[v2,0/8] qemu-img: rebase: add compression support

Message

Andrey Drobyshev Sept. 15, 2023, 4:20 p.m. UTC

v1 --> v2:
 * Choose proper BlockBackend when aligning buf_old;
 * Add new patch ("qemu-img: add chunk size parameter to
   compare_buffers()");
 * Rework write alignment logic; now writes are aligned to either
   subcluster or cluster size, depending on whether compressionis enabled;
 * Add new patch ("iotests/{024, 271}: add testcases for qemu-img
   rebase");
 * Add another compressed rebase testcase for images having subclusters.

v1: https://lists.nongnu.org/archive/html/qemu-block/2023-06/msg00068.html

NOTE: compressed rebase testcase for subclusters assume "compressed"
field in "qemu-img map" output.  This series is currently in the block
branch and is likely to be merged into master soon:

https://lists.nongnu.org/archive/html/qemu-devel/2023-09/msg01489.html


Andrey Drobyshev (8):
  qemu-img: rebase: stop when reaching EOF of old backing file
  qemu-iotests: 024: add rebasing test case for overlay_size >
    backing_size
  qemu-img: rebase: use backing files' BlockBackend for buffer alignment
  qemu-img: add chunk size parameter to compare_buffers()
  qemu-img: rebase: avoid unnecessary COW operations
  iotests/{024, 271}: add testcases for qemu-img rebase
  qemu-img: add compression option to rebase subcommand
  iotests: add tests for "qemu-img rebase" with compression

 docs/tools/qemu-img.rst    |   6 +-
 qemu-img-cmds.hx           |   4 +-
 qemu-img.c                 | 136 +++++++++++++++++++++++-------
 tests/qemu-iotests/024     | 117 ++++++++++++++++++++++++++
 tests/qemu-iotests/024.out |  73 ++++++++++++++++
 tests/qemu-iotests/271     | 131 +++++++++++++++++++++++++++++
 tests/qemu-iotests/271.out |  82 ++++++++++++++++++
 tests/qemu-iotests/314     | 165 +++++++++++++++++++++++++++++++++++++
 tests/qemu-iotests/314.out |  75 +++++++++++++++++
 9 files changed, 753 insertions(+), 36 deletions(-)
 create mode 100755 tests/qemu-iotests/314
 create mode 100644 tests/qemu-iotests/314.out