Re: [PATCH 0/3] block: blk_interposer - Block Layer Interposer

From: Hannes Reinecke
Date: Fri Dec 11 2020 - 13:05:14 EST


On 12/11/20 6:04 PM, Jens Axboe wrote:
On 12/11/20 9:56 AM, Hannes Reinecke wrote:
On 12/11/20 5:33 PM, Jens Axboe wrote:
On 12/11/20 9:30 AM, Mike Snitzer wrote:
While I still think there needs to be a proper _upstream_ consumer of
blk_interposer as a condition of it going in.. I'll let others make the
call.

That's an unequivocal rule.

As such, I'll defer to Jens, Christoph and others on whether your
minimalist blk_interposer hook is acceptable in the near-term.

I don't think so, we don't do short term bandaids just to plan on
ripping that out when the real functionality is there. IMHO, the dm
approach is the way to go - it provides exactly the functionality that
is needed in an appropriate way, instead of hacking some "interposer"
into the core block layer.

Which is my plan, too.

I'll be working with the Veeam folks to present a joint patchset
(including the DM bits) for the next round.

Just to be clear, core block additions for something that dm will
consume is obviously fine. Adding this as block layer functionality than
then exposes an application API for setting it up, tearing down, etc -
that is definitely NOT

That was never my intention.
Any consumers of this thing would need to be in-kernel.
If that was your concern.

Cheers,

Hannes
--
Dr. Hannes Reinecke Kernel Storage Architect
hare@xxxxxxx +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), Geschäftsführer: Felix Imendörffer