Re: [PATCH 0/6] ZAC host-aware device support

[Hannes Reinecke <hare@suse.de>]

On 08/02/2015 06:11 PM, James Bottomley wrote:
> On Fri, 2015-07-31 at 15:02 +0200, Hannes Reinecke wrote:
>> Hi all,
>>
>> here is a patchset for adding ZAC host-aware device support to libata.
>> Main bits are translations for ZBC IN and ZBC OUT; others are the
>> required plumbing like generating the correct VPD pages.
>> James, do you require a separate patch for adding ZBC IN and ZBC OUT
>> or is it okay to have it queued here?
> 
> This really belongs in the ZBC patch set, doesn't it? Why isn't it
> there.  You can't avoid the dependency.  If it goes with the ZAC patch
> set, then the ZBC one depends on ZAC.  If it goes properly with ZBC then
> you need an additional patch adding the ATA translations after the ZBC
> one.  On the whole, I'd prefer the latter so we always have the required
> consumers of the API.
> 
> In fact, if I read the dependencies correctly, you need the ZBC patches
> first, don't you ... otherwise there's nothing to drive host aware ZAC?
> 
No. These patches just implement a proper SATL for ZAC drives.
So in effect they just bring libata support on par with 'real' ZBC
drives, allowing things like 'sg_rep_zones' to work properly there.

As such I've considered those patches to be a precursor for ZBC support.

But then, I don't mind how it's being handled.
I surely can turn things around, ZBC support first, and ZAC as an
add-on to that.
Just say the word.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		               zSeries & Storage
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