Add explicit warning for deprecation of Cinder and ScaleIO volume pro…

…viders

We have had a warning for OpenStack in-tree cloud provider, Here we are
adding more fine grained WARNING for OpenStack cinder volume provider in
addition to that.

Also identified ScaleIO as something that has not had activity or
updates for a while, So we should deprecate that as well

pkg/volume/plugins.go

@@ -66,6 +66,13 @@ const (
 	CSIVolumePublished CSIVolumePhaseType = "published"
 )
 
+var (
+	deprecatedVolumeProviders = map[string]string{
+		"kubernetes.io/cinder":  "The Cinder volume provider is deprecated and will be removed in a future release",
+		"kubernetes.io/scaleio": "The ScaleIO volume provider is deprecated and will be removed in a future release",
+	}
+)
+
 // VolumeOptions contains option information about a volume.
 type VolumeOptions struct {
 	// The attributes below are required by volume.Provisioner
@@ -674,6 +681,11 @@ func (pm *VolumePluginMgr) FindPluginBySpec(spec *Spec) (VolumePlugin, error) {
 		}
 		return nil, fmt.Errorf("multiple volume plugins matched: %s", strings.Join(matchedPluginNames, ","))
 	}
+
+	// Issue warning if the matched provider is deprecated
+	if detail, ok := deprecatedVolumeProviders[matches[0].GetPluginName()]; ok {
+		klog.Warningf("WARNING: %s built-in volume provider is now deprecated. %s", matches[0].GetPluginName(), detail)
+	}
 	return matches[0], nil
 }
 
@@ -737,6 +749,11 @@ func (pm *VolumePluginMgr) FindPluginByName(name string) (VolumePlugin, error) {
 		}
 		return nil, fmt.Errorf("multiple volume plugins matched: %s", strings.Join(matchedPluginNames, ","))
 	}
+
+	// Issue warning if the matched provider is deprecated
+	if detail, ok := deprecatedVolumeProviders[matches[0].GetPluginName()]; ok {
+		klog.Warningf("WARNING: %s built-in volume provider is now deprecated. %s", matches[0].GetPluginName(), detail)
+	}
 	return matches[0], nil
 }