diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 2d654c1..c0d0e3e 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -17,6 +17,7 @@
  */
 
 #include <linux/fs.h>
+#include <linux/slab.h>
 #include <linux/sched.h>
 #include <linux/writeback.h>
 #include <linux/pagemap.h>