Merge remote-tracking branch 'stefanha/block' into staging

Merge remote-tracking branch 'stefanha/block' into staging

# By Peter Lieven (5) and others
# Via Stefan Hajnoczi
* stefanha/block:
  block/raw: add .bdrv_get_info
  block: fix bdrv_read_unthrottled()
  cpus: Let vm_stop[_force_state]() always flush block devices
  block-migration: efficiently encode zero blocks
  block/raw: add bdrv_co_write_zeroes
  block: add bdrv_write_zeroes()
  block: fix vvfat error path for enable_write_target
  QEMUBH: make AioContext's bh re-entrant
  dataplane: sync virtio.c and vring.c virtqueue state
  gluster: Add discard support for GlusterFS block driver.
  gluster: Use pkg-config to configure GlusterFS block driver

Message-id: 1374223132-29107-1-git-send-email-stefanha@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>