The patchset looks functionally correct to me, and with a small patch to make use of WRITE_FUA_FLUSH survives xfstests, and instrumenting the underlying qemu shows that we actually get the flush requests where we should. No performance or power fail testing done yet. But I do not like the transition very much. The new WRITE_FUA_FLUSH request is exactly what filesystems expect from a current barrier request, so I'd rather move to that functionality without breaking stuff inbetween. So if it was to me I'd keep patches 1, 2, 4 and 5 from your series, than a main one to relax barrier semantics, then have the renaming patches 7 and 8, and possible keep patch 11 separate from the main implementation change, and if absolutely also a separate one to introduce REQ_FUA and REQ_FLUSH in the bio interface, but keep things working while doing this. Then we can patches do disable the reiserfs barrier "optimization" as the very first one, and DM/MD support which I'm currently working on as the last one and we can start doing the heavy testing. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
