# Re: \[PATCH\] block: add a bi\_error field to struct bio

- From: Jens Axboe \<axboe@kernel.dk\>
- Date: 2015-07-24 16:36:49 
- List: linux-raid
- Page: https://ratatoskr.run/linux-raid/2015/07/4542589
- Thread: https://ratatoskr.run/linux-raid/2015/07/4538817/t.md

```text
On 07/24/2015 04:49 AM, Christoph Hellwig wrote:
> On Wed, Jul 22, 2015 at 03:59:46PM -0600, Jens Axboe wrote:
>> One possible solution would be to shrink bi_flags to an unsigned int, no
>> problems fitting that in. Then we could stuff bi_error in that (new) hole,
>> and we would end up having the same size again.
>
> As long as we use set/test/clear_bt on bi_flags that won't work unfortunately.

Right, I don't think we need to do that though. If you look at the flags usage, it's all over the map. Some use test/set_bit, some set it just by OR'ing the mask. There's no reason we can't make this work without relying on set/test_bit, and then shrink it to an unsigned int.

-- 
Jens Axboe

```