Merge pull request #49727 from gnufied/expand-pvc-plugin-changes

api/openapi-spec/swagger.json

@@ -65753,6 +65753,37 @@
      }
     ]
    },
+   "io.k8s.api.core.v1.PersistentVolumeClaimCondition": {
+    "description": "PersistentVolumeClaimCondition contails details about state of pvc",
+    "required": [
+     "type",
+     "status"
+    ],
+    "properties": {
+     "lastProbeTime": {
+      "description": "Last time we probed the condition.",
+      "$ref": "#/definitions/io.k8s.apimachinery.pkg.apis.meta.v1.Time"
+     },
+     "lastTransitionTime": {
+      "description": "Last time the condition transitioned from one status to another.",
+      "$ref": "#/definitions/io.k8s.apimachinery.pkg.apis.meta.v1.Time"
+     },
+     "message": {
+      "description": "Human-readable message indicating details about last transition.",
+      "type": "string"
+     },
+     "reason": {
+      "description": "Unique, this should be a short, machine understandable string that gives the reason for condition's last transition. If it reports \"ResizeStarted\" that means the underlying persistent volume is being resized.",
+      "type": "string"
+     },
+     "status": {
+      "type": "string"
+     },
+     "type": {
+      "type": "string"
+     }
+    }
+   },
    "io.k8s.api.core.v1.PersistentVolumeClaimList": {
     "description": "PersistentVolumeClaimList is a list of PersistentVolumeClaim items.",
     "required": [
@@ -65832,6 +65863,15 @@
        "$ref": "#/definitions/io.k8s.apimachinery.pkg.api.resource.Quantity"
       }
      },
+     "conditions": {
+      "description": "Current Condition of persistent volume claim. If underlying persistent volume is being resized then the Condition will be set to 'ResizeStarted'.",
+      "type": "array",
+      "items": {
+       "$ref": "#/definitions/io.k8s.api.core.v1.PersistentVolumeClaimCondition"
+      },
+      "x-kubernetes-patch-merge-key": "type",
+      "x-kubernetes-patch-strategy": "merge"
+     },
      "phase": {
       "description": "Phase represents the current phase of PersistentVolumeClaim.",
       "type": "string"
@@ -70708,6 +70748,10 @@
      "provisioner"
     ],
     "properties": {
+     "allowVolumeExpansion": {
+      "description": "AllowVolumeExpansion shows whether the storage class allow volume expand",
+      "type": "boolean"
+     },
      "apiVersion": {
       "description": "APIVersion defines the versioned schema of this representation of an object. Servers should convert recognized schemas to the latest internal value, and may reject unrecognized values. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#resources",
       "type": "string"
@@ -70791,6 +70835,10 @@
      "provisioner"
     ],
     "properties": {
+     "allowVolumeExpansion": {
+      "description": "AllowVolumeExpansion shows whether the storage class allow volume expand",
+      "type": "boolean"
+     },
      "apiVersion": {
       "description": "APIVersion defines the versioned schema of this representation of an object. Servers should convert recognized schemas to the latest internal value, and may reject unrecognized values. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#resources",
       "type": "string"

api/swagger-spec/apps_v1beta1.json

@@ -6524,6 +6524,45 @@
      "capacity": {
       "type": "object",
       "description": "Represents the actual resources of the underlying volume."
+     },
+     "conditions": {
+      "type": "array",
+      "items": {
+       "$ref": "v1.PersistentVolumeClaimCondition"
+      },
+      "description": "Current Condition of persistent volume claim. If underlying persistent volume is being resized then the Condition will be set to 'ResizeStarted'."
+     }
+    }
+   },
+   "v1.PersistentVolumeClaimCondition": {
+    "id": "v1.PersistentVolumeClaimCondition",
+    "description": "PersistentVolumeClaimCondition contails details about state of pvc",
+    "required": [
+     "type",
+     "status"
+    ],
+    "properties": {
+     "type": {
+      "type": "string"
+     },
+     "status": {
+      "type": "string"
+     },
+     "lastProbeTime": {
+      "type": "string",
+      "description": "Last time we probed the condition."
+     },
+     "lastTransitionTime": {
+      "type": "string",
+      "description": "Last time the condition transitioned from one status to another."
+     },
+     "reason": {
+      "type": "string",
+      "description": "Unique, this should be a short, machine understandable string that gives the reason for condition's last transition. If it reports \"ResizeStarted\" that means the underlying persistent volume is being resized."
+     },
+     "message": {
+      "type": "string",
+      "description": "Human-readable message indicating details about last transition."
      }
     }
    },

api/swagger-spec/apps_v1beta2.json

@@ -9142,6 +9142,45 @@
      "capacity": {
       "type": "object",
       "description": "Represents the actual resources of the underlying volume."
+     },
+     "conditions": {
+      "type": "array",
+      "items": {
+       "$ref": "v1.PersistentVolumeClaimCondition"
+      },
+      "description": "Current Condition of persistent volume claim. If underlying persistent volume is being resized then the Condition will be set to 'ResizeStarted'."
+     }
+    }
+   },
+   "v1.PersistentVolumeClaimCondition": {
+    "id": "v1.PersistentVolumeClaimCondition",
+    "description": "PersistentVolumeClaimCondition contails details about state of pvc",
+    "required": [
+     "type",
+     "status"
+    ],
+    "properties": {
+     "type": {
+      "type": "string"
+     },
+     "status": {
+      "type": "string"
+     },
+     "lastProbeTime": {
+      "type": "string",
+      "description": "Last time we probed the condition."
+     },
+     "lastTransitionTime": {
+      "type": "string",
+      "description": "Last time the condition transitioned from one status to another."
+     },
+     "reason": {
+      "type": "string",
+      "description": "Unique, this should be a short, machine understandable string that gives the reason for condition's last transition. If it reports \"ResizeStarted\" that means the underlying persistent volume is being resized."
+     },
+     "message": {
+      "type": "string",
+      "description": "Human-readable message indicating details about last transition."
      }
     }
    },

api/swagger-spec/storage.k8s.io_v1.json

@@ -795,6 +795,10 @@
        "type": "string"
       },
       "description": "Dynamically provisioned PersistentVolumes of this storage class are created with these mountOptions, e.g. [\"ro\", \"soft\"]. Not validated - mount of the PVs will simply fail if one is invalid."
+     },
+     "allowVolumeExpansion": {
+      "type": "boolean",
+      "description": "AllowVolumeExpansion shows whether the storage class allow volume expand"
      }
     }
    },

api/swagger-spec/storage.k8s.io_v1beta1.json

@@ -795,6 +795,10 @@
        "type": "string"
       },
       "description": "Dynamically provisioned PersistentVolumes of this storage class are created with these mountOptions, e.g. [\"ro\", \"soft\"]. Not validated - mount of the PVs will simply fail if one is invalid."
+     },
+     "allowVolumeExpansion": {
+      "type": "boolean",
+      "description": "AllowVolumeExpansion shows whether the storage class allow volume expand"
      }
     }
    },

api/swagger-spec/v1.json

@@ -20099,6 +20099,45 @@
      "capacity": {
       "type": "object",
       "description": "Represents the actual resources of the underlying volume."
+     },
+     "conditions": {
+      "type": "array",
+      "items": {
+       "$ref": "v1.PersistentVolumeClaimCondition"
+      },
+      "description": "Current Condition of persistent volume claim. If underlying persistent volume is being resized then the Condition will be set to 'ResizeStarted'."
+     }
+    }
+   },
+   "v1.PersistentVolumeClaimCondition": {
+    "id": "v1.PersistentVolumeClaimCondition",
+    "description": "PersistentVolumeClaimCondition contails details about state of pvc",
+    "required": [
+     "type",
+     "status"
+    ],
+    "properties": {
+     "type": {
+      "type": "string"
+     },
+     "status": {
+      "type": "string"
+     },
+     "lastProbeTime": {
+      "type": "string",
+      "description": "Last time we probed the condition."
+     },
+     "lastTransitionTime": {
+      "type": "string",
+      "description": "Last time the condition transitioned from one status to another."
+     },
+     "reason": {
+      "type": "string",
+      "description": "Unique, this should be a short, machine understandable string that gives the reason for condition's last transition. If it reports \"ResizeStarted\" that means the underlying persistent volume is being resized."
+     },
+     "message": {
+      "type": "string",
+      "description": "Human-readable message indicating details about last transition."
      }
     }
    },

cmd/kube-apiserver/app/options/BUILD

@@ -37,6 +37,7 @@ go_library(
         "//plugin/pkg/admission/namespace/exists:go_default_library",
         "//plugin/pkg/admission/noderestriction:go_default_library",
         "//plugin/pkg/admission/persistentvolume/label:go_default_library",
+        "//plugin/pkg/admission/persistentvolume/resize:go_default_library",
         "//plugin/pkg/admission/podnodeselector:go_default_library",
         "//plugin/pkg/admission/podpreset:go_default_library",
         "//plugin/pkg/admission/podtolerationrestriction:go_default_library",

cmd/kube-apiserver/app/options/plugins.go

@@ -41,6 +41,7 @@ import (
 	"k8s.io/kubernetes/plugin/pkg/admission/namespace/exists"
 	"k8s.io/kubernetes/plugin/pkg/admission/noderestriction"
 	"k8s.io/kubernetes/plugin/pkg/admission/persistentvolume/label"
+	"k8s.io/kubernetes/plugin/pkg/admission/persistentvolume/resize"
 	"k8s.io/kubernetes/plugin/pkg/admission/podnodeselector"
 	"k8s.io/kubernetes/plugin/pkg/admission/podpreset"
 	"k8s.io/kubernetes/plugin/pkg/admission/podtolerationrestriction"
@@ -81,4 +82,5 @@ func RegisterAllAdmissionPlugins(plugins *admission.Plugins) {
 	serviceaccount.Register(plugins)
 	setdefault.Register(plugins)
 	webhook.Register(plugins)
+	resize.Register(plugins)
 }

cmd/kube-controller-manager/app/BUILD

@@ -72,6 +72,7 @@ go_library(
         "//pkg/controller/statefulset:go_default_library",
         "//pkg/controller/ttl:go_default_library",
         "//pkg/controller/volume/attachdetach:go_default_library",
+        "//pkg/controller/volume/expand:go_default_library",
         "//pkg/controller/volume/persistentvolume:go_default_library",
         "//pkg/features:go_default_library",
         "//pkg/quota/install:go_default_library",

cmd/kube-controller-manager/app/controllermanager.go

@@ -357,6 +357,7 @@ func NewControllerInitializers() map[string]InitFunc {
 	controllers["route"] = startRouteController
 	controllers["persistentvolume-binder"] = startPersistentVolumeBinderController
 	controllers["attachdetach"] = startAttachDetachController
+	controllers["persistentvolume-expander"] = startVolumeExpandController
 
 	return controllers
 }

cmd/kube-controller-manager/app/core.go

@@ -51,6 +51,7 @@ import (
 	serviceaccountcontroller "k8s.io/kubernetes/pkg/controller/serviceaccount"
 	ttlcontroller "k8s.io/kubernetes/pkg/controller/ttl"
 	"k8s.io/kubernetes/pkg/controller/volume/attachdetach"
+	"k8s.io/kubernetes/pkg/controller/volume/expand"
 	persistentvolumecontroller "k8s.io/kubernetes/pkg/controller/volume/persistentvolume"
 	"k8s.io/kubernetes/pkg/features"
 	quotainstall "k8s.io/kubernetes/pkg/quota/install"
@@ -189,6 +190,24 @@ func startAttachDetachController(ctx ControllerContext) (bool, error) {
 	return true, nil
 }
 
+func startVolumeExpandController(ctx ControllerContext) (bool, error) {
+	if utilfeature.DefaultFeatureGate.Enabled(features.ExpandPersistentVolumes) {
+		expandController, expandControllerErr := expand.NewExpandController(
+			ctx.ClientBuilder.ClientOrDie("expand-controller"),
+			ctx.InformerFactory.Core().V1().PersistentVolumeClaims(),
+			ctx.InformerFactory.Core().V1().PersistentVolumes(),
+			ctx.Cloud,
+			ProbeExpandableVolumePlugins(ctx.Options.VolumeConfiguration))
+
+		if expandControllerErr != nil {
+			return true, fmt.Errorf("Failed to start volume expand controller : %v", expandControllerErr)
+		}
+		go expandController.Run(ctx.Stop)
+		return true, nil
+	}
+	return false, nil
+}
+
 func startEndpointController(ctx ControllerContext) (bool, error) {
 	go endpointcontroller.NewEndpointController(
 		ctx.InformerFactory.Core().V1().Pods(),

cmd/kube-controller-manager/app/plugins.go

@@ -88,6 +88,25 @@ func GetDynamicPluginProber(config componentconfig.VolumeConfiguration) volume.D
 	return flexvolume.GetDynamicPluginProber(config.FlexVolumePluginDir)
 }
 
+// ProbeExpandableVolumePlugins returns volume plugins which are expandable
+func ProbeExpandableVolumePlugins(config componentconfig.VolumeConfiguration) []volume.VolumePlugin {
+	allPlugins := []volume.VolumePlugin{}
+
+	allPlugins = append(allPlugins, aws_ebs.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, gce_pd.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, cinder.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, portworx.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, vsphere_volume.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, glusterfs.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, rbd.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, azure_dd.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, photon_pd.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, scaleio.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, storageos.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, fc.ProbeVolumePlugins()...)
+	return allPlugins
+}
+
 // ProbeControllerVolumePlugins collects all persistent volume plugins into an
 // easy to use list. Only volume plugins that implement any of
 // provisioner/recycler/deleter interface should be returned.

docs/api-reference/apps/v1beta1/definitions.html

@@ -2482,6 +2482,13 @@ When an object is created, the system will populate this list with the current s
 <td class="tableblock halign-left valign-top"><p class="tableblock">object</p></td>
 <td class="tableblock halign-left valign-top"></td>
 </tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">conditions</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">Current Condition of persistent volume claim. If underlying persistent volume is being resized then the Condition will be set to <em>ResizeStarted</em>.</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock"><a href="#_v1_persistentvolumeclaimcondition">v1.PersistentVolumeClaimCondition</a> array</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
 </tbody>
 </table>
 
@@ -2521,6 +2528,75 @@ When an object is created, the system will populate this list with the current s
 
 </div>
 <div class="sect2">
+<h3 id="_v1_persistentvolumeclaimcondition">v1.PersistentVolumeClaimCondition</h3>
+<div class="paragraph">
+<p>PersistentVolumeClaimCondition contails details about state of pvc</p>
+</div>
+<table class="tableblock frame-all grid-all" style="width:100%; ">
+<colgroup>
+<col style="width:20%;">
+<col style="width:20%;">
+<col style="width:20%;">
+<col style="width:20%;">
+<col style="width:20%;"> 
+</colgroup>
+<thead>
+<tr>
+<th class="tableblock halign-left valign-top">Name</th>
+<th class="tableblock halign-left valign-top">Description</th>
+<th class="tableblock halign-left valign-top">Required</th>
+<th class="tableblock halign-left valign-top">Schema</th>
+<th class="tableblock halign-left valign-top">Default</th>
+</tr>
+</thead>
+<tbody>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">type</p></td>
+<td class="tableblock halign-left valign-top"></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">true</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">status</p></td>
+<td class="tableblock halign-left valign-top"></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">true</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">lastProbeTime</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">Last time we probed the condition.</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">lastTransitionTime</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">Last time the condition transitioned from one status to another.</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">reason</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">Unique, this should be a short, machine understandable string that gives the reason for condition&#8217;s last transition. If it reports "ResizeStarted" that means the underlying persistent volume is being resized.</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">message</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">Human-readable message indicating details about last transition.</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+</tbody>
+</table>
+
+</div>
+<div class="sect2">
 <h3 id="_v1_secretvolumesource">v1.SecretVolumeSource</h3>
 <div class="paragraph">
 <p>Adapts a Secret into a volume.</p>

docs/api-reference/apps/v1beta2/definitions.html

@@ -2808,6 +2808,13 @@ When an object is created, the system will populate this list with the current s
 <td class="tableblock halign-left valign-top"><p class="tableblock">object</p></td>
 <td class="tableblock halign-left valign-top"></td>
 </tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">conditions</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">Current Condition of persistent volume claim. If underlying persistent volume is being resized then the Condition will be set to <em>ResizeStarted</em>.</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock"><a href="#_v1_persistentvolumeclaimcondition">v1.PersistentVolumeClaimCondition</a> array</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
 </tbody>
 </table>
 
@@ -3096,6 +3103,75 @@ When an object is created, the system will populate this list with the current s
 
