We don't want new architectures to even provide the old 32-bit time_t
based system calls any more, or define the syscall number macros.
Add a new __ARCH_WANT_TIME32_SYSCALLS macro that gets enabled for all
existing 32-bit architectures using the generic system call table,
so we don't change any current behavior.
Since this symbol is evaluated in user space as well, we cannot use
a Kconfig CONFIG_* macro but have to define it in uapi/asm/unistd.h.
On 64-bit architectures, the same system call numbers mostly refer to
the system calls we want to keep, as they already pass 64-bit time_t.
As new architectures no longer provide these, we need new exceptions
in checksyscalls.sh.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
New architectures should no longer need stat64, which is not y2038
safe and has been replaced by statx(). This removes the 'select
__ARCH_WANT_STAT64' statement from asm-generic/unistd.h and instead
moves it into the respective asm/unistd.h UAPI header files for each
architecture that uses it today.
In the generic file, the system call number and entry points are now
made conditional, so newly added architectures (e.g. riscv32 or csky)
will never need to carry backwards compatiblity for it.
arm64 is the only 64-bit architecture using the asm-generic/unistd.h
file, and it already sets __ARCH_WANT_NEW_STAT in its headers, and I
use the same #ifdef here: future 64-bit architectures therefore won't
see newstat or stat64 any more. They don't suffer from the y2038 time_t
overflow, but for consistency it seems best to also let them use statx().
Signed-off-by: Arnd Bergmann <arnd@arndb.de>