glibc/sysdeps/unix/sysv/linux/microblaze/clone.S

74 lines
2.1 KiB
ArmAsm

/* Copyright (C) 1996-2020 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/>. */
/* 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>
/* int clone (int (*fn)(void *arg), void *child_stack, int flags, void *arg,
pid_t *ptid, struct user_desc *tls, pid_t *ctid);
INCOMING: r5 (fn), r6 (child_stack), r7 (flags), r8 (arg), r9 (ptid)
r10 (tls), 28 (r1) ctid
OUTGOING:
linux: arch/microblaze/entry.S: sys_clone expects
r5 (flags) r6 (child stack) r7 (stack_size) r8 (ptid)r9 (ctid)
r10 (tls)
*/
.text
ENTRY (__clone)
addik r3,r0,-EINVAL
beqi r5,SYSCALL_ERROR_LABEL ; // Invalid func
beqi r6,SYSCALL_ERROR_LABEL ; // Invalid stack
addik r6,r6,-8
swi r5,r6,0 ; // Push fn onto child's stack
swi r8,r6,4 ; // Push arg for child
addk r5,r0,r7 ; // flags for clone() syscall
addk r7,r0,r0
addk r8,r0,r9 ; // parent tid ptr
lwi r9,r1,28 ; // child tid ptr
addik r12,r0,SYS_ify(clone)
brki r14,8
addk r0,r0,r0
addik r4,r0,-4095
cmpu r4,r4,r3
bgei r4,SYSCALL_ERROR_LABEL
beqi r3,L(thread_start)
rtsd r15,8
nop
L(thread_start):
lwi r12,r1,0 ; // fn
lwi r5,r1,4 ; // arg
brald r15,r12
nop
addk r5,r0,r3
addik r12,r0,SYS_ify(exit)
brki r14,8
nop
PSEUDO_END(__clone)
libc_hidden_def (__clone)
weak_alias (__clone,clone)