Re: [Qemu-devel] Block job commands in QEMU 1.2 [v2, including support for replication]

[Stefan Hajnoczi]

On Thu, May 24, 2012 at 03:41:29PM +0200, Paolo Bonzini wrote:
> changes from v1:
> - added per-job iostatus
> - added description of persistent dirty bitmap
> 
> The same content is also at
> http://wiki.qemu.org/Features/LiveBlockMigration/1.2
> 
> 
> QMP changes for error handling
> ==============================
> 
> * query-block-jobs: BlockJobInfo gets two new fields, paused and
> io-status.  The job-specific iostatus is completely separate from the
> block device iostatus.
> 
> 
> * block-stream: I would still like to add on_error to the existing
> block-stream command, if only to ease unit testing.  Concerns about the
> stability of the API can be handled by adding introspection (exporting
> the schema), which is not hard to do.  The new option is an enum with
> the following possible values:
> 
> 'report': The behavior is the same as in 1.1.  An I/O error will
> complete the job immediately with an error code.
> 
> 'ignore': An I/O error, respectively during a read or a write, will be
> ignored.  For streaming, the job will complete with an error and the
> backing file will be left in place.  For mirroring, the sector will be
> marked again as dirty and re-examined later.
> 
> 'stop': The job will be paused, and the job iostatus (which can be
> examined with query-block-jobs) is updated.
> 
> 'enospc': Behaves as 'stop' for ENOSPC errors, 'report' for others.

'stop' and 'enospc' must raise a QMP event so the user is notified when
the job is paused.  Are the details on this missing from this draft?

Stefan