[PATCH -next v6 2/6] mm: page_table_check: move pxx_user_accessible_page into x86

From: Tong Tiangen
Date: Tue Apr 26 2022 - 03:52:47 EST


From: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>

The pxx_user_accessible_page() checks the PTE bit, it's
architecture-specific code, move them into x86's pgtable.h.

These helpers are being moved out to make the page table check framework
platform independent.

Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
Signed-off-by: Tong Tiangen <tongtiangen@xxxxxxxxxx>
Acked-by: Pasha Tatashin <pasha.tatashin@xxxxxxxxxx>
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
arch/x86/include/asm/pgtable.h | 17 +++++++++++++++++
mm/page_table_check.c | 17 -----------------
2 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 0821f87d495f..46fa65d818bd 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -1447,6 +1447,23 @@ static inline bool arch_faults_on_old_pte(void)
return false;
}

+#ifdef CONFIG_PAGE_TABLE_CHECK
+static inline bool pte_user_accessible_page(pte_t pte)
+{
+ return (pte_val(pte) & _PAGE_PRESENT) && (pte_val(pte) & _PAGE_USER);
+}
+
+static inline bool pmd_user_accessible_page(pmd_t pmd)
+{
+ return pmd_leaf(pmd) && (pmd_val(pmd) & _PAGE_PRESENT) && (pmd_val(pmd) & _PAGE_USER);
+}
+
+static inline bool pud_user_accessible_page(pud_t pud)
+{
+ return pud_leaf(pud) && (pud_val(pud) & _PAGE_PRESENT) && (pud_val(pud) & _PAGE_USER);
+}
+#endif
+
#endif /* __ASSEMBLY__ */

#endif /* _ASM_X86_PGTABLE_H */
diff --git a/mm/page_table_check.c b/mm/page_table_check.c
index eb0d0b71cdf6..3692bea2ea2c 100644
--- a/mm/page_table_check.c
+++ b/mm/page_table_check.c
@@ -52,23 +52,6 @@ static struct page_table_check *get_page_table_check(struct page_ext *page_ext)
return (void *)(page_ext) + page_table_check_ops.offset;
}

-static inline bool pte_user_accessible_page(pte_t pte)
-{
- return (pte_val(pte) & _PAGE_PRESENT) && (pte_val(pte) & _PAGE_USER);
-}
-
-static inline bool pmd_user_accessible_page(pmd_t pmd)
-{
- return pmd_leaf(pmd) && (pmd_val(pmd) & _PAGE_PRESENT) &&
- (pmd_val(pmd) & _PAGE_USER);
-}
-
-static inline bool pud_user_accessible_page(pud_t pud)
-{
- return pud_leaf(pud) && (pud_val(pud) & _PAGE_PRESENT) &&
- (pud_val(pud) & _PAGE_USER);
-}
-
/*
* An enty is removed from the page table, decrement the counters for that page
* verify that it is of correct type and counters do not become negative.
--
2.25.1