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Date: Tue, 11 Nov 2025 10:07:55 +0100
From: Christoph Hellwig <hch@lst.de>
To: Caleb Sander Mateos <csander@purestorage.com>
Cc: Jens Axboe <axboe@kernel.dk>, Damien Le Moal <dlemoal@kernel.org>,
	Christoph Hellwig <hch@lst.de>, linux-block@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] zloop: use blk_rq_nr_phys_segments() instead of
 iterating bvecs
Message-ID: <20251111090755.GA12545@lst.de>
References: <20251108230101.4187106-1-csander@purestorage.com> <20251108230101.4187106-3-csander@purestorage.com>
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On Sat, Nov 08, 2025 at 04:01:01PM -0700, Caleb Sander Mateos wrote:
> The number of bvecs can be obtained directly from struct request's
> nr_phys_segments field via blk_rq_nr_phys_segments(), so use that
> instead of iterating over the bvecs an extra time.

Same reason this doesn't work as Ming explained for ublk.

Maybe we should lift this code from loop/zloop into a well documented
common helper to make it more obvious?