asm-generic, mm: pgtable: consolidate zero page helpers
We have two different implementation of is_zero_pfn() and my_zero_pfn()
helpers: for architectures with and without zero page coloring.
Let's consolidate them in <asm-generic/pgtable.h>.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h
index b36ce40..284e808 100644
--- a/include/asm-generic/pgtable.h
+++ b/include/asm-generic/pgtable.h
@@ -449,6 +449,32 @@
unsigned long size);
#endif
+#ifdef __HAVE_COLOR_ZERO_PAGE
+static inline int is_zero_pfn(unsigned long pfn)
+{
+ extern unsigned long zero_pfn;
+ unsigned long offset_from_zero_pfn = pfn - zero_pfn;
+ return offset_from_zero_pfn <= (zero_page_mask >> PAGE_SHIFT);
+}
+
+static inline unsigned long my_zero_pfn(unsigned long addr)
+{
+ return page_to_pfn(ZERO_PAGE(addr));
+}
+#else
+static inline int is_zero_pfn(unsigned long pfn)
+{
+ extern unsigned long zero_pfn;
+ return pfn == zero_pfn;
+}
+
+static inline unsigned long my_zero_pfn(unsigned long addr)
+{
+ extern unsigned long zero_pfn;
+ return zero_pfn;
+}
+#endif
+
#ifdef CONFIG_MMU
#ifndef CONFIG_TRANSPARENT_HUGEPAGE
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 4b80bad..4af4f0b 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -516,14 +516,6 @@
}
#endif
-#ifndef my_zero_pfn
-static inline unsigned long my_zero_pfn(unsigned long addr)
-{
- extern unsigned long zero_pfn;
- return zero_pfn;
-}
-#endif
-
/*
* Multiple processes may "see" the same page. E.g. for untouched
* mappings of /dev/null, all processes see the same page full of
