arm64: generate 64-bit syscall.tbl

Change the asm/unistd.h header for arm64 to no longer include
asm-generic/unistd.h itself, but instead generate both the asm/unistd.h
contents and the list of entry points using the syscall.tbl scripts that
we use on most other architectures.

Once his is done for the remaining architectures, the generic unistd.h
header can be removed and the generated tbl file put in its place.

The Makefile changes are more complex than they should be, I need
a little help to improve those. Ideally this should be done in an
architecture-independent way as well.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/arm64/include/asm/Kbuild

@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 syscall-y += syscall_table_32.h
+syscall-y += syscall_table_64.h
 
 # arm32 syscall table used by lib/compat_audit.c:
 syscall-y += unistd_32.h

arch/arm64/include/asm/seccomp.h

@@ -23,6 +23,7 @@
 #define SECCOMP_ARCH_NATIVE_NR		NR_syscalls
 #define SECCOMP_ARCH_NATIVE_NAME	"aarch64"
 #ifdef CONFIG_COMPAT
+#include <asm/unistd_compat_32.h>
 # define SECCOMP_ARCH_COMPAT		AUDIT_ARCH_ARM
 # define SECCOMP_ARCH_COMPAT_NR		__NR_compat32_syscalls
 # define SECCOMP_ARCH_COMPAT_NAME	"arm"

arch/arm64/include/asm/unistd.h

@@ -41,9 +41,8 @@
 #endif
 
 #define __ARCH_WANT_SYS_CLONE
+#define __ARCH_WANT_NEW_STAT
 
-#ifndef __COMPAT_SYSCALL_NR
-#include <uapi/asm/unistd.h>
-#endif
+#include <asm/unistd_64.h>
 
 #define NR_syscalls (__NR_syscalls)

arch/arm64/include/uapi/asm/Kbuild

@@ -1,3 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
+syscall-y += unistd_64.h
 
 generic-y += kvm_para.h

arch/arm64/include/uapi/asm/unistd.h

@@ -1,24 +1,2 @@
 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
-/*
- * 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/>.
- */
-
-#define __ARCH_WANT_RENAMEAT
-#define __ARCH_WANT_NEW_STAT
-#define __ARCH_WANT_SET_GET_RLIMIT
-#define __ARCH_WANT_TIME32_SYSCALLS
-#define __ARCH_WANT_MEMFD_SECRET
-
-#include <asm-generic/unistd.h>
+#include <asm/unistd_64.h>

arch/arm64/kernel/Makefile.syscalls

@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 
 syscall_abis_32 +=
+syscall_abis_64 += renameat newstat rlimit memfd_secret
 
 syscalltbl = arch/arm64/tools/syscall_%.tbl

arch/arm64/kernel/sys.c

@@ -48,14 +48,16 @@ asmlinkage long __arm64_sys_ni_syscall(const struct pt_regs *__unused)
  */
 #define __arm64_sys_personality		__arm64_sys_arm64_personality
 
+#define __SYSCALL_WITH_COMPAT(nr, native, compat)  __SYSCALL(nr, native)
+
 #undef __SYSCALL
 #define __SYSCALL(nr, sym)	asmlinkage long __arm64_##sym(const struct pt_regs *);
-#include <asm/unistd.h>
+#include <asm/syscall_table_64.h>
 
 #undef __SYSCALL
 #define __SYSCALL(nr, sym)	[nr] = __arm64_##sym,
 
 const syscall_fn_t sys_call_table[__NR_syscalls] = {
 	[0 ... __NR_syscalls - 1] = __arm64_sys_ni_syscall,
-#include <asm/unistd.h>
+#include <asm/syscall_table_64.h>
 };

arch/arm64/tools/Makefile

@@ -3,12 +3,16 @@
 gen := arch/$(ARCH)/include/generated
 kapi := $(gen)/asm
 
-kapi-hdrs-y := $(kapi)/cpucap-defs.h $(kapi)/sysreg-defs.h
+kapisyshdr-y := cpucap-defs.h sysreg-defs.h
+
+kapi-hdrs-y := $(addprefix $(kapi)/, $(kapisyshdr-y))
 
 targets += $(addprefix ../../../, $(kapi-hdrs-y))
 
 PHONY += kapi
 
+all: $(syscall64) kapi
+
 kapi:   $(kapi-hdrs-y)
 
 quiet_cmd_gen_cpucaps = GEN     $@

arch/arm64/tools/syscall_64.tbl

@@ -0,0 +1 @@
+../../../scripts/syscall.tbl