Re: [PATCH v14 062/138] mm/migrate: Add folio_migrate_copy()

[Vlastimil Babka]

On 8/13/21 6:16 AM, Matthew Wilcox wrote:
> On Thu, Aug 12, 2021 at 01:56:24PM +0200, Vlastimil Babka wrote:
>> On 7/15/21 5:35 AM, Matthew Wilcox (Oracle) wrote:
>> > This is the folio equivalent of migrate_page_copy(), which is retained
>> > as a wrapper for filesystems which are not yet converted to folios.
>> > Also convert copy_huge_page() to folio_copy().
>> > 
>> > Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
>> 
>> Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
>> 
>> The way folio_copy() avoids cond_resched() for single page would IMHO deserve a
>> comment though, so it's not buried only in this thread.
> 
> I think folio_copy() deserves kernel-doc.
> 
> /**
>  * folio_copy - Copy the contents of one folio to another.
>  * @dst: Folio to copy to.
>  * @src: Folio to copy from.
>  *
>  * The bytes in the folio represented by @src are copied to @dst.
>  * Assumes the caller has validated that @dst is at least as large as @src.
>  * Can be called in atomic context for order-0 folios, but if the folio is
>  * larger, it may sleep.
>  */
> 
LGTM.