/*
   * arch/score/kernel/syscall.c
   *
   * Score Processor version.
   *
   * Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
   *  Chen Liqin <liqin.chen@sunplusct.com>
   *  Lennox Wu <lennox.wu@sunplusct.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, see the file COPYING, or write
   * to the Free Software Foundation, Inc.,
   * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
   */
  
  #include <linux/file.h>
  #include <linux/fs.h>

  #include <linux/mm.h>

  #include <linux/mman.h>
  #include <linux/module.h>

  #include <linux/slab.h>

  #include <linux/unistd.h>

  #include <linux/syscalls.h>
  #include <asm/syscalls.h>

  asmlinkage long 

  sys_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
  	  unsigned long flags, unsigned long fd, unsigned long pgoff)
  {

  	return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);

  }

  asmlinkage long
  sys_mmap(unsigned long addr, unsigned long len, unsigned long prot,

  	unsigned long flags, unsigned long fd, off_t offset)

  {

  	if (unlikely(offset & ~PAGE_MASK))
  		return -EINVAL;
  	return sys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);

  }
  
  asmlinkage long
  score_fork(struct pt_regs *regs)
  {
  	return do_fork(SIGCHLD, regs->regs[0], regs, 0, NULL, NULL);
  }

  /*
   * Clone a task - this clones the calling program thread.
   * This is called indirectly via a small wrapper
   */

  asmlinkage long
  score_clone(struct pt_regs *regs)

  {
  	unsigned long clone_flags;
  	unsigned long newsp;
  	int __user *parent_tidptr, *child_tidptr;
  
  	clone_flags = regs->regs[4];
  	newsp = regs->regs[5];
  	if (!newsp)
  		newsp = regs->regs[0];
  	parent_tidptr = (int __user *)regs->regs[6];

  	child_tidptr = (int __user *)regs->regs[8];

  
  	return do_fork(clone_flags, newsp, regs, 0,
  			parent_tidptr, child_tidptr);
  }

  asmlinkage long
  score_vfork(struct pt_regs *regs)
  {
  	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD,
  			regs->regs[0], regs, 0, NULL, NULL);
  }

  /*
   * sys_execve() executes a new program.
   * This is called indirectly via a small wrapper
   */

  asmlinkage long
  score_execve(struct pt_regs *regs)

  {
  	int error;
  	char *filename;

  	filename = getname((char __user*)regs->regs[4]);

  	error = PTR_ERR(filename);
  	if (IS_ERR(filename))
  		return error;

  	error = do_execve(filename,
  			  (const char __user *const __user *)regs->regs[5],
  			  (const char __user *const __user *)regs->regs[6],
  			  regs);

  
  	putname(filename);
  	return error;
  }
  
  /*

   * Do a system call from kernel instead of calling sys_execve so we
   * end up with proper pt_regs.
   */

  int kernel_execve(const char *filename,
  		  const char *const argv[],
  		  const char *const envp[])

  {
  	register unsigned long __r4 asm("r4") = (unsigned long) filename;
  	register unsigned long __r5 asm("r5") = (unsigned long) argv;
  	register unsigned long __r6 asm("r6") = (unsigned long) envp;
  	register unsigned long __r7 asm("r7");
  
  	__asm__ __volatile__ ("	
  "
  		"ldi	r27, %5		
  "
  		"syscall		
  "
  		"mv	%0, r4		
  "
  		"mv	%1, r7		
  "
  		: "=&r" (__r4), "=r" (__r7)
  		: "r" (__r4), "r" (__r5), "r" (__r6), "i" (__NR_execve)
  		: "r8", "r9", "r10", "r11", "r22", "r23", "r24", "r25",
  		  "r26", "r27", "memory");
  
  	if (__r7 == 0)
  		return __r4;
  
  	return -__r4;
  }