switch block layer polling to a bio based model v4

Tue Jun 15 09:06:19 PDT 2021

On Tue, Jun 15, 2021 at 07:37:06AM -0700, Keith Busch wrote:
> On Tue, Jun 15, 2021 at 03:10:18PM +0200, Christoph Hellwig wrote:
> > Chances since v3:
> >  - rebased to the latests for-5.14/block tree
> >  - fix the refcount logic in __blkdev_direct_IO
> >  - split up a patch to make it easier to review
> >  - grab a queue reference in bio_poll
> >  - better document the RCU assumptions in bio_poll
> 
> It still doesn't look like a failover will work when polling through
> pvsync2. We previously discussed that here:
> 
>   https://marc.info/?l=linux-block&m=162100971816071&w=2

Yes, sorry for losing this.  I'll resend with that added after a short
delay to see if anything else needs attention.