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Date: Thu, 09 Apr 2009 14:30:37 +0100
From: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
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Subject: Re: [Qemu-devel] buffer alignment for block backends
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To: "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>

Anthony Liguori wrote:

> Stefano Stabellini wrote:
>> Anthony Liguori wrote:
>>
>>   
>>>> If you do not want to do that, another possible solution is to create a
>>>> new function called "qemu_blockalign" that would be implemented as
>>>> qemu_memalign(512, size);
>>>>       
>>> This is fine, but this is purely an optimization, it cannot be relied 
>>> upon in the general case.
>>>
>>>     
>>
>>
>> If you are OK with this, a simple patch like the following is
>> acceptable, or do you prefer a more formal approach involving a new
>> function in the BlockDriver interface?
>>   
> 
> Yes, but that's not covering very many of the cases.  There are still 
> places where we allocate bounce buffers that aren't with memalign (like 
> in block-qcow2.c).  Also, please document what the new function does and 
> when it should be used.
> 

Ok, I'll try to find all those places.