Merge pull request #44785 from jingxu97/April/apistorage

Automatic merge from submit-queue

Add Local Storage Capacity Isolation API

This PR adds the new APIs to support storage capacity isolation as
described in the proposal [https://github.com/kubernetes/community/pull/306](url)

1. Add SizeLimit for emptyDir volume
2. Add scratch and overlay storage type used by container level or
node level


**Release note**:

```release-note
Alpha feature: Local volume Storage Capacity Isolation allows users to set storage limit to isolate EmptyDir volumes, container storage overlay, and also supports allocatable storage for shared root file system. 
```

pkg/api/validation/validation.go

@@ -398,7 +398,12 @@ func validateVolumeSource(source *api.VolumeSource, fldPath *field.Path) field.E
 	allErrs := field.ErrorList{}
 	if source.EmptyDir != nil {
 		numVolumes++
-		// EmptyDirs have nothing to validate
+		if !utilfeature.DefaultFeatureGate.Enabled(features.LocalStorageCapacityIsolation) {
+			unsetSizeLimit := resource.Quantity{}
+			if unsetSizeLimit.Cmp(source.EmptyDir.SizeLimit) != 0 {
+				allErrs = append(allErrs, field.Forbidden(fldPath.Child("emptyDir").Child("sizeLimit"), "SizeLimit field disabled by feature-gate for EmptyDir volumes"))
+			}
+		}
 	}
 	if source.HostPath != nil {
 		if numVolumes > 0 {
@@ -3638,6 +3643,9 @@ func ValidateResourceRequirements(requirements *api.ResourceRequirements, fldPat
 				allErrs = append(allErrs, field.Invalid(limPath, quantity.String(), fmt.Sprintf("must be greater than or equal to %s request", resourceName)))
 			}
 		}
+		if resourceName == api.ResourceStorageOverlay && !utilfeature.DefaultFeatureGate.Enabled(features.LocalStorageCapacityIsolation) {
+			allErrs = append(allErrs, field.Forbidden(limPath, "ResourceStorageOverlay field disabled by feature-gate for ResourceRequirements"))
+		}
 	}
 	for resourceName, quantity := range requirements.Requests {
 		fldPath := reqPath.Key(string(resourceName))