Raw block volume GA (#19338)

* Raw block volume GA

Feature BlockVolume reaches GA in 1.17

* Add volumeMode overview

content/en/docs/concepts/storage/persistent-volumes.md

@@ -319,12 +319,24 @@ Currently, storage size is the only resource that can be set or requested.  Futu
 
 ### Volume Mode
 
-{{< feature-state for_k8s_version="v1.13" state="beta" >}}
+{{< feature-state for_k8s_version="v1.18" state="stable" >}}
 
-Prior to Kubernetes 1.9, all volume plugins created a filesystem on the persistent volume.
-Now, you can set the value of `volumeMode` to `block` to use a raw block device, or `filesystem`
-to use a filesystem. `filesystem` is the default if the value is omitted. This is an optional API
-parameter.
+Kubernetes supports two `volumeModes` of PersistentVolumes: `Filesystem` and `Block`.
+
+`volumeMode` is an optional API parameter.
+`Filesystem` is the default mode used when `volumeMode` parameter is omitted.
+
+A volume with `volumeMode: Filesystem` is *mounted* into Pods into a directory. If the volume
+is backed by a block device and the device is empty, Kuberneretes creates a filesystem
+on the device before mounting it for the first time.
+
+You can set the value of `volumeMode` to `Block` to use a volume as a raw block device.
+Such volume is presented into a Pod as a block device, without any filesystem on it.
+This mode is useful to provide a Pod the fastest possible way to access a volume, without
+any filesystem layer between the Pod and the volume. On the other hand, the application
+running in the Pod must know how to handle a raw block device.
+See [Raw Block Volume Support](docs/concepts/storage/persistent-volumes/#raw-block-volume-support)
+for an example on how to use a volume with `volumeMode: Block` in a Pod.
 
 ### Access Modes
 
@@ -559,24 +571,21 @@ spec:
 
 ## Raw Block Volume Support
 
-{{< feature-state for_k8s_version="v1.13" state="beta" >}}
+{{< feature-state for_k8s_version="v1.18" state="stable" >}}
 
 The following volume plugins support raw block volumes, including dynamic provisioning where
 applicable:
 
 * AWSElasticBlockStore
 * AzureDisk
+* CSI
 * FC (Fibre Channel)
 * GCEPersistentDisk
 * iSCSI
 * Local volume
+* OpenStack Cinder
 * RBD (Ceph Block Device)
-* VsphereVolume (alpha)
-
-{{< note >}}
-Only FC and iSCSI volumes supported raw block volumes in Kubernetes 1.9.
-Support for the additional plugins was added in 1.10.
-{{< /note >}}
+* VsphereVolume
 
 ### Persistent Volumes using a Raw Block Volume
 

content/en/docs/concepts/storage/volumes.md

@@ -1302,19 +1302,13 @@ persistent volume:
 
 #### CSI raw block volume support
 
-{{< feature-state for_k8s_version="v1.14" state="beta" >}}
+{{< feature-state for_k8s_version="v1.18" state="stable" >}}
 
-Starting with version 1.11, CSI introduced support for raw block volumes, which
-relies on the raw block volume feature that was introduced in a previous version of
-Kubernetes.  This feature will make it possible for vendors with external CSI drivers to
-implement raw block volumes support in Kubernetes workloads.
+Vendors with external CSI drivers can implement raw block volumes support
+in Kubernetes workloads.
 
-CSI block volume support is feature-gated, but enabled by default. The two
-feature gates which must be enabled for this feature are `BlockVolume` and
-`CSIBlockVolume`.
-
-Learn how to
-[setup your PV/PVC with raw block volume support](/docs/concepts/storage/persistent-volumes/#raw-block-volume-support).
+You can [setup your PV/PVC with raw block volume support](/docs/concepts/storage/persistent-volumes/#raw-block-volume-support)
+as usual, without any CSI specific changes.
 
 #### CSI ephemeral volumes