>>>>> "Sitsofe" == Sitsofe Wheeler <sits...@yahoo.com> writes:
Sitsofe> The original SCSI WRITE SAME has overloaded semantics - not Sitsofe> only does it mean "write this data multiple times" but it can Sitsofe> also be used to mean "discard this range" too. If the kernel's Sitsofe> command was modelled on the SCSI original perhaps this Sitsofe> conflation clouded things? REQ_WRITE_SAME in the context of the kernel explicitly means "write payload to this block range". A REQ_DISCARD command may be serviced using WRITE SAME(16) with the UNMAP bit set in the SCSI disk driver but that's entirely orthogonal. -- Martin K. Petersen Oracle Linux Engineering
