1b2dba1afSAl Viro #include <linux/mount.h> 20226f492SAl Viro #include <linux/seq_file.h> 30226f492SAl Viro #include <linux/poll.h> 40226f492SAl Viro 50226f492SAl Viro struct mnt_namespace { 60226f492SAl Viro atomic_t count; 798f842e6SEric W. Biederman unsigned int proc_inum; 8be08d6d2SAl Viro struct mount * root; 90226f492SAl Viro struct list_head list; 10771b1371SEric W. Biederman struct user_namespace *user_ns; 118823c079SEric W. Biederman u64 seq; /* Sequence number to prevent loops */ 120226f492SAl Viro wait_queue_head_t poll; 13c7999c36SAl Viro u64 event; 140226f492SAl Viro }; 15b2dba1afSAl Viro 1668e8a9feSAl Viro struct mnt_pcp { 1768e8a9feSAl Viro int mnt_count; 1868e8a9feSAl Viro int mnt_writers; 1968e8a9feSAl Viro }; 2068e8a9feSAl Viro 2184d17192SAl Viro struct mountpoint { 220818bf27SAl Viro struct hlist_node m_hash; 2384d17192SAl Viro struct dentry *m_dentry; 240a5eb7c8SEric W. Biederman struct hlist_head m_list; 2584d17192SAl Viro int m_count; 2684d17192SAl Viro }; 2784d17192SAl Viro 287d6fec45SAl Viro struct mount { 2938129a13SAl Viro struct hlist_node mnt_hash; 300714a533SAl Viro struct mount *mnt_parent; 31a73324daSAl Viro struct dentry *mnt_mountpoint; 327d6fec45SAl Viro struct vfsmount mnt; 339ea459e1SAl Viro union { 3448a066e7SAl Viro struct rcu_head mnt_rcu; 359ea459e1SAl Viro struct llist_node mnt_llist; 369ea459e1SAl Viro }; 3768e8a9feSAl Viro #ifdef CONFIG_SMP 3868e8a9feSAl Viro struct mnt_pcp __percpu *mnt_pcp; 3968e8a9feSAl Viro #else 4068e8a9feSAl Viro int mnt_count; 4168e8a9feSAl Viro int mnt_writers; 4268e8a9feSAl Viro #endif 436b41d536SAl Viro struct list_head mnt_mounts; /* list of children, anchored here */ 446b41d536SAl Viro struct list_head mnt_child; /* and going through their mnt_child */ 4539f7c4dbSMiklos Szeredi struct list_head mnt_instance; /* mount instance on sb->s_mounts */ 4652ba1621SAl Viro const char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */ 471a4eeaf2SAl Viro struct list_head mnt_list; 486776db3dSAl Viro struct list_head mnt_expire; /* link in fs-specific expiry list */ 496776db3dSAl Viro struct list_head mnt_share; /* circular list of shared mounts */ 506776db3dSAl Viro struct list_head mnt_slave_list;/* list of slave mounts */ 516776db3dSAl Viro struct list_head mnt_slave; /* slave list entry */ 5232301920SAl Viro struct mount *mnt_master; /* slave is on master->mnt_slave_list */ 53143c8c91SAl Viro struct mnt_namespace *mnt_ns; /* containing namespace */ 5484d17192SAl Viro struct mountpoint *mnt_mp; /* where is it mounted */ 550a5eb7c8SEric W. Biederman struct hlist_node mnt_mp_list; /* list mounts with the same mountpoint */ 56c63181e6SAl Viro #ifdef CONFIG_FSNOTIFY 57c63181e6SAl Viro struct hlist_head mnt_fsnotify_marks; 58c63181e6SAl Viro __u32 mnt_fsnotify_mask; 59c63181e6SAl Viro #endif 6015169fe7SAl Viro int mnt_id; /* mount identifier */ 6115169fe7SAl Viro int mnt_group_id; /* peer group identifier */ 62863d684fSAl Viro int mnt_expiry_mark; /* true if marked for expiry */ 63215752fcSAl Viro struct hlist_head mnt_pins; 64aba809cfSAl Viro struct path mnt_ex_mountpoint; 657d6fec45SAl Viro }; 667d6fec45SAl Viro 67f7a99c5bSAl Viro #define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */ 68f7a99c5bSAl Viro 697d6fec45SAl Viro static inline struct mount *real_mount(struct vfsmount *mnt) 707d6fec45SAl Viro { 717d6fec45SAl Viro return container_of(mnt, struct mount, mnt); 727d6fec45SAl Viro } 737d6fec45SAl Viro 74676da58dSAl Viro static inline int mnt_has_parent(struct mount *mnt) 75b2dba1afSAl Viro { 760714a533SAl Viro return mnt != mnt->mnt_parent; 77b2dba1afSAl Viro } 78c7105365SAl Viro 79f7a99c5bSAl Viro static inline int is_mounted(struct vfsmount *mnt) 80f7a99c5bSAl Viro { 81f7a99c5bSAl Viro /* neither detached nor internal? */ 82260a459dSEric W. Biederman return !IS_ERR_OR_NULL(real_mount(mnt)->mnt_ns); 83f7a99c5bSAl Viro } 84f7a99c5bSAl Viro 85474279dcSAl Viro extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *); 86474279dcSAl Viro extern struct mount *__lookup_mnt_last(struct vfsmount *, struct dentry *); 870226f492SAl Viro 8848a066e7SAl Viro extern bool legitimize_mnt(struct vfsmount *, unsigned); 8948a066e7SAl Viro 9080b5dce8SEric W. Biederman extern void __detach_mounts(struct dentry *dentry); 9180b5dce8SEric W. Biederman 9280b5dce8SEric W. Biederman static inline void detach_mounts(struct dentry *dentry) 9380b5dce8SEric W. Biederman { 9480b5dce8SEric W. Biederman if (!d_mountpoint(dentry)) 9580b5dce8SEric W. Biederman return; 9680b5dce8SEric W. Biederman __detach_mounts(dentry); 9780b5dce8SEric W. Biederman } 9880b5dce8SEric W. Biederman 990226f492SAl Viro static inline void get_mnt_ns(struct mnt_namespace *ns) 1000226f492SAl Viro { 1010226f492SAl Viro atomic_inc(&ns->count); 1020226f492SAl Viro } 1030226f492SAl Viro 10448a066e7SAl Viro extern seqlock_t mount_lock; 105719ea2fbSAl Viro 106719ea2fbSAl Viro static inline void lock_mount_hash(void) 107719ea2fbSAl Viro { 10848a066e7SAl Viro write_seqlock(&mount_lock); 109719ea2fbSAl Viro } 110719ea2fbSAl Viro 111719ea2fbSAl Viro static inline void unlock_mount_hash(void) 112719ea2fbSAl Viro { 11348a066e7SAl Viro write_sequnlock(&mount_lock); 114719ea2fbSAl Viro } 115719ea2fbSAl Viro 1160226f492SAl Viro struct proc_mounts { 1176ce6e24eSAl Viro struct seq_file m; 1180226f492SAl Viro struct mnt_namespace *ns; 1190226f492SAl Viro struct path root; 1200226f492SAl Viro int (*show)(struct seq_file *, struct vfsmount *); 121c7999c36SAl Viro void *cached_mount; 122c7999c36SAl Viro u64 cached_event; 123c7999c36SAl Viro loff_t cached_index; 1240226f492SAl Viro }; 1250226f492SAl Viro 1266ce6e24eSAl Viro #define proc_mounts(p) (container_of((p), struct proc_mounts, m)) 1276ce6e24eSAl Viro 1280226f492SAl Viro extern const struct seq_operations mounts_op; 1297af1364fSEric W. Biederman 1307af1364fSEric W. Biederman extern bool __is_local_mountpoint(struct dentry *dentry); 1317af1364fSEric W. Biederman static inline bool is_local_mountpoint(struct dentry *dentry) 1327af1364fSEric W. Biederman { 1337af1364fSEric W. Biederman if (!d_mountpoint(dentry)) 1347af1364fSEric W. Biederman return false; 1357af1364fSEric W. Biederman 1367af1364fSEric W. Biederman return __is_local_mountpoint(dentry); 1377af1364fSEric W. Biederman } 138