Re: [PATCH RFC 4/4] md/raid0: Atomic write support

[Christoph Hellwig]

On Tue, Sep 03, 2024 at 03:07:48PM +0000, John Garry wrote:
>  	if (sectors < bio_sectors(bio)) {
> -		struct bio *split = bio_split(bio, sectors, GFP_NOIO,
> +		struct bio *split;
> +
> +		if (bio->bi_opf & REQ_ATOMIC)
> +			return false;

I guess this is the erroring out when attempting to split the request.
Can you add a comment to explain that and why it can't happen for the
normal I/O patterns?