netns: Coexist with the sysfs limitations v2
To make testing of the network namespace simpler allow
the network namespace code and the sysfs code to be
compiled and run at the same time. To do this only
virtual devices are allowed in the additional network
namespaces and those virtual devices are not placed
in the kobject tree.
Since virtual devices don't actually do anything interesting
hardware wise that needs device management there should
be no loss in keeping them out of the kobject tree and
by implication sysfs. The gain in ease of testing
and code coverage should be significant.
Changelog:
v2: As pointed out by Benjamin Thery it only makes sense to call
device_rename in the initial network namespace for now.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Benjamin Thery <benjamin.thery@bull.net>
Tested-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/Kconfig b/net/Kconfig
index d789d79..8c3d97c 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -27,7 +27,7 @@
config NET_NS
bool "Network namespace support"
default n
- depends on EXPERIMENTAL && !SYSFS && NAMESPACES
+ depends on EXPERIMENTAL && NAMESPACES
help
Allow user space to create what appear to be multiple instances
of the network stack.
diff --git a/net/core/dev.c b/net/core/dev.c
index d9038e3..3a2b8be 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -924,10 +924,15 @@
strlcpy(dev->name, newname, IFNAMSIZ);
rollback:
- ret = device_rename(&dev->dev, dev->name);
- if (ret) {
- memcpy(dev->name, oldname, IFNAMSIZ);
- return ret;
+ /* For now only devices in the initial network namespace
+ * are in sysfs.
+ */
+ if (net == &init_net) {
+ ret = device_rename(&dev->dev, dev->name);
+ if (ret) {
+ memcpy(dev->name, oldname, IFNAMSIZ);
+ return ret;
+ }
}
write_lock_bh(&dev_base_lock);
@@ -4460,6 +4465,15 @@
if (dev->features & NETIF_F_NETNS_LOCAL)
goto out;
+#ifdef CONFIG_SYSFS
+ /* Don't allow real devices to be moved when sysfs
+ * is enabled.
+ */
+ err = -EINVAL;
+ if (dev->dev.parent)
+ goto out;
+#endif
+
/* Ensure the device has been registrered */
err = -EINVAL;
if (dev->reg_state != NETREG_REGISTERED)
@@ -4517,6 +4531,8 @@
*/
dev_addr_discard(dev);
+ netdev_unregister_kobject(dev);
+
/* Actually switch the network namespace */
dev_net_set(dev, net);
@@ -4533,7 +4549,6 @@
}
/* Fixup kobjects */
- netdev_unregister_kobject(dev);
err = netdev_register_kobject(dev);
WARN_ON(err);
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index 92d6b94..85cb8bd 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -476,6 +476,10 @@
struct device *dev = &(net->dev);
kobject_get(&dev->kobj);
+
+ if (dev_net(net) != &init_net)
+ return;
+
device_del(dev);
}
@@ -501,6 +505,9 @@
#endif
#endif /* CONFIG_SYSFS */
+ if (dev_net(net) != &init_net)
+ return 0;
+
return device_add(dev);
}