x86/efi: Enforce CONFIG_RELOCATABLE for EFI boot stub
[linux/fpc-iii.git] / arch / x86 / include / asm / syscall.h
blobaea284b413122f14ccbf757fd5b114d6b12bb094
1 /*
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 <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 void (*sys_call_ptr_t)(void);
24 extern const sys_call_ptr_t sys_call_table[];
27 * Only the low 32 bits of orig_ax are meaningful, so we return int.
28 * This importantly ignores the high bits on 64-bit, so comparisons
29 * sign-extend the low 32 bits.
31 static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
33 return regs->orig_ax;
36 static inline void syscall_rollback(struct task_struct *task,
37 struct pt_regs *regs)
39 regs->ax = regs->orig_ax;
42 static inline long syscall_get_error(struct task_struct *task,
43 struct pt_regs *regs)
45 unsigned long error = regs->ax;
46 #ifdef CONFIG_IA32_EMULATION
48 * TS_COMPAT is set for 32-bit syscall entries and then
49 * remains set until we return to user mode.
51 if (task_thread_info(task)->status & TS_COMPAT)
53 * Sign-extend the value so (int)-EFOO becomes (long)-EFOO
54 * and will match correctly in comparisons.
56 error = (long) (int) error;
57 #endif
58 return IS_ERR_VALUE(error) ? error : 0;
61 static inline long syscall_get_return_value(struct task_struct *task,
62 struct pt_regs *regs)
64 return regs->ax;
67 static inline void syscall_set_return_value(struct task_struct *task,
68 struct pt_regs *regs,
69 int error, long val)
71 regs->ax = (long) error ?: val;
74 #ifdef CONFIG_X86_32
76 static inline void syscall_get_arguments(struct task_struct *task,
77 struct pt_regs *regs,
78 unsigned int i, unsigned int n,
79 unsigned long *args)
81 BUG_ON(i + n > 6);
82 memcpy(args, &regs->bx + i, n * sizeof(args[0]));
85 static inline void syscall_set_arguments(struct task_struct *task,
86 struct pt_regs *regs,
87 unsigned int i, unsigned int n,
88 const unsigned long *args)
90 BUG_ON(i + n > 6);
91 memcpy(&regs->bx + i, args, n * sizeof(args[0]));
94 static inline int syscall_get_arch(struct task_struct *task,
95 struct pt_regs *regs)
97 return AUDIT_ARCH_I386;
100 #else /* CONFIG_X86_64 */
102 static inline void syscall_get_arguments(struct task_struct *task,
103 struct pt_regs *regs,
104 unsigned int i, unsigned int n,
105 unsigned long *args)
107 # ifdef CONFIG_IA32_EMULATION
108 if (task_thread_info(task)->status & TS_COMPAT)
109 switch (i) {
110 case 0:
111 if (!n--) break;
112 *args++ = regs->bx;
113 case 1:
114 if (!n--) break;
115 *args++ = regs->cx;
116 case 2:
117 if (!n--) break;
118 *args++ = regs->dx;
119 case 3:
120 if (!n--) break;
121 *args++ = regs->si;
122 case 4:
123 if (!n--) break;
124 *args++ = regs->di;
125 case 5:
126 if (!n--) break;
127 *args++ = regs->bp;
128 case 6:
129 if (!n--) break;
130 default:
131 BUG();
132 break;
134 else
135 # endif
136 switch (i) {
137 case 0:
138 if (!n--) break;
139 *args++ = regs->di;
140 case 1:
141 if (!n--) break;
142 *args++ = regs->si;
143 case 2:
144 if (!n--) break;
145 *args++ = regs->dx;
146 case 3:
147 if (!n--) break;
148 *args++ = regs->r10;
149 case 4:
150 if (!n--) break;
151 *args++ = regs->r8;
152 case 5:
153 if (!n--) break;
154 *args++ = regs->r9;
155 case 6:
156 if (!n--) break;
157 default:
158 BUG();
159 break;
163 static inline void syscall_set_arguments(struct task_struct *task,
164 struct pt_regs *regs,
165 unsigned int i, unsigned int n,
166 const unsigned long *args)
168 # ifdef CONFIG_IA32_EMULATION
169 if (task_thread_info(task)->status & TS_COMPAT)
170 switch (i) {
171 case 0:
172 if (!n--) break;
173 regs->bx = *args++;
174 case 1:
175 if (!n--) break;
176 regs->cx = *args++;
177 case 2:
178 if (!n--) break;
179 regs->dx = *args++;
180 case 3:
181 if (!n--) break;
182 regs->si = *args++;
183 case 4:
184 if (!n--) break;
185 regs->di = *args++;
186 case 5:
187 if (!n--) break;
188 regs->bp = *args++;
189 case 6:
190 if (!n--) break;
191 default:
192 BUG();
193 break;
195 else
196 # endif
197 switch (i) {
198 case 0:
199 if (!n--) break;
200 regs->di = *args++;
201 case 1:
202 if (!n--) break;
203 regs->si = *args++;
204 case 2:
205 if (!n--) break;
206 regs->dx = *args++;
207 case 3:
208 if (!n--) break;
209 regs->r10 = *args++;
210 case 4:
211 if (!n--) break;
212 regs->r8 = *args++;
213 case 5:
214 if (!n--) break;
215 regs->r9 = *args++;
216 case 6:
217 if (!n--) break;
218 default:
219 BUG();
220 break;
224 static inline int syscall_get_arch(struct task_struct *task,
225 struct pt_regs *regs)
227 #ifdef CONFIG_IA32_EMULATION
229 * TS_COMPAT is set for 32-bit syscall entry and then
230 * remains set until we return to user mode.
232 * TIF_IA32 tasks should always have TS_COMPAT set at
233 * system call time.
235 * x32 tasks should be considered AUDIT_ARCH_X86_64.
237 if (task_thread_info(task)->status & TS_COMPAT)
238 return AUDIT_ARCH_I386;
239 #endif
240 /* Both x32 and x86_64 are considered "64-bit". */
241 return AUDIT_ARCH_X86_64;
243 #endif /* CONFIG_X86_32 */
245 #endif /* _ASM_X86_SYSCALL_H */