The compression filter driver is introduced as suggested by Max. A sample usage of the filter can be found in the test #214. Now, multiple clusters can be written compressed. It is useful for the backup job.
v8: The filter child was changed from the 'backing' to the 'file' one. Discussed in the email thread with the message ID <1573670589-229357-1-git-send-email-andrey.shinkev...@virtuozzo.com> Andrey Shinkevich (3): block: introduce compress filter driver qcow2: Allow writing compressed data of multiple clusters tests/qemu-iotests: add case to write compressed data of multiple clusters block/Makefile.objs | 1 + block/filter-compress.c | 201 +++++++++++++++++++++++++++++++++++++++++++++ block/qcow2.c | 102 +++++++++++++++++------ qapi/block-core.json | 10 ++- tests/qemu-iotests/214 | 43 ++++++++++ tests/qemu-iotests/214.out | 14 ++++ 6 files changed, 340 insertions(+), 31 deletions(-) create mode 100644 block/filter-compress.c -- 1.8.3.1