mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-21 04:31:04 +08:00
144 lines
3.3 KiB
ArmAsm
144 lines
3.3 KiB
ArmAsm
/* Copyright (C) 1996-2013 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Richard Henderson <rth@tamu.edu>, 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 <sysdep.h>
|
|
#define _ERRNO_H 1
|
|
#include <bits/errno.h>
|
|
|
|
#define CLONE_VM 0x00000100
|
|
#define CLONE_THREAD 0x00010000
|
|
|
|
/* int clone(int (*fn)(void *arg), void *child_stack, int flags,
|
|
void *arg, pid_t *ptid, void *tls, pid_t *ctid);
|
|
|
|
Note that everything past ARG is technically optional, based
|
|
on FLAGS, and that CTID is arg 7, and thus is on the stack.
|
|
However, since a load from top-of-stack better be legal always,
|
|
we don't bother checking FLAGS. */
|
|
|
|
.text
|
|
.align 4
|
|
.globl __clone
|
|
.ent __clone
|
|
.usepv __clone, USEPV_PROF
|
|
|
|
cfi_startproc
|
|
__clone:
|
|
#ifdef PROF
|
|
ldgp gp,0(pv)
|
|
lda AT, _mcount
|
|
jsr AT, (AT), _mcount
|
|
#endif
|
|
|
|
/* Sanity check arguments. */
|
|
ldiq v0, EINVAL
|
|
beq a0, SYSCALL_ERROR_LABEL /* no NULL function pointers */
|
|
beq a1, SYSCALL_ERROR_LABEL /* no NULL stack pointers */
|
|
|
|
/* Save the fn ptr and arg on the new stack. */
|
|
subq a1, 32, a1
|
|
stq a0, 0(a1)
|
|
stq a3, 8(a1)
|
|
#ifdef RESET_PID
|
|
stq a2, 16(a1)
|
|
#endif
|
|
|
|
/* The syscall is of the form clone(flags, usp, ptid, ctid, tls).
|
|
Shift the flags, ptid, ctid, tls arguments into place; the
|
|
child_stack argument is already correct. */
|
|
mov a2, a0
|
|
mov a4, a2
|
|
ldq a3, 0(sp)
|
|
mov a5, a4
|
|
|
|
/* Do the system call. */
|
|
ldiq v0, __NR_clone
|
|
call_pal PAL_callsys
|
|
|
|
bne a3, SYSCALL_ERROR_LABEL
|
|
beq v0, thread_start
|
|
|
|
/* Successful return from the parent. */
|
|
ret
|
|
|
|
PSEUDO_END(__clone)
|
|
cfi_endproc
|
|
|
|
/* 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. */
|
|
|
|
.ent thread_start
|
|
cfi_startproc
|
|
thread_start:
|
|
mov 0, fp
|
|
cfi_def_cfa_register(fp)
|
|
cfi_undefined(ra)
|
|
|
|
#ifdef RESET_PID
|
|
/* Check and see if we need to reset the PID. */
|
|
ldq t0, 16(sp)
|
|
lda t1, CLONE_THREAD
|
|
and t0, t1, t2
|
|
beq t2, 2f
|
|
1:
|
|
#endif
|
|
|
|
/* Load up the arguments. */
|
|
ldq pv, 0(sp)
|
|
ldq a0, 8(sp)
|
|
addq sp, 32, sp
|
|
|
|
/* Call the user's function. */
|
|
jsr ra, (pv)
|
|
ldgp gp, 0(ra)
|
|
|
|
/* Call _exit rather than doing it inline for breakpoint purposes. */
|
|
mov v0, a0
|
|
#ifdef PIC
|
|
bsr ra, HIDDEN_JUMPTARGET(_exit) !samegp
|
|
#else
|
|
jsr ra, HIDDEN_JUMPTARGET(_exit)
|
|
#endif
|
|
|
|
/* Die horribly. */
|
|
halt
|
|
|
|
#ifdef RESET_PID
|
|
2:
|
|
rduniq
|
|
lda t1, CLONE_VM
|
|
mov v0, s0
|
|
lda v0, -1
|
|
and t0, t1, t2
|
|
bne t2, 3f
|
|
lda v0, __NR_getxpid
|
|
callsys
|
|
3:
|
|
stl v0, PID_OFFSET(s0)
|
|
stl v0, TID_OFFSET(s0)
|
|
br 1b
|
|
#endif
|
|
cfi_endproc
|
|
.end thread_start
|
|
|
|
weak_alias (__clone, clone)
|