sys_arm.c
/*
* linux/arch/arm/kernel/sys_arm.c
*
* Copyright (C) People who wrote linux/arch/i386/kernel/sys_i386.c
* Copyright (C) 1995, 1996 Russell King.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This file contains various random system calls that
* have a non-standard calling sequence on the Linux/arm
* platform.
*/
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/stat.h>
#include <linux/syscalls.h>
#include <linux/mman.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/ipc.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
/* Fork a new task - this creates a new program thread.
* This is called indirectly via a small wrapper
*/
asmlinkage int sys_fork(struct pt_regs *regs)
{
#ifdef CONFIG_MMU
return do_fork(SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
#else
/* can not support in nommu mode */
return(-EINVAL);
#endif
}
/* Clone a task - this clones the calling program thread.
* This is called indirectly via a small wrapper
*/
asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
int __user *parent_tidptr, int tls_val,
int __user *child_tidptr, struct pt_regs *regs)
{
if (!newsp)
newsp = regs->ARM_sp;
return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr);
}
asmlinkage int sys_vfork(struct pt_regs *regs)
{
return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
}
/* sys_execve() executes a new program.
* This is called indirectly via a small wrapper
*/
asmlinkage int sys_execve(const char __user *filenamei,
const char __user *const __user *argv,
const char __user *const __user *envp, struct pt_regs *regs)
{
int error;
char * filename;
filename = getname(filenamei);
error = PTR_ERR(filename);
if (IS_ERR(filename))
goto out;
error = do_execve(filename, argv, envp, regs);
putname(filename);
out:
return error;
}
int kernel_execve(const char *filename,
const char *const argv[],
const char *const envp[])
{
struct pt_regs regs;
int ret;
memset(®s, 0, sizeof(struct pt_regs));
ret = do_execve(filename,
(const char __user *const __user *)argv,
(const char __user *const __user *)envp, ®s);
if (ret < 0)
goto out;
/*
* Save argc to the register structure for userspace.
*/
regs.ARM_r0 = ret;
/*
* We were successful. We won't be returning to our caller, but
* instead to user space by manipulating the kernel stack.
*/
asm( "add r0, %0, %1\n\t"
"mov r1, %2\n\t"
"mov r2, %3\n\t"
"bl memmove\n\t" /* copy regs to top of stack */
"mov r8, #0\n\t" /* not a syscall */
"mov r9, %0\n\t" /* thread structure */
"mov sp, r0\n\t" /* reposition stack pointer */
"b ret_to_user"
:
: "r" (current_thread_info()),
"Ir" (THREAD_START_SP - sizeof(regs)),
"r" (®s),
"Ir" (sizeof(regs))
: "r0", "r1", "r2", "r3", "ip", "lr", "memory");
out:
return ret;
}
EXPORT_SYMBOL(kernel_execve);
/*
* Since loff_t is a 64 bit type we avoid a lot of ABI hassle
* with a different argument ordering.
*/
asmlinkage long sys_arm_fadvise64_64(int fd, int advice,
loff_t offset, loff_t len)
{
return sys_fadvise64_64(fd, offset, len, advice);
}