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