From 485ac57bc1238719b1508f91b0f9eeda4a3c84bb Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Thu, 30 Oct 2008 23:55:16 -0700 Subject: [PATCH] netns: add register_pernet_gen_subsys/unregister_pernet_gen_subsys netns ops which are registered with register_pernet_gen_device() are shutdown strictly before those which are registered with register_pernet_subsys(). Sometimes this leads to opposite (read: buggy) shutdown ordering between two modules. Add register_pernet_gen_subsys()/unregister_pernet_gen_subsys() for modules which aren't elite enough for entry in struct net, and which can't use register_pernet_gen_device(). PPTP conntracking module is such one. Signed-off-by: Alexey Dobriyan Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- include/net/net_namespace.h | 2 ++ net/core/net_namespace.c | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 34 insertions(+) diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 708009be88b6..700c53a3c6fa 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -214,6 +214,8 @@ struct pernet_operations { extern int register_pernet_subsys(struct pernet_operations *); extern void unregister_pernet_subsys(struct pernet_operations *); +extern int register_pernet_gen_subsys(int *id, struct pernet_operations *); +extern void unregister_pernet_gen_subsys(int id, struct pernet_operations *); extern int register_pernet_device(struct pernet_operations *); extern void unregister_pernet_device(struct pernet_operations *); extern int register_pernet_gen_device(int *id, struct pernet_operations *); diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index f1d07b5c1e17..1895a4ca9c4f 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -325,6 +325,38 @@ void unregister_pernet_subsys(struct pernet_operations *module) } EXPORT_SYMBOL_GPL(unregister_pernet_subsys); +int register_pernet_gen_subsys(int *id, struct pernet_operations *ops) +{ + int rv; + + mutex_lock(&net_mutex); +again: + rv = ida_get_new_above(&net_generic_ids, 1, id); + if (rv < 0) { + if (rv == -EAGAIN) { + ida_pre_get(&net_generic_ids, GFP_KERNEL); + goto again; + } + goto out; + } + rv = register_pernet_operations(first_device, ops); + if (rv < 0) + ida_remove(&net_generic_ids, *id); + mutex_unlock(&net_mutex); +out: + return rv; +} +EXPORT_SYMBOL_GPL(register_pernet_gen_subsys); + +void unregister_pernet_gen_subsys(int id, struct pernet_operations *ops) +{ + mutex_lock(&net_mutex); + unregister_pernet_operations(ops); + ida_remove(&net_generic_ids, id); + mutex_unlock(&net_mutex); +} +EXPORT_SYMBOL_GPL(unregister_pernet_gen_subsys); + /** * register_pernet_device - register a network namespace device * @ops: pernet operations structure for the subsystem -- 2.20.1