[PATCH v4 0/5] qcow2: Implement zstd cluster compression method

[Denis Plotnikov <dplotnikov@virtuozzo.com>]

v4:
   * the series is rebased on top of 01 "block/qcow2-threads: fix qcow2_decompress"
   * 01 is just a no-change resend to avoid extra dependencies. Still, it may be merged in separate

v3:
   * remove redundant max compression type value check [Vladimir, Eric]
     (the switch below checks everything)
   * prevent compression type changing on "qemu-img amend" [Vladimir]
   * remove zstd config setting, since it has been added already by
     "migration" patches [Vladimir]
   * change the compression type error message [Vladimir] 
   * fix alignment and 80-chars exceeding [Vladimir]

v2:
   * rework compression type setting [Vladimir]
   * squash iotest changes to the compression type introduction patch [Vladimir, Eric]
   * fix zstd availability checking in zstd iotest [Vladimir]
   * remove unnecessry casting [Eric]
   * remove rudundant checks [Eric]
   * fix compressed cluster layout in qcow2 spec [Vladimir]
   * fix wording [Eric, Vladimir]
   * fix compression type filtering in iotests [Eric]

v1:
   the initial series

---
zstd comression method is faster than the only available zlib.
The series adds zstd to the methods available for clusters compression.

The implementation is done with respect to the recently added compression
type additional header to the qcow2 specification.


Denis Plotnikov (4):
  qcow2: introduce compression type feature
  qcow2: rework the cluster compression routine
  qcow2: add zstd cluster compression
  iotests: 287: add qcow2 compression type test

Vladimir Sementsov-Ogievskiy (1):
  block/qcow2-threads: fix qcow2_decompress

 docs/interop/qcow2.txt           |  20 +++
 configure                        |   2 +-
 qapi/block-core.json             |  23 +++-
 block/qcow2.h                    |  18 ++-
 include/block/block_int.h        |   1 +
 block/qcow2-threads.c            | 206 ++++++++++++++++++++++++++++---
 block/qcow2.c                    | 108 ++++++++++++++++
 tests/qemu-iotests/031.out       |  14 +--
 tests/qemu-iotests/036.out       |   4 +-
 tests/qemu-iotests/049.out       | 102 +++++++--------
 tests/qemu-iotests/060.out       |   1 +
 tests/qemu-iotests/061.out       |  34 ++---
 tests/qemu-iotests/065           |  28 +++--
 tests/qemu-iotests/080           |   2 +-
 tests/qemu-iotests/144.out       |   4 +-
 tests/qemu-iotests/182.out       |   2 +-
 tests/qemu-iotests/242.out       |   5 +
 tests/qemu-iotests/255.out       |   8 +-
 tests/qemu-iotests/287           | 127 +++++++++++++++++++
 tests/qemu-iotests/287.out       |  43 +++++++
 tests/qemu-iotests/common.filter |   3 +-
 tests/qemu-iotests/group         |   1 +
 22 files changed, 643 insertions(+), 113 deletions(-)
 create mode 100755 tests/qemu-iotests/287
 create mode 100644 tests/qemu-iotests/287.out

-- 
2.17.0