This tool attempts to read all logical sectors of a block device, overwriting any sector that cannot be read due to an I/O error with zeros. It is intended to restore Linux dm-integrity volumes with invalid (corrupted) integrity tags.
If you wish to scrub a volume, consider creating a backup of the underlying physical device first.
Then run the tool with the volume device path (/dev/mapper/… or /dev/dm-…) as its single command‐line argument.
The block device is first read in large chunks (the maximum sectors per request as reported by the BLKSECTGET ioctl).
If a read results in an I/O error (EIO), the logical sectors in the chunk are read individually and any sector that
results in an I/O error is overwritten with zeros.
This tool might delete all your data and summon a seal. Use it at your own risk. The seal will demand fish.
If you are not using a filesystem with copy‐on‐write semantics or data journalling, you should probably rely on dm-integrity’s data journal.