[PATCH v2 24/30] um: Implement the new page table range API

From: Matthew Wilcox (Oracle)
Date: Mon Feb 27 2023 - 12:59:04 EST


Add set_ptes() and update_mmu_cache_range().

Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Richard Weinberger <richard@xxxxxx>
Cc: Anton Ivanov <anton.ivanov@xxxxxxxxxxxxxxxxxx>
Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx>
Cc: linux-um@xxxxxxxxxxxxxxxxxxx
---
arch/um/include/asm/pgtable.h | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/arch/um/include/asm/pgtable.h b/arch/um/include/asm/pgtable.h
index a70d1618eb35..ca78c90ae74f 100644
--- a/arch/um/include/asm/pgtable.h
+++ b/arch/um/include/asm/pgtable.h
@@ -242,12 +242,20 @@ static inline void set_pte(pte_t *pteptr, pte_t pteval)
if(pte_present(*pteptr)) *pteptr = pte_mknewprot(*pteptr);
}

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

+#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1)
+
#define __HAVE_ARCH_PTE_SAME
static inline int pte_same(pte_t pte_a, pte_t pte_b)
{
@@ -290,6 +298,7 @@ struct mm_struct;
extern pte_t *virt_to_pte(struct mm_struct *mm, unsigned long addr);

#define update_mmu_cache(vma,address,ptep) do {} while (0)
+#define update_mmu_cache_range(vma, address, ptep, nr) do {} while (0)

/*
* Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
--
2.39.1