kernel/linux.git/tools/include/nolibc/sys.h, branch v6.12.80

tools/nolibc: add support for uname(2)

2024-04-14T18:28:54+00:00

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 Acked-by: Willy Tarreau

tools/nolibc: add support for getrlimit/setrlimit

2023-12-11T21:38:35+00:00

The implementation uses the prlimit64 systemcall as that is available on all architectures. Signed-off-by: Thomas Weißschuh Link: https://lore.kernel.org/lkml/20231123-nolibc-rlimit-v1-2-a428b131de2a@weissschuh.net/ Acked-by: Willy Tarreau

tools/nolibc: automatically detect necessity to use pselect6

2023-10-12T19:14:13+00:00

We can automatically detect if pselect6 is needed or not from the kernel headers. This removes the need to manually specify it. Signed-off-by: Thomas Weißschuh Acked-by: Willy Tarreau Link: https://lore.kernel.org/r/20230917-nolibc-syscall-nr-v2-4-03863d509b9a@weissschuh.net

tools/nolibc: don't define new syscall number

2023-10-12T19:14:12+00:00

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 Acked-by: Willy Tarreau Link: https://lore.kernel.org/r/20230917-nolibc-syscall-nr-v2-3-03863d509b9a@weissschuh.net

tools/nolibc: avoid unused parameter warnings for ENOSYS fallbacks

2023-10-12T19:14:10+00:00

The ENOSYS fallback code does not use its functions parameters. This can lead to compiler warnings about unused parameters. Explicitly avoid these warnings. Signed-off-by: Thomas Weißschuh Acked-by: Willy Tarreau Link: https://lore.kernel.org/r/20230917-nolibc-syscall-nr-v2-2-03863d509b9a@weissschuh.net

tools/nolibc: add stdarg.h header

2023-10-12T19:13:52+00:00

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 Signed-off-by: Willy Tarreau

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

2023-08-23T03:17:07+00:00

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 Cc: David Laight Cc: Thomas Weißschuh Signed-off-by: Willy Tarreau

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

2023-08-23T03:19:22+00:00

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 Cc: David Laight Cc: Thomas Weißschuh Signed-off-by: Willy Tarreau

tools/nolibc: sys: avoid implicit sign cast

2023-08-23T03:17:07+00:00

getauxval() returns an unsigned long but the overall type of the ternary operator needs to be signed. Signed-off-by: Thomas Weißschuh Signed-off-by: Willy Tarreau

tools/nolibc: fix return type of getpagesize()

2023-08-23T03:17:07+00:00

It's documented as returning int which is also implemented by glibc and musl, so adopt that return type. Signed-off-by: Thomas Weißschuh Signed-off-by: Willy Tarreau