>>>>> "James" == James Bottomley <jbottomley@xxxxxxxxxxxxx> writes: James> Well, your judgement: is this situation (support for UNMAP but James> not for WRITE_SAME) in what is effectively a RAID driver (hv James> drivers count as RAID) just a silly Microsoft one off? I only recall seeing one or two devices that supported LBP but not WRITE SAME w/UNMAP. James> However, if we get any RAID drivers with strange discard support, James> we'll likely get the same problem The LBP VPD page is mandatory now. It wasn't for the first couple of generations of devices that we still have to support. I think that if a vendor were to support LBP, adding the mandatory VPD page would be a given. And so far nobody has messed up the LBP VPD page contents. My main gripe about linking no_write_same and discard functionality is that the heuristics for the latter are already excessively complex thanks to having to support devices that predate the spec. I'm wary of adding another dimension to that. Also, linking the two use cases we can get into inconsistent states where no_write_same is set but the device does not support UNMAP and has LBPWS=1 and LBPWS10=1 set in the LBP VPD. I'll contemplate the LBPME => mandatory VPD lookup thing for bit. -- Martin K. Petersen Oracle Linux Engineering -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
