QA output created by 252
Format and mount
Create the original files
Compare files
ec8bb3b24d5b0f1b5bdf8c8f0f541ee6  SCRATCH_MNT/test-252/file2
CoW and unmount
write missed bytes expect 8388608 got 0
Compare files
3ed86318f4ff8da26c1c2a6e3041f9be  SCRATCH_MNT/test-252/file2
Check for damage
