[PATCH] memory leak in current BK

Well I didn't test that very well.  __page_cache_release() is doing a
__free_page() on a zero-ref page, so __free_pages() sends the refcount
negative and doesn't free it.  With patch #8, page_cache_release()
almost never frees pages, but it must have been leaking a little bit.
Lucky it showed up.

This fixes it, and also adds a missing PageReserved test in put_page().
Which makes put_page() identical to page_cache_release(), but there are
header file woes.  I'll fix that up later.

include/linux/mm.h

@@ -199,11 +199,12 @@ struct page {
 #define page_count(p)		atomic_read(&(p)->count)
 #define set_page_count(p,v) 	atomic_set(&(p)->count, v)
 extern void FASTCALL(__page_cache_release(struct page *));
-#define put_page(p)					\
-	do {						\
-		if (put_page_testzero(p))		\
-			__page_cache_release(p);	\
+#define put_page(p)							\
+	do {								\
+		if (!PageReserved(p) && put_page_testzero(p))		\
+			__page_cache_release(p);			\
 	} while (0)
+void FASTCALL(__free_pages_ok(struct page *page, unsigned int order));
 
 /*
  * Multiple processes may "see" the same page. E.g. for untouched

mm/page_alloc.c

@@ -80,8 +80,7 @@ static inline int bad_range(zone_t *zone, struct page *page)
  * -- wli
  */
 
-static void FASTCALL(__free_pages_ok (struct page *page, unsigned int order));
-static void __free_pages_ok (struct page *page, unsigned int order)
+void __free_pages_ok (struct page *page, unsigned int order)
 {
 	unsigned long index, page_idx, mask, flags;
 	free_area_t *area;

mm/swap.c

@@ -89,7 +89,7 @@ void __page_cache_release(struct page *page)
 			del_page_from_inactive_list(page);
 		spin_unlock_irqrestore(&_pagemap_lru_lock, flags);
 	}
-	__free_page(page);
+	__free_pages_ok(page, 0);
 }
 
 /*