Re: [Qemu-devel] [RFC 2/7] sd.c: introduce variable for trekking valid data

[Stefan Hajnoczi <stefanha@gmail.com>]

On Fri, Jun 14, 2013 at 12:49:52PM +0100, Peter Maydell wrote:
> On 10 May 2013 17:10, Igor Mitsyanko <i.mitsyanko@gmail.com> wrote:
> > Initialize it appropriately when various commands are processed.
> 
> "tracking", but the commit message doesn't match the
> patch contents anyway -- should this patch have more
> content from later patches, or be squashed into one of
> them?
> 
> >
> > Signed-off-by: Igor Mitsyanko <i.mitsyanko@gmail.com>
> > ---
> >  hw/sd/sd.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/hw/sd/sd.c b/hw/sd/sd.c
> > index 1dd1331..775a55c 100644
> > --- a/hw/sd/sd.c
> > +++ b/hw/sd/sd.c
> > @@ -116,6 +116,7 @@ struct SDState {
> >      QEMUIOVector qiov;
> >      struct iovec iov;
> >      BlockDriverAIOCB *aiocb;
> > +    uint32_t transf_cnt;
> 
> How does this work for migration -- are we guaranteed that
> all outstanding AIO requests complete before we try to
> migrate?

Migration does bdrv_drain_all() to complete all pending requests
(indirectly by pausing the guest in do_vm_stop()).

Stefan