provider/openstack: blockstorage volume attach code review updates

builtin/providers/openstack/resource_openstack_blockstorage_volume_attach_v2.go

@@ -16,7 +16,6 @@ func resourceBlockStorageVolumeAttachV2() *schema.Resource {
 	return &schema.Resource{
 		Create: resourceBlockStorageVolumeAttachV2Create,
 		Read:   resourceBlockStorageVolumeAttachV2Read,
-		Update: nil,
 		Delete: resourceBlockStorageVolumeAttachV2Delete,
 		Importer: &schema.ResourceImporter{
 			State: schema.ImportStatePassthrough,
@@ -233,6 +232,7 @@ func blockStorageVolumeAttachV2AttachMode(v string) (volumeactions.AttachMode, e
 	var attachError error
 	switch v {
 	case "":
+		attachMode = ""
 	case "ro":
 		attachMode = volumeactions.ReadOnly
 	case "rw":

website/source/docs/providers/openstack/r/blockstorage_volume_attach_v2.html.markdown

@@ -53,6 +53,7 @@ The following arguments are supported:
 
 * `attach_mode` - (Optional) Specify whether to attach the volume as Read-Only
   (`ro`) or Read-Write (`rw`). Only values of `ro` and `rw` are accepted.
+  If left unspecified, the Block Storage API will apply a default of `rw`.
 
 ## Attributes Reference