tools/nolibc: avoid undesired casts in the __sysret() macro

Having __sysret() as an inline function has the unfortunate effect of
adding casts and large constants comparisons after the syscall retur

tools/nolibc: avoid undesired casts in the __sysret() macro

Having __sysret() as an inline function has the unfortunate effect of
adding casts and large constants comparisons after the syscall returns
that significantly inflate some light code that's otherwise syscall-
heavy. Even nolibc-test grew by ~1%.

Let's switch back to a macro for this, and use it only with signed
arguments. Note that it is also possible to design a slightly more
complex macro covering unsigned and pointers but we only have 3 such
syscalls so it is pointless, and these were just addressed not to use
this macro anymore. Now for the argument (the local variable containing
the syscall return value), any negative value is an error, that results
in -1 being returned and errno to be assigned the opposite value.

This may be revisited again in the future if really needed but for now
let's get back to something sane.

Fixes: 428905da6ec4 ("tools/nolibc: sys.h: add a syscall return helper")
Link: https://lore.kernel.org/lkml/20230806095846.GB10627@1wt.eu/
Link: https://lore.kernel.org/lkml/ZNKOJY+g66nkIyvv@1wt.eu/
Cc: Zhangjin Wu <falcon@tinylab.org>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Thomas Weißschuh <thomas@t-8ch.de>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: keep brk(), sbrk(), mmap() away from __sysret()

The __sysret() function causes some undesirable casts so we'll revert
it. In order to keep it simple it will now only support integer re

tools/nolibc: keep brk(), sbrk(), mmap() away from __sysret()

The __sysret() function causes some undesirable casts so we'll revert
it. In order to keep it simple it will now only support integer return
values like in the past, so we must basically revert the changes that
were made to these 3 syscalls which return a pointer so that they
simply rely on their own test and the SET_ERRNO() macro.

Fixes: 4201cfce15fe ("tools/nolibc: clean up sbrk() routine")
Fixes: 924e9539aeaa ("tools/nolibc: clean up mmap() routine")
Fixes: d27447bc2e0a ("tools/nolibc: sys.h: apply __sysret() helper")
Link: https://lore.kernel.org/lkml/20230806095846.GB10627@1wt.eu/
Link: https://lore.kernel.org/lkml/ZNKOJY+g66nkIyvv@1wt.eu/
Cc: Zhangjin Wu <falcon@tinylab.org>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Thomas Weißschuh <thomas@t-8ch.de>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: sys: avoid implicit sign cast

getauxval() returns an unsigned long but the overall type of the ternary
operator needs to be signed.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.n

tools/nolibc: sys: avoid implicit sign cast

getauxval() returns an unsigned long but the overall type of the ternary
operator needs to be signed.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: fix return type of getpagesize()

It's documented as returning int which is also implemented by glibc and
musl, so adopt that return type.

Signed-off-by: Thomas Weißschuh <linux@weisss

tools/nolibc: fix return type of getpagesize()

It's documented as returning int which is also implemented by glibc and
musl, so adopt that return type.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: drop unused variables

Nobody needs it, get rid of it.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>

tools/nolibc: add pipe() and pipe2() support

According to manual page [1], posix spec [2] and source code like
arch/mips/kernel/syscall.c, for historic reasons, the sys_pipe() syscall
on some archit

tools/nolibc: add pipe() and pipe2() support

According to manual page [1], posix spec [2] and source code like
arch/mips/kernel/syscall.c, for historic reasons, the sys_pipe() syscall
on some architectures has an unusual calling convention. It returns
results in two registers which means there is no need for it to do
verify the validity of a userspace pointer argument. Historically that
used to be expensive in Linux. These days the performance advantage is
negligible.

Nolibc doesn't support the unusual calling convention above, luckily
Linux provides a generic sys_pipe2() with an additional flags argument
from 2.6.27. If flags is 0, then pipe2() is the same as pipe(). So here
we use sys_pipe2() to implement the pipe().

pipe2() is also provided to allow users to use flags argument on demand.

