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Subject: Re: [RFC v3 PATCH 3/5] mm: refactor do_munmap() to extract the common
 part
To:     Michal Hocko <mhocko@kernel.org>
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        akpm@linux-foundation.org, peterz@infradead.org, mingo@redhat.com,
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        linux-kernel@vger.kernel.org
References: <1530311985-31251-1-git-send-email-yang.shi@linux.alibaba.com>
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 <20180702134226.GX19043@dhcp22.suse.cz>
From:   Yang Shi <yang.shi@linux.alibaba.com>
Message-ID: <5aa8953d-3781-8b22-89f6-994a52ea0172@linux.alibaba.com>
Date:   Mon, 2 Jul 2018 09:59:06 -0700
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On 7/2/18 6:42 AM, Michal Hocko wrote:
> On Sat 30-06-18 06:39:43, Yang Shi wrote:
>> Introduces two new helper functions:
>>    * munmap_addr_sanity()
>>    * munmap_lookup_vma()
>>
>> They will be used by do_munmap() and the new do_munmap with zapping
>> large mapping early in the later patch.
>>
>> There is no functional change, just code refactor.
> There are whitespace changes which make the code much harder to review
> than necessary.
>> +static inline bool munmap_addr_sanity(unsigned long start, size_t len)
>>   {
>> -	unsigned long end;
>> -	struct vm_area_struct *vma, *prev, *last;
>> +	if ((offset_in_page(start)) || start > TASK_SIZE || len > TASK_SIZE - start)
>> +		return false;
>>   
>> -	if ((offset_in_page(start)) || start > TASK_SIZE || len > TASK_SIZE-start)
>> -		return -EINVAL;
> e.g. here.

Oh, yes. I did some coding style cleanup too.