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>
This commit is contained in:
Thomas Falcon 2017-06-12 12:35:04 -05:00 committed by David S. Miller
parent 725757aee0
commit 40c9db8ad8
2 changed files with 48 additions and 0 deletions

View File

@ -295,6 +295,8 @@
#define H_DISABLE_ALL_VIO_INTS 0x0A
#define H_DISABLE_VIO_INTERRUPT 0x0B
#define H_ENABLE_VIO_INTERRUPT 0x0C
#define H_GET_SESSION_TOKEN 0x19
#define H_SESSION_ERR_DETECTED 0x1A
/* Platform specific hcalls, used by KVM */

View File

@ -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);