Ceph

We provide an interface via the Objecter (and librados) for getting the return code of specific ops within a compound operation. Right now, the OSD never fills those in, so they're always set to zero!
This is often appropriate, since most operations fail as soon as one of the individual Ops fail. However, some can be marked as okay to fail, and sometimes we can desire the individual return values (containing, eg, the amount of data read).

A (very small) patch that probably solves the problem is in wip-rval, but before merging we of course need to add tests to detect this problem, and make sure we haven't broken anything else.