X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=include%2Flinux%2Fnsproxy.h;h=7b370c7cfeffb27db00d71fa2127381abdbfd518;hb=74dbbdd7fdc11763f4698d2f3e684cf4446951e6;hp=9c2e0ad508dbf455483cfa9c2fb8512e2c0f7e5b;hpb=4865ecf1315b450ab3317a745a6678c04d311e40;p=safe%2Fjmp%2Flinux-2.6

diff --git a/include/linux/nsproxy.h b/include/linux/nsproxy.h
index 9c2e0ad..7b370c7 100644
--- a/include/linux/nsproxy.h
+++ b/include/linux/nsproxy.h
@@ -4,8 +4,11 @@
 #include <linux/spinlock.h>
 #include <linux/sched.h>
 
-struct namespace;
+struct mnt_namespace;
 struct uts_namespace;
+struct ipc_namespace;
+struct pid_namespace;
+struct fs_struct;
 
 /*
  * A structure to contain pointers to all per-process
@@ -21,16 +24,50 @@ struct uts_namespace;
  */
 struct nsproxy {
 	atomic_t count;
-	spinlock_t nslock;
 	struct uts_namespace *uts_ns;
-	struct namespace *namespace;
+	struct ipc_namespace *ipc_ns;
+	struct mnt_namespace *mnt_ns;
+	struct pid_namespace *pid_ns;
+	struct net 	     *net_ns;
 };
 extern struct nsproxy init_nsproxy;
 
-struct nsproxy *dup_namespaces(struct nsproxy *orig);
-int copy_namespaces(int flags, struct task_struct *tsk);
-void get_task_namespaces(struct task_struct *tsk);
+/*
+ * the namespaces access rules are:
+ *
+ *  1. only current task is allowed to change tsk->nsproxy pointer or
+ *     any pointer on the nsproxy itself
+ *
+ *  2. when accessing (i.e. reading) current task's namespaces - no
+ *     precautions should be taken - just dereference the pointers
+ *
+ *  3. the access to other task namespaces is performed like this
+ *     rcu_read_lock();
+ *     nsproxy = task_nsproxy(tsk);
+ *     if (nsproxy != NULL) {
+ *             / *
+ *               * work with the namespaces here
+ *               * e.g. get the reference on one of them
+ *               * /
+ *     } / *
+ *         * NULL task_nsproxy() means that this task is
+ *         * almost dead (zombie)
+ *         * /
+ *     rcu_read_unlock();
+ *
+ */
+
+static inline struct nsproxy *task_nsproxy(struct task_struct *tsk)
+{
+	return rcu_dereference(tsk->nsproxy);
+}
+
+int copy_namespaces(unsigned long flags, struct task_struct *tsk);
+void exit_task_namespaces(struct task_struct *tsk);
+void switch_task_namespaces(struct task_struct *tsk, struct nsproxy *new);
 void free_nsproxy(struct nsproxy *ns);
+int unshare_nsproxy_namespaces(unsigned long, struct nsproxy **,
+	struct fs_struct *);
 
 static inline void put_nsproxy(struct nsproxy *ns)
 {
@@ -39,12 +76,18 @@ static inline void put_nsproxy(struct nsproxy *ns)
 	}
 }
 
-static inline void exit_task_namespaces(struct task_struct *p)
+static inline void get_nsproxy(struct nsproxy *ns)
 {
-	struct nsproxy *ns = p->nsproxy;
-	if (ns) {
-		put_nsproxy(ns);
-		p->nsproxy = NULL;
-	}
+	atomic_inc(&ns->count);
+}
+
+#ifdef CONFIG_CGROUP_NS
+int ns_cgroup_clone(struct task_struct *tsk, struct pid *pid);
+#else
+static inline int ns_cgroup_clone(struct task_struct *tsk, struct pid *pid)
+{
+	return 0;
 }
 #endif
+
+#endif