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/workqueue.h>
   8 #include <linux/threads.h>
   9 #include <linux/nsproxy.h>
  10 #include <linux/kref.h>
  11
  12 struct pidmap {
  13        atomic_t nr_free;
  14        void *page;
  15 };
  16
  17 #define BITS_PER_PAGE           (PAGE_SIZE * 8)
  18 #define BITS_PER_PAGE_MASK      (BITS_PER_PAGE-1)
  19 #define PIDMAP_ENTRIES          ((PID_MAX_LIMIT+BITS_PER_PAGE-1)/BITS_PER_PAGE)
  20
  21 struct bsd_acct_struct;
  22
  23 struct pid_namespace {
  24         struct kref kref;
  25         struct pidmap pidmap[PIDMAP_ENTRIES];
  26         struct rcu_head rcu;
  27         int last_pid;
  28         unsigned int nr_hashed;
  29         struct task_struct *child_reaper;
  30         struct kmem_cache *pid_cachep;
  31         unsigned int level;
  32         struct pid_namespace *parent;
  33 #ifdef CONFIG_PROC_FS
  34         struct vfsmount *proc_mnt;
  35         struct dentry *proc_self;
  36 #endif
  37 #ifdef CONFIG_BSD_PROCESS_ACCT
  38         struct bsd_acct_struct *bacct;
  39 #endif
  40         struct user_namespace *user_ns;
  41         struct work_struct proc_work;
  42         kgid_t pid_gid;
  43         int hide_pid;
  44         int reboot;     /* group exit code if this pidns was rebooted */
  45         unsigned int proc_inum;
  46 };
  47
  48 extern struct pid_namespace init_pid_ns;
  49
  50 #define PIDNS_HASH_ADDING (1U << 31)
  51
  52 #ifdef CONFIG_PID_NS
  53 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  54 {
  55         if (ns != &init_pid_ns)
  56                 kref_get(&ns->kref);
  57         return ns;
  58 }
  59
  60 extern struct pid_namespace *copy_pid_ns(unsigned long flags,
  61         struct user_namespace *user_ns, struct pid_namespace *ns);
  62 extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
  63 extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd);
  64 extern void put_pid_ns(struct pid_namespace *ns);
  65
  66 #else /* !CONFIG_PID_NS */
  67 #include <linux/err.h>
  68
  69 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  70 {
  71         return ns;
  72 }
  73
  74 static inline struct pid_namespace *copy_pid_ns(unsigned long flags,
  75         struct user_namespace *user_ns, struct pid_namespace *ns)
  76 {
  77         if (flags & CLONE_NEWPID)
  78                 ns = ERR_PTR(-EINVAL);
  79         return ns;
  80 }
  81
  82 static inline void put_pid_ns(struct pid_namespace *ns)
  83 {
  84 }
  85
  86 static inline void zap_pid_ns_processes(struct pid_namespace *ns)
  87 {
  88         BUG();
  89 }
  90
  91 static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
  92 {
  93         return 0;
  94 }
  95 #endif /* CONFIG_PID_NS */
  96
  97 extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
  98 void pidhash_init(void);
  99 void pidmap_init(void);
 100
 101 #endif /* _LINUX_PID_NS_H */