SCSI passthrough bypasses the block layer and issues SCSI commands
directly to the disk.  This breaks write notifiers and dirty bitmaps,
so that scsi-block devices cannot act as a mirror or backup source
(and commit too, even though that shouldn't be possible at all in the
lack of a backing file).  This series adds op blockers for that purpose.

There is currently a blk_op_unblock but no blk_op_block, so patch 2
adds it.

Paolo

Paolo Bonzini (2):
  scsi: add unrealize method for SCSI devices
  scsi: add block job opblockers for scsi-block

 block/block-backend.c          |  9 ++++++
 hw/scsi/scsi-bus.c             |  4 +++
 hw/scsi/scsi-disk.c            | 62 ++++++++++++++++++++++++++++++++++++++++++
 include/hw/scsi/scsi.h         |  1 +
 include/sysemu/block-backend.h |  1 +
 5 files changed, 77 insertions(+)

-- 
2.14.3