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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>
Al Viro435d5f42014-10-31 22:56:04 -04004#include <linux/ns_common.h>
Al Viro0226f492011-12-06 12:21:54 -05005
6struct mnt_namespace {
7 atomic_t count;
Al Viro435d5f42014-10-31 22:56:04 -04008 struct ns_common ns;
Al Virobe08d6d2011-12-06 13:32:36 -05009 struct mount * root;
Al Viro0226f492011-12-06 12:21:54 -050010 struct list_head list;
Eric W. Biederman771b1372012-07-26 21:08:32 -070011 struct user_namespace *user_ns;
Eric W. Biederman8823c072010-03-07 18:49:36 -080012 u64 seq; /* Sequence number to prevent loops */
Al Viro0226f492011-12-06 12:21:54 -050013 wait_queue_head_t poll;
Al Viroc7999c32014-02-27 14:40:10 -050014 u64 event;
Al Viro0226f492011-12-06 12:21:54 -050015};
Al Virob2dba1a2011-11-23 19:26:23 -050016
Al Viro68e8a9f2011-11-24 22:53:09 -050017struct mnt_pcp {
18 int mnt_count;
19 int mnt_writers;
20};
21
Al Viro84d17192013-03-15 10:53:28 -040022struct mountpoint {
Al Viro0818bf22014-02-28 13:46:44 -050023 struct hlist_node m_hash;
Al Viro84d17192013-03-15 10:53:28 -040024 struct dentry *m_dentry;
Eric W. Biederman0a5eb7c2013-09-22 19:37:01 -070025 struct hlist_head m_list;
Al Viro84d17192013-03-15 10:53:28 -040026 int m_count;
27};
28
Al Viro7d6fec42011-11-23 12:14:10 -050029struct mount {
Al Viro38129a12014-03-20 21:10:51 -040030 struct hlist_node mnt_hash;
Al Viro0714a532011-11-24 22:19:58 -050031 struct mount *mnt_parent;
Al Viroa73324d2011-11-24 22:25:07 -050032 struct dentry *mnt_mountpoint;
Al Viro7d6fec42011-11-23 12:14:10 -050033 struct vfsmount mnt;
Al Viro9ea459e2014-08-08 13:08:20 -040034 union {
35 struct rcu_head mnt_rcu;
36 struct llist_node mnt_llist;
37 };
Al Viro68e8a9f2011-11-24 22:53:09 -050038#ifdef CONFIG_SMP
39 struct mnt_pcp __percpu *mnt_pcp;
Al Viro68e8a9f2011-11-24 22:53:09 -050040#else
41 int mnt_count;
42 int mnt_writers;
43#endif
Al Viro6b41d532011-11-24 23:24:33 -050044 struct list_head mnt_mounts; /* list of children, anchored here */
45 struct list_head mnt_child; /* and going through their mnt_child */
Miklos Szeredi39f7c4d2011-11-21 12:11:30 +010046 struct list_head mnt_instance; /* mount instance on sb->s_mounts */
Al Viro52ba1622011-11-25 02:25:17 -050047 const char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */
Al Viro1a4eeaf2011-11-25 02:19:55 -050048 struct list_head mnt_list;
Al Viro6776db3d2011-11-25 00:22:05 -050049 struct list_head mnt_expire; /* link in fs-specific expiry list */
50 struct list_head mnt_share; /* circular list of shared mounts */
51 struct list_head mnt_slave_list;/* list of slave mounts */
52 struct list_head mnt_slave; /* slave list entry */
Al Viro32301922011-11-25 00:10:28 -050053 struct mount *mnt_master; /* slave is on master->mnt_slave_list */
Al Viro143c8c92011-11-25 00:46:35 -050054 struct mnt_namespace *mnt_ns; /* containing namespace */
Al Viro84d17192013-03-15 10:53:28 -040055 struct mountpoint *mnt_mp; /* where is it mounted */
Eric W. Biederman0a5eb7c2013-09-22 19:37:01 -070056 struct hlist_node mnt_mp_list; /* list mounts with the same mountpoint */
Al Viroc63181e2011-11-25 02:35:16 -050057#ifdef CONFIG_FSNOTIFY
58 struct hlist_head mnt_fsnotify_marks;
59 __u32 mnt_fsnotify_mask;
60#endif
