linux/arch/tile/kernel/compat.c
Chris Metcalf ca768667d8 tile 32-bit big-endian: fix bugs in syscall argument order
The glibc __LONG_LONG_PAIR passes arguments in a different
order for BE platforms vs LE platforms.  Adjust the expectations
in the kernel 32-bit syscall routines for BE to match.

Signed-off-by: Chris Metcalf <cmetcalf@mellanox.com>
2016-06-15 15:31:01 -04:00

118 lines
3.7 KiB
C

/*
* Copyright 2010 Tilera Corporation. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program 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, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*/
/* Adjust unistd.h to provide 32-bit numbers and functions. */
#define __SYSCALL_COMPAT
#include <linux/compat.h>
#include <linux/syscalls.h>
#include <linux/kdev_t.h>
#include <linux/fs.h>
#include <linux/fcntl.h>
#include <linux/uaccess.h>
#include <linux/signal.h>
#include <asm/syscalls.h>
#include <asm/byteorder.h>
/*
* Syscalls that take 64-bit numbers traditionally take them in 32-bit
* "high" and "low" value parts on 32-bit architectures.
* In principle, one could imagine passing some register arguments as
* fully 64-bit on TILE-Gx in 32-bit mode, but it seems easier to
* adopt the usual convention.
*/
#ifdef __BIG_ENDIAN
#define SYSCALL_PAIR(name) u32, name ## _hi, u32, name ## _lo
#else
#define SYSCALL_PAIR(name) u32, name ## _lo, u32, name ## _hi
#endif
COMPAT_SYSCALL_DEFINE4(truncate64, char __user *, filename, u32, dummy,
SYSCALL_PAIR(length))
{
return sys_truncate(filename, ((loff_t)length_hi << 32) | length_lo);
}
COMPAT_SYSCALL_DEFINE4(ftruncate64, unsigned int, fd, u32, dummy,
SYSCALL_PAIR(length))
{
return sys_ftruncate(fd, ((loff_t)length_hi << 32) | length_lo);
}
COMPAT_SYSCALL_DEFINE6(pread64, unsigned int, fd, char __user *, ubuf,
size_t, count, u32, dummy, SYSCALL_PAIR(offset))
{
return sys_pread64(fd, ubuf, count,
((loff_t)offset_hi << 32) | offset_lo);
}
COMPAT_SYSCALL_DEFINE6(pwrite64, unsigned int, fd, char __user *, ubuf,
size_t, count, u32, dummy, SYSCALL_PAIR(offset))
{
return sys_pwrite64(fd, ubuf, count,
((loff_t)offset_hi << 32) | offset_lo);
}
COMPAT_SYSCALL_DEFINE6(sync_file_range2, int, fd, unsigned int, flags,
SYSCALL_PAIR(offset), SYSCALL_PAIR(nbytes))
{
return sys_sync_file_range(fd, ((loff_t)offset_hi << 32) | offset_lo,
((loff_t)nbytes_hi << 32) | nbytes_lo,
flags);
}
COMPAT_SYSCALL_DEFINE6(fallocate, int, fd, int, mode,
SYSCALL_PAIR(offset), SYSCALL_PAIR(len))
{
return sys_fallocate(fd, mode, ((loff_t)offset_hi << 32) | offset_lo,
((loff_t)len_hi << 32) | len_lo);
}
/*
* Avoid bug in generic sys_llseek() that specifies offset_high and
* offset_low as "unsigned long", thus making it possible to pass
* a sign-extended high 32 bits in offset_low.
* Note that we do not use SYSCALL_PAIR here since glibc passes the
* high and low parts explicitly in that order.
*/
COMPAT_SYSCALL_DEFINE5(llseek, unsigned int, fd, unsigned int, offset_high,
unsigned int, offset_low, loff_t __user *, result,
unsigned int, origin)
{
return sys_llseek(fd, offset_high, offset_low, result, origin);
}
/* Provide the compat syscall number to call mapping. */
#undef __SYSCALL
#define __SYSCALL(nr, call) [nr] = (call),
/* See comments in sys.c */
#define compat_sys_fadvise64_64 sys32_fadvise64_64
#define compat_sys_readahead sys32_readahead
#define sys_llseek compat_sys_llseek
/* Call the assembly trampolines where necessary. */
#define compat_sys_rt_sigreturn _compat_sys_rt_sigreturn
#define sys_clone _sys_clone
/*
* Note that we can't include <linux/unistd.h> here since the header
* guard will defeat us; <asm/unistd.h> checks for __SYSCALL as well.
*/
void *compat_sys_call_table[__NR_syscalls] = {
[0 ... __NR_syscalls-1] = sys_ni_syscall,
#include <asm/unistd.h>
};