@@ -232,9 +232,144 @@ del_device_store(const struct bus_type *bus, const char *buf, size_t count)
}
static BUS_ATTR_WO(del_device);
+static ssize_t link_device_store(const struct bus_type *bus, const char *buf, size_t count)
+{
+ struct netdevsim *nsim_a, *nsim_b, *peer;
+ struct net_device *dev_a, *dev_b;
+ unsigned int ifidx_a, ifidx_b;
+ int netnsfd_a, netnsfd_b, err;
+ struct net *ns_a, *ns_b;
+
+ err = sscanf(buf, "%d:%u %d:%u", &netnsfd_a, &ifidx_a, &netnsfd_b, &ifidx_b);
+ if (err != 4) {
+ pr_err("Format for linking two devices is \"netnsfd_a:ifidx_a netnsfd_b:ifidx_b\" (int uint int uint).\n");
+ return -EINVAL;
+ }
+
+ ns_a = get_net_ns_by_fd(netnsfd_a);
+ if (IS_ERR(ns_a)) {
+ pr_err("Could not find netns with fd: %d\n", netnsfd_a);
+ return -EINVAL;
+ }
+
+ ns_b = get_net_ns_by_fd(netnsfd_b);
+ if (IS_ERR(ns_b)) {
+ pr_err("Could not find netns with fd: %d\n", netnsfd_b);
+ return -EINVAL;
+ }
+
+ err = -EINVAL;
+ rtnl_lock();
+ dev_a = __dev_get_by_index(ns_a, ifidx_a);
+ if (!dev_a) {
+ pr_err("Could not find device with ifindex %u in netnsfd %d\n", ifidx_a, netnsfd_a);
+ goto out_put_netns_a;
+ }
+
+ if (!netdev_is_nsim(dev_a)) {
+ pr_err("Device with ifindex %u in netnsfd %d is not a netdevsim\n", ifidx_a, netnsfd_a);
+ goto out_put_netns_a;
+ }
+
+ dev_b = __dev_get_by_index(ns_b, ifidx_b);
+ if (!dev_b) {
+ pr_err("Could not find device with ifindex %u in netnsfd %d\n", ifidx_b, netnsfd_b);
+ goto out_put_netns_b;
+ }
+
+ if (!netdev_is_nsim(dev_b)) {
+ pr_err("Device with ifindex %u in netnsfd %d is not a netdevsim\n", ifidx_b, netnsfd_b);
+ goto out_put_netns_b;
+ }
+
+ if (dev_a == dev_b) {
+ pr_err("Cannot link a netdevsim to itself\n");
+ goto out_put_netns_b;
+ }
+
+ err = 0;
+ nsim_a = netdev_priv(dev_a);
+ peer = rtnl_dereference(nsim_a->peer);
+ if (peer) {
+ pr_err("Netdevsim %d:%u is already linked\n", netnsfd_a, ifidx_a);
+ goto out_put_netns_b;
+ }
+
+ nsim_b = netdev_priv(dev_b);
+ peer = rtnl_dereference(nsim_b->peer);
+ if (peer) {
+ pr_err("Netdevsim %d:%u is already linked\n", netnsfd_b, ifidx_b);
+ goto out_put_netns_b;
+ }
+
+ rcu_assign_pointer(nsim_a->peer, nsim_b);
+ rcu_assign_pointer(nsim_b->peer, nsim_a);
+
+out_put_netns_b:
+ put_net(ns_b);
+out_put_netns_a:
+ put_net(ns_a);
+ rtnl_unlock();
+
+ return !err ? count : err;
+}
+static BUS_ATTR_WO(link_device);
+
+static ssize_t unlink_device_store(const struct bus_type *bus, const char *buf, size_t count)
+{
+ struct netdevsim *nsim, *peer;
+ struct net_device *dev;
+ unsigned int ifidx;
+ int netnsfd, err;
+ struct net *ns;
+
+ err = sscanf(buf, "%u:%u", &netnsfd, &ifidx);
+ if (err != 2) {
+ pr_err("Format for unlinking a device is \"netnsfd:ifidx\" (int uint).\n");
