3 files changed, 100 insertions, 13 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib.h b/drivers/infiniband/ulp/ipoib/ipoib.h
index caec8e9c4666..c51f618f6120 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib.h
+++ b/drivers/infiniband/ulp/ipoib/ipoib.h
@@ -392,6 +392,7 @@ struct ipoib_dev_priv {
 	struct ipoib_ethtool_st ethtool;
 	struct timer_list poll_timer;
 	unsigned max_send_sge;
+	bool sm_fullmember_sendonly_support;
 };
 
 struct ipoib_ah {
@@ -476,6 +477,7 @@ void ipoib_reap_ah(struct work_struct *work);
 
 void ipoib_mark_paths_invalid(struct net_device *dev);
 void ipoib_flush_paths(struct net_device *dev);
+int ipoib_check_sm_sendonly_fullmember_support(struct ipoib_dev_priv *priv);
 struct ipoib_dev_priv *ipoib_intf_alloc(const char *format);
 
 int ipoib_ib_dev_init(struct net_device *dev, struct ib_device *ca, int port);
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 80807d6e5c4c..8bf1859ebed4 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -117,6 +117,8 @@ int ipoib_open(struct net_device *dev)
 
 	set_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags);
 
+	priv->sm_fullmember_sendonly_support = false;
+
 	if (ipoib_ib_dev_open(dev)) {
 		if (!test_bit(IPOIB_PKEY_ASSIGNED, &priv->flags))
 			return 0;
@@ -629,6 +631,77 @@ void ipoib_mark_paths_invalid(struct net_device *dev)
 	spin_unlock_irq(&priv->lock);
 }
 
+struct classport_info_context {
+	struct ipoib_dev_priv	*priv;
+	struct completion	done;
+	struct ib_sa_query	*sa_query;
+};
+
+static void classport_info_query_cb(int status, struct ib_class_port_info *rec,
+				    void *context)
+{
+	struct classport_info_context *cb_ctx = context;
+	struct ipoib_dev_priv *priv;
+
+	WARN_ON(!context);
+
+	priv = cb_ctx->priv;
+
+	if (status || !rec) {
+		pr_debug("device: %s failed query classport_info status: %d\n",
+			 priv->dev->name, status);
+		/* keeps the default, will try next mcast_restart */
+		priv->sm_fullmember_sendonly_support = false;
+		goto out;
+	}
+
+	if (ib_get_cpi_capmask2(rec) &
+	    IB_SA_CAP_MASK2_SENDONLY_FULL_MEM_SUPPORT) {
+		pr_debug("device: %s enabled fullmember-sendonly for sendonly MCG\n",
+			 priv->dev->name);
+		priv->sm_fullmember_sendonly_support = true;
+	} else {
+		pr_debug("device: %s disabled fullmember-sendonly for sendonly MCG\n",
+			 priv->dev->name);
+		priv->sm_fullmember_sendonly_support = false;
+	}
+
+out:
+	complete(&cb_ctx->done);
+}
+
+int ipoib_check_sm_sendonly_fullmember_support(struct ipoib_dev_priv *priv)
+{
+	struct classport_info_context *callback_context;
+	int ret;
+
+	callback_context = kmalloc(sizeof(*callback_context), GFP_KERNEL);
+	if (!callback_context)
+		return -ENOMEM;
+
+	callback_context->priv = priv;
+	init_completion(&callback_context->done);
+
+	ret = ib_sa_classport_info_rec_query(&ipoib_sa_client,
+					     priv->ca, priv->port, 3000,
+					     GFP_KERNEL,
+					     classport_info_query_cb,
+					     callback_context,
+					     &callback_context->sa_query);
+	if (ret < 0) {
+		pr_info("%s failed to send ib_sa_classport_info query, ret: %d\n",
+			priv->dev->name, ret);
+		kfree(callback_context);
+		return ret;
+	}
+
+	/* waiting for the callback to finish before returnning */
+	wait_for_completion(&callback_context->done);
+	kfree(callback_context);
+
+	return ret;
+}
+
 void ipoib_flush_paths(struct net_device *dev)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
diff --git a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
index 25889311b1e9..fc3e50e8e391 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_multicast.c
@@ -64,6 +64,9 @@ struct ipoib_mcast_iter {
 	unsigned int       send_only;
 };
 
+/* join state that allows creating mcg with sendonly member request */
+#define SENDONLY_FULLMEMBER_JOIN	8
+
 /*
  * This should be called with the priv->lock held
  */
@@ -326,12 +329,23 @@ void ipoib_mcast_carrier_on_task(struct work_struct *work)
 	struct ipoib_dev_priv *priv = container_of(work, struct ipoib_dev_priv,
 						   carrier_on_task);
 	struct ib_port_attr attr;
+	int ret;
 
 	if (ib_query_port(priv->ca, priv->port, &attr) ||
 	    attr.state != IB_PORT_ACTIVE) {
 		ipoib_dbg(priv, "Keeping carrier off until IB port is active\n");
 		return;
 	}
+	/*
+	 * Check if can send sendonly MCG's with sendonly-fullmember join state.
+	 * It done here after the successfully join to the broadcast group,
+	 * because the broadcast group must always be joined first and is always
+	 * re-joined if the SM changes substantially.
+	 */
+	ret = ipoib_check_sm_sendonly_fullmember_support(priv);
+	if (ret < 0)
+		pr_debug("%s failed query sm support for sendonly-fullmember (ret: %d)\n",
+			 priv->dev->name, ret);
 
 	/*
 	 * Take rtnl_lock to avoid racing with ipoib_stop() and
@@ -515,22 +529,20 @@ static int ipoib_mcast_join(struct net_device *dev, struct ipoib_mcast *mcast)
 		rec.hop_limit	  = priv->broadcast->mcmember.hop_limit;
 
 		/*
-		 * Send-only IB Multicast joins do not work at the core
-		 * IB layer yet, so we can't use them here.  However,
-		 * we are emulating an Ethernet multicast send, which
-		 * does not require a multicast subscription and will
-		 * still send properly.  The most appropriate thing to
+		 * Send-only IB Multicast joins work at the core IB layer but
+		 * require specific SM support.
+		 * We can use such joins here only if the current SM supports that feature.
+		 * However, if not, we emulate an Ethernet multicast send,
+		 * which does not require a multicast subscription and will
+		 * still send properly. The most appropriate thing to
 		 * do is to create the group if it doesn't exist as that
 		 * most closely emulates the behavior, from a user space
-		 * application perspecitive, of Ethernet multicast
-		 * operation.  For now, we do a full join, maybe later
-		 * when the core IB layers support send only joins we
-		 * will use them.
+		 * application perspective, of Ethernet multicast operation.
 		 */
-#if 0
-		if (test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags))
-			rec.join_state = 4;
-#endif
+		if (test_bit(IPOIB_MCAST_FLAG_SENDONLY, &mcast->flags) &&
+		    priv->sm_fullmember_sendonly_support)
+			/* SM supports sendonly-fullmember, otherwise fallback to full-member */
+			rec.join_state = SENDONLY_FULLMEMBER_JOIN;
 	}
 	spin_unlock_irq(&priv->lock);