On Tue 21 Apr 2020 10:11:14 AM CEST, Denis Plotnikov <dplotni...@virtuozzo.com> wrote: > The patch adds some preparation parts for incompatible compression type > feature to qcow2 allowing the use different compression methods for > image clusters (de)compressing. > > It is implied that the compression type is set on the image creation and > can be changed only later by image conversion, thus compression type > defines the only compression algorithm used for the image, and thus, > for all image clusters. > > The goal of the feature is to add support of other compression methods > to qcow2. For example, ZSTD which is more effective on compression than ZLIB. > > The default compression is ZLIB. Images created with ZLIB compression type > are backward compatible with older qemu versions. > > Adding of the compression type breaks a number of tests because now the > compression type is reported on image creation and there are some changes > in the qcow2 header in size and offsets. > > The tests are fixed in the following ways: > * filter out compression_type for many tests > * fix header size, feature table size and backing file offset > affected tests: 031, 036, 061, 080 > header_size +=8: 1 byte compression type > 7 bytes padding > feature_table += 48: incompatible feature compression type > backing_file_offset += 56 (8 + 48 -> header_change + > feature_table_change) > * add "compression type" for test output matching when it isn't filtered > affected tests: 049, 060, 061, 065, 144, 182, 242, 255 > > Signed-off-by: Denis Plotnikov <dplotni...@virtuozzo.com> > Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> > Reviewed-by: Eric Blake <ebl...@redhat.com> > QAPI part: > Acked-by: Markus Armbruster <arm...@redhat.com>
Reviewed-by: Alberto Garcia <be...@igalia.com> Berto