v4.19.13 snapshot.
diff --git a/include/linux/shm.h b/include/linux/shm.h
new file mode 100644
index 0000000..d8e69ae
--- /dev/null
+++ b/include/linux/shm.h
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_SHM_H_
+#define _LINUX_SHM_H_
+
+#include <linux/list.h>
+#include <asm/page.h>
+#include <uapi/linux/shm.h>
+#include <asm/shmparam.h>
+
+struct file;
+
+#ifdef CONFIG_SYSVIPC
+struct sysv_shm {
+ struct list_head shm_clist;
+};
+
+long do_shmat(int shmid, char __user *shmaddr, int shmflg, unsigned long *addr,
+ unsigned long shmlba);
+bool is_file_shm_hugepages(struct file *file);
+void exit_shm(struct task_struct *task);
+#define shm_init_task(task) INIT_LIST_HEAD(&(task)->sysvshm.shm_clist)
+#else
+struct sysv_shm {
+ /* empty */
+};
+
+static inline long do_shmat(int shmid, char __user *shmaddr,
+ int shmflg, unsigned long *addr,
+ unsigned long shmlba)
+{
+ return -ENOSYS;
+}
+static inline bool is_file_shm_hugepages(struct file *file)
+{
+ return false;
+}
+static inline void exit_shm(struct task_struct *task)
+{
+}
+static inline void shm_init_task(struct task_struct *task)
+{
+}
+#endif
+
+#endif /* _LINUX_SHM_H_ */