[PATCH 3.16 069/305] powerpc/mm/hash64: Factor out hash preload psize check

Ben Hutchings
2016-08-14T10:59:12Z

From: Michael Ellerman <mpe@ellerman.id.au>

commit 8bbc9b7b001eaab8abf7e9e24edf1bb285c8d825 upstream.

Currently we have a check in hash_preload() against the psize, which is
only included when CONFIG_PPC_MM_SLICES is enabled. We want to expand
this check in a subsequent patch, so factor it out to allow that. As a
bonus it removes the #ifdef in the C code.

Unfortunately we can't put this in the existing CONFIG_PPC_MM_SLICES
block because it would require a forward declaration.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
arch/powerpc/mm/hash_utils_64.c | 21 +++++++++++++++++----
1 file changed, 17 insertions(+), 4 deletions(-)

--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -1196,6 +1196,22 @@ bail:
}
EXPORT_SYMBOL_GPL(hash_page);

+#ifdef CONFIG_PPC_MM_SLICES
+static bool should_hash_preload(struct mm_struct *mm, unsigned long ea)
+{
+ /* We only prefault standard pages for now */
+ if (unlikely(get_slice_psize(mm, ea) != mm->context.user_psize))
+ return false;
+
+ return true;
+}
+#else
+static bool should_hash_preload(struct mm_struct *mm, unsigned long ea)
+{
+ return true;
+}
+#endif
+
void hash_preload(struct mm_struct *mm, unsigned long ea,
unsigned long access, unsigned long trap)
{
@@ -1208,11 +1224,8 @@ void hash_preload(struct mm_struct *mm,

BUG_ON(REGION_ID(ea) != USER_REGION_ID);

-#ifdef CONFIG_PPC_MM_SLICES
- /* We only prefault standard pages for now */
- if (unlikely(get_slice_psize(mm, ea) != mm->context.user_psize))
+ if (!should_hash_preload(mm, ea))
return;
-#endif

DBG_LOW("hash_preload(mm=%p, mm->pgdir=%p, ea=%016lx, access=%lx,"
" trap=%lx\n", mm, mm->pgd, ea, access, trap);