csi: validate volume block has attachment_mode and access_mode

The `attachment_mode` and `access_mode` fields are required for CSI
volumes. The `mount_options` block is only allowed for CSI volumes.

CHANGELOG.md

@@ -1,10 +1,14 @@
 ## 1.1.1 (Unreleased)
 
+IMPROVEMENTS:
+* csi: Validate that `volume` blocks for CSI volumes include the required `attachment_mode` and `access_mode` fields. [[GH-10651](https://github.com/hashicorp/nomad/issues/10651)]
+
 BUG FIXES:
 * api: Fixed event stream connection initialization when there are no events to send [[GH-10637](https://github.com/hashicorp/nomad/issues/10637)]
 * cli: Fixed a bug where `quota status` and `namespace status` commands may panic if the CLI targets a pre-1.1.0 cluster
 * csi: Fixed a bug where `mount_options` were not passed to CSI controller plugins for validation during volume creation and mounting. [[GH-10643](https://github.com/hashicorp/nomad/issues/10643)]
 
+
 ## 1.1.0 (May 18, 2021)
 
 FEATURES:

nomad/structs/volumes.go

@@ -117,6 +117,18 @@ func (v *VolumeRequest) Validate(canaries int) error {
 		mErr.Errors = append(mErr.Errors,
 			fmt.Errorf("host volumes cannot have an access mode"))
 	}
+	if v.Type == VolumeTypeHost && v.MountOptions != nil {
+		mErr.Errors = append(mErr.Errors,
+			fmt.Errorf("host volumes cannot have mount options"))
+	}
+	if v.Type == VolumeTypeCSI && v.AttachmentMode == CSIVolumeAttachmentModeUnknown {
+		mErr.Errors = append(mErr.Errors,
+			fmt.Errorf("CSI volumes must have an attachment mode"))
+	}
+	if v.Type == VolumeTypeCSI && v.AccessMode == CSIVolumeAccessModeUnknown {
+		mErr.Errors = append(mErr.Errors,
+			fmt.Errorf("CSI volumes must have an access mode"))
+	}
 
 	if v.AccessMode == CSIVolumeAccessModeSingleNodeReader || v.AccessMode == CSIVolumeAccessModeMultiNodeReader {
 		if !v.ReadOnly {