| /* Wrapper around clone system call. |
| Copyright (C) 1997-2018 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/>. */ |
| |
| #include <sysdep.h> |
| #define _ERRNO_H 1 |
| #include <bits/errno.h> |
| |
| /* This is the only really unusual system call in PPC linux, but not |
| because of any weirdness in the system call itself; because of |
| all the freaky stuff we have to do to make the call useful. */ |
| |
| /* int [r3] clone(int (*fn)(void *arg) [r3], void *child_stack [r4], |
| int flags [r5], void *arg [r6], void *parent_tid [r7], |
| void *tls [r8], void *child_tid [r9]); */ |
| |
| ENTRY (__clone) |
| |
| /* Check for child_stack == NULL || fn == NULL. */ |
| cmpwi cr0,r4,0 |
| cmpwi cr1,r3,0 |
| cror cr0*4+eq,cr1*4+eq,cr0*4+eq |
| beq- cr0,L(badargs) |
| |
| /* Set up stack frame for parent. */ |
| stwu r1,-32(r1) |
| cfi_adjust_cfa_offset (32) |
| stmw r28,16(r1) |
| |
| /* Set up stack frame for child. */ |
| clrrwi r4,r4,4 |
| li r0,0 |
| stwu r0,-16(r4) |
| |
| /* Save fn, args, stack across syscall. */ |
| mr r30,r3 /* Function in r30. */ |
| mr r28,r5 |
| mr r31,r6 /* Argument in r31. */ |
| |
| /* 'flags' argument is first parameter to clone syscall. (The other |
| argument is the stack pointer, already in r4.) */ |
| mr r3,r5 |
| |
| /* Move the parent_tid, child_tid and tls arguments. */ |
| mr r5,r7 |
| mr r6,r8 |
| mr r7,r9 |
| |
| /* End FDE now, because in the child the unwind info will be |
| wrong. */ |
| cfi_endproc |
| |
| /* Do the call. */ |
| DO_CALL(SYS_ify(clone)) |
| |
| /* Check for child process. */ |
| cmpwi cr1,r3,0 |
| crandc cr1*4+eq,cr1*4+eq,cr0*4+so |
| bne- cr1,L(parent) /* The '-' is to minimise the race. */ |
| |
| /* Call procedure. */ |
| mtctr r30 |
| mr r3,r31 |
| bctrl |
| DO_CALL(SYS_ify(exit)) |
| |
| L(parent): |
| /* Parent. Restore registers & return. */ |
| lmw r28,16(r1) |
| addi r1,r1,32 |
| bnslr+ |
| b __syscall_error@local |
| |
| L(badargs): |
| li r3,EINVAL |
| b __syscall_error@local |
| |
| cfi_startproc |
| END (__clone) |
| |
| libc_hidden_def (__clone) |
| weak_alias (__clone, clone) |
