s390/pgtable: add pgste_get helper

ptep_modify_prot_start uses the pgste_set helper to store the pgste,
while ptep_modify_prot_commit uses its own pointer magic to retrieve
the value again. Add the pgste_get help function to keep things
symmetrical and improve readability.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index b59b44badae9..26ee897aa1d6 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -619,6 +619,15 @@ static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste)
 #endif
 }
 
+static inline pgste_t pgste_get(pte_t *ptep)
+{
+        unsigned long pgste = 0;
+#ifdef CONFIG_PGSTE
+        pgste = *(unsigned long *)(ptep + PTRS_PER_PTE);
+#endif
+        return __pgste(pgste);
+}
+
 static inline void pgste_set(pte_t *ptep, pgste_t pgste)
 {
 #ifdef CONFIG_PGSTE
@@ -1098,7 +1107,7 @@ static inline void ptep_modify_prot_commit(struct mm_struct *mm,
         pgste_t pgste;
 
         if (mm_has_pgste(mm)) {
-                pgste = *(pgste_t *)(ptep + PTRS_PER_PTE);
+                pgste = pgste_get(ptep);
                 pgste_set_key(ptep, pgste, pte);
                 pgste_set_pte(ptep, pte);
                 pgste_set_unlock(ptep, pgste);