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Date: Thu, 7 Dec 2023 17:20:51 +0800
From: Ming Lei <ming.lei@redhat.com>
To: Kent Overstreet <kent.overstreet@linux.dev>
Cc: axboe@kernel.dk, linux-fsdevel@vger.kernel.org,
	linux-block@vger.kernel.org,
	Phillip Lougher <phillip@squashfs.org.uk>
Subject: Re: [PATCH 1/3] block: Rework bio_for_each_segment_all()
Message-ID: <ZXGOc8HnUV2Q58SE@fedora>
References: <20231122232818.178256-1-kent.overstreet@linux.dev>
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In-Reply-To: <20231122232818.178256-1-kent.overstreet@linux.dev>
X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.7

On Wed, Nov 22, 2023 at 06:28:13PM -0500, Kent Overstreet wrote:
> This patch reworks bio_for_each_segment_all() to be more inline with how
> the other bio iterators work:
> 
>  - bio_iter_all_peek() now returns a synthesized bio_vec; we don't stash
>    one in the iterator and pass a pointer to it - bad. This way makes it
>    clearer what's a constructed value vs. a reference to something
>    pre-existing, and it also will help with cleaning up and
>    consolidating code with bio_for_each_folio_all().
> 
>  - We now provide bio_for_each_segment_all_continue(), for squashfs:
>    this makes their code clearer.
> 
> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
> Cc: Jens Axboe <axboe@kernel.dk>
> Cc: linux-block@vger.kernel.org
> Cc: Ming Lei <ming.lei@redhat.com>
> Cc: Phillip Lougher <phillip@squashfs.org.uk>
> Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

The original way was just for avoiding tree-wide change and keep bvec
pointer, and peek & advance is more cleaner, for the block layer change:

Reviewed-by: Ming Lei <ming.lei@redhat.com>


thanks,
Ming