[$] XFS online filesystem scrubbing and repair

In a filesystem track session at the 2018 Linux Storage, Filesystem, andMemory-Management Summit (LSFMM), Darrick Wong talked about the onlinescrubbing and repair features he has been working on. His target has mostly beenXFS, but he has concurrently been working on scrubbing for ext4.Part of what he wanted to discuss was the possibility of standardizing someof these interfaces across different filesystem types.