2 * Copyright (C) 2012 ARM Ltd.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License
14 * along with this program. If not, see <http://www.gnu.org/licenses/>.
16 #ifndef __ASM_SYSCALL_H
17 #define __ASM_SYSCALL_H
19 #include <uapi/linux/audit.h>
20 #include <linux/compat.h>
21 #include <linux/err.h>
23 typedef long (*syscall_fn_t)(const struct pt_regs *regs);
25 extern const syscall_fn_t sys_call_table[];
28 extern const syscall_fn_t compat_sys_call_table[];
31 static inline int syscall_get_nr(struct task_struct *task,
34 return regs->syscallno;
37 static inline void syscall_rollback(struct task_struct *task,
40 regs->regs[0] = regs->orig_x0;
44 static inline long syscall_get_error(struct task_struct *task,
47 unsigned long error = regs->regs[0];
49 if (is_compat_thread(task_thread_info(task)))
50 error = sign_extend64(error, 31);
52 return IS_ERR_VALUE(error) ? error : 0;
55 static inline long syscall_get_return_value(struct task_struct *task,
61 static inline void syscall_set_return_value(struct task_struct *task,
68 if (is_compat_thread(task_thread_info(task)))
69 val = lower_32_bits(val);
74 #define SYSCALL_MAX_ARGS 6
76 static inline void syscall_get_arguments(struct task_struct *task,
78 unsigned int i, unsigned int n,
84 if (i + n > SYSCALL_MAX_ARGS) {
85 unsigned long *args_bad = args + SYSCALL_MAX_ARGS - i;
86 unsigned int n_bad = n + i - SYSCALL_MAX_ARGS;
87 pr_warning("%s called with max args %d, handling only %d\n",
88 __func__, i + n, SYSCALL_MAX_ARGS);
89 memset(args_bad, 0, n_bad * sizeof(args[0]));
93 args[0] = regs->orig_x0;
99 memcpy(args, ®s->regs[i], n * sizeof(args[0]));
102 static inline void syscall_set_arguments(struct task_struct *task,
103 struct pt_regs *regs,
104 unsigned int i, unsigned int n,
105 const unsigned long *args)
110 if (i + n > SYSCALL_MAX_ARGS) {
111 pr_warning("%s called with max args %d, handling only %d\n",
112 __func__, i + n, SYSCALL_MAX_ARGS);
113 n = SYSCALL_MAX_ARGS - i;
117 regs->orig_x0 = args[0];
123 memcpy(®s->regs[i], args, n * sizeof(args[0]));
127 * We don't care about endianness (__AUDIT_ARCH_LE bit) here because
128 * AArch64 has the same system calls both on little- and big- endian.
130 static inline int syscall_get_arch(void)
132 if (is_compat_task())
133 return AUDIT_ARCH_ARM;
135 return AUDIT_ARCH_AARCH64;
138 #endif /* __ASM_SYSCALL_H */