1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Access to user system call parameters and results
5 * Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved.
7 * See asm-generic/syscall.h for descriptions of what we must do here.
10 #ifndef _ASM_X86_SYSCALL_H
11 #define _ASM_X86_SYSCALL_H
13 #include <uapi/linux/audit.h>
14 #include <linux/sched.h>
15 #include <linux/err.h>
16 #include <asm/asm-offsets.h> /* For NR_syscalls */
17 #include <asm/thread_info.h> /* for TS_COMPAT */
18 #include <asm/unistd.h>
21 typedef asmlinkage long (*sys_call_ptr_t)(const struct pt_regs *);
23 typedef asmlinkage long (*sys_call_ptr_t)(unsigned long, unsigned long,
24 unsigned long, unsigned long,
25 unsigned long, unsigned long);
26 #endif /* CONFIG_X86_64 */
27 extern const sys_call_ptr_t sys_call_table[];
29 #if defined(CONFIG_X86_32)
30 #define ia32_sys_call_table sys_call_table
31 #define __NR_syscall_compat_max __NR_syscall_max
32 #define IA32_NR_syscalls NR_syscalls
35 #if defined(CONFIG_IA32_EMULATION)
36 extern const sys_call_ptr_t ia32_sys_call_table[];
39 #ifdef CONFIG_X86_X32_ABI
40 extern const sys_call_ptr_t x32_sys_call_table[];
44 * Only the low 32 bits of orig_ax are meaningful, so we return int.
45 * This importantly ignores the high bits on 64-bit, so comparisons
46 * sign-extend the low 32 bits.
48 static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
53 static inline void syscall_rollback(struct task_struct *task,
56 regs->ax = regs->orig_ax;
59 static inline long syscall_get_error(struct task_struct *task,
62 unsigned long error = regs->ax;
63 #ifdef CONFIG_IA32_EMULATION
65 * TS_COMPAT is set for 32-bit syscall entries and then
66 * remains set until we return to user mode.
68 if (task->thread_info.status & (TS_COMPAT|TS_I386_REGS_POKED))
70 * Sign-extend the value so (int)-EFOO becomes (long)-EFOO
71 * and will match correctly in comparisons.
73 error = (long) (int) error;
75 return IS_ERR_VALUE(error) ? error : 0;
78 static inline long syscall_get_return_value(struct task_struct *task,
84 static inline void syscall_set_return_value(struct task_struct *task,
88 regs->ax = (long) error ?: val;
93 static inline void syscall_get_arguments(struct task_struct *task,
97 memcpy(args, ®s->bx, 6 * sizeof(args[0]));
100 static inline void syscall_set_arguments(struct task_struct *task,
101 struct pt_regs *regs,
102 unsigned int i, unsigned int n,
103 const unsigned long *args)
106 memcpy(®s->bx + i, args, n * sizeof(args[0]));
109 static inline int syscall_get_arch(struct task_struct *task)
111 return AUDIT_ARCH_I386;
114 #else /* CONFIG_X86_64 */
116 static inline void syscall_get_arguments(struct task_struct *task,
117 struct pt_regs *regs,
120 # ifdef CONFIG_IA32_EMULATION
121 if (task->thread_info.status & TS_COMPAT) {
140 static inline void syscall_set_arguments(struct task_struct *task,
141 struct pt_regs *regs,
142 const unsigned long *args)
144 # ifdef CONFIG_IA32_EMULATION
145 if (task->thread_info.status & TS_COMPAT) {
164 static inline int syscall_get_arch(struct task_struct *task)
166 /* x32 tasks should be considered AUDIT_ARCH_X86_64. */
167 return (IS_ENABLED(CONFIG_IA32_EMULATION) &&
168 task->thread_info.status & TS_COMPAT)
169 ? AUDIT_ARCH_I386 : AUDIT_ARCH_X86_64;
171 #endif /* CONFIG_X86_32 */
173 #endif /* _ASM_X86_SYSCALL_H */