Merge branch 'mini2440-dev-unlikely' into mini2440-dev
[linux-2.6/mini2440.git] / include / linux / mount.h
blob5d5275364867879626d30b4511a7f064a635747f
1 /*
3 * Definitions for mount interface. This describes the in the kernel build
4 * linkedlist with mounted filesystems.
6 * Author: Marco van Wieringen <mvw@planets.elm.net>
8 */
9 #ifndef _LINUX_MOUNT_H
10 #define _LINUX_MOUNT_H
12 #include <linux/types.h>
13 #include <linux/list.h>
14 #include <linux/nodemask.h>
15 #include <linux/spinlock.h>
16 #include <asm/atomic.h>
18 struct super_block;
19 struct vfsmount;
20 struct dentry;
21 struct mnt_namespace;
23 #define MNT_NOSUID 0x01
24 #define MNT_NODEV 0x02
25 #define MNT_NOEXEC 0x04
26 #define MNT_NOATIME 0x08
27 #define MNT_NODIRATIME 0x10
28 #define MNT_RELATIME 0x20
29 #define MNT_READONLY 0x40 /* does the user want this to be r/o? */
30 #define MNT_STRICTATIME 0x80
32 #define MNT_SHRINKABLE 0x100
33 #define MNT_WRITE_HOLD 0x200
35 #define MNT_SHARED 0x1000 /* if the vfsmount is a shared mount */
36 #define MNT_UNBINDABLE 0x2000 /* if the vfsmount is a unbindable mount */
37 #define MNT_PNODE_MASK 0x3000 /* propagation flag mask */
39 struct vfsmount {
40 struct list_head mnt_hash;
41 struct vfsmount *mnt_parent; /* fs we are mounted on */
42 struct dentry *mnt_mountpoint; /* dentry of mountpoint */
43 struct dentry *mnt_root; /* root of the mounted tree */
44 struct super_block *mnt_sb; /* pointer to superblock */
45 struct list_head mnt_mounts; /* list of children, anchored here */
46 struct list_head mnt_child; /* and going through their mnt_child */
47 int mnt_flags;
48 /* 4 bytes hole on 64bits arches */
49 const char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */
50 struct list_head mnt_list;
51 struct list_head mnt_expire; /* link in fs-specific expiry list */
52 struct list_head mnt_share; /* circular list of shared mounts */
53 struct list_head mnt_slave_list;/* list of slave mounts */
54 struct list_head mnt_slave; /* slave list entry */
55 struct vfsmount *mnt_master; /* slave is on master->mnt_slave_list */
56 struct mnt_namespace *mnt_ns; /* containing namespace */
57 int mnt_id; /* mount identifier */
58 int mnt_group_id; /* peer group identifier */
60 * We put mnt_count & mnt_expiry_mark at the end of struct vfsmount
61 * to let these frequently modified fields in a separate cache line
62 * (so that reads of mnt_flags wont ping-pong on SMP machines)
64 atomic_t mnt_count;
65 int mnt_expiry_mark; /* true if marked for expiry */
66 int mnt_pinned;
67 int mnt_ghosts;
68 #ifdef CONFIG_SMP
69 int *mnt_writers;
70 #else
71 int mnt_writers;
72 #endif
75 static inline int *get_mnt_writers_ptr(struct vfsmount *mnt)
77 #ifdef CONFIG_SMP
78 return mnt->mnt_writers;
79 #else
80 return &mnt->mnt_writers;
81 #endif
84 static inline struct vfsmount *mntget(struct vfsmount *mnt)
86 if (mnt)
87 atomic_inc(&mnt->mnt_count);
88 return mnt;
91 struct file; /* forward dec */
93 extern int mnt_want_write(struct vfsmount *mnt);
94 extern int mnt_want_write_file(struct file *file);
95 extern int mnt_clone_write(struct vfsmount *mnt);
96 extern void mnt_drop_write(struct vfsmount *mnt);
97 extern void mntput_no_expire(struct vfsmount *mnt);
98 extern void mnt_pin(struct vfsmount *mnt);
99 extern void mnt_unpin(struct vfsmount *mnt);
100 extern int __mnt_is_readonly(struct vfsmount *mnt);
102 static inline void mntput(struct vfsmount *mnt)
104 if (mnt) {
105 mnt->mnt_expiry_mark = 0;
106 mntput_no_expire(mnt);
110 extern struct vfsmount *do_kern_mount(const char *fstype, int flags,
111 const char *name, void *data);
113 struct file_system_type;
114 extern struct vfsmount *vfs_kern_mount(struct file_system_type *type,
115 int flags, const char *name,
116 void *data);
118 struct nameidata;
120 struct path;
121 extern int do_add_mount(struct vfsmount *newmnt, struct path *path,
122 int mnt_flags, struct list_head *fslist);
124 extern void mark_mounts_for_expiry(struct list_head *mounts);
126 extern spinlock_t vfsmount_lock;
127 extern dev_t name_to_dev_t(char *name);
129 #endif /* _LINUX_MOUNT_H */