RDMA/core: Add a netlink command to change net namespace of rdma device

Provide an option to change the net namespace of a rdma device through a
netlink command. When multiple rdma devices exists in a system, and when
containers are used, this will limit rdma device visibility to a specified
net namespace.

An example command to change net namespace of mlx5_1 device to the
previously created net namespace 'foo' is:

$ ip netns add foo
$ rdma dev set mlx5_1 netns foo

Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This commit is contained in:
Parav Pandit 2019-04-15 13:22:51 +03:00 committed by Jason Gunthorpe
parent decbc7a6b0
commit 2e5b8a0116
4 changed files with 70 additions and 7 deletions

View file

@ -350,4 +350,6 @@ int ib_port_register_module_stat(struct ib_device *device, u8 port_num,
const char *name);
void ib_port_unregister_module_stat(struct kobject *kobj);
int ib_device_set_netns_put(struct sk_buff *skb,
struct ib_device *dev, u32 ns_fd);
#endif /* _CORE_PRIV_H */

View file

@ -1452,9 +1452,9 @@ static int rdma_dev_change_netns(struct ib_device *device, struct net *cur_net,
mutex_lock(&device->unregistration_lock);
/*
* If a device not under ib_device_get() or the unregistration_lock
* the namespace can be changed, or it can be unregistered. Check
* again under the lock.
* If a device not under ib_device_get() or if the unregistration_lock
* is not held, the namespace can be changed, or it can be unregistered.
* Check again under the lock.
*/
if (refcount_read(&device->refcount) == 0 ||
!net_eq(cur_net, read_pnet(&device->coredev.rdma_net))) {
@ -1471,12 +1471,12 @@ static int rdma_dev_change_netns(struct ib_device *device, struct net *cur_net,
*/
write_pnet(&device->coredev.rdma_net, net);
down_read(&devices_rwsem);
/*
* Currently rdma devices are system wide unique. So the device name
* is guaranteed free in the new namespace. Publish the new namespace
* at the sysfs level.
*/
down_read(&devices_rwsem);
ret = device_rename(&device->dev, dev_name(&device->dev));
up_read(&devices_rwsem);
if (ret) {
@ -1488,7 +1488,7 @@ static int rdma_dev_change_netns(struct ib_device *device, struct net *cur_net,
}
ret2 = enable_device_and_get(device);
if (ret2)
if (ret2) {
/*
* This shouldn't really happen, but if it does, let the user
* retry at later point. So don't disable the device.
@ -1496,7 +1496,9 @@ static int rdma_dev_change_netns(struct ib_device *device, struct net *cur_net,
dev_warn(&device->dev,
"%s: Couldn't re-enable device after namespace change\n",
__func__);
}
kobject_uevent(&device->dev.kobj, KOBJ_ADD);
ib_device_put(device);
out:
mutex_unlock(&device->unregistration_lock);
@ -1505,6 +1507,50 @@ static int rdma_dev_change_netns(struct ib_device *device, struct net *cur_net,
return ret2;
}
int ib_device_set_netns_put(struct sk_buff *skb,
struct ib_device *dev, u32 ns_fd)
{
struct net *net;
int ret;
net = get_net_ns_by_fd(ns_fd);
if (IS_ERR(net)) {
ret = PTR_ERR(net);
goto net_err;
}
if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN)) {
ret = -EPERM;
goto ns_err;
}
/*
* Currently supported only for those providers which support
* disassociation and don't do port specific sysfs init. Once a
* port_cleanup infrastructure is implemented, this limitation will be
* removed.
*/
if (!dev->ops.disassociate_ucontext || dev->ops.init_port ||
ib_devices_shared_netns) {
ret = -EOPNOTSUPP;
goto ns_err;
}
get_device(&dev->dev);
ib_device_put(dev);
ret = rdma_dev_change_netns(dev, current->nsproxy->net_ns, net);
put_device(&dev->dev);
put_net(net);
return ret;
ns_err:
put_net(net);
net_err:
ib_device_put(dev);
return ret;
}
static struct pernet_operations rdma_dev_net_ops = {
.init = rdma_dev_init_net,
.exit = rdma_dev_exit_net,

View file

@ -119,6 +119,7 @@ static const struct nla_policy nldev_policy[RDMA_NLDEV_ATTR_MAX] = {
[RDMA_NLDEV_SYS_ATTR_NETNS_MODE] = { .type = NLA_U8 },
[RDMA_NLDEV_ATTR_DEV_PROTOCOL] = { .type = NLA_NUL_STRING,
.len = RDMA_NLDEV_ATTR_ENTRY_STRLEN },
[RDMA_NLDEV_NET_NS_FD] = { .type = NLA_U32 },
};
static int put_driver_name_print_type(struct sk_buff *msg, const char *name,
@ -691,9 +692,20 @@ static int nldev_set_doit(struct sk_buff *skb, struct nlmsghdr *nlh,
nla_strlcpy(name, tb[RDMA_NLDEV_ATTR_DEV_NAME],
IB_DEVICE_NAME_MAX);
err = ib_device_rename(device, name);
goto done;
}
if (tb[RDMA_NLDEV_NET_NS_FD]) {
u32 ns_fd;
ns_fd = nla_get_u32(tb[RDMA_NLDEV_NET_NS_FD]);
err = ib_device_set_netns_put(skb, device, ns_fd);
goto put_done;
}
done:
ib_device_put(device);
put_done:
return err;
}
@ -909,7 +921,6 @@ static int _nldev_res_get_dumpit(struct ib_device *device,
nlmsg_cancel(skb, nlh);
goto out;
}
nlmsg_end(skb, nlh);
idx++;

View file

@ -469,12 +469,16 @@ enum rdma_nldev_attr {
* either shared or exclusive among multiple net namespaces.
*/
RDMA_NLDEV_SYS_ATTR_NETNS_MODE, /* u8 */
/*
* Device protocol, e.g. ib, iw, usnic, roce and opa
*/
RDMA_NLDEV_ATTR_DEV_PROTOCOL, /* string */
/*
* File descriptor handle of the net namespace object
*/
RDMA_NLDEV_NET_NS_FD, /* u32 */
/*
* Always the end
*/