Re: [PATCH v2 3/3] net: netcp: rework the code for get/set sw_data in dma desc
From: Murali Karicheri
Date: Mon Feb 22 2016 - 12:04:17 EST
On 02/19/2016 05:25 PM, Arnd Bergmann wrote:
> On Friday 19 February 2016 17:21:57 Murali Karicheri wrote:
>>>> get_pkt_info(&dma_buf, &tmp, &dma_desc, ndesc);
>>>> - get_sw_data((u32 *)&buf_ptr, &buf_len, ndesc);
>>>> + /* warning!!!! We are retrieving the virtual ptr in the sw_data
>>>> + * field as a 32bit value. Will not work on 64bit machines
>>>> + */
>>>> + buf_ptr = (void *)GET_SW_DATA0(ndesc);
>>>> + buf_len = (int)GET_SW_DATA1(desc);
>>>
>>> I would have abstracted the retrieval of a pointer again,
>>> and added the comment in the helper function once, it doesn't
>>> really need to be duplicated everywhere.
>>>
>> Arnd,
>>
>> I thought about it to add it to the API. API currently set buffer
>> and ptr. It would be an issue only if store/retrieve ptr in/from the sw_data.
>> So for the comment to be really useful to someone who is changing the code,
>> doesn't it make sense to add it at the point of invocation as done in this
>> patch? No?
>>
>
> Up to you, it was just an idea and you have my Ack either way.
>
> Arnd
>
Ok. Thanks
--
Murali Karicheri
Linux Kernel, Keystone