1 #ifndef _LINUX_PID_NS_H
2 #define _LINUX_PID_NS_H
3 
4 #include <linux/sched.h>
5 #include <linux/bug.h>
6 #include <linux/mm.h>
7 #include <linux/workqueue.h>
8 #include <linux/threads.h>
9 #include <linux/nsproxy.h>
10 #include <linux/kref.h>
11 #include <linux/ns_common.h>
12 
13 struct pidmap {
14        atomic_t nr_free;
15        void *page;
16 };
17 
18 #define BITS_PER_PAGE		(PAGE_SIZE * 8)
19 #define BITS_PER_PAGE_MASK	(BITS_PER_PAGE-1)
20 #define PIDMAP_ENTRIES		((PID_MAX_LIMIT+BITS_PER_PAGE-1)/BITS_PER_PAGE)
21 
22 struct fs_pin;
23 
24 struct pid_namespace {
25 	struct kref kref;
26 	struct pidmap pidmap[PIDMAP_ENTRIES];
27 	struct rcu_head rcu;
28 	int last_pid;
29 	unsigned int nr_hashed;
30 	struct task_struct *child_reaper;
31 	struct kmem_cache *pid_cachep;
32 	unsigned int level;
33 	struct pid_namespace *parent;
34 #ifdef CONFIG_PROC_FS
35 	struct vfsmount *proc_mnt;
36 	struct dentry *proc_self;
37 	struct dentry *proc_thread_self;
38 #endif
39 #ifdef CONFIG_BSD_PROCESS_ACCT
40 	struct fs_pin *bacct;
41 #endif
42 	struct user_namespace *user_ns;
43 	struct work_struct proc_work;
44 	kgid_t pid_gid;
45 	int hide_pid;
46 	int reboot;	/* group exit code if this pidns was rebooted */
47 	struct ns_common ns;
48 };
49 
50 extern struct pid_namespace init_pid_ns;
51 
52 #define PIDNS_HASH_ADDING (1U << 31)
53 
54 #ifdef CONFIG_PID_NS
get_pid_ns(struct pid_namespace * ns)55 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
56 {
57 	if (ns != &init_pid_ns)
58 		kref_get(&ns->kref);
59 	return ns;
60 }
61 
62 extern struct pid_namespace *copy_pid_ns(unsigned long flags,
63 	struct user_namespace *user_ns, struct pid_namespace *ns);
64 extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
65 extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd);
66 extern void put_pid_ns(struct pid_namespace *ns);
67 
68 #else /* !CONFIG_PID_NS */
69 #include <linux/err.h>
70 
get_pid_ns(struct pid_namespace * ns)71 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
72 {
73 	return ns;
74 }
75 
copy_pid_ns(unsigned long flags,struct user_namespace * user_ns,struct pid_namespace * ns)76 static inline struct pid_namespace *copy_pid_ns(unsigned long flags,
77 	struct user_namespace *user_ns, struct pid_namespace *ns)
78 {
79 	if (flags & CLONE_NEWPID)
80 		ns = ERR_PTR(-EINVAL);
81 	return ns;
82 }
83 
put_pid_ns(struct pid_namespace * ns)84 static inline void put_pid_ns(struct pid_namespace *ns)
85 {
86 }
87 
zap_pid_ns_processes(struct pid_namespace * ns)88 static inline void zap_pid_ns_processes(struct pid_namespace *ns)
89 {
90 	BUG();
91 }
92 
reboot_pid_ns(struct pid_namespace * pid_ns,int cmd)93 static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
94 {
95 	return 0;
96 }
97 #endif /* CONFIG_PID_NS */
98 
99 extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
100 void pidhash_init(void);
101 void pidmap_init(void);
102 
103 #endif /* _LINUX_PID_NS_H */
104