A simple fstrim on a thin-provisioned drive is returning "Not Supported" error on my machine SLES12 SP2. The drive in question supports SCSI UNMAP requests but the kernel logs reveal that it is actually sending WRITE_SAME(16) instead. Is this configurable by any means? I tried XFS and ext3. A lot of online documentation states that it is supposed to send UNMAP request. I'm trying to trace the request to understand more but any help would be appreciated!