[PATCH v2 25/30] x86: Implement the new page table range API

From: Matthew Wilcox (Oracle)
Date: Mon Feb 27 2023 - 12:58:44 EST


Convert set_pte_at() into set_ptes() and add a noop
update_mmu_cache_range().

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: x86@xxxxxxxxxx
Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
---
arch/x86/include/asm/pgtable.h | 21 +++++++++++++++++----
1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 84be3e07b112..f424371ea143 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -1019,13 +1019,22 @@ static inline pud_t native_local_pudp_get_and_clear(pud_t *pudp)
return res;
}

-static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
- pte_t *ptep, pte_t pte)
+static inline void set_ptes(struct mm_struct *mm, unsigned long addr,
+ pte_t *ptep, pte_t pte, unsigned int nr)
{
- page_table_check_ptes_set(mm, addr, ptep, pte, 1);
- set_pte(ptep, pte);
+ page_table_check_ptes_set(mm, addr, ptep, pte, nr);
+
+ for (;;) {
+ set_pte(ptep, pte);
+ if (--nr == 0)
+ break;
+ ptep++;
+ pte = __pte(pte_val(pte) + PAGE_SIZE);
+ }
}

+#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1)
+
static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
pmd_t *pmdp, pmd_t pmd)
{
@@ -1291,6 +1300,10 @@ static inline void update_mmu_cache(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep)
{
}
+static inline void update_mmu_cache_range(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep, unsigned int nr)
+{
+}
static inline void update_mmu_cache_pmd(struct vm_area_struct *vma,
unsigned long addr, pmd_t *pmd)
{
--
2.39.1