Re: [PATCH v8 6/7] sd: Implement support for ZBC devices

[Jeff Moyer <jmoyer@redhat.com>]

"Martin K. Petersen" <martin.petersen@oracle.com> writes:

>>>>>> "Jeff" == Jeff Moyer <jmoyer@redhat.com> writes:
>
> Jeff,
>
> Jeff> Are power of 2 zone sizes required by the standard?  I see why
> Jeff> you've done this, but I wonder if we're artificially limiting the
> Jeff> implementation, and whether there will be valid devices on the
> Jeff> market that simply won't work with Linux because of this.
>
> Standards are deliberately written to be permissive. But Linux doesn't
> support arbitrary sector sizes either even though the spec allows it. We
> always pick a reasonably sane subset of features to implement and this
> case is no different.
>
> After some discussion we decided to rip out all the complexity that was
> required to facilitate crazy drive layouts. As a result, the code is now
> in a state where we can actually merge it. The hope is that by picking a
> specific configuration subset and widely advertising it we can influence
> the market.
>
> Also, I am not aware of anybody actually asking the drive vendors to
> support crazy zone configurations.

That's fine with me.  I didn't see any mention of this design decision
in the patch logs, though, and given that I'm not intimately involved, I
asked the question.

Thanks,
Jeff