On 8/8/25 14:11, Pankaj Raghav (Samsung) wrote:

From: Pankaj Raghav <redacted>

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 <redacted>
Signed-off-by: David Hildenbrand <redacted>
Signed-off-by: Pankaj Raghav <redacted>
---
  include/linux/huge_mm.h | 22 ++++++++++++++++++++++
  1 file changed, 22 insertions(+)

Reviewed-by: Hannes Reinecke <hare@suse.de>

Cheers,

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