Re: [PATCH v6 02/13] iomap: comment on atomic write checks in iomap_dio_bio_iter()

[Christoph Hellwig]

On Thu, Mar 13, 2025 at 05:12:59PM +0000, John Garry wrote:
>  		if (iter->flags & IOMAP_ATOMIC_HW) {
> +			/*
> +			* Ensure that the mapping covers the full write length,
> +			* otherwise we will submit multiple BIOs, which is
> +			* disallowed.
> +			*/

"disallowed" doesn't really explain anything, why is it disallowed?

Maybe:

			* Ensure that the mapping covers the full write length,
			* otherwise it can't be submitted as a single bio,
			* which is required to use hardware atomics.