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Date: Thu, 18 Dec 2025 10:45:26 +0100
From: Christoph Hellwig <hch@lst.de>
To: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	Carlos Maiolino <cem@kernel.org>,
	Damien Le Moal <dlemoal@kernel.org>,
	Hans Holmberg <hans.holmberg@wdc.com>, linux-block@vger.kernel.org,
	linux-xfs@vger.kernel.org
Subject: Re: [PATCH 1/3] block: add a bio_reuse helper
Message-ID: <20251218094526.GA10629@lst.de>
References: <20251218063234.1539374-1-hch@lst.de> <20251218063234.1539374-2-hch@lst.de> <aUPL8Jr39N-SIf_W@fedora>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Thu, Dec 18, 2025 at 05:40:00PM +0800, Ming Lei wrote:
> > +/**
> > + * bio_reuse - reuse a bio with the payload left intact
> > + * @bio bio to reuse
> > + *
> > + * Allow reusing an existing bio for another operation with all set up
> > + * fields including the payload, device and end_io handler left intact.
> > + *
> > + * Typically used for bios first used to read data which is then written
> > + * to another location without modification.
> > + */
> > +void bio_reuse(struct bio *bio)
> > +{
> > +	unsigned short vcnt = bio->bi_vcnt, i;
> > +	bio_end_io_t *end_io = bio->bi_end_io;
> > +	void *private = bio->bi_private;
> 
> The incoming bio can't be a cloned bio, so

It better no be, yes.