allow SINGLE_WRITER to support ReadWriteOncePod

[ddollar]

I'm trying to use the ReadWriteOncePod access mode for a PersistentVolumeClaim

This should be exactly like ReadWriteOnce but can only be mounted once per pod. With ReadWriteOnce two pods on the same node could both write to the same volume, which would be not a good thing for many use cases such as databases.

I tried making this change and rolling a custom civo-csi image in my Civo cluster but I got the following error when trying to create the PVC

Warning  ProvisioningFailed    12s (x5 over 27s)  csi.civo.com_civo-csi-controller-0_48a8b16a-4214-4849-b034-61fc2c4e7a6e  failed to provision volume with StorageClass "civo-volume": rpc error: code = InvalidArgument desc = CreateVolume access mode isn't supported

[davenull]

This change seems appropriate after looking at it in context. I will pass this up to the team and make sure there is nothing else we need to change to make this work properly, but I don't see much that this can affect negatively at the moment. Thank you for the PR!

[hlts2]

Hi @ddollar , thank you for creating this PR. I’ve reviewed the code changes, and they look fine. Therefore, I have approved this PR—thank you!

Regarding the error you encountered, resolving it will require updating the versions of some dependent plugins. This will need separate testing, so please bear with us a little while longer until a fix is ready. Thank you!