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Date: Thu, 15 Aug 2024 17:26:38 +0200
From: Christoph Hellwig <hch@lst.de>
To: John Garry <john.g.garry@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>, axboe@kernel.dk,
	martin.petersen@oracle.com, linux-block@vger.kernel.org,
	kbusch@kernel.org
Subject: Re: [PATCH 1/2] block: Read max write zeroes once for
 __blkdev_issue_write_zeroes()
Message-ID: <20240815152638.GA17618@lst.de>
References: <20240815082755.105242-1-john.g.garry@oracle.com> <20240815082755.105242-2-john.g.garry@oracle.com> <20240815124047.GA7803@lst.de> <3275afad-cb94-4c8e-b70f-3a7e8bacd89b@oracle.com>
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On Thu, Aug 15, 2024 at 02:29:46PM +0100, John Garry wrote:
> On 15/08/2024 13:40, Christoph Hellwig wrote:
>> On Thu, Aug 15, 2024 at 08:27:54AM +0000, John Garry wrote:
>>> +/*
>>> + * Pass bio_write_zeroes_limit() return value in @limit, as the return
>>> + * value may change after a REQ_OP_WRITE_ZEROES is issued.
>>> + */
>> I don't think that really helps all that much to explain the issue,
>> which is about SCSI not having an ahead of time flag that reliably
>> works for write same support, which makes it clear the limit to 0 on
>> the first I/O completion.  Maybe you can actually spell this out?
>
> Please just tell me what you would like to see, and I will copy verbatim.

Probably just what I just wrote.  Unless Martin can come up with
better language.