On Mon, Aug 22, 2016 at 3:14 PM, Tom Yan [off-list ref] wrote:

On 23 August 2016 at 03:43, Shaun Tancheff [off-list ref] wrote:

quoted

Why would we enforce upper level limits on something that doesn't
have any?

If we advertise a limit in our SATL, it makes sense that we should
make sure the behaviour is consistent when we issue a write same
through the block layer / ioctl and when we issue a SCSI Write Same
command directly (e.g. with sg_write_same). IMHO that's pretty much
why SBC would mandate such behaviour as well.

Breaking would be advertising a limit that is too high and failing.
Advertising a lower limit and succeeding may not be ideal for all
possible use cases, but it's not breaking behaviour.

quoted

If the upper level, or SG_IO, chooses to set a timeout of 10 hours and
wipe a whole disk it should be free to do so.

That's why I said, "if you are going to advertise an Maximum Write Same Length".

-- 
Shaun Tancheff