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Date: Mon, 14 May 2012 21:03:47 -0500
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] [PATCH 02/13] Implement cpu_physical_memory_zero()
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To: Benjamin Herrenschmidt <benh@kernel.crashing.org>, qemu-devel@nongnu.org, David Gibson <david@gibson.dropbear.id.au>

On 05/14/2012 08:23 PM, David Gibson wrote:
> On Mon, May 14, 2012 at 07:42:00PM -0500, Anthony Liguori wrote:
>> On 05/09/2012 11:48 PM, Benjamin Herrenschmidt wrote:
>>> From: David Gibson<david@gibson.dropbear.id.au>
> [snip]
>>> @@ -3581,6 +3581,59 @@ void cpu_physical_memory_rw(target_phys_addr_t addr, uint8_t *buf,
>>>       }
>>>   }
>>>
>>> +void cpu_physical_memory_zero(target_phys_addr_t addr, int len)
>>> +{
>>
>> I'd think a memset() like interface would be better but...
>
> I can work with that.
>
>> We should definitely implement this function in terms of
>> cpu_physical_memory_write instead of open coding the logic again.
>
> Hrm.  Having solved merge conflicts several times by recopying the
> cpu_physical_memory_rw() logic, I can certainly see the attraction in
> that.  However, the point of this function is *not* to have to
> allocate a temporary buffer, and I don't really see how to combine the
> logic without that.

Just use a fixed buffer (uint8_t buffer[512]) and call cpu_physical_memory_rw 
multiple times with an offset.

Regards,

Anthony Liguori

>