2 * Access to user system call parameters and results
4 * Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved.
6 * This copyrighted material is made available to anyone wishing to use,
7 * modify, copy, or redistribute it subject to the terms and conditions
8 * of the GNU General Public License v.2.
10 * See asm-generic/syscall.h for descriptions of what we must do here.
13 #ifndef _ASM_X86_SYSCALL_H
14 #define _ASM_X86_SYSCALL_H
16 #include <uapi/linux/audit.h>
17 #include <linux/sched.h>
18 #include <linux/err.h>
19 #include <asm/asm-offsets.h> /* For NR_syscalls */
20 #include <asm/thread_info.h> /* for TS_COMPAT */
21 #include <asm/unistd.h>
23 typedef asmlinkage
long (*sys_call_ptr_t
)(unsigned long, unsigned long,
24 unsigned long, unsigned long,
25 unsigned long, unsigned long);
26 extern const sys_call_ptr_t sys_call_table
[];
28 #if defined(CONFIG_X86_32)
29 #define ia32_sys_call_table sys_call_table
30 #define __NR_syscall_compat_max __NR_syscall_max
31 #define IA32_NR_syscalls NR_syscalls
34 #if defined(CONFIG_IA32_EMULATION)
35 extern const sys_call_ptr_t ia32_sys_call_table
[];
39 * Only the low 32 bits of orig_ax are meaningful, so we return int.
40 * This importantly ignores the high bits on 64-bit, so comparisons
41 * sign-extend the low 32 bits.
43 static inline int syscall_get_nr(struct task_struct
*task
, struct pt_regs
*regs
)
48 static inline void syscall_rollback(struct task_struct
*task
,
51 regs
->ax
= regs
->orig_ax
;
54 static inline long syscall_get_error(struct task_struct
*task
,
57 unsigned long error
= regs
->ax
;
58 #ifdef CONFIG_IA32_EMULATION
60 * TS_COMPAT is set for 32-bit syscall entries and then
61 * remains set until we return to user mode.
63 if (task_thread_info(task
)->status
& TS_COMPAT
)
65 * Sign-extend the value so (int)-EFOO becomes (long)-EFOO
66 * and will match correctly in comparisons.
68 error
= (long) (int) error
;
70 return IS_ERR_VALUE(error
) ? error
: 0;
73 static inline long syscall_get_return_value(struct task_struct
*task
,
79 static inline void syscall_set_return_value(struct task_struct
*task
,
83 regs
->ax
= (long) error
?: val
;
88 static inline void syscall_get_arguments(struct task_struct
*task
,
90 unsigned int i
, unsigned int n
,
94 memcpy(args
, ®s
->bx
+ i
, n
* sizeof(args
[0]));
97 static inline void syscall_set_arguments(struct task_struct
*task
,
99 unsigned int i
, unsigned int n
,
100 const unsigned long *args
)
103 memcpy(®s
->bx
+ i
, args
, n
* sizeof(args
[0]));
106 static inline int syscall_get_arch(void)
108 return AUDIT_ARCH_I386
;
111 #else /* CONFIG_X86_64 */
113 static inline void syscall_get_arguments(struct task_struct
*task
,
114 struct pt_regs
*regs
,
115 unsigned int i
, unsigned int n
,
118 # ifdef CONFIG_IA32_EMULATION
119 if (task_thread_info(task
)->status
& TS_COMPAT
)
174 static inline void syscall_set_arguments(struct task_struct
*task
,
175 struct pt_regs
*regs
,
176 unsigned int i
, unsigned int n
,
177 const unsigned long *args
)
179 # ifdef CONFIG_IA32_EMULATION
180 if (task_thread_info(task
)->status
& TS_COMPAT
)
235 static inline int syscall_get_arch(void)
237 #ifdef CONFIG_IA32_EMULATION
239 * TS_COMPAT is set for 32-bit syscall entry and then
240 * remains set until we return to user mode.
242 * TIF_IA32 tasks should always have TS_COMPAT set at
245 * x32 tasks should be considered AUDIT_ARCH_X86_64.
247 if (task_thread_info(current
)->status
& TS_COMPAT
)
248 return AUDIT_ARCH_I386
;
250 /* Both x32 and x86_64 are considered "64-bit". */
251 return AUDIT_ARCH_X86_64
;
253 #endif /* CONFIG_X86_32 */
255 #endif /* _ASM_X86_SYSCALL_H */