ibmvnic: Handle backing device failover and reinitialization

An upcoming feature of IBM VNIC protocol is the ability to configure
redundant backing devices for a VNIC client. In case of a failure
on the current backing device, the driver will receive a signal
from the hypervisor indicating that a failover will occur. The driver
will then wait for a message from the backing device before
establishing a new connection.

Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 88f3c85..b942108 100644 (file)
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -203,7 +203,8 @@ static void free_long_term_buff(struct ibmvnic_adapter *adapter,
        struct device *dev = &adapter->vdev->dev;
 
        dma_free_coherent(dev, ltb->size, ltb->buff, ltb->addr);
-       send_request_unmap(adapter, ltb->map_id);
+       if (!adapter->failover)
+               send_request_unmap(adapter, ltb->map_id);
 }
 
 static int alloc_rx_pool(struct ibmvnic_adapter *adapter,
@@ -522,7 +523,8 @@ static int ibmvnic_close(struct net_device *netdev)
        for (i = 0; i < adapter->req_rx_queues; i++)
                napi_disable(&adapter->napi[i]);
 
-       netif_tx_stop_all_queues(netdev);
+       if (!adapter->failover)
+               netif_tx_stop_all_queues(netdev);
 
        if (adapter->bounce_buffer) {
                if (!dma_mapping_error(dev, adapter->bounce_buffer_dma)) {
@@ -3280,6 +3282,10 @@ static void ibmvnic_handle_crq(union ibmvnic_crq *crq,
                        rc = ibmvnic_send_crq_init(adapter);
                        if (rc)
                                dev_err(dev, "Error sending init rc=%ld\n", rc);
+               } else if (gen_crq->cmd == IBMVNIC_DEVICE_FAILOVER) {
+                       dev_info(dev, "Backing device failover detected\n");
+                       netif_carrier_off(netdev);
+                       adapter->failover = true;
                } else {
                        /* The adapter lost the connection */
                        dev_err(dev, "Virtual Adapter failed (rc=%d)\n",
@@ -3615,8 +3621,18 @@ static void handle_crq_init_rsp(struct work_struct *work)
        struct device *dev = &adapter->vdev->dev;
        struct net_device *netdev = adapter->netdev;
        unsigned long timeout = msecs_to_jiffies(30000);
+       bool restart = false;
        int rc;
 
+       if (adapter->failover) {
+               release_sub_crqs(adapter);
+               if (netif_running(netdev)) {
+                       netif_tx_disable(netdev);
+                       ibmvnic_close(netdev);
+                       restart = true;
+               }
+       }
+
        send_version_xchg(adapter);
        reinit_completion(&adapter->init_done);
        if (!wait_for_completion_timeout(&adapter->init_done, timeout)) {
@@ -3645,6 +3661,17 @@ static void handle_crq_init_rsp(struct work_struct *work)
 
        netdev->real_num_tx_queues = adapter->req_tx_queues;
 
+       if (adapter->failover) {
+               adapter->failover = false;
+               if (restart) {
+                       rc = ibmvnic_open(netdev);
+                       if (rc)
+                               goto restart_failed;
+               }
+               netif_carrier_on(netdev);
+               return;
+       }
+
        rc = register_netdev(netdev);
        if (rc) {
                dev_err(dev,
@@ -3655,6 +3682,8 @@ static void handle_crq_init_rsp(struct work_struct *work)
 
        return;
 
+restart_failed:
+       dev_err(dev, "Failed to restart ibmvnic, rc=%d\n", rc);
 register_failed:
        release_sub_crqs(adapter);
 task_failed:
@@ -3692,6 +3721,7 @@ static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id)
        dev_set_drvdata(&dev->dev, netdev);
        adapter->vdev = dev;
        adapter->netdev = netdev;
+       adapter->failover = false;
 
        ether_addr_copy(adapter->mac_addr, mac_addr_p);
        ether_addr_copy(netdev->dev_addr, adapter->mac_addr);

diff --git a/drivers/net/ethernet/ibm/ibmvnic.h b/drivers/net/ethernet/ibm/ibmvnic.h
index e82898f..bfc84c7 100644 (file)
--- a/drivers/net/ethernet/ibm/ibmvnic.h
+++ b/drivers/net/ethernet/ibm/ibmvnic.h
@@ -830,6 +830,7 @@ enum ibmvfc_crq_format {
        IBMVNIC_CRQ_INIT                 = 0x01,
        IBMVNIC_CRQ_INIT_COMPLETE        = 0x02,
        IBMVNIC_PARTITION_MIGRATED       = 0x06,
+       IBMVNIC_DEVICE_FAILOVER          = 0x08,
 };
 
 struct ibmvnic_crq_queue {
@@ -1047,4 +1048,5 @@ struct ibmvnic_adapter {
        u8 map_id;
 
        struct work_struct vnic_crq_init;
+       bool failover;
 };