mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-11 13:50:06 +00:00
99 lines
2.7 KiB
ArmAsm
99 lines
2.7 KiB
ArmAsm
/* Copyright (C) 1996-2013 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
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
/* clone() is even more special than fork() as it mucks with stacks
|
|
and invokes a function in the right context after its all over. */
|
|
|
|
#include <sysdep.h>
|
|
#define _ERRNO_H 1
|
|
#include <bits/errno.h>
|
|
|
|
#define CLONE_VM_BIT 8
|
|
#define CLONE_VM (1 << CLONE_VM_BIT)
|
|
|
|
#define CLONE_THREAD_BIT 16
|
|
#define CLONE_THREAD (1 << CLONE_THREAD_BIT)
|
|
|
|
/* int clone(int (*fn)(void *arg), x0
|
|
void *child_stack, x1
|
|
int flags, x2
|
|
void *arg, x3
|
|
pid_t *ptid, x4
|
|
struct user_desc *tls, x5
|
|
pid_t *ctid); x6
|
|
*/
|
|
.text
|
|
ENTRY(__clone)
|
|
/* Sanity check args. */
|
|
cbz x0, 1f
|
|
cbz x1, 1f
|
|
/* Insert the args onto the new stack. */
|
|
stp x0, x3, [x1, #-16]! /* Fn, arg. */
|
|
|
|
/* Do the system call. */
|
|
mov x0, x2 /* flags */
|
|
|
|
/* New sp is already in x1. */
|
|
mov x2, x4 /* ptid */
|
|
mov x3, x5 /* tls */
|
|
mov x4, x6 /* ctid */
|
|
|
|
#ifdef RESET_PID
|
|
/* We rely on the kernel preserving the argument regsiters across a
|
|
each system call so that we can inspect the flags against after
|
|
the clone call. */
|
|
mov x5, x0
|
|
#endif
|
|
|
|
mov x8, #SYS_ify(clone)
|
|
/* X0:flags, x1:newsp, x2:parenttidptr, x3:newtls, x4:childtid. */
|
|
svc 0x0
|
|
cmp x0, #0
|
|
beq 2f
|
|
blt C_SYMBOL_NAME(__syscall_error)
|
|
RET
|
|
1: mov x0, #-EINVAL
|
|
b syscall_error
|
|
|
|
2:
|
|
#ifdef RESET_PID
|
|
tbnz x5, #CLONE_THREAD_BIT, 3f
|
|
mov x0, #-1
|
|
tbnz x5, #CLONE_VM_BIT, 2f
|
|
mov x8, #SYS_ify(getpid)
|
|
svc 0x0
|
|
2:
|
|
mrs x1, tpidr_el0
|
|
sub x1, x1, #PTHREAD_SIZEOF
|
|
str w0, [x1, #PTHREAD_PID_OFFSET]
|
|
str w0, [x1, #PTHREAD_TID_OFFSET]
|
|
|
|
3:
|
|
#endif
|
|
/* Pick the function arg and call address from the stack and
|
|
execute. */
|
|
ldp x1, x0, [sp], #16
|
|
blr x1
|
|
|
|
/* We are done, pass the return value through x0. */
|
|
b HIDDEN_JUMPTARGET(_exit)
|
|
|
|
PSEUDO_END (__clone)
|
|
|
|
weak_alias (__clone, clone)
|