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	id 7818F68BFE; Fri,  1 Nov 2024 06:47:59 +0100 (CET)
Date: Fri, 1 Nov 2024 06:47:59 +0100
From: Christoph Hellwig <hch@lst.de>
To: Damien Le Moal <dlemoal@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
	Chris Mason <clm@fb.com>, Josef Bacik <josef@toxicpanda.com>,
	David Sterba <dsterba@suse.com>,
	Damien Le Moal <damien.lemoal@wdc.com>, linux-block@vger.kernel.org,
	linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 1/4] block: fix bio_split_rw_at to take
 zone_write_granularity into account
Message-ID: <20241101054759.GA13514@lst.de>
References: <20241101052206.437530-1-hch@lst.de> <20241101052206.437530-2-hch@lst.de> <a7b87e01-045e-423e-854d-4707f9102c75@kernel.org>
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On Fri, Nov 01, 2024 at 02:34:31PM +0900, Damien Le Moal wrote:
> > -	bytes = ALIGN_DOWN(bytes, lim->logical_block_size);
> > +	bytes = ALIGN_DOWN(bytes, lim->zone_write_granularity ?
> > +			lim->zone_write_granularity : lim->logical_block_size);
> 
> Nit: we could also do:
> 
> 	bytes = ALIGN_DOWN(bytes,
> 		max(lim->logical_block_size, lim->zone_write_granularity));

That's what I had first.  It is a little odd as zone_write_granularity
is defined to be >= logical_block_size, though.

> Also, I wonder if we should leave read split as is based on the logical block
> size only ? Probably does not matter much...

Good point.  Probably doesn't matter much, but randomly forcing it on
reads seems odd.