nova should use quota_details neutron api to validate available ports before VM creation

[Ihar Hrachyshka]

Originally reported at https://bugzilla.redhat.com/show_bug.cgi?id=2222102

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When nova creates a VM, it issues a request to fetch all ports for the project, which may take a significant time and even time out.

The code in https://github.com/openstack/nova/blob/master/nova/network/neutron.py#L2654 suggests that nova fetches IDs of all project ports just to count the number of ports in db and compare it to quota (to pre-validate that there's enough free ports to allocate for the request).

Instead of fetching all IDs via get_ports, nova should attempt to use quota_details API that gives ready access to info on available ports:

https://docs.openstack.org/api-ref/network/v2/?expanded=list-quotas-for-projects-with-non-default-quota-values-detail,show-quota-details-for-a-tenant-detail#quotas-details-extension-quota-details

Note that this is an API extension and was added later than the original `quota` API, so it may be that special care should be taken to accommodate to neutron-servers with no such extension.

Also, the extension seems to be controlled by the cfg.CONF.QUOTAS.quota_driver
 config option: https://github.com/openstack/neutron/blob/6fa9142ced0eed8de9a89042747438b93de7202d/neutron/extensions/quotasv2_detail.py#L37

Which means that there may be an (upstream) configuration that would end up with quota_details API missing. So a fallback mechanism may be due.

Side note: it may be argued that neutron should not expose this config option in the first place. This bz doesn't attempt to address this request.