[PATCH v4 19/45] powerpc/mm: Refactor pte_update() on book3s/32

From: Christophe Leroy
Date: Tue May 19 2020 - 01:49:19 EST


When CONFIG_PTE_64BIT is set, pte_update() operates on
'unsigned long long'
When CONFIG_PTE_64BIT is not set, pte_update() operates on
'unsigned long'

In asm/page.h, we have pte_basic_t which is 'unsigned long long'
when CONFIG_PTE_64BIT is set and 'unsigned long' otherwise.

Refactor pte_update() using pte_basic_t.

While we are at it, drop the comment on 44x which is not applicable
to book3s version of pte_update().

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
arch/powerpc/include/asm/book3s/32/pgtable.h | 58 +++++++-------------
1 file changed, 20 insertions(+), 38 deletions(-)

diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h
index 0d4bccb4b9f2..d2fc324cdf07 100644
--- a/arch/powerpc/include/asm/book3s/32/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/32/pgtable.h
@@ -253,53 +253,35 @@ extern void flush_hash_entry(struct mm_struct *mm, pte_t *ptep,
* and the PTE may be either 32 or 64 bit wide. In the later case,
* when using atomic updates, only the low part of the PTE is
* accessed atomically.
- *
- * In addition, on 44x, we also maintain a global flag indicating
- * that an executable user mapping was modified, which is needed
- * to properly flush the virtually tagged instruction cache of
- * those implementations.
*/
-#ifndef CONFIG_PTE_64BIT
-static inline unsigned long pte_update(pte_t *p,
- unsigned long clr,
- unsigned long set)
+static inline pte_basic_t pte_update(pte_t *p, unsigned long clr, unsigned long set)
{
- unsigned long old, tmp;
-
- __asm__ __volatile__("\
-1: lwarx %0,0,%3\n\
- andc %1,%0,%4\n\
- or %1,%1,%5\n"
-" stwcx. %1,0,%3\n\
- bne- 1b"
- : "=&r" (old), "=&r" (tmp), "=m" (*p)
- : "r" (p), "r" (clr), "r" (set), "m" (*p)
- : "cc" );
-
- return old;
-}
-#else /* CONFIG_PTE_64BIT */
-static inline unsigned long long pte_update(pte_t *p,
- unsigned long clr,
- unsigned long set)
-{
- unsigned long long old;
+ pte_basic_t old;
unsigned long tmp;

- __asm__ __volatile__("\
-1: lwarx %L0,0,%4\n\
- lwzx %0,0,%3\n\
- andc %1,%L0,%5\n\
- or %1,%1,%6\n"
-" stwcx. %1,0,%4\n\
- bne- 1b"
+ __asm__ __volatile__(
+#ifndef CONFIG_PTE_64BIT
+"1: lwarx %0, 0, %3\n"
+" andc %1, %0, %4\n"
+#else
+"1: lwarx %L0, 0, %3\n"
+" lwz %0, -4(%3)\n"
+" andc %1, %L0, %4\n"
+#endif
+" or %1, %1, %5\n"
+" stwcx. %1, 0, %3\n"
+" bne- 1b"
: "=&r" (old), "=&r" (tmp), "=m" (*p)
- : "r" (p), "r" ((unsigned long)(p) + 4), "r" (clr), "r" (set), "m" (*p)
+#ifndef CONFIG_PTE_64BIT
+ : "r" (p),
+#else
+ : "b" ((unsigned long)(p) + 4),
+#endif
+ "r" (clr), "r" (set), "m" (*p)
: "cc" );

return old;
}
-#endif /* CONFIG_PTE_64BIT */

/*
* 2.6 calls this without flushing the TLB entry; this is wrong
--
2.25.0