[PATCH] Permit multiple inclusion of linux/pagevec.h

Make it possible to include linux/pagevec.h multiple times without
incurring errors due to duplicate definitions.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/pagevec.h

@@ -5,6 +5,9 @@
  * pages.  A pagevec is a multipage container which is used for that.
  */
 
+#ifndef _LINUX_PAGEVEC_H
+#define _LINUX_PAGEVEC_H
+
 /* 14 pointers + two long's align the pagevec structure to a power of two */
 #define PAGEVEC_SIZE	14
 
@@ -83,3 +86,5 @@ static inline void pagevec_lru_add(struct pagevec *pvec)
 	if (pagevec_count(pvec))
 		__pagevec_lru_add(pvec);
 }
+
+#endif /* _LINUX_PAGEVEC_H */