vhost/scsi: Don't reinvent the wheel but use existing llist API

Although llist provides proper APIs, they are not used. Make them used.
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Acked-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/vhost/scsi.c

@@ -496,14 +496,12 @@ static void vhost_scsi_evt_work(struct vhost_work *work)
 	struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 					vs_event_work);
 	struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
-	struct vhost_scsi_evt *evt;
+	struct vhost_scsi_evt *evt, *t;
 	struct llist_node *llnode;
 
 	mutex_lock(&vq->mutex);
 	llnode = llist_del_all(&vs->vs_event_list);
-	while (llnode) {
-		evt = llist_entry(llnode, struct vhost_scsi_evt, list);
-		llnode = llist_next(llnode);
+	llist_for_each_entry_safe(evt, t, llnode, list) {
 		vhost_scsi_do_evt_work(vs, evt);
 		vhost_scsi_free_evt(vs, evt);
 	}
@@ -529,10 +527,7 @@ static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 
 	bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 	llnode = llist_del_all(&vs->vs_completion_list);
-	while (llnode) {
-		cmd = llist_entry(llnode, struct vhost_scsi_cmd,
-				     tvc_completion_list);
-		llnode = llist_next(llnode);
+	llist_for_each_entry(cmd, llnode, tvc_completion_list) {
 		se_cmd = &cmd->tvc_se_cmd;
 
 		pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,