# Re: block: correctly fallback for zeroout

- From: Martin K. Petersen \<hidden\>
- Date: 2016-06-10 02:05:55 
- List: linux-block
- Page: https://ratatoskr.run/linux-block/2016/06/4770019
- Thread: https://ratatoskr.run/linux-block/2016/06/4770019/t.md

```text
>>>>> "Christoph" == Christoph Hellwig [ref] writes:

>> Userland apps rely on EOPNOTSUPP, we can't break that.

Christoph> Rely on what exactly?  Current we return EOPNOTSUPP if the
Christoph> device doesn't claim to support discards, but it returns 0 if
Christoph> the device first claims to support it but then fails the I/O.

Hopefully we can clean up this when/if we go the fallocate() route.

-- 
Martin K. Petersen	Oracle Linux Engineering
```