Is this a BUG REPORT or FEATURE REQUEST?:
@kubernetes/sig-storage-bugs

What happened:
Bug #56081 thought that PD allocates in GB, perhaps based on the API definition which says GB, but didn't define what GB actually is. But actually, PD allocates in GiB.

I manually created a PD in GB, and manually attached it to a node:

$ gcloud compute disks create msau-test --zone=us-central1-b --size=1GB

Ran lsblk on it, and it shows the bytes of the disk are 1GiB:

$ lsblk -b
sdc       8:32   0  1073741824  0 disk 

What you expected to happen:
I think we need to revert #56600 (and maybe a few other e2e changes that went in afterwards), and make sure the GCE cloud provider returns disk size in GiB.