diff options
| -rw-r--r-- | fs/sysfs/mount.c | 37 | ||||
| -rw-r--r-- | fs/sysfs/sysfs.h | 2 | ||||
| -rw-r--r-- | include/linux/kobject_ns.h | 10 | ||||
| -rw-r--r-- | include/linux/sysfs.h | 7 | ||||
| -rw-r--r-- | include/net/net_namespace.h | 10 | ||||
| -rw-r--r-- | lib/kobject.c | 26 | ||||
| -rw-r--r-- | net/core/net-sysfs.c | 23 | ||||
| -rw-r--r-- | net/core/net_namespace.c | 12 |
8 files changed, 55 insertions, 72 deletions
diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c index 2668957..e34f0d9 100644 --- a/fs/sysfs/mount.c +++ b/fs/sysfs/mount.c @@ -95,6 +95,14 @@ static int sysfs_set_super(struct super_block *sb, void *data) return error; } +static void free_sysfs_super_info(struct sysfs_super_info *info) +{ + int type; + for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) + kobj_ns_drop(type, info->ns[type]); + kfree(info); +} + static struct dentry *sysfs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) { @@ -108,11 +116,11 @@ static struct dentry *sysfs_mount(struct file_system_type *fs_type, return ERR_PTR(-ENOMEM); for (type = KOBJ_NS_TYPE_NONE; type < KOBJ_NS_TYPES; type++) - info->ns[type] = kobj_ns_current(type); + info->ns[type] = kobj_ns_grab_current(type); sb = sget(fs_type, sysfs_test_super, sysfs_set_super, info); if (IS_ERR(sb) || sb->s_fs_info != info) - kfree(info); + free_sysfs_super_info(info); if (IS_ERR(sb)) return ERR_CAST(sb); if (!sb->s_root) { @@ -131,12 +139,11 @@ static struct dentry *sysfs_mount(struct file_system_type *fs_type, static void sysfs_kill_sb(struct super_block *sb) { struct sysfs_super_info *info = sysfs_info(sb); - /* Remove the superblock from fs_supers/s_instances * so we can't find it, before freeing sysfs_super_info. */ kill_anon_super(sb); - kfree(info); + free_sysfs_super_info(info); } static struct file_system_type sysfs_fs_type = { @@ -145,28 +152,6 @@ static struct file_system_type sysfs_fs_type = { .kill_sb = sysfs_kill_sb, }; -void sysfs_exit_ns(enum kobj_ns_type type, const void *ns) -{ - struct super_block *sb; - - mutex_lock(&sysfs_mutex); - spin_lock(&sb_lock); - list_for_each_entry(sb, &sysfs_fs_type.fs_supers, s_instances) { - struct sysfs_super_info *info = sysfs_info(sb); - /* - * If we see a superblock on the fs_supers/s_instances - * list the unmount has not completed and sb->s_fs_info - * points to a valid struct sysfs_super_info. - */ - /* Ignore superblocks with the wrong ns */ - if (info->ns[type] != ns) - continue; - info->ns[type] = NULL; - } - spin_unlock(&sb_lock); - mutex_unlock(&sysfs_mutex); -} - int __init sysfs_init(void) { int err = -ENOMEM; diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index 3d28af31..2ed2404 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -136,7 +136,7 @@ struct sysfs_addrm_cxt { * instance). */ struct sysfs_super_info { - const void *ns[KOBJ_NS_TYPES]; + void *ns[KOBJ_NS_TYPES]; }; #define sysfs_info(SB) ((struct sysfs_super_info *)(SB->s_fs_info)) extern struct sysfs_dirent sysfs_root; diff --git a/include/linux/kobject_ns.h b/include/linux/kobject_ns.h index 82cb5bf..f66b065 100644 --- a/include/linux/kobject_ns.h +++ b/include/linux/kobject_ns.h @@ -32,15 +32,17 @@ enum kobj_ns_type { /* * Callbacks so sysfs can determine namespaces - * @current_ns: return calling task's namespace + * @grab_current_ns: return a new reference to calling task's namespace * @netlink_ns: return namespace to which a sock belongs (right?) * @initial_ns: return the initial namespace (i.e. init_net_ns) + * @drop_ns: drops a reference to namespace */ struct kobj_ns_type_operations { enum kobj_ns_type type; - const void *(*current_ns)(void); + void *(*grab_current_ns)(void); const void *(*netlink_ns)(struct sock *sk); const void *(*initial_ns)(void); + void (*drop_ns)(void *); }; int kobj_ns_type_register(const struct kobj_ns_type_operations *ops); @@ -48,9 +50,9 @@ int kobj_ns_type_registered(enum kobj_ns_type type); const struct kobj_ns_type_operations *kobj_child_ns_ops(struct kobject *parent); const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj); -const void *kobj_ns_current(enum kobj_ns_type type); +void *kobj_ns_grab_current(enum kobj_ns_type type); const void *kobj_ns_netlink(enum kobj_ns_type type, struct sock *sk); const void *kobj_ns_initial(enum kobj_ns_type type); -void kobj_ns_exit(enum kobj_ns_type type, const void *ns); +void kobj_ns_drop(enum kobj_ns_type type, void *ns); #endif /* _LINUX_KOBJECT_NS_H */ diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index c3acda6..e2696d7 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -177,9 +177,6 @@ struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd, struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd); void sysfs_put(struct sysfs_dirent *sd); -/* Called to clear a ns tag when it is no longer valid */ -void sysfs_exit_ns(enum kobj_ns_type type, const void *tag); - int __must_check sysfs_init(void); #else /* CONFIG_SYSFS */ @@ -338,10 +335,6 @@ static inline void sysfs_put(struct sysfs_dirent *sd) { } -static