include/linux/pid_namespace.h

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