kernel-ark/include/asm-x86/syscall.h
Petr Tesarik 4ab4ba32aa x86, tracehook: clean up implementation of syscall_get_error()
The x86-tracehook code now contains this line in syscall_get_error():

	return error >= -4095L ? error : 0;

Hard-wiring a constant is not nice. Let's use the IS_ERR_VALUE macro
from linux/err.h instead.

Signed-off-by: Petr Tesarik <ptesarik@suse.cz>
Cc: utrace-devel@redhat.com
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-09-05 17:53:16 +02:00

212 lines
4.2 KiB
C

/*
* Access to user system call parameters and results
*
* Copyright (C) 2008 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License v.2.
*
* See asm-generic/syscall.h for descriptions of what we must do here.
*/
#ifndef _ASM_SYSCALL_H
#define _ASM_SYSCALL_H 1
#include <linux/sched.h>
#include <linux/err.h>
static inline long syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)
{
/*
* We always sign-extend a -1 value being set here,
* so this is always either -1L or a syscall number.
*/
return regs->orig_ax;
}
static inline void syscall_rollback(struct task_struct *task,
struct pt_regs *regs)
{
regs->ax = regs->orig_ax;
}
static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
unsigned long error = regs->ax;
#ifdef CONFIG_IA32_EMULATION
/*
* TS_COMPAT is set for 32-bit syscall entries and then
* remains set until we return to user mode.
*/
if (task_thread_info(task)->status & TS_COMPAT)
/*
* Sign-extend the value so (int)-EFOO becomes (long)-EFOO
* and will match correctly in comparisons.
*/
error = (long) (int) error;
#endif
return IS_ERR_VALUE(error) ? error : 0;
}
static inline long syscall_get_return_value(struct task_struct *task,
struct pt_regs *regs)
{
return regs->ax;
}
static inline void syscall_set_return_value(struct task_struct *task,
struct pt_regs *regs,
int error, long val)
{
regs->ax = (long) error ?: val;
}
#ifdef CONFIG_X86_32
static inline void syscall_get_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
unsigned long *args)
{
BUG_ON(i + n > 6);
memcpy(args, &regs->bx + i, n * sizeof(args[0]));
}
static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
const unsigned long *args)
{
BUG_ON(i + n > 6);
memcpy(&regs->bx + i, args, n * sizeof(args[0]));
}
#else /* CONFIG_X86_64 */
static inline void syscall_get_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
unsigned long *args)
{
# ifdef CONFIG_IA32_EMULATION
if (task_thread_info(task)->status & TS_COMPAT)
switch (i + n) {
case 6:
if (!n--) break;
*args++ = regs->bp;
case 5:
if (!n--) break;
*args++ = regs->di;
case 4:
if (!n--) break;
*args++ = regs->si;
case 3:
if (!n--) break;
*args++ = regs->dx;
case 2:
if (!n--) break;
*args++ = regs->cx;
case 1:
if (!n--) break;
*args++ = regs->bx;
case 0:
if (!n--) break;
default:
BUG();
break;
}
else
# endif
switch (i + n) {
case 6:
if (!n--) break;
*args++ = regs->r9;
case 5:
if (!n--) break;
*args++ = regs->r8;
case 4:
if (!n--) break;
*args++ = regs->r10;
case 3:
if (!n--) break;
*args++ = regs->dx;
case 2:
if (!n--) break;
*args++ = regs->si;
case 1:
if (!n--) break;
*args++ = regs->di;
case 0:
if (!n--) break;
default:
BUG();
break;
}
}
static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
const unsigned long *args)
{
# ifdef CONFIG_IA32_EMULATION
if (task_thread_info(task)->status & TS_COMPAT)
switch (i + n) {
case 6:
if (!n--) break;
regs->bp = *args++;
case 5:
if (!n--) break;
regs->di = *args++;
case 4:
if (!n--) break;
regs->si = *args++;
case 3:
if (!n--) break;
regs->dx = *args++;
case 2:
if (!n--) break;
regs->cx = *args++;
case 1:
if (!n--) break;
regs->bx = *args++;
case 0:
if (!n--) break;
default:
BUG();
}
else
# endif
switch (i + n) {
case 6:
if (!n--) break;
regs->r9 = *args++;
case 5:
if (!n--) break;
regs->r8 = *args++;
case 4:
if (!n--) break;
regs->r10 = *args++;
case 3:
if (!n--) break;
regs->dx = *args++;
case 2:
if (!n--) break;
regs->si = *args++;
case 1:
if (!n--) break;
regs->di = *args++;
case 0:
if (!n--) break;
default:
BUG();
}
}
#endif /* CONFIG_X86_32 */
#endif /* _ASM_SYSCALL_H */