[1]: https://man7.org/linux/man-pages/man2/pipe.2.html
[2]: https://pubs.opengroup.org/onlinepubs/9699919799/functions/pipe.html

Suggested-by: Zhangjin Wu <falcon@tinylab.org>
Link: https://lore.kernel.org/all/20230729100401.GA4577@1wt.eu/
Signed-off-by: Yuan Tan <tanyuan@tinylab.org>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: remove the old sys_stat support

The statx manpage [1] shows that it has been supported from Linux 4.11
and glibc 2.28, the Linux support can be checked for all of the
architectures wit

tools/nolibc: remove the old sys_stat support

The statx manpage [1] shows that it has been supported from Linux 4.11
and glibc 2.28, the Linux support can be checked for all of the
architectures with this command:

$ git grep -r statx v4.11 arch/ include/uapi/asm-generic/unistd.h \
| grep -E "aarch64|arm|mips|s390|x86|:include/uapi"

Besides riscv and loongarch, all of the nolibc supported architectures
have added sys_statx from Linux v4.11. riscv is mainlined to v4.15,
loongarch is mainlined to v5.19, both of them use the generic unistd.h,
so, they have added sys_statx from their first mainline versions.

The current oldest stable branch is v4.14, only reserving sys_statx
still preserves compatibility with all of the supported stable branches,
So, let's remove the old arch related and dependent sys_stat support
completely.

This is friendly to the future new architecture porting.

[1]: https://man7.org/linux/man-pages/man2/statx.2.html

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: add rmdir() support

a reverse operation of mkdir() is meaningful, add rmdir() here.

required by nolibc-test to remove /proc while CONFIG_PROC_FS is not
enabled.

Reviewed-by: Thomas W

tools/nolibc: add rmdir() support

a reverse operation of mkdir() is meaningful, add rmdir() here.

required by nolibc-test to remove /proc while CONFIG_PROC_FS is not
enabled.

Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: types.h: add RB_ flags for reboot()

Both glibc and musl provide RB_ flags via <sys/reboot.h> for reboot(),
they don't need to include <linux/reboot.h>, let nolibc provide RB_
flags too

tools/nolibc: types.h: add RB_ flags for reboot()

Both glibc and musl provide RB_ flags via <sys/reboot.h> for reboot(),
they don't need to include <linux/reboot.h>, let nolibc provide RB_
flags too.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: clean up sbrk() routine

Fix up the error reported by scripts/checkpatch.pl:

ERROR: do not use assignment in if condition
#95: FILE: tools/include/nolibc/sys.h:95:
+ if ((r

tools/nolibc: clean up sbrk() routine

Fix up the error reported by scripts/checkpatch.pl:

ERROR: do not use assignment in if condition
#95: FILE: tools/include/nolibc/sys.h:95:
+ if ((ret = sys_brk(0)) && (sys_brk(ret + inc) == ret + inc))

Apply the new generic __sysret() to merge the SET_ERRNO() and return
lines.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: clean up mmap() routine

Do several cleanups together:

- Since all supported architectures have my_syscall6() now, remove the
#ifdef check.

- Move the mmap() related macros to tools

tools/nolibc: clean up mmap() routine

Do several cleanups together:

- Since all supported architectures have my_syscall6() now, remove the
#ifdef check.

- Move the mmap() related macros to tools/include/nolibc/types.h and
reuse most of them from <linux/mman.h>

- Apply the new generic __sysret() to convert the calling of sys_map()
to oneline code

Note, since MAP_FAILED is -1 on Linux, so we can use the generic
__sysret() which returns -1 upon error and still satisfy user land that
checks for MAP_FAILED.

Suggested-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/lkml/20230702192347.GJ16233@1wt.eu/
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: __sysret: support syscalls who return a pointer

No official reference states the errno range, here aligns with musl and
glibc and uses [-MAX_ERRNO, -1] instead of all negative ones.

-

tools/nolibc: __sysret: support syscalls who return a pointer

No official reference states the errno range, here aligns with musl and
glibc and uses [-MAX_ERRNO, -1] instead of all negative ones.

- musl: src/internal/syscall_ret.c
- glibc: sysdeps/unix/sysv/linux/sysdep.h

The MAX_ERRNO used by musl and glibc is 4095, just like the one nolibc
defined in tools/include/nolibc/errno.h.

Suggested-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/lkml/ZKKdD%2Fp4UkEavru6@1wt.eu/
Suggested-by: David Laight <David.Laight@ACULAB.COM>
Link: https://lore.kernel.org/linux-riscv/94dd5170929f454fbc0a10a2eb3b108d@AcuMS.aculab.com/
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: sys.h: apply __sysret() helper

Use __sysret() to shrink most of the library routines to oneline code.

Removed 266 lines of duplicated code.

Reviewed-by: Thomas Weißschuh <linux@weiss

tools/nolibc: sys.h: apply __sysret() helper

Use __sysret() to shrink most of the library routines to oneline code.

Removed 266 lines of duplicated code.

Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: sys.h: add a syscall return helper

Most of the library routines share the same syscall return logic:

In general, a 0 return value indicates success. A -1 return value
indicates a

tools/nolibc: sys.h: add a syscall return helper

Most of the library routines share the same syscall return logic:

In general, a 0 return value indicates success. A -1 return value
indicates an error, and an error number is stored in errno. [1]

Let's add a __sysret() helper for the above logic to simplify the coding
and shrink the code lines too.

Thomas suggested to use inline function instead of macro for __sysret().

Willy suggested to make __sysret() be always inline.

[1]: https://man7.org/linux/man-pages/man2/syscall.2.html

Suggested-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/linux-riscv/ZH1+hkhiA2+ItSvX@1wt.eu/
Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/linux-riscv/ea4e7442-7223-4211-ba29-70821e907888@t-8ch.de/
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: fix up undeclared syscall macros with #ifdef and -ENOSYS

Compiling nolibc for rv32 got such errors:

nolibc/sysroot/riscv/include/sys.h: In function ‘sys_gettimeofday’:
nolibc/

tools/nolibc: fix up undeclared syscall macros with #ifdef and -ENOSYS

Compiling nolibc for rv32 got such errors:

nolibc/sysroot/riscv/include/sys.h: In function ‘sys_gettimeofday’:
nolibc/sysroot/riscv/include/sys.h:557:21: error: ‘__NR_gettimeofday’ undeclared (first use in this function); did you mean ‘sys_gettimeofday’?
557 | return my_syscall2(__NR_gettimeofday, tv, tz);
| ^~~~~~~~~~~~~~~~~
nolibc/sysroot/riscv/include/sys.h: In function ‘sys_lseek’:
nolibc/sysroot/riscv/include/sys.h:675:21: error: ‘__NR_lseek’ undeclared (first use in this function)
675 | return my_syscall3(__NR_lseek, fd, offset, whence);
| ^~~~~~~~~~
nolibc/sysroot/riscv/include/sys.h: In function ‘sys_wait4’:
nolibc/sysroot/riscv/include/sys.h:1341:21: error: ‘__NR_wait4’ undeclared (first use in this function)
1341 | return my_syscall4(__NR_wait4, pid, status, options, rusage);

If a syscall macro is not supported by a target platform, wrap it with
'#ifdef' and 'return -ENOSYS' for the '#else' branch, which lets the
other syscalls work as-is and allows developers to fix up the test
failures reported by nolibc-test one by one later.

This wraps all of the failed syscall macros with '#ifdef' and 'return
-ENOSYS' for the '#else' branch, so, all of the undeclared failures are
fixed.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/linux-riscv/5e7d2adf-e96f-41ca-a4c6-5c87a25d4c9c@app.fastmail.com/
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: fix up #error compile failures with -ENOSYS

Compiling nolibc for rv32 got such errors:

In file included from nolibc/sysroot/riscv/include/nolibc.h:99,
from no

tools/nolibc: fix up #error compile failures with -ENOSYS

Compiling nolibc for rv32 got such errors:

In file included from nolibc/sysroot/riscv/include/nolibc.h:99,
from nolibc/sysroot/riscv/include/errno.h:26,
from nolibc/sysroot/riscv/include/stdio.h:14,
from tools/testing/selftests/nolibc/nolibc-test.c:12:
nolibc/sysroot/riscv/include/sys.h:946:2: error: #error Neither __NR_ppoll nor __NR_poll defined, cannot implement sys_poll()
946 | #error Neither __NR_ppoll nor __NR_poll defined, cannot implement sys_poll()
| ^~~~~
nolibc/sysroot/riscv/include/sys.h:1062:2: error: #error None of __NR_select, __NR_pselect6, nor __NR__newselect defined, cannot implement sys_select()
1062 | #error None of __NR_select, __NR_pselect6, nor __NR__newselect defined, cannot implement sys_select()

If a syscall is not supported by a target platform, 'return -ENOSYS' is
better than '#error', which lets the other syscalls work as-is and
allows developers to fix up the test failures reported by nolibc-test
one by one later.