inline void sysfs_exit_ns(int type, const void *tag) -{ -} - static inline int __must_check sysfs_init(void) { return 0; diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 2bf9ed9..aef430d 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -35,8 +35,11 @@ struct netns_ipvs; #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS) struct net { + atomic_t passive; /* To decided when the network + * namespace should be freed. + */ atomic_t count; /* To decided when the network - * namespace should be freed. + * namespace should be shut down. */ #ifdef NETNS_REFCNT_DEBUG atomic_t use_count; /* To track references we @@ -154,6 +157,9 @@ int net_eq(const struct net *net1, const struct net *net2) { return net1 == net2; } + +extern void net_drop_ns(void *); + #else static inline struct net *get_net(struct net *net) @@ -175,6 +181,8 @@ int net_eq(const struct net *net1, const struct net *net2) { return 1; } + +#define net_drop_ns NULL #endif diff --git a/lib/kobject.c b/lib/kobject.c index 82dc34c..640bd98 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -948,14 +948,14 @@ const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj) } -const void *kobj_ns_current(enum kobj_ns_type type) +void *kobj_ns_grab_current(enum kobj_ns_type type) { - const void *ns = NULL; + void *ns = NULL; spin_lock(&kobj_ns_type_lock); if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) && kobj_ns_ops_tbl[type]) - ns = kobj_ns_ops_tbl[type]->current_ns(); + ns = kobj_ns_ops_tbl[type]->grab_current_ns(); spin_unlock(&kobj_ns_type_lock); return ns; @@ -987,23 +987,15 @@ const void *kobj_ns_initial(enum kobj_ns_type type) return ns; } -/* - * kobj_ns_exit - invalidate a namespace tag - * - * @type: the namespace type (i.e. KOBJ_NS_TYPE_NET) - * @ns: the actual namespace being invalidated - * - * This is called when a tag is no longer valid. For instance, - * when a network namespace exits, it uses this helper to - * make sure no sb's sysfs_info points to the now-invalidated - * netns. - */ -void kobj_ns_exit(enum kobj_ns_type type, const void *ns) +void kobj_ns_drop(enum kobj_ns_type type, void *ns) { - sysfs_exit_ns(type, ns); + spin_lock(&kobj_ns_type_lock); + if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) && + kobj_ns_ops_tbl[type] && kobj_ns_ops_tbl[type]->drop_ns) + kobj_ns_ops_tbl[type]->drop_ns(ns); + spin_unlock(&kobj_ns_type_lock); } - EXPORT_SYMBOL(kobject_get); EXPORT_SYMBOL(kobject_put); EXPORT_SYMBOL(kobject_del); diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c index 11b98bc..33d2a1f 100644 --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -1179,9 +1179,14 @@ static void remove_queue_kobjects(struct net_device *net) #endif } -static const void *net_current_ns(void) +static void *net_grab_current_ns(void) { - return current->nsproxy->net_ns; + struct net *ns = current->nsproxy->net_ns; +#ifdef CONFIG_NET_NS + if (ns) + atomic_inc(&ns->passive); +#endif + return ns; } static const void *net_initial_ns(void) @@ -1196,22 +1201,13 @@ static const void *net_netlink_ns(struct sock *sk) struct kobj_ns_type_operations net_ns_type_operations = { .type = KOBJ_NS_TYPE_NET, - .current_ns = net_current_ns, + .grab_current_ns = net_grab_current_ns, .netlink_ns = net_netlink_ns, .initial_ns = net_initial_ns, + .drop_ns = net_drop_ns, }; EXPORT_SYMBOL_GPL(net_ns_type_operations); -static void net_kobj_ns_exit(struct net *net) -{ - kobj_ns_exit(KOBJ_NS_TYPE_NET, net); -} - -static struct pernet_operations kobj_net_ops = { - .exit = net_kobj_ns_exit, -}; - - #ifdef CONFIG_HOTPLUG static int netdev_uevent(struct device *d, struct kobj_uevent_env *env) { @@ -1339,6 +1335,5 @@ EXPORT_SYMBOL(netdev_class_remove_file); int netdev_kobject_init(void) { kobj_ns_type_register(&net_ns_type_operations); - register_pernet_subsys(&kobj_net_ops); return class_register(&net_class); } diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 6c6b86d..cdcbc3c 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -128,6 +128,7 @@ static __net_init int setup_net(struct net *net) LIST_HEAD(net_exit_list); atomic_set(&net->count, 1); + atomic_set(&net->passive, 1); #ifdef NETNS_REFCNT_DEBUG atomic_set(&net->use_count, 0); @@ -210,6 +211,13 @@ static void net_free(struct net *net) kmem_cache_free(net_cachep, net); } +void net_drop_ns(void *p) +{ + struct net *ns = p; + if (ns && atomic_dec_and_test(&ns->passive)) + net_free(ns); +} + struct net *copy_net_ns(unsigned long flags, struct net *old_net) { struct net *net; @@ -230,7 +238,7 @@ struct net *copy_net_ns(unsigned long flags, struct net *old_net) } mutex_unlock(&net_mutex); if (rv < 0) { - net_free(net); + net_drop_ns(net); return ERR_PTR(rv); } return net; @@ -286,7 +294,7 @@ static void cleanup_net(struct work_struct *work) /* Finally it is safe to free my network namespace structure */ list_for_each_entry_safe(net, tmp, &net_exit_list, exit_list) { list_del_init(&net->exit_list); - net_free(net); + net_drop_ns(net); } } static DECLARE_WORK(net_cleanup_work, cleanup_net); |
