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 | 11 ++++++++---
2 files changed, 13 insertions(+), 8 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..3a5d6937fb51 100644
--- a/arch/arm64/mm/contpte.c
+++ b/arch/arm64/mm/contpte.c
@@ -26,6 +26,11 @@ static inline pte_t *contpte_align_down(pte_t *ptep)
return PTR_ALIGN_DOWN(ptep, sizeof(*ptep) * CONT_PTES);
}
+#define contpte_align_down(ptep)
\
+ _Generic((ptep),
\
+ const pte_t *: (const pte_t *) contpte_align_down((pte_t *)
(ptep)), \
+ pte_t *: contpte_align_down((pte_t *) ptep))
+
static inline pte_t *contpte_align_addr_ptep(unsigned long *start,
unsigned long *end, pte_t *ptep,
unsigned int nr)
@@ -310,7 +315,7 @@ 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 +372,7 @@ 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
@@ -386,10 +391,10 @@ pte_t contpte_ptep_get_lockless(pte_t *orig_ptep)
* because it is not part of a contpte range.
*/
+ const pte_t *ptep;
pgprot_t orig_prot;
unsigned long pfn;
pte_t orig_pte;
- pte_t *ptep;
pte_t pte;
int i;
--
2.55.0
