X-Git-Url: http://pilppa.org/gitweb/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fnsproxy.c;h=79f871bc0ef40026e111df575622cbc6b11031c3;hb=058dc3342b71ffb3531c4f9df7c35f943f392b8d;hp=f1decd21a534c248054bef7c1c6f9f6ec7da072c;hpb=ebf8889bd1fe3615991ff4494635d237280652a2;p=linux-2.6-omap-h63xx.git diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c index f1decd21a53..79f871bc0ef 100644 --- a/kernel/nsproxy.c +++ b/kernel/nsproxy.c @@ -26,19 +26,6 @@ static struct kmem_cache *nsproxy_cachep; struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); -static inline void get_nsproxy(struct nsproxy *ns) -{ - atomic_inc(&ns->count); -} - -void get_task_namespaces(struct task_struct *tsk) -{ - struct nsproxy *ns = tsk->nsproxy; - if (ns) { - get_nsproxy(ns); - } -} - /* * creates a copy of "orig" with refcount 1. */ @@ -87,7 +74,7 @@ static struct nsproxy *create_new_namespaces(unsigned long flags, goto out_ipc; } - new_nsp->pid_ns = copy_pid_ns(flags, tsk->nsproxy->pid_ns); + new_nsp->pid_ns = copy_pid_ns(flags, task_active_pid_ns(tsk)); if (IS_ERR(new_nsp->pid_ns)) { err = PTR_ERR(new_nsp->pid_ns); goto out_pid; @@ -142,7 +129,8 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk) get_nsproxy(old_ns); - if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | CLONE_NEWUSER | CLONE_NEWNET))) + if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | + CLONE_NEWUSER | CLONE_NEWPID | CLONE_NEWNET))) return 0; if (!capable(CAP_SYS_ADMIN)) { @@ -156,7 +144,14 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk) goto out; } + err = ns_cgroup_clone(tsk); + if (err) { + put_nsproxy(new_ns); + goto out; + } + tsk->nsproxy = new_ns; + out: put_nsproxy(old_ns); return err; @@ -196,15 +191,49 @@ int unshare_nsproxy_namespaces(unsigned long unshare_flags, *new_nsp = create_new_namespaces(unshare_flags, current, new_fs ? new_fs : current->fs); - if (IS_ERR(*new_nsp)) + if (IS_ERR(*new_nsp)) { err = PTR_ERR(*new_nsp); + goto out; + } + + err = ns_cgroup_clone(current); + if (err) + put_nsproxy(*new_nsp); + +out: return err; } +void switch_task_namespaces(struct task_struct *p, struct nsproxy *new) +{ + struct nsproxy *ns; + + might_sleep(); + + ns = p->nsproxy; + + rcu_assign_pointer(p->nsproxy, new); + + if (ns && atomic_dec_and_test(&ns->count)) { + /* + * wait for others to get what they want from this nsproxy. + * + * cannot release this nsproxy via the call_rcu() since + * put_mnt_ns() will want to sleep + */ + synchronize_rcu(); + free_nsproxy(ns); + } +} + +void exit_task_namespaces(struct task_struct *p) +{ + switch_task_namespaces(p, NULL); +} + static int __init nsproxy_cache_init(void) { - nsproxy_cachep = kmem_cache_create("nsproxy", sizeof(struct nsproxy), - 0, SLAB_PANIC, NULL); + nsproxy_cachep = KMEM_CACHE(nsproxy, SLAB_PANIC); return 0; }