kernel/linux.git/tools/include/nolibc/sys.h, branch v6.1.168

tools/nolibc: fix missing includes causing build issues at -O0

2023-02-01T07:34:31+00:00

[ Upstream commit 55abdd1f5e1e07418bf4a46c233a92f83cb5ae97 ] After the nolibc includes were split to facilitate portability from standard libcs, programs that include only what they need may miss some symbols which are needed by libgcc. This is the case for raise() which is needed by the divide by zero code in some architectures for example. Regardless, being able to include only the apparently needed files is convenient. Instead of trying to move all exported definitions to a single file, since this can change over time, this patch takes another approach consisting in including the nolibc header at the end of all standard include files. This way their types and functions are already known at the moment of inclusion, and including any single one of them is sufficient to bring all the required ones. Signed-off-by: Willy Tarreau Signed-off-by: Paul E. McKenney Signed-off-by: Sasha Levin

tools/nolibc: make sys_mmap() automatically use the right __NR_mmap definition

2022-08-31T12:17:43+00:00

__NR_mmap2 was used for i386 but it's also needed for other archs such as RISCV32 or ARM. Let's decide to use it based on the __NR_mmap2 definition as it's not defined on other archs. Signed-off-by: Willy Tarreau Signed-off-by: Paul E. McKenney

tools/nolibc: fix build warning in sys_mmap() when my_syscall6 is not defined

2022-08-31T12:17:43+00:00

We return -ENOSYS when there's no syscall6() operation, but we must cast it to void* to avoid a warning. Signed-off-by: Willy Tarreau Signed-off-by: Paul E. McKenney

tools/nolibc/sys: Implement `mmap()` and `munmap()`

2022-04-21T00:05:46+00:00

Implement mmap() and munmap(). Currently, they are only available for architecures that have my_syscall6 macro. For architectures that don't have, this function will return -1 with errno set to ENOSYS (Function not implemented). This has been tested on x86 and i386. Notes for i386: 1) The common mmap() syscall implementation uses __NR_mmap2 instead of __NR_mmap. 2) The offset must be shifted-right by 12-bit. Acked-by: Willy Tarreau Signed-off-by: Ammar Faizi Signed-off-by: Paul E. McKenney

tools/nolibc/sys: add syscall definition for getppid()

2022-04-21T00:05:45+00:00

This is essentially for completeness as it's not the most often used in regtests. Signed-off-by: Willy Tarreau Signed-off-by: Paul E. McKenney

tools/nolibc/errno: extract errno.h from sys.h

2022-04-21T00:05:45+00:00

This allows us to provide a minimal errno.h to ease porting applications that use it. Signed-off-by: Willy Tarreau Signed-off-by: Paul E. McKenney

tools/nolibc/sys: make getpgrp(), getpid(), gettid() not set errno

2022-04-21T00:05:44+00:00

These syscalls never fail so there is no need to extract and set errno for them. Signed-off-by: Willy Tarreau Signed-off-by: Paul E. McKenney

tools/nolibc/sys: make open() take a vararg on the 3rd argument

2022-04-21T00:05:44+00:00

Let's pass a vararg to open() so that it remains compatible with existing code. The arg is only dereferenced when flags contain O_CREAT. The function is generally not inlined anymore, causing an extra call (total 16 extra bytes) but it's still optimized for constant propagation, limiting the excess to no more than 16 bytes in practice when open() is called without O_CREAT, and ~40 with O_CREAT, which remains reasonable. Signed-off-by: Willy Tarreau Signed-off-by: Paul E. McKenney

tools/nolibc/sys: split the syscall definitions into their own file

2022-04-21T00:05:43+00:00

The syscall definitions were moved to sys.h. They were arranged in a more easily maintainable order, whereby the sys_xxx() and xxx() functions were grouped together, which also enlights the occasional mappings such as wait relying on wait4(). Signed-off-by: Willy Tarreau Signed-off-by: Paul E. McKenney