>>>>> "James" == James Bottomley <jbottomley@xxxxxxxxxxxxx> writes: James> It's the code we identified in sd.c:read_capacity_16(): That's there to support devices that implement thin provisioning but which predate the LBP VPD page. And thus have no way to tell us their preferred command variant. James> If the inquiry shows LBPME set, we'll do write same regardless of James> the no_write_same bit. That's why for SPC-2 devices it only James> shows up on >> 2TB devices because they force RC16. But we only do so if they have LBPME set. Generally they don't. The problem for hyperv was that LBPME was set. And because it claimed SBC-2 we did not check the LBP VPD page to see that it prefers UNMAP. I believe we did consider unconditionally checking for VPDs when LBPME was set but I seem to recall that it broke some device that had garbage in the READ CAPACITY(16) response. I'll see if I can locate the details. Otherwise I'm willing to entertain that idea. -- Martin K. Petersen Oracle Linux Engineering _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
