if opts.CheckPrecondFn != nil {
		if !opts.NoLock {
			ns := er.NewNSLock(bucket, object)
			lkctx, err := ns.GetLock(ctx, globalOperationTimeout)
			if err != nil {
				return nil, err
			}
			ctx = lkctx.Context()
			defer ns.Unlock(lkctx)
			opts.NoLock = true
		}

		obj, err := er.getObjectInfo(ctx, bucket, object, opts)

			if idx := strings.IndexByte(forward, '/'); idx > 0 {
				forward = forward[:idx]
			}
		}

		if s.walkMu != nil {
			s.walkMu.Lock()
		}
		entries, err := s.ListDir(ctx, "", opts.Bucket, current, -1)
		if s.walkMu != nil {
			s.walkMu.Unlock()
		}
		if err != nil {
			// Folder could have gone away in-between
			if err != errVolumeNotFound && err != errFileNotFound {

	// Wait for messages to be sent...
	h.wg.Wait()

	// Set logch to nil and close it.
	// This will block all Send operations,
	// and finish the existing ones.
	// All future ones will be discarded.
	h.logChMu.Lock()
	xioutil.SafeClose(h.logCh)
	h.logCh = nil
	h.logChMu.Unlock()

	lock := api.NewNSLock(r.Bucket, objInfo.Name)
	lkctx, err := lock.GetLock(ctx, globalOperationTimeout)
	if err != nil {
		return err
	}
	ctx = lkctx.Context()
	defer lock.Unlock(lkctx)

	opts := ObjectOptions{
		VersionID:        objInfo.VersionID,
		Versioned:        versioned,
		VersionSuspended: versionSuspended,
		NoLock:           true,
	}

	rl = wl.DRLocker()
	n := 10
	go func() {
		for range n {
			rl.Lock()
			rl.Lock()
			rlocked <- true
			wl.Lock()
			wlocked <- true
		}
	}()
	for range n {
		<-rlocked
		rl.Unlock()
		select {
		case <-wlocked:
			t.Fatal("RLocker() didn't read-lock it")
		default:
		}
		rl.Unlock()
		<-wlocked
		select {
		case <-rlocked:

type NetLocker interface {
	// Do read lock for given LockArgs.  It should return
	// * a boolean to indicate success/failure of the operation
	// * an error on failure of lock request operation.
	RLock(ctx context.Context, args LockArgs) (bool, error)

	// Do write lock for given LockArgs. It should return
	// * a boolean to indicate success/failure of the operation
	// * an error on failure of lock request operation.

					return ObjectLocked{}
				}

				if !ret.RetainUntilDate.Before(t) {
					return ObjectLocked{}
				}
				return nil
			}
			// https://docs.aws.amazon.com/AmazonS3/latest/dev/object-lock-overview.html#object-lock-retention-modes
			// If you try to delete objects protected by governance mode and have s3:BypassGovernanceRetention, the operation will succeed.

	dm.Unlock(t.Context())

	dm.Lock(id, source)
	time.Sleep(time.Duration(10+(rand.Float32()*50)) * time.Millisecond)
	dm.Unlock(t.Context())

	dm.Lock(id, source)
	time.Sleep(time.Duration(10+(rand.Float32()*50)) * time.Millisecond)
	dm.Unlock(t.Context())

	dm.Lock(id, source)
	time.Sleep(time.Duration(10+(rand.Float32()*50)) * time.Millisecond)
	dm.Unlock(t.Context())
}

	}

	l.mutex.Lock()
	defer l.mutex.Unlock()
	var locksHeld int64
	if locksHeld, reply = l.lockMap[args.Resources[0]]; !reply { // No lock is held on the given name
		return false, fmt.Errorf("Unlock attempted on an unlocked entity: %s", args.Resources[0])
	}
	if reply = locksHeld == WriteLock; !reply { // Unless it is a write lock

func resetGlobalObjectAPI() {
	globalObjLayerMutex.Lock()
	globalObjectAPI = nil
	globalObjLayerMutex.Unlock()
}

// reset the value of the Global server config.
// set it to `nil`.
func resetGlobalConfig() {
	// hold the mutex lock before a new config is assigned.
	globalServerConfigMu.Lock()
	// Save the loaded config globally.
	globalServerConfig = nil
	globalServerConfigMu.Unlock()
}

func resetGlobalEndpoints() {