Re: [Qemu-devel] [PATCH V4 0/3] Block migration if any of the block device is busy

[Stefan Hajnoczi <stefanha@gmail.com>]

On Mon, Jul 23, 2012 at 3:22 PM,  <benoit.canet@gmail.com> wrote:
> From: Benoît Canet <benoit@irqsave.net>
>
> This patchset is designed to avoid starting a live migration while any of
> the block device is busy.
>
> Tested with the following sequence:
>
> QEMU 1.1.50 monitor - type 'help' for more information
> (qemu) block_stream virtio0 1k
> (qemu) migrate tcp:localhost:4444
> migrate: Migration is blocked by streaming
> (qemu)  block_job_cancel virtio0
> (qemu)  migrate tcp:localhost:4444
> migrate: Connection can not be completed immediately
> (qemu)
> => migration then succeed
>
> in v2:
> stefanha: Rename bdrv_have_block_jobs() to bdrv_are_busy() and make it return -EBUSY.
> paolo: remove spurious bdrv_close()
>
> in v3
> pm215: rewrite confusing error message
>
> in v4:
> stefanha: make the error message more general
>
> Benoît Canet (3):
>   block: Add bdrv_are_busy()
>   qerror: Add error telling that block dev usage prevents migration
>   migration: block migration when streaming block jobs are running.
>
>  block.c     |   13 +++++++++++++
>  block.h     |    2 ++
>  migration.c |    5 +++++
>  qerror.c    |    4 ++++
>  qerror.h    |    3 +++
>  5 files changed, 27 insertions(+)
>
> --
> 1.7.9.5

Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>