This converts all of the '#error' to 'return -ENOSYS', so, all of the
'#error' failures are fixed.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/linux-riscv/5e7d2adf-e96f-41ca-a4c6-5c87a25d4c9c@app.fastmail.com/
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>

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tools/nolibc: open: fix up compile warning for arm

In function ‘open’:
nolibc/sysroot/arm/include/sys.h:919:23: warning: ‘mode_t’ {aka ‘short unsigned int’} is promoted to ‘int’ when passed

tools/nolibc: open: fix up compile warning for arm

In function ‘open’:
nolibc/sysroot/arm/include/sys.h:919:23: warning: ‘mode_t’ {aka ‘short unsigned int’} is promoted to ‘int’ when passed through ‘...’
919 | mode = va_arg(args, mode_t);
| ^
nolibc/sysroot/arm/include/sys.h:919:23: note: (so you should pass ‘int’ not ‘mode_t’ {aka ‘short unsigned int’} to ‘va_arg’)
nolibc/sysroot/arm/include/sys.h:919:23: note: if this code is reached, the program will abort

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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tools/nolibc: ppoll/ppoll_time64: add a missing argument

The ppoll and ppoll_time64 syscalls have 5 arguments, but we only
provide 4, align with kernel and add the missing sigsetsize argument.

Beca

tools/nolibc: ppoll/ppoll_time64: add a missing argument

The ppoll and ppoll_time64 syscalls have 5 arguments, but we only
provide 4, align with kernel and add the missing sigsetsize argument.

Because the sigmask is NULL, the last sigsetsize argument is ignored,
keep it as 0 here is safe enough.

Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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tools/nolibc: support nanoseconds in stat()

Keep backwards compatibility through unions.

The compatibility macros like

#define st_atime st_atim.tv_sec

as documented in stat(3type) don't work for

tools/nolibc: support nanoseconds in stat()

Keep backwards compatibility through unions.

The compatibility macros like

#define st_atime st_atim.tv_sec

as documented in stat(3type) don't work for nolibc because it would
break with other stat-like structures that contain the field st_atime.

The stx_atime, stx_mtime, stx_ctime are in type of 'struct
statx_timestamp', which is incompatible with 'struct timespec', should
be converted explicitly.

/* include/uapi/linux/stat.h */

struct statx_timestamp {
__s64 tv_sec;
__u32 tv_nsec;
__s32 __reserved;
};

/* include/uapi/linux/time.h */
struct timespec {
__kernel_old_time_t tv_sec; /* seconds */
long tv_nsec; /* nanoseconds */
};

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/linux-riscv/3a3edd48-1ace-4c89-89e8-9c594dd1b3c9@t-8ch.de/
Co-authored-by: Zhangjin Wu <falcon@tinylab.org>
Signed-off-by: Zhangjin Wu <falcon@tinylab.org>
[wt: squashed Zhangjin & Thomas' patches into one to preserve "bisectability"]
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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tools/nolibc: add support for prctl()

It will be used to disable core dumps from the child spawned to validate
the stack protector functionality.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.n

tools/nolibc: add support for prctl()

It will be used to disable core dumps from the child spawned to validate
the stack protector functionality.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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tools/nolibc: remove LINUX_REBOOT_ constants

The same constants and some more have been exposed to userspace via
linux/reboot.h for a long time.

To avoid conflicts and trim down nolibc a bit drop t

tools/nolibc: remove LINUX_REBOOT_ constants

The same constants and some more have been exposed to userspace via
linux/reboot.h for a long time.

To avoid conflicts and trim down nolibc a bit drop the custom
definitions.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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tools/nolibc: s390: provide custom implementation for sys_fork

On s390 the first two arguments to the clone() syscall are swapped,
as documented in clone(2).

Signed-off-by: Thomas Weißschuh <linux@

tools/nolibc: s390: provide custom implementation for sys_fork

On s390 the first two arguments to the clone() syscall are swapped,
as documented in clone(2).

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Cc: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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tools/nolibc: use C89 comment syntax

Most of nolibc is already using C89 comments.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul

tools/nolibc: use C89 comment syntax

Most of nolibc is already using C89 comments.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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tools/nolibc: add wrapper for memfd_create

This is useful for users and will also be used by a future testcase.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <

tools/nolibc: add wrapper for memfd_create

This is useful for users and will also be used by a future testcase.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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tools/nolibc: Add statx() and make stat() rely on statx() if necessary

LoongArch and RISC-V 32-bit only have statx(). ARC, Hexagon, Nios2 and
OpenRISC have statx() and stat64() but not stat() or new

tools/nolibc: Add statx() and make stat() rely on statx() if necessary

LoongArch and RISC-V 32-bit only have statx(). ARC, Hexagon, Nios2 and
OpenRISC have statx() and stat64() but not stat() or newstat(). Add
statx() and make stat() rely on statx() if necessary to make them happy.
We may just use statx() for all architectures in the future.

Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn>
Acked-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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