On Thu, Dec 18, 2008 at 11:05:54AM +0200, Boaz Harrosh wrote: > Matthew Wilcox wrote: > >>> Algorithm B: > >>> > >>> Issue RC10 > >>> Issue RC16 > >>> -> If it succeeds, use its results in preference to those from RC10 > >>> -> If it fails, carry on with the results from RC10 > >>> -> If it times out, reset the device, carry on with the results from RC10 > >> I fail to see an effective difference between Algo A and B. > > > > Whether to issue an RC10 before issuing an RC16 or not. It matches what > > we currently do better (we currently issue an RC10 and then issue an > > RC16 if RC10 reports we have 0xffffffff LBAs). > > > > Sorry to barge in but I think this is the most practical solution and the one > to go to T10 with. > > If a (new) device supports RC16 it should return LBAs==0xffffffff for RC10 even > if it's capacity is smaller, to indicate an RC16 request. That breaks compatibility with older software that doesn't know that RC16 exists. > If LBAs!=0xffffffff and !SCSI_3 then do not risk RC16 unless a white list > or load parameter. > > Since you are going to T10 with this the white list should be, as you said > in other mail, zero length. I don't need to go to T10 for anything except Algorithm D. -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step." -- 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
