1 /* SPDX-License-Identifier: GPL-2.0 */
2 #include <linux/mount.h>
3 #include <linux/seq_file.h>
4 #include <linux/poll.h>
5 #include <linux/ns_common.h>
6 #include <linux/fs_pin.h>
12 struct list_head list;
13 struct user_namespace *user_ns;
14 struct ucounts *ucounts;
15 u64 seq; /* Sequence number to prevent loops */
16 wait_queue_head_t poll;
18 unsigned int mounts; /* # of mounts in the namespace */
19 unsigned int pending_mounts;
28 struct hlist_node m_hash;
29 struct dentry *m_dentry;
30 struct hlist_head m_list;
35 struct hlist_node mnt_hash;
36 struct mount *mnt_parent;
37 struct dentry *mnt_mountpoint;
40 struct rcu_head mnt_rcu;
41 struct llist_node mnt_llist;
44 struct mnt_pcp __percpu *mnt_pcp;
49 struct list_head mnt_mounts; /* list of children, anchored here */
50 struct list_head mnt_child; /* and going through their mnt_child */
51 struct list_head mnt_instance; /* mount instance on sb->s_mounts */
52 const char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */
53 struct list_head mnt_list;
54 struct list_head mnt_expire; /* link in fs-specific expiry list */
55 struct list_head mnt_share; /* circular list of shared mounts */
56 struct list_head mnt_slave_list;/* list of slave mounts */
57 struct list_head mnt_slave; /* slave list entry */
58 struct mount *mnt_master; /* slave is on master->mnt_slave_list */
59 struct mnt_namespace *mnt_ns; /* containing namespace */
60 struct mountpoint *mnt_mp; /* where is it mounted */
61 struct hlist_node mnt_mp_list; /* list mounts with the same mountpoint */
62 struct list_head mnt_umounting; /* list entry for umount propagation */
63 #ifdef CONFIG_FSNOTIFY
64 struct fsnotify_mark_connector __rcu *mnt_fsnotify_marks;
65 __u32 mnt_fsnotify_mask;
67 int mnt_id; /* mount identifier */
68 int mnt_group_id; /* peer group identifier */
69 int mnt_expiry_mark; /* true if marked for expiry */
70 struct hlist_head mnt_pins;
71 struct fs_pin mnt_umount;
74 #define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */
76 static inline struct mount *real_mount(struct vfsmount *mnt)
78 return container_of(mnt, struct mount, mnt);
81 static inline int mnt_has_parent(struct mount *mnt)
83 return mnt != mnt->mnt_parent;
86 static inline int is_mounted(struct vfsmount *mnt)
88 /* neither detached nor internal? */
89 return !IS_ERR_OR_NULL(real_mount(mnt)->mnt_ns);
92 extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *);
94 extern int __legitimize_mnt(struct vfsmount *, unsigned);
95 extern bool legitimize_mnt(struct vfsmount *, unsigned);
97 static inline bool __path_is_mountpoint(const struct path *path)
99 struct mount *m = __lookup_mnt(path->mnt, path->dentry);
100 return m && likely(!(m->mnt.mnt_flags & MNT_SYNC_UMOUNT));
103 extern void __detach_mounts(struct dentry *dentry);
105 static inline void detach_mounts(struct dentry *dentry)
107 if (!d_mountpoint(dentry))
109 __detach_mounts(dentry);
112 static inline void get_mnt_ns(struct mnt_namespace *ns)
114 atomic_inc(&ns->count);
117 extern seqlock_t mount_lock;
119 static inline void lock_mount_hash(void)
121 write_seqlock(&mount_lock);
124 static inline void unlock_mount_hash(void)
126 write_sequnlock(&mount_lock);
130 struct mnt_namespace *ns;
132 int (*show)(struct seq_file *, struct vfsmount *);
138 extern const struct seq_operations mounts_op;
140 extern bool __is_local_mountpoint(struct dentry *dentry);
141 static inline bool is_local_mountpoint(struct dentry *dentry)
143 if (!d_mountpoint(dentry))
146 return __is_local_mountpoint(dentry);
149 static inline bool is_anon_ns(struct mnt_namespace *ns)