From faacbfd3a6808bf87d8f353b42eceeaba2c78a47 Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Thu, 18 Oct 2007 23:40:04 -0700 Subject: [PATCH] pid namespaces: add support for pid namespaces hierarchy Each namespace has a parent and is characterized by its "level". Level is the number of the namespace generation. E.g. init namespace has level 0, after cloning new one it will have level 1, the next one - 2 and so on and so forth. This level is not explicitly limited. True hierarchy must have some way to find each namespace's children, but it is not used in the patches, so this ability is not added (yet). Signed-off-by: Pavel Emelyanov Cc: Oleg Nesterov Cc: Sukadev Bhattiprolu Cc: Paul Menage Cc: "Eric W. Biederman" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/pid_namespace.h | 2 ++ kernel/pid.c | 3 ++- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/include/linux/pid_namespace.h b/include/linux/pid_namespace.h index aea13ec31ab..14376ebf4ba 100644 --- a/include/linux/pid_namespace.h +++ b/include/linux/pid_namespace.h @@ -21,6 +21,8 @@ struct pid_namespace { int last_pid; struct task_struct *child_reaper; struct kmem_cache *pid_cachep; + int level; + struct pid_namespace *parent; }; extern struct pid_namespace init_pid_ns; diff --git a/kernel/pid.c b/kernel/pid.c index bb0785109d3..c7346fb801f 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -67,7 +67,8 @@ struct pid_namespace init_pid_ns = { [ 0 ... PIDMAP_ENTRIES-1] = { ATOMIC_INIT(BITS_PER_PAGE), NULL } }, .last_pid = 0, - .child_reaper = &init_task + .level = 0, + .child_reaper = &init_task, }; int is_global_init(struct task_struct *tsk)