Re: [v5 01/15] mm/zone_device: support large zone device private folios

From: David Hildenbrand

Date: Thu Sep 11 2025 - 07:45:31 EST


On 08.09.25 02:04, Balbir Singh wrote:
Add routines to support allocation of large order zone device folios
and helper functions for zone device folios, to check if a folio is
device private and helpers for setting zone device data.

When large folios are used, the existing page_free() callback in
pgmap is called when the folio is freed, this is true for both
PAGE_SIZE and higher order pages.

Zone device private large folios do not support deferred split and
scan like normal THP folios.

Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: Zi Yan <ziy@xxxxxxxxxx>
Cc: Joshua Hahn <joshua.hahnjy@xxxxxxxxx>
Cc: Rakie Kim <rakie.kim@xxxxxx>
Cc: Byungchul Park <byungchul@xxxxxx>
Cc: Gregory Price <gourry@xxxxxxxxxx>
Cc: Ying Huang <ying.huang@xxxxxxxxxxxxxxxxx>
Cc: Alistair Popple <apopple@xxxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx>
Cc: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Cc: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
Cc: Nico Pache <npache@xxxxxxxxxx>
Cc: Ryan Roberts <ryan.roberts@xxxxxxx>
Cc: Dev Jain <dev.jain@xxxxxxx>
Cc: Barry Song <baohua@xxxxxxxxxx>
Cc: Lyude Paul <lyude@xxxxxxxxxx>
Cc: Danilo Krummrich <dakr@xxxxxxxxxx>
Cc: David Airlie <airlied@xxxxxxxxx>
Cc: Simona Vetter <simona@xxxxxxxx>
Cc: Ralph Campbell <rcampbell@xxxxxxxxxx>
Cc: Mika Penttilä <mpenttil@xxxxxxxxxx>
Cc: Matthew Brost <matthew.brost@xxxxxxxxx>
Cc: Francois Dugast <francois.dugast@xxxxxxxxx>

Signed-off-by: Balbir Singh <balbirs@xxxxxxxxxx>
---

You missed my comments of this patch in v3.

--
Cheers

David / dhildenb