Re: [RFC 0/3] Btrfs checksum offload

[Kanchan Joshi <joshi.k@samsung.com>]

On 1/29/2025 8:25 PM, Johannes Thumshirn wrote:
> For instance if we get a checksum error on btrfs we not only report in
> in dmesg, but also try to repair the affected sector if we do have a
> data profile with redundancy.
> 
> So while this patchset offloads the submission side work of the checksum
> tree to the PI code, I don't see the back-propagation of the errors into
> btrfs and the triggering of the repair code.
> 
> I get it's a RFC, but as it is now it essentially breaks functionality
> we rely on. Can you add this part as well so we can evaluate the
> patchset not only from the write but also from the read side.

I tested the series for read, but only the success cases. In this case 
checksum generation/verification happens only within the device. It was 
slightly tricky to inject an error and I skipped that.

Since separate checksum I/Os are omitted, this is about handling the 
error condition in data read I/O path itself. I have not yet checked if 
repair code triggers when Btrfs is working with existing 'nodatasum' 
mount option. But I get your point that this needs to be handled.