To allow testing of vfork() support in the arm64 basic-gcs test provide an
implementation for nolibc, using the vfork() syscall if one is available
and otherwise clone3(). We implement in terms of clone3() since the order
of the arguments for clone() varies between architectures.
As for fork() SPARC returns the parent PID rather than 0 in the child
for vfork() so needs custom handling.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20250703-arm64-gcs-vfork-exit-v3-2-1e9a9d2ddbbe@kernel.org
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Thomas has requested that if defined() be used in place of ifdef but
currently ifdef is used consistently in sys.h. Update all the instances of
ifdef to if defined().
Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20250703-arm64-gcs-vfork-exit-v3-1-1e9a9d2ddbbe@kernel.org
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
This is the location regular userspace expects the definition.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20250430-poll-v1-1-44b5ceabdeee@linutronix.de
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Inclusion of any nolibc header file should also bring all other headers.
On the other hand it should also be possible to include any nolibc header
files
in any order.
Currently this is implemented by including the catch-all nolibc.h after the
headers own definitions.
This is problematic if one nolibc header depends on another one.
The first header has to include the other one before defining any symbols.
That in turn will include the rest of nolibc while the current header has
not defined anything yet. If any other part of nolibc depends on
definitions from the current header, errors are encountered.
This is already the case today. Effectively nolibc can only be included in
the order of nolibc.h.
Restructure the way "nolibc.h" is included.
Move it to the beginning of the header files and before the include guards.
Now any header will behave exactly like "nolibc.h" while the include
guards prevent any duplicate definitions.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20250424-nolibc-header-check-v1-2-011576b6ed6f@linutronix.de
setpgrp() is defined to be identical to setpgid(0, 0).
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Willy Tarreau <w@1wt.eu>
_exit() is the faster variant of exit(), skipping all cleanup actions.
As nolibc does not perform any cleanup anyways, the implementation is
trivial.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Willy Tarreau <w@1wt.eu>
riscv32 does not have any of the older poll systemcalls.
Use ppoll_time64 instead.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Willy Tarreau <w@1wt.eu>
riscv32 does not have any of the older select systemcalls.
Use pselect6_time64 instead.
poll() is also used to implement sleep().
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Willy Tarreau <w@1wt.eu>
The asm/ and asm-generic/ namespaces are implementation details of the UAPI
headers and not meant for direct usage.
Use the equivalent headers from the linux/ namespace instead.
While at it also drop the duplicate include of linux/signal.h from sys.h.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://lore.kernel.org/r/20250307-nolibc-asm-headers-v2-1-e2a734f25d22@linutronix.de
openat is useful to avoid needing to construct relative paths, so expose
a wrapper for using it directly.
Signed-off-by: Louis Taylor <louis@kragniz.eu>
Link: https://lore.kernel.org/r/20250306184147.208723-1-louis@kragniz.eu
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Not all architectures have the old sys_lseek(), notably riscv32.
Implement lseek() in terms of sys_llseek() in that case.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://lore.kernel.org/r/20250209-nolibc-dir-v2-1-57cc1da8558b@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
POSIX defines the signature of ioctl() as follows,
to allow passing a pointer or integer without casting:
int ioctl(int fildes, int request, ... /* arg */);
Nolibc ioctl() expects a pointer, forcing the user to manually cast.
Using va_arg to make the signature more flexible would work but seems to
prevent inlining of the function. Instead use a macro. "fd" and "req"
will still be typechecked through sys_ioctl().
Acked-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
waitid() is the modern variant of the family of wait-like syscalls.
Some architectures have dropped support for wait(), wait4() and waitpid()
but all of them support waitid().
It is more flexible and easier to use than the older ones.
Link: https://lore.kernel.org/r/20241221-nolibc-rv32-v1-1-d9ef6dab7c63@weissschuh.net
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
All supported kernels are assumed to use struct new_utsname.
This is validated in test_uname().
uname(2) can for example be used in ksft_min_kernel_version() from the
kernels selftest framework.
Link: https://lore.kernel.org/lkml/20240412123536.GA32444@redhat.com/
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
All symbols created by nolibc are also visible to user code.
Syscall constants are expected to come from the kernel headers and
should not be made up by nolibc.
Refactor the logic to avoid defining syscall numbers.
Also the new code is easier to understand.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20230917-nolibc-syscall-nr-v2-3-03863d509b9a@weissschuh.net
This allows nolic to work with `-nostdinc` avoiding any reliance on
system headers.
The implementation has been lifted from musl libc 1.2.4.
There is already an implementation of stdarg.h in include/linux/stdarg.h
but that is GPL licensed and therefore not suitable for nolibc.
The used compiler builtins have been validated to be at least available
since GCC 4.1.2 and clang 3.0.0.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
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: 428905da6e ("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>
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: 4201cfce15 ("tools/nolibc: clean up sbrk() routine")
Fixes: 924e9539ae ("tools/nolibc: clean up mmap() routine")
Fixes: d27447bc2e ("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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
