Re: [PATCH v3 05/11] mm, fsdax: Refactor memory-failure handler for dax mapping

Ruan Shiyang
2021-02-17T02:57:04Z

On 2021/2/10 下午9:33, Christoph Hellwig wrote:
>> +extern int mf_dax_mapping_kill_procs(struct address_space *mapping, pgoff_t index, int flags);
>
> No nee for the extern, please avoid the overly long line.

OK.

I'd like to confirm one thing... I have checked all of this patchset by
checkpatch.pl and it did not report the overly long line warning. So, I
should still obey the rule of 80 chars one line?

>
>> @@ -120,6 +121,13 @@ static int hwpoison_filter_dev(struct page *p)
>> if (PageSlab(p))
>> return -EINVAL;
>>
>> + if (pfn_valid(page_to_pfn(p))) {
>> + if (is_device_fsdax_page(p))
>> + return 0;
>> + else
>> + return -EINVAL;
>> + }
>> +
>
> This looks odd. For one there is no need for an else after a return.
> But more importantly page_mapping() as called below pretty much assumes
> a valid PFN, so something is fishy in this function.

Yes, a mistake here. I'll fix it.

>
>> + if (is_zone_device_page(p)) {
>> + if (is_device_fsdax_page(p))
>> + tk->addr = vma->vm_start +
>> + ((pgoff - vma->vm_pgoff) << PAGE_SHIFT);
>
> The arithmetics here scream for a common helper, I suspect there might
> be other places that could use the same helper.
>
>> +int mf_dax_mapping_kill_procs(struct address_space *mapping, pgoff_t index, int flags)
>
> Overly long line. Also the naming scheme with the mf_ seems rather
> unusual. Maybe dax_kill_mapping_procs? Also please add a kerneldoc
> comment describing the function given that it exported.
>

OK. Thanks for your guidance.

--
Thanks,
Ruan Shiyang.

>