include/linux/mnt_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 #include <linux/nsproxy.h>
   8
   9 struct mnt_namespace {
  10         atomic_t                count;
  11         struct vfsmount *       root;
  12         struct list_head        list;
  13         wait_queue_head_t poll;
  14         int event;
  15 };
  16
  17 extern int copy_mnt_ns(int, struct task_struct *);
  18 extern void __put_mnt_ns(struct mnt_namespace *ns);
  19 extern struct mnt_namespace *dup_mnt_ns(struct task_struct *,
  20                 struct fs_struct *);
  21
  22 static inline void put_mnt_ns(struct mnt_namespace *ns)
  23 {
  24         if (atomic_dec_and_lock(&ns->count, &vfsmount_lock))
  25                 /* releases vfsmount_lock */
  26                 __put_mnt_ns(ns);
  27 }
  28
  29 static inline void exit_mnt_ns(struct task_struct *p)
  30 {
  31         struct mnt_namespace *ns = p->nsproxy->mnt_ns;
  32         if (ns)
  33                 put_mnt_ns(ns);
  34 }
  35
  36 static inline void get_mnt_ns(struct mnt_namespace *ns)
  37 {
  38         atomic_inc(&ns->count);
  39 }
  40
  41 #endif
  42 #endif