pagemap.h: move dir_pages() over there

That function was declared in a lot of filesystems to calculate
directory pages.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 6 insertions, 0 deletions

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 4b3736f7065c..808942d31062 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -670,4 +670,10 @@ static inline int add_to_page_cache(struct page *page,
         return error;
 }
 
+static inline unsigned long dir_pages(struct inode *inode)
+{
+        return (unsigned long)(inode->i_size + PAGE_CACHE_SIZE - 1) >>
+                               PAGE_CACHE_SHIFT;
+}
+
 #endif /* _LINUX_PAGEMAP_H */