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Date: Tue, 29 Jul 2014 15:33:40 +0800
From: Zhang Zhen <zhenzhang.zhang@huawei.com>
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Subject: Re: [PATCH v2] ubifs: refactor ubifs_file_mmap()
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On 2014/7/29 15:20, Artem Bityutskiy wrote:
> On Tue, 2014-07-29 at 11:50 +0800, Zhang Zhen wrote:
>> On 2014/7/29 0:25, Artem Bityutskiy wrote:
>>> On Tue, 2014-07-22 at 14:28 +0800, Zhang Zhen wrote:
>>>> generic_file_mmap() set vma->vm_ops = &generic_file_vm_ops,
>>>> then ubifs_file_mmap set vma->vm_ops = &ubifs_file_vm_ops.
>>>> So it is redundant.
>>>> And there is no kind of file does not supply page reading function
>>>> in ubifs. The readpage() check up for mmap file in generic_file_mmap()
>>>> is not needed.
>>>>
>>>> So remove the call of generic_file_mmap().
>>>>
>>>> Change v1 -> v2:
>>>> - deleted the mapping variable
>>>> Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
>>>
>>> Hi, I am not sure about this patch. 'generic_file_mmap()' covers !
>>> CONFIG_MMU case too, for example.
>>>
>> Yes, I missed that. We can add #ifdef CONFIG_MMU in ubifs_file_mmap().
>> Considering the patch itself is not important changes, we can give up
>> this patch, remain the same.
>>
>> What do you think?
> 
> I think it is better to leave it as it is, because that's not too bad
> and works. Changing this has a risk of breaking something. UBIFS does
> not enjoy a huge user base like, say, ext4, so the breakage could easily
> go unnoticed for long time.
> 
OK.