[PATCH v1 06/14] arm64/mm: ptep_clear_flush_young(): New layer to manage contig bit

[Ryan Roberts]

Create a new layer for the in-table PTE manipulation APIs. For now, The
existing API is prefixed with double underscore to become the
arch-private API and the public API is just a simple wrapper that calls
the private API.

The public API implementation will subsequently be used to transparently
manipulate the contiguous bit where appropriate. But since there are
already some contig-aware users (e.g. hugetlb, kernel mapper), we must
first ensure those users use the private API directly so that the future
contig-bit manipulations in the public API do not interfere with those
existing uses.

No behavioural changes intended.

Signed-off-by: Ryan Roberts <ryan.roberts at arm.com>
---
 arch/arm64/include/asm/pgtable.h | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 1f4efa17cc39..450428b11c49 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -137,7 +137,7 @@ static inline pteval_t __phys_to_pte_val(phys_addr_t phys)
  * so that we don't erroneously return false for pages that have been
  * remapped as PROT_NONE but are yet to be flushed from the TLB.
  * Note that we can't make any assumptions based on the state of the access
- * flag, since ptep_clear_flush_young() elides a DSB when invalidating the
+ * flag, since __ptep_clear_flush_young() elides a DSB when invalidating the
  * TLB.
  */
 #define pte_accessible(mm, pte)	\
@@ -904,8 +904,7 @@ static inline int __ptep_test_and_clear_young(struct vm_area_struct *vma,
 	return pte_young(pte);
 }
 
-#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
-static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
+static inline int __ptep_clear_flush_young(struct vm_area_struct *vma,
 					 unsigned long address, pte_t *ptep)
 {
 	int young = __ptep_test_and_clear_young(vma, address, ptep);
@@ -1153,6 +1152,13 @@ static inline int ptep_test_and_clear_young(struct vm_area_struct *vma,
 	return __ptep_test_and_clear_young(vma, addr, ptep);
 }
 
+#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
+static inline int ptep_clear_flush_young(struct vm_area_struct *vma,
+				unsigned long addr, pte_t *ptep)
+{
+	return __ptep_clear_flush_young(vma, addr, ptep);
+}
+
 #endif /* !__ASSEMBLY__ */
 
 #endif /* __ASM_PGTABLE_H */
-- 
2.25.1