[PATCH 20/23] ipc: Add ipc namespaces into ns_idr

[Kirill Tkhai]

Now they are exposed in /proc/namespace/ directory.

Signed-off-by: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx>
---
 ipc/namespace.c |   13 ++++++++++++-
 ipc/shm.c       |    1 +
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/ipc/namespace.c b/ipc/namespace.c
index 7bd0766ddc3b..ce6f87dd6d08 100644
--- a/ipc/namespace.c
+++ b/ipc/namespace.c
@@ -63,8 +63,17 @@ static struct ipc_namespace *create_ipc_ns(struct user_namespace *user_ns,
 	msg_init_ns(ns);
 	shm_init_ns(ns);
 
+	err = ns_idr_register(&ns->ns);
+	if (err)
+		goto fail_exit;
+
 	return ns;
 
+fail_exit:
+	mq_put_mnt(ns);
+	sem_exit_ns(ns);
+	msg_exit_ns(ns);
+	shm_exit_ns(ns);
 fail_put:
 	put_user_ns(ns->user_ns);
 	ns_free_inum(&ns->ns);
@@ -117,6 +126,8 @@ void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids,
 
 static void free_ipc_ns(struct ipc_namespace *ns)
 {
+	ns_idr_unregister(&ns->ns);
+
 	/* mq_put_mnt() waits for a grace period as kern_unmount()
 	 * uses synchronize_rcu().
 	 */
@@ -128,7 +139,7 @@ static void free_ipc_ns(struct ipc_namespace *ns)
 	dec_ipc_namespaces(ns->ucounts);
 	put_user_ns(ns->user_ns);
 	ns_free_inum(&ns->ns);
-	kfree(ns);
+	kfree(ns); /* RCU grace period wait is done in mq_put_mnt */
 }
 
 static LLIST_HEAD(free_ipc_list);
diff --git a/ipc/shm.c b/ipc/shm.c
index 6cf24a5994ec..9e83556d9dcb 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -137,6 +137,7 @@ void shm_exit_ns(struct ipc_namespace *ns)
 static int __init ipc_ns_init(void)
 {
 	shm_init_ns(&init_ipc_ns);
+	WARN_ON(ns_idr_register(&init_ipc_ns.ns) < 0);
 	return 0;
 }