 </div>
 <div class="sect2">
+<h3 id="_v1_persistentvolumeclaimcondition">v1.PersistentVolumeClaimCondition</h3>
+<div class="paragraph">
+<p>PersistentVolumeClaimCondition contails details about state of pvc</p>
+</div>
+<table class="tableblock frame-all grid-all" style="width:100%; ">
+<colgroup>
+<col style="width:20%;">
+<col style="width:20%;">
+<col style="width:20%;">
+<col style="width:20%;">
+<col style="width:20%;"> 
+</colgroup>
+<thead>
+<tr>
+<th class="tableblock halign-left valign-top">Name</th>
+<th class="tableblock halign-left valign-top">Description</th>
+<th class="tableblock halign-left valign-top">Required</th>
+<th class="tableblock halign-left valign-top">Schema</th>
+<th class="tableblock halign-left valign-top">Default</th>
+</tr>
+</thead>
+<tbody>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">type</p></td>
+<td class="tableblock halign-left valign-top"></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">true</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">status</p></td>
+<td class="tableblock halign-left valign-top"></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">true</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">lastProbeTime</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">Last time we probed the condition.</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">lastTransitionTime</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">Last time the condition transitioned from one status to another.</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">reason</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">Unique, this should be a short, machine understandable string that gives the reason for condition&#8217;s last transition. If it reports "ResizeStarted" that means the underlying persistent volume is being resized.</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">message</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">Human-readable message indicating details about last transition.</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">string</p></td>
+<td class="tableblock halign-left valign-top"></td>
+</tr>
+</tbody>
+</table>
+
+</div>
+<div class="sect2">
 <h3 id="_v1_secretvolumesource">v1.SecretVolumeSource</h3>
 <div class="paragraph">
 <p>Adapts a Secret into a volume.</p>

docs/api-reference/storage.k8s.io/v1/definitions.html

@@ -989,6 +989,13 @@ span.icon > [class^="icon-"], span.icon > [class*=" icon-"] { cursor: default; }
 <td class="tableblock halign-left valign-top"><p class="tableblock">string array</p></td>
 <td class="tableblock halign-left valign-top"></td>
 </tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">allowVolumeExpansion</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">AllowVolumeExpansion shows whether the storage class allow volume expand</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">boolean</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+</tr>
 </tbody>
 </table>
 

docs/api-reference/storage.k8s.io/v1beta1/definitions.html

@@ -951,6 +951,13 @@ span.icon > [class^="icon-"], span.icon > [class*=" icon-"] { cursor: default; }
 <td class="tableblock halign-left valign-top"><p class="tableblock">string array</p></td>
 <td class="tableblock halign-left valign-top"></td>
 </tr>
+<tr>
+<td class="tableblock halign-left valign-top"><p class="tableblock">allowVolumeExpansion</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">AllowVolumeExpansion shows whether the storage class allow volume expand</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">boolean</p></td>
+<td class="tableblock halign-left valign-top"><p class="tableblock">false</p></td>
+</tr>
 </tbody>
 </table>
 

hack/.golint_failures

@@ -190,6 +190,7 @@ pkg/controller/volume/attachdetach
 pkg/controller/volume/attachdetach/statusupdater
 pkg/controller/volume/attachdetach/testing
 pkg/controller/volume/events
+pkg/controller/volume/expand
 pkg/controller/volume/persistentvolume
 pkg/controller/volume/persistentvolume/options
 pkg/credentialprovider

pkg/api/types.go

@@ -547,6 +547,27 @@ type PersistentVolumeClaimSpec struct {
 	StorageClassName *string
 }
 
+type PersistentVolumeClaimConditionType string
+
+// These are valid conditions of Pvc
+const (
+	// An user trigger resize of pvc has been started
+	PersistentVolumeClaimResizing PersistentVolumeClaimConditionType = "Resizing"
+)
+
+type PersistentVolumeClaimCondition struct {
+	Type   PersistentVolumeClaimConditionType
+	Status ConditionStatus
+	// +optional
+	LastProbeTime metav1.Time
+	// +optional
+	LastTransitionTime metav1.Time
+	// +optional
+	Reason string
+	// +optional
+	Message string
+}
+
 type PersistentVolumeClaimStatus struct {
 	// Phase represents the current phase of PersistentVolumeClaim
 	// +optional
@@ -557,6 +578,8 @@ type PersistentVolumeClaimStatus struct {
 	// Represents the actual resources of the underlying volume
 	// +optional
 	Capacity ResourceList
+	// +optional
+	Conditions []PersistentVolumeClaimCondition
 }
 
 type PersistentVolumeAccessMode string

pkg/api/v1/zz_generated.conversion.go

@@ -233,6 +233,8 @@ func RegisterConversions(scheme *runtime.Scheme) error {
 		Convert_api_PersistentVolume_To_v1_PersistentVolume,
 		Convert_v1_PersistentVolumeClaim_To_api_PersistentVolumeClaim,
 		Convert_api_PersistentVolumeClaim_To_v1_PersistentVolumeClaim,
+		Convert_v1_PersistentVolumeClaimCondition_To_api_PersistentVolumeClaimCondition,
+		Convert_api_PersistentVolumeClaimCondition_To_v1_PersistentVolumeClaimCondition,
 		Convert_v1_PersistentVolumeClaimList_To_api_PersistentVolumeClaimList,
 		Convert_api_PersistentVolumeClaimList_To_v1_PersistentVolumeClaimList,
 		Convert_v1_PersistentVolumeClaimSpec_To_api_PersistentVolumeClaimSpec,
@@ -2942,6 +2944,36 @@ func Convert_api_PersistentVolumeClaim_To_v1_PersistentVolumeClaim(in *api.Persi
 	return autoConvert_api_PersistentVolumeClaim_To_v1_PersistentVolumeClaim(in, out, s)
 }
 
+func autoConvert_v1_PersistentVolumeClaimCondition_To_api_PersistentVolumeClaimCondition(in *v1.PersistentVolumeClaimCondition, out *api.PersistentVolumeClaimCondition, s conversion.Scope) error {
+	out.Type = api.PersistentVolumeClaimConditionType(in.Type)
+	out.Status = api.ConditionStatus(in.Status)
+	out.LastProbeTime = in.LastProbeTime
+	out.LastTransitionTime = in.LastTransitionTime
+	out.Reason = in.Reason
+	out.Message = in.Message
+	return nil
+}
+
+// Convert_v1_PersistentVolumeClaimCondition_To_api_PersistentVolumeClaimCondition is an autogenerated conversion function.
+func Convert_v1_PersistentVolumeClaimCondition_To_api_PersistentVolumeClaimCondition(in *v1.PersistentVolumeClaimCondition, out *api.PersistentVolumeClaimCondition, s conversion.Scope) error {
+	return autoConvert_v1_PersistentVolumeClaimCondition_To_api_PersistentVolumeClaimCondition(in, out, s)
+}
+
+func autoConvert_api_PersistentVolumeClaimCondition_To_v1_PersistentVolumeClaimCondition(in *api.PersistentVolumeClaimCondition, out *v1.PersistentVolumeClaimCondition, s conversion.Scope) error {
+	out.Type = v1.PersistentVolumeClaimConditionType(in.Type)
+	out.Status = v1.ConditionStatus(in.Status)
+	out.LastProbeTime = in.LastProbeTime
+	out.LastTransitionTime = in.LastTransitionTime
+	out.Reason = in.Reason
+	out.Message = in.Message
+	return nil
+}
+
+// Convert_api_PersistentVolumeClaimCondition_To_v1_PersistentVolumeClaimCondition is an autogenerated conversion function.
+func Convert_api_PersistentVolumeClaimCondition_To_v1_PersistentVolumeClaimCondition(in *api.PersistentVolumeClaimCondition, out *v1.PersistentVolumeClaimCondition, s conversion.Scope) error {
+	return autoConvert_api_PersistentVolumeClaimCondition_To_v1_PersistentVolumeClaimCondition(in, out, s)
+}
+
 func autoConvert_v1_PersistentVolumeClaimList_To_api_PersistentVolumeClaimList(in *v1.PersistentVolumeClaimList, out *api.PersistentVolumeClaimList, s conversion.Scope) error {
 	out.ListMeta = in.ListMeta
 	out.Items = *(*[]api.PersistentVolumeClaim)(unsafe.Pointer(&in.Items))
@@ -3000,6 +3032,7 @@ func autoConvert_v1_PersistentVolumeClaimStatus_To_api_PersistentVolumeClaimStat
 	out.Phase = api.PersistentVolumeClaimPhase(in.Phase)
 	out.AccessModes = *(*[]api.PersistentVolumeAccessMode)(unsafe.Pointer(&in.AccessModes))
 	out.Capacity = *(*api.ResourceList)(unsafe.Pointer(&in.Capacity))
+	out.Conditions = *(*[]api.PersistentVolumeClaimCondition)(unsafe.Pointer(&in.Conditions))
 	return nil
 }
 
@@ -3012,6 +3045,7 @@ func autoConvert_api_PersistentVolumeClaimStatus_To_v1_PersistentVolumeClaimStat
 	out.Phase = v1.PersistentVolumeClaimPhase(in.Phase)
 	out.AccessModes = *(*[]v1.PersistentVolumeAccessMode)(unsafe.Pointer(&in.AccessModes))
 	out.Capacity = *(*v1.ResourceList)(unsafe.Pointer(&in.Capacity))
+	out.Conditions = *(*[]v1.PersistentVolumeClaimCondition)(unsafe.Pointer(&in.Conditions))
 	return nil
 }
 

pkg/api/validation/validation.go

@@ -1588,10 +1588,31 @@ func ValidatePersistentVolumeClaimUpdate(newPvc, oldPvc *api.PersistentVolumeCla
 		oldPvc.Spec.VolumeName = newPvc.Spec.VolumeName
 		defer func() { oldPvc.Spec.VolumeName = "" }()
 	}
-	// changes to Spec are not allowed, but updates to label/and some annotations are OK.
-	// no-op updates pass validation.
-	if !apiequality.Semantic.DeepEqual(newPvc.Spec, oldPvc.Spec) {
-		allErrs = append(allErrs, field.Forbidden(field.NewPath("spec"), "field is immutable after creation"))
+
+	if utilfeature.DefaultFeatureGate.Enabled(features.ExpandPersistentVolumes) {
+		newPVCSpecCopy := newPvc.Spec.DeepCopy()
+
+		// lets make sure storage values are same.
+		if newPvc.Status.Phase == api.ClaimBound && newPVCSpecCopy.Resources.Requests != nil {
+			newPVCSpecCopy.Resources.Requests["storage"] = oldPvc.Spec.Resources.Requests["storage"]
+		}
+
+		oldSize := oldPvc.Spec.Resources.Requests["storage"]
+		newSize := newPvc.Spec.Resources.Requests["storage"]
+
+		if !apiequality.Semantic.DeepEqual(*newPVCSpecCopy, oldPvc.Spec) {
+			allErrs = append(allErrs, field.Forbidden(field.NewPath("spec"), "is immutable after creation except resources.requests for bound claims"))
+		}
+		if newSize.Cmp(oldSize) < 0 {
+			allErrs = append(allErrs, field.Forbidden(field.NewPath("spec", "resources", "requests", "storage"), "field can not be less than previous value"))
+		}
+
+	} else {
+		// changes to Spec are not allowed, but updates to label/and some annotations are OK.
+		// no-op updates pass validation.
+		if !apiequality.Semantic.DeepEqual(newPvc.Spec, oldPvc.Spec) {
+			allErrs = append(allErrs, field.Forbidden(field.NewPath("spec"), "field is immutable after creation"))
+		}
 	}
 
 	// storageclass annotation should be immutable after creation
@@ -1611,6 +1632,10 @@ func ValidatePersistentVolumeClaimStatusUpdate(newPvc, oldPvc *api.PersistentVol
 	if len(newPvc.Spec.AccessModes) == 0 {
 		allErrs = append(allErrs, field.Required(field.NewPath("Spec", "accessModes"), ""))
 	}
+	if !utilfeature.DefaultFeatureGate.Enabled(features.ExpandPersistentVolumes) && len(newPvc.Status.Conditions) > 0 {
+		conditionPath := field.NewPath("status", "conditions")
+		allErrs = append(allErrs, field.Forbidden(conditionPath, "invalid field"))
+	}
 	capPath := field.NewPath("status", "capacity")
 	for r, qty := range newPvc.Status.Capacity {
 		allErrs = append(allErrs, validateBasicResource(qty, capPath.Key(string(r)))...)

pkg/api/validation/validation_test.go

@@ -530,6 +530,17 @@ func testVolumeClaim(name string, namespace string, spec api.PersistentVolumeCla
 	}
 }
 
+func testVolumeClaimWithStatus(
+	name, namespace string,
+	spec api.PersistentVolumeClaimSpec,
+	status api.PersistentVolumeClaimStatus) *api.PersistentVolumeClaim {
+	return &api.PersistentVolumeClaim{
+		ObjectMeta: metav1.ObjectMeta{Name: name, Namespace: namespace},
+		Spec:       spec,
+		Status:     status,
+	}
+}
+
 func testVolumeClaimStorageClass(name string, namespace string, annval string, spec api.PersistentVolumeClaimSpec) *api.PersistentVolumeClaim {
 	annotations := map[string]string{
 		v1.BetaStorageClassAnnotation: annval,
@@ -728,7 +739,7 @@ func TestValidatePersistentVolumeClaim(t *testing.T) {
 }
 
 func TestValidatePersistentVolumeClaimUpdate(t *testing.T) {
-	validClaim := testVolumeClaim("foo", "ns", api.PersistentVolumeClaimSpec{
+	validClaim := testVolumeClaimWithStatus("foo", "ns", api.PersistentVolumeClaimSpec{
 		AccessModes: []api.PersistentVolumeAccessMode{
 			api.ReadWriteOnce,
 			api.ReadOnlyMany,
@@ -738,7 +749,10 @@ func TestValidatePersistentVolumeClaimUpdate(t *testing.T) {
 				api.ResourceName(api.ResourceStorage): resource.MustParse("10G"),
 			},
 		},
+	}, api.PersistentVolumeClaimStatus{
+		Phase: api.ClaimBound,
 	})
+
 	validClaimStorageClass := testVolumeClaimStorageClass("foo", "ns", "fast", api.PersistentVolumeClaimSpec{
 		AccessModes: []api.PersistentVolumeAccessMode{
 			api.ReadOnlyMany,
@@ -828,50 +842,125 @@ func TestValidatePersistentVolumeClaimUpdate(t *testing.T) {
 		},
 		VolumeName: "volume",
 	})
+	validSizeUpdate := testVolumeClaimWithStatus("foo", "ns", api.PersistentVolumeClaimSpec{
+		AccessModes: []api.PersistentVolumeAccessMode{
+			api.ReadWriteOnce,
+			api.ReadOnlyMany,
+		},
+		Resources: api.ResourceRequirements{
+			Requests: api.ResourceList{
+				api.ResourceName(api.ResourceStorage): resource.MustParse("15G"),
+			},
+		},
+	}, api.PersistentVolumeClaimStatus{
+		Phase: api.ClaimBound,
+	})
+
+	invalidSizeUpdate := testVolumeClaimWithStatus("foo", "ns", api.PersistentVolumeClaimSpec{
+		AccessModes: []api.PersistentVolumeAccessMode{
+			api.ReadWriteOnce,
+			api.ReadOnlyMany,
+		},
+		Resources: api.ResourceRequirements{
+			Requests: api.ResourceList{
+				api.ResourceName(api.ResourceStorage): resource.MustParse("5G"),
+			},
+		},
+	}, api.PersistentVolumeClaimStatus{
+		Phase: api.ClaimBound,
+	})
+
+	unboundSizeUpdate := testVolumeClaimWithStatus("foo", "ns", api.PersistentVolumeClaimSpec{
+		AccessModes: []api.PersistentVolumeAccessMode{
+			api.ReadWriteOnce,
+			api.ReadOnlyMany,
+		},
+		Resources: api.ResourceRequirements{
+			Requests: api.ResourceList{
+				api.ResourceName(api.ResourceStorage): resource.MustParse("12G"),
+			},
+		},
+	}, api.PersistentVolumeClaimStatus{
+		Phase: api.ClaimPending,
+	})
+
 	scenarios := map[string]struct {
 		isExpectedFailure bool
 		oldClaim          *api.PersistentVolumeClaim
 		newClaim          *api.PersistentVolumeClaim
+		enableResize      bool
 	}{
 		"valid-update-volumeName-only": {
 			isExpectedFailure: false,
 			oldClaim:          validClaim,
 			newClaim:          validUpdateClaim,
+			enableResize:      false,
 		},
 		"valid-no-op-update": {
 			isExpectedFailure: false,
 			oldClaim:          validUpdateClaim,
 			newClaim:          validUpdateClaim,
+			enableResize:      false,
 		},
 		"invalid-update-change-resources-on-bound-claim": {
 			isExpectedFailure: true,
 			oldClaim:          validUpdateClaim,
 			newClaim:          invalidUpdateClaimResources,
+			enableResize:      false,
 		},
 		"invalid-update-change-access-modes-on-bound-claim": {
 			isExpectedFailure: true,
 			oldClaim:          validUpdateClaim,
 			newClaim:          invalidUpdateClaimAccessModes,
+			enableResize:      false,
 		},
 		"invalid-update-change-storage-class-annotation-after-creation": {
 			isExpectedFailure: true,
 			oldClaim:          validClaimStorageClass,
 			newClaim:          invalidUpdateClaimStorageClass,
+			enableResize:      false,
 		},
 		"valid-update-mutable-annotation": {
 			isExpectedFailure: false,
 			oldClaim:          validClaimAnnotation,
 			newClaim:          validUpdateClaimMutableAnnotation,
+			enableResize:      false,
 		},
 		"valid-update-add-annotation": {
 			isExpectedFailure: false,
 			oldClaim:          validClaim,
 			newClaim:          validAddClaimAnnotation,
+			enableResize:      false,
+		},
+		"valid-size-update-resize-disabled": {
+			isExpectedFailure: true,
+			oldClaim:          validClaim,
+			newClaim:          validSizeUpdate,
+			enableResize:      false,
+		},
+		"valid-size-update-resize-enabled": {
+			isExpectedFailure: false,
+			oldClaim:          validClaim,
+			newClaim:          validSizeUpdate,
+			enableResize:      true,
+		},
+		"invalid-size-update-resize-enabled": {
+			isExpectedFailure: true,
+			oldClaim:          validClaim,
+			newClaim:          invalidSizeUpdate,
+			enableResize:      true,
+		},
+		"unbound-size-update-resize-enabled": {
+			isExpectedFailure: true,
+			oldClaim:          validClaim,
+			newClaim:          unboundSizeUpdate,
+			enableResize:      true,
 		},
 	}
 
 	for name, scenario := range scenarios {
 		// ensure we have a resource version specified for updates
+		togglePVExpandFeature(scenario.enableResize, t)
 		scenario.oldClaim.ResourceVersion = "1"
 		scenario.newClaim.ResourceVersion = "1"
 		errs := ValidatePersistentVolumeClaimUpdate(scenario.newClaim, scenario.oldClaim)
@@ -884,6 +973,23 @@ func TestValidatePersistentVolumeClaimUpdate(t *testing.T) {
 	}
 }
 
