blob: a17458ca6f29e4dbf1f1a1b8bb9e97949b279d29 [file] [log] [blame]
Al Virob2dba1a2011-11-23 19:26:23 -05001#include <linux/mount.h>
Al Viro0226f492011-12-06 12:21:54 -05002#include <linux/seq_file.h>
3#include <linux/poll.h>
4
5struct mnt_namespace {
6 atomic_t count;
Eric W. Biederman98f842e2011-06-15 10:21:48 -07007 unsigned int proc_inum;
Al Virobe08d6d2011-12-06 13:32:36 -05008 struct mount * root;
Al Viro0226f492011-12-06 12:21:54 -05009 struct list_head list;
Eric W. Biederman771b1372012-07-26 21:08:32 -070010 struct user_namespace *user_ns;
Eric W. Biederman8823c072010-03-07 18:49:36 -080011 u64 seq; /* Sequence number to prevent loops */
Al Viro0226f492011-12-06 12:21:54 -050012 wait_queue_head_t poll;
13 int event;
14};
Al Virob2dba1a2011-11-23 19:26:23 -050015
Al Viro68e8a9f2011-11-24 22:53:09 -050016struct mnt_pcp {
17 int mnt_count;
18 int mnt_writers;
19};
20
Al Viro84d17192013-03-15 10:53:28 -040021struct mountpoint {
22 struct list_head m_hash;
23 struct dentry *m_dentry;
24 int m_count;
25};
26
Al Viro7d6fec42011-11-23 12:14:10 -050027struct mount {
Al Viro1b8e5562011-11-24 21:01:32 -050028 struct list_head mnt_hash;
Al Viro0714a532011-11-24 22:19:58 -050029 struct mount *mnt_parent;
Al Viroa73324d2011-11-24 22:25:07 -050030 struct dentry *mnt_mountpoint;
Al Viro7d6fec42011-11-23 12:14:10 -050031 struct vfsmount mnt;
Al Viro48a066e2013-09-29 22:06:07 -040032 struct rcu_head mnt_rcu;
Al Viro68e8a9f2011-11-24 22:53:09 -050033#ifdef CONFIG_SMP
34 struct mnt_pcp __percpu *mnt_pcp;
Al Viro68e8a9f2011-11-24 22:53:09 -050035#else
36 int mnt_count;
37 int mnt_writers;
38#endif
Al Viro6b41d532011-11-24 23:24:33 -050039 struct list_head mnt_mounts; /* list of children, anchored here */
40 struct list_head mnt_child; /* and going through their mnt_child */
Miklos Szeredi39f7c4d2011-11-21 12:11:30 +010041 struct list_head mnt_instance; /* mount instance on sb->s_mounts */
Al Viro52ba1622011-11-25 02:25:17 -050042 const char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */
Al Viro1a4eeaf2011-11-25 02:19:55 -050043 struct list_head mnt_list;
Al Viro6776db3d2011-11-25 00:22:05 -050044 struct list_head mnt_expire; /* link in fs-specific expiry list */
45 struct list_head mnt_share; /* circular list of shared mounts */
46 struct list_head mnt_slave_list;/* list of slave mounts */
47 struct list_head mnt_slave; /* slave list entry */
Al Viro32301922011-11-25 00:10:28 -050048 struct mount *mnt_master; /* slave is on master->mnt_slave_list */
Al Viro143c8c92011-11-25 00:46:35 -050049 struct mnt_namespace *mnt_ns; /* containing namespace */
Al Viro84d17192013-03-15 10:53:28 -040050 struct mountpoint *mnt_mp; /* where is it mounted */
Al Viroc63181e2011-11-25 02:35:16 -050051#ifdef CONFIG_FSNOTIFY
52 struct hlist_head mnt_fsnotify_marks;
53 __u32 mnt_fsnotify_mask;
54#endif
Al Viro15169fe2011-11-25 00:50:41 -050055 int mnt_id; /* mount identifier */
56 int mnt_group_id; /* peer group identifier */
Al Viro863d6842011-11-25 00:57:42 -050057 int mnt_expiry_mark; /* true if marked for expiry */
58 int mnt_pinned;
Al Viroaba809cf2013-09-28 23:10:55 -040059 struct path mnt_ex_mountpoint;
Al Viro7d6fec42011-11-23 12:14:10 -050060};
61
Al Virof7a99c52012-06-09 00:59:08 -040062#define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */
63
Al Viro7d6fec42011-11-23 12:14:10 -050064static inline struct mount *real_mount(struct vfsmount *mnt)
65{
66 return container_of(mnt, struct mount, mnt);
67}
68
Al Viro676da582011-11-24 21:47:05 -050069static inline int mnt_has_parent(struct mount *mnt)
Al Virob2dba1a2011-11-23 19:26:23 -050070{
Al Viro0714a532011-11-24 22:19:58 -050071 return mnt != mnt->mnt_parent;
Al Virob2dba1a2011-11-23 19:26:23 -050072}
Al Viroc7105362011-11-24 18:22:03 -050073
Al Virof7a99c52012-06-09 00:59:08 -040074static inline int is_mounted(struct vfsmount *mnt)
75{
76 /* neither detached nor internal? */
Eric W. Biederman260a4592014-01-20 15:26:15 -080077 return !IS_ERR_OR_NULL(real_mount(mnt)->mnt_ns);
Al Virof7a99c52012-06-09 00:59:08 -040078}
79
Al Viro474279d2013-10-01 16:11:26 -040080extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *);
81extern struct mount *__lookup_mnt_last(struct vfsmount *, struct dentry *);
Al Viro0226f492011-12-06 12:21:54 -050082
Al Viro48a066e2013-09-29 22:06:07 -040083extern bool legitimize_mnt(struct vfsmount *, unsigned);
84
Al Viro0226f492011-12-06 12:21:54 -050085static inline void get_mnt_ns(struct mnt_namespace *ns)
86{
87 atomic_inc(&ns->count);
88}
89
Al Viro48a066e2013-09-29 22:06:07 -040090extern seqlock_t mount_lock;
Al Viro719ea2f2013-09-29 11:24:49 -040091
92static inline void lock_mount_hash(void)
93{
Al Viro48a066e2013-09-29 22:06:07 -040094 write_seqlock(&mount_lock);
Al Viro719ea2f2013-09-29 11:24:49 -040095}
96
97static inline void unlock_mount_hash(void)
98{
Al Viro48a066e2013-09-29 22:06:07 -040099 write_sequnlock(&mount_lock);
Al Viro719ea2f2013-09-29 11:24:49 -0400100}
101
Al Viro0226f492011-12-06 12:21:54 -0500102struct proc_mounts {
Al Viro6ce6e242012-06-09 01:16:59 -0400103 struct seq_file m;
Al Viro0226f492011-12-06 12:21:54 -0500104 struct mnt_namespace *ns;
105 struct path root;
106 int (*show)(struct seq_file *, struct vfsmount *);
107};
108
Al Viro6ce6e242012-06-09 01:16:59 -0400109#define proc_mounts(p) (container_of((p), struct proc_mounts, m))
110
Al Viro0226f492011-12-06 12:21:54 -0500111extern const struct seq_operations mounts_op;