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Date: Fri, 23 Jan 2026 06:44:48 +0100
From: Christoph Hellwig <hch@lst.de>
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	Christian Brauner <brauner@kernel.org>,
	Carlos Maiolino <cem@kernel.org>, Qu Wenruo <wqu@suse.com>,
	Al Viro <viro@zeniv.linux.org.uk>, linux-block@vger.kernel.org,
	linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 03/14] iov_iter: extract a iov_iter_extract_bvecs
 helper from bio code
Message-ID: <20260123054448.GB24902@lst.de>
References: <20260119074425.4005867-1-hch@lst.de> <20260119074425.4005867-4-hch@lst.de> <20260122174703.GX5945@frogsfrogsfrogs>
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On Thu, Jan 22, 2026 at 09:47:03AM -0800, Darrick J. Wong wrote:
> > -	struct page **pages = (struct page **)bv;
> 
> Huh.  We type-abuse an array of bio_vec's as an array of struct page
> pointers??
> 
> As a straight hoist the patch looks correct but I'm confused about this.

Yes.  This uses the larger space allocated for bio_vecs to first
place the pages at the end, and then filling in the bio_vecs from the
beginning.  I think the comments describe it pretty well, but if you
have ideas for enhancement, this might be a good time to update them.