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-rw-r--r--fs/mount.h149
1 files changed, 149 insertions, 0 deletions
diff --git a/fs/mount.h b/fs/mount.h
new file mode 100644
index 000000000..130c07c2f
--- /dev/null
+++ b/fs/mount.h
@@ -0,0 +1,149 @@
+/* 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 {
+ 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);
+
+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)
+{
+ refcount_inc(&ns->ns.count);
+}
+
+extern seqlock_t 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);