ubuntu-linux-kernel/arch/arm/include/asm/syscall.h

114 lines
2.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Access to user system call parameters and results
*
* See asm-generic/syscall.h for descriptions of what we must do here.
*/
#ifndef _ASM_ARM_SYSCALL_H
#define _ASM_ARM_SYSCALL_H
#include <uapi/linux/audit.h> /* for AUDIT_ARCH_* */
#include <linux/elf.h> /* for ELF_EM */
#include <linux/err.h>
#include <linux/sched.h>
#include <asm/unistd.h>
#define NR_syscalls (__NR_syscalls)
extern const unsigned long sys_call_table[];
static inline int syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)
{
return task_thread_info(task)->syscall;
}
static inline void syscall_rollback(struct task_struct *task,
struct pt_regs *regs)
{
regs->ARM_r0 = regs->ARM_ORIG_r0;
}
static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
unsigned long error = regs->ARM_r0;
return IS_ERR_VALUE(error) ? error : 0;
}
static inline long syscall_get_return_value(struct task_struct *task,
struct pt_regs *regs)
{
return regs->ARM_r0;
}
static inline void syscall_set_return_value(struct task_struct *task,
struct pt_regs *regs,
int error, long val)
{
regs->ARM_r0 = (long) error ? error : val;
}
#define SYSCALL_MAX_ARGS 7
static inline void syscall_get_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
unsigned long *args)
{
if (n == 0)
return;
if (i + n > SYSCALL_MAX_ARGS) {
unsigned long *args_bad = args + SYSCALL_MAX_ARGS - i;
unsigned int n_bad = n + i - SYSCALL_MAX_ARGS;
pr_warn("%s called with max args %d, handling only %d\n",
__func__, i + n, SYSCALL_MAX_ARGS);
memset(args_bad, 0, n_bad * sizeof(args[0]));
n = SYSCALL_MAX_ARGS - i;
}
if (i == 0) {
args[0] = regs->ARM_ORIG_r0;
args++;
i++;
n--;
}
memcpy(args, &regs->ARM_r0 + 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)
{
if (n == 0)
return;
if (i + n > SYSCALL_MAX_ARGS) {
pr_warn("%s called with max args %d, handling only %d\n",
__func__, i + n, SYSCALL_MAX_ARGS);
n = SYSCALL_MAX_ARGS - i;
}
if (i == 0) {
regs->ARM_ORIG_r0 = args[0];
args++;
i++;
n--;
}
memcpy(&regs->ARM_r0 + i, args, n * sizeof(args[0]));
}
static inline int syscall_get_arch(void)
{
/* ARM tasks don't change audit architectures on the fly. */
return AUDIT_ARCH_ARM;
}
#endif /* _ASM_ARM_SYSCALL_H */