This series introduces a bottom intermediate node that eliminates the
dependency on the base that may change while stream job is running.
It happens when stream/commit parallel jobs are running on the same
backing chain. The base node of the stream job may be a top node of
the parallel commit job and can change before the stream job is
completed. We avoid that dependency by introducing the bottom node.

v2:
The function bdrv_find_overlay() with the same functionality has been
used in the qmp_block_stream() to find a bottom node.
The algorithm in the bdrv_do_is_allocated_above() was simplified.
The commit messages were modified.

Discussed in the e-mail threads with the message IDs
<1553866154-257311-1-git-send-email-andrey.shinkevich@virtuozzo.com>
<1550762799-830661-1-git-send-email-andrey.shinkevich@virtuozzo.com>

Andrey Shinkevich (2):
  block: include base when checking image chain for block allocation
  block/stream: introduce a bottom node

Vladimir Sementsov-Ogievskiy (1):
  block/stream: refactor stream_run: drop goto

 block/io.c                | 32 ++++++++++++++++++----
 block/stream.c            | 67 ++++++++++++++++++++++-------------------------
 block/trace-events        |  2 +-
 blockdev.c                |  7 ++++-
 include/block/block.h     |  5 +++-
 include/block/block_int.h |  6 ++---
 tests/qemu-iotests/245    |  4 +--
 7 files changed, 74 insertions(+), 49 deletions(-)

-- 
1.8.3.1