1b2dba1afSAl Viro #include <linux/mount.h> 20226f492SAl Viro #include <linux/seq_file.h> 30226f492SAl Viro #include <linux/poll.h> 4435d5f4bSAl Viro #include <linux/ns_common.h> 587b95ce0SAl Viro #include <linux/fs_pin.h> 60226f492SAl Viro 70226f492SAl Viro struct mnt_namespace { 80226f492SAl Viro atomic_t count; 9435d5f4bSAl Viro struct ns_common ns; 10be08d6d2SAl Viro struct mount * root; 110226f492SAl Viro struct list_head list; 12771b1371SEric W. Biederman struct user_namespace *user_ns; 13537f7ccbSEric W. Biederman struct ucounts *ucounts; 148823c079SEric W. Biederman u64 seq; /* Sequence number to prevent loops */ 150226f492SAl Viro wait_queue_head_t poll; 16c7999c36SAl Viro u64 event; 17d2921684SEric W. Biederman unsigned int mounts; /* # of mounts in the namespace */ 18d2921684SEric W. Biederman unsigned int pending_mounts; 190226f492SAl Viro }; 20b2dba1afSAl Viro 2168e8a9feSAl Viro struct mnt_pcp { 2268e8a9feSAl Viro int mnt_count; 2368e8a9feSAl Viro int mnt_writers; 2468e8a9feSAl Viro }; 2568e8a9feSAl Viro 2684d17192SAl Viro struct mountpoint { 270818bf27SAl Viro struct hlist_node m_hash; 2884d17192SAl Viro struct dentry *m_dentry; 290a5eb7c8SEric W. Biederman struct hlist_head m_list; 3084d17192SAl Viro int m_count; 3184d17192SAl Viro }; 3284d17192SAl Viro 337d6fec45SAl Viro struct mount { 3438129a13SAl Viro struct hlist_node mnt_hash; 350714a533SAl Viro struct mount *mnt_parent; 36a73324daSAl Viro struct dentry *mnt_mountpoint; 377d6fec45SAl Viro struct vfsmount mnt; 389ea459e1SAl Viro union { 3948a066e7SAl Viro struct rcu_head mnt_rcu; 409ea459e1SAl Viro struct llist_node mnt_llist; 419ea459e1SAl Viro }; 4268e8a9feSAl Viro #ifdef CONFIG_SMP 4368e8a9feSAl Viro struct mnt_pcp __percpu *mnt_pcp; 4468e8a9feSAl Viro #else 4568e8a9feSAl Viro int mnt_count; 4668e8a9feSAl Viro int mnt_writers; 4768e8a9feSAl Viro #endif 486b41d536SAl Viro struct list_head mnt_mounts; /* list of children, anchored here */ 496b41d536SAl Viro struct list_head mnt_child; /* and going through their mnt_child */ 5039f7c4dbSMiklos Szeredi struct list_head mnt_instance; /* mount instance on sb->s_mounts */ 5152ba1621SAl Viro const char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */ 521a4eeaf2SAl Viro struct list_head mnt_list; 536776db3dSAl Viro struct list_head mnt_expire; /* link in fs-specific expiry list */ 546776db3dSAl Viro struct list_head mnt_share; /* circular list of shared mounts */ 556776db3dSAl Viro struct list_head mnt_slave_list;/* list of slave mounts */ 566776db3dSAl Viro struct list_head mnt_slave; /* slave list entry */ 5732301920SAl Viro struct mount *mnt_master; /* slave is on master->mnt_slave_list */ 58143c8c91SAl Viro struct mnt_namespace *mnt_ns; /* containing namespace */ 5984d17192SAl Viro struct mountpoint *mnt_mp; /* where is it mounted */ 600a5eb7c8SEric W. Biederman struct hlist_node mnt_mp_list; /* list mounts with the same mountpoint */ 61c63181e6SAl Viro #ifdef CONFIG_FSNOTIFY 6208991e83SJan Kara struct fsnotify_mark_connector __rcu *mnt_fsnotify_marks; 63c63181e6SAl Viro __u32 mnt_fsnotify_mask; 64c63181e6SAl Viro #endif 6515169fe7SAl Viro int mnt_id; /* mount identifier */ 6615169fe7SAl Viro int mnt_group_id; /* peer group identifier */ 67863d684fSAl Viro int mnt_expiry_mark; /* true if marked for expiry */ 68215752fcSAl Viro struct hlist_head mnt_pins; 6987b95ce0SAl Viro struct fs_pin mnt_umount; 7087b95ce0SAl Viro struct dentry *mnt_ex_mountpoint; 717d6fec45SAl Viro }; 727d6fec45SAl Viro 73f7a99c5bSAl Viro #define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */ 74f7a99c5bSAl Viro 757d6fec45SAl Viro static inline struct mount *real_mount(struct vfsmount *mnt) 767d6fec45SAl Viro { 777d6fec45SAl Viro return container_of(mnt, struct mount, mnt); 787d6fec45SAl Viro } 797d6fec45SAl Viro 80676da58dSAl Viro static inline int mnt_has_parent(struct mount *mnt) 81b2dba1afSAl Viro { 820714a533SAl Viro return mnt != mnt->mnt_parent; 83b2dba1afSAl Viro } 84c7105365SAl Viro 85f7a99c5bSAl Viro static inline int is_mounted(struct vfsmount *mnt) 86f7a99c5bSAl Viro { 87f7a99c5bSAl Viro /* neither detached nor internal? */ 88260a459dSEric W. Biederman return !IS_ERR_OR_NULL(real_mount(mnt)->mnt_ns); 89f7a99c5bSAl Viro } 90f7a99c5bSAl Viro 91474279dcSAl Viro extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *); 920226f492SAl Viro 93294d71ffSAl Viro extern int __legitimize_mnt(struct vfsmount *, unsigned); 9448a066e7SAl Viro extern bool legitimize_mnt(struct vfsmount *, unsigned); 9548a066e7SAl Viro 96c6609c0aSIan Kent static inline bool __path_is_mountpoint(const struct path *path) 97c6609c0aSIan Kent { 98c6609c0aSIan Kent struct mount *m = __lookup_mnt(path->mnt, path->dentry); 99c6609c0aSIan Kent return m && likely(!(m->mnt.mnt_flags & MNT_SYNC_UMOUNT)); 100c6609c0aSIan Kent } 101c6609c0aSIan Kent 10280b5dce8SEric W. Biederman extern void __detach_mounts(struct dentry *dentry); 10380b5dce8SEric W. Biederman 10480b5dce8SEric W. Biederman static inline void detach_mounts(struct dentry *dentry) 10580b5dce8SEric W. Biederman { 10680b5dce8SEric W. Biederman if (!d_mountpoint(dentry)) 10780b5dce8SEric W. Biederman return; 10880b5dce8SEric W. Biederman __detach_mounts(dentry); 10980b5dce8SEric W. Biederman } 11080b5dce8SEric W. Biederman 1110226f492SAl Viro static inline void get_mnt_ns(struct mnt_namespace *ns) 1120226f492SAl Viro { 1130226f492SAl Viro atomic_inc(&ns->count); 1140226f492SAl Viro } 1150226f492SAl Viro 11648a066e7SAl Viro extern seqlock_t mount_lock; 117719ea2fbSAl Viro 118719ea2fbSAl Viro static inline void lock_mount_hash(void) 119719ea2fbSAl Viro { 12048a066e7SAl Viro write_seqlock(&mount_lock); 121719ea2fbSAl Viro } 122719ea2fbSAl Viro 123719ea2fbSAl Viro static inline void unlock_mount_hash(void) 124719ea2fbSAl Viro { 12548a066e7SAl Viro write_sequnlock(&mount_lock); 126719ea2fbSAl Viro } 127719ea2fbSAl Viro 1280226f492SAl Viro struct proc_mounts { 1290226f492SAl Viro struct mnt_namespace *ns; 1300226f492SAl Viro struct path root; 1310226f492SAl Viro int (*show)(struct seq_file *, struct vfsmount *); 132c7999c36SAl Viro void *cached_mount; 133c7999c36SAl Viro u64 cached_event; 134c7999c36SAl Viro loff_t cached_index; 1350226f492SAl Viro }; 1360226f492SAl Viro 1370226f492SAl Viro extern const struct seq_operations mounts_op; 1387af1364fSEric W. Biederman 1397af1364fSEric W. Biederman extern bool __is_local_mountpoint(struct dentry *dentry); 1407af1364fSEric W. Biederman static inline bool is_local_mountpoint(struct dentry *dentry) 1417af1364fSEric W. Biederman { 1427af1364fSEric W. Biederman if (!d_mountpoint(dentry)) 1437af1364fSEric W. Biederman return false; 1447af1364fSEric W. Biederman 1457af1364fSEric W. Biederman return __is_local_mountpoint(dentry); 1467af1364fSEric W. Biederman } 147