1 files changed, 161 insertions, 0 deletions
diff --git a/fs/mount.h b/fs/mount.h
new file mode 100644
index 000000000..c7abb7b39
--- /dev/null
+++ b/fs/mount.h
@@ -0,0 +1,161 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/mount.h>
+#include <linux/seq_file.h>
+#include <linux/poll.h>
+#include <linux/ns_common.h>
+#include <linux/fs_pin.h>
+
+struct mnt_namespace {
+	atomic_t		count;
+	struct ns_common	ns;
+	struct mount *	root;
+	/*
+	 * Traversal and modification of .list is protected by either
+	 * - taking namespace_sem for write, OR
+	 * - taking namespace_sem for read AND taking .ns_lock.
+	 */
+	struct list_head	list;
+	spinlock_t		ns_lock;
+	struct user_namespace	*user_ns;
+	struct ucounts		*ucounts;
+	u64			seq;	/* Sequence number to prevent loops */
+	wait_queue_head_t poll;
+	u64 event;
+	unsigned int		mounts; /* # of mounts in the namespace */
+	unsigned int		pending_mounts;
+} __randomize_layout;
+
+struct mnt_pcp {
+	int mnt_count;
+	int mnt_writers;
+};
+
+struct mountpoint {
+	struct hlist_node m_hash;
+	struct dentry *m_dentry;
+	struct hlist_head m_list;
+	int m_count;
+};
+
+struct mount {
+	struct hlist_node mnt_hash;
+	struct mount *mnt_parent;
+	struct dentry *mnt_mountpoint;
+	struct vfsmount mnt;
+	union {
+		struct rcu_head mnt_rcu;
+		struct llist_node mnt_llist;
+	};
+#ifdef CONFIG_SMP
+	struct mnt_pcp __percpu *mnt_pcp;
+#else
+	int mnt_count;
+	int mnt_writers;
+#endif
+	struct list_head mnt_mounts;	/* list of children, anchored here */
+	struct list_head mnt_child;	/* and going through their mnt_child */
+	struct list_head mnt_instance;	/* mount instance on sb->s_mounts */
+	const char *mnt_devname;	/* Name of device e.g. /dev/dsk/hda1 */
+	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 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 */
+	union {
+		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;
+#endif
+	int mnt_id;			/* mount identifier */
+	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;
+} __randomize_layout;
+
+#define MNT_NS_INTERNAL ERR_PTR(-EINVAL) /* distinct from any mnt_namespace */
+
+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)
+{
+	return mnt != mnt->mnt_parent;
+}
+
+static inline int is_mounted(struct vfsmount *mnt)
+{
+	/* neither detached nor internal? */
+	return !IS_ERR_OR_NULL(real_mount(mnt)->mnt_ns);
+}
+
+extern struct mount *__lookup_mnt(struct vfsmount *, struct dentry *);
+
+extern int __legitimize_mnt(struct vfsmount *, unsigned);
+extern bool legitimize_mnt(struct vfsmount *, unsigned);
+
+static inline bool __path_is_mountpoint(const struct path *path)
+{
+	struct mount *m = __lookup_mnt(path->mnt, path->dentry);
+	return m && likely(!(m->mnt.mnt_flags & MNT_SYNC_UMOUNT));
+}
+
+extern void __detach_mounts(struct dentry *dentry);
+
+static inline void detach_mounts(struct dentry *dentry)
+{
+	if (!d_mountpoint(dentry))
+		return;
+	__detach_mounts(dentry);
+}
+
+static inline void get_mnt_ns(struct mnt_namespace *ns)
+{
+	atomic_inc(&ns->count);
+}
+
+extern seqlock_t mount_lock;
+
+static inline void lock_mount_hash(void)
+{
+	write_seqlock(&mount_lock);
+}
+
+static inline void unlock_mount_hash(void)
+{
+	write_sequnlock(&mount_lock);
+}
+
+struct proc_mounts {
+	struct mnt_namespace *ns;
+	struct path root;
+	int (*show)(struct seq_file *, struct vfsmount *);
+	struct mount cursor;
+};
+
+extern const struct seq_operations mounts_op;
+
+extern bool __is_local_mountpoint(struct dentry *dentry);
+static inline bool is_local_mountpoint(struct dentry *dentry)
+{
+	if (!d_mountpoint(dentry))
+		return false;
+
+	return __is_local_mountpoint(dentry);
+}
+
+static inline bool is_anon_ns(struct mnt_namespace *ns)
+{
+	return ns->seq == 0;
+}
+
+extern void mnt_cursor_del(struct mnt_namespace *ns, struct mount *cursor);