+func togglePVExpandFeature(toggleFlag bool, t *testing.T) {
+	if toggleFlag {
+		// Enable alpha feature LocalStorageCapacityIsolation
+		err := utilfeature.DefaultFeatureGate.Set("ExpandPersistentVolumes=true")
+		if err != nil {
+			t.Errorf("Failed to enable feature gate for ExpandPersistentVolumes: %v", err)
+			return
+		}
+	} else {
+		err := utilfeature.DefaultFeatureGate.Set("ExpandPersistentVolumes=false")
+		if err != nil {
+			t.Errorf("Failed to disable feature gate for ExpandPersistentVolumes: %v", err)
+			return
+		}
+	}
+}
+
 func TestValidateKeyToPath(t *testing.T) {
 	testCases := []struct {
 		kp      api.KeyToPath
@@ -9232,6 +9338,68 @@ func TestValidateLimitRange(t *testing.T) {
 
 }
 
+func TestValidatePersistentVolumeClaimStatusUpdate(t *testing.T) {
+	validClaim := testVolumeClaim("foo", "ns", api.PersistentVolumeClaimSpec{
+		AccessModes: []api.PersistentVolumeAccessMode{
+			api.ReadWriteOnce,
+			api.ReadOnlyMany,
+		},
+		Resources: api.ResourceRequirements{
+			Requests: api.ResourceList{
+				api.ResourceName(api.ResourceStorage): resource.MustParse("10G"),
+			},
+		},
+	})
+	validConditionUpdate := testVolumeClaimWithStatus("foo", "ns", api.PersistentVolumeClaimSpec{
+		AccessModes: []api.PersistentVolumeAccessMode{
+			api.ReadWriteOnce,
+			api.ReadOnlyMany,
+		},
+		Resources: api.ResourceRequirements{
+			Requests: api.ResourceList{
+				api.ResourceName(api.ResourceStorage): resource.MustParse("10G"),
+			},
+		},
+	}, api.PersistentVolumeClaimStatus{
+		Phase: api.ClaimPending,
+		Conditions: []api.PersistentVolumeClaimCondition{
+			{Type: api.PersistentVolumeClaimResizing, Status: api.ConditionTrue},
+		},
+	})
+	scenarios := map[string]struct {
+		isExpectedFailure bool
+		oldClaim          *api.PersistentVolumeClaim
+		newClaim          *api.PersistentVolumeClaim
+		enableResize      bool
+	}{
+		"condition-update-with-disabled-feature-gate": {
+			isExpectedFailure: true,
+			oldClaim:          validClaim,
+			newClaim:          validConditionUpdate,
+			enableResize:      false,
+		},
+		"condition-update-with-enabled-feature-gate": {
+			isExpectedFailure: false,
+			oldClaim:          validClaim,
+			newClaim:          validConditionUpdate,
+			enableResize:      true,
+		},
+	}
+	for name, scenario := range scenarios {
+		// ensure we have a resource version specified for updates
+		togglePVExpandFeature(scenario.enableResize, t)
+		scenario.oldClaim.ResourceVersion = "1"
+		scenario.newClaim.ResourceVersion = "1"
+		errs := ValidatePersistentVolumeClaimStatusUpdate(scenario.newClaim, scenario.oldClaim)
+		if len(errs) == 0 && scenario.isExpectedFailure {
+			t.Errorf("Unexpected success for scenario: %s", name)
+		}
+		if len(errs) > 0 && !scenario.isExpectedFailure {
+			t.Errorf("Unexpected failure for scenario: %s - %+v", name, errs)
+		}
+	}
+}
+
 func TestValidateResourceQuota(t *testing.T) {
 	spec := api.ResourceQuotaSpec{
 		Hard: api.ResourceList{

pkg/api/zz_generated.deepcopy.go

@@ -428,6 +428,10 @@ func RegisterDeepCopies(scheme *runtime.Scheme) error {
 			return nil
 		}, InType: reflect.TypeOf(&PersistentVolumeClaim{})},
 		conversion.GeneratedDeepCopyFunc{Fn: func(in interface{}, out interface{}, c *conversion.Cloner) error {
+			in.(*PersistentVolumeClaimCondition).DeepCopyInto(out.(*PersistentVolumeClaimCondition))
+			return nil
+		}, InType: reflect.TypeOf(&PersistentVolumeClaimCondition{})},
+		conversion.GeneratedDeepCopyFunc{Fn: func(in interface{}, out interface{}, c *conversion.Cloner) error {
 			in.(*PersistentVolumeClaimList).DeepCopyInto(out.(*PersistentVolumeClaimList))
 			return nil
 		}, InType: reflect.TypeOf(&PersistentVolumeClaimList{})},
@@ -3514,6 +3518,24 @@ func (in *PersistentVolumeClaim) DeepCopyObject() runtime.Object {
 }
 
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *PersistentVolumeClaimCondition) DeepCopyInto(out *PersistentVolumeClaimCondition) {
+	*out = *in
+	in.LastProbeTime.DeepCopyInto(&out.LastProbeTime)
+	in.LastTransitionTime.DeepCopyInto(&out.LastTransitionTime)
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new PersistentVolumeClaimCondition.
+func (in *PersistentVolumeClaimCondition) DeepCopy() *PersistentVolumeClaimCondition {
+	if in == nil {
+		return nil
+	}
+	out := new(PersistentVolumeClaimCondition)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *PersistentVolumeClaimList) DeepCopyInto(out *PersistentVolumeClaimList) {
 	*out = *in
 	out.TypeMeta = in.TypeMeta
@@ -3602,6 +3624,13 @@ func (in *PersistentVolumeClaimStatus) DeepCopyInto(out *PersistentVolumeClaimSt
 			(*out)[key] = val.DeepCopy()
 		}
 	}
+	if in.Conditions != nil {
+		in, out := &in.Conditions, &out.Conditions
+		*out = make([]PersistentVolumeClaimCondition, len(*in))
+		for i := range *in {
+			(*in)[i].DeepCopyInto(&(*out)[i])
+		}
+	}
 	return
 }
 

pkg/apis/storage/types.go

@@ -59,6 +59,12 @@ type StorageClass struct {
 	// PersistentVolumes of this storage class are created with
 	// +optional
 	MountOptions []string
+
+	// AllowVolumeExpansion shows whether the storage class allow volume expand
+	// If the field is nil or not set, it would amount to expansion disabled
+	// for all PVs created from this storageclass.
+	// +optional
+	AllowVolumeExpansion *bool
 }
 
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

pkg/apis/storage/v1/zz_generated.conversion.go

@@ -51,6 +51,7 @@ func autoConvert_v1_StorageClass_To_storage_StorageClass(in *v1.StorageClass, ou
 	out.Parameters = *(*map[string]string)(unsafe.Pointer(&in.Parameters))
 	out.ReclaimPolicy = (*api.PersistentVolumeReclaimPolicy)(unsafe.Pointer(in.ReclaimPolicy))
 	out.MountOptions = *(*[]string)(unsafe.Pointer(&in.MountOptions))
+	out.AllowVolumeExpansion = (*bool)(unsafe.Pointer(in.AllowVolumeExpansion))
 	return nil
 }
 
@@ -65,6 +66,7 @@ func autoConvert_storage_StorageClass_To_v1_StorageClass(in *storage.StorageClas
 	out.Parameters = *(*map[string]string)(unsafe.Pointer(&in.Parameters))
 	out.ReclaimPolicy = (*core_v1.PersistentVolumeReclaimPolicy)(unsafe.Pointer(in.ReclaimPolicy))
 	out.MountOptions = *(*[]string)(unsafe.Pointer(&in.MountOptions))
+	out.AllowVolumeExpansion = (*bool)(unsafe.Pointer(in.AllowVolumeExpansion))
 	return nil
 }
 

pkg/apis/storage/v1beta1/zz_generated.conversion.go

@@ -51,6 +51,7 @@ func autoConvert_v1beta1_StorageClass_To_storage_StorageClass(in *v1beta1.Storag
 	out.Parameters = *(*map[string]string)(unsafe.Pointer(&in.Parameters))
 	out.ReclaimPolicy = (*api.PersistentVolumeReclaimPolicy)(unsafe.Pointer(in.ReclaimPolicy))
 	out.MountOptions = *(*[]string)(unsafe.Pointer(&in.MountOptions))
+	out.AllowVolumeExpansion = (*bool)(unsafe.Pointer(in.AllowVolumeExpansion))
 	return nil
 }
 
@@ -65,6 +66,7 @@ func autoConvert_storage_StorageClass_To_v1beta1_StorageClass(in *storage.Storag
 	out.Parameters = *(*map[string]string)(unsafe.Pointer(&in.Parameters))
 	out.ReclaimPolicy = (*v1.PersistentVolumeReclaimPolicy)(unsafe.Pointer(in.ReclaimPolicy))
 	out.MountOptions = *(*[]string)(unsafe.Pointer(&in.MountOptions))
+	out.AllowVolumeExpansion = (*bool)(unsafe.Pointer(in.AllowVolumeExpansion))
 	return nil
 }
 

pkg/apis/storage/validation/BUILD

@@ -13,9 +13,11 @@ go_library(
         "//pkg/api:go_default_library",
         "//pkg/api/validation:go_default_library",
         "//pkg/apis/storage:go_default_library",
+        "//pkg/features:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/sets:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/validation:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/validation/field:go_default_library",
+        "//vendor/k8s.io/apiserver/pkg/util/feature:go_default_library",
     ],
 )
 
@@ -27,6 +29,7 @@ go_test(
         "//pkg/api:go_default_library",
         "//pkg/apis/storage:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/apiserver/pkg/util/feature:go_default_library",
     ],
 )
 

pkg/apis/storage/validation/validation.go

@@ -23,9 +23,11 @@ import (
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/validation"
 	"k8s.io/apimachinery/pkg/util/validation/field"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/kubernetes/pkg/api"
 	apivalidation "k8s.io/kubernetes/pkg/api/validation"
 	"k8s.io/kubernetes/pkg/apis/storage"
+	"k8s.io/kubernetes/pkg/features"
 )
 
 // ValidateStorageClass validates a StorageClass.
@@ -34,6 +36,7 @@ func ValidateStorageClass(storageClass *storage.StorageClass) field.ErrorList {
 	allErrs = append(allErrs, validateProvisioner(storageClass.Provisioner, field.NewPath("provisioner"))...)
 	allErrs = append(allErrs, validateParameters(storageClass.Parameters, field.NewPath("parameters"))...)
 	allErrs = append(allErrs, validateReclaimPolicy(storageClass.ReclaimPolicy, field.NewPath("reclaimPolicy"))...)
+	allErrs = append(allErrs, validateAllowVolumeExpansion(storageClass.AllowVolumeExpansion, field.NewPath("allowVolumeExpansion"))...)
 
 	return allErrs
 }
@@ -108,3 +111,13 @@ func validateReclaimPolicy(reclaimPolicy *api.PersistentVolumeReclaimPolicy, fld
 	}
 	return allErrs
 }
+
+// validateAllowVolumeExpansion tests that if ExpandPersistentVolumes feature gate is disabled, whether the AllowVolumeExpansion filed
+// of storage class is set
+func validateAllowVolumeExpansion(allowExpand *bool, fldPath *field.Path) field.ErrorList {
+	allErrs := field.ErrorList{}
+	if allowExpand != nil && !utilfeature.DefaultFeatureGate.Enabled(features.ExpandPersistentVolumes) {
+		allErrs = append(allErrs, field.Forbidden(fldPath, "field is disabled by feature-gate ExpandPersistentVolumes"))
+	}
+	return allErrs
+}

pkg/apis/storage/validation/validation_test.go

@@ -21,6 +21,7 @@ import (
 	"testing"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/apis/storage"
 )
@@ -123,3 +124,36 @@ func TestValidateStorageClass(t *testing.T) {
 		}
 	}
 }
+
+func TestAlphaExpandPersistentVolumesFeatureValidation(t *testing.T) {
+	deleteReclaimPolicy := api.PersistentVolumeReclaimPolicy("Delete")
+	falseVar := false
+	testSC := &storage.StorageClass{
+		// empty parameters
+		ObjectMeta:           metav1.ObjectMeta{Name: "foo"},
+		Provisioner:          "kubernetes.io/foo-provisioner",
+		Parameters:           map[string]string{},
+		ReclaimPolicy:        &deleteReclaimPolicy,
+		AllowVolumeExpansion: &falseVar,
+	}
+
+	// Enable alpha feature ExpandPersistentVolumes
+	err := utilfeature.DefaultFeatureGate.Set("ExpandPersistentVolumes=true")
+	if err != nil {
+		t.Errorf("Failed to enable feature gate for ExpandPersistentVolumes: %v", err)
+		return
+	}
+	if errs := ValidateStorageClass(testSC); len(errs) != 0 {
+		t.Errorf("expected success: %v", errs)
+	}
+	// Disable alpha feature ExpandPersistentVolumes
+	err = utilfeature.DefaultFeatureGate.Set("ExpandPersistentVolumes=false")
+	if err != nil {
+		t.Errorf("Failed to disable feature gate for ExpandPersistentVolumes: %v", err)
+		return
+	}
+	if errs := ValidateStorageClass(testSC); len(errs) == 0 {
+		t.Errorf("expected failure, but got no error")
+	}
+
+}

pkg/apis/storage/zz_generated.deepcopy.go

@@ -74,6 +74,15 @@ func (in *StorageClass) DeepCopyInto(out *StorageClass) {
 		*out = make([]string, len(*in))
 		copy(*out, *in)
 	}
+	if in.AllowVolumeExpansion != nil {
+		in, out := &in.AllowVolumeExpansion, &out.AllowVolumeExpansion
+		if *in == nil {
+			*out = nil
+		} else {
+			*out = new(bool)
+			**out = **in
+		}
+	}
 	return
 }
 

pkg/controller/BUILD

@@ -128,6 +128,7 @@ filegroup(
         "//pkg/controller/ttl:all-srcs",
         "//pkg/controller/volume/attachdetach:all-srcs",
         "//pkg/controller/volume/events:all-srcs",
+        "//pkg/controller/volume/expand:all-srcs",
         "//pkg/controller/volume/persistentvolume:all-srcs",
     ],
     tags = ["automanaged"],

pkg/controller/volume/expand/BUILD

+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "expand_controller.go",
+        "pvc_populator.go",
+        "sync_volume_resize.go",
+    ],
+    tags = ["automanaged"],
+    deps = [
+        "//pkg/cloudprovider:go_default_library",
+        "//pkg/controller:go_default_library",
+        "//pkg/controller/volume/expand/cache:go_default_library",
+        "//pkg/controller/volume/expand/util:go_default_library",
+        "//pkg/util/goroutinemap/exponentialbackoff:go_default_library",
+        "//pkg/util/io:go_default_library",
+        "//pkg/util/mount:go_default_library",
+        "//pkg/volume:go_default_library",
+        "//pkg/volume/util/operationexecutor:go_default_library",
+        "//vendor/github.com/golang/glog:go_default_library",
+        "//vendor/k8s.io/api/core/v1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/labels:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/types:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/util/runtime:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/util/wait:go_default_library",
+        "//vendor/k8s.io/client-go/informers/core/v1:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes/scheme:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes/typed/core/v1:go_default_library",
+        "//vendor/k8s.io/client-go/listers/core/v1:go_default_library",
+        "//vendor/k8s.io/client-go/tools/cache:go_default_library",
+        "//vendor/k8s.io/client-go/tools/record:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [
+        ":package-srcs",
+        "//pkg/controller/volume/expand/cache:all-srcs",
+        "//pkg/controller/volume/expand/util:all-srcs",
+    ],
+    tags = ["automanaged"],
+)

pkg/controller/volume/expand/OWNERS

+approvers:
+- saad-ali
+- jsafrane
+- gnufied

pkg/controller/volume/expand/cache/BUILD

+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+    "go_test",
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = ["volume_resize_map.go"],
+    tags = ["automanaged"],
+    deps = [
+        "//pkg/controller/volume/expand/util:go_default_library",
+        "//pkg/util/strings:go_default_library",
+        "//pkg/volume/util/types:go_default_library",
+        "//vendor/github.com/golang/glog:go_default_library",
+        "//vendor/k8s.io/api/core/v1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/api/resource:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/types:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/util/strategicpatch:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["volume_resize_map_test.go"],
+    library = ":go_default_library",
+    deps = [
+        "//pkg/volume/util/types:go_default_library",
+        "//vendor/github.com/stretchr/testify/assert:go_default_library",
+        "//vendor/k8s.io/api/core/v1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/api/resource:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes/fake:go_default_library",
+    ],
+)

