   101,
+		},
+		Disk: MigrationDisk{
+			Total:       200,
+			Remaining:   200,
+			Transferred: 200,
+		},
+		XbzrleCache: MigrationXbzrleCache{
+			CacheSize:     300,
+			Bytes:         300,
+			Pages:         300,
+			CacheMiss:     300,
+			CacheMissRate: 300,
+			Overflow:      300,
+		},
+	}
+	caps := map[string]interface{}{"foo": true}
+	status.Capabilities = append(status.Capabilities, caps)
+	buf.AddCommand("query-migrate", nil, "return", interface{}(status))
+	cfg := QMPConfig{Logger: qmpTestLogger{}}
+	q := startQMPLoop(buf, cfg, connectedCh, disconnectedCh)
+	checkVersion(t, connectedCh)
+	s, err := q.ExecuteQueryMigration(context.Background())
+	if err != nil {
+		t.Fatalf("Unexpected error %v", err)
+	}
+	if !reflect.DeepEqual(s, status) {
+		t.Fatalf("expected %v\n got %v", status, s)
+	}
+	q.Shutdown()
+	<-disconnectedCh
+}