openrisc: convert to generic syscall table

The uapi/asm/unistd_32.h and asm/syscall_table_32.h headers can now be
generated from scripts/syscall.tbl, which makes this consistent with
the other architectures that have their own syscall.tbl.

openrisc has one extra system call that gets added to scripts/syscall.tbl.

The time32, stat64, rlimit and renameat entries in the syscall_abis_32
line are for system calls that were part of the generic ABI when
arch/nios2 got added but are no longer enabled by default for new
architectures.

Both the user visible side of asm/unistd.h and the internal syscall
table in the kernel should have the same effective contents after this.

When asm/syscalls.h is included in kernel/fork.c for the purpose of
type checking, the redirection macros cause problems. Move these so
only the references get redirected.

Signed-off-by: Arnd Bergmann <[e-mail]>

arch/openrisc/include/asm/Kbuild

···
 # SPDX-License-Identifier: GPL-2.0
+syscall-y += syscall_table_32.h
+
 generic-y += extable.h
 generic-y += kvm_para.h
 generic-y += parport.h

arch/openrisc/include/asm/syscalls.h

···
 asmlinkage long __sys_clone3(struct clone_args __user *uargs, size_t size);
 asmlinkage long __sys_fork(void);
 
-#define sys_clone __sys_clone
-#define sys_clone3 __sys_clone3
-#define sys_fork __sys_fork
-
 #endif /* __ASM_OPENRISC_SYSCALLS_H */

arch/openrisc/include/asm/unistd.h

···
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+
+#define __ARCH_WANT_STAT64
+#define __ARCH_WANT_SYS_FORK
+#define __ARCH_WANT_SYS_CLONE
+#define __ARCH_WANT_TIME32_SYSCALLS
+
+#include <uapi/asm/unistd.h>

arch/openrisc/include/uapi/asm/Kbuild

···
 # SPDX-License-Identifier: GPL-2.0
+syscall-y += unistd_32.h
+
 generic-y += ucontext.h

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

···
  * (at your option) any later version.
  */
 
-#define sys_mmap2 sys_mmap_pgoff
-
-#define __ARCH_WANT_RENAMEAT
-#define __ARCH_WANT_STAT64
-#define __ARCH_WANT_SET_GET_RLIMIT
-#define __ARCH_WANT_SYS_FORK
-#define __ARCH_WANT_SYS_CLONE
-#define __ARCH_WANT_TIME32_SYSCALLS
-
-#include <asm-generic/unistd.h>
-
-#define __NR_or1k_atomic __NR_arch_specific_syscall
-__SYSCALL(__NR_or1k_atomic, sys_or1k_atomic)
+#include <asm/unistd_32.h>

arch/openrisc/kernel/Makefile.syscalls

···
+# SPDX-License-Identifier: GPL-2.0
+
+syscall_abis_32 += or1k time32 stat64 rlimit renameat

arch/openrisc/kernel/sys_call_table.c

···
 
 #include <asm/syscalls.h>
 
-#undef __SYSCALL
 #define __SYSCALL(nr, call) [nr] = (call),
+#define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, native)
+
+#define sys_mmap2 sys_mmap_pgoff
+#define sys_clone __sys_clone
+#define sys_clone3 __sys_clone3
+#define sys_fork __sys_fork
 
 void *sys_call_table[__NR_syscalls] = {
-#include <asm/unistd.h>
+#include <asm/syscall_table_32.h>
 };

scripts/syscall.tbl

···
 
 244	nios2	cacheflush			sys_cacheflush
 
+244	or1k	or1k_atomic			sys_or1k_atomic
+
 260	time32	wait4				sys_wait4			compat_sys_wait4
 260	64	wait4				sys_wait4
 261	common	prlimit64			sys_prlimit64