LXR linux/include/linux/pid

   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);
  42extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
  43
  44static inline void put_pid_ns(struct pid_namespace *ns)
  45{
  46        if (ns != &init_pid_ns)
  47                kref_put(&ns->kref, free_pid_ns);
  48}
  49
  50#else /* !CONFIG_PID_NS */
  51#include <linux/err.h>
  52
  53static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  54{
  55        return ns;
  56}
  57
  58static inline struct pid_namespace *
  59copy_pid_ns(unsigned long flags, struct pid_namespace *ns)
  60{
  61        if (flags & CLONE_NEWPID)
  62                ns = ERR_PTR(-EINVAL);
  63        return ns;
  64}
  65
  66static inline void put_pid_ns(struct pid_namespace *ns)
  67{
  68}
  69
  70
  71static inline void zap_pid_ns_processes(struct pid_namespace *ns)
  72{
  73        BUG();
  74}
  75#endif /* CONFIG_PID_NS */
  76
  77static inline struct pid_namespace *task_active_pid_ns(struct task_struct *tsk)
  78{
  79        return tsk->nsproxy->pid_ns;
  80}
  81
  82static inline struct task_struct *task_child_reaper(struct task_struct *tsk)
  83{
  84        BUG_ON(tsk != current);
  85        return tsk->nsproxy->pid_ns->child_reaper;
  86}
  87
  88#endif /* _LINUX_PID_NS_H */
  89