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Date: Wed, 6 Aug 2025 16:56:21 +0200
From: Christoph Hellwig <hch@lst.de>
To: Keith Busch <kbusch@meta.com>
Cc: linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, hch@lst.de,
	axboe@kernel.dk, Keith Busch <kbusch@kernel.org>
Subject: Re: [PATCH 1/2] block: accumulate segment page gaps per bio
Message-ID: <20250806145621.GC20102@lst.de>
References: <20250805195608.2379107-1-kbusch@meta.com>
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> index 0a29b20939d17..d0ed28d40fe02 100644
> --- a/include/linux/blk_types.h
> +++ b/include/linux/blk_types.h
> @@ -264,6 +264,8 @@ struct bio {
>  
>  	unsigned short		bi_max_vecs;	/* max bvl_vecs we can hold */
>  
> +	unsigned int		page_gaps;	/* a mask of all the vector gaps */

Bloating the bio for the gaps, especially as the bio is otherwise not
built to hardware limits at all seems like an odd tradeoff.