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To:     Ming Lei <ming.lei@redhat.com>
Cc:     John Garry <john.g.garry@oracle.com>, axboe@kernel.dk,
        kbusch@kernel.org, hch@lst.de, sagi@grimberg.me,
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        Himanshu Madhani <himanshu.madhani@oracle.com>
Subject: Re: [PATCH v2 01/16] block: Add atomic write operations to
 request_queue limits
From:   "Martin K. Petersen" <martin.petersen@oracle.com>
Organization: Oracle Corporation
Message-ID: <yq1cyv9flkw.fsf@ca-mkp.ca.oracle.com>
References: <20231212110844.19698-1-john.g.garry@oracle.com>
        <20231212110844.19698-2-john.g.garry@oracle.com>
        <ZXkIEnQld577uHqu@fedora>
        <36ee54b4-b8d5-4b3c-81a0-cc824b6ef68e@oracle.com>
        <ZXmjdnIqGHILTfQN@fedora>
Date:   Wed, 13 Dec 2023 23:38:10 -0500
In-Reply-To: <ZXmjdnIqGHILTfQN@fedora> (Ming Lei's message of "Wed, 13 Dec
        2023 20:28:38 +0800")
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Ming,

> Relying on driver to provide sound value is absolutely bad design from
> API viewpoint.

All the other queue_limits are validated by the LLDs. It's challenging
to lift that validation to the block layer since the values reported are
heavily protocol-dependent and thus information is lost if we do it
somewhere else.

-- 
Martin K. Petersen	Oracle Linux Engineering