[PATCH v1 01/11] arm/pgtable: define PFN_PTE_SHIFT on arm and arm64

David Hildenbrand david at redhat.com
Tue Jan 23 03:31:43 PST 2024


>>
>>> If high bits are used for
>>> something else, then we might produce a garbage PTE on overflow, but that
>>> shouldn't really matter I concluded for folio_pte_batch() purposes, we'd not
>>> detect "belongs to this folio batch" either way.
>>
>> Exactly.
>>
>>>
>>> Maybe it's likely cleaner to also have a custom pte_next_pfn() on ppc, I just
>>> hope that we don't lose any other arbitrary PTE bits by doing the pte_pgprot().
>>
>> I don't see the need for ppc to implement pte_next_pfn().
> 
> Agreed.

So likely we should then do on top for powerpc (whitespace damage):

diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index a04ae4449a025..549a440ed7f65 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -220,10 +220,7 @@ void set_ptes(struct mm_struct *mm, unsigned long addr, pte_t *ptep,
                         break;
                 ptep++;
                 addr += PAGE_SIZE;
-               /*
-                * increment the pfn.
-                */
-               pte = pfn_pte(pte_pfn(pte) + 1, pte_pgprot((pte)));
+               pte = pte_next_pfn(pte);
         }
  }
  


-- 
Cheers,

David / dhildenb




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