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         struct dentry *proc_thread_self;
  37 #endif
  38 #ifdef CONFIG_BSD_PROCESS_ACCT
  39         struct bsd_acct_struct *bacct;
  40 #endif
  41         struct user_namespace *user_ns;
  42         struct work_struct proc_work;
  43         kgid_t pid_gid;
  44         int hide_pid;
  45         int reboot;     /* group exit code if this pidns was rebooted */
  46         unsigned int proc_inum;
  47 };
  48
  49 extern struct pid_namespace init_pid_ns;
  50
  51 #define PIDNS_HASH_ADDING (1U << 31)
  52
  53 #ifdef CONFIG_PID_NS
  54 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  55 {
  56         if (ns != &init_pid_ns)
  57                 kref_get(&ns->kref);
  58         return ns;
  59 }
  60
  61 extern struct pid_namespace *copy_pid_ns(unsigned long flags,
  62         struct user_namespace *user_ns, struct pid_namespace *ns);
  63 extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
  64 extern int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd);
  65 extern void put_pid_ns(struct pid_namespace *ns);
  66
  67 #else /* !CONFIG_PID_NS */
  68 #include <linux/err.h>
  69
  70 static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
  71 {
  72         return ns;
  73 }
  74
  75 static inline struct pid_namespace *copy_pid_ns(unsigned long flags,
  76         struct user_namespace *user_ns, struct pid_namespace *ns)
  77 {
  78         if (flags & CLONE_NEWPID)
  79                 ns = ERR_PTR(-EINVAL);
  80         return ns;
  81 }
  82
  83 static inline void put_pid_ns(struct pid_namespace *ns)
  84 {
  85 }
  86
  87 static inline void zap_pid_ns_processes(struct pid_namespace *ns)
  88 {
  89         BUG();
  90 }
  91
  92 static inline int reboot_pid_ns(struct pid_namespace *pid_ns, int cmd)
  93 {
  94         return 0;
  95 }
  96 #endif /* CONFIG_PID_NS */
  97
  98 extern struct pid_namespace *task_active_pid_ns(struct task_struct *tsk);
  99 void pidhash_init(void);
 100 void pidmap_init(void);
 101
 102 #endif /* _LINUX_PID_NS_H */