On 04.02.25 23:48, Alistair Popple wrote:

Currently DAX folio/page reference counts are managed differently to normal
pages. To allow these to be managed the same as normal pages introduce
vmf_insert_folio_pmd. This will map the entire PMD-sized folio and take
references as it would for a normally mapped page.

This is distinct from the current mechanism, vmf_insert_pfn_pmd, which
simply inserts a special devmap PMD entry into the page table without
holding a reference to the page for the mapping.

It is not currently useful to implement a more generic vmf_insert_folio()
which selects the correct behaviour based on folio_order(). This is because
PTE faults require only a subpage of the folio to be PTE mapped rather than
the entire folio. It would be possible to add this context somewhere but
callers already need to handle PTE faults and PMD faults separately so a
more generic function is not useful.

Signed-off-by: Alistair Popple <apopple@nvidia.com>

Nit: patch subject ;)

---

Changes for v7:

  - Fix bad pgtable handling for PPC64 (Thanks Dan and Dave)

Is it? ;) insert_pfn_pmd() still doesn't consume a "pgtable_t *"

But maybe I am missing something ...

-- 
Cheers,

David / dhildenb