Hi,
On 05/07/2018 03:10 PM, Sridhar Samudrala wrote:
>
> Signed-off-by: Sridhar Samudrala <sridhar.samudr...@intel.com>
> ---
> MAINTAINERS | 7 +
> include/linux/netdevice.h | 16 +
> include/net/net_failover.h | 52 +++
> net/Kconfig | 10 +
> net/core/Makefile | 1 +
> net/core/net_failover.c | 1044
> ++++++++++++++++++++++++++++++++++++++++++++
> 6 files changed, 1130 insertions(+)
> create mode 100644 include/net/net_failover.h
> create mode 100644 net/core/net_failover.c
> diff --git a/net/Kconfig b/net/Kconfig
> index b62089fb1332..0540856676de 100644
> --- a/net/Kconfig
> +++ b/net/Kconfig
> @@ -429,6 +429,16 @@ config MAY_USE_DEVLINK
> config PAGE_POOL
> bool
>
> +config NET_FAILOVER
> + tristate "Failover interface"
> + default m
Need some justification for default m (as opposed to n).
> + help
> + This provides a generic interface for paravirtual drivers to listen
> + for netdev register/unregister/link change events from pci ethernet
PCI
> + devices with the same MAC and takeover their datapath. This also
> + enables live migration of a VM with direct attached VF by failing
> + over to the paravirtual datapath when the VF is unplugged.
> +
> endif # if NET
>
> # Used by archs to tell that they support BPF JIT compiler plus which
> flavour.
> diff --git a/net/core/net_failover.c b/net/core/net_failover.c
> new file mode 100644
> index 000000000000..8d60e74e3034
> --- /dev/null
> +++ b/net/core/net_failover.c
> @@ -0,0 +1,1044 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (c) 2018, Intel Corporation. */
> +
> +/* A common module to handle registrations and notifications for paravirtual
> + * drivers to enable accelerated datapath and support VF live migration.
> + *
> + * The notifier and event handling code is based on netvsc driver and
> failover
> + * netdev management routines are based on bond/team driver.
> + *
> + */
> +/**
> + * net_failover_create - Create and register a failover instance
> + *
> + * @dev: standby netdev
* @standby_dev: standby netdev
> + *
> + * Creates a failover netdev and registers a failover instance for a standby
> + * netdev. Used by paravirtual drivers that use 3-netdev model.
> + * The failover netdev acts as a master device and controls 2 slave devices -
> + * the original standby netdev and a VF netdev with the same MAC gets
> + * registered as primary netdev.
> + *
> + * Return: pointer to failover instance
> + */
> +struct net_failover *net_failover_create(struct net_device *standby_dev)
> +{
> + struct device *dev = standby_dev->dev.parent;
> + struct net_device *failover_dev;
> + struct net_failover *failover;
> + int err;
> +
> + /* Alloc at least 2 queues, for now we are going with 16 assuming
> + * that VF devices being enslaved won't have too many queues.
> + */
> + failover_dev = alloc_etherdev_mq(sizeof(struct net_failover_info), 16);
> + if (!failover_dev) {
> + dev_err(dev, "Unable to allocate failover_netdev!\n");
> + return ERR_PTR(-ENOMEM);
> + }
> +
> + dev_net_set(failover_dev, dev_net(standby_dev));
> + SET_NETDEV_DEV(failover_dev, dev);
> +
> + failover_dev->netdev_ops = &failover_dev_ops;
> + failover_dev->ethtool_ops = &failover_ethtool_ops;
> +
> + /* Initialize the device options */
> + failover_dev->priv_flags |= IFF_UNICAST_FLT | IFF_NO_QUEUE;
> + failover_dev->priv_flags &= ~(IFF_XMIT_DST_RELEASE |
> + IFF_TX_SKB_SHARING);
> +
> + /* don't acquire failover netdev's netif_tx_lock when transmitting */
> + failover_dev->features |= NETIF_F_LLTX;
> +
> + /* Don't allow failover devices to change network namespaces. */
> + failover_dev->features |= NETIF_F_NETNS_LOCAL;
> +
> + failover_dev->hw_features = FAILOVER_VLAN_FEATURES |
> + NETIF_F_HW_VLAN_CTAG_TX |
> + NETIF_F_HW_VLAN_CTAG_RX |
> + NETIF_F_HW_VLAN_CTAG_FILTER;
> +
> + failover_dev->hw_features |= NETIF_F_GSO_ENCAP_ALL;
> + failover_dev->features |= failover_dev->hw_features;
> +
> + memcpy(failover_dev->dev_addr, standby_dev->dev_addr,
> + failover_dev->addr_len);
> +
> + failover_dev->min_mtu = standby_dev->min_mtu;
> + failover_dev->max_mtu = standby_dev->max_mtu;
> +
> + err = register_netdev(failover_dev);
> + if (err) {
> + dev_err(dev, "Unable to register failover_dev!\n");
> + goto err_register_netdev;
> + }
> +
> + netif_carrier_off(failover_dev);
> +
> + failover = net_failover_register(failover_dev, NULL);
> + if (IS_ERR(failover))
> + goto err_failover_register;
> +
> + return failover;
> +
> +err_failover_register:
> + unregister_netdev(failover_dev);
> +err_register_netdev:
> + free_netdev(failover_dev);
> +
> + return ERR_PTR(err);
> +}
> +EXPORT_SYMBOL_GPL(net_failover_create);
--
~Randy
