kernel/linux.git/net/core/fib_notifier.c, branch v6.18.21

net: do not acquire rtnl in fib_seq_sum()

2024-10-11T22:35:05+00:00

After we made sure no fib_seq_read() handlers needs RTNL anymore, we can remove RTNL from fib_seq_sum(). Note that after RTNL was dropped, fib_seq_sum() result was possibly outdated anyway. Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Reviewed-by: David Ahern Link: https://patch.msgid.link/20241009184405.3752829-6-edumazet@google.com Signed-off-by: Jakub Kicinski

net: fib_notifier: propagate extack down to the notifier block callback

2019-10-04T18:10:56+00:00

Since errors are propagated all the way up to the caller, propagate possible extack of the caller all the way down to the notifier block callback. Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller

net: fib_notifier: make FIB notifier per-netns

2019-10-04T18:10:55+00:00

Currently all users of FIB notifier only cares about events in init_net. Later in this patchset, users get interested in other namespaces too. However, for every registered block user is interested only about one namespace. Make the FIB notifier registration per-netns and avoid unnecessary calls of notifier block for other namespaces. Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller

net: fib_notifier: move fib_notifier_ops from struct net into per-net struct

2019-09-07T15:28:22+00:00

No need for fib_notifier_ops to be in struct net. It is used only by fib_notifier as a private data. Use net_generic to introduce per-net fib_notifier struct and move fib_notifier_ops there. Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller

net: Fix fib notifer to return errno

2018-03-29T18:10:30+00:00

Notifier handlers use notifier_from_errno to convert any potential error to an encoded format. As a consequence the other side, call_fib_notifier{s} in this case, needs to use notifier_to_errno to return the error from the handler back to its caller. Signed-off-by: David Ahern Reviewed-by: Ido Schimmel Signed-off-by: David S. Miller

net: Introduce net_rwsem to protect net_namespace_list

2018-03-29T17:47:53+00:00

rtnl_lock() is used everywhere, and contention is very high. When someone wants to iterate over alive net namespaces, he/she has no a possibility to do that without exclusive lock. But the exclusive rtnl_lock() in such places is overkill, and it just increases the contention. Yes, there is already for_each_net_rcu() in kernel, but it requires rcu_read_lock(), and this can't be sleepable. Also, sometimes it may be need really prevent net_namespace_list growth, so for_each_net_rcu() is not fit there. This patch introduces new rw_semaphore, which will be used instead of rtnl_mutex to protect net_namespace_list. It is sleepable and allows not-exclusive iterations over net namespaces list. It allows to stop using rtnl_lock() in several places (what is made in next patches) and makes less the time, we keep rtnl_mutex. Here we just add new lock, while the explanation of we can remove rtnl_lock() there are in next patches. Fine grained locks generally are better, then one big lock, so let's do that with net_namespace_list, while the situation allows that. Signed-off-by: Kirill Tkhai Signed-off-by: David S. Miller

net: Drop pernet_operations::async

2018-03-27T17:18:09+00:00

Synchronous pernet_operations are not allowed anymore. All are asynchronous. So, drop the structure member. Signed-off-by: Kirill Tkhai Signed-off-by: David S. Miller

net: Convert fib_* pernet_operations, registered via subsys_initcall

2018-02-13T15:36:07+00:00

Both of them create and initialize lists, which are not touched by another foreing pernet_operations. Signed-off-by: Kirill Tkhai Acked-by: Andrei Vagin Signed-off-by: David S. Miller

net: Protect iterations over net::fib_notifier_ops in fib_seq_sum()

2017-11-15T05:01:30+00:00

There is at least unlocked deletion of net->ipv4.fib_notifier_ops from net::fib_notifier_ops: ip_fib_net_exit() rtnl_unlock() fib4_notifier_exit() fib_notifier_ops_unregister(net->ipv4.notifier_ops) list_del_rcu(&ops->list) So fib_seq_sum() can't use rtnl_lock() only for protection. The possible solution could be to use rtnl_lock() in fib_notifier_ops_unregister(), but this adds a possible delay during net namespace creation, so we better use rcu_read_lock() till someone really needs the mutex (if that happens). Signed-off-by: Kirill Tkhai Signed-off-by: David S. Miller

fib_notifier: exit_net cleanup check added

2017-11-14T06:45:53+00:00

Be sure that fib_notifier_ops list initilized in net_init hook was return to initial state. Signed-off-by: Vasily Averin Signed-off-by: David S. Miller