IPoIB: P_Key change event handling

This patch causes the network interface to respond to P_Key change
events correctly.  As a result, you'll see a child interface in the
"RUNNING" state (netif_carrier_on()) only when the corresponding P_Key
is configured by the SM.  When SM removes a P_Key, the "RUNNING" state
will be disabled for the corresponding network interface.  To
implement this, I added IB_EVENT_PKEY_CHANGE event handling.  To
prevent flushing the device before the device is open by the "delay
open" mechanism, I added an additional device flag called
IPOIB_FLAG_INITIALIZED.

This also prevents the child network interface from trying to join to
multicast groups until the PKEY is configured.  We used to get error
messages like:

    ib0.f2f2: couldn't attach QP to multicast group ff12:401b:f2f2:0:0:0:ffff:ffff

in this case.  To fix this, I just check IPOIB_FLAG_OPER_UP flag in
ipoib_set_mcast_list().
Signed-off-by: Leonid Arsh <leonida@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/ulp/ipoib/ipoib.h

@@ -72,13 +72,14 @@ enum {
 	IPOIB_MAX_MCAST_QUEUE     = 3,
 
 	IPOIB_FLAG_OPER_UP 	  = 0,
-	IPOIB_FLAG_ADMIN_UP 	  = 1,
-	IPOIB_PKEY_ASSIGNED 	  = 2,
-	IPOIB_PKEY_STOP 	  = 3,
-	IPOIB_FLAG_SUBINTERFACE   = 4,
-	IPOIB_MCAST_RUN 	  = 5,
-	IPOIB_STOP_REAPER         = 6,
-	IPOIB_MCAST_STARTED       = 7,
+	IPOIB_FLAG_INITIALIZED    = 1,
+	IPOIB_FLAG_ADMIN_UP 	  = 2,
+	IPOIB_PKEY_ASSIGNED 	  = 3,
+	IPOIB_PKEY_STOP 	  = 4,
+	IPOIB_FLAG_SUBINTERFACE   = 5,
+	IPOIB_MCAST_RUN 	  = 6,
+	IPOIB_STOP_REAPER         = 7,
+	IPOIB_MCAST_STARTED       = 8,
 
 	IPOIB_MAX_BACKOFF_SECONDS = 16,
 

drivers/infiniband/ulp/ipoib/ipoib_ib.c

@@ -423,13 +423,33 @@ int ipoib_ib_dev_open(struct net_device *dev)
 	clear_bit(IPOIB_STOP_REAPER, &priv->flags);
 	queue_delayed_work(ipoib_workqueue, &priv->ah_reap_task, HZ);
 
+	set_bit(IPOIB_FLAG_INITIALIZED, &priv->flags);
+
 	return 0;
 }
 
+static void ipoib_pkey_dev_check_presence(struct net_device *dev)
+{
+	struct ipoib_dev_priv *priv = netdev_priv(dev);
+	u16 pkey_index = 0;
+
+	if (ib_find_cached_pkey(priv->ca, priv->port, priv->pkey, &pkey_index))
+		clear_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
+	else
+		set_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
+}
+
 int ipoib_ib_dev_up(struct net_device *dev)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 
+	ipoib_pkey_dev_check_presence(dev);
+
+	if (!test_bit(IPOIB_PKEY_ASSIGNED, &priv->flags)) {
+		ipoib_dbg(priv, "PKEY is not assigned.\n");
+		return 0;
+	}
+
 	set_bit(IPOIB_FLAG_OPER_UP, &priv->flags);
 
 	return ipoib_mcast_start_thread(dev);
@@ -483,6 +503,8 @@ int ipoib_ib_dev_stop(struct net_device *dev)
 	struct ipoib_tx_buf *tx_req;
 	int i;
 
+	clear_bit(IPOIB_FLAG_INITIALIZED, &priv->flags);
+
 	/*
 	 * Move our QP to the error state and then reinitialize in
 	 * when all work requests have completed or have been flushed.
@@ -587,8 +609,15 @@ void ipoib_ib_dev_flush(void *_dev)
 	struct net_device *dev = (struct net_device *)_dev;
 	struct ipoib_dev_priv *priv = netdev_priv(dev), *cpriv;
 
-	if (!test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags))
+	if (!test_bit(IPOIB_FLAG_INITIALIZED, &priv->flags) ) {
+		ipoib_dbg(priv, "Not flushing - IPOIB_FLAG_INITIALIZED not set.\n");
+		return;
+	}
+
+	if (!test_bit(IPOIB_FLAG_ADMIN_UP, &priv->flags)) {
+		ipoib_dbg(priv, "Not flushing - IPOIB_FLAG_ADMIN_UP not set.\n");
 		return;
+	}
 
 	ipoib_dbg(priv, "flushing\n");
 
@@ -632,17 +661,6 @@ void ipoib_ib_dev_cleanup(struct net_device *dev)
  * change async notification is available.
  */
 
-static void ipoib_pkey_dev_check_presence(struct net_device *dev)
-{
-	struct ipoib_dev_priv *priv = netdev_priv(dev);
-	u16 pkey_index = 0;
-
-	if (ib_find_cached_pkey(priv->ca, priv->port, priv->pkey, &pkey_index))
-		clear_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
-	else
-		set_bit(IPOIB_PKEY_ASSIGNED, &priv->flags);
-}
-
 void ipoib_pkey_poll(void *dev_ptr)
 {
 	struct net_device *dev = dev_ptr;

drivers/infiniband/ulp/ipoib/ipoib_main.c

@@ -736,6 +736,11 @@ static void ipoib_set_mcast_list(struct net_device *dev)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 
+	if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags)) {
+		ipoib_dbg(priv, "IPOIB_FLAG_OPER_UP not set");
+		return;
+	}
+
 	queue_work(ipoib_workqueue, &priv->restart_task);
 }
 

drivers/infiniband/ulp/ipoib/ipoib_verbs.c

@@ -252,6 +252,7 @@ void ipoib_event(struct ib_event_handler *handler,
 		container_of(handler, struct ipoib_dev_priv, event_handler);
 
 	if (record->event == IB_EVENT_PORT_ERR    ||
+	    record->event == IB_EVENT_PKEY_CHANGE ||
 	    record->event == IB_EVENT_PORT_ACTIVE ||
 	    record->event == IB_EVENT_LID_CHANGE  ||
 	    record->event == IB_EVENT_SM_CHANGE) {