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         struct task_struct *child_reaper;
  25         struct kmem_cache *pid_cachep;
  26         unsigned int level;
  27         struct pid_namespace *parent;
  28 #ifdef CONFIG_PROC_FS
  29         struct vfsmount *proc_mnt;
  30 #endif
  31 #ifdef CONFIG_BSD_PROCESS_ACCT
  32         struct bsd_acct_struct *bacct;
  33 #endif
  34         kgid_t pid_gid;
  35         int hide_pid;
  36         int reboot;     /* group exit code if this pidns was rebooted */
  37 };
  38
  39 extern struct pid_namespace init_pid_ns;
  40
  41 #ifdef CONFIG_PID_NS
  42 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  43 {
  44         if (ns != &init_pid_ns)
  45                 kref_get(&ns->kref);
  46         return ns;
  47 }
  48
  49 extern struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *ns);
  50 extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
  51 extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd);
  52 extern void put_pid_ns(struct pid_namespace *ns);
  53
  54 #else /* !CONFIG_PID_NS */
  55 #include <linux/err.h>
  56
  57 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  58 {
  59         return ns;
  60 }
  61
  62 static inline struct pid_namespace *
  63 copy_pid_ns(unsigned long flags, struct pid_namespace *ns)
  64 {
  65         if (flags & CLONE_NEWPID)
  66                 ns = ERR_PTR(-EINVAL);
  67         return ns;
  68 }
  69
  70 static inline void put_pid_ns(struct pid_namespace *ns)
  71 {
  72 }
  73
  74 static inline void zap_pid_ns_processes(struct pid_namespace *ns)
  75 {
  76         BUG();
  77 }
  78
  79 static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
  80 {
  81         return 0;
  82 }
  83 #endif /* CONFIG_PID_NS */
  84
  85 extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
  86 void pidhash_init(void);
  87 void pidmap_init(void);
  88
  89 #endif /* _LINUX_PID_NS_H */