[PATCH 07/29] asm-generic: improve the flush_dcache_page stub

[Christoph Hellwig <hch@xxxxxx>]

There is a magic ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE cpp symbol that
guards non-stub availability of flush_dcache_pagge.  Use that to
check if flush_dcache_pagg is implemented.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
 include/asm-generic/cacheflush.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/asm-generic/cacheflush.h b/include/asm-generic/cacheflush.h
index bf9bb83e9fc8d..bbbb4d4ef6516 100644
--- a/include/asm-generic/cacheflush.h
+++ b/include/asm-generic/cacheflush.h
@@ -2,8 +2,6 @@
 #ifndef _ASM_GENERIC_CACHEFLUSH_H
 #define _ASM_GENERIC_CACHEFLUSH_H
 
-#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
-
 /*
  * The cache doesn't need to be flushed when TLB entries change when
  * the cache is mapped to physical memory, not virtual memory
@@ -42,12 +40,14 @@ static inline void flush_cache_page(struct vm_area_struct *vma,
 }
 #endif
 
-#ifndef flush_dcache_page
+#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
 static inline void flush_dcache_page(struct page *page)
 {
 }
+#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 0
 #endif
 
+
 #ifndef flush_dcache_mmap_lock
 static inline void flush_dcache_mmap_lock(struct address_space *mapping)
 {
-- 
2.26.2