v4.19.13 snapshot.
diff --git a/include/linux/utsname.h b/include/linux/utsname.h
new file mode 100644
index 0000000..44429d9
--- /dev/null
+++ b/include/linux/utsname.h
@@ -0,0 +1,92 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_UTSNAME_H
+#define _LINUX_UTSNAME_H
+
+
+#include <linux/sched.h>
+#include <linux/kref.h>
+#include <linux/nsproxy.h>
+#include <linux/ns_common.h>
+#include <linux/err.h>
+#include <uapi/linux/utsname.h>
+
+enum uts_proc {
+	UTS_PROC_OSTYPE,
+	UTS_PROC_OSRELEASE,
+	UTS_PROC_VERSION,
+	UTS_PROC_HOSTNAME,
+	UTS_PROC_DOMAINNAME,
+};
+
+struct user_namespace;
+extern struct user_namespace init_user_ns;
+
+struct uts_namespace {
+	struct kref kref;
+	struct new_utsname name;
+	struct user_namespace *user_ns;
+	struct ucounts *ucounts;
+	struct ns_common ns;
+} __randomize_layout;
+extern struct uts_namespace init_uts_ns;
+
+#ifdef CONFIG_UTS_NS
+static inline void get_uts_ns(struct uts_namespace *ns)
+{
+	kref_get(&ns->kref);
+}
+
+extern struct uts_namespace *copy_utsname(unsigned long flags,
+	struct user_namespace *user_ns, struct uts_namespace *old_ns);
+extern void free_uts_ns(struct kref *kref);
+
+static inline void put_uts_ns(struct uts_namespace *ns)
+{
+	kref_put(&ns->kref, free_uts_ns);
+}
+
+void uts_ns_init(void);
+#else
+static inline void get_uts_ns(struct uts_namespace *ns)
+{
+}
+
+static inline void put_uts_ns(struct uts_namespace *ns)
+{
+}
+
+static inline struct uts_namespace *copy_utsname(unsigned long flags,
+	struct user_namespace *user_ns, struct uts_namespace *old_ns)
+{
+	if (flags & CLONE_NEWUTS)
+		return ERR_PTR(-EINVAL);
+
+	return old_ns;
+}
+
+static inline void uts_ns_init(void)
+{
+}
+#endif
+
+#ifdef CONFIG_PROC_SYSCTL
+extern void uts_proc_notify(enum uts_proc proc);
+#else
+static inline void uts_proc_notify(enum uts_proc proc)
+{
+}
+#endif
+
+static inline struct new_utsname *utsname(void)
+{
+	return &current->nsproxy->uts_ns->name;
+}
+
+static inline struct new_utsname *init_utsname(void)
+{
+	return &init_uts_ns.name;
+}
+
+extern struct rw_semaphore uts_sem;
+
+#endif /* _LINUX_UTSNAME_H */