On Wed, Jul 17, 2013 at 10:02 AM, Peter Lieven <p...@kamp.de> wrote: > For Disks we always use read/write16 so i think we Should also use > writesame16. Or not?
Sounds good. > > Von meinem iPhone gesendet > > Am 17.07.2013 um 18:31 schrieb ronnie sahlberg <ronniesahlb...@gmail.com>: > >> On Wed, Jul 17, 2013 at 9:27 AM, Paolo Bonzini <pbonz...@redhat.com> wrote: >>> Il 17/07/2013 17:54, ronnie sahlberg ha scritto: >>>> I think it is reasonable to assume that IF LBPRZ==1 and IF it is an >>>> "optimal unmap request" then the blocks will become unmapped and they >>>> will read back as 0. >>> >>> Yes, but it is not reasonable to assume that bdrv_discard will only >>> receive "optimal" requests. Thus, using WRITE SAME for LBPRZ=1, and not >>> exposing LBPRZ=1 if LBPWS=0 (may also use LBPWS10 depending on the >>> capacity), is the safer thing to do. >>> >>> Paolo >> >> ACK. >> >> WRITESAME10/16 with UNMAP flag set is probably best.
