glibc/sysdeps/unix/sysv/linux/riscv/vfork.S
Joseph Myers 8cacbcf4a9 Fix RISC-V vfork build with Linux 5.3 kernel headers.
Building glibc for RISC-V with Linux 5.3 kernel headers fails because
<linux/sched.h>, included in vfork.S for CLONE_* constants, contains a
structure definition not safe for inclusion in assembly code.

All other architectures already avoid use of that header in vfork.S,
either defining the CLONE_* constants locally or embedding the
required values directly in the relevant instruction, where they
implement vfork using the clone syscall (see the implementations for
aarch64, ia64, mips and nios2).  This patch makes the RISC-V version
define the constants locally like the other architectures.

Tested build for all three RISC-V configurations in
build-many-glibcs.py with Linux 5.3 headers.

	* sysdeps/unix/sysv/linux/riscv/vfork.S: Do not include
	<linux/sched.h>.
	(CLONE_VM): New macro.
	(CLONE_VFORK): Likewise.
2019-09-18 13:22:24 +00:00

48 lines
1.4 KiB
ArmAsm

/* vfork for Linux, RISC-V version.
Copyright (C) 2005-2019 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/>. */
/* vfork() is just a special case of clone(). */
#include <sys/asm.h>
#include <sysdep.h>
#define __ASSEMBLY__
#include <asm/signal.h>
#define CLONE_VM 0x00000100 /* Set if VM shared between processes. */
#define CLONE_VFORK 0x00004000 /* Set if the parent wants the child to
wake it up on mm_release. */
.text
LEAF (__libc_vfork)
li a0, (CLONE_VFORK | CLONE_VM | SIGCHLD)
mv a1, sp
li a7, __NR_clone
scall
bltz a0, 1f
ret
1: j __syscall_error
END (__libc_vfork)
weak_alias (__libc_vfork, vfork)
strong_alias (__libc_vfork, __vfork)
libc_hidden_def (__vfork)