diff --git a/fs/hpfs/anode.c b/fs/hpfs/anode.c
index 1aa88c4..6a2f04b 100644
--- a/fs/hpfs/anode.c
+++ b/fs/hpfs/anode.c
@@ -353,7 +353,7 @@
 }
 
 int hpfs_ea_write(struct super_block *s, secno a, int ano, unsigned pos,
-	     unsigned len, char *buf)
+	     unsigned len, const char *buf)
 {
 	struct buffer_head *bh;
 	char *data;