The other four drivers that support backing files (qcow, qcow2,
parallels, vmdk) all rely on the block layer to populate zeroes when
reading beyond EOF of a short backing file. We can simplify the qed
code by doing likewise.
Signed-off-by: Eric Blake <address@hidden>
---
I noticed this during my audit that v1 of Vladimir's series was correct.
No change in iotests results (test 274 is currently failing for qed,
but for other reasons:
+Traceback (most recent call last):
+ File "274", line 24, in <module>
+ iotests.verify_image_format(supported_fmts=['qcow2'])
+AttributeError: module 'iotests' has no attribute 'verify_image_format'
)