diff options
Diffstat (limited to 'fs/mount.h')
| -rw-r--r-- | fs/mount.h | 72 |
1 files changed, 63 insertions, 9 deletions
diff --git a/fs/mount.h b/fs/mount.h index ffb613cdfeee..97737051a8b9 100644 --- a/fs/mount.h +++ b/fs/mount.h @@ -5,6 +5,8 @@ #include <linux/ns_common.h> #include <linux/fs_pin.h> +extern struct list_head notify_list; + struct mnt_namespace { struct ns_common ns; struct mount * root; @@ -20,7 +22,12 @@ struct mnt_namespace { wait_queue_head_t poll; struct rcu_head mnt_ns_rcu; }; + u64 seq_origin; /* Sequence number of origin mount namespace */ u64 event; +#ifdef CONFIG_FSNOTIFY + __u32 n_fsnotify_mask; + struct fsnotify_mark_connector __rcu *n_fsnotify_marks; +#endif unsigned int nr_mounts; /* # of mounts in the namespace */ unsigned int pending_mounts; struct rb_node mnt_ns_tree_node; /* node in the mnt_ns_tree */ @@ -37,7 +44,6 @@ struct mountpoint { struct hlist_node m_hash; struct dentry *m_dentry; struct hlist_head m_list; - int m_count; }; struct mount { @@ -63,8 +69,8 @@ struct mount { struct list_head mnt_list; struct list_head mnt_expire; /* link in fs-specific expiry list */ struct list_head mnt_share; /* circular list of shared mounts */ - struct list_head mnt_slave_list;/* list of slave mounts */ - struct list_head mnt_slave; /* slave list entry */ + struct hlist_head mnt_slave_list;/* list of slave mounts */ + struct hlist_node mnt_slave; /* slave list entry */ struct mount *mnt_master; /* slave is on master->mnt_slave_list */ struct mnt_namespace *mnt_ns; /* containing namespace */ struct mountpoint *mnt_mp; /* where is it mounted */ @@ -72,19 +78,38 @@ struct mount { struct hlist_node mnt_mp_list; /* list mounts with the same mountpoint */ struct hlist_node mnt_umount; }; - struct list_head mnt_umounting; /* list entry for umount propagation */ #ifdef CONFIG_FSNOTIFY struct fsnotify_mark_connector __rcu *mnt_fsnotify_marks; __u32 mnt_fsnotify_mask; + struct list_head to_notify; /* need to queue notification */ + struct mnt_namespace *prev_ns; /* previous namespace (NULL if none) */ #endif + int mnt_t_flags; /* namespace_sem-protected flags */ int mnt_id; /* mount identifier, reused */ u64 mnt_id_unique; /* mount ID unique until reboot */ int mnt_group_id; /* peer group identifier */ int mnt_expiry_mark; /* true if marked for expiry */ struct hlist_head mnt_pins; struct hlist_head mnt_stuck_children; + struct mount *overmount; /* mounted on ->mnt_root */ } __randomize_layout; +enum { + T_SHARED = 1, /* mount is shared */ + T_UNBINDABLE = 2, /* mount is unbindable */ + T_MARKED = 4, /* internal mark for propagate_... */ + T_UMOUNT_CANDIDATE = 8, /* for propagate_umount */ + + /* + * T_SHARED_MASK is the set of flags that should be cleared when a + * mount becomes shared. Currently, this is only the flag that says a + * mount cannot be bind mounted, since this is how we create a mount + * that shares events with another mount. If you add a new T_* + * flag, consider how it interacts with shared mounts. + */ + T_SHARED_MASK = T_UNBINDABLE, +}; + #define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */ static inline struct mount *real_mount(struct vfsmount *mnt) @@ -92,7 +117,7 @@ static inline struct mount *real_mount(struct vfsmount *mnt) return container_of(mnt, struct mount, mnt); } -static inline int mnt_has_parent(struct mount *mnt) +static inline int mnt_has_parent(const struct mount *mnt) { return mnt != mnt->mnt_parent; } @@ -137,8 +162,8 @@ struct proc_mounts { extern const struct seq_operations mounts_op; -extern bool __is_local_mountpoint(struct dentry *dentry); -static inline bool is_local_mountpoint(struct dentry *dentry) +extern bool __is_local_mountpoint(const struct dentry *dentry); +static inline bool is_local_mountpoint(const struct dentry *dentry) { if (!d_mountpoint(dentry)) return false; @@ -151,12 +176,24 @@ static inline bool is_anon_ns(struct mnt_namespace *ns) return ns->seq == 0; } +static inline bool anon_ns_root(const struct mount *m) +{ + struct mnt_namespace *ns = READ_ONCE(m->mnt_ns); + + return !IS_ERR_OR_NULL(ns) && is_anon_ns(ns) && m == ns->root; +} + static inline bool mnt_ns_attached(const struct mount *mnt) { return !RB_EMPTY_NODE(&mnt->mnt_node); } -static inline void move_from_ns(struct mount *mnt, struct list_head *dt_list) +static inline bool mnt_ns_empty(const struct mnt_namespace *ns) +{ + return RB_EMPTY_ROOT(&ns->mounts); +} + +static inline void move_from_ns(struct mount *mnt) { struct mnt_namespace *ns = mnt->mnt_ns; WARN_ON(!mnt_ns_attached(mnt)); @@ -166,7 +203,6 @@ static inline void move_from_ns(struct mount *mnt, struct list_head *dt_list) ns->mnt_first_node = rb_next(&mnt->mnt_node); rb_erase(&mnt->mnt_node, &ns->mounts); RB_CLEAR_NODE(&mnt->mnt_node); - list_add_tail(&mnt->mnt_list, dt_list); } bool has_locked_children(struct mount *mnt, struct dentry *dentry); @@ -177,3 +213,21 @@ static inline struct mnt_namespace *to_mnt_ns(struct ns_common *ns) { return container_of(ns, struct mnt_namespace, ns); } + +#ifdef CONFIG_FSNOTIFY +static inline void mnt_notify_add(struct mount *m) +{ + /* Optimize the case where there are no watches */ + if ((m->mnt_ns && m->mnt_ns->n_fsnotify_marks) || + (m->prev_ns && m->prev_ns->n_fsnotify_marks)) + list_add_tail(&m->to_notify, ¬ify_list); + else + m->prev_ns = m->mnt_ns; +} +#else +static inline void mnt_notify_add(struct mount *m) +{ +} +#endif + +struct mnt_namespace *mnt_ns_from_dentry(struct dentry *dentry); |