Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1#ifndef _LINUX_PID_NS_H
2#define _LINUX_PID_NS_H
3
4#include <linux/sched.h>
5#include <linux/mm.h>
6#include <linux/threads.h>
7#include <linux/nsproxy.h>
8#include <linux/kref.h>
9
10struct pidmap {
11 atomic_t nr_free;
12 void *page;
13};
14
15#define PIDMAP_ENTRIES ((PID_MAX_LIMIT + 8*PAGE_SIZE - 1)/PAGE_SIZE/8)
16
17struct pid_namespace {
18 struct kref kref;
19 struct pidmap pidmap[PIDMAP_ENTRIES];
20 int last_pid;
21 struct task_struct *child_reaper;
22 struct kmem_cache *pid_cachep;
23 int level;
24 struct pid_namespace *parent;
25#ifdef CONFIG_PROC_FS
26 struct vfsmount *proc_mnt;
27#endif
28};
29
30extern struct pid_namespace init_pid_ns;
31
32#ifdef CONFIG_PID_NS
33static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
34{
35 if (ns != &init_pid_ns)
36 kref_get(&ns->kref);
37 return ns;
38}
39
40extern struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *ns);
41extern void free_pid_ns(struct kref *kref);
42
43static inline void put_pid_ns(struct pid_namespace *ns)
44{
45 if (ns != &init_pid_ns)
46 kref_put(&ns->kref, free_pid_ns);
47}
48
49#else /* !CONFIG_PID_NS */
50#include <linux/err.h>
51
52static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
53{
54 return ns;
55}
56
57static inline struct pid_namespace *
58copy_pid_ns(unsigned long flags, struct pid_namespace *ns)
59{
60 if (flags & CLONE_NEWPID)
61 ns = ERR_PTR(-EINVAL);
62 return ns;
63}
64
65static inline void put_pid_ns(struct pid_namespace *ns)
66{
67}
68
69#endif /* CONFIG_PID_NS */
70
71static inline struct pid_namespace *task_active_pid_ns(struct task_struct *tsk)
72{
73 return tsk->nsproxy->pid_ns;
74}
75
76static inline struct task_struct *task_child_reaper(struct task_struct *tsk)
77{
78 BUG_ON(tsk != current);
79 return tsk->nsproxy->pid_ns->child_reaper;
80}
81
82#endif /* _LINUX_PID_NS_H */