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Date: Tue, 4 Jun 2024 09:05:03 +0200
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Subject: Re: [PATCH v20 01/12] block: Introduce queue limits and sysfs for
 copy-offload support
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To: Christoph Hellwig <hch@lst.de>, Nitesh Shetty <nj.shetty@samsung.com>
Cc: Jens Axboe <axboe@kernel.dk>, Jonathan Corbet <corbet@lwn.net>,
 Alasdair Kergon <agk@redhat.com>, Mike Snitzer <snitzer@kernel.org>,
 Mikulas Patocka <mpatocka@redhat.com>, Keith Busch <kbusch@kernel.org>,
 Sagi Grimberg <sagi@grimberg.me>, Chaitanya Kulkarni <kch@nvidia.com>,
 Alexander Viro <viro@zeniv.linux.org.uk>,
 Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
 martin.petersen@oracle.com, bvanassche@acm.org, david@fromorbit.com,
 damien.lemoal@opensource.wdc.com, anuj20.g@samsung.com, joshi.k@samsung.com,
 nitheshshetty@gmail.com, gost.dev@samsung.com, linux-block@vger.kernel.org,
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 dm-devel@lists.linux.dev, linux-nvme@lists.infradead.org,
 linux-fsdevel@vger.kernel.org
References: <20240604043142.GB28886@lst.de>
From: Hannes Reinecke <hare@suse.de>
In-Reply-To: <20240604043142.GB28886@lst.de>
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On 6/4/24 06:31, Christoph Hellwig wrote:
> On Mon, Jun 03, 2024 at 06:43:56AM +0000, Nitesh Shetty wrote:
>>> Also most block limits are in kb.  Not that I really know why we are
>>> doing that, but is there a good reason to deviate from that scheme?
>>>
>> We followed discard as a reference, but we can move to kb, if that helps
>> with overall readability.
> 
> I'm not really sure what is better.  Does anyone remember why we did
> the _kb version?  Either way some amount of consistency would be nice.
> 
If memory serves correctly we introduced the _kb versions as a 
convenience to the user; exposing values in 512 bytes increments tended
to be confusing, especially when it comes to LBA values (is the size in 
units of hardware sector size? 512 increments? kilobytes?)

Cheers,

Hannes
-- 
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@suse.de                                +49 911 74053 688
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