From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Date: Fri, 19 Jul 2013 09:15:54 +0000 (+0200)
Subject: s390/pgtable: add pgste_get helper
X-Git-Tag: next-20130822~110^2~6
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=47247d56661f0e3a5c91865ec3e1c6814fa7dac4;p=karo-tx-linux.git

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>
---

diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index c2ec83566679..9ff99931f9aa 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
@@ -1102,7 +1111,7 @@ 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);