New convert introduced simpler chunk/extent allocation algorithm, at the
cost of complex backup superblock migration codes.
Use specially built ext2 images to test if btrfs-convert can convert and
rollback images without problem.
All these special ext2 image have blocks/holes across 2nd btrfs backup
superblock.
The naming of test image is like the following:
|<------superblock migration range----->|
64M 64M + 64K
|-Data--|-Data--|/Hole//|-Data--|/Hole//|-Data--|--Data--| = drdhdhdrd
These test cases should check all typical layouts and make sure new
convert works.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>