/*
   * Pioctl operations for Coda.

   * Original version: (C) 1996 Peter Braam

   * Rewritten for Linux 2.1: (C) 1997 Carnegie Mellon University
   *
   * Carnegie Mellon encourages users of this code to contribute improvements
   * to the Coda project. Contact Peter Braam <coda@cs.cmu.edu>.
   */
  
  #include <linux/types.h>
  #include <linux/kernel.h>
  #include <linux/time.h>
  #include <linux/fs.h>
  #include <linux/stat.h>
  #include <linux/errno.h>
  #include <linux/string.h>
  #include <linux/namei.h>
  #include <linux/module.h>
  #include <asm/uaccess.h>
  
  #include <linux/coda.h>

  #include <linux/coda_psdev.h>

  #include "coda_linux.h"

  /* pioctl ops */

  static int coda_ioctl_permission(struct inode *inode, int mask, unsigned int flags);

  static long coda_pioctl(struct file *filp, unsigned int cmd,
  			unsigned long user_data);

  
  /* exported from this file */

  const struct inode_operations coda_ioctl_inode_operations = {

  	.permission	= coda_ioctl_permission,
  	.setattr	= coda_setattr,
  };

  const struct file_operations coda_ioctl_operations = {

  	.owner		= THIS_MODULE,

  	.unlocked_ioctl	= coda_pioctl,

  	.llseek		= noop_llseek,

  };
  
  /* the coda pioctl inode ops */

  static int coda_ioctl_permission(struct inode *inode, int mask, unsigned int flags)

  {

  	if (flags & IPERM_FLAG_RCU)
  		return -ECHILD;

  	return (mask & MAY_EXEC) ? -EACCES : 0;

  }

  static long coda_pioctl(struct file *filp, unsigned int cmd,
  			unsigned long user_data)

  {

  	struct path path;

  	int error;

  	struct PioctlData data;

  	struct inode *inode = filp->f_dentry->d_inode;

  	struct inode *target_inode = NULL;
  	struct coda_inode_info *cnp;

  	/* get the Pioctl data arguments from user space */

  	if (copy_from_user(&data, (void __user *)user_data, sizeof(data)))
  		return -EINVAL;

  
  	/*
  	 * Look up the pathname. Note that the pathname is in
  	 * user memory, and namei takes care of this
  	 */

  	if (data.follow)

  		error = user_path(data.path, &path);

  	else

  		error = user_lpath(data.path, &path);

  
  	if (error)

  		return error;
  
  	target_inode = path.dentry->d_inode;

  	/* return if it is not a Coda inode */

  	if (target_inode->i_sb != inode->i_sb) {

  		error = -EINVAL;
  		goto out;

  	}
  
  	/* now proceed to make the upcall */

  	cnp = ITOC(target_inode);

  
  	error = venus_pioctl(inode->i_sb, &(cnp->c_fid), cmd, &data);

  out:

  	path_put(&path);

  	return error;

  }