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