Subject: [PATCH v11 04/11] Revert "mm/page_table_check: remove unused parameter in [__]page_table_check_pud_clear"

From: Rohan McLure <[email-masked]>
Date: Thu, 28 Mar 2024 15:55:24 +1100

This reverts commit 931c38e16499a057e30a3033f4d6a9c242f0f156.

Reinstate previously unused parameters for the purpose of supporting
powerpc platforms, as many do not encode user/kernel ownership of the
page in the pte, but instead in the address of the access.

Signed-off-by: Rohan McLure <[email-masked]>
---
 arch/x86/include/asm/pgtable.h   |  2 +-
 include/linux/page_table_check.h | 11 +++++++----
 include/linux/pgtable.h          |  2 +-
 mm/page_table_check.c            |  5 +++--
 4 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 82bbe115a1a4..e35b2b4f5ea1 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -1356,7 +1356,7 @@ static inline pud_t pudp_huge_get_and_clear(struct mm_struct *mm,
 {
 	pud_t pud = native_pudp_get_and_clear(pudp);
 
-	page_table_check_pud_clear(mm, pud);
+	page_table_check_pud_clear(mm, addr, pud);
 
 	return pud;
 }
diff --git a/include/linux/page_table_check.h b/include/linux/page_table_check.h
index 9243c920ed02..d01a00ffc1f9 100644
--- a/include/linux/page_table_check.h
+++ b/include/linux/page_table_check.h
@@ -16,7 +16,8 @@ extern struct page_ext_operations page_table_check_ops;
 void __page_table_check_zero(struct page *page, unsigned int order);
 void __page_table_check_pte_clear(struct mm_struct *mm, pte_t pte);
 void __page_table_check_pmd_clear(struct mm_struct *mm, pmd_t pmd);
-void __page_table_check_pud_clear(struct mm_struct *mm, pud_t pud);
+void __page_table_check_pud_clear(struct mm_struct *mm, unsigned long addr,
+				  pud_t pud);
 void __page_table_check_ptes_set(struct mm_struct *mm, unsigned long addr,
 				 pte_t *ptep, pte_t pte, unsigned int nr);
 void __page_table_check_pmd_set(struct mm_struct *mm, unsigned long addr,
@@ -59,12 +60,13 @@ static inline void page_table_check_pmd_clear(struct mm_struct *mm, pmd_t pmd)
 	__page_table_check_pmd_clear(mm, pmd);
 }
 
-static inline void page_table_check_pud_clear(struct mm_struct *mm, pud_t pud)
+static inline void page_table_check_pud_clear(struct mm_struct *mm,
+					      unsigned long addr, pud_t pud)
 {
 	if (static_branch_likely(&page_table_check_disabled))
 		return;
 
-	__page_table_check_pud_clear(mm, pud);
+	__page_table_check_pud_clear(mm, addr, pud);
 }
 
 static inline void page_table_check_ptes_set(struct mm_struct *mm,
@@ -125,7 +127,8 @@ static inline void page_table_check_pmd_clear(struct mm_struct *mm, pmd_t pmd)
 {
 }
 
-static inline void page_table_check_pud_clear(struct mm_struct *mm, pud_t pud)
+static inline void page_table_check_pud_clear(struct mm_struct *mm,
+					      unsigned long addr, pud_t pud)
 {
 }
 
diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index b2b4c1160d4a..6a5c44c2208e 100644
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -570,7 +570,7 @@ static inline pud_t pudp_huge_get_and_clear(struct mm_struct *mm,
 	pud_t pud = *pudp;
 
 	pud_clear(pudp);
-	page_table_check_pud_clear(mm, pud);
+	page_table_check_pud_clear(mm, address, pud);
 
 	return pud;
 }
diff --git a/mm/page_table_check.c b/mm/page_table_check.c
index 3a338fee6d00..a8c8fd7f06f8 100644
--- a/mm/page_table_check.c
+++ b/mm/page_table_check.c
@@ -171,7 +171,8 @@ void __page_table_check_pmd_clear(struct mm_struct *mm, pmd_t pmd)
 }
 EXPORT_SYMBOL(__page_table_check_pmd_clear);
 
-void __page_table_check_pud_clear(struct mm_struct *mm, pud_t pud)
+void __page_table_check_pud_clear(struct mm_struct *mm, unsigned long addr,
+				  pud_t pud)
 {
 	if (&init_mm == mm)
 		return;
@@ -217,7 +218,7 @@ void __page_table_check_pud_set(struct mm_struct *mm, unsigned long addr,
 	if (&init_mm == mm)
 		return;
 
-	__page_table_check_pud_clear(mm, *pudp);
+	__page_table_check_pud_clear(mm, addr, *pudp);
 	if (pud_user_accessible_page(pud)) {
 		page_table_check_set(pud_pfn(pud), PUD_SIZE >> PAGE_SHIFT,
 				     pud_write(pud));
-- 
2.44.0