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This patch introduces the new syscall pipe2 which is like pipe but it also
takes an additional parameter which takes a flag value. This patch implements
the handling of O_CLOEXEC for the flag. I did not add support for the new
syscall for the architectures which have a special sys_pipe implementation. I
think the maintainers of those archs have the chance to go with the unified
implementation but that's up to them.
The implementation introduces do_pipe_flags. I did that instead of changing
all callers of do_pipe because some of the callers are written in assembler.
I would probably screw up changing the assembly code. To avoid breaking code
do_pipe is now a small wrapper around do_pipe_flags. Once all callers are
changed over to do_pipe_flags the old do_pipe function can be removed.
The following test must be adjusted for architectures other than x86 and
x86-64 and in case the syscall numbers changed.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>
#ifndef __NR_pipe2
# ifdef __x86_64__
# define __NR_pipe2 293
# elif defined __i386__
# define __NR_pipe2 331
# else
# error "need __NR_pipe2"
# endif
#endif
int
main (void)
{
int fd[2];
if (syscall (__NR_pipe2, fd, 0) != 0)
{
puts ("pipe2(0) failed");
return 1;
}
for (int i = 0; i < 2; ++i)
{
int coe = fcntl (fd[i], F_GETFD);
if (coe == -1)
{
puts ("fcntl failed");
return 1;
}
if (coe & FD_CLOEXEC)
{
printf ("pipe2(0) set close-on-exit for fd[%d]\n", i);
return 1;
}
}
close (fd[0]);
close (fd[1]);
if (syscall (__NR_pipe2, fd, O_CLOEXEC) != 0)
{
puts ("pipe2(O_CLOEXEC) failed");
return 1;
}
for (int i = 0; i < 2; ++i)
{
int coe = fcntl (fd[i], F_GETFD);
if (coe == -1)
{
puts ("fcntl failed");
return 1;
}
if ((coe & FD_CLOEXEC) == 0)
{
printf ("pipe2(O_CLOEXEC) does not set close-on-exit for fd[%d]\n", i);
return 1;
}
}
close (fd[0]);
close (fd[1]);
puts ("OK");
return 0;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Davide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
101 lines
2.3 KiB
C
101 lines
2.3 KiB
C
/*
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* arch/xtensa/kernel/syscall.c
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (C) 2001 - 2005 Tensilica Inc.
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* Copyright (C) 2000 Silicon Graphics, Inc.
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* Copyright (C) 1995 - 2000 by Ralf Baechle
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*
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* Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
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* Marc Gauthier <marc@tensilica.com, marc@alumni.uwaterloo.ca>
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* Chris Zankel <chris@zankel.net>
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* Kevin Chea
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*
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*/
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#include <asm/uaccess.h>
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#include <asm/syscall.h>
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#include <asm/unistd.h>
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#include <linux/linkage.h>
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#include <linux/stringify.h>
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#include <linux/errno.h>
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#include <linux/syscalls.h>
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#include <linux/file.h>
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#include <linux/fs.h>
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#include <linux/mman.h>
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#include <linux/shm.h>
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typedef void (*syscall_t)(void);
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syscall_t sys_call_table[__NR_syscall_count] /* FIXME __cacheline_aligned */= {
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[0 ... __NR_syscall_count - 1] = (syscall_t)&sys_ni_syscall,
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#undef __SYSCALL
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#define __SYSCALL(nr,symbol,nargs) [ nr ] = (syscall_t)symbol,
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#undef _XTENSA_UNISTD_H
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#undef __KERNEL_SYSCALLS__
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#include <asm/unistd.h>
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};
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/*
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* xtensa_pipe() is the normal C calling standard for creating a pipe. It's not
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* the way unix traditional does this, though.
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*/
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asmlinkage long xtensa_pipe(int __user *userfds)
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{
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int fd[2];
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int error;
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error = do_pipe_flags(fd, 0);
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if (!error) {
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if (copy_to_user(userfds, fd, 2 * sizeof(int)))
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error = -EFAULT;
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}
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return error;
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}
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asmlinkage long xtensa_mmap2(unsigned long addr, unsigned long len,
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unsigned long prot, unsigned long flags,
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unsigned long fd, unsigned long pgoff)
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{
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int error = -EBADF;
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struct file * file = NULL;
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flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
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if (!(flags & MAP_ANONYMOUS)) {
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file = fget(fd);
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if (!file)
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goto out;
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}
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down_write(¤t->mm->mmap_sem);
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error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
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up_write(¤t->mm->mmap_sem);
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if (file)
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fput(file);
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out:
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return error;
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}
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asmlinkage long xtensa_shmat(int shmid, char __user *shmaddr, int shmflg)
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{
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unsigned long ret;
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long err;
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err = do_shmat(shmid, shmaddr, shmflg, &ret);
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if (err)
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return err;
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return (long)ret;
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}
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asmlinkage long xtensa_fadvise64_64(int fd, int advice, unsigned long long offset, unsigned long long len)
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{
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return sys_fadvise64_64(fd, offset, len, advice);
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}
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