From bc451f2058238013e1cdf4acd443c01734d332f0 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 30 Mar 2010 11:31:25 -0700 Subject: kobj: Add basic infrastructure for dealing with namespaces. Move complete knowledge of namespaces into the kobject layer so we can use that information when reporting kobjects to userspace. Signed-off-by: Eric W. Biederman Signed-off-by: Greg Kroah-Hartman --- include/linux/kobject.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'include/linux/kobject.h') diff --git a/include/linux/kobject.h b/include/linux/kobject.h index 3950d3c2850d..d9456f69904f 100644 --- a/include/linux/kobject.h +++ b/include/linux/kobject.h @@ -108,6 +108,8 @@ struct kobj_type { void (*release)(struct kobject *kobj); const struct sysfs_ops *sysfs_ops; struct attribute **default_attrs; + const struct kobj_ns_type_operations *(*child_ns_type)(struct kobject *kobj); + const void *(*namespace)(struct kobject *kobj); }; struct kobj_uevent_env { @@ -134,6 +136,30 @@ struct kobj_attribute { extern const struct sysfs_ops kobj_sysfs_ops; +enum kobj_ns_type { + KOBJ_NS_TYPE_NONE = 0, + KOBJ_NS_TYPES +}; + +struct sock; +struct kobj_ns_type_operations { + enum kobj_ns_type type; + const void *(*current_ns)(void); + const void *(*netlink_ns)(struct sock *sk); + const void *(*initial_ns)(void); +}; + +int kobj_ns_type_register(const struct kobj_ns_type_operations *ops); +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); +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); + + /** * struct kset - a set of kobjects of a specific type, belonging to a specific subsystem. * -- cgit v1.2.3 From be867b194a3ae3c680c29521287ae49b4d44d420 Mon Sep 17 00:00:00 2001 From: "Serge E. Hallyn" Date: Mon, 3 May 2010 16:23:15 -0500 Subject: sysfs: Comment sysfs directory tagging logic Add some in-line comments to explain the new infrastructure, which was introduced to support sysfs directory tagging with namespaces. I think an overall description someplace might be good too, but it didn't really seem to fit into Documentation/filesystems/sysfs.txt, which appears more geared toward users, rather than maintainers, of sysfs. (Tejun, please let me know if I can make anything clearer or failed altogether to comment something that should be commented.) Signed-off-by: Serge E. Hallyn Cc: Eric W. Biederman Cc: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- include/linux/kobject.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'include/linux/kobject.h') diff --git a/include/linux/kobject.h b/include/linux/kobject.h index d9456f69904f..b60d2dfe4e69 100644 --- a/include/linux/kobject.h +++ b/include/linux/kobject.h @@ -136,12 +136,23 @@ struct kobj_attribute { extern const struct sysfs_ops kobj_sysfs_ops; +/* + * Namespace types which are used to tag kobjects and sysfs entries. + * Network namespace will likely be the first. + */ enum kobj_ns_type { KOBJ_NS_TYPE_NONE = 0, KOBJ_NS_TYPES }; struct sock; + +/* + * Callbacks so sysfs can determine namespaces + * @current_ns: return 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) + */ struct kobj_ns_type_operations { enum kobj_ns_type type; const void *(*current_ns)(void); -- cgit v1.2.3 From 608b4b9548dedf4185ca47edcaae4bff2ceb62de Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Tue, 4 May 2010 17:36:45 -0700 Subject: netns: Teach network device kobjects which namespace they are in. The problem. Network devices show up in sysfs and with the network namespace active multiple devices with the same name can show up in the same directory, ouch! To avoid that problem and allow existing applications in network namespaces to see the same interface that is currently presented in sysfs, this patch enables the tagging directory support in sysfs. By using the network namespace pointers as tags to separate out the the sysfs directory entries we ensure that we don't have conflicts in the directories and applications only see a limited set of the network devices. Signed-off-by: Eric W. Biederman Acked-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/linux/kobject.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/kobject.h') diff --git a/include/linux/kobject.h b/include/linux/kobject.h index b60d2dfe4e69..cf343a852534 100644 --- a/include/linux/kobject.h +++ b/include/linux/kobject.h @@ -142,6 +142,7 @@ extern const struct sysfs_ops kobj_sysfs_ops; */ enum kobj_ns_type { KOBJ_NS_TYPE_NONE = 0, + KOBJ_NS_TYPE_NET, KOBJ_NS_TYPES }; -- cgit v1.2.3