Re: [PATCH v4 3/6] mm/vmalloc: Extract vmap_set_ptes() to consolidate PTE mapping logic

From: Uladzislau Rezki

Date: Fri Jun 26 2026 - 12:34:48 EST


On Thu, Jun 18, 2026 at 04:47:23PM +0800, Wen Jiang wrote:
> Extract the common PTE mapping logic from vmap_pte_range() into a
> shared helper vmap_set_ptes(). This handles both CONT_PTE and regular
> PTE mappings in a single function, preparing for the next patch which
> will extend vmap_pages_pte_range() to also use this helper.
>
> The #ifdef CONFIG_HUGETLB_PAGE guard is moved inside vmap_set_ptes(),
> so callers no longer need to handle the conditional compilation.
>
> No functional change.
>
> Signed-off-by: Wen Jiang <jiangwen6@xxxxxxxxxx>
> Tested-by: Xueyuan Chen <xueyuan.chen21@xxxxxxxxx>
> ---
> mm/vmalloc.c | 44 +++++++++++++++++++++++++++++++-------------
> 1 file changed, 31 insertions(+), 13 deletions(-)
>
> diff --git a/mm/vmalloc.c b/mm/vmalloc.c
> index 2c2f74a07f396..6660f240d27c9 100644
> --- a/mm/vmalloc.c
> +++ b/mm/vmalloc.c
> @@ -91,6 +91,35 @@ struct vfree_deferred {
> static DEFINE_PER_CPU(struct vfree_deferred, vfree_deferred);
>
> /*** Page table manipulation functions ***/
> +
> +/*
> + * Set PTE mappings for the given PFN. Try CONT_PTE mappings first when
> + * supported, otherwise fall back to PAGE_SIZE mappings.
> + *
> + * Return: mapping size.
> + */
> +static __always_inline unsigned long vmap_set_ptes(pte_t *pte,
> + unsigned long addr, unsigned long end, u64 pfn,
> + pgprot_t prot, unsigned int max_page_shift)
> +{
> +#ifdef CONFIG_HUGETLB_PAGE
> + if (max_page_shift > PAGE_SHIFT) {
> + unsigned long size;
> +
> + size = arch_vmap_pte_range_map_size(addr, end, pfn, max_page_shift);
> + if (size != PAGE_SIZE) {
> + pte_t entry = pfn_pte(pfn, prot);
> +
> + entry = arch_make_huge_pte(entry, ilog2(size), 0);
> + set_huge_pte_at(&init_mm, addr, pte, entry, size);
> + return size;
> + }
> + }
> +#endif
> + set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
> + return PAGE_SIZE;
> +}
> +
> static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
> phys_addr_t phys_addr, pgprot_t prot,
> unsigned int max_page_shift, pgtbl_mod_mask *mask)
> @@ -119,19 +148,8 @@ static int vmap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
> BUG();
> }
>
> -#ifdef CONFIG_HUGETLB_PAGE
> - size = arch_vmap_pte_range_map_size(addr, end, pfn, max_page_shift);
> - if (size != PAGE_SIZE) {
> - pte_t entry = pfn_pte(pfn, prot);
> -
> - entry = arch_make_huge_pte(entry, ilog2(size), 0);
> - set_huge_pte_at(&init_mm, addr, pte, entry, size);
> - pfn += PFN_DOWN(size);
> - continue;
> - }
> -#endif
> - set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
> - pfn++;
> + size = vmap_set_ptes(pte, addr, end, pfn, prot, max_page_shift);
> + pfn += PFN_DOWN(size);
> } while (pte += PFN_DOWN(size), addr += size, addr != end);
>
> lazy_mmu_mode_disable();
> --
> 2.34.1
>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>

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Uladzislau Rezki