Merge pull request #67955 from jsafrane/csi-skip-attach-saad

Automatic merge from submit-queue (batch tested with PRs 68161, 68023, 67909, 67955, 67731). If you want to cherry-pick this change to another branch, please follow the instructions here: https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md.

CSI: skip attach for non-attachable drivers

**What this PR does / why we need it**:
This is implementation of https://github.com/kubernetes/community/pull/2523. CSI volumes that don't need attach/detach now don't need external attacher running.

WIP:
 * contains #67803 to get CSIDriver API. Ignore the first commit.
 * ~~missing e2e test~~

/sig storage

cc: @saad-ali @vladimirvivien @verult @msau42 @gnufied @davidz627 

**Release note**:
```release-note
CSI volume plugin does not need external attacher for non-attachable CSI volumes.
```

pkg/features/kube_features.go

@@ -386,6 +386,10 @@ const (
 	//
 	// Allow TTL controller to clean up Pods and Jobs after they finish.
 	TTLAfterFinished utilfeature.Feature = "TTLAfterFinished"
+	// owner: @jsafrane
+	// Kubernetes skips attaching CSI volumes that don't require attachment.
+	//
+	CSISkipAttach utilfeature.Feature = "CSISkipAttach"
 )
 
 func init() {
@@ -451,6 +455,7 @@ var defaultKubernetesFeatureGates = map[utilfeature.Feature]utilfeature.FeatureS
 	VolumeSnapshotDataSource:                    {Default: false, PreRelease: utilfeature.Alpha},
 	ProcMountType:                               {Default: false, PreRelease: utilfeature.Alpha},
 	TTLAfterFinished:                            {Default: false, PreRelease: utilfeature.Alpha},
+	CSISkipAttach:                               {Default: false, PreRelease: utilfeature.Alpha},
 
 	// inherited features from generic apiserver, relisted here to get a conflict if it is changed
 	// unintentionally on either side: