v4.19.13 snapshot.
diff --git a/arch/arm64/include/asm/syscall.h b/arch/arm64/include/asm/syscall.h
new file mode 100644
index 0000000..ad8be16
--- /dev/null
+++ b/arch/arm64/include/asm/syscall.h
@@ -0,0 +1,128 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * 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/>.
+ */
+#ifndef __ASM_SYSCALL_H
+#define __ASM_SYSCALL_H
+
+#include <uapi/linux/audit.h>
+#include <linux/compat.h>
+#include <linux/err.h>
+
+typedef long (*syscall_fn_t)(struct pt_regs *regs);
+
+extern const syscall_fn_t sys_call_table[];
+
+#ifdef CONFIG_COMPAT
+extern const syscall_fn_t compat_sys_call_table[];
+#endif
+
+static inline int syscall_get_nr(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ return regs->syscallno;
+}
+
+static inline void syscall_rollback(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ regs->regs[0] = regs->orig_x0;
+}
+
+
+static inline long syscall_get_error(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ unsigned long error = regs->regs[0];
+ return IS_ERR_VALUE(error) ? error : 0;
+}
+
+static inline long syscall_get_return_value(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ return regs->regs[0];
+}
+
+static inline void syscall_set_return_value(struct task_struct *task,
+ struct pt_regs *regs,
+ int error, long val)
+{
+ regs->regs[0] = (long) error ? error : val;
+}
+
+#define SYSCALL_MAX_ARGS 6
+
+static inline void syscall_get_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned int i, unsigned int n,
+ unsigned long *args)
+{
+ if (n == 0)
+ return;
+
+ if (i + n > SYSCALL_MAX_ARGS) {
+ unsigned long *args_bad = args + SYSCALL_MAX_ARGS - i;
+ unsigned int n_bad = n + i - SYSCALL_MAX_ARGS;
+ pr_warning("%s called with max args %d, handling only %d\n",
+ __func__, i + n, SYSCALL_MAX_ARGS);
+ memset(args_bad, 0, n_bad * sizeof(args[0]));
+ }
+
+ if (i == 0) {
+ args[0] = regs->orig_x0;
+ args++;
+ i++;
+ n--;
+ }
+
+ memcpy(args, ®s->regs[i], n * sizeof(args[0]));
+}
+
+static inline void syscall_set_arguments(struct task_struct *task,
+ struct pt_regs *regs,
+ unsigned int i, unsigned int n,
+ const unsigned long *args)
+{
+ if (n == 0)
+ return;
+
+ if (i + n > SYSCALL_MAX_ARGS) {
+ pr_warning("%s called with max args %d, handling only %d\n",
+ __func__, i + n, SYSCALL_MAX_ARGS);
+ n = SYSCALL_MAX_ARGS - i;
+ }
+
+ if (i == 0) {
+ regs->orig_x0 = args[0];
+ args++;
+ i++;
+ n--;
+ }
+
+ memcpy(®s->regs[i], args, n * sizeof(args[0]));
+}
+
+/*
+ * We don't care about endianness (__AUDIT_ARCH_LE bit) here because
+ * AArch64 has the same system calls both on little- and big- endian.
+ */
+static inline int syscall_get_arch(void)
+{
+ if (is_compat_task())
+ return AUDIT_ARCH_ARM;
+
+ return AUDIT_ARCH_AARCH64;
+}
+
+#endif /* __ASM_SYSCALL_H */