include/linux/cleancache.h: Clean up code

Let cleancache_fs_enabled() call cleancache_fs_enabled_mapping()
directly.

Remove redundant variable ret in cleancache_get_page().

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

include/linux/cleancache.h

@@ -48,14 +48,14 @@ extern void __cleancache_invalidate_fs(struct super_block *);
 
 #ifdef CONFIG_CLEANCACHE
 #define cleancache_enabled (1)
-static inline bool cleancache_fs_enabled(struct page *page)
-{
-	return page->mapping->host->i_sb->cleancache_poolid >= 0;
-}
 static inline bool cleancache_fs_enabled_mapping(struct address_space *mapping)
 {
 	return mapping->host->i_sb->cleancache_poolid >= 0;
 }
+static inline bool cleancache_fs_enabled(struct page *page)
+{
+	return cleancache_fs_enabled_mapping(page->mapping);
+}
 #else
 #define cleancache_enabled (0)
 #define cleancache_fs_enabled(_page) (0)
@@ -89,11 +89,9 @@ static inline void cleancache_init_shared_fs(struct super_block *sb)
 
 static inline int cleancache_get_page(struct page *page)
 {
-	int ret = -1;
-
 	if (cleancache_enabled && cleancache_fs_enabled(page))
-		ret = __cleancache_get_page(page);
-	return ret;
+		return __cleancache_get_page(page);
+	return -1;
 }
 
 static inline void cleancache_put_page(struct page *page)