[RFC 00/11] DAX fsynx/msync support

[Jeff Moyer]

Jeff Moyer <jmoyer at redhat.com> writes:

>> Hence once the filesystem has waited on the REQ_WRITE|REQ_FLUSH IO
>> to complete, we know that all the earlier REQ_WRITE IOs are on
>> stable storage, too. Hence there's no need for the elevator to drain
>> the queue to guarantee completion ordering - the dispatch ordering
>> and flush/fua write semantics guarantee that when the flush/fua
>> completes, all the IOs dispatch prior to that flush/fua write are
>> also on stable storage...
>
> Des xfs rely on this model for correctness?  If so, I'd say we've got a
> problem.

Dave?