Al Viro15169fe2011-11-25 00:50:41 -050061 int mnt_id; /* mount identifier */
62 int mnt_group_id; /* peer group identifier */
Al Viro863d6842011-11-25 00:57:42 -050063 int mnt_expiry_mark; /* true if marked for expiry */
Al Viro215752f2014-08-07 06:23:41 -040064 struct hlist_head mnt_pins;
Al Viroaba809cf2013-09-28 23:10:55 -040065 struct path mnt_ex_mountpoint;
Al Viro7d6fec42011-11-23 12:14:10 -050066};
67
Al Virof7a99c52012-06-09 00:59:08 -040068#define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */
69
Al Viro7d6fec42011-11-23 12:14:10 -050070static inline struct mount *real_mount(struct vfsmount *mnt)
71{
72 return container_of(mnt, struct mount, mnt);
73}
74
Al Viro676da582011-11-24 21:47:05 -050075static inline int mnt_has_parent(struct mount *mnt)
Al Virob2dba1a2011-11-23 19:26:23 -050076{
Al Viro0714a532011-11-24 22:19:58 -050077 return mnt != mnt->mnt_parent;
Al Virob2dba1a2011-11-23 19:26:23 -050078}
Al Viroc7105362011-11-24 18:22:03 -050079
Al Virof7a99c52012-06-09 00:59:08 -040080static inline int is_mounted(struct vfsmount *mnt)
81{
82 /* neither detached nor internal? */
Eric W. Biederman260a4592014-01-20 15:26:15 -080083 return !IS_ERR_OR_NULL(real_mount(mnt)->mnt_ns);
Al Virof7a99c52012-06-09 00:59:08 -040084}
85
Al Viro474279d2013-10-01 16:11:26 -040086extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *);
87extern struct mount *__lookup_mnt_last(struct vfsmount *, struct dentry *);
Al Viro0226f492011-12-06 12:21:54 -050088
Al Viro48a066e2013-09-29 22:06:07 -040089extern bool legitimize_mnt(struct vfsmount *, unsigned);
90
Eric W. Biederman80b5dce2013-10-03 01:31:18 -070091extern void __detach_mounts(struct dentry *dentry);
92
93static inline void detach_mounts(struct dentry *dentry)
94{
95 if (!d_mountpoint(dentry))
96 return;
97 __detach_mounts(dentry);
98}
99
Al Viro0226f492011-12-06 12:21:54 -0500100static inline void get_mnt_ns(struct mnt_namespace *ns)
101{
102 atomic_inc(&ns->count);
103}
104
Al Viro48a066e2013-09-29 22:06:07 -0400105extern seqlock_t mount_lock;
Al Viro719ea2f2013-09-29 11:24:49 -0400106
107static inline void lock_mount_hash(void)
108{
Al Viro48a066e2013-09-29 22:06:07 -0400109 write_seqlock(&mount_lock);
Al Viro719ea2f2013-09-29 11:24:49 -0400110}
111
112static inline void unlock_mount_hash(void)
113{
Al Viro48a066e2013-09-29 22:06:07 -0400114 write_sequnlock(&mount_lock);
Al Viro719ea2f2013-09-29 11:24:49 -0400115}
116
Al Viro0226f492011-12-06 12:21:54 -0500117struct proc_mounts {
Al Viro6ce6e242012-06-09 01:16:59 -0400118 struct seq_file m;
Al Viro0226f492011-12-06 12:21:54 -0500119 struct mnt_namespace *ns;
120 struct path root;
121 int (*show)(struct seq_file *, struct vfsmount *);
Al Viroc7999c32014-02-27 14:40:10 -0500122 void *cached_mount;
123 u64 cached_event;
124 loff_t cached_index;
Al Viro0226f492011-12-06 12:21:54 -0500125};
126
Al Viro6ce6e242012-06-09 01:16:59 -0400127#define proc_mounts(p) (container_of((p), struct proc_mounts, m))
128
Al Viro0226f492011-12-06 12:21:54 -0500129extern const struct seq_operations mounts_op;
Eric W. Biederman7af13642013-10-04 19:15:13 -0700130
131extern bool __is_local_mountpoint(struct dentry *dentry);
132static inline bool is_local_mountpoint(struct dentry *dentry)
133{
134 if (!d_mountpoint(dentry))
135 return false;
136
137 return __is_local_mountpoint(dentry);
138}