[PATCH v7 5/9] arm64: hugetlb: Handle swap entries in huge_pte_offset() for contiguous hugepages

[Catalin Marinas]

On Tue, Aug 22, 2017 at 11:42:45AM +0100, Punit Agrawal wrote:
> diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
> index 594232598cac..b95e24dc3477 100644
> --- a/arch/arm64/mm/hugetlbpage.c
> +++ b/arch/arm64/mm/hugetlbpage.c
> @@ -214,6 +214,7 @@ pte_t *huge_pte_offset(struct mm_struct *mm,
>  	pgd_t *pgd;
>  	pud_t *pud;
>  	pmd_t *pmd;
> +	pte_t *pte;
>  
>  	pgd = pgd_offset(mm, addr);
>  	pr_debug("%s: addr:0x%lx pgd:%p\n", __func__, addr, pgd);
> @@ -221,19 +222,29 @@ pte_t *huge_pte_offset(struct mm_struct *mm,
>  		return NULL;
>  
>  	pud = pud_offset(pgd, addr);
> -	if (pud_none(*pud))
> +	if (sz != PUD_SIZE && pud_none(*pud))
>  		return NULL;
> -	/* swap or huge page */
> -	if (!pud_present(*pud) || pud_huge(*pud))
> +	/* hugepage or swap? */
> +	if (pud_huge(*pud) || !pud_present(*pud))
>  		return (pte_t *)pud;
>  	/* table; check the next level */
>  
> +	if (sz == CONT_PMD_SIZE)
> +		addr &= CONT_PMD_MASK;
> +
>  	pmd = pmd_offset(pud, addr);
> -	if (pmd_none(*pmd))
> +	if (!(sz == PMD_SIZE || sz == CONT_PMD_SIZE) &&
> +	    pmd_none(*pmd))
>  		return NULL;
> -	if (!pmd_present(*pmd) || pmd_huge(*pmd))
> +	if (pmd_huge(*pmd) || !pmd_present(*pmd))
>  		return (pte_t *)pmd;
>  
> +	if (sz == CONT_PTE_SIZE) {
> +		pte = pte_offset_kernel(
> +			pmd, (addr & CONT_PTE_MASK));
> +		return pte;
> +	}
> +
>  	return NULL;
>  }

I merged the patch almost as is (with the pte variable but
pte_offset_kernel() arguments on the same line); the pte variable is a
minor personal preference, so I'm not going to argue either way ;)).

Anyway, I pulled the whole series for 4.14, though I'll run some tests
over the next day or so.

Thanks.

-- 
Catalin