Blame view

include/linux/mount.h 3.37 KB
81f7e3824   Eric Lee   Initial Release, ...
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
  /* SPDX-License-Identifier: GPL-2.0 */
  /*
   *
   * Definitions for mount interface. This describes the in the kernel build 
   * linkedlist with mounted filesystems.
   *
   * Author:  Marco van Wieringen <mvw@planets.elm.net>
   *
   */
  #ifndef _LINUX_MOUNT_H
  #define _LINUX_MOUNT_H
  
  #include <linux/types.h>
  #include <linux/list.h>
  #include <linux/nodemask.h>
  #include <linux/spinlock.h>
  #include <linux/seqlock.h>
  #include <linux/atomic.h>
  
  struct super_block;
  struct vfsmount;
  struct dentry;
  struct mnt_namespace;
  
  #define MNT_NOSUID	0x01
  #define MNT_NODEV	0x02
  #define MNT_NOEXEC	0x04
  #define MNT_NOATIME	0x08
  #define MNT_NODIRATIME	0x10
  #define MNT_RELATIME	0x20
  #define MNT_READONLY	0x40	/* does the user want this to be r/o? */
  
  #define MNT_SHRINKABLE	0x100
  #define MNT_WRITE_HOLD	0x200
  
  #define MNT_SHARED	0x1000	/* if the vfsmount is a shared mount */
  #define MNT_UNBINDABLE	0x2000	/* if the vfsmount is a unbindable mount */
  /*
   * MNT_SHARED_MASK is the set of flags that should be cleared when a
   * mount becomes shared.  Currently, this is only the flag that says a
   * mount cannot be bind mounted, since this is how we create a mount
   * that shares events with another mount.  If you add a new MNT_*
   * flag, consider how it interacts with shared mounts.
   */
  #define MNT_SHARED_MASK	(MNT_UNBINDABLE)
  #define MNT_USER_SETTABLE_MASK  (MNT_NOSUID | MNT_NODEV | MNT_NOEXEC \
  				 | MNT_NOATIME | MNT_NODIRATIME | MNT_RELATIME \
  				 | MNT_READONLY)
  #define MNT_ATIME_MASK (MNT_NOATIME | MNT_NODIRATIME | MNT_RELATIME )
  
  #define MNT_INTERNAL_FLAGS (MNT_SHARED | MNT_WRITE_HOLD | MNT_INTERNAL | \
  			    MNT_DOOMED | MNT_SYNC_UMOUNT | MNT_MARKED)
  
  #define MNT_INTERNAL	0x4000
  
  #define MNT_LOCK_ATIME		0x040000
  #define MNT_LOCK_NOEXEC		0x080000
  #define MNT_LOCK_NOSUID		0x100000
  #define MNT_LOCK_NODEV		0x200000
  #define MNT_LOCK_READONLY	0x400000
  #define MNT_LOCKED		0x800000
  #define MNT_DOOMED		0x1000000
  #define MNT_SYNC_UMOUNT		0x2000000
  #define MNT_MARKED		0x4000000
  #define MNT_UMOUNT		0x8000000
  
  struct vfsmount {
  	struct dentry *mnt_root;	/* root of the mounted tree */
  	struct super_block *mnt_sb;	/* pointer to superblock */
  	int mnt_flags;
  	void *data;
  } __randomize_layout;
  
  struct file; /* forward dec */
  struct path;
  
  extern int mnt_want_write(struct vfsmount *mnt);
  extern int mnt_want_write_file(struct file *file);
  extern int mnt_clone_write(struct vfsmount *mnt);
  extern void mnt_drop_write(struct vfsmount *mnt);
  extern void mnt_drop_write_file(struct file *file);
  extern void mntput(struct vfsmount *mnt);
  extern struct vfsmount *mntget(struct vfsmount *mnt);
  extern struct vfsmount *mnt_clone_internal(const struct path *path);
  extern int __mnt_is_readonly(struct vfsmount *mnt);
  extern bool mnt_may_suid(struct vfsmount *mnt);
  
  struct path;
  extern struct vfsmount *clone_private_mount(const struct path *path);
  
  struct file_system_type;
  extern struct vfsmount *vfs_kern_mount(struct file_system_type *type,
  				      int flags, const char *name,
  				      void *data);
  extern struct vfsmount *vfs_submount(const struct dentry *mountpoint,
  				     struct file_system_type *type,
  				     const char *name, void *data);
  
  extern void mnt_set_expiry(struct vfsmount *mnt, struct list_head *expiry_list);
  extern void mark_mounts_for_expiry(struct list_head *mounts);
  
  extern dev_t name_to_dev_t(const char *name);
  
  extern unsigned int sysctl_mount_max;
  
  extern bool path_is_mountpoint(const struct path *path);
  
  #endif /* _LINUX_MOUNT_H */