Add GetPossiblyMountedVolumesForPod to let kubelet know all volumes were unmounted

podVolumesExist() should consider also uncertain volumes (where kubelet
does not know if a volume was fully unmounted) when checking for pod's
volumes. Added GetPossiblyMountedVolumesForPod for that.

Adding uncertain mounts to GetMountedVolumesForPod would potentially break
other callers (e.g. `verifyVolumesMountedFunc`).

pkg/kubelet/kubelet_volumes.go

@@ -74,7 +74,7 @@ func (kl *Kubelet) ListBlockVolumesForPod(podUID types.UID) (map[string]volume.B
 // pods for the specified volume are mounted.
 func (kl *Kubelet) podVolumesExist(podUID types.UID) bool {
 	if mountedVolumes :=
-		kl.volumeManager.GetMountedVolumesForPod(
+		kl.volumeManager.GetPossiblyMountedVolumesForPod(
 			volumetypes.UniquePodName(podUID)); len(mountedVolumes) > 0 {
 		return true
 	}

pkg/kubelet/kubelet_volumes_test.go

@@ -397,6 +397,9 @@ func TestVolumeAttachAndMountControllerEnabled(t *testing.T) {
 
 	podVolumes := kubelet.volumeManager.GetMountedVolumesForPod(
 		util.GetUniquePodName(pod))
+	allPodVolumes := kubelet.volumeManager.GetPossiblyMountedVolumesForPod(
+		util.GetUniquePodName(pod))
+	assert.Equal(t, podVolumes, allPodVolumes, "GetMountedVolumesForPod and GetPossiblyMountedVolumesForPod should return the same volumes")
 
 	expectedPodVolumes := []string{"vol1"}
 	assert.Len(t, podVolumes, len(expectedPodVolumes), "Volumes for pod %+v", pod)
@@ -476,6 +479,9 @@ func TestVolumeUnmountAndDetachControllerEnabled(t *testing.T) {
 
 	podVolumes := kubelet.volumeManager.GetMountedVolumesForPod(
 		util.GetUniquePodName(pod))
+	allPodVolumes := kubelet.volumeManager.GetPossiblyMountedVolumesForPod(
+		util.GetUniquePodName(pod))
+	assert.Equal(t, podVolumes, allPodVolumes, "GetMountedVolumesForPod and GetPossiblyMountedVolumesForPod should return the same volumes")
 
 	expectedPodVolumes := []string{"vol1"}
 	assert.Len(t, podVolumes, len(expectedPodVolumes), "Volumes for pod %+v", pod)
@@ -500,6 +506,9 @@ func TestVolumeUnmountAndDetachControllerEnabled(t *testing.T) {
 	// Verify volumes unmounted
 	podVolumes = kubelet.volumeManager.GetMountedVolumesForPod(
 		util.GetUniquePodName(pod))
+	allPodVolumes = kubelet.volumeManager.GetPossiblyMountedVolumesForPod(
+		util.GetUniquePodName(pod))
+	assert.Equal(t, podVolumes, allPodVolumes, "GetMountedVolumesForPod and GetPossiblyMountedVolumesForPod should return the same volumes")
 
 	assert.Len(t, podVolumes, 0,
 		"Expected volumes to be unmounted and detached. But some volumes are still mounted: %#v", podVolumes)

pkg/kubelet/volumemanager/cache/actual_state_of_world.go

@@ -136,6 +136,11 @@ type ActualStateOfWorld interface {
 	// current actual state of the world.
 	GetMountedVolumesForPod(podName volumetypes.UniquePodName) []MountedVolume
 
+	// GetPossiblyMountedVolumesForPod generates and returns a list of volumes for
+	// the specified pod that either are attached and mounted or are "uncertain",
+	// i.e. a volume plugin may be mounting the volume right now.
+	GetPossiblyMountedVolumesForPod(podName volumetypes.UniquePodName) []MountedVolume
+
 	// GetGloballyMountedVolumes generates and returns a list of all attached
 	// volumes that are globally mounted. This list can be used to determine
 	// which volumes should be reported as "in use" in the node's VolumesInUse
@@ -757,6 +762,26 @@ func (asw *actualStateOfWorld) GetMountedVolumesForPod(
 	return mountedVolume
 }
 
