Re: [Qemu-devel] [PATCH v20 06/15] block: Add backing_blocker in BlockDriverState

[Jeff Cody]

On Wed, May 21, 2014 at 04:03:03PM +0200, Stefan Hajnoczi wrote:
> On Tue, May 20, 2014 at 02:04:31PM +0800, Fam Zheng wrote:
> > diff --git a/block/mirror.c b/block/mirror.c
> > index 1c38aa8..6a53d79 100644
> > --- a/block/mirror.c
> > +++ b/block/mirror.c
> > @@ -499,6 +499,7 @@ immediate_exit:
> >               * trigger the unref from the top one */
> >              BlockDriverState *p = s->base->backing_hd;
> >              s->base->backing_hd = NULL;
> > +            bdrv_op_unblock_all(p, s->base->backing_blocker);
> >              bdrv_unref(p);
> >          }
> >      }
> 
> Would be cleaner to call bdrv_set_backing_hd(s->base, NULL) here instead
> of open coding it.
>

Patch 10 gets rid of essentially this whole chunk of code, and
replaces it with bdrv_drop_intermediate(). So it does get cleaned up,
just later in the series.