It's possible to set "X-Container-Meta-Quota-Bytes" and "X-Container-Meta-Quota-Count" on containers, as documented in the official docs. It's currently possible to configure quotas on Accounts for "quota-bytes", as documented here. There's currently no way to configure an account quota limit for number of files, or "quota-count". Because of this, a user could possibly exhaust the filesystem inodes.
The code should include a way for users with ResellerAdmin role to add a quota-count limit on accounts, and enforce such limit.
Contact: mpasserini on IRC