Merge remote-tracking branch 'remotes/stefanha/tags/block-pull-request' into staging

Pull request

v2:
 * Fixed incorrect virtio_blk_data_plane_create() local_err refactoring in
   "hw/block: Use errp directly rather than local_err" that broke virtio-blk
   over virtio-mmio [Peter]

# gpg: Signature made Tue 19 Dec 2017 15:08:14 GMT
# gpg:                using RSA key 0x9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request: (23 commits)
  qemu-iotests: add 203 savevm with IOThreads test
  iothread: fix iothread_stop() race condition
  iotests: add VM.add_object()
  blockdev: add x-blockdev-set-iothread force boolean
  docs: mark nested AioContext locking as a legacy API
  block: avoid recursive AioContext acquire in bdrv_inactivate_all()
  virtio-blk: reject configs with logical block size > physical block size
  virtio-blk: make queue size configurable
  qemu-iotests: add 202 external snapshots IOThread test
  blockdev: add x-blockdev-set-iothread testing command
  iothread: add iothread_by_id() API
  block: drop unused BlockDirtyBitmapState->aio_context field
  block: don't keep AioContext acquired after internal_snapshot_prepare()
  block: don't keep AioContext acquired after blockdev_backup_prepare()
  block: don't keep AioContext acquired after drive_backup_prepare()
  block: don't keep AioContext acquired after external_snapshot_prepare()
  blockdev: hold AioContext for bdrv_unref() in external_snapshot_clean()
  qdev: drop unused #include "sysemu/iothread.h"
  dev-storage: Fix the unusual function name
  hw/block: Use errp directly rather than local_err
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

# Conflicts:
#	hw/core/qdev-properties-system.c