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Date: Mon, 9 Nov 2015 16:51:16 +0800
From: Gonglei <arei.gonglei@huawei.com>
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Subject: Re: [Qemu-devel] [PATCH v2] virtio-blk: trivial code optimization
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To: Paolo Bonzini <pbonzini@redhat.com>, qemu-devel@nongnu.org
Cc: stefanha@redhat.com, qemu-block@nongnu.org

On 2015/11/9 16:41, Paolo Bonzini wrote:
> 
> 
> On 09/11/2015 04:19, arei.gonglei@huawei.com wrote:
>> +             * 1. requests are not sequential
>> +             * 2. merge would exceed maximum number of IOVs
>> +             * 3. merge would exceed maximum transfer length of backend device
>> +             */
>> +            if (sector_num + nb_sectors != req->sector_num ||
>> +                niov > IOV_MAX - req->qiov.niov ||
>> +                req->qiov.size / BDRV_SECTOR_SIZE + nb_sectors > max_xfer_len) {
> 
> Hi Gonglei,
> 
> the third condition should also be changed to "new > max - old".
> 
Okay, will do.  :)

Thanks,
-Gonglei