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Date: Fri, 23 May 2025 07:48:54 -0600
From: Keith Busch <kbusch@kernel.org>
To: Christoph Hellwig <hch@infradead.org>
Cc: Keith Busch <kbusch@meta.com>, linux-block@vger.kernel.org,
	linux-nvme@lists.infradead.org
Subject: Re: [PATCH 2/5] block: add support for copy offload
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In-Reply-To: <aDB6Hdp9ZQ1gX5gr@infradead.org>

On Fri, May 23, 2025 at 06:37:33AM -0700, Christoph Hellwig wrote:
> On Fri, May 23, 2025 at 07:26:45AM -0600, Keith Busch wrote:
> > Darn, this part of the proposal is really the core concept of this patch
> > set that everything builds around. It's what allows submitting
> > arbitrarily large sized copy requests and letting the block layer
> > efficiently split a bio to the queue limits later.
> 
> Well, you can still do that without overloading the bio_bvec by just
> making bi_io_vec in the bio itself a union.

I like that idea.
 
>  - bio_add_copy_src not updating bi_size is unexpected and annoying :)

Ha, I currently have the submitter responsible for bi_size. Your
suggestion will make this easier to use.