diff options
| -rw-r--r-- | sysdeps/unix/sysv/linux/arc/clone3.S | 90 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/arc/sysdep.h | 2 |
2 files changed, 92 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/arc/clone3.S b/sysdeps/unix/sysv/linux/arc/clone3.S new file mode 100644 index 0000000..87a8272 --- /dev/null +++ b/sysdeps/unix/sysv/linux/arc/clone3.S @@ -0,0 +1,90 @@ +/* The clone3 syscall wrapper. Linux/arc version. + Copyright (C) 2023 Free Software Foundation, Inc. + + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +#include <sysdep.h> +#define _ERRNO_H 1 +#include <bits/errno.h> + +/* The userland implementation is: + int clone3 (struct clone_args *cl_args, size_t size, + int (*func)(void *arg), void *arg); + + the kernel entry is: + int clone3 (struct clone_args *cl_args, size_t size); + + The parameters are passed in registers from userland: + r0: cl_args + r1: size + r2: func + r3: arg */ + +ENTRY(__clone3) + + /* Save args for the child. */ + mov r10, r0 /* cl_args */ + mov r11, r2 /* func */ + mov r12, r3 /* args */ + + /* Sanity check args. */ + breq r10, 0, L (__sys_err) /* No NULL cl_args pointer. */ + breq r11, 0, L (__sys_err) /* No NULL function pointer. */ + + /* Do the system call, the kernel expects: + r8: system call number + r0: cl_args + r1: size */ + mov r0, r10 + mov r8, __NR_clone3 + ARC_TRAP_INSN + + cmp r0, 0 + beq thread_start_clone3 /* Child returns. */ + blt L (__sys_err2) + j [blink] /* Parent returns. */ + +L (__sys_err): + mov r0, -EINVAL +L (__sys_err2): + b __syscall_error +PSEUDO_END (__clone3) + + + .align 4 + .type thread_start_clone3, %function +thread_start_clone3: + cfi_startproc + /* Terminate call stack by noting ra is undefined. */ + cfi_undefined (blink) + + /* Child jumps off to @fn with @arg as argument. */ + jl.d [r11] + mov r0, r12 + + /* exit() with result from @fn (already in r0). */ + mov r8, __NR_exit + ARC_TRAP_INSN + + /* In case it ever came back. */ + flag 1 + + cfi_endproc + .size thread_start_clone3, .-thread_start_clone3 + +libc_hidden_def (__clone3) +weak_alias (__clone3, clone3) diff --git a/sysdeps/unix/sysv/linux/arc/sysdep.h b/sysdeps/unix/sysv/linux/arc/sysdep.h index dd6fe73..88dc1df 100644 --- a/sysdeps/unix/sysv/linux/arc/sysdep.h +++ b/sysdeps/unix/sysv/linux/arc/sysdep.h @@ -141,6 +141,8 @@ hidden_proto (__syscall_error) # define ARC_TRAP_INSN "trap_s 0 \n\t" +# define HAVE_CLONE3_WRAPPER 1 + # undef INTERNAL_SYSCALL_NCS # define INTERNAL_SYSCALL_NCS(number, nr_args, args...) \ ({ \ |