+func (asw *actualStateOfWorld) GetPossiblyMountedVolumesForPod(
+	podName volumetypes.UniquePodName) []MountedVolume {
+	asw.RLock()
+	defer asw.RUnlock()
+	mountedVolume := make([]MountedVolume, 0 /* len */, len(asw.attachedVolumes) /* cap */)
+	for _, volumeObj := range asw.attachedVolumes {
+		for mountedPodName, podObj := range volumeObj.mountedPods {
+			if mountedPodName == podName &&
+				(podObj.volumeMountStateForPod == operationexecutor.VolumeMounted ||
+					podObj.volumeMountStateForPod == operationexecutor.VolumeMountUncertain) {
+				mountedVolume = append(
+					mountedVolume,
+					getMountedVolume(&podObj, &volumeObj))
+			}
+		}
+	}
+
+	return mountedVolume
+}
+
 func (asw *actualStateOfWorld) GetGloballyMountedVolumes() []AttachedVolume {
 	asw.RLock()
 	defer asw.RUnlock()

pkg/kubelet/volumemanager/cache/actual_state_of_world_test.go

@@ -20,7 +20,7 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/require"
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/kubernetes/pkg/volume"
 	volumetesting "k8s.io/kubernetes/pkg/volume/testing"
@@ -653,7 +653,18 @@ func TestUncertainVolumeMounts(t *testing.T) {
 		}
 	}
 	if volumeFound {
-		t.Fatalf("expected volume %s to be not found in asw", volumeSpec1.Name())
+		t.Fatalf("expected volume %s to be not found in asw.GetMountedVolumesForPod", volumeSpec1.Name())
+	}
+
+	possiblyMountedVolumes := asw.GetPossiblyMountedVolumesForPod(podName1)
+	volumeFound = false
+	for _, volume := range possiblyMountedVolumes {
+		if volume.InnerVolumeSpecName == volumeSpec1.Name() {
+			volumeFound = true
+		}
+	}
+	if !volumeFound {
+		t.Fatalf("expected volume %s to be found in aws.GetPossiblyMountedVolumesForPod", volumeSpec1.Name())
 	}
 
 	volExists, _, _ := asw.PodExistsInVolume(podName1, generatedVolumeName1)

pkg/kubelet/volumemanager/volume_manager.go

@@ -113,6 +113,14 @@ type VolumeManager interface {
 	// volumes.
 	GetMountedVolumesForPod(podName types.UniquePodName) container.VolumeMap
 
+	// GetPossiblyMountedVolumesForPod returns a VolumeMap containing the volumes
+	// referenced by the specified pod that are either successfully attached
+	// and mounted or are "uncertain", i.e. a volume plugin may be mounting
+	// them right now. The key in the map is the OuterVolumeSpecName (i.e.
+	// pod.Spec.Volumes[x].Name). It returns an empty VolumeMap if pod has no
+	// volumes.
+	GetPossiblyMountedVolumesForPod(podName types.UniquePodName) container.VolumeMap
+
 	// GetExtraSupplementalGroupsForPod returns a list of the extra
 	// supplemental groups for the Pod. These extra supplemental groups come
 	// from annotations on persistent volumes that the pod depends on.
@@ -290,6 +298,19 @@ func (vm *volumeManager) GetMountedVolumesForPod(podName types.UniquePodName) co
 	return podVolumes
 }
 
+func (vm *volumeManager) GetPossiblyMountedVolumesForPod(podName types.UniquePodName) container.VolumeMap {
+	podVolumes := make(container.VolumeMap)
+	for _, mountedVolume := range vm.actualStateOfWorld.GetPossiblyMountedVolumesForPod(podName) {
+		podVolumes[mountedVolume.OuterVolumeSpecName] = container.VolumeInfo{
+			Mounter:             mountedVolume.Mounter,
+			BlockVolumeMapper:   mountedVolume.BlockVolumeMapper,
+			ReadOnly:            mountedVolume.VolumeSpec.ReadOnly,
+			InnerVolumeSpecName: mountedVolume.InnerVolumeSpecName,
+		}
+	}
+	return podVolumes
+}
+
 func (vm *volumeManager) GetExtraSupplementalGroupsForPod(pod *v1.Pod) []int64 {
 	podName := util.GetUniquePodName(pod)
 	supplementalGroups := sets.NewString()

pkg/kubelet/volumemanager/volume_manager_fake.go

@@ -17,7 +17,7 @@ limitations under the License.
 package volumemanager
 
 import (
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	"k8s.io/kubernetes/pkg/kubelet/config"
 	"k8s.io/kubernetes/pkg/kubelet/container"
 	"k8s.io/kubernetes/pkg/volume/util/types"
@@ -55,6 +55,11 @@ func (f *FakeVolumeManager) GetMountedVolumesForPod(podName types.UniquePodName)
 	return nil
 }
 
+// GetPossiblyMountedVolumesForPod is not implemented
+func (f *FakeVolumeManager) GetPossiblyMountedVolumesForPod(podName types.UniquePodName) container.VolumeMap {
+	return nil
+}
+
 // GetExtraSupplementalGroupsForPod is not implemented
 func (f *FakeVolumeManager) GetExtraSupplementalGroupsForPod(pod *v1.Pod) []int64 {
 	return nil