diff --git a/fs/9p/cache.c b/fs/9p/cache.c
index e777961..0dbe0d1 100644
--- a/fs/9p/cache.c
+++ b/fs/9p/cache.c
@@ -22,6 +22,7 @@
 
 #include <linux/jiffies.h>
 #include <linux/file.h>
+#include <linux/slab.h>
 #include <linux/stat.h>
 #include <linux/sched.h>
 #include <linux/fs.h>