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 BITS_PER_PAGE           (PAGE_SIZE * 8)
  17 #define BITS_PER_PAGE_MASK      (BITS_PER_PAGE-1)
  18 #define PIDMAP_ENTRIES          ((PID_MAX_LIMIT+BITS_PER_PAGE-1)/BITS_PER_PAGE)
  19
  20 struct bsd_acct_struct;
  21
  22 struct pid_namespace {
  23         struct kref kref;
  24         struct pidmap pidmap[PIDMAP_ENTRIES];
  25         int last_pid;
  26         unsigned int nr_hashed;
  27         struct task_struct *child_reaper;
  28         struct kmem_cache *pid_cachep;
  29         unsigned int level;
  30         struct pid_namespace *parent;
  31 #ifdef CONFIG_PROC_FS
  32         struct vfsmount *proc_mnt;
  33         struct dentry *proc_self;
  34 #endif
  35 #ifdef CONFIG_BSD_PROCESS_ACCT
  36         struct bsd_acct_struct *bacct;
  37 #endif
  38         struct user_namespace *user_ns;
  39         struct work_struct proc_work;
  40         kgid_t pid_gid;
  41         int hide_pid;
  42         int reboot;     /* group exit code if this pidns was rebooted */
  43         unsigned int proc_inum;
  44 };
  45
  46 extern struct pid_namespace init_pid_ns;
  47
  48 #define PIDNS_HASH_ADDING (1U << 31)
  49
  50 #ifdef CONFIG_PID_NS
  51 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  52 {
  53         if (ns != &init_pid_ns)
  54                 kref_get(&ns->kref);
  55         return ns;
  56 }
  57
  58 extern struct pid_namespace *copy_pid_ns(unsigned long flags,
  59         struct user_namespace *user_ns, struct pid_namespace *ns);
  60 extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
  61 extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd);
  62 extern void put_pid_ns(struct pid_namespace *ns);
  63
  64 #else /* !CONFIG_PID_NS */
  65 #include <linux/err.h>
  66
  67 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  68 {
  69         return ns;
  70 }
  71
  72 static inline struct pid_namespace *copy_pid_ns(unsigned long flags,
  73         struct user_namespace *user_ns, struct pid_namespace *ns)
  74 {
  75         if (flags & CLONE_NEWPID)
  76                 ns = ERR_PTR(-EINVAL);
  77         return ns;
  78 }
  79
  80 static inline void put_pid_ns(struct pid_namespace *ns)
  81 {
  82 }
  83
  84 static inline void zap_pid_ns_processes(struct pid_namespace *ns)
  85 {
  86         BUG();
  87 }
  88
  89 static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
  90 {
  91         return 0;
  92 }
  93 #endif /* CONFIG_PID_NS */
  94
  95 extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
  96 void pidhash_init(void);
  97 void pidmap_init(void);
  98
  99 #endif /* _LINUX_PID_NS_H */