v4: Switch to new fleecing scheme, more native for Qemu's block-layer,
    see new patches 10-12 for details.

01,02: add Hanna's r-b
03: add const, add forgotten bdrv_release_dirty_bitmap()
04: rewrite bitmap parameter parsing
05: add Hanna's r-b
06: tiny wording fixes
07: new
08: fix comments, improve interface of new functions
09: fix grammar, add Hanna's and Nikita's r-bs
10-12: new fleecing scheme
tests: updated to use new fleecing scheme

===

These series brings several improvements to fleecing scheme:

1. support bitmap in copy-before-write filter

2. introduce snapshot-access API and filter, to make a new fleecing
   scheme. See "block: copy-before-write: realize snapshot-access API"
   commit message for details.

3. support "push backup with fleecing" scheme, when backup job is a
   client of common fleecing scheme. That helps when writes to final
   backup target are slow and we don't want guest writes hang waiting
   for copy-before-write operations to final target.

Vladimir Sementsov-Ogievskiy (18):
  block/block-copy: move copy_bitmap initialization to
    block_copy_state_new()
  block/dirty-bitmap: bdrv_merge_dirty_bitmap(): add return value
  block/block-copy: block_copy_state_new(): add bitmap parameter
  block/copy-before-write: add bitmap open parameter
  block/block-copy: add block_copy_reset()
  block: intoduce reqlist
  block/reqlist: reqlist_find_conflict(): use ranges_overlap()
  block/dirty-bitmap: introduce bdrv_dirty_bitmap_status()
  block/reqlist: add reqlist_wait_all()
  block/io: introduce block driver snapshot-access API
  block: introduce snapshot-access filter
  block: copy-before-write: realize snapshot-access API
  iotests/image-fleecing: add test-case for fleecing format node
  iotests.py: add qemu_io_pipe_and_status()
  iotests/image-fleecing: add test case with bitmap
  block: blk_root(): return non-const pointer
  qapi: backup: add immutable-source parameter
  iotests/image-fleecing: test push backup with fleecing

 qapi/block-core.json                        |  25 +-
 include/block/block-copy.h                  |   2 +
 include/block/block_int.h                   |  28 +++
 include/block/dirty-bitmap.h                |   4 +-
 include/block/reqlist.h                     |  75 ++++++
 include/qemu/hbitmap.h                      |  12 +
 include/sysemu/block-backend.h              |   2 +-
 block/backup.c                              |  61 ++++-
 block/block-backend.c                       |   2 +-
 block/block-copy.c                          | 150 +++++------
 block/copy-before-write.c                   | 265 +++++++++++++++++++-
 block/dirty-bitmap.c                        |  15 +-
 block/io.c                                  |  69 +++++
 block/monitor/bitmap-qmp-cmds.c             |   5 +-
 block/replication.c                         |   2 +-
 block/reqlist.c                             |  85 +++++++
 block/snapshot-access.c                     | 132 ++++++++++
 blockdev.c                                  |   1 +
 util/hbitmap.c                              |  33 +++
 MAINTAINERS                                 |   5 +-
 block/meson.build                           |   2 +
 tests/qemu-iotests/iotests.py               |   4 +
 tests/qemu-iotests/tests/image-fleecing     | 175 ++++++++++---
 tests/qemu-iotests/tests/image-fleecing.out | 223 +++++++++++++++-
 24 files changed, 1227 insertions(+), 150 deletions(-)
 create mode 100644 include/block/reqlist.h
 create mode 100644 block/reqlist.c
 create mode 100644 block/snapshot-access.c

-- 
2.31.1