v4.19.13 snapshot.
diff --git a/arch/arm64/kernel/sys.c b/arch/arm64/kernel/sys.c
new file mode 100644
index 0000000..b44065f
--- /dev/null
+++ b/arch/arm64/kernel/sys.c
@@ -0,0 +1,68 @@
+/*
+ * AArch64-specific system calls implementation
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ * Author: Catalin Marinas <catalin.marinas@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/compiler.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/syscalls.h>
+
+#include <asm/cpufeature.h>
+#include <asm/syscall.h>
+
+SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
+ unsigned long, prot, unsigned long, flags,
+ unsigned long, fd, off_t, off)
+{
+ if (offset_in_page(off) != 0)
+ return -EINVAL;
+
+ return ksys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
+}
+
+SYSCALL_DEFINE1(arm64_personality, unsigned int, personality)
+{
+ if (personality(personality) == PER_LINUX32 &&
+ !system_supports_32bit_el0())
+ return -EINVAL;
+ return ksys_personality(personality);
+}
+
+/*
+ * Wrappers to pass the pt_regs argument.
+ */
+#define sys_personality sys_arm64_personality
+
+asmlinkage long sys_ni_syscall(const struct pt_regs *);
+#define __arm64_sys_ni_syscall sys_ni_syscall
+
+#undef __SYSCALL
+#define __SYSCALL(nr, sym) asmlinkage long __arm64_##sym(const struct pt_regs *);
+#include <asm/unistd.h>
+
+#undef __SYSCALL
+#define __SYSCALL(nr, sym) [nr] = (syscall_fn_t)__arm64_##sym,
+
+const syscall_fn_t sys_call_table[__NR_syscalls] = {
+ [0 ... __NR_syscalls - 1] = (syscall_fn_t)sys_ni_syscall,
+#include <asm/unistd.h>
+};