On 9/12/25 19:20, David Hildenbrand wrote: > On 12.09.25 06:49, Balbir Singh wrote: >> On 9/11/25 22:52, David Hildenbrand wrote: >>> On 11.09.25 14:49, Balbir Singh wrote: >>>> On 9/11/25 21:45, David Hildenbrand wrote: >>>>> 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 <[email protected]> >>>>>> Cc: David Hildenbrand <[email protected]> >>>>>> Cc: Zi Yan <[email protected]> >>>>>> Cc: Joshua Hahn <[email protected]> >>>>>> Cc: Rakie Kim <[email protected]> >>>>>> Cc: Byungchul Park <[email protected]> >>>>>> Cc: Gregory Price <[email protected]> >>>>>> Cc: Ying Huang <[email protected]> >>>>>> Cc: Alistair Popple <[email protected]> >>>>>> Cc: Oscar Salvador <[email protected]> >>>>>> Cc: Lorenzo Stoakes <[email protected]> >>>>>> Cc: Baolin Wang <[email protected]> >>>>>> Cc: "Liam R. Howlett" <[email protected]> >>>>>> Cc: Nico Pache <[email protected]> >>>>>> Cc: Ryan Roberts <[email protected]> >>>>>> Cc: Dev Jain <[email protected]> >>>>>> Cc: Barry Song <[email protected]> >>>>>> Cc: Lyude Paul <[email protected]> >>>>>> Cc: Danilo Krummrich <[email protected]> >>>>>> Cc: David Airlie <[email protected]> >>>>>> Cc: Simona Vetter <[email protected]> >>>>>> Cc: Ralph Campbell <[email protected]> >>>>>> Cc: Mika Penttilä <[email protected]> >>>>>> Cc: Matthew Brost <[email protected]> >>>>>> Cc: Francois Dugast <[email protected]> >>>>>> >>>>>> Signed-off-by: Balbir Singh <[email protected]> >>>>>> --- >>>>> >>>>> You missed my comments of this patch in v3. >>>>> >>>> >>>> Hi, David >>>> >>>> Looks I missed your comments, just checked those were largely about >>>> alignment and >>>> integrating the code for DEVICE_COHERENT and DEVICE_PRIVATE cases into >>>> similar looking >>>> bits for zone device folio free and code-alignment. I'll take a look and >>>> update as needed. >>> >>> Yes, and the confusing folio->mapping = NULL that I cannot connect to THP >>> support. >>> >> >> I can remove that, let me reunify those bits, seems relatively straight >> forward > > BTW, I was wondering when we invalidate folio_test_anon() by clearing > folio->mapping int he current code flow? > > I mean, this must happen at some point when freeing device folios. >
The free_zone_device_folio() code does that. Lines 434 onwards there is a comment that explains it Balbir
