Re: [Qemu-devel] [PATCH v5 0/8] Implement reference count for BlockDriverState [resend]

[Fam Zheng]

On Thu, 08/22 13:38, Stefan Hajnoczi wrote:
> On Fri, Aug 09, 2013 at 06:01:53PM +0800, Fam Zheng wrote:
> > [resend to the correct list]
> > 
> > BlockDriverState lifecycle management is needed by future features such as
> > image fleecing and blockdev-add. This series adds reference count to
> > BlockDriverState.
> > 
> > The first two patches clean up two odd BlockDriverState use cases, so all 
> > code
> > uses bdrv_new() to create BlockDriverState instance.
> > 
> > Then implemented bdrv_ref() and bdrv_unref() to operate on refcnt: 
> > Initially,
> > refcnt is 1, which means bdrv_unref is effectively a bdrv_delete() here. So
> > patch 04 has a search and replace to convert bdrv_delete to bdrv_unref, 
> > before
> > bdrv_ref is used anywhere. 05~08 patches calls bdrv_ref for device attach,
> > block-migration and nbd.
> > 
> > The rule is: Either bdrv_ref() or bdrv_new() must have a matching
> > bdrv_unref() call, and the last matching bdrv_unref deletes the bs.
> > 
> > v4:
> >     08: Added, let block job use BDS reference.
> >     02: Fix leak of bs.opaque
> > 
> > v3:
> >     03: Removed unnecessary bdrv_close() call.
> > 
> > v2:
> >     05: Removed: "block: use BlockDriverState refcnt for device 
> > attach/detach"
> >     07: Fix xen_disk blk_disconnect() as it depended on device attach 
> > refcnt.
> 
> Sorry, can't merge this because it breaks qemu-iotests 041 and 055:
> 
>   $ ./check -qcow2 055 041

041 works for me, so I will post v6 to fix 055. If 041 still not working
then, I'll look into it.
> 
> Please always run qemu-iotests before submitting patches.
> 
OK.

Thanks

Fam