include/linux/mount.h

   1 /*
   2  *
   3  * Definitions for mount interface. This describes the in the kernel build
   4  * linkedlist with mounted filesystems.
   5  *
   6  * Author:  Marco van Wieringen <mvw@planets.elm.net>
   7  *
   8  * Version: $Id: mount.h,v 2.0 1996/11/17 16:48:14 mvw Exp mvw $
   9  *
  10  */
  11 #ifndef _LINUX_MOUNT_H
  12 #define _LINUX_MOUNT_H
  13 #ifdef __KERNEL__
  14
  15 #define MNT_VISIBLE     1
  16
  17 struct vfsmount
  18 {
  19         struct dentry *mnt_mountpoint;  /* dentry of mountpoint */
  20         struct dentry *mnt_root;        /* root of the mounted tree */
  21         struct vfsmount *mnt_parent;    /* fs we are mounted on */
  22         struct list_head mnt_instances; /* other vfsmounts of the same fs */
  23         struct list_head mnt_clash;     /* those who are mounted on (other */
  24                                         /* instances) of the same dentry */
  25         struct super_block *mnt_sb;     /* pointer to superblock */
  26         struct list_head mnt_mounts;    /* list of children, anchored here */
  27         struct list_head mnt_child;     /* and going through their mnt_child */
  28         atomic_t mnt_count;
  29         int mnt_flags;
  30         char *mnt_devname;              /* Name of device e.g. /dev/dsk/hda1 */
  31         struct list_head mnt_list;
  32         uid_t mnt_owner;
  33 };
  34
  35 static inline struct vfsmount *mntget(struct vfsmount *mnt)
  36 {
  37         if (mnt)
  38                 atomic_inc(&mnt->mnt_count);
  39         return mnt;
  40 }
  41
  42 static inline void mntput(struct vfsmount *mnt)
  43 {
  44         if (mnt) {
  45                 if (atomic_dec_and_test(&mnt->mnt_count))
  46                         BUG();
  47         }
  48 }
  49
  50 #endif
  51 #endif /* _LINUX_MOUNT_H */