ceph: use kref for ceph_msg

Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/msgpool.c b/fs/ceph/msgpool.c
index 7599b33..ad5482c 100644
--- a/fs/ceph/msgpool.c
+++ b/fs/ceph/msgpool.c
@@ -165,7 +165,7 @@
 {
 	spin_lock(&pool->lock);
 	if (pool->num < pool->min) {
-		ceph_msg_get(msg);   /* retake a single ref */
+		kref_set(&msg->kref, 1);  /* retake a single ref */
 		list_add(&msg->list_head, &pool->msgs);
 		pool->num++;
 		dout("msgpool_put %p reclaim %p, now %d/%d\n", pool, msg,