/*
   *	Wrapper functions for 16bit uid back compatibility. All nicely tied
   *	together in the faint hope we can take the out in five years time.
   */
  
  #include <linux/mm.h>
  #include <linux/utsname.h>
  #include <linux/mman.h>
  #include <linux/smp_lock.h>
  #include <linux/notifier.h>
  #include <linux/reboot.h>
  #include <linux/prctl.h>

  #include <linux/capability.h>

  #include <linux/init.h>
  #include <linux/highuid.h>
  #include <linux/security.h>
  #include <linux/syscalls.h>
  
  #include <asm/uaccess.h>
  
  asmlinkage long sys_chown16(const char __user * filename, old_uid_t user, old_gid_t group)
  {

  	long ret = sys_chown(filename, low2highuid(user), low2highgid(group));
  	/* avoid REGPARM breakage on x86: */
  	prevent_tail_call(ret);
  	return ret;

  }
  
  asmlinkage long sys_lchown16(const char __user * filename, old_uid_t user, old_gid_t group)
  {

  	long ret = sys_lchown(filename, low2highuid(user), low2highgid(group));
  	/* avoid REGPARM breakage on x86: */
  	prevent_tail_call(ret);
  	return ret;

  }
  
  asmlinkage long sys_fchown16(unsigned int fd, old_uid_t user, old_gid_t group)
  {

  	long ret = sys_fchown(fd, low2highuid(user), low2highgid(group));
  	/* avoid REGPARM breakage on x86: */
  	prevent_tail_call(ret);
  	return ret;

  }
  
  asmlinkage long sys_setregid16(old_gid_t rgid, old_gid_t egid)
  {

  	long ret = sys_setregid(low2highgid(rgid), low2highgid(egid));
  	/* avoid REGPARM breakage on x86: */
  	prevent_tail_call(ret);
  	return ret;

  }
  
  asmlinkage long sys_setgid16(old_gid_t gid)
  {

  	long ret = sys_setgid(low2highgid(gid));
  	/* avoid REGPARM breakage on x86: */
  	prevent_tail_call(ret);
  	return ret;

  }
  
  asmlinkage long sys_setreuid16(old_uid_t ruid, old_uid_t euid)
  {

  	long ret = sys_setreuid(low2highuid(ruid), low2highuid(euid));
  	/* avoid REGPARM breakage on x86: */
  	prevent_tail_call(ret);
  	return ret;

  }
  
  asmlinkage long sys_setuid16(old_uid_t uid)
  {

  	long ret = sys_setuid(low2highuid(uid));
  	/* avoid REGPARM breakage on x86: */
  	prevent_tail_call(ret);
  	return ret;

  }
  
  asmlinkage long sys_setresuid16(old_uid_t ruid, old_uid_t euid, old_uid_t suid)
  {

  	long ret = sys_setresuid(low2highuid(ruid), low2highuid(euid),
  				 low2highuid(suid));
  	/* avoid REGPARM breakage on x86: */
  	prevent_tail_call(ret);
  	return ret;

  }
  
  asmlinkage long sys_getresuid16(old_uid_t __user *ruid, old_uid_t __user *euid, old_uid_t __user *suid)
  {
  	int retval;
  
  	if (!(retval = put_user(high2lowuid(current->uid), ruid)) &&
  	    !(retval = put_user(high2lowuid(current->euid), euid)))
  		retval = put_user(high2lowuid(current->suid), suid);
  
  	return retval;
  }
  
  asmlinkage long sys_setresgid16(old_gid_t rgid, old_gid_t egid, old_gid_t sgid)
  {

  	long ret = sys_setresgid(low2highgid(rgid), low2highgid(egid),
  				 low2highgid(sgid));
  	/* avoid REGPARM breakage on x86: */
  	prevent_tail_call(ret);
  	return ret;

  }
  
  asmlinkage long sys_getresgid16(old_gid_t __user *rgid, old_gid_t __user *egid, old_gid_t __user *sgid)
  {
  	int retval;
  
  	if (!(retval = put_user(high2lowgid(current->gid), rgid)) &&
  	    !(retval = put_user(high2lowgid(current->egid), egid)))
  		retval = put_user(high2lowgid(current->sgid), sgid);
  
  	return retval;
  }
  
  asmlinkage long sys_setfsuid16(old_uid_t uid)
  {

  	long ret = sys_setfsuid(low2highuid(uid));
  	/* avoid REGPARM breakage on x86: */
  	prevent_tail_call(ret);
  	return ret;

  }
  
  asmlinkage long sys_setfsgid16(old_gid_t gid)
  {

  	long ret = sys_setfsgid(low2highgid(gid));
  	/* avoid REGPARM breakage on x86: */
  	prevent_tail_call(ret);
  	return ret;

  }
  
  static int groups16_to_user(old_gid_t __user *grouplist,
      struct group_info *group_info)
  {
  	int i;
  	old_gid_t group;
  
  	for (i = 0; i < group_info->ngroups; i++) {
  		group = high2lowgid(GROUP_AT(group_info, i));
  		if (put_user(group, grouplist+i))
  			return -EFAULT;
  	}
  
  	return 0;
  }
  
  static int groups16_from_user(struct group_info *group_info,
      old_gid_t __user *grouplist)
  {
  	int i;
  	old_gid_t group;
  
  	for (i = 0; i < group_info->ngroups; i++) {
  		if (get_user(group, grouplist+i))
  			return  -EFAULT;
  		GROUP_AT(group_info, i) = low2highgid(group);
  	}
  
  	return 0;
  }
  
  asmlinkage long sys_getgroups16(int gidsetsize, old_gid_t __user *grouplist)
  {
  	int i = 0;
  
  	if (gidsetsize < 0)
  		return -EINVAL;
  
  	get_group_info(current->group_info);
  	i = current->group_info->ngroups;
  	if (gidsetsize) {
  		if (i > gidsetsize) {
  			i = -EINVAL;
  			goto out;
  		}
  		if (groups16_to_user(grouplist, current->group_info)) {
  			i = -EFAULT;
  			goto out;
  		}
  	}
  out:
  	put_group_info(current->group_info);
  	return i;
  }
  
  asmlinkage long sys_setgroups16(int gidsetsize, old_gid_t __user *grouplist)
  {
  	struct group_info *group_info;
  	int retval;
  
  	if (!capable(CAP_SETGID))
  		return -EPERM;
  	if ((unsigned)gidsetsize > NGROUPS_MAX)
  		return -EINVAL;
  
  	group_info = groups_alloc(gidsetsize);
  	if (!group_info)
  		return -ENOMEM;
  	retval = groups16_from_user(group_info, grouplist);
  	if (retval) {
  		put_group_info(group_info);
  		return retval;
  	}
  
  	retval = set_current_groups(group_info);
  	put_group_info(group_info);
  
  	return retval;
  }
  
  asmlinkage long sys_getuid16(void)
  {
  	return high2lowuid(current->uid);
  }
  
  asmlinkage long sys_geteuid16(void)
  {
  	return high2lowuid(current->euid);
  }
  
  asmlinkage long sys_getgid16(void)
  {
  	return high2lowgid(current->gid);
  }
  
  asmlinkage long sys_getegid16(void)
  {
  	return high2lowgid(current->egid);
  }