Comment by StillBored

Which is just lame, its mostly because the block layer doesn't support file based fencing. A mistake made a decade an a half ago, and no one has the will/political power to fix it.

If the block layer supported it, solving the problem of fencing an ATA device would be as simple as issuing a whole device flush instead of a SYNC_CACHE with range. Which for soft raid devices would make a huge impact because only the devices with dirty data need to be flushed.

Of course the excuse today, is that most scsi devices can't do range based sync either, and just fall back to whole device because no one uses the command. Chicken/egg.