btrfs: use round_up wrapper in num_extent_pages

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index d8382a4a7f46e8677914252c85136afcf94a71e6..7a3c15b55f2b4139f6dc95675f873b00a3dda40d 100644 (file)
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -442,8 +442,8 @@ void wait_on_extent_buffer_writeback(struct extent_buffer *eb);
 
 static inline unsigned long num_extent_pages(const struct extent_buffer *eb)
 {
-       return ((eb->start + eb->len + PAGE_SIZE - 1) >> PAGE_SHIFT) -
-               (eb->start >> PAGE_SHIFT);
+       return (round_up(eb->start + eb->len, PAGE_SIZE) >> PAGE_SHIFT) -
+              (eb->start >> PAGE_SHIFT);
 }
 
 static inline void extent_buffer_get(struct extent_buffer *eb)