+ return -EINVAL;
+ }
+
+ ns = get_net_ns_by_fd(netnsfd);
+ if (IS_ERR(ns)) {
+ pr_err("Could not find netns with fd: %d\n", netnsfd);
+ return -EINVAL;
+ }
+
+ err = -EINVAL;
+ rtnl_lock();
+ dev = __dev_get_by_index(ns, ifidx);
+ if (!dev) {
+ pr_err("Could not find device with ifindex %u in netnsfd %d\n", ifidx, netnsfd);
+ goto out_put_netns;
+ }
+
+ if (!netdev_is_nsim(dev)) {
+ pr_err("Device with ifindex %u in netnsfd %d is not a netdevsim\n", ifidx, netnsfd);
+ goto out_put_netns;
+ }
+
+ err = 0;
+ nsim = netdev_priv(dev);
+ peer = rtnl_dereference(nsim->peer);
+ if (!peer)
+ goto out_put_netns;
+
+ RCU_INIT_POINTER(nsim->peer, NULL);
+ RCU_INIT_POINTER(peer->peer, NULL);
+
+out_put_netns:
+ put_net(ns);
+ rtnl_unlock();
+
+ return !err ? count : err;
+}
+static BUS_ATTR_WO(unlink_device);
+
static struct attribute *nsim_bus_attrs[] = {
&bus_attr_new_device.attr,
&bus_attr_del_device.attr,
+ &bus_attr_link_device.attr,
+ &bus_attr_unlink_device.attr,
NULL
};
ATTRIBUTE_GROUPS(nsim_bus);
@@ -413,8 +413,13 @@ nsim_create(struct nsim_dev *nsim_dev, struct nsim_dev_port *nsim_dev_port)
void nsim_destroy(struct netdevsim *ns)
{
struct net_device *dev = ns->netdev;
+ struct netdevsim *peer;
rtnl_lock();
+ peer = rtnl_dereference(ns->peer);
+ if (peer)
+ RCU_INIT_POINTER(peer->peer, NULL);
+ RCU_INIT_POINTER(ns->peer, NULL);
unregister_netdevice(dev);
if (nsim_dev_port_is_pf(ns->nsim_dev_port)) {
nsim_macsec_teardown(ns);
@@ -427,6 +432,11 @@ void nsim_destroy(struct netdevsim *ns)
free_netdev(dev);
}
+bool netdev_is_nsim(struct net_device *dev)
+{
+ return dev->netdev_ops == &nsim_netdev_ops;
+}
+
static int nsim_validate(struct nlattr *tb[], struct nlattr *data[],
struct netlink_ext_ack *extack)
{
@@ -125,11 +125,13 @@ struct netdevsim {
} udp_ports;
struct nsim_ethtool ethtool;
+ struct netdevsim __rcu *peer;
};
struct netdevsim *
nsim_create(struct nsim_dev *nsim_dev, struct nsim_dev_port *nsim_dev_port);
void nsim_destroy(struct netdevsim *ns);
+bool netdev_is_nsim(struct net_device *dev);
void nsim_ethtool_init(struct netdevsim *ns);
Add two netdevsim bus attribute to sysfs: /sys/bus/netdevsim/link_device /sys/bus/netdevsim/unlink_device Writing "A M B N" to link_device will link netdevsim M in netnsid A with netdevsim N in netnsid B. Writing "A M" to unlink_device will unlink netdevsim M in netnsid A from its peer, if any. rtnl_lock is taken to ensure nothing changes during the linking. Signed-off-by: David Wei <dw@davidwei.uk> --- drivers/net/netdevsim/bus.c | 135 ++++++++++++++++++++++++++++++ drivers/net/netdevsim/netdev.c | 10 +++ drivers/net/netdevsim/netdevsim.h | 2 + 3 files changed, 147 insertions(+)