Re: [PATCH v2 4/5] mm: add largest_zero_folio() routine

[Hannes Reinecke]

On 8/8/25 14:11, Pankaj Raghav (Samsung) wrote:
> From: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
>
> The callers of mm_get_huge_zero_folio() have access to a mm struct and
> the lifetime of the huge_zero_folio is tied to the lifetime of the mm
> struct.
>
> largest_zero_folio() will give access to huge_zero_folio when
> PERSISTENT_HUGE_ZERO_FOLIO config option is enabled for callers that do not
> want to tie the lifetime to a mm struct. This is very useful for
> filesystem and block layers where the request completions can be async
> and there is no guarantee on the mm struct lifetime.
>
> This function will return a ZERO_PAGE folio if PERSISTENT_HUGE_ZERO_FOLIO
> is disabled or if we failed to allocate a huge_zero_folio during early
> init.
>
> Co-developed-by: David Hildenbrand <david@xxxxxxxxxx>
> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
> Signed-off-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
> ---
>   include/linux/huge_mm.h | 22 ++++++++++++++++++++++
>   1 file changed, 22 insertions(+)
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>

Cheers,

Hannes
--
Dr. Hannes Reinecke                  Kernel Storage Architect
hare@xxxxxxx                                +49 911 74053 688
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