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/* Copyright (C) 1996-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ralf Baechle <ralf@linux-mips.org>, 1996.
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 <sys/asm.h>
#include <sysdep.h>
#define _ERRNO_H 1
#include <bits/errno.h>
#ifdef RESET_PID
#include <tls.h>
#endif
#define CLONE_VM 0x00000100
#define CLONE_THREAD 0x00010000
/* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg,
void *parent_tidptr, void *tls, void *child_tidptr) */
.text
.set nomips16
#if _MIPS_SIM == _ABIO32
# define EXTRA_LOCALS 1
#else
# define EXTRA_LOCALS 0
#endif
LOCALSZ= 4
FRAMESZ= (((NARGSAVE+LOCALSZ)*SZREG)+ALSZ)&ALMASK
GPOFF= FRAMESZ-(1*SZREG)
NESTED(__clone,4*SZREG,sp)
#ifdef __PIC__
SETUP_GP
#endif
PTR_SUBU sp, FRAMESZ
cfi_adjust_cfa_offset (FRAMESZ)
SETUP_GP64_STACK (GPOFF, __clone)
#ifdef __PIC__
SAVE_GP (GPOFF)
#endif
#ifdef PROF
.set noat
move $1,ra
jal _mcount
.set at
#endif
/* Sanity check arguments. */
li v0,EINVAL
beqz a0,L(error) /* No NULL function pointers. */
beqz a1,L(error) /* No NULL stack pointers. */
PTR_SUBU a1,32 /* Reserve argument save space. */
PTR_S a0,0(a1) /* Save function pointer. */
PTR_S a3,PTRSIZE(a1) /* Save argument pointer. */
#ifdef RESET_PID
LONG_S a2,(PTRSIZE*2)(a1) /* Save clone flags. */
#endif
move a0,a2
/* Shuffle in the last three arguments - arguments 5, 6, and 7 to
this function, but arguments 3, 4, and 5 to the syscall. */
#if _MIPS_SIM == _ABIO32
PTR_L a2,(FRAMESZ+PTRSIZE+PTRSIZE+16)(sp)
PTR_S a2,16(sp)
PTR_L a2,(FRAMESZ+16)(sp)
PTR_L a3,(FRAMESZ+PTRSIZE+16)(sp)
#else
move a2,a4
move a3,a5
move a4,a6
#endif
/* Do the system call */
li v0,__NR_clone
cfi_endproc
syscall
bnez a3,L(error)
beqz v0,L(thread_start)
/* Successful return from the parent */
cfi_startproc
cfi_adjust_cfa_offset (FRAMESZ)
SETUP_GP64_STACK_CFI (GPOFF)
cfi_remember_state
RESTORE_GP64_STACK
PTR_ADDU sp, FRAMESZ
cfi_adjust_cfa_offset (-FRAMESZ)
ret
/* Something bad happened -- no child created */
L(error):
cfi_restore_state
#ifdef __PIC__
PTR_LA t9,__syscall_error
RESTORE_GP64_STACK
PTR_ADDU sp, FRAMESZ
cfi_adjust_cfa_offset (-FRAMESZ)
jr t9
#else
RESTORE_GP64_STACK
PTR_ADDU sp, FRAMESZ
cfi_adjust_cfa_offset (-FRAMESZ)
j __syscall_error
#endif
END(__clone)
/* Load up the arguments to the function. Put this block of code in
its own function so that we can terminate the stack trace with our
debug info. */
ENTRY(__thread_start)
L(thread_start):
cfi_undefined ($31)
/* cp is already loaded. */
SAVE_GP (GPOFF)
/* The stackframe has been created on entry of clone(). */
#ifdef RESET_PID
/* Check and see if we need to reset the PID. */
LONG_L a0,(PTRSIZE*2)(sp)
and a1,a0,CLONE_THREAD
beqz a1,L(restore_pid)
L(donepid):
#endif
/* Restore the arg for user's function. */
PTR_L t9,0(sp) /* Function pointer. */
PTR_L a0,PTRSIZE(sp) /* Argument pointer. */
/* Call the user's function. */
jal t9
/* Call _exit rather than doing it inline for breakpoint purposes. */
move a0,v0
#ifdef __PIC__
PTR_LA t9,_exit
jalr t9
#else
jal _exit
#endif
#ifdef RESET_PID
L(restore_pid):
and a1,a0,CLONE_VM
li v0,-1
bnez a1,L(gotpid)
li v0,__NR_getpid
syscall
L(gotpid):
READ_THREAD_POINTER(v1)
INT_S v0,PID_OFFSET(v1)
INT_S v0,TID_OFFSET(v1)
b L(donepid)
#endif
END(__thread_start)
weak_alias (__clone, clone)
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