v4.19.13 snapshot.
diff --git a/arch/sh/kernel/sys_sh.c b/arch/sh/kernel/sys_sh.c
new file mode 100644
index 0000000..f8afc01
--- /dev/null
+++ b/arch/sh/kernel/sys_sh.c
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/arch/sh/kernel/sys_sh.c
+ *
+ * This file contains various random system calls that
+ * have a non-standard calling sequence on the Linux/SuperH
+ * platform.
+ *
+ * Taken from i386 version.
+ */
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/sem.h>
+#include <linux/msg.h>
+#include <linux/shm.h>
+#include <linux/stat.h>
+#include <linux/syscalls.h>
+#include <linux/mman.h>
+#include <linux/file.h>
+#include <linux/utsname.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/ipc.h>
+#include <asm/syscalls.h>
+#include <linux/uaccess.h>
+#include <asm/unistd.h>
+#include <asm/cacheflush.h>
+#include <asm/cachectl.h>
+
+asmlinkage int old_mmap(unsigned long addr, unsigned long len,
+	unsigned long prot, unsigned long flags,
+	int fd, unsigned long off)
+{
+	if (off & ~PAGE_MASK)
+		return -EINVAL;
+	return ksys_mmap_pgoff(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
+}
+
+asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
+	unsigned long prot, unsigned long flags,
+	unsigned long fd, unsigned long pgoff)
+{
+	/*
+	 * The shift for mmap2 is constant, regardless of PAGE_SIZE
+	 * setting.
+	 */
+	if (pgoff & ((1 << (PAGE_SHIFT - 12)) - 1))
+		return -EINVAL;
+
+	pgoff >>= PAGE_SHIFT - 12;
+
+	return ksys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
+}
+
+/* sys_cacheflush -- flush (part of) the processor cache.  */
+asmlinkage int sys_cacheflush(unsigned long addr, unsigned long len, int op)
+{
+	struct vm_area_struct *vma;
+
+	if ((op <= 0) || (op > (CACHEFLUSH_D_PURGE|CACHEFLUSH_I)))
+		return -EINVAL;
+
+	/*
+	 * Verify that the specified address region actually belongs
+	 * to this process.
+	 */
+	if (addr + len < addr)
+		return -EFAULT;
+
+	down_read(&current->mm->mmap_sem);
+	vma = find_vma (current->mm, addr);
+	if (vma == NULL || addr < vma->vm_start || addr + len > vma->vm_end) {
+		up_read(&current->mm->mmap_sem);
+		return -EFAULT;
+	}
+
+	switch (op & CACHEFLUSH_D_PURGE) {
+		case CACHEFLUSH_D_INVAL:
+			__flush_invalidate_region((void *)addr, len);
+			break;
+		case CACHEFLUSH_D_WB:
+			__flush_wback_region((void *)addr, len);
+			break;
+		case CACHEFLUSH_D_PURGE:
+			__flush_purge_region((void *)addr, len);
+			break;
+	}
+
+	if (op & CACHEFLUSH_I)
+		flush_icache_range(addr, addr+len);
+
+	up_read(&current->mm->mmap_sem);
+	return 0;
+}