From mboxrd@z Thu Jan  1 00:00:00 1970
From: Asias He <asias.hejun@gmail.com>
Subject: Re: [PATCH 1/2] kvm tools: Bring VIRTIO_BLK_F_SEG_MAX feature back
 to virtio blk
Date: Fri, 13 May 2011 22:34:44 +0800
Message-ID: <4DCD4184.3040803@gmail.com>
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Cc: Pekka Enberg <penberg@cs.helsinki.fi>,
	Cyrill Gorcunov <gorcunov@gmail.com>,
	Ingo Molnar <mingo@elte.hu>,
	Prasad Joshi <prasadjoshi124@gmail.com>, kvm@vger.kernel.org
To: Sasha Levin <levinsasha928@gmail.com>
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On 05/13/2011 10:07 PM, Sasha Levin wrote:
> On Fri, 2011-05-13 at 15:46 +0300, Pekka Enberg wrote:
>> On 5/13/11 5:40 AM, Asias He wrote:
>>> commit b764422bb0b46b00b896f6d4538ac3d3dde9e56b
>>> (kvm tools: Add support for multiple virtio-blk)
>>> removed the VIRTIO_BLK_F_SEG_MAX publishment to guest.
>>>
>>> There is no reason we should not support it. Just bring it back.
>>>
>>> Signed-off-by: Asias He<asias.hejun@gmail.com>
>>
>> Sasha?
> 
> I'm not sure why it was removed, must have missed it when updating
> struct blk_dev.
> 
> On the other hand, why do we need to limit max segment size?

That's because the number of entries in a scatter-gather operation must
be less than the entries in the virt queue we can offer.


-- 
Best Regards,
Asias He