pkg/controller/volume/expand/cache/volume_resize_map.go

+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cache
+
+import (
+	"encoding/json"
+	"fmt"
+	"sync"
+
+	"github.com/golang/glog"
+	"k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
+	commontypes "k8s.io/apimachinery/pkg/types"
+	"k8s.io/apimachinery/pkg/util/strategicpatch"
+	clientset "k8s.io/client-go/kubernetes"
+	"k8s.io/kubernetes/pkg/controller/volume/expand/util"
+	"k8s.io/kubernetes/pkg/util/strings"
+	"k8s.io/kubernetes/pkg/volume/util/types"
+)
+
+// VolumeResizeMap defines an interface that serves as a cache for holding pending resizing requests
+type VolumeResizeMap interface {
+	// AddPVCUpdate adds pvc for resizing
+	AddPVCUpdate(pvc *v1.PersistentVolumeClaim, pv *v1.PersistentVolume)
+	// DeletePVC deletes pvc that is scheduled for resizing
+	DeletePVC(pvc *v1.PersistentVolumeClaim)
+	// GetPVCsWithResizeRequest returns all pending pvc resize requests
+	GetPVCsWithResizeRequest() []*PVCWithResizeRequest
+	// MarkAsResized marks a pvc as fully resized
+	MarkAsResized(*PVCWithResizeRequest, resource.Quantity) error
+	// UpdatePVSize updates just pv size after cloudprovider resizing is successful
+	UpdatePVSize(*PVCWithResizeRequest, resource.Quantity) error
+}
+
+type volumeResizeMap struct {
+	// map of unique pvc name and resize requests that are pending or inflight
+	pvcrs map[types.UniquePVCName]*PVCWithResizeRequest
+	// kube client for making API calls
+	kubeClient clientset.Interface
+	// for guarding access to pvcrs map
+	sync.RWMutex
+}
+
+// PVCWithResizeRequest struct defines data structure that stores state needed for
+// performing file system resize
+type PVCWithResizeRequest struct {
+	// PVC that needs to be resized
+	PVC *v1.PersistentVolumeClaim
+	// persistentvolume
+	PersistentVolume *v1.PersistentVolume
+	// Current volume size
+	CurrentSize resource.Quantity
+	// Expended volume size
+	ExpectedSize resource.Quantity
+}
+
+// UniquePVCKey returns unique key of the PVC based on its UID
+func (pvcr *PVCWithResizeRequest) UniquePVCKey() types.UniquePVCName {
+	return types.UniquePVCName(pvcr.PVC.UID)
+}
+
+// QualifiedName returns namespace and name combination of the PVC
+func (pvcr *PVCWithResizeRequest) QualifiedName() string {
+	return strings.JoinQualifiedName(pvcr.PVC.Namespace, pvcr.PVC.Name)
+}
+
+// NewVolumeResizeMap returns new VolumeResizeMap which acts as a cache
+// for holding pending resize requests.
+func NewVolumeResizeMap(kubeClient clientset.Interface) VolumeResizeMap {
+	resizeMap := &volumeResizeMap{}
+	resizeMap.pvcrs = make(map[types.UniquePVCName]*PVCWithResizeRequest)
+	resizeMap.kubeClient = kubeClient
+	return resizeMap
+}
+
+// AddPVCUpdate adds pvc for resizing
+func (resizeMap *volumeResizeMap) AddPVCUpdate(pvc *v1.PersistentVolumeClaim, pv *v1.PersistentVolume) {
+	if pvc.Namespace != pv.Spec.ClaimRef.Namespace || pvc.Name != pv.Spec.ClaimRef.Name {
+		glog.V(4).Infof("Persistent Volume is not mapped to PVC being updated : %s", util.ClaimToClaimKey(pvc))
+		return
+	}
+
+	if pvc.Status.Phase != v1.ClaimBound {
+		return
+	}
+
+	resizeMap.Lock()
+	defer resizeMap.Unlock()
+
+	pvcSize := pvc.Spec.Resources.Requests[v1.ResourceStorage]
+	pvcStatusSize := pvc.Status.Capacity[v1.ResourceStorage]
+
+	if pvcStatusSize.Cmp(pvcSize) >= 0 {
+		return
+	}
+
+	glog.V(4).Infof("Adding pvc %s with Size %s/%s for resizing", util.ClaimToClaimKey(pvc), pvcSize.String(), pvcStatusSize.String())
+
+	pvcRequest := &PVCWithResizeRequest{
+		PVC:              pvc,
+		CurrentSize:      pvcStatusSize,
+		ExpectedSize:     pvcSize,
+		PersistentVolume: pv,
+	}
+	resizeMap.pvcrs[types.UniquePVCName(pvc.UID)] = pvcRequest
+}
+
+// GetPVCsWithResizeRequest returns all pending pvc resize requests
+func (resizeMap *volumeResizeMap) GetPVCsWithResizeRequest() []*PVCWithResizeRequest {
+	resizeMap.Lock()
+	defer resizeMap.Unlock()
+
+	pvcrs := []*PVCWithResizeRequest{}
+	for _, pvcr := range resizeMap.pvcrs {
+		pvcrs = append(pvcrs, pvcr)
+	}
+	// Empty out pvcrs map, we will add back failed resize requests later
+	resizeMap.pvcrs = map[types.UniquePVCName]*PVCWithResizeRequest{}
+	return pvcrs
+}
+
+// DeletePVC removes given pvc object from list of pvcs that needs resizing.
+// deleting a pvc in this map doesn't affect operations that are already inflight.
+func (resizeMap *volumeResizeMap) DeletePVC(pvc *v1.PersistentVolumeClaim) {
+	resizeMap.Lock()
+	defer resizeMap.Unlock()
+	pvcUniqueName := types.UniquePVCName(pvc.UID)
+	glog.V(5).Infof("Removing PVC %v from resize map", pvcUniqueName)
+	delete(resizeMap.pvcrs, pvcUniqueName)
+}
+
+// MarkAsResized marks a pvc as fully resized
+func (resizeMap *volumeResizeMap) MarkAsResized(pvcr *PVCWithResizeRequest, newSize resource.Quantity) error {
+	resizeMap.Lock()
+	defer resizeMap.Unlock()
+
+	emptyCondition := []v1.PersistentVolumeClaimCondition{}
+
+	err := resizeMap.updatePVCCapacityAndConditions(pvcr, newSize, emptyCondition)
+	if err != nil {
+		glog.V(4).Infof("Error updating PV spec capacity for volume %q with : %v", pvcr.QualifiedName(), err)
+		return err
+	}
+	return nil
+}
+
+// UpdatePVSize updates just pv size after cloudprovider resizing is successful
+func (resizeMap *volumeResizeMap) UpdatePVSize(pvcr *PVCWithResizeRequest, newSize resource.Quantity) error {
+	resizeMap.Lock()
+	defer resizeMap.Unlock()
+
+	oldPv := pvcr.PersistentVolume
+	pvClone := oldPv.DeepCopy()
+
+	oldData, err := json.Marshal(pvClone)
+
+	if err != nil {
+		return fmt.Errorf("Unexpected error marshaling PV : %q with error %v", pvClone.Name, err)
+	}
+
+	pvClone.Spec.Capacity[v1.ResourceStorage] = newSize
+
+	newData, err := json.Marshal(pvClone)
+
+	if err != nil {
+		return fmt.Errorf("Unexpected error marshaling PV : %q with error %v", pvClone.Name, err)
+	}
+
+	patchBytes, err := strategicpatch.CreateTwoWayMergePatch(oldData, newData, pvClone)
+
+	if err != nil {
+		return fmt.Errorf("Error Creating two way merge patch for  PV : %q with error %v", pvClone.Name, err)
+	}
+
+	_, updateErr := resizeMap.kubeClient.CoreV1().PersistentVolumes().Patch(pvClone.Name, commontypes.StrategicMergePatchType, patchBytes)
+
+	if updateErr != nil {
+		glog.V(4).Infof("Error updating pv %q with error : %v", pvClone.Name, updateErr)
+		return updateErr
+	}
+	return nil
+}
+
+func (resizeMap *volumeResizeMap) updatePVCCapacityAndConditions(pvcr *PVCWithResizeRequest, newSize resource.Quantity, pvcConditions []v1.PersistentVolumeClaimCondition) error {
+
+	claimClone := pvcr.PVC.DeepCopy()
+
+	claimClone.Status.Capacity[v1.ResourceStorage] = newSize
+	claimClone.Status.Conditions = pvcConditions
+
+	_, updateErr := resizeMap.kubeClient.CoreV1().PersistentVolumeClaims(claimClone.Namespace).UpdateStatus(claimClone)
+	if updateErr != nil {
+		glog.V(4).Infof("updating PersistentVolumeClaim[%s] status: failed: %v", pvcr.QualifiedName(), updateErr)
+		return updateErr
+	}
+	return nil
+}

pkg/controller/volume/expand/cache/volume_resize_map_test.go

+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cache
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes/fake"
+	"k8s.io/kubernetes/pkg/volume/util/types"
+)
+
+func Test_AddValidPvcUpdate(t *testing.T) {
+	resizeMap := createTestVolumeResizeMap()
+	claim1 := testVolumeClaim("foo", "ns", v1.PersistentVolumeClaimSpec{
+		AccessModes: []v1.PersistentVolumeAccessMode{
+			v1.ReadWriteOnce,
+			v1.ReadOnlyMany,
+		},
+		Resources: v1.ResourceRequirements{
+			Requests: v1.ResourceList{
+				v1.ResourceName(v1.ResourceStorage): resource.MustParse("10G"),
+			},
+		},
+		VolumeName: "foo",
+	})
+
+	claimClone := claim1.DeepCopy()
+	claimClone.Spec.Resources.Requests[v1.ResourceStorage] = resource.MustParse("12G")
+	pv := getPersistentVolume("foo", resource.MustParse("10G"), claim1)
+	resizeMap.AddPVCUpdate(claimClone, pv)
+	pvcr := resizeMap.GetPVCsWithResizeRequest()
+	if len(pvcr) != 1 {
+		t.Fatalf("Expected 1 pvc resize request got 0")
+	}
+	assert.Equal(t, resource.MustParse("12G"), pvcr[0].ExpectedSize)
+	assert.Equal(t, 0, len(resizeMap.pvcrs))
+}
+
+func createTestVolumeResizeMap() *volumeResizeMap {
+	fakeClient := &fake.Clientset{}
+	resizeMap := &volumeResizeMap{}
+	resizeMap.pvcrs = make(map[types.UniquePVCName]*PVCWithResizeRequest)
+	resizeMap.kubeClient = fakeClient
+	return resizeMap
+}
+
+func testVolumeClaim(name string, namespace string, spec v1.PersistentVolumeClaimSpec) *v1.PersistentVolumeClaim {
+	return &v1.PersistentVolumeClaim{
+		ObjectMeta: metav1.ObjectMeta{Name: name, Namespace: namespace},
+		Spec:       spec,
+		Status: v1.PersistentVolumeClaimStatus{
+			Phase: v1.ClaimBound,
+		},
+	}
+}
+
+func getPersistentVolume(volumeName string, capacity resource.Quantity, pvc *v1.PersistentVolumeClaim) *v1.PersistentVolume {
+	return &v1.PersistentVolume{
+		ObjectMeta: metav1.ObjectMeta{Name: volumeName},
+		Spec: v1.PersistentVolumeSpec{
+			Capacity: v1.ResourceList{
+				v1.ResourceName(v1.ResourceStorage): capacity,
+			},
+			ClaimRef: &v1.ObjectReference{
+				Namespace: pvc.Namespace,
+				Name:      pvc.Name,
+			},
+		},
+	}
+}

pkg/controller/volume/expand/expand_controller.go

+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package expand implements interfaces that attempt to resize a pvc
+// by adding pvc to a volume resize map from which PVCs are picked and
+// resized
+package expand
+
+import (
+	"fmt"
+	"net"
+	"time"
+
+	"github.com/golang/glog"
+
+	"k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/apimachinery/pkg/util/runtime"
+	coreinformers "k8s.io/client-go/informers/core/v1"
+	clientset "k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/kubernetes/scheme"
+	v1core "k8s.io/client-go/kubernetes/typed/core/v1"
+	corelisters "k8s.io/client-go/listers/core/v1"
+	kcache "k8s.io/client-go/tools/cache"
+	"k8s.io/client-go/tools/record"
+	"k8s.io/kubernetes/pkg/cloudprovider"
+	"k8s.io/kubernetes/pkg/controller"
+	"k8s.io/kubernetes/pkg/controller/volume/expand/cache"
+	"k8s.io/kubernetes/pkg/util/io"
+	"k8s.io/kubernetes/pkg/util/mount"
+	"k8s.io/kubernetes/pkg/volume"
+	"k8s.io/kubernetes/pkg/volume/util/operationexecutor"
+)
+
+const (
+	// How often resizing loop runs
+	syncLoopPeriod time.Duration = 30 * time.Second
+	// How often pvc populator runs
+	populatorLoopPeriod time.Duration = 2 * time.Minute
+)
+
+// ExpandController expands the pvs
+type ExpandController interface {
+	Run(stopCh <-chan struct{})
+}
+
+type expandController struct {
+	// kubeClient is the kube API client used by volumehost to communicate with
+	// the API server.
+	kubeClient clientset.Interface
+
+	// pvcLister is the shared PVC lister used to fetch and store PVC
+	// objects from the API server. It is shared with other controllers and
+	// therefore the PVC objects in its store should be treated as immutable.
+	pvcLister  corelisters.PersistentVolumeClaimLister
+	pvcsSynced kcache.InformerSynced
+
+	pvLister corelisters.PersistentVolumeLister
+	pvSynced kcache.InformerSynced
+
+	// cloud provider used by volume host
+	cloud cloudprovider.Interface
+
+	// volumePluginMgr used to initialize and fetch volume plugins
+	volumePluginMgr volume.VolumePluginMgr
+
+	// recorder is used to record events in the API server
+	recorder record.EventRecorder
+
+	// Volume resize map of volumes that needs resizing
+	resizeMap cache.VolumeResizeMap
+
+	// Worker goroutine to process resize requests from resizeMap
+	syncResize SyncVolumeResize
+
+	// Operation executor
+	opExecutor operationexecutor.OperationExecutor
+
+	// populator for periodically polling all PVCs
+	pvcPopulator PVCPopulator
+}
+
+func NewExpandController(
+	kubeClient clientset.Interface,
+	pvcInformer coreinformers.PersistentVolumeClaimInformer,
+	pvInformer coreinformers.PersistentVolumeInformer,
+	cloud cloudprovider.Interface,
+	plugins []volume.VolumePlugin) (ExpandController, error) {
+
+	expc := &expandController{
+		kubeClient: kubeClient,
+		cloud:      cloud,
+		pvcLister:  pvcInformer.Lister(),
+		pvcsSynced: pvcInformer.Informer().HasSynced,
+		pvLister:   pvInformer.Lister(),
+		pvSynced:   pvInformer.Informer().HasSynced,
+	}
+
+	if err := expc.volumePluginMgr.InitPlugins(plugins, nil, expc); err != nil {
+		return nil, fmt.Errorf("Could not initialize volume plugins for Expand Controller : %+v", err)
+	}
+
+	eventBroadcaster := record.NewBroadcaster()
+	eventBroadcaster.StartLogging(glog.Infof)
+	eventBroadcaster.StartRecordingToSink(&v1core.EventSinkImpl{Interface: v1core.New(kubeClient.CoreV1().RESTClient()).Events("")})
+	recorder := eventBroadcaster.NewRecorder(scheme.Scheme, v1.EventSource{Component: "volume_expand"})
+
+	expc.opExecutor = operationexecutor.NewOperationExecutor(operationexecutor.NewOperationGenerator(
+		kubeClient,
+		&expc.volumePluginMgr,
+		recorder,
+		false))
+
+	expc.resizeMap = cache.NewVolumeResizeMap(expc.kubeClient)
+
+	pvcInformer.Informer().AddEventHandler(kcache.ResourceEventHandlerFuncs{
+		UpdateFunc: expc.pvcUpdate,
+		DeleteFunc: expc.deletePVC,
+	})
+
+	expc.syncResize = NewSyncVolumeResize(syncLoopPeriod, expc.opExecutor, expc.resizeMap, kubeClient)
+	expc.pvcPopulator = NewPVCPopulator(
+		populatorLoopPeriod,
+		expc.resizeMap,
+		expc.pvcLister,
+		expc.pvLister,
+		kubeClient)
+	return expc, nil
+}
+
+func (expc *expandController) Run(stopCh <-chan struct{}) {
+	defer runtime.HandleCrash()
+	glog.Infof("Starting expand controller")
+	defer glog.Infof("Shutting down expand controller")
+
+	if !controller.WaitForCacheSync("expand", stopCh, expc.pvcsSynced, expc.pvSynced) {
+		return
+	}
+
+	// Run volume sync work goroutine
+	go expc.syncResize.Run(stopCh)
+	// Start the pvc populator loop
+	go expc.pvcPopulator.Run(stopCh)
+	<-stopCh
+}
+
+func (expc *expandController) deletePVC(obj interface{}) {
+	pvc, ok := obj.(*v1.PersistentVolumeClaim)
+
+	if pvc == nil || !ok {
+		return
+	}
+
+	expc.resizeMap.DeletePVC(pvc)
+}
+
+func (expc *expandController) pvcUpdate(oldObj, newObj interface{}) {
+	oldPvc, ok := oldObj.(*v1.PersistentVolumeClaim)
+
+	if oldPvc == nil || !ok {
+		return
+	}
+
+	newPVC, ok := newObj.(*v1.PersistentVolumeClaim)
+
+	if newPVC == nil || !ok {
+		return
+	}
+	pv, err := getPersistentVolume(newPVC, expc.pvLister)
+	if err != nil {
+		glog.V(5).Infof("Error getting Persistent Volume for pvc %q : %v", newPVC.UID, err)
+		return
+	}
+	expc.resizeMap.AddPVCUpdate(newPVC, pv)
+}
+
+func getPersistentVolume(pvc *v1.PersistentVolumeClaim, pvLister corelisters.PersistentVolumeLister) (*v1.PersistentVolume, error) {
+	volumeName := pvc.Spec.VolumeName
+	pv, err := pvLister.Get(volumeName)
+
+	if err != nil {
+		return nil, fmt.Errorf("failed to find PV %q in PV informer cache with error : %v", volumeName, err)
+	}
+
+	return pv.DeepCopy(), nil
+}
+
+// Implementing VolumeHost interface
+func (expc *expandController) GetPluginDir(pluginName string) string {
+	return ""
+}
+
+func (expc *expandController) GetPodVolumeDir(podUID types.UID, pluginName string, volumeName string) string {
+	return ""
+}
+
+func (expc *expandController) GetPodPluginDir(podUID types.UID, pluginName string) string {
+	return ""
+}
+
+func (expc *expandController) GetKubeClient() clientset.Interface {
+	return expc.kubeClient
+}
+
+func (expc *expandController) NewWrapperMounter(volName string, spec volume.Spec, pod *v1.Pod, opts volume.VolumeOptions) (volume.Mounter, error) {
+	return nil, fmt.Errorf("NewWrapperMounter not supported by expand controller's VolumeHost implementation")
+}
+
+func (expc *expandController) NewWrapperUnmounter(volName string, spec volume.Spec, podUID types.UID) (volume.Unmounter, error) {
+	return nil, fmt.Errorf("NewWrapperUnmounter not supported by expand controller's VolumeHost implementation")
+}
+
+func (expc *expandController) GetCloudProvider() cloudprovider.Interface {
+	return expc.cloud
+}
+
+func (expc *expandController) GetMounter(pluginName string) mount.Interface {
+	return nil
+}
+
+func (expc *expandController) GetExec(pluginName string) mount.Exec {
+	return mount.NewOsExec()
+}
+
+func (expc *expandController) GetWriter() io.Writer {
+	return nil
+}
+
+func (expc *expandController) GetHostName() string {
+	return ""
+}
+
+func (expc *expandController) GetHostIP() (net.IP, error) {
+	return nil, fmt.Errorf("GetHostIP not supported by expand controller's VolumeHost implementation")
+}
+
+func (expc *expandController) GetNodeAllocatable() (v1.ResourceList, error) {
+	return v1.ResourceList{}, nil
+}
+
+func (expc *expandController) GetSecretFunc() func(namespace, name string) (*v1.Secret, error) {
+	return func(_, _ string) (*v1.Secret, error) {
+		return nil, fmt.Errorf("GetSecret unsupported in expandController")
+	}
+}
+
+func (expc *expandController) GetConfigMapFunc() func(namespace, name string) (*v1.ConfigMap, error) {
+	return func(_, _ string) (*v1.ConfigMap, error) {
+		return nil, fmt.Errorf("GetConfigMap unsupported in expandController")
+	}
+}
+
+func (expc *expandController) GetNodeLabels() (map[string]string, error) {
+	return nil, fmt.Errorf("GetNodeLabels unsupported in expandController")
+}

