include/linux/namespace.h

   1 #ifndef _NAMESPACE_H_
   2 #define _NAMESPACE_H_
   3 #ifdef __KERNEL__
   4
   5 #include <linux/mount.h>
   6 #include <linux/sched.h>
   7
   8 struct namespace {
   9         atomic_t                count;
  10         struct vfsmount *       root;
  11         struct list_head        list;
  12         struct rw_semaphore     sem;
  13 };
  14
  15 extern int copy_namespace(int, struct task_struct *);
  16 extern void __put_namespace(struct namespace *namespace);
  17
  18 static inline void put_namespace(struct namespace *namespace)
  19 {
  20         if (atomic_dec_and_lock(&namespace->count, &vfsmount_lock))
  21                 /* releases vfsmount_lock */
  22                 __put_namespace(namespace);
  23 }
  24
  25 static inline void exit_namespace(struct task_struct *p)
  26 {
  27         struct namespace *namespace = p->namespace;
  28         if (namespace) {
  29                 task_lock(p);
  30                 p->namespace = NULL;
  31                 task_unlock(p);
  32                 put_namespace(namespace);
  33         }
  34 }
  35
  36 static inline void get_namespace(struct namespace *namespace)
  37 {
  38         atomic_inc(&namespace->count);
  39 }
  40
  41 #endif
  42 #endif