[PATCH 1/3] mm: define generic pudp_invalidate() implementation
David Hildenbrand (Arm)
david at kernel.org
Wed Sep 9 03:24:56 PDT 2026
On 9/9/26 11:00, Jinjiang Tu wrote:
> x86 and riscv have identical pudp_invalidate() implementations. Move it to
> mm/pgtable-generic.c with the __HAVE_ARCH_PUDP_INVALIDATE override guard.
> PowerPC keeps its own implementation. In the later patch, arm64 will use
> the generic implementation too.
>
> No functional change intended.
>
> Signed-off-by: Jinjiang Tu <tujinjiang at huawei.com>
> ---
> arch/powerpc/include/asm/book3s/64/pgtable.h | 1 +
> arch/riscv/include/asm/pgtable.h | 3 ---
> arch/riscv/mm/pgtable.c | 9 ---------
> arch/x86/include/asm/pgtable.h | 3 ---
> arch/x86/mm/pgtable.c | 12 ------------
> include/linux/pgtable.h | 7 +++++++
> mm/pgtable-generic.c | 14 ++++++++++++++
> 7 files changed, 22 insertions(+), 27 deletions(-)
>
> diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h
> index f4db7d7fbd5c..55d33c5537f1 100644
> --- a/arch/powerpc/include/asm/book3s/64/pgtable.h
> +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
> @@ -1419,6 +1419,7 @@ static inline pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm,
> #define __HAVE_ARCH_PMDP_INVALIDATE
> extern pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
> pmd_t *pmdp);
> +#define __HAVE_ARCH_PUDP_INVALIDATE
> extern pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address,
> pud_t *pudp);
>
> diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
> index 40b1ed4f3ea8..327fa378032b 100644
> --- a/arch/riscv/include/asm/pgtable.h
> +++ b/arch/riscv/include/asm/pgtable.h
> @@ -1159,9 +1159,6 @@ static inline pud_t pud_mkinvalid(pud_t pud)
> return __pud(pud_val(pud) & ~(_PAGE_PRESENT | _PAGE_PROT_NONE));
> }
>
> -extern pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address,
> - pud_t *pudp);
> -
> static inline pud_t pud_modify(pud_t pud, pgprot_t newprot)
> {
> return pte_pud(pte_modify(pud_pte(pud), newprot));
> diff --git a/arch/riscv/mm/pgtable.c b/arch/riscv/mm/pgtable.c
> index 9c4427d0b187..156e385e7db4 100644
> --- a/arch/riscv/mm/pgtable.c
> +++ b/arch/riscv/mm/pgtable.c
> @@ -154,15 +154,6 @@ pmd_t pmdp_collapse_flush(struct vm_area_struct *vma,
> return pmd;
> }
>
> -pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address,
> - pud_t *pudp)
> -{
> - VM_WARN_ON_ONCE(!pud_present(*pudp));
> - pud_t old = pudp_establish(vma, address, pudp, pud_mkinvalid(*pudp));
> -
> - flush_pud_tlb_range(vma, address, address + HPAGE_PUD_SIZE);
> - return old;
> -}
> #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
>
> pte_t pte_mkwrite(pte_t pte, struct vm_area_struct *vma)
> diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
> index d5f4917c1edc..97051c02385e 100644
> --- a/arch/x86/include/asm/pgtable.h
> +++ b/arch/x86/include/asm/pgtable.h
> @@ -1387,9 +1387,6 @@ static inline pud_t pudp_establish(struct vm_area_struct *vma,
> extern pmd_t pmdp_invalidate_ad(struct vm_area_struct *vma,
> unsigned long address, pmd_t *pmdp);
>
> -pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address,
> - pud_t *pudp);
> -
> /*
> * Page table pages are page-aligned. The lower half of the top
> * level is used for userspace and the top half for the kernel.
> diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
> index cb03f5a2b243..0945908631dc 100644
> --- a/arch/x86/mm/pgtable.c
> +++ b/arch/x86/mm/pgtable.c
> @@ -519,18 +519,6 @@ pmd_t pmdp_invalidate_ad(struct vm_area_struct *vma, unsigned long address,
> }
> #endif
>
> -#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && \
> - defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
> -pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address,
> - pud_t *pudp)
> -{
> - VM_WARN_ON_ONCE(!pud_present(*pudp));
> - pud_t old = pudp_establish(vma, address, pudp, pud_mkinvalid(*pudp));
> - flush_pud_tlb_range(vma, address, address + HPAGE_PUD_SIZE);
> - return old;
> -}
> -#endif
> -
> /**
> * reserve_top_address - Reserve a hole in the top of the kernel address space
> * @reserve: Size of hole to reserve
> diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
> index 8c093c119e5a..32173005b087 100644
> --- a/include/linux/pgtable.h
> +++ b/include/linux/pgtable.h
> @@ -1318,6 +1318,13 @@ extern pmd_t pmdp_invalidate_ad(struct vm_area_struct *vma,
> unsigned long address, pmd_t *pmdp);
> #endif
>
> +#ifndef __HAVE_ARCH_PUDP_INVALIDATE
> +#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
> +extern pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address,
> + pud_t *pudp);
No "extern" please.
Staring at this file, I do wonder why we are not smarter about combining blocks. E.g., here simply:
diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index e3c8ab96941c5..8c9fe3bf580d4 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -1229,9 +1229,9 @@ static inline void pmdp_set_wrprotect(struct mm_struct *mm,
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
#endif
-#ifndef __HAVE_ARCH_PUDP_SET_WRPROTECT
-#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
+#ifndef __HAVE_ARCH_PUDP_SET_WRPROTECT
static inline void pudp_set_wrprotect(struct mm_struct *mm,
unsigned long address, pud_t *pudp)
{
@@ -1245,9 +1245,13 @@ static inline void pudp_set_wrprotect(struct mm_struct *mm,
{
BUILD_BUG();
}
-#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
-#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
#endif
+#ifndef __HAVE_ARCH_PUDP_INVALIDATE
+pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address,
+ pud_t *pudp);
+#endif
+#endif /* CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD */
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
> +#endif
> +#endif
> +
> #ifndef __HAVE_ARCH_PTE_SAME
> static inline int pte_same(pte_t pte_a, pte_t pte_b)
> {
> diff --git a/mm/pgtable-generic.c b/mm/pgtable-generic.c
> index b91b1a98029c..ac1175d9a59a 100644
> --- a/mm/pgtable-generic.c
> +++ b/mm/pgtable-generic.c
> @@ -217,6 +217,20 @@ pmd_t pmdp_invalidate_ad(struct vm_area_struct *vma, unsigned long address,
> }
> #endif
>
> +#ifndef __HAVE_ARCH_PUDP_INVALIDATE
> +#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
I'd revert these and similarly see if they can be combined somehow (likely combining with
pudp_huge_clear_flush is harder as we are quite inconsistent with it, gluing it to
__HAVE_ARCH_PMDP_HUGE_CLEAR_FLUSH).
Which raises the question whether we could also piggy-back on __HAVE_ARCH_PMDP_SET_WRPROTECT
(I suspect no without a closer look.)
--
Cheers,
David
More information about the linux-arm-kernel
mailing list