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Subject: Re: [PATCH v9] bio: limit bio max size
To:     Bart Van Assche <bvanassche@acm.org>,
        Changheun Lee <nanich.lee@samsung.com>, yi.zhang@redhat.com,
        ming.lei@redhat.com, bgoncalv@redhat.com, hch@lst.de,
        jaegeuk@kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org, patchwork-bot@kernel.org
References: <CGME20210503101008epcas1p25d6b727dafcf9ff24db6aa41a3f611fa@epcas1p2.samsung.com>
 <20210503095203.29076-1-nanich.lee@samsung.com>
 <72a0b4e7-a374-97fb-ae73-ed24f719da98@acm.org>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <c48d45cc-9c4f-0b6c-51d0-3044e7cdf7f5@kernel.dk>
Date:   Mon, 3 May 2021 08:59:41 -0600
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On 5/3/21 8:54 AM, Bart Van Assche wrote:
> On 5/3/21 2:52 AM, Changheun Lee wrote:
>>  struct queue_limits {
>> +	unsigned int		bio_max_bytes;
>> +
>>  	enum blk_bounce		bounce;
>>  	unsigned long		seg_boundary_mask;
>>  	unsigned long		virt_boundary_mask;
> 
> On April 23 Damien Le Moal posted the following comment about the
> bio_max_bytes member: "Please move this below in the structure together
> with all other fields that are unsigned int too." Making that change
> sounds like a good idea to me.

Why? It's next to an enum, so the patch (as it stands) actually fills a
hole in the struct. Moving it would be a mistake and waste more space.

If anything, we should move the bounce member below virt_boundary_mask,
but since this one fills a hole, that's better left as a separate patch.

-- 
Jens Axboe