Remove devicemapper storage driver

[kolyshkin]

Fixes: #1619

[kolyshkin]

Surely, we'll need a new major version after this PR.

[rhatdan]

I think we would need to go to podman 5.0 before we merge this in.

[TomSweeneyRedHat]

Thoughts on migration from v4.0 to v5.0 when/if this comes into play?

[kolyshkin]

I think we would need to go to podman 5.0 before we merge this in.

Podman is not compiling in devmapper driver since v0.9.2 (containers/podman#1445). The driver can be compiled in (I checked that), but no one knows if it works at all (I haven't checked).

[rhatdan]

Yes I agree this is not an issue for Podman. So I say we move forward on removing it.

[kolyshkin]

Need to remove it from the major users first:

• podman: is not compiling in devicemapper since v0.9.2 (do not build with devicemapper podman#1445).
• cri-o: Deprecate and remove device mapper storage driver cri-o/cri-o#7002 / Remove device mapper storage driver support cri-o/cri-o#7003
• buildah: Remove device mapper support buildah#4832

[giuseppe]

Podman 5.0 is out, should we get this change in now?

[kolyshkin]

Currently, the only user is cri-o, so it needs to be removed from it first.

The biggest roadblock seems to be cri-o/cri-o#7003 (comment). It's hard to tell if there are cri-o users who use devmapper (I hope not, but I don't know how to verify it). @haircommander maybe you can shed some light?

[rhatdan]

I would be shocked if there were any. Only possible way would be on an ancient 3.11 version, which will never get a new containers/storage version.

[haircommander]

@fidencio @littlejawa last I remembered there was a kata case for devmapper, are we still using it there?

[littlejawa]

Talked with @fidencio about this - it seems our dependency is gone. We have an alternative to device mapper, so it can be removed.

[kolyshkin]

Talked with @fidencio about this - it seems our dependency is gone. We have an alternative to device mapper, so it can be removed.

Awesome! I will revive this

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: kolyshkin, saschagrunert

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [saschagrunert]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[rhatdan]

/lgtm

[rhatdan]

@rhvgoyal The end of an era