[PATCH 2/5] mm/arm64: constify pte_get*() and contpte get logic

Pedro Falcato <[email protected]> Fri, 24 Jul 2026 11:20:14 +0100
Newsgroups org.kernel.vger.linux-parisc,org.infradead.lists.linux-arm-kernel,org.kernel.vger.linux-fsdevel,org.kernel.vger.linux-kernel,org.kvack.linux-mm,org.ozlabs.lists.linuxppc-dev
Message-ID <[email protected]>
None of the contpte code needs write access to the PTEs.

Signed-off-by: Pedro Falcato <[email protected]>
---
 arch/arm64/include/asm/pgtable.h | 10 +++++-----
 arch/arm64/mm/contpte.c          |  4 ++--
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index a2681d755358..043bc0649cee 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -378,7 +378,7 @@ static inline void __set_pte(pte_t *ptep, pte_t pte)
 	__set_pte_complete(pte);
 }
 
-static inline pte_t __ptep_get(pte_t *ptep)
+static inline pte_t __ptep_get(const pte_t *ptep)
 {
 	return READ_ONCE(*ptep);
 }
@@ -1652,8 +1652,8 @@ extern void __contpte_try_fold(struct mm_struct *mm, unsigned long addr,
 				pte_t *ptep, pte_t pte);
 extern void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
 				pte_t *ptep, pte_t pte);
-extern pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte);
-extern pte_t contpte_ptep_get_lockless(pte_t *orig_ptep);
+extern pte_t contpte_ptep_get(const pte_t *ptep, pte_t orig_pte);
+extern pte_t contpte_ptep_get_lockless(const pte_t *orig_ptep);
 extern void contpte_set_ptes(struct mm_struct *mm, unsigned long addr,
 				pte_t *ptep, pte_t pte, unsigned int nr);
 extern void contpte_clear_full_ptes(struct mm_struct *mm, unsigned long addr,
@@ -1732,7 +1732,7 @@ static inline unsigned int pte_batch_hint(pte_t *ptep, pte_t pte)
  */
 
 #define ptep_get ptep_get
-static inline pte_t ptep_get(pte_t *ptep)
+static inline pte_t ptep_get(const pte_t *ptep)
 {
 	pte_t pte = __ptep_get(ptep);
 
@@ -1743,7 +1743,7 @@ static inline pte_t ptep_get(pte_t *ptep)
 }
 
 #define ptep_get_lockless ptep_get_lockless
-static inline pte_t ptep_get_lockless(pte_t *ptep)
+static inline pte_t ptep_get_lockless(const pte_t *ptep)
 {
 	pte_t pte = __ptep_get(ptep);
 
diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c
index 2de12656b4d8..3853ecd2cee9 100644
--- a/arch/arm64/mm/contpte.c
+++ b/arch/arm64/mm/contpte.c
@@ -310,7 +310,7 @@ void __contpte_try_unfold(struct mm_struct *mm, unsigned long addr,
 }
 EXPORT_SYMBOL_GPL(__contpte_try_unfold);
 
-pte_t contpte_ptep_get(pte_t *ptep, pte_t orig_pte)
+pte_t contpte_ptep_get(const pte_t *ptep, pte_t orig_pte)
 {
 	/*
 	 * Gather access/dirty bits, which may be populated in any of the ptes
@@ -367,7 +367,7 @@ static inline bool contpte_is_consistent(pte_t pte, unsigned long pfn,
 			pgprot_val(prot) == pgprot_val(orig_prot);
 }
 
-pte_t contpte_ptep_get_lockless(pte_t *orig_ptep)
+pte_t contpte_ptep_get_lockless(const pte_t *orig_ptep)
 {
 	/*
 	 * The ptep_get_lockless() API requires us to read and return *orig_ptep
-- 
2.55.0