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/* 
   Copyright (C) 1994, 1997 Free Software Foundation

   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, 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, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */

#include <fcntl.h>

#include "priv.h"
#include "io_S.h"

/* Implement io_map as described in <hurd/io.defs>. */
kern_return_t
diskfs_S_io_map (struct protid *cred,
		 memory_object_t *rdobj,
		 mach_msg_type_name_t *rdtype,
		 memory_object_t *wrobj,
		 mach_msg_type_name_t *wrtype)
{
  int flags;
  struct node *node;

  if (!cred)
    return EOPNOTSUPP;

  *wrobj = *rdobj = MACH_PORT_NULL;

  node = cred->po->np;
  flags = cred->po->openstat & (O_READ | O_WRITE);

  mutex_lock (&node->lock);
  switch (flags)
    {
    case O_READ | O_WRITE:
      *wrobj = *rdobj = diskfs_get_filemap (node, VM_PROT_READ |VM_PROT_WRITE);
      if (*wrobj == MACH_PORT_NULL)
	goto error;
      mach_port_mod_refs (mach_task_self (), *rdobj, MACH_PORT_RIGHT_SEND, 1);
      break;
    case O_READ:
      *rdobj = diskfs_get_filemap (node, VM_PROT_READ);
      if (*rdobj == MACH_PORT_NULL)
	goto error;
      break;
    case O_WRITE:
      *wrobj = diskfs_get_filemap (node, VM_PROT_WRITE);
      if (*wrobj == MACH_PORT_NULL)
	goto error;
      break;
    }
  mutex_unlock (&node->lock);

  *rdtype = MACH_MSG_TYPE_MOVE_SEND;
  *wrtype = MACH_MSG_TYPE_MOVE_SEND;

  return 0;
  
error:
  mutex_unlock (&node->lock);
  return errno;
}