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/mm.h>
   6 #include <linux/threads.h>
   7 #include <linux/nsproxy.h>
   8 #include <linux/kref.h>
   9
  10 struct 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
  17 struct bsd_acct_struct;
  18
  19 struct pid_namespace {
  20         struct kref kref;
  21         struct pidmap pidmap[PIDMAP_ENTRIES];
  22         int last_pid;
  23         struct task_struct *child_reaper;
  24         struct kmem_cache *pid_cachep;
  25         unsigned int level;
  26         struct pid_namespace *parent;
  27 #ifdef CONFIG_PROC_FS
  28         struct vfsmount *proc_mnt;
  29 #endif
  30 #ifdef CONFIG_BSD_PROCESS_ACCT
  31         struct bsd_acct_struct *bacct;
  32 #endif
  33         gid_t pid_gid;
  34         int hide_pid;
  35 };
  36
  37 extern struct pid_namespace init_pid_ns;
  38
  39 #ifdef CONFIG_PID_NS
  40 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  41 {
  42         if (ns != &init_pid_ns)
  43                 kref_get(&ns->kref);
  44         return ns;
  45 }
  46
  47 extern struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *ns);
  48 extern void free_pid_ns(struct kref *kref);
  49 extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
  50
  51 static inline void put_pid_ns(struct pid_namespace *ns)
  52 {
  53         if (ns != &init_pid_ns)
  54                 kref_put(&ns->kref, free_pid_ns);
  55 }
  56
  57 #else /* !CONFIG_PID_NS */
  58 #include <linux/err.h>
  59
  60 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  61 {
  62         return ns;
  63 }
  64
  65 static inline struct pid_namespace *
  66 copy_pid_ns(unsigned long flags, struct pid_namespace *ns)
  67 {
  68         if (flags & CLONE_NEWPID)
  69                 ns = ERR_PTR(-EINVAL);
  70         return ns;
  71 }
  72
  73 static inline void put_pid_ns(struct pid_namespace *ns)
  74 {
  75 }
  76
  77
  78 static inline void zap_pid_ns_processes(struct pid_namespace *ns)
  79 {
  80         BUG();
  81 }
  82 #endif /* CONFIG_PID_NS */
  83
  84 extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
  85 void pidhash_init(void);
  86 void pidmap_init(void);
  87
  88 #endif /* _LINUX_PID_NS_H */