ibmvnic: Client-initiated failover
The IBM vNIC protocol provides support for the user to initiate
a failover from the client LPAR in case the current backing infrastructure
is deemed inadequate or in an error state.
Support for two H_VIOCTL sub-commands for vNIC devices are required
to implement this function. These commands are H_GET_SESSION_TOKEN
and H_SESSION_ERR_DETECTED.
"[H_GET_SESSION_TOKEN] is used to obtain a session token from a VNIC client
adapter. This token is opaque to the caller and is intended to be used in
tandem with the SESSION_ERROR_DETECTED vioctl subfunction."
"[H_SESSION_ERR_DETECTED] is used to report that the currently active
backing device for a VNIC client adapter is behaving poorly, and that
the hypervisor should attempt to fail over to a different backing device,
if one is available."
To provide tools access to this functionality the vNIC driver creates a
sysfs file that, when written to, will send a request to pHyp to failover
to a different backing device.
Signed-off-by: Thomas Falcon <tlfalcon@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@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 7d84e20..fd3ef30 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -3656,6 +3656,8 @@ static int ibmvnic_init(struct ibmvnic_adapter *adapter)
return rc;
}
+static struct device_attribute dev_attr_failover;
+
static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id)
{
struct ibmvnic_adapter *adapter;
@@ -3712,9 +3714,16 @@ static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id)
netdev->mtu = adapter->req_mtu - ETH_HLEN;
+ rc = device_create_file(&dev->dev, &dev_attr_failover);
+ if (rc) {
+ free_netdev(netdev);
+ return rc;
+ }
+
rc = register_netdev(netdev);
if (rc) {
dev_err(&dev->dev, "failed to register netdev rc=%d\n", rc);
+ device_remove_file(&dev->dev, &dev_attr_failover);
free_netdev(netdev);
return rc;
}
@@ -3740,12 +3749,49 @@ static int ibmvnic_remove(struct vio_dev *dev)
adapter->state = VNIC_REMOVED;
mutex_unlock(&adapter->reset_lock);
+ device_remove_file(&dev->dev, &dev_attr_failover);
free_netdev(netdev);
dev_set_drvdata(&dev->dev, NULL);
return 0;
}
+static ssize_t failover_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct net_device *netdev = dev_get_drvdata(dev);
+ struct ibmvnic_adapter *adapter = netdev_priv(netdev);
+ unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
+ __be64 session_token;
+ long rc;
+
+ if (!sysfs_streq(buf, "1"))
+ return -EINVAL;
+
+ rc = plpar_hcall(H_VIOCTL, retbuf, adapter->vdev->unit_address,
+ H_GET_SESSION_TOKEN, 0, 0, 0);
+ if (rc) {
+ netdev_err(netdev, "Couldn't retrieve session token, rc %ld\n",
+ rc);
+ return -EINVAL;
+ }
+
+ session_token = (__be64)retbuf[0];
+ netdev_dbg(netdev, "Initiating client failover, session id %llx\n",
+ be64_to_cpu(session_token));
+ rc = plpar_hcall_norets(H_VIOCTL, adapter->vdev->unit_address,
+ H_SESSION_ERR_DETECTED, session_token, 0, 0);
+ if (rc) {
+ netdev_err(netdev, "Client initiated failover failed, rc %ld\n",
+ rc);
+ return -EINVAL;
+ }
+
+ return count;
+}
+
+static DEVICE_ATTR(failover, 0200, NULL, failover_store);
+
static unsigned long ibmvnic_get_desired_dma(struct vio_dev *vdev)
{
struct net_device *netdev = dev_get_drvdata(&vdev->dev);