pkg/controller/volume/expand/pvc_populator.go

+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package reconciler implements interfaces that attempt to reconcile the
+// desired state of the with the actual state of the world by triggering
+// actions.
+
+package expand
+
+import (
+	"time"
+
+	"github.com/golang/glog"
+
+	"k8s.io/apimachinery/pkg/labels"
+	"k8s.io/apimachinery/pkg/util/wait"
+	clientset "k8s.io/client-go/kubernetes"
+	corelisters "k8s.io/client-go/listers/core/v1"
+	"k8s.io/kubernetes/pkg/controller/volume/expand/cache"
+)
+
+// PVCPopulator iterates through PVCs and checks if for bound PVCs
+// their size doesn't match with Persistent Volume size
+type PVCPopulator interface {
+	Run(stopCh <-chan struct{})
+}
+
+type pvcPopulator struct {
+	loopPeriod time.Duration
+	resizeMap  cache.VolumeResizeMap
+	pvcLister  corelisters.PersistentVolumeClaimLister
+	pvLister   corelisters.PersistentVolumeLister
+	kubeClient clientset.Interface
+}
+
+func NewPVCPopulator(
+	loopPeriod time.Duration,
+	resizeMap cache.VolumeResizeMap,
+	pvcLister corelisters.PersistentVolumeClaimLister,
+	pvLister corelisters.PersistentVolumeLister,
+	kubeClient clientset.Interface) PVCPopulator {
+	populator := &pvcPopulator{
+		loopPeriod: loopPeriod,
+		pvcLister:  pvcLister,
+		pvLister:   pvLister,
+		resizeMap:  resizeMap,
+		kubeClient: kubeClient,
+	}
+	return populator
+}
+
+func (populator *pvcPopulator) Run(stopCh <-chan struct{}) {
+	wait.Until(populator.Sync, populator.loopPeriod, stopCh)
+}
+
+func (populator *pvcPopulator) Sync() {
+	pvcs, err := populator.pvcLister.List(labels.Everything())
+	if err != nil {
+		glog.Errorf("Listing PVCs failed in populator : %v", err)
+		return
+	}
+
+	for _, pvc := range pvcs {
+		pv, err := getPersistentVolume(pvc, populator.pvLister)
+
+		if err != nil {
+			glog.V(5).Infof("Error getting persistent volume for pvc %q : %v", pvc.UID, err)
+			continue
+		}
+		populator.resizeMap.AddPVCUpdate(pvc, pv)
+	}
+}

pkg/controller/volume/expand/sync_volume_resize.go

+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package expand
+
+import (
+	"time"
+
+	"github.com/golang/glog"
+	"k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/util/wait"
+	clientset "k8s.io/client-go/kubernetes"
+	"k8s.io/kubernetes/pkg/controller/volume/expand/cache"
+	"k8s.io/kubernetes/pkg/controller/volume/expand/util"
+	"k8s.io/kubernetes/pkg/util/goroutinemap/exponentialbackoff"
+	"k8s.io/kubernetes/pkg/volume/util/operationexecutor"
+)
+
+type SyncVolumeResize interface {
+	Run(stopCh <-chan struct{})
+}
+
+type syncResize struct {
+	loopPeriod  time.Duration
+	resizeMap   cache.VolumeResizeMap
+	opsExecutor operationexecutor.OperationExecutor
+	kubeClient  clientset.Interface
+}
+
+// NewSyncVolumeResize returns actual volume resize handler
+func NewSyncVolumeResize(
+	loopPeriod time.Duration,
+	opsExecutor operationexecutor.OperationExecutor,
+	resizeMap cache.VolumeResizeMap,
+	kubeClient clientset.Interface) SyncVolumeResize {
+	rc := &syncResize{
+		loopPeriod:  loopPeriod,
+		opsExecutor: opsExecutor,
+		resizeMap:   resizeMap,
+		kubeClient:  kubeClient,
+	}
+	return rc
+}
+
+func (rc *syncResize) Run(stopCh <-chan struct{}) {
+	wait.Until(rc.Sync, rc.loopPeriod, stopCh)
+}
+
+func (rc *syncResize) Sync() {
+	// Resize PVCs that require resize
+	for _, pvcWithResizeRequest := range rc.resizeMap.GetPVCsWithResizeRequest() {
+		uniqueVolumeKey := v1.UniqueVolumeName(pvcWithResizeRequest.UniquePVCKey())
+		updatedClaim, err := markPVCResizeInProgress(pvcWithResizeRequest, rc.kubeClient)
+		if err != nil {
+			glog.V(5).Infof("Error setting PVC %s in progress with error : %v", pvcWithResizeRequest.QualifiedName(), err)
+			continue
+		}
+		if updatedClaim != nil {
+			pvcWithResizeRequest.PVC = updatedClaim
+		}
+
+		if rc.opsExecutor.IsOperationPending(uniqueVolumeKey, "") {
+			glog.V(10).Infof("Operation for PVC %v is already pending", pvcWithResizeRequest.QualifiedName())
+			continue
+		}
+		glog.V(5).Infof("Starting opsExecutor.ExpandVolume for volume %s", pvcWithResizeRequest.QualifiedName())
+		growFuncError := rc.opsExecutor.ExpandVolume(pvcWithResizeRequest, rc.resizeMap)
+		if growFuncError != nil && !exponentialbackoff.IsExponentialBackoff(growFuncError) {
+			glog.Errorf("Error growing pvc %s with %v", pvcWithResizeRequest.QualifiedName(), growFuncError)
+		}
+		if growFuncError == nil {
+			glog.V(5).Infof("Started opsExecutor.ExpandVolume for volume %s", pvcWithResizeRequest.QualifiedName())
+		}
+	}
+}
+
+func markPVCResizeInProgress(pvcWithResizeRequest *cache.PVCWithResizeRequest, kubeClient clientset.Interface) (*v1.PersistentVolumeClaim, error) {
+	// Mark PVC as Resize Started
+	progressCondition := v1.PersistentVolumeClaimCondition{
+		Type:               v1.PersistentVolumeClaimResizing,
+		Status:             v1.ConditionTrue,
+		LastTransitionTime: metav1.Now(),
+	}
+	conditions := []v1.PersistentVolumeClaimCondition{progressCondition}
+
+	return util.UpdatePVCCondition(pvcWithResizeRequest.PVC, conditions, kubeClient)
+}

pkg/controller/volume/expand/util/BUILD

+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["util.go"],
+    visibility = ["//visibility:public"],
+    deps = [
+        "//vendor/github.com/golang/glog:go_default_library",
+        "//vendor/k8s.io/api/core/v1:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

pkg/controller/volume/expand/util/util.go

+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package util
+
+import (
+	"fmt"
+
+	"github.com/golang/glog"
+
+	"k8s.io/api/core/v1"
+	clientset "k8s.io/client-go/kubernetes"
+)
+
+// ClaimToClaimKey return namespace/name string for pvc
+func ClaimToClaimKey(claim *v1.PersistentVolumeClaim) string {
+	return fmt.Sprintf("%s/%s", claim.Namespace, claim.Name)
+}
+
+// UpdatePVCCondition updates pvc with given condition status
+func UpdatePVCCondition(pvc *v1.PersistentVolumeClaim,
+	pvcConditions []v1.PersistentVolumeClaimCondition,
+	kubeClient clientset.Interface) (*v1.PersistentVolumeClaim, error) {
+
+	claimClone := pvc.DeepCopy()
+	claimClone.Status.Conditions = pvcConditions
+	updatedClaim, updateErr := kubeClient.CoreV1().PersistentVolumeClaims(claimClone.Namespace).UpdateStatus(claimClone)
+	if updateErr != nil {
+		glog.V(4).Infof("updating PersistentVolumeClaim[%s] status: failed: %v", ClaimToClaimKey(pvc), updateErr)
+		return nil, updateErr
+	}
+	return updatedClaim, nil
+}

pkg/features/kube_features.go

@@ -114,6 +114,11 @@ const (
 	// New local storage types to support local storage capacity isolation
 	LocalStorageCapacityIsolation utilfeature.Feature = "LocalStorageCapacityIsolation"
 
+	// owner: @gnufied
+	// alpha: v1.8
+	// Ability to Expand persistent volumes
+	ExpandPersistentVolumes utilfeature.Feature = "ExpandPersistentVolumes"
+
 	// owner: @verb
 	// alpha: v1.8
 	//
@@ -179,6 +184,7 @@ var defaultKubernetesFeatureGates = map[utilfeature.Feature]utilfeature.FeatureS
 	EnableEquivalenceClassCache:                 {Default: false, PreRelease: utilfeature.Alpha},
 	TaintNodesByCondition:                       {Default: false, PreRelease: utilfeature.Alpha},
 	MountPropagation:                            {Default: false, PreRelease: utilfeature.Alpha},
+	ExpandPersistentVolumes:                     {Default: false, PreRelease: utilfeature.Alpha},
 
 	// inherited features from generic apiserver, relisted here to get a conflict if it is changed
 	// unintentionally on either side:

pkg/kubelet/events/event.go

@@ -45,6 +45,7 @@ const (
 	FailedAttachVolume                   = "FailedAttachVolume"
 	FailedDetachVolume                   = "FailedDetachVolume"
 	FailedMountVolume                    = "FailedMount"
+	VolumeResizeFailed                   = "VolumeResizeFailed"
 	FailedUnMountVolume                  = "FailedUnMount"
 	WarnAlreadyMountedVolume             = "AlreadyMountedVolume"
 	SuccessfulDetachVolume               = "SuccessfulDetachVolume"

pkg/quota/evaluator/core/BUILD

@@ -25,6 +25,7 @@ go_library(
         "//pkg/api/helper/qos:go_default_library",
         "//pkg/api/v1:go_default_library",
         "//pkg/api/validation:go_default_library",
+        "//pkg/features:go_default_library",
         "//pkg/kubeapiserver/admission/util:go_default_library",
         "//pkg/quota:go_default_library",
         "//pkg/quota/generic:go_default_library",
@@ -36,6 +37,7 @@ go_library(
         "//vendor/k8s.io/apimachinery/pkg/util/sets:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/validation/field:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/admission:go_default_library",
+        "//vendor/k8s.io/apiserver/pkg/util/feature:go_default_library",
         "//vendor/k8s.io/client-go/informers:go_default_library",
         "//vendor/k8s.io/client-go/kubernetes:go_default_library",
     ],

pkg/quota/evaluator/core/persistent_volume_claims.go

@@ -27,11 +27,13 @@ import (
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apiserver/pkg/admission"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/client-go/informers"
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/api/helper"
 	k8s_api_v1 "k8s.io/kubernetes/pkg/api/v1"
+	"k8s.io/kubernetes/pkg/features"
 	"k8s.io/kubernetes/pkg/kubeapiserver/admission/util"
 	"k8s.io/kubernetes/pkg/quota"
 	"k8s.io/kubernetes/pkg/quota/generic"
@@ -147,6 +149,10 @@ func (p *pvcEvaluator) Handles(a admission.Attributes) bool {
 	if op == admission.Create {
 		return true
 	}
+	if op == admission.Update && utilfeature.DefaultFeatureGate.Enabled(features.ExpandPersistentVolumes) {
+		return true
+	}
+
 	updateUninitialized, err := util.IsUpdatingUninitializedObject(a)
 	if err != nil {
 		// fail closed, will try to give an evaluation.

pkg/registry/storage/storageclass/BUILD

@@ -16,10 +16,12 @@ go_library(
         "//pkg/api:go_default_library",
         "//pkg/apis/storage:go_default_library",
         "//pkg/apis/storage/validation:go_default_library",
+        "//pkg/features:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/util/validation/field:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/endpoints/request:go_default_library",
         "//vendor/k8s.io/apiserver/pkg/storage/names:go_default_library",
+        "//vendor/k8s.io/apiserver/pkg/util/feature:go_default_library",
     ],
 )
 

pkg/registry/storage/storageclass/strategy.go

@@ -21,9 +21,11 @@ import (
 	"k8s.io/apimachinery/pkg/util/validation/field"
 	genericapirequest "k8s.io/apiserver/pkg/endpoints/request"
 	"k8s.io/apiserver/pkg/storage/names"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/apis/storage"
 	"k8s.io/kubernetes/pkg/apis/storage/validation"
+	"k8s.io/kubernetes/pkg/features"
 )
 
 // storageClassStrategy implements behavior for StorageClass objects
@@ -42,7 +44,11 @@ func (storageClassStrategy) NamespaceScoped() bool {
 
 // ResetBeforeCreate clears the Status field which is not allowed to be set by end users on creation.
 func (storageClassStrategy) PrepareForCreate(ctx genericapirequest.Context, obj runtime.Object) {
-	_ = obj.(*storage.StorageClass)
+	class := obj.(*storage.StorageClass)
+
+	if !utilfeature.DefaultFeatureGate.Enabled(features.ExpandPersistentVolumes) {
+		class.AllowVolumeExpansion = nil
+	}
 }
 
 func (storageClassStrategy) Validate(ctx genericapirequest.Context, obj runtime.Object) field.ErrorList {
@@ -60,8 +66,13 @@ func (storageClassStrategy) AllowCreateOnUpdate() bool {
 
 // PrepareForUpdate sets the Status fields which is not allowed to be set by an end user updating a PV
 func (storageClassStrategy) PrepareForUpdate(ctx genericapirequest.Context, obj, old runtime.Object) {
-	_ = obj.(*storage.StorageClass)
-	_ = old.(*storage.StorageClass)
+	newClass := obj.(*storage.StorageClass)
+	oldClass := old.(*storage.StorageClass)
+
+	if !utilfeature.DefaultFeatureGate.Enabled(features.ExpandPersistentVolumes) {
+		newClass.AllowVolumeExpansion = nil
+		oldClass.AllowVolumeExpansion = nil
+	}
 }
 
 func (storageClassStrategy) ValidateUpdate(ctx genericapirequest.Context, obj, old runtime.Object) field.ErrorList {

pkg/volume/glusterfs/glusterfs.go

@@ -127,6 +127,10 @@ func (plugin *glusterfsPlugin) SupportsBulkVolumeVerification() bool {
 	return false
 }
 
+func (plugin *glusterfsPlugin) RequiresFSResize() bool {
+	return false
+}
+
 func (plugin *glusterfsPlugin) GetAccessModes() []v1.PersistentVolumeAccessMode {
 	return []v1.PersistentVolumeAccessMode{
 		v1.ReadWriteOnce,
@@ -1046,3 +1050,49 @@ func parseClassParameters(params map[string]string, kubeClient clientset.Interfa
 	}
 	return &cfg, nil
 }
+
+func (plugin *glusterfsPlugin) ExpandVolumeDevice(spec *volume.Spec, newSize resource.Quantity, oldSize resource.Quantity) (resource.Quantity, error) {
+	pvSpec := spec.PersistentVolume.Spec
+	glog.V(2).Infof("Request to expand volume: %s ", pvSpec.Glusterfs.Path)
+	volumeName := pvSpec.Glusterfs.Path
+
+	// Fetch the volume for expansion.
+	volumeID := dstrings.TrimPrefix(volumeName, volPrefix)
+
+	//Get details of SC.
+	class, err := volutil.GetClassForVolume(plugin.host.GetKubeClient(), spec.PersistentVolume)
+	if err != nil {
+		return oldSize, err
+	}
+	cfg, err := parseClassParameters(class.Parameters, plugin.host.GetKubeClient())
+	if err != nil {
+		return oldSize, err
+	}
+
+	glog.V(4).Infof("Expanding volume %q with configuration %+v", volumeID, cfg)
+
+	//Create REST server connection
+	cli := gcli.NewClient(cfg.url, cfg.user, cfg.secretValue)
+	if cli == nil {
+		glog.Errorf("failed to create glusterfs rest client")
+		return oldSize, fmt.Errorf("failed to create glusterfs rest client, REST server authentication failed")
+	}
+
+	// Find out delta size
+	expansionSize := (newSize.Value() - oldSize.Value())
+	expansionSizeGB := int(volume.RoundUpSize(expansionSize, 1024*1024*1024))
+
+	// Make volume expansion request
+	volumeExpandReq := &gapi.VolumeExpandRequest{Size: expansionSizeGB}
+
+	// Expand the volume
+	volumeInfoRes, err := cli.VolumeExpand(volumeID, volumeExpandReq)
+	if err != nil {
+		glog.Errorf("error when expanding the volume :%v", err)
+		return oldSize, err
+	}
+
+	glog.V(2).Infof("volume %s expanded to new size %d successfully", volumeName, volumeInfoRes.Size)
+	newVolumeSize := resource.MustParse(fmt.Sprintf("%dG", volumeInfoRes.Size))
+	return newVolumeSize, nil
+}

pkg/volume/plugins.go

@@ -24,6 +24,7 @@ import (
 
 	"github.com/golang/glog"
 	"k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	utilerrors "k8s.io/apimachinery/pkg/util/errors"
@@ -201,6 +202,14 @@ type AttachableVolumePlugin interface {
 	GetDeviceMountRefs(deviceMountPath string) ([]string, error)
 }
 
+// ExpandableVolumePlugin is an extended interface of VolumePlugin and is used for volumes that can be
+// expanded
+type ExpandableVolumePlugin interface {
+	VolumePlugin
+	ExpandVolumeDevice(spec *Spec, newSize resource.Quantity, oldSize resource.Quantity) (resource.Quantity, error)
+	RequiresFSResize() bool
+}
+
 // VolumeHost is an interface that plugins can use to access the kubelet.
 type VolumeHost interface {
 	// GetPluginDir returns the absolute path to a directory under which
@@ -642,6 +651,32 @@ func (pm *VolumePluginMgr) FindAttachablePluginByName(name string) (AttachableVo
 	return nil, nil
 }
 
+// FindExpandablePluginBySpec fetches a persistent volume plugin by spec.
+func (pm *VolumePluginMgr) FindExpandablePluginBySpec(spec *Spec) (ExpandableVolumePlugin, error) {
+	volumePlugin, err := pm.FindPluginBySpec(spec)
+	if err != nil {
+		return nil, err
+	}
+
+	if expandableVolumePlugin, ok := volumePlugin.(ExpandableVolumePlugin); ok {
+		return expandableVolumePlugin, nil
+	}
+	return nil, nil
+}
+
+// FindExpandablePluginBySpec fetches a persistent volume plugin by name.
+func (pm *VolumePluginMgr) FindExpandablePluginByName(name string) (ExpandableVolumePlugin, error) {
+	volumePlugin, err := pm.FindPluginByName(name)
+	if err != nil {
+		return nil, err
+	}
+
+	if expandableVolumePlugin, ok := volumePlugin.(ExpandableVolumePlugin); ok {
+		return expandableVolumePlugin, nil
+	}
+	return nil, nil
+}
+
 // NewPersistentVolumeRecyclerPodTemplate creates a template for a recycler
 // pod.  By default, a recycler pod simply runs "rm -rf" on a volume and tests
 // for emptiness.  Most attributes of the template will be correct for most

pkg/volume/util/operationexecutor/BUILD

@@ -13,6 +13,7 @@ go_library(
         "operation_generator.go",
     ],
     deps = [
+        "//pkg/controller/volume/expand/cache:go_default_library",
         "//pkg/features:go_default_library",
         "//pkg/kubelet/events:go_default_library",
         "//pkg/util/mount:go_default_library",
@@ -37,6 +38,7 @@ go_test(
     srcs = ["operation_executor_test.go"],
     library = ":go_default_library",
     deps = [
+        "//pkg/controller/volume/expand/cache:go_default_library",
         "//pkg/util/mount:go_default_library",
         "//pkg/volume:go_default_library",
         "//pkg/volume/util/types:go_default_library",

pkg/volume/util/operationexecutor/operation_executor.go

@@ -29,6 +29,7 @@ import (
 
 	"k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/types"
+	expandcache "k8s.io/kubernetes/pkg/controller/volume/expand/cache"
 	"k8s.io/kubernetes/pkg/util/mount"
 	"k8s.io/kubernetes/pkg/volume"
 	"k8s.io/kubernetes/pkg/volume/util"
@@ -119,6 +120,8 @@ type OperationExecutor interface {
 	// IsOperationPending returns true if an operation for the given volumeName and podName is pending,
 	// otherwise it returns false
 	IsOperationPending(volumeName v1.UniqueVolumeName, podName volumetypes.UniquePodName) bool
+	// Expand Volume will grow size available to PVC
+	ExpandVolume(*expandcache.PVCWithResizeRequest, expandcache.VolumeResizeMap) error
 }
 
 // NewOperationExecutor returns a new instance of OperationExecutor.
@@ -719,6 +722,17 @@ func (oe *operationExecutor) UnmountDevice(
 		deviceToDetach.VolumeName, "" /* podName */, unmountDeviceFunc, opCompleteFunc)
 }
 
+func (oe *operationExecutor) ExpandVolume(pvcWithResizeRequest *expandcache.PVCWithResizeRequest, resizeMap expandcache.VolumeResizeMap) error {
+	expandFunc, pluginName, err := oe.operationGenerator.GenerateExpandVolumeFunc(pvcWithResizeRequest, resizeMap)
+
+	if err != nil {
+		return err
+	}
+	uniqueVolumeKey := v1.UniqueVolumeName(pvcWithResizeRequest.UniquePVCKey())
+	opCompleteFunc := util.OperationCompleteHook(pluginName, "expand_volume")
+	return oe.pendingOperations.Run(uniqueVolumeKey, "", expandFunc, opCompleteFunc)
+}
+
 func (oe *operationExecutor) VerifyControllerAttachedVolume(
 	volumeToMount VolumeToMount,
 	nodeName types.NodeName,

pkg/volume/util/operationexecutor/operation_executor_test.go

@@ -25,6 +25,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/apimachinery/pkg/util/uuid"
+	expandcache "k8s.io/kubernetes/pkg/controller/volume/expand/cache"
 	"k8s.io/kubernetes/pkg/util/mount"
 	"k8s.io/kubernetes/pkg/volume"
 	volumetypes "k8s.io/kubernetes/pkg/volume/util/types"
@@ -282,6 +283,14 @@ func (fopg *fakeOperationGenerator) GenerateVerifyControllerAttachedVolumeFunc(v
 	}, "", nil
 }
 
+func (fopg *fakeOperationGenerator) GenerateExpandVolumeFunc(pvcWithResizeRequest *expandcache.PVCWithResizeRequest,
+	resizeMap expandcache.VolumeResizeMap) (func() error, string, error) {
+	return func() error {
+		startOperationAndBlock(fopg.ch, fopg.quit)
+		return nil
+	}, "", nil
+}
+
 func (fopg *fakeOperationGenerator) GenerateBulkVolumeVerifyFunc(
 	pluginNodeVolumes map[types.NodeName][]*volume.Spec,
 	pluginNane string,

pkg/volume/util/operationexecutor/operation_generator.go

@@ -28,6 +28,7 @@ import (
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/tools/record"
+	expandcache "k8s.io/kubernetes/pkg/controller/volume/expand/cache"
 	"k8s.io/kubernetes/pkg/features"
 	kevents "k8s.io/kubernetes/pkg/kubelet/events"
 	"k8s.io/kubernetes/pkg/util/mount"
@@ -100,6 +101,8 @@ type OperationGenerator interface {
 		map[types.NodeName][]*volume.Spec,
 		string,
 		map[*volume.Spec]v1.UniqueVolumeName, ActualStateOfWorldAttacherUpdater) (func() error, error)
+
+	GenerateExpandVolumeFunc(*expandcache.PVCWithResizeRequest, expandcache.VolumeResizeMap) (func() error, string, error)
 }
 
 func (og *operationGenerator) GenerateVolumesAreAttachedFunc(
@@ -726,6 +729,59 @@ func (og *operationGenerator) verifyVolumeIsSafeToDetach(
 	return nil
 }
 
+func (og *operationGenerator) GenerateExpandVolumeFunc(
+	pvcWithResizeRequest *expandcache.PVCWithResizeRequest,
+	resizeMap expandcache.VolumeResizeMap) (func() error, string, error) {
+
+	volumeSpec := volume.NewSpecFromPersistentVolume(pvcWithResizeRequest.PersistentVolume, false)
+
+	volumePlugin, err := og.volumePluginMgr.FindExpandablePluginBySpec(volumeSpec)
+
+	if err != nil {
+		return nil, "", fmt.Errorf("Error finding plugin for expanding volume: %q with error %v", pvcWithResizeRequest.QualifiedName(), err)
+	}
+
+	expandFunc := func() error {
+		newSize := pvcWithResizeRequest.ExpectedSize
+		pvSize := pvcWithResizeRequest.PersistentVolume.Spec.Capacity[v1.ResourceStorage]
+		if pvSize.Cmp(newSize) < 0 {
+			updatedSize, expandErr := volumePlugin.ExpandVolumeDevice(
+				volumeSpec,
+				pvcWithResizeRequest.ExpectedSize,
+				pvcWithResizeRequest.CurrentSize)
+
+			if expandErr != nil {
+				glog.Errorf("Error expanding volume %q of plugin %s : %v", pvcWithResizeRequest.QualifiedName(), volumePlugin.GetPluginName(), expandErr)
+				og.recorder.Eventf(pvcWithResizeRequest.PVC, v1.EventTypeWarning, kevents.VolumeResizeFailed, expandErr.Error())
+				return expandErr
+			}
+			newSize = updatedSize
+			updateErr := resizeMap.UpdatePVSize(pvcWithResizeRequest, newSize)
+
+			if updateErr != nil {
+				glog.V(4).Infof("Error updating PV spec capacity for volume %q with : %v", pvcWithResizeRequest.QualifiedName(), updateErr)
+				og.recorder.Eventf(pvcWithResizeRequest.PVC, v1.EventTypeWarning, kevents.VolumeResizeFailed, updateErr.Error())
+				return updateErr
+			}
+		}
+
+		// No Cloudprovider resize needed, lets mark resizing as done
+		if !volumePlugin.RequiresFSResize() {
+			glog.V(4).Infof("Controller resizing done for PVC %s", pvcWithResizeRequest.QualifiedName())
+			err := resizeMap.MarkAsResized(pvcWithResizeRequest, newSize)
+
+			if err != nil {
+				glog.Errorf("Error marking pvc %s as resized : %v", pvcWithResizeRequest.QualifiedName(), err)
+				og.recorder.Eventf(pvcWithResizeRequest.PVC, v1.EventTypeWarning, kevents.VolumeResizeFailed, err.Error())
+				return err
+			}
+		}
+		return nil
+
+	}
+	return expandFunc, volumePlugin.GetPluginName(), nil
+}
+
 func checkMountOptionSupport(og *operationGenerator, volumeToMount VolumeToMount, plugin volume.VolumePlugin) error {
 	mountOptions := volume.MountOptionFromSpec(volumeToMount.VolumeSpec)
 

pkg/volume/util/types/types.go

@@ -21,3 +21,6 @@ import "k8s.io/apimachinery/pkg/types"
 
 // UniquePodName defines the type to key pods off of
 type UniquePodName types.UID
+
+// UniquePVCName defines the type to key pvc off
+type UniquePVCName types.UID

plugin/BUILD

@@ -28,6 +28,7 @@ filegroup(
         "//plugin/pkg/admission/namespace/exists:all-srcs",
         "//plugin/pkg/admission/noderestriction:all-srcs",
         "//plugin/pkg/admission/persistentvolume/label:all-srcs",
+        "//plugin/pkg/admission/persistentvolume/resize:all-srcs",
         "//plugin/pkg/admission/podnodeselector:all-srcs",
         "//plugin/pkg/admission/podpreset:all-srcs",
         "//plugin/pkg/admission/podtolerationrestriction:all-srcs",

plugin/pkg/admission/persistentvolume/resize/BUILD

+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+    "go_test",
+)
+
+go_test(
+    name = "go_default_test",
+    srcs = ["admission_test.go"],
+    library = ":go_default_library",
+    tags = ["automanaged"],
+    deps = [
+        "//pkg/api:go_default_library",
+        "//pkg/apis/storage:go_default_library",
+        "//pkg/client/informers/informers_generated/internalversion:go_default_library",
+        "//pkg/controller:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/api/resource:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/runtime/schema:go_default_library",
+        "//vendor/k8s.io/apiserver/pkg/admission:go_default_library",
+    ],
+)
+
+go_library(
+    name = "go_default_library",
+    srcs = ["admission.go"],
+    tags = ["automanaged"],
+    deps = [
+        "//pkg/api:go_default_library",
+        "//pkg/api/helper:go_default_library",
+        "//pkg/client/informers/informers_generated/internalversion:go_default_library",
+        "//pkg/client/listers/core/internalversion:go_default_library",
+        "//pkg/client/listers/storage/internalversion:go_default_library",
+        "//pkg/kubeapiserver/admission:go_default_library",
+        "//vendor/k8s.io/apiserver/pkg/admission:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+)

plugin/pkg/admission/persistentvolume/resize/admission.go

+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package resize
+
+import (
+	"fmt"
+	"io"
+
+	"k8s.io/apiserver/pkg/admission"
+	"k8s.io/kubernetes/pkg/api"
+	apihelper "k8s.io/kubernetes/pkg/api/helper"
+	informers "k8s.io/kubernetes/pkg/client/informers/informers_generated/internalversion"
+	pvlister "k8s.io/kubernetes/pkg/client/listers/core/internalversion"
+	storagelisters "k8s.io/kubernetes/pkg/client/listers/storage/internalversion"
+	kubeapiserveradmission "k8s.io/kubernetes/pkg/kubeapiserver/admission"
+)
+
+const (
+	// PluginName is the name of pvc resize admission plugin
+	PluginName = "PersistentVolumeClaimResize"
+)
+
+// Register registers a plugin
+func Register(plugins *admission.Plugins) {
+	plugins.Register(PluginName, func(config io.Reader) (admission.Interface, error) {
+		plugin := newPlugin()
+		return plugin, nil
+	})
+}
+
+var _ admission.Interface = &persistentVolumeClaimResize{}
+var _ = kubeapiserveradmission.WantsInternalKubeInformerFactory(&persistentVolumeClaimResize{})
+
+type persistentVolumeClaimResize struct {
+	*admission.Handler
+
+	pvLister pvlister.PersistentVolumeLister
+	scLister storagelisters.StorageClassLister
+}
+
+func newPlugin() *persistentVolumeClaimResize {
+	return &persistentVolumeClaimResize{
+		Handler: admission.NewHandler(admission.Update),
+	}
+}
+
+func (pvcr *persistentVolumeClaimResize) SetInternalKubeInformerFactory(f informers.SharedInformerFactory) {
+	pvcInformer := f.Core().InternalVersion().PersistentVolumes()
+	pvcr.pvLister = pvcInformer.Lister()
+	scInformer := f.Storage().InternalVersion().StorageClasses()
+	pvcr.scLister = scInformer.Lister()
+	pvcr.SetReadyFunc(func() bool {
+		return pvcInformer.Informer().HasSynced() && scInformer.Informer().HasSynced()
+	})
+}
+
+// Validate ensures lister is set.
+func (pvcr *persistentVolumeClaimResize) Validate() error {
+	if pvcr.pvLister == nil {
+		return fmt.Errorf("missing persistent volume lister")
+	}
+	if pvcr.scLister == nil {
+		return fmt.Errorf("missing storageclass lister")
+	}
+	return nil
+}
+
+func (pvcr *persistentVolumeClaimResize) Admit(a admission.Attributes) error {
+	if a.GetResource().GroupResource() != api.Resource("persistentvolumeclaims") {
+		return nil
+	}
+
+	if len(a.GetSubresource()) != 0 {
+		return nil
+	}
+
+	pvc, ok := a.GetObject().(*api.PersistentVolumeClaim)
+	// if we can't convert then we don't handle this object so just return
+	if !ok {
+		return nil
+	}
+	oldPvc, ok := a.GetOldObject().(*api.PersistentVolumeClaim)
+	if !ok {
+		return nil
+	}
+
+	// Growing Persistent volumes is only allowed for PVCs for which their StorageClass
+	// explicitly allows it
+	if !pvcr.allowResize(pvc, oldPvc) {
+		return admission.NewForbidden(a, fmt.Errorf("only dynamically provisioned pvc can be resized and "+
+			"the storageclass that provisions the pvc must support resize"))
+	}
+
+	// volume plugin must support resize
+	pv, err := pvcr.pvLister.Get(pvc.Spec.VolumeName)
+	if err != nil {
+		return nil
+	}
+
+	if !pvcr.checkVolumePlugin(pv) {
+		return admission.NewForbidden(a, fmt.Errorf("volume plugin does not support resize"))
+	}
+
+	return nil
+}
+
+// Growing Persistent volumes is only allowed for PVCs for which their StorageClass
+// explicitly allows it.
+func (pvcr *persistentVolumeClaimResize) allowResize(pvc, oldPvc *api.PersistentVolumeClaim) bool {
+	pvcStorageClass := apihelper.GetPersistentVolumeClaimClass(pvc)
+	oldPvcStorageClass := apihelper.GetPersistentVolumeClaimClass(oldPvc)
+	if pvcStorageClass == "" || oldPvcStorageClass == "" || pvcStorageClass != oldPvcStorageClass {
+		return false
+	}
+	sc, err := pvcr.scLister.Get(pvcStorageClass)
+	if err != nil {
+		return false
+	}
+	if sc.AllowVolumeExpansion != nil {
+		return *sc.AllowVolumeExpansion
+	}
+	return false
+}
+
+// checkVolumePlugin checks whether the volume plugin supports resize
+func (pvcr *persistentVolumeClaimResize) checkVolumePlugin(pv *api.PersistentVolume) bool {
+	if pv.Spec.Glusterfs != nil {
+		return true
+	}
+	return false
+
+}

plugin/pkg/admission/persistentvolume/resize/admission_test.go

+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package resize
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"k8s.io/apimachinery/pkg/api/resource"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apiserver/pkg/admission"
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/apis/storage"
+	informers "k8s.io/kubernetes/pkg/client/informers/informers_generated/internalversion"
+	"k8s.io/kubernetes/pkg/controller"
+)
+
+func getResourceList(storage string) api.ResourceList {
+	res := api.ResourceList{}
+	if storage != "" {
+		res[api.ResourceStorage] = resource.MustParse(storage)
+	}
+	return res
+}
+
+func TestPVCResizeAdmission(t *testing.T) {
+	goldClassName := "gold"
+	trueVal := true
+	falseVar := false
+	goldClass := &storage.StorageClass{
+		TypeMeta: metav1.TypeMeta{
+			Kind: "StorageClass",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name: goldClassName,
+		},
+		Provisioner:          "kubernetes.io/glusterfs",
+		AllowVolumeExpansion: &trueVal,
+	}
+	silverClassName := "silver"
+	silverClass := &storage.StorageClass{
+		TypeMeta: metav1.TypeMeta{
+			Kind: "StorageClass",
+		},
+		ObjectMeta: metav1.ObjectMeta{
+			Name: silverClassName,
+		},
+		Provisioner:          "kubernetes.io/glusterfs",
+		AllowVolumeExpansion: &falseVar,
+	}
+	expectNoError := func(err error) bool {
+		return err == nil
+	}
+	expectDynamicallyProvisionedError := func(err error) bool {
+		return strings.Contains(err.Error(), "only dynamically provisioned pvc can be resized and "+
+			"the storageclass that provisions the pvc must support resize")
+	}
+	expectVolumePluginError := func(err error) bool {
+		return strings.Contains(err.Error(), "volume plugin does not support resize")
+	}
+	tests := []struct {
+		name        string
+		resource    schema.GroupVersionResource
+		subresource string
+		oldObj      runtime.Object
+		newObj      runtime.Object
+
+		checkError func(error) bool
+	}{
+		{
+			name:     "pvc-resize, update, no error",
+			resource: api.SchemeGroupVersion.WithResource("persistentvolumeclaims"),
+			oldObj: &api.PersistentVolumeClaim{
+				Spec: api.PersistentVolumeClaimSpec{
+					VolumeName: "volume1",
+					Resources: api.ResourceRequirements{
+						Requests: getResourceList("1Gi"),
+					},
+					StorageClassName: &goldClassName,
+				},
+				Status: api.PersistentVolumeClaimStatus{
+					Capacity: getResourceList("1Gi"),
+				},
+			},
+			newObj: &api.PersistentVolumeClaim{
+				Spec: api.PersistentVolumeClaimSpec{
+					VolumeName: "volume1",
+					Resources: api.ResourceRequirements{
+						Requests: getResourceList("2Gi"),
+					},
+					StorageClassName: &goldClassName,
+				},
+				Status: api.PersistentVolumeClaimStatus{
+					Capacity: getResourceList("2Gi"),
+				},
+			},
+			checkError: expectNoError,
+		},
+		{
+			name:     "pvc-resize, update, volume plugin error",
+			resource: api.SchemeGroupVersion.WithResource("persistentvolumeclaims"),
+			oldObj: &api.PersistentVolumeClaim{
+				Spec: api.PersistentVolumeClaimSpec{
+					VolumeName: "volume2",
+					Resources: api.ResourceRequirements{
+						Requests: getResourceList("1Gi"),
+					},
+					StorageClassName: &goldClassName,
+				},
+				Status: api.PersistentVolumeClaimStatus{
+					Capacity: getResourceList("1Gi"),
+				},
+			},
+			newObj: &api.PersistentVolumeClaim{
+				Spec: api.PersistentVolumeClaimSpec{
+					VolumeName: "volume2",
+					Resources: api.ResourceRequirements{
+						Requests: getResourceList("2Gi"),
+					},
+					StorageClassName: &goldClassName,
+				},
+				Status: api.PersistentVolumeClaimStatus{
+					Capacity: getResourceList("2Gi"),
+				},
+			},
+			checkError: expectVolumePluginError,
+		},
+		{
+			name:     "pvc-resize, update, dynamically provisioned error",
+			resource: api.SchemeGroupVersion.WithResource("persistentvolumeclaims"),
+			oldObj: &api.PersistentVolumeClaim{
+				Spec: api.PersistentVolumeClaimSpec{
+					VolumeName: "volume3",
+					Resources: api.ResourceRequirements{
+						Requests: getResourceList("1Gi"),
+					},
+				},
+				Status: api.PersistentVolumeClaimStatus{
+					Capacity: getResourceList("1Gi"),
+				},
+			},
+			newObj: &api.PersistentVolumeClaim{
+				Spec: api.PersistentVolumeClaimSpec{
+					VolumeName: "volume3",
+					Resources: api.ResourceRequirements{
+						Requests: getResourceList("2Gi"),
+					},
+				},
+				Status: api.PersistentVolumeClaimStatus{
+					Capacity: getResourceList("2Gi"),
+				},
+			},
+			checkError: expectDynamicallyProvisionedError,
+		},
+		{
+			name:     "pvc-resize, update, dynamically provisioned error",
+			resource: api.SchemeGroupVersion.WithResource("persistentvolumeclaims"),
+			oldObj: &api.PersistentVolumeClaim{
+				Spec: api.PersistentVolumeClaimSpec{
+					VolumeName: "volume4",
+					Resources: api.ResourceRequirements{
+						Requests: getResourceList("1Gi"),
+					},
+					StorageClassName: &silverClassName,
+				},
+				Status: api.PersistentVolumeClaimStatus{
+					Capacity: getResourceList("1Gi"),
+				},
+			},
+			newObj: &api.PersistentVolumeClaim{
+				Spec: api.PersistentVolumeClaimSpec{
+					VolumeName: "volume4",
+					Resources: api.ResourceRequirements{
+						Requests: getResourceList("2Gi"),
+					},
+					StorageClassName: &silverClassName,
+				},
+				Status: api.PersistentVolumeClaimStatus{
+					Capacity: getResourceList("2Gi"),
+				},
+			},
+			checkError: expectDynamicallyProvisionedError,
+		},
+	}
+
+	ctrl := newPlugin()
+	informerFactory := informers.NewSharedInformerFactory(nil, controller.NoResyncPeriodFunc())
+	ctrl.SetInternalKubeInformerFactory(informerFactory)
+	err := ctrl.Validate()
+	if err != nil {
+		t.Fatalf("neither pv lister nor storageclass lister can be nil")
+	}
+
+	pv1 := &api.PersistentVolume{
+		ObjectMeta: metav1.ObjectMeta{Name: "volume1"},
+		Spec: api.PersistentVolumeSpec{
+			PersistentVolumeSource: api.PersistentVolumeSource{
+				Glusterfs: &api.GlusterfsVolumeSource{
+					EndpointsName: "http://localhost:8080/",
+					Path:          "/heketi",
+					ReadOnly:      false,
+				},
+			},
+			StorageClassName: goldClassName,
+		},
+	}
+	pv2 := &api.PersistentVolume{
+		ObjectMeta: metav1.ObjectMeta{Name: "volume2"},
+		Spec: api.PersistentVolumeSpec{
+			PersistentVolumeSource: api.PersistentVolumeSource{
+				HostPath: &api.HostPathVolumeSource{},
+			},
+			StorageClassName: goldClassName,
+		},
+	}
+
+	pvs := []*api.PersistentVolume{}
+	pvs = append(pvs, pv1, pv2)
+
+	for _, pv := range pvs {
+		err := informerFactory.Core().InternalVersion().PersistentVolumes().Informer().GetStore().Add(pv)
+		if err != nil {
+			fmt.Println("add pv error: ", err)
+		}
+	}
+
+	scs := []*storage.StorageClass{}
+	scs = append(scs, goldClass, silverClass)
+	for _, sc := range scs {
+		err := informerFactory.Storage().InternalVersion().StorageClasses().Informer().GetStore().Add(sc)
+		if err != nil {
+			fmt.Println("add storageclass error: ", err)
+		}
+	}
+
+	for _, tc := range tests {
+		operation := admission.Update
+		attributes := admission.NewAttributesRecord(tc.newObj, tc.oldObj, schema.GroupVersionKind{}, metav1.NamespaceDefault, "foo", tc.resource, tc.subresource, operation, nil)
+
+		err := ctrl.Admit(attributes)
+		fmt.Println(tc.name)
+		fmt.Println(err)
+		if !tc.checkError(err) {
+			t.Errorf("%v: unexpected err: %v", tc.name, err)
+		}
+	}
+
+}

plugin/pkg/auth/authorizer/rbac/bootstrappolicy/controller_policy.go

@@ -22,7 +22,9 @@ import (
 	"github.com/golang/glog"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	rbac "k8s.io/kubernetes/pkg/apis/rbac"
+	"k8s.io/kubernetes/pkg/features"
 )
 
 const saRolePrefix = "system:controller:"
@@ -121,6 +123,23 @@ func buildControllerRoles() ([]rbac.ClusterRole, []rbac.ClusterRoleBinding) {
 			eventsRule(),
 		},
 	})
+
+	if utilfeature.DefaultFeatureGate.Enabled(features.ExpandPersistentVolumes) {
+		addControllerRole(&controllerRoles, &controllerRoleBindings, rbac.ClusterRole{
+			ObjectMeta: metav1.ObjectMeta{Name: saRolePrefix + "expand-controller"},
+			Rules: []rbac.PolicyRule{
+				rbac.NewRule("get", "list", "watch", "update", "patch").Groups(legacyGroup).Resources("persistentvolumes").RuleOrDie(),
+				rbac.NewRule("update", "patch").Groups(legacyGroup).Resources("persistentvolumeclaims/status").RuleOrDie(),
+				rbac.NewRule("get", "list", "watch").Groups(legacyGroup).Resources("persistentvolumeclaims").RuleOrDie(),
+				// glusterfs
+				rbac.NewRule("get", "list", "watch").Groups(storageGroup).Resources("storageclasses").RuleOrDie(),
+				rbac.NewRule("get").Groups(legacyGroup).Resources("services", "endpoints").RuleOrDie(),
+				rbac.NewRule("get").Groups(legacyGroup).Resources("secrets").RuleOrDie(),
+				eventsRule(),
+			},
+		})
+	}
+
 	addControllerRole(&controllerRoles, &controllerRoleBindings, rbac.ClusterRole{
 		ObjectMeta: metav1.ObjectMeta{Name: saRolePrefix + "generic-garbage-collector"},
 		Rules: []rbac.PolicyRule{

staging/src/k8s.io/api/core/v1/generated.proto

@@ -2133,6 +2133,31 @@ message PersistentVolumeClaim {
   optional PersistentVolumeClaimStatus status = 3;
 }
 
+// PersistentVolumeClaimCondition contails details about state of pvc
+message PersistentVolumeClaimCondition {
+  optional string type = 1;
+
+  optional string status = 2;
+
+  // Last time we probed the condition.
+  // +optional
+  optional k8s.io.apimachinery.pkg.apis.meta.v1.Time lastProbeTime = 3;
+
+  // Last time the condition transitioned from one status to another.
+  // +optional
+  optional k8s.io.apimachinery.pkg.apis.meta.v1.Time lastTransitionTime = 4;
+
+  // Unique, this should be a short, machine understandable string that gives the reason
+  // for condition's last transition. If it reports "ResizeStarted" that means the underlying
+  // persistent volume is being resized.
+  // +optional
+  optional string reason = 5;
+
+  // Human-readable message indicating details about last transition.
+  // +optional
+  optional string message = 6;
+}
+
 // PersistentVolumeClaimList is a list of PersistentVolumeClaim items.
 message PersistentVolumeClaimList {
   // Standard list metadata.
@@ -2186,6 +2211,13 @@ message PersistentVolumeClaimStatus {
   // Represents the actual resources of the underlying volume.
   // +optional
   map<string, k8s.io.apimachinery.pkg.api.resource.Quantity> capacity = 3;
+
+  // Current Condition of persistent volume claim. If underlying persistent volume is being
+  // resized then the Condition will be set to 'ResizeStarted'.
+  // +optional
+  // +patchMergeKey=type
+  // +patchStrategy=merge
+  repeated PersistentVolumeClaimCondition conditions = 4;
 }
 
 // PersistentVolumeClaimVolumeSource references the user's PVC in the same namespace.

staging/src/k8s.io/api/core/v1/types.go

@@ -630,6 +630,34 @@ type PersistentVolumeClaimSpec struct {
 	StorageClassName *string `json:"storageClassName,omitempty" protobuf:"bytes,5,opt,name=storageClassName"`
 }
 
+// PersistentVolumeClaimConditionType is a valid value of PersistentVolumeClaimCondition.Type
+type PersistentVolumeClaimConditionType string
+
+const (
+	// PersistentVolumeClaimResizing - a user trigger resize of pvc has been started
+	PersistentVolumeClaimResizing PersistentVolumeClaimConditionType = "Resizing"
+)
+
+// PersistentVolumeClaimCondition contails details about state of pvc
+type PersistentVolumeClaimCondition struct {
+	Type   PersistentVolumeClaimConditionType `json:"type" protobuf:"bytes,1,opt,name=type,casttype=PersistentVolumeClaimConditionType"`
+	Status ConditionStatus                    `json:"status" protobuf:"bytes,2,opt,name=status,casttype=ConditionStatus"`
+	// Last time we probed the condition.
+	// +optional
+	LastProbeTime metav1.Time `json:"lastProbeTime,omitempty" protobuf:"bytes,3,opt,name=lastProbeTime"`
+	// Last time the condition transitioned from one status to another.
+	// +optional
+	LastTransitionTime metav1.Time `json:"lastTransitionTime,omitempty" protobuf:"bytes,4,opt,name=lastTransitionTime"`
+	// Unique, this should be a short, machine understandable string that gives the reason
+	// for condition's last transition. If it reports "ResizeStarted" that means the underlying
+	// persistent volume is being resized.
+	// +optional
+	Reason string `json:"reason,omitempty" protobuf:"bytes,5,opt,name=reason"`
+	// Human-readable message indicating details about last transition.
+	// +optional
+	Message string `json:"message,omitempty" protobuf:"bytes,6,opt,name=message"`
+}
+
 // PersistentVolumeClaimStatus is the current status of a persistent volume claim.
 type PersistentVolumeClaimStatus struct {
 	// Phase represents the current phase of PersistentVolumeClaim.
@@ -642,6 +670,12 @@ type PersistentVolumeClaimStatus struct {
 	// Represents the actual resources of the underlying volume.
 	// +optional
 	Capacity ResourceList `json:"capacity,omitempty" protobuf:"bytes,3,rep,name=capacity,casttype=ResourceList,castkey=ResourceName"`
+	// Current Condition of persistent volume claim. If underlying persistent volume is being
+	// resized then the Condition will be set to 'ResizeStarted'.
+	// +optional
+	// +patchMergeKey=type
+	// +patchStrategy=merge
+	Conditions []PersistentVolumeClaimCondition `json:"conditions,omitempty" patchStrategy:"merge" patchMergeKey:"type" protobuf:"bytes,4,rep,name=conditions"`
 }
 
 type PersistentVolumeAccessMode string

staging/src/k8s.io/api/core/v1/types_swagger_doc_generated.go

@@ -1122,6 +1122,18 @@ func (PersistentVolumeClaim) SwaggerDoc() map[string]string {
 	return map_PersistentVolumeClaim
 }
 
+var map_PersistentVolumeClaimCondition = map[string]string{
+	"":                   "PersistentVolumeClaimCondition contails details about state of pvc",
+	"lastProbeTime":      "Last time we probed the condition.",
+	"lastTransitionTime": "Last time the condition transitioned from one status to another.",
+	"reason":             "Unique, this should be a short, machine understandable string that gives the reason for condition's last transition. If it reports \"ResizeStarted\" that means the underlying persistent volume is being resized.",
+	"message":            "Human-readable message indicating details about last transition.",
+}
+
+func (PersistentVolumeClaimCondition) SwaggerDoc() map[string]string {
+	return map_PersistentVolumeClaimCondition
+}
+
 var map_PersistentVolumeClaimList = map[string]string{
 	"":         "PersistentVolumeClaimList is a list of PersistentVolumeClaim items.",
 	"metadata": "Standard list metadata. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#types-kinds",
@@ -1150,6 +1162,7 @@ var map_PersistentVolumeClaimStatus = map[string]string{
 	"phase":       "Phase represents the current phase of PersistentVolumeClaim.",
 	"accessModes": "AccessModes contains the actual access modes the volume backing the PVC has. More info: https://kubernetes.io/docs/concepts/storage/persistent-volumes#access-modes-1",
 	"capacity":    "Represents the actual resources of the underlying volume.",
+	"conditions":  "Current Condition of persistent volume claim. If underlying persistent volume is being resized then the Condition will be set to 'ResizeStarted'.",
 }
 
 func (PersistentVolumeClaimStatus) SwaggerDoc() map[string]string {

staging/src/k8s.io/api/core/v1/zz_generated.deepcopy.go

@@ -428,6 +428,10 @@ func RegisterDeepCopies(scheme *runtime.Scheme) error {
 			return nil
 		}, InType: reflect.TypeOf(&PersistentVolumeClaim{})},
 		conversion.GeneratedDeepCopyFunc{Fn: func(in interface{}, out interface{}, c *conversion.Cloner) error {
+			in.(*PersistentVolumeClaimCondition).DeepCopyInto(out.(*PersistentVolumeClaimCondition))
+			return nil
+		}, InType: reflect.TypeOf(&PersistentVolumeClaimCondition{})},
+		conversion.GeneratedDeepCopyFunc{Fn: func(in interface{}, out interface{}, c *conversion.Cloner) error {
 			in.(*PersistentVolumeClaimList).DeepCopyInto(out.(*PersistentVolumeClaimList))
 			return nil
 		}, InType: reflect.TypeOf(&PersistentVolumeClaimList{})},
@@ -3500,6 +3504,24 @@ func (in *PersistentVolumeClaim) DeepCopyObject() runtime.Object {
 }
 
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *PersistentVolumeClaimCondition) DeepCopyInto(out *PersistentVolumeClaimCondition) {
+	*out = *in
+	in.LastProbeTime.DeepCopyInto(&out.LastProbeTime)
+	in.LastTransitionTime.DeepCopyInto(&out.LastTransitionTime)
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new PersistentVolumeClaimCondition.
+func (in *PersistentVolumeClaimCondition) DeepCopy() *PersistentVolumeClaimCondition {
+	if in == nil {
+		return nil
+	}
+	out := new(PersistentVolumeClaimCondition)
+	in.DeepCopyInto(out)
+	return out
+}
+
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *PersistentVolumeClaimList) DeepCopyInto(out *PersistentVolumeClaimList) {
 	*out = *in
 	out.TypeMeta = in.TypeMeta
@@ -3588,6 +3610,13 @@ func (in *PersistentVolumeClaimStatus) DeepCopyInto(out *PersistentVolumeClaimSt
 			(*out)[key] = val.DeepCopy()
 		}
 	}
+	if in.Conditions != nil {
+		in, out := &in.Conditions, &out.Conditions
+		*out = make([]PersistentVolumeClaimCondition, len(*in))
+		for i := range *in {
+			(*in)[i].DeepCopyInto(&(*out)[i])
+		}
+	}
 	return
 }
 

staging/src/k8s.io/api/storage/v1/generated.pb.go

@@ -136,6 +136,16 @@ func (m *StorageClass) MarshalTo(dAtA []byte) (int, error) {
 			i += copy(dAtA[i:], s)
 		}
 	}
+	if m.AllowVolumeExpansion != nil {
+		dAtA[i] = 0x30
+		i++
+		if *m.AllowVolumeExpansion {
+			dAtA[i] = 1
+		} else {
+			dAtA[i] = 0
+		}
+		i++
+	}
 	return i, nil
 }
 
@@ -229,6 +239,9 @@ func (m *StorageClass) Size() (n int) {
 			n += 1 + l + sovGenerated(uint64(l))
 		}
 	}
+	if m.AllowVolumeExpansion != nil {
+		n += 2
+	}
 	return n
 }
 
@@ -279,6 +292,7 @@ func (this *StorageClass) String() string {
 		`Parameters:` + mapStringForParameters + `,`,
 		`ReclaimPolicy:` + valueToStringGenerated(this.ReclaimPolicy) + `,`,
 		`MountOptions:` + fmt.Sprintf("%v", this.MountOptions) + `,`,
+		`AllowVolumeExpansion:` + valueToStringGenerated(this.AllowVolumeExpansion) + `,`,
 		`}`,
 	}, "")
 	return s
@@ -565,6 +579,27 @@ func (m *StorageClass) Unmarshal(dAtA []byte) error {
 			}
 			m.MountOptions = append(m.MountOptions, string(dAtA[iNdEx:postIndex]))
 			iNdEx = postIndex
+		case 6:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field AllowVolumeExpansion", wireType)
+			}
+			var v int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowGenerated
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				v |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			b := bool(v != 0)
+			m.AllowVolumeExpansion = &b
 		default:
 			iNdEx = preIndex
 			skippy, err := skipGenerated(dAtA[iNdEx:])
@@ -807,40 +842,43 @@ func init() {
 }
 
 var fileDescriptorGenerated = []byte{
-	// 558 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x8c, 0x52, 0xcd, 0x6e, 0xd3, 0x40,
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-	0xfc, 0x1b, 0x00, 0x00, 0xff, 0xff, 0xbf, 0xb4, 0xf1, 0xb4, 0x62, 0x04, 0x00, 0x00,
+	// 593 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x8c, 0x92, 0x41, 0x6f, 0xd3, 0x3e,
+	0x18, 0xc6, 0x9b, 0x76, 0xfd, 0x6b, 0x73, 0x37, 0xfd, 0xab, 0x30, 0xa4, 0xa8, 0x87, 0xb4, 0x1a,
+	0x97, 0x0a, 0x09, 0x7b, 0xdd, 0x06, 0x9a, 0x90, 0x40, 0xa2, 0x68, 0x12, 0x48, 0x9b, 0x56, 0x05,
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+	0x00,
 }

staging/src/k8s.io/api/storage/v1/generated.proto

@@ -59,6 +59,10 @@ message StorageClass {
   // mount of the PVs will simply fail if one is invalid.
   // +optional
   repeated string mountOptions = 5;
+
+  // AllowVolumeExpansion shows whether the storage class allow volume expand
+  // +optional
+  optional bool allowVolumeExpansion = 6;
 }
 
 // StorageClassList is a collection of storage classes.

staging/src/k8s.io/api/storage/v1/types.go

@@ -55,6 +55,10 @@ type StorageClass struct {
 	// mount of the PVs will simply fail if one is invalid.
 	// +optional
 	MountOptions []string `json:"mountOptions,omitempty" protobuf:"bytes,5,opt,name=mountOptions"`
+
+	// AllowVolumeExpansion shows whether the storage class allow volume expand
+	// +optional
+	AllowVolumeExpansion *bool `json:"allowVolumeExpansion,omitempty" protobuf:"varint,6,opt,name=allowVolumeExpansion"`
 }
 
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

staging/src/k8s.io/api/storage/v1/types_swagger_doc_generated.go

@@ -28,12 +28,13 @@ package v1
 
 // AUTO-GENERATED FUNCTIONS START HERE
 var map_StorageClass = map[string]string{
-	"":              "StorageClass describes the parameters for a class of storage for which PersistentVolumes can be dynamically provisioned.\n\nStorageClasses are non-namespaced; the name of the storage class according to etcd is in ObjectMeta.Name.",
-	"metadata":      "Standard object's metadata. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#metadata",
-	"provisioner":   "Provisioner indicates the type of the provisioner.",
-	"parameters":    "Parameters holds the parameters for the provisioner that should create volumes of this storage class.",
-	"reclaimPolicy": "Dynamically provisioned PersistentVolumes of this storage class are created with this reclaimPolicy. Defaults to Delete.",
-	"mountOptions":  "Dynamically provisioned PersistentVolumes of this storage class are created with these mountOptions, e.g. [\"ro\", \"soft\"]. Not validated - mount of the PVs will simply fail if one is invalid.",
+	"":                     "StorageClass describes the parameters for a class of storage for which PersistentVolumes can be dynamically provisioned.\n\nStorageClasses are non-namespaced; the name of the storage class according to etcd is in ObjectMeta.Name.",
+	"metadata":             "Standard object's metadata. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#metadata",
+	"provisioner":          "Provisioner indicates the type of the provisioner.",
+	"parameters":           "Parameters holds the parameters for the provisioner that should create volumes of this storage class.",
+	"reclaimPolicy":        "Dynamically provisioned PersistentVolumes of this storage class are created with this reclaimPolicy. Defaults to Delete.",
+	"mountOptions":         "Dynamically provisioned PersistentVolumes of this storage class are created with these mountOptions, e.g. [\"ro\", \"soft\"]. Not validated - mount of the PVs will simply fail if one is invalid.",
+	"allowVolumeExpansion": "AllowVolumeExpansion shows whether the storage class allow volume expand",
 }
 
 func (StorageClass) SwaggerDoc() map[string]string {

staging/src/k8s.io/api/storage/v1/zz_generated.deepcopy.go

@@ -74,6 +74,15 @@ func (in *StorageClass) DeepCopyInto(out *StorageClass) {
 		*out = make([]string, len(*in))
 		copy(*out, *in)
 	}
+	if in.AllowVolumeExpansion != nil {
+		in, out := &in.AllowVolumeExpansion, &out.AllowVolumeExpansion
+		if *in == nil {
+			*out = nil
+		} else {
+			*out = new(bool)
+			**out = **in
+		}
+	}
 	return
 }
 

staging/src/k8s.io/api/storage/v1beta1/generated.pb.go

@@ -136,6 +136,16 @@ func (m *StorageClass) MarshalTo(dAtA []byte) (int, error) {
 			i += copy(dAtA[i:], s)
 		}
 	}
+	if m.AllowVolumeExpansion != nil {
+		dAtA[i] = 0x30
+		i++
+		if *m.AllowVolumeExpansion {
+			dAtA[i] = 1
+		} else {
+			dAtA[i] = 0
+		}
+		i++
+	}
 	return i, nil
 }
 
@@ -229,6 +239,9 @@ func (m *StorageClass) Size() (n int) {
 			n += 1 + l + sovGenerated(uint64(l))
 		}
 	}
+	if m.AllowVolumeExpansion != nil {
+		n += 2
+	}
 	return n
 }
 
@@ -279,6 +292,7 @@ func (this *StorageClass) String() string {
 		`Parameters:` + mapStringForParameters + `,`,
 		`ReclaimPolicy:` + valueToStringGenerated(this.ReclaimPolicy) + `,`,
 		`MountOptions:` + fmt.Sprintf("%v", this.MountOptions) + `,`,
+		`AllowVolumeExpansion:` + valueToStringGenerated(this.AllowVolumeExpansion) + `,`,
 		`}`,
 	}, "")
 	return s
@@ -565,6 +579,27 @@ func (m *StorageClass) Unmarshal(dAtA []byte) error {
 			}
 			m.MountOptions = append(m.MountOptions, string(dAtA[iNdEx:postIndex]))
 			iNdEx = postIndex
+		case 6:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field AllowVolumeExpansion", wireType)
+			}
+			var v int
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowGenerated
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				v |= (int(b) & 0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+			b := bool(v != 0)
+			m.AllowVolumeExpansion = &b
 		default:
 			iNdEx = preIndex
 			skippy, err := skipGenerated(dAtA[iNdEx:])
@@ -807,40 +842,42 @@ func init() {
 }
 
 var fileDescriptorGenerated = []byte{
-	// 554 bytes of a gzipped FileDescriptorProto
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-	0xff, 0xff, 0x2a, 0xfd, 0x7a, 0x0a, 0x73, 0x04, 0x00, 0x00,
+	// 589 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x8c, 0x92, 0x4f, 0x4f, 0xd4, 0x40,
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+	0xe0, 0xfa, 0x9d, 0x88, 0xd2, 0x18, 0x6e, 0x30, 0xde, 0x4d, 0x6f, 0x73, 0x0f, 0xad, 0xc5, 0x22,
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+	0x00, 0x00, 0x00, 0xff, 0xff, 0x1b, 0xae, 0x44, 0x72, 0xc1, 0x04, 0x00, 0x00,
 }

staging/src/k8s.io/api/storage/v1beta1/generated.proto

@@ -59,6 +59,10 @@ message StorageClass {
   // mount of the PVs will simply fail if one is invalid.
   // +optional
   repeated string mountOptions = 5;
+
+  // AllowVolumeExpansion shows whether the storage class allow volume expand
+  // +optional
+  optional bool allowVolumeExpansion = 6;
 }
 
 // StorageClassList is a collection of storage classes.

staging/src/k8s.io/api/storage/v1beta1/types.go

@@ -55,6 +55,10 @@ type StorageClass struct {
 	// mount of the PVs will simply fail if one is invalid.
 	// +optional
 	MountOptions []string `json:"mountOptions,omitempty" protobuf:"bytes,5,opt,name=mountOptions"`
+
+	// AllowVolumeExpansion shows whether the storage class allow volume expand
+	// +optional
+	AllowVolumeExpansion *bool `json:"allowVolumeExpansion,omitempty" protobuf:"varint,6,opt,name=allowVolumeExpansion"`
 }
 
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

staging/src/k8s.io/api/storage/v1beta1/types_swagger_doc_generated.go

@@ -28,12 +28,13 @@ package v1beta1
 
 // AUTO-GENERATED FUNCTIONS START HERE
 var map_StorageClass = map[string]string{
-	"":              "StorageClass describes the parameters for a class of storage for which PersistentVolumes can be dynamically provisioned.\n\nStorageClasses are non-namespaced; the name of the storage class according to etcd is in ObjectMeta.Name.",
-	"metadata":      "Standard object's metadata. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#metadata",
-	"provisioner":   "Provisioner indicates the type of the provisioner.",
-	"parameters":    "Parameters holds the parameters for the provisioner that should create volumes of this storage class.",
-	"reclaimPolicy": "Dynamically provisioned PersistentVolumes of this storage class are created with this reclaimPolicy. Defaults to Delete.",
-	"mountOptions":  "Dynamically provisioned PersistentVolumes of this storage class are created with these mountOptions, e.g. [\"ro\", \"soft\"]. Not validated - mount of the PVs will simply fail if one is invalid.",
+	"":                     "StorageClass describes the parameters for a class of storage for which PersistentVolumes can be dynamically provisioned.\n\nStorageClasses are non-namespaced; the name of the storage class according to etcd is in ObjectMeta.Name.",
+	"metadata":             "Standard object's metadata. More info: https://git.k8s.io/community/contributors/devel/api-conventions.md#metadata",
+	"provisioner":          "Provisioner indicates the type of the provisioner.",
+	"parameters":           "Parameters holds the parameters for the provisioner that should create volumes of this storage class.",
+	"reclaimPolicy":        "Dynamically provisioned PersistentVolumes of this storage class are created with this reclaimPolicy. Defaults to Delete.",
+	"mountOptions":         "Dynamically provisioned PersistentVolumes of this storage class are created with these mountOptions, e.g. [\"ro\", \"soft\"]. Not validated - mount of the PVs will simply fail if one is invalid.",
+	"allowVolumeExpansion": "AllowVolumeExpansion shows whether the storage class allow volume expand",
 }
 
 func (StorageClass) SwaggerDoc() map[string]string {

staging/src/k8s.io/api/storage/v1beta1/zz_generated.deepcopy.go

@@ -74,6 +74,15 @@ func (in *StorageClass) DeepCopyInto(out *StorageClass) {
 		*out = make([]string, len(*in))
 		copy(*out, *in)
 	}
+	if in.AllowVolumeExpansion != nil {
+		in, out := &in.AllowVolumeExpansion, &out.AllowVolumeExpansion
+		if *in == nil {
+			*out = nil
+		} else {
+			*out = new(bool)
+			**out = **in
+		}
+	}
 	return
 }