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149 lines
4.0 KiB
149 lines
4.0 KiB
/* SPDX-License-Identifier: GPL-2.0 */ |
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#include <linux/mount.h> |
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#include <linux/seq_file.h> |
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#include <linux/poll.h> |
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#include <linux/ns_common.h> |
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#include <linux/fs_pin.h> |
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struct mnt_namespace { |
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struct ns_common ns; |
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struct mount * root; |
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/* |
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* Traversal and modification of .list is protected by either |
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* - taking namespace_sem for write, OR |
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* - taking namespace_sem for read AND taking .ns_lock. |
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*/ |
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struct list_head list; |
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spinlock_t ns_lock; |
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struct user_namespace *user_ns; |
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struct ucounts *ucounts; |
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u64 seq; /* Sequence number to prevent loops */ |
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wait_queue_head_t poll; |
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u64 event; |
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unsigned int mounts; /* # of mounts in the namespace */ |
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unsigned int pending_mounts; |
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} __randomize_layout; |
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struct mnt_pcp { |
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int mnt_count; |
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int mnt_writers; |
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}; |
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struct mountpoint { |
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struct hlist_node m_hash; |
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struct dentry *m_dentry; |
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struct hlist_head m_list; |
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int m_count; |
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}; |
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struct mount { |
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struct hlist_node mnt_hash; |
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struct mount *mnt_parent; |
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struct dentry *mnt_mountpoint; |
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struct vfsmount mnt; |
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union { |
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struct rcu_head mnt_rcu; |
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struct llist_node mnt_llist; |
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}; |
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#ifdef CONFIG_SMP |
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struct mnt_pcp __percpu *mnt_pcp; |
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#else |
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int mnt_count; |
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int mnt_writers; |
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#endif |
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struct list_head mnt_mounts; /* list of children, anchored here */ |
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struct list_head mnt_child; /* and going through their mnt_child */ |
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struct list_head mnt_instance; /* mount instance on sb->s_mounts */ |
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const char *mnt_devname; /* Name of device e.g. /dev/dsk/hda1 */ |
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struct list_head mnt_list; |
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struct list_head mnt_expire; /* link in fs-specific expiry list */ |
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struct list_head mnt_share; /* circular list of shared mounts */ |
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struct list_head mnt_slave_list;/* list of slave mounts */ |
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struct list_head mnt_slave; /* slave list entry */ |
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struct mount *mnt_master; /* slave is on master->mnt_slave_list */ |
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struct mnt_namespace *mnt_ns; /* containing namespace */ |
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struct mountpoint *mnt_mp; /* where is it mounted */ |
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union { |
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struct hlist_node mnt_mp_list; /* list mounts with the same mountpoint */ |
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struct hlist_node mnt_umount; |
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}; |
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struct list_head mnt_umounting; /* list entry for umount propagation */ |
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#ifdef CONFIG_FSNOTIFY |
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struct fsnotify_mark_connector __rcu *mnt_fsnotify_marks; |
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__u32 mnt_fsnotify_mask; |
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#endif |
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int mnt_id; /* mount identifier */ |
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int mnt_group_id; /* peer group identifier */ |
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int mnt_expiry_mark; /* true if marked for expiry */ |
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struct hlist_head mnt_pins; |
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struct hlist_head mnt_stuck_children; |
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} __randomize_layout; |
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#define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */ |
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static inline struct mount *real_mount(struct vfsmount *mnt) |
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{ |
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return container_of(mnt, struct mount, mnt); |
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} |
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static inline int mnt_has_parent(struct mount *mnt) |
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{ |
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return mnt != mnt->mnt_parent; |
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} |
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static inline int is_mounted(struct vfsmount *mnt) |
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{ |
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/* neither detached nor internal? */ |
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return !IS_ERR_OR_NULL(real_mount(mnt)->mnt_ns); |
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} |
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extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *); |
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extern int __legitimize_mnt(struct vfsmount *, unsigned); |
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static inline bool __path_is_mountpoint(const struct path *path) |
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{ |
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struct mount *m = __lookup_mnt(path->mnt, path->dentry); |
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return m && likely(!(m->mnt.mnt_flags & MNT_SYNC_UMOUNT)); |
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} |
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extern void __detach_mounts(struct dentry *dentry); |
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static inline void detach_mounts(struct dentry *dentry) |
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{ |
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if (!d_mountpoint(dentry)) |
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return; |
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__detach_mounts(dentry); |
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} |
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static inline void get_mnt_ns(struct mnt_namespace *ns) |
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{ |
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refcount_inc(&ns->ns.count); |
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} |
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extern seqlock_t mount_lock; |
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struct proc_mounts { |
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struct mnt_namespace *ns; |
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struct path root; |
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int (*show)(struct seq_file *, struct vfsmount *); |
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struct mount cursor; |
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}; |
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extern const struct seq_operations mounts_op; |
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extern bool __is_local_mountpoint(struct dentry *dentry); |
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static inline bool is_local_mountpoint(struct dentry *dentry) |
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{ |
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if (!d_mountpoint(dentry)) |
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return false; |
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return __is_local_mountpoint(dentry); |
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} |
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static inline bool is_anon_ns(struct mnt_namespace *ns) |
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{ |
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return ns->seq == 0; |
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} |
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extern void mnt_cursor_del(struct mnt_namespace *ns, struct